bluuebunny/crossref_metadata_2025_split huggingface dataset:
ANT2 expression under hypoxic conditions produces opposite cell‐cycle behavior in 143B and HepG2 cancer cells
Authors: Chevrollier Arnaud , Loiseau Dominique , Gautier Fabien , Malthièry Yves , Stepien Georges 
Published: October 2004

AbstractUnder hypoxic conditions, mitochondrial ATP production ceases, leaving cells entirely dependent on their glycolytic metabolism. The cytoplasmic and intramitochondrial ATP/ADP ratios, partly controlled by the adenine nucleotide translocator (ANT), are drastically modified. In dividing and growing cells that have a predominantly glycolytic metabolism, the ANT isoform 2, which has kinetic properties allowing ATP import into mitochondria, is over‐expressed in comparison to control cells. We studied the cellular metabolic and proliferative response to hypoxia in two transformed human cell lines with different metabolic backgrounds: HepG2 and 143B, and in their ρ° derivatives, i.e., cells with no mitochondrial DNA. Transformed 143B and ρ° cells continued their proliferation whereas HepG2 cells, with a more differentiated phenotype, arrested their cell‐cycle at the G1/S checkpoint. Hypoxia induced an increase in glycolytic activity, correlated to an induction of VEGF and hexokinase II (HK II) expression. Thus, according to their tumorigenicity, transformed cells may adopt one of two distinct behaviors to support hypoxic stress, i.e., proliferation or quiescence. Our study links the constitutive glycolytic activity and ANT2 expression levels of transformed cells with the loss of cell‐cycle control after oxygen deprivation. ATP import by ANT2 allows cells to maintain their mitochondrial integrity while acquiring insensitivity to any alterations in the proteins involved in oxidative phosphorylation. This loss of cell dependence on oxidative metabolism is an important factor in the development of tumors. © 2004 Wiley‐Liss, Inc.
Motor training as treatment in focal hand dystonia
Authors: Zeuner Kirsten E. , Shill Holly A. , Sohn Young H. , Molloy Fiona M. , Thornton Bonnie C. , Dambrosia James M. , Hallett Mark 
Published: October 2004

AbstractFocal hand dystonia may arise as a result of aberrant plasticity from excessive repetitive use. Improvement might be possible with appropriate motor training. Focusing on trying to decrease abnormal overflow of movement to fingers not involved in a task, we developed a motor training program for individualized finger movements. Ten patients with writer's cramp participated in the motor training program. Evaluation was done with the Fahn dystonia scale, kinematic analysis of handwriting, transcranial magnetic stimulation (TMS), and electroencephalography (EEG). Clinical improvement of dystonia was significant using the Fahn dystonia scale, and 6 patients reported an improvement in writing. The handwriting analysis showed a trend for improvement after training in simple exercises. There were no changes in cortical excitability measured by TMS and EEG. Whereas this method of motor training for 4 weeks led to mild subjective improvement and some improvement in handwriting, it is not sufficient to reverse motor cortex abnormalities measured by TMS and EEG. Published 2004 John Wiley & Sons
Acute neuropathy mimicking porphyria induced by aminolevulinic acid during photodynamic therapy
Authors: Sylantiev Constantin , Schoenfeld Nili , Mamet Rivka , Groozman Galina B. , Drory Vivian E. 
Published: October 2004

AbstractAn 82‐year‐old man developed severe, acute, predominantly motor polyneuropathy, signs of autonomic involvement, and skin changes following aminolevulinic acid (ALA) administration. The compound was used as a prodrug for photodynamic therapy of Barrett's esophagitis. Changes were observed in various parameters of the heme pathway. The case reported represents a rare response to ALA treatment, resembling an acute attack of hepatic porphyria with neurological features. Muscle Nerve, 2005
Effects of alcohol on skeletal and cardiac muscle
Authors: Urbano‐Márquez Alvaro , Fernández‐Solà Joaquim 
Published: October 2004

AbstractThe acute and chronic toxic effects of alcohol on skeletal and cardiac muscle are clinically important. Muscle weakness and atrophy are the main manifestations of skeletal myopathy, and arrhythmias and progressive left‐ventricular dysfunction are those of cardiomyopathy. Most patients remain asymptomatic from these effects for a long time. Myocyte atrophy and death are the main pathological findings. A clear dose‐related effect has been established with ethanol consumption, with gender and some specific gene polymorphisms being factors of increased susceptibility to alcohol‐induced muscle damage. Pathogenic mechanisms are pleiotropic, the most relevant being disturbances in carbohydrate, protein, and energy cell turnover, signal transduction, and induction of apoptosis and gene dysregulation. Ethanol abstinence is the only effective treatment, although controlled drinking is useful in patients who do not achieve abstinence. Persistent high‐dose consumption results in deterioration of muscle and heart function, with a high mortality due to arrhythmias and progression of heart failure. Muscle Nerve, 2004
First report of overactive detrusor in association with hypospadias detected by urodynamic screening
Authors: Ozkurkcugil Cuneyd , Guvenc B. Haluk , Dillioglugil Ozdal 
Published: October 2004

AbstractAimsThe purpose of this study was to determine urodynamic features in hypospadic patients.MethodsThirty‐seven patients with hypospadias (distal: 31, proximal: 6) underwent preoperative urodynamic study according to International Continence Society (ICS) recommendations. Statistical analysis were done for comparison between urethral obstruction and non‐obstruction in patients with detrusor overactivity (DO) plus the relationship of DO with localization of hipospadias.ResultsNearly 45.9% of the patients showed overactive detrusor. Urethral obstruction was found in 60.8% of the patients. The rate of DO was higher in proximal hipospadias, and urethral obstruction than distal type, and non‐obstructed patients (P > 0.005). The means overall cystometric capacity, maximum voiding detrusor pressure and maximal urinary flow measured were 132.6 ± 111.14 ml (range 21–610), 72 ± 53 cmH2O (range 12–181), and 7.9 ± 7.1 ml/sec (range 2–30 ml/sec), respectively.ConclusionsTo the best of our knowledge, this is the first study ever to show that overactive detrusor is an accompanying entity in the hypospadic patients. © 2004 Wiley‐Liss, Inc.
A network flow approach to cost allocation for rooted trees
Authors: Iwata Satoru , Zuiki Nozomu 
Published: October 2004

AbstractIn the game theory approach to cost allocation, the main computational issue is an algorithm for finding solutions such as the Shapley value and the nucleolus. In this article, we consider the problem of allocating the maintenance cost of a tree network that connects the supply source at the root to the users at the leaves. We show that the core of the game can be expressed in terms of network flows. Based on this observation, we present O(n log n) algorithms for computing the nucleolus and the egalitarian allocation. © 2004 Wiley Periodicals, Inc. NETWORKS, Vol. 44(4), 297–301 2004
Population density regulates Drosophila synaptic morphology in a Fasciclin‐II‐dependent manner
Authors: Stewart Bryan A. , McLean Jesse R. 
Published: October 2004

AbstractGenetic analysis of the Drosophila larval neuromuscular junction has identified some of the key molecules that regulate synaptic plasticity. Among these molecules, the expression level of Fasciclin II (FasII), a homophilic cell adhesion molecule, is critically important for determining the final form of the neuromuscular junction. Genetic reduction of FasII expression by 50% yields more elaborate nerve terminals, while a greater reduction in expression, to 10% of wild‐type, yields a substantial reduction in the nerve terminal morphology. Importantly, regulation of FasII expression seems to be the final output for several genetic manipulations that transform NMJ morphology. In an effort to understand the importance of this regulatory pathway in the normal animal, we have undertaken studies to identify environmental cues that might be important for initiating FasII‐dependent changes in synaptic plasticity. Here we report on the relationship between larval population density and synaptic morphology, synaptic strength, and FasII levels. We raised Drosophila larvae under conditions of increasing population density and found an inverse exponential relationship between population density and the number of synaptic boutons, the number of branches, and the length of branches. We also observed population‐dependent alteration in FasII levels, with lower densities having less FasII at the synapse. The correlation between density and morphological change was abrogated in larvae constitutively expressing FasII, and in wild‐type larvae grown on soft culture medium. Together these data show that environmental cues can induce regulation of FasII. Interestingly, however, the quantal content of synaptic transmission was not different among the different population densities, suggesting that other factors contribute to maintaining synaptic strength at a defined level. © 2004 Wiley Periodicals, Inc. J Neurobiol, 2004
A FETI‐based multi‐time‐step coupling method for Newmark schemes in structural dynamics
Authors: Prakash A. , Hjelmstad K. D. 
Published: October 2004

AbstractWe present an efficient and accurate multi‐time‐step coupling method using FETI domain decomposition for structural dynamics. Using this method one can divide a large structural mesh into a number of smaller subdomains, solve the individual subdomains separately and couple the solutions together to obtain the solution to the original problem. The various subdomains can be integrated in time using different time steps and/or different Newmark schemes. This approach will be most effective for very large‐scale simulations on complex geometries.Our coupling method builds upon a method previously proposed by Gravouil and Combescure (GC method). We show that for the simplest case when the same time step is used in all subdomains of the mesh our method reduces to the GC method and is unconditionally stable and energy preserving. In addition, we show that our method possesses these desirable properties for general multi‐time‐step cases too unlike the GC method which is dissipative. Greater computational efficiency is also achieved through our method by limiting the computation of interface forces to the largest time step as opposed to the smallest time step in the GC method. Copyright © 2004 John Wiley & Sons, Ltd.
Higher‐order extensions of a discontinuous Galerkin method for mid‐frequency Helmholtz problems
Authors: Farhat Charbel , Tezaur Radek , Weidemann‐Goiran Paul 
Published: October 2004

AbstractRecently, a discontinuous Galerkin method with plane wave basis functions and Lagrange multiplier degrees of freedom was proposed for the efficient solution of Helmholtz problems in the mid‐frequency regime. In this paper, this method is extended to higher‐order elements. Performance results obtained for various two‐dimensional problems highlight the advantages of these elements over classical higher‐order Galerkin elements such as Q2 and Q4 for the discretization of interior and exterior Helmholtz problems. Copyright © 2004 John Wiley & Sons, Ltd.
A stabilized one‐point integrated quadrilateral Reissner–Mindlin plate element
Authors: Gruttmann F. , Wagner W. 
Published: October 2004

AbstractA new quadrilateral Reissner–Mindlin plate element with 12 element degrees of freedom is presented. For linear isotropic elasticity a Hellinger–Reissner functional with independent displacements, rotations and stress resultants is used. Within the mixed formulation the stress resultants are interpolated using five parameters for the bending moments and four parameters for the shear forces. The hybrid element stiffness matrix resulting from the stationary condition can be integrated analytically. This leads to a part obtained by one‐point integration and a stabilization matrix. The element possesses a correct rank, does not show shear locking and is applicable for the evaluation of displacements and stress resultants within the whole range of thin and thick plates. The bending patch test is fulfilled and the computed numerical examples show that the convergence behaviour is better than comparable quadrilateral assumed strain elements. Copyright © 2004 John Wiley & Sons, Ltd.
Optimal design and optimal control of structures undergoing finite rotations and elastic deformations
Authors: Ibrahimbegovic A. , Knopf‐Lenoir C. , Kučerová A. , Villon P. 
Published: October 2004

AbstractIn this work, we deal with the optimal design and optimal control of structures undergoing large rotations and large elastic deformations. In other words, we show how to find the corresponding initial configuration through optimal design or the corresponding set of multiple load parameters through optimal control, in order to recover a desired deformed configuration or some desirable features of the deformed configuration as specified more precisely by the objective or cost function. The model problem chosen to illustrate the proposed optimal design and optimal control methodologies is the one of geometrically exact beam. First, we present a non‐standard formulation of the optimal design and optimal control problems, relying on the method of Lagrange multipliers in order to make the mechanics state variables independent from either design or control variables and thus provide the most general basis for developing the best possible solution procedure. Two different solution procedures are then explored, one based on the diffuse approximation of response function and gradient method and the other one based on genetic algorithm. A number of numerical examples are given in order to illustrate both the advantages and potential drawbacks of each of the presented procedures. Copyright © 2004 John Wiley & Sons, Ltd.
Sounding of finite solid bodies by way of topological derivative
Authors: Bonnet Marc , Guzina Bojan B. 
Published: October 2004

AbstractThis paper is concerned with an application of the concept of topological derivative to elastic‐wave imaging of finite solid bodies containing cavities. Building on the approach originally proposed in the (elastostatic) theory of shape optimization, the topological derivative, which quantifies the sensitivity of a featured cost functional due to the creation of an infinitesimal hole in the cavity‐free (reference) body, is used as a void indicator through an assembly of sampling points where it attains negative values. The computation of topological derivative is shown to involve an elastodynamic solution to a set of supplementary boundary‐value problems for the reference body, which are here formulated as boundary integral equations. For a comprehensive treatment of the subject, formulas for topological sensitivity are obtained using three alternative methodologies, namely (i) direct differentiation approach, (ii) adjoint field method, and (iii) limiting form of the shape sensitivity analysis. The competing techniques are further shown to lead to distinct computational procedures. Methodologies (i) and (ii) are implemented within a BEM‐based platform and validated against an analytical solution. A set of numerical results is included to illustrate the utility of topological derivative for 3D elastic‐wave sounding of solid bodies; an approach that may perform best when used as a pre‐conditioning tool for more accurate, gradient‐based imaging algorithms. Despite the fact that the formulation and results presented in this investigation are established on the basis of a boundary integral solution, the proposed methodology is readily applicable to other computational platforms such as the finite element and finite difference techniques. Copyright © 2004 John Wiley & Sons, Ltd.
Tumor response and toxicity with multiple infusions of high dose 131I‐MIBG for refractory neuroblastoma
Authors: Howard James P. , Maris John M. , Kersun Leslie S. , Huberty John P. , Cheng Su‐Chun , Hawkins Randall A. , Matthay Katherine K. 
Published: October 2004

AbstractBackground131I Metaiodobenzylguanidine (131I‐MIBG) is an effective targeted radiotherapeutic for neuroblastoma with response rates greater than 30% in refractory disease. Toxicity is mainly limited to myelosuppression. The aim of this study was to determine the response rate and hematologic toxicity of multiple infusions of 131I‐MIBG.ProcedurePatients received two to four infusions of 131I‐MIBG at activity levels of 3–19 mCi/kg per infusion. Criteria for subsequent infusions were neutrophil recovery without stem cell support and lack of disease progression after the first infusion.ResultsSixty‐two infusions were administered to 28 patients, with 24 patients receiving two infusions, two patients receiving three infusions, and two patients receiving four infusions. All patients were heavily pre‐treated, including 16 with prior myeloablative therapy. Eleven patients (39%) had overall disease response to multiple therapies, including eight patients with measurable responses to each of two or three infusions, and three with a partial response (PR) after the first infusion and stable disease after the second. The main toxicity was myelosuppression, with 78% and 82% of patients requiring platelet transfusion support after the first and second infusion, respectively, while only 50% had grade 4 neutropenia, usually transient. Thirteen patients did not recover platelet transfusion independence after their final MIBG infusion; stem cell support was given in ten patients.ConclusionsMultiple therapies with 131I‐MIBG achieved increasing responses, but hematologic toxicity, especially to platelets, was dose limiting. More effective therapy might be given using consecutive doses in rapid succession with early stem cell support. © 2004 Wiley‐Liss, Inc.
A young girl with hemolytic anemia and elevated hemoglobin F
Authors: Parikh Nehal S. , Hoyer James D. , Cripe Timothy P. 
Published: October 2004

AbstractThe non‐immune, non‐spherocytic anemias result from multiple potential etiologies. We report a 16‐year‐old girl, who was presented with a long‐standing anemia and normal blood screening tests except an elevated hemoglobin F. Her diagnosis of unstable hemoglobinopathy was made only after gene sequencing of the β‐globin chain. © 2004 Wiley‐Liss, Inc.
Benzylpenicillin cleavage with polyelectrolytes
Authors: Arcelli Antonio , Cecchi Romina , Porzi Gianni , Sandri Monica 
Published: October 2004

AbstractKinetic studies of the aminolysis of benzylpenicillin (BP) in poly(ethylenimine) (PEI) showed a complicated rate behaviour owing to the strong substrate–polyelectrolyte interaction. The results were interpreted by the formation of an unreactive and reactive complex which is converted into the poly(ethylenimine)penicilloylamide. In the presence of KCl the PEI behaves as a simple amine and the second‐order rate constants (kN) of the nucleophilic attack on β‐lactam were calculated at various pH values. The Brønsted β value is consistent with a stepwise mechanism in which the rate‐determining step is the T± intermediate decomposition in absence of general acid–base catalysis. The PEI reveals its catalytic ability not only by binding the substrate to the polymer, but also by increasing the reactivity of the reactive complex. A negligible effect on the alkaline hydrolysis of BP was found in the presence of poly(diallyldimethylammonium) chloride (PDDA). A parallel between PEI and human serum albumin (HSA) in the BP aminolysis is proposed. Copyright © 2004 John Wiley & Sons, Ltd.
γ‐Irradiation of ultrahigh‐molecular‐weight polyethylene: Electron paramagnetic resonance and nuclear magnetic resonance spectroscopy and imaging studies of the mechanism of subsurface oxidation
Authors: Alam Todd M. , Celina Mathew , Collier John P. , Currier Barbara H. , Currier John H. , Jackson Simon K. , Kuethe Dean O. , Timmins Graham S. 
Published: October 2004

AbstractThe shelf aging of irradiated ultrahigh‐molecular‐weight polyethylene (UHMWPE) causes subsurface oxidation, which leads to failure in UHMWPE orthopedic components, yet the mechanisms causing subsurface oxidation remain unclear. The shelf aging of γ‐irradiated UHMWPE bars has been studied with electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) imaging and with microtoming and Fourier transform infrared microscopy. The bars initially contained only allyl radicals, and upon air exposure, a surface layer of peroxyl radicals formed through the reaction of allyl radicals with oxygen. Importantly, a band of low radical intensity just beneath the peroxyl layer became apparent. NMR imaging showed a zone of altered proton relaxation in this zone. With increasing time, surface peroxyl radicals persisted in comparison with the interior allyl radicals, although oxygen did not appear to penetrate any more deeply into the bar. The area of maximal oxidation and mechanical disruption, measured after 3 years, was at the interface between the zone of exterior peroxyl radicals and the zone of low radical intensity. We present a mechanism involving the intermediacy of sterically strained reactive dialkyl peroxides at this interface to explain subsurface oxidation. We also demonstrate that EPR and NMR imaging provides information that could potentially be used to identify subsurface oxidized UHMWPE components before failure. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5929–5941, 2004
Preparation and properties of novel benzoxazine and polybenzoxazine with maleimide groups
Authors: Liu Ying‐Ling , Yu Juin‐Meng , Chou Ching‐I 
Published: October 2004

AbstractA benzoxazine compound with a maleimide group, 3‐phenyl‐3,4‐dihydro‐2H‐6‐(N‐maleimido)‐1,3‐benzoxazine (HPM‐Ba), was prepared from N‐(4‐hydroxyphenyl)maleimide, formaldehyde, and aniline. The chemical structure of HBM‐Ba was identified by FT‐IR, 1H‐NMR, and elemental analysis. HPM‐Ba showed a melting point of 52–55 °C and good solubility in common organic solvents. HPM‐Ba showed a two‐stage process of thermal polymerization. The first stage arose from the polymerization of maleimide groups, and the second one was the ring‐opening reaction of benzoxazine groups. Fusible polymaleimides with a Tg of around 100 °C could be obtained by thermally polymerizing HPM‐Ba at 130 °C. Further polymerizing the polymaleimides at 240 °C resulted in a completely cured resin showing a Tg at 204 °C. Good thermal stability and self‐extinguishing behavior was observed with the cured polybenzoxazine resins. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5954–5963, 2004