bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lignin peroxidase‐catalyzed polymerization and detoxification of toxic halogenated phenols
Authors: Ward Gary , Hadar Yitzhak , Dosoretz Carlos G 
Published: November 2003

AbstractHalogenated phenols and bisphenols are recognized as being recalcitrant in conventional biological treatments. The current research evaluated lignin peroxidase‐catalyzed oxidation and polymerization as a potential alternative for their detoxification. Gel permeation–HPLC analysis demonstrated the formation of dimers, trimers and tetramers upon oxidation of the target substrates. Polymerization was accompanied by effective detoxification of the aqueous phase during oxidation of 2,4‐dibromophenol, the extent of which correlated with the extent of oxidation and polymerization. Steady state kinetic measurements at a saturating concentration of H2O2 revealed high Km values (270–1100 µmol dm−3) for the target substrates, reflecting the strong electron‐withdrawing properties of halogen substituents, which increase the oxidation potential of the phenols, resulting in thermodynamically less favorable reactions. However, kcat values were not dissimilar from non‐halogenated phenols and the rapid oxidation and polymerization suggests that low retention times could be expected in a continuous process for their treatment, in contrast to conventional biological methods. The operational stability of lignin peroxidase was significantly improved by inclusion of redox mediators, which resulted in enhanced oxidation and more rapid reaction rates. However, due to their inherent toxicity, the use of redox mediators impeded toxicity assays. The findings highlight the potential of lignin peroxidase as a possible alternative for the high‐rate treatment of industrial wastewater when conventional methods are ineffective. Copyright © 2003 Society of Chemical Industry
Convenient and efficient deuteration of functionalized aromatics with deuterium oxide: catalysis by cycloocta‐1,5‐dienyliridium(I) 1,3‐dionates
Authors: McAuley B. , Hickey M. J. , Kingston L. P. , Jones J. R. , Lockley W. J. S. , Mather A. N. , Spink E. , Thompson S. P. , Wilkinson D. J. 
Published: November 2003

AbstractAromatic compounds bearing an ortho‐directing substituent may be deuterated by exchange with deuterium oxide in the presence of a range of cycloocta‐1,5‐dienyliridium(I)1,3‐dionate catalysts. The exchange takes place in several dipolar aprotic solvents and is directly applicable to the deuteration of polar compounds. Isotope incorporation is efficient and regiospecific. The method is applicable to a wide range of ortho‐directing groups some of which are only weak directors for alternative ortho‐labelling approaches. In addition, the application of microwaves enables labelling within minutes even with sub‐stituents which are poor directors. Copyright © 2003 John Wiley & Sons, Ltd.
The evolution of the apparent diffusion coefficient in the pediatric brain at low and high diffusion weightings
Authors: Jones Richard A. , Palasis Susan , Grattan‐Smith J. Damien 
Published: November 2003

AbstractPurposeTo evaluate the evolution of the apparent diffusion coefficient (ADC) with age for different degrees of diffusion weighting using a clinically feasible approach.Materials and MethodsData was acquired using separate scans with b values in the range typically used for clinical studies (100–900 seconds/mm2) and higher b values (1800–3000 seconds/mm2). The ADC was calculated for each of the data sets by fitting the data to a monoexponential function.ResultsThe results from 50 children aged three years and less showed some deviations from literature values derived using a full biexponential fit, with these differences reflecting the approximations inherent in this approach. The values obtained with this technique appear to be reproducible but the resulting “institutional values” are comparable to those from other centers only if identical measurement criteria are used.ConclusionA significant decline in both components of the ADC during the first few months of life was observed; in addition, the attenuated slow ADC values seen in adult white matter were only present at birth in early myelinating regions. The subsequent development of the slow ADC in white matter suggests that it is associated with myelination or processes associated with axonal development. J. Magn. Reson. Imaging 2003;18:665–674. © 2003 Wiley‐Liss, Inc.
Using an adaptive semiautomated self‐evaluated registration technique to analyze MRI data for myocardial perfusion assessment
Authors: Delzescaux Thierry , Frouin Frédérique , De Cesare Alain , Philipp‐Foliguet Sylvie , Todd‐Pokropek Andrew , Herment Alain , Janier Marc 
Published: November 2003

AbstractPurposeTo validate the adaptive semiautomated self‐evaluated registration technique (ASSERT) followed by factor analysis of medical image sequence (FAMIS) for analyzing myocardial perfusion using magnetic resonance imaging (MRI) images.Materials and MethodsEleven patients having a significant stenosis of at least one coronary artery detected by coronarography were examined by thallium tomoscintigraphy and perfusion MRI (first‐pass of Gd‐DTPA‐BMA) at rest and under pharmacologic stress. The MRI images were analyzed by ASSERT to correct for rigid motion in the acquisition plane and to reject those images that were severely deformed or acquired outside the slice plane. The images thus obtained were analyzed by FAMIS. The resulting factor images representing myocardial perfusion were read to identify the ischemic territories corresponding to left anterior descending coronary arteries and right coronary arteries.ResultsASSERT allowed automatic correction for motion and the exclusion of images that could not be registered. The ischemic territories, identified from the factor images of the myocardium, agreed with those identified by coronarography and tomoscintigraphy for 20 of the 22 territories.ConclusionThe results demonstrate the feasibility of analyzing myocardial perfusion using MRI acquisition and treating the resulting images by ASSERT and FAMIS. Extending this method to multislice examinations will enable evaluation of the perfusion of the whole myocardium. J. Magn. Reson. Imaging 2003;18:681–690. © 2003 Wiley‐Liss, Inc.
N‐(2‐Hydroxypropyl)methacrylamide (HPMA) Copolymer‐Linked Nitroxides: Potential Magnetic Resonance Contrast Agents
Authors: Huang Yuan , Nan Anjan , Rosen Gerald M. , Winalski Carl S. , Schneider Erika , Tsai Pei , Ghandehari Hamidreza 
Published: November 2003

AbstractN‐(2‐Hydroxypropyl)methacrylamide (HPMA) copolymer‐linked nitroxides were synthesized as macromolecular contrast agents for MR imaging. Molar relaxivities of HPMA copolymer‐linked nitroxides increased linearly in proportion to the number of nitroxides attached per gram of copolymer. HPMA copolymer‐linked nitroxides with 15, 20 and 30 mol‐% nitroxide exhibited higher relaxivities than gadolinium diethylenetriaminepentaacetic acid (Gd‐DTPA). These results demonstrate the potential of HPMA copolymer‐linked nitroxides as MR contrast agents for solid tumors.Structure of HPMA copolymer‐linked nitroxides.magnified imageStructure of HPMA copolymer‐linked nitroxides.
Thin Films by Multilayer Build‐Up of Electron Transport Materials
Authors: Mruk Ralf , Prehl Sabine , Zentel Rudolf 
Published: November 2003

AbstractWe present the synthesis and the electrochemical characterization of polymeric electron transport materials, synthesized by polycondensation of substituted triazines and α,ω‐dihaloalkanes. They can be reversibly reduced with the least negative potential at −0.39 V, which is below the reduction potential of oxygen. In addition, the formation of polyelectrolyte multilayers is possible by the electrostatic self‐assembly method. This multilayer formation takes place in a very defined way up to thirty double layers.An example of one of the polymeric triazine electron transport materials synthesized and a schematic diagram of a self‐assembled multilayer film.magnified imageAn example of one of the polymeric triazine electron transport materials synthesized and a schematic diagram of a self‐assembled multilayer film.
Liquid Adsorption Chromatography Separation of Star Poly(methyl methacrylate)s
Authors: Lazzari Massimo , Jančo Miroslav , Kitayama Tatsuki , Hatada Koichi 
Published: November 2003

AbstractLiquid adsorption chromatography, in combination with full adsorption–desorption and precipitation–redissolution techniques, is a powerful procedure for the fractionation of mixtures in the synthesis of star polymers. An easy separation of 4‐ and 6‐arm star poly(methyl methacrylate)s from their single arm precursors could be carried out by both procedures, with differences of separation efficiency also depending on the molecular weight of the precursor and the number of arms.Size exclusion chromatograms of retained and eluted fractions obtained by liquid adsorption chromatography/full adsorption–desorption separation with a tetrahydrofuran/cyclohexane eluent system (53:47 wt.‐%) for a crude reaction mixture (dotted line) containing a 4‐arm star PMMA polymer and a single‐arm precursor (solid lines a and b, respectively).magnified imageSize exclusion chromatograms of retained and eluted fractions obtained by liquid adsorption chromatography/full adsorption–desorption separation with a tetrahydrofuran/cyclohexane eluent system (53:47 wt.‐%) for a crude reaction mixture (dotted line) containing a 4‐arm star PMMA polymer and a single‐arm precursor (solid lines a and b, respectively).
Suppression of the transformed phenotype and induction of differentiation‐like characteristics in cultured ovarian tumor cells by chronic treatment with progesterone
Authors: Blumenthal Martina , Kardosh Adel , Dubeau Louis , Borok Zea , Schönthal Axel H. 
Published: November 2003

AbstractEpidemiological evidence suggests that elevated levels of the pregnancy hormone progesterone might play a role in the reduced risk of women to develop ovarian cancer. In vitro studies have supported this hypothesis by demonstrating negative effects of this hormone on the growth and proliferation of cultured ovarian carcinoma cells. However, little is known about the underlying molecular processes and how progesterone might decrease the risk for ovarian tumors. Therefore, we investigated the effects of chronic hormone treatment on the cell‐cycle and transformed phenotype of ovarian carcinoma cell lines in vitro. We found that long‐term treatment of these cells with progesterone caused a concomitant reduction of cyclin‐dependent kinase (CDK) activity. In parallel, these cells lost their transformed phenotype as indicated by the acquisition of contact inhibition and the loss of anchorage‐independence, as well as the reduced expression of tumor markers such as heat shock protein (HSP) 72 and carcinoma antigen (CA) 125. In addition, progesterone‐treated cells exhibited characteristics that resembled a more differentiated phenotype. Taken together, our data indicated that progesterone was able to suppress the transformed phenotype of ovarian tumor cells. This observation could serve to explain progesterone's alleged protective effect in ovarian carcinogenesis. © 2003 Wiley‐Liss, Inc.
Pure akinesia: An unusual phenotype of Hallervorden‐Spatz syndrome
Authors: Molinuevo José L. , Martí María J. , Blesa Rafael , Tolosa Eduardo 
Published: November 2003

AbstractTwo siblings were seen in our outpatient movement disorders clinic with an indolent clinical picture of a pure akinesia syndrome. Magnetic resonance showed the typical “eye of the tiger” sign, and genetic screening disclosed that both siblings were compound heterozygotes with two missense mutations in the PANK2 gene 734A→G and 1172T→C. This case report highlights the phenotypic diversity of Hallervorden Spatz syndrome and the need for further investigation of adult‐onset pure akinesia syndromes. © 2003 Movement Disorder Society
Treatment of Sydenham chorea with corticosteroids
Authors: Cardoso Francisco , Maia Débora , Cunningham Mauro César Q.S. , Valença Guilherme 
Published: November 2003

AbstractDespite treatment with valproic acid and neuroleptics, a significant proportion of patients with Sydenham chorea (SC) remain with chorea. We evaluated the effect of intravenous methyl‐prednisolone followed by oral prednisone in patients with SC refractory to conventional treatment. Patients were enrolled in the study if they failed to improve with conventional treatment, despite the development of side effects. Chorea was rated on a 0 to 4 score. Five patients, 3 of them women, were included in the study. The median pretreatment rating score of the chorea was 3 (range, 3–4) and dropped to 1 (range, 0–2) after a median follow‐up of 7 months (range, 3–7 months). Two patients developed Cushing syndrome. Our data suggest that intravenous methyl‐prednisolone followed by oral prednisone is an effective and well‐tolerated treatment of refractory SC. © 2003 Movement Disorder Society
Diagnostic potential of acoustic startle reflex, acoustic blink reflex, and electro‐oculography in progressive supranuclear palsy: A prospective study
Authors: Gironell Alexandre , Kulisevsky Jaime , Roig Carles , Pascual‐Sedano Berta , Rodríguez‐Fornells Antoni , Otermin Pilar 
Published: November 2003

AbstractWe carried out a prospective study to analyze the diagnostic potential of acoustic startle reflex (ASR), acoustic blink reflex (ABR) and electro‐oculography (EOG) in early stages of atypical parkinsonian syndrome. The study was carried out in a consecutive series of 41 patients clinically diagnosed as atypical parkinsonism (mean time from first symptoms of 38 months and follow‐up of 26 months). The three procedures were carried out immediately after the first clinical evaluation. ASR and ABR were elicited by auditory stimuli while the patient was attending to a simple reaction time task. Outcome measures were: ASR (absence/presence, latency), ABR (absence/presence, latency) and EOG (suggestive/not suggestive of progressive supranuclear palsy [PSP]). Final clinical diagnosis was carried out by two neurologists blind to the neurophysiological results. A study of diagnostic sensitivity and odds ratio (OR) calculation for the PSP diagnosis was carried out. Neurophysiological examination showed the following sensitivity/specificity (%) for the diagnosis of PSP: ASR: 100/89; ABR 85/89; EOG 100/72. OR values were: ASR: 0.011; ABR: 0.037; EOG: 0.038. The three tests taken simultaneously showed a sensitivity of 100% and a specificity of 95%. The three neurophysiological tests investigated provided sensitive and specific measures with predictor value in early stages of atypical parkinsonian syndrome. © 2003 Movement Disorder Society
A computer model of rigidity and related motor dysfunction in Parkinson's disease
Authors: Le Cavorzin Philippe , Carrault Guy , Chagneau Francis , Rochcongar Pierre , Allain Hervé 
Published: November 2003

AbstractThis work explores the involvement of spinal circuits in the generation of parkinsonian rigidity and related motor dysfunction. A computer model of spinal proprioceptive input processing, derived from previous work on spasticity modeling, was adapted to the simulation of parkinsonian rigidity. Model parameters were varied to generate simulations reproducing experimental data obtained using the pendulum test of the leg in 10 parkinsonian patients and 3 healthy subjects. Convenient reproductions of experimental traces in rigidity were obtained by the combination of a low reflex gain and a decrease in reflex threshold. These findings are consistent with studies reporting an increase of spinal interneuron excitability and proprioception deficits in Parkinson's disease (PD). Moreover, as the threshold parameter was much lowered, our model generated typical features of parkinsonian resting tremor, endorsing the hypothesis of a participation of a spinal oscillator in this disorder. Finally, tuning the reflex gain during simulations of rigidity resulted in the generation of active movement, opening some hypotheses on pathophysiology of motor dysfunction in PD, and notably, of akinesia. More generally, this work accredits the hypothesis of the involvement of an aperiodic, altered supra‐spinal motor drive in PD, resulting in spinal dysfunction, through specific descending motor pathways. This may lead to a search for new (spinal) pharmacological targets in PD. It emphasizes further the value of computer modeling in understanding motor control in health and disease. © 2003 Movement Disorder Society
Parkin variants in North American Parkinson's disease: Cases and controls
Authors: Lincoln Sarah J. , Maraganore Demetrius M. , Lesnick Timothy G. , Bounds Rebecca , de Andrade Mariza , Bower James H. , Hardy John A. , Farrer Matthew J. 
Published: November 2003

AbstractWe report on an evaluation of coding variants within the parkin gene to assess their frequency in a North American clinical series of 313 Parkinson's disease (PD) cases and 192 unrelated controls. We hypothesized that the carrier frequency of parkin coding mutations, exon deletions, or duplications may be greater in PD cases. However, point mutations and exonic deletions/duplications, reported previously as pathogenic in homozygous or compound heterozygous individuals, occurred in both cases and controls with similar frequencies (3.8% in cases, 3.1% in controls). Furthermore, only stratified subanalyses detected any genetic association between the V380L common coding polymorphism and PD. We discuss the implication of parkin mutations for Parkinson's disease from this population perspective. © 2003 Movement Disorder Society
Severe cervical dystonia in pathologically proven Parkinson's disease and dementia (PDD)
Authors: Cohen Oren , Fahn Stanley , Frucht Steven J. 
Published: November 2003

AbstractWe describe and present a videotape of a patient with parkinsonism and dementia who developed severe cervical dystonia, despite treatment with levodopa and botulinum toxin. The clinical diagnosis of Parkinson's disease and dementia (PDD) was confirmed at autopsy. © 2003 Movement Disorder Society
Dependence of the pure quadrupole resonance frequency on temperature for KBrO3
Authors: Stahl Edward A. , Herzog Siegfried 
Published: November 2003

AbstractThe pure quadrupole resonance frequency of KBrO3 in the temperature range 4.17–300.16 K was determined experimentally and compared with the model developed by Stahl which contains three adjustable constants. Excellent agreement between the experimental data and the model was obtained when considering only the temperature range 4.17–52 K. As a result of the comparison, the following values are suggested for KBrO3: the resonance frequency at 0 K is 179.50373 MHz, the Debye temperature, Θd, is 108 K, and the rotational energy, Iωl2, of each of the first two modes of oscillation of the BrO3 group is 1.707 × 10−18 kg m2. Here I is the moment of inertia and ωl is the lattice vibration frequency. Comparison of model and experimental data over the entire temperature range from 4.17 to 300.16 K shows that the suggested theory reflects very well the general trend of the experimental data but lacks in some detail. Copyright © 2003 John Wiley & Sons, Ltd.
Total assignments of 1H and 13C NMR spectra of biflorin and bis‐biflorin from Capraria biflora
Authors: Fonseca Aluisio M. , Pessoa Otília D. L. , Silveira Edilberto R. , Monte Francisco J. Q. , Braz‐Filho Raimundo , Lemos Telma L. G. 
Published: November 2003

AbstractBis‐biflorin, a new o‐naphthoquinone dimer, and biflorin, 6,9‐dimethyl‐3‐(4‐methyl‐3‐pentenyl)naphtho[1,8‐bc]‐pyran‐7,8‐dione, were isolated from roots of Capraria biflora, a medicinal plant from northeast Brazil. Structural elucidation was made on the basis of spectral data, mainly by high‐field NMR and high‐resolution mass spectrometry. Copyright © 2003 John Wiley & Sons, Ltd.
Conformational analysis. Part 40: a theoretical and NMR investigation of the conformations of cis‐ and trans‐cyclopentane‐1,3‐diol
Authors: Abraham Raymond J. , Koniotou Rodothea 
Published: November 2003

AbstractThe conformations of cis‐ (1) and trans‐cyclopentane‐1,3‐diol (2) have been studied by ab initio (Gaussian 98) and molecular mechanics (PCMODEL) calculations and by NMR spectroscopy. The calculations gave two low‐energy conformations for (1), 1A and 1B, both with axial hydroxyl groups. Two conformations with equatorial hydroxyl groups (1C and 1D) were found but with much higher energy (ca 4.0 kcal mol−1). Five low‐energy conformers were found for 2. Four were envelope conformations and one a half‐chair. The complete analysis of the 400 MHz 1H NMR spectra of 1 in a variety of solvents and 2 in chloroform was performed by extensive decoupling experiments, iterative computer analysis and spectral simulation. This gave all the H,H couplings in the molecule, including in 1 a long‐range 4J(H,H) coupling between H‐2cis and H‐4,5cis. The 3J(H,H) couplings were used to determine the conformer populations in these molecules. This was initially achieved using the Haasnoot, de Leeuw and Altona equation. to obtain the conformer couplings. It was found that this equation was not accurate for the C·CH2·CH2·C fragment in these molecules and the following equation was derived for this fragment from five‐ and six‐ membered cyclic compounds in fixed conformations:

The conformer populations were obtained by calculating the conformer couplings which were then compared with the observed couplings. Compound 1 in benzene solution is an approximately equal mixture of conformers 1A and 1B with small (<4%) amounts of 1C and 1D. In the polar solvents acetone and acetonitrile the populations of 1A and 1B are again equal, with 20% of 1C and <2% of 1D. In 2 the major conformers are 2B and 2D with small amounts of 2C, 2E and 2A. These novel findings are considered with previous data on cyclopentanol and cis‐ and trans‐cyclopentane‐1,2‐diol and it is shown that the axial hydroxyl substituent at the fold of the envelope appears to be a major factor in determining the conformational energies of these compounds. Copyright © 2003 John Wiley & Sons, Ltd.
Ocular myasthenia gravis associated with euthyroid ophthalmopathy
Authors: Kusuhara Tomohiko , Nakajima Masashi , Imamura Akiko 
Published: November 2003

AbstractWe report a 71‐year‐old woman with concomitant ocular myasthenia gravis and euthyroid Graves' ophthalmopathy. Unilateral ophthalmoplegia, including ptosis, initially was responsive to edrophonium and corticosteroids, except for diplopia on upward gaze, but refractory swelling of the inferior rectus muscle and proptosis followed. Autoantibodies to acetylcholine and thyrotropin receptors were detected. Her ophthalmopathy abated after orbital irradiation in combination with systemic steroids. There may be an immunological basis for the association of ocular myasthenia gravis with euthyroid Graves' ophthalmopathy. Muscle Nerve 28: 764–766, 2003
Acute neuropathies after peripheral blood stem cell and bone marrow transplantation
Authors: Rabinstein Alejandro A. , Dispenzieri Angela , Micallef Ivana N. , Inwards David J. , Litzow Mark R. , Wijdicks Eelco F. M. 
Published: November 2003

AbstractNeuromuscular complications are not uncommon after bone marrow and stem cell transplantation, especially in patients with allogeneic transplantations and graft‐versus‐host disease. The pathogenesis of these complications remains unclear, but the changes in immune modulation that occur after transplantation are likely to play a key role. We describe 4 patients who developed brachial plexopathy (3 cases) or multiple lumbosacral radiculopathies (1 case) between 5 days and 4 months after autologous peripheral blood stem cell (3 cases) or allogeneic bone marrow transplantation without evidence of graft‐versus‐host disease (1 case). Infectious, tumor‐related, toxic, and metabolic causes were excluded in all cases. Recovery was limited in two cases and nearly complete in the other two patients. Brachial plexopathies and polyradiculopathies are potential complications of peripheral blood stem cell and bone marrow transplantation. It is possible that these disorders may be the result of autoimmune phenomena directed against specific nerve antigens. Muscle Nerve 28: 733–736, 2003