Frequency Decreases (frequency + decrease)

Distribution by Scientific Domains


Selected Abstracts


Efficacy and Safety of Levetiracetam in Children with Partial Seizures: An Open-label Trial

EPILEPSIA, Issue 5 2002
Tracy A. Glauser
Summary: ,Purpose: To assess the efficacy and safety of levetiracetam (LEV) as adjunctive therapy in children with treatment-resistant partial-onset seizures. Methods: Children (aged 6,12 years) with treatment-resistant partial-onset seizures receiving one standard antiepileptic drug (AED) were eligible. After a 4-week baseline period, children received LEV in a 6-week titration phase (target dose, 40 mg/kg/day) followed by an 8-week evaluation phase. Seizure frequency during the evaluation period with individualized LEV doses (20,40 mg/kg/day) were compared with the 4-week baseline seizure frequency. Plasma concentrations of LEV and other AEDs were determined to evaluate potential drug interactions. Results: Twenty-four subjects enrolled and received LEV; 23 entered the evaluation phase, and 22 completed the evaluation phase. Compared with their baseline seizure frequency, 12 (52%) of 23 subjects entering the evaluation phase had their seizure frequency decrease by >50%. Two subjects remained seizure free during the entire evaluation period. LEV did not significantly affect plasma concentrations of any concomitant AED during this study, and no alteration of mean clinical laboratory values was observed. The most commonly reported adverse events were headache, infection, anorexia, and somnolence. Conclusions: This open-label study of adjunctive LEV therapy (at 20,40 mg/kg/day) suggests that LEV is effective, safe, and well tolerated in children ages 6,12 years with treatment-resistant partial-onset seizures. A randomized, placebo-controlled, double-blind trial of LEV adjunctive therapy in children with treatment-resistant partial-onset seizures is needed and ongoing to confirm these open-label findings. [source]


Numerical investigation of the effect of inlet condition on self-excited oscillation of wet steam flow in a supersonic turbine cascade,

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 12 2009
Wu Xiaoming
Abstract Self-excited oscillation can be induced due to the interaction between condensation process and local transonic condition in condensing flow, which is an important problem in wet steam turbine. With an Eulerian/Eulerian numerical model, the self-excited oscillation of wet steam flow is investigated in a supersonic turbine cascade. Owing to supercritical heat addition to the subsonic flow in the convergent part of the cascade, the oscillation frequency decreases with increased inlet supercooling. Mass flow rate increases in the oscillating flow due to the greater supersaturation in condensation process, while the increase will be suppressed with the flow oscillation. Higher inlet supercooling leads to the fact that the condensation process moves upstream and the loss increases. Moreover, some predictions of oscillation effects on outflow angle and aerodynamic force are also presented. Finally, heterogeneous condensations with inlet wetness and periodic inlet conditions, as a result of the interference between stator and rotor, are discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source]


IgG binding kinetics to oligo B protein A domains on lipid layers immobilized on a 27,MHz quartz-crystal microbalance

JOURNAL OF MOLECULAR RECOGNITION, Issue 2 2007
Hideyuki Mitomo
Abstract Although molecular recognitions between membrane receptors and their soluble ligands have been analyzed using their soluble proteins in bulk solutions, molecular recognitions of membrane receptors should be studied on lipid membranes considering their orientation and dynamics on membrane surfaces. We employed Staphylococcal Protein A (SpA) oligo B domains with long trialkyl-tags from E. coli (LppBx, x,=,1, 2, and 5) and immobilized LppBx on lipid layers using hydrophobic interactions from the trialkyl-tag, while maintaining the orientation of B domain-chains on a 27,MHz quartz-crystal microbalance (QCM; AT-cut shear mode). The binding of IgG Fc regions to LppBx on lipid layers was detected by frequency decreases (mass increases) on the QCM. The maximum amount bound (,mmax), association constants (Ka), association and dissociation rate constants (k1 and k,1, respectively) were obtained. Binding kinetics of IgG to LppB2 and LppB5 were quite similar, showing a simple 1:1 binding of the IgG Fc region to the B domain, when the surface coverage of LppB2 and LppB5 on the lipid surface is low (1.4%). When LppB5 was immobilized at the high surface coverage of 3.5%, the complex bindings of IgG such as one IgG bound to one or two LppB5 on the membrane could be observed. IgG-LppB1 binding was largely restricted because of steric hindrance on lipid surfaces. This gives a suggestion why Protein A has five IgG binding domains. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Anomalous capacitance,voltage characteristics of Pt,AlGaN/GaN Schottky diodes exposed to hydrogen

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7-8 2010
Yoshihiro Irokawa
Abstract We have investigated the interaction of hydrogen with Pt-AlGaN/GaN Schottky barrier diodes (SBDs) using a low-frequency capacitance-voltage (C-V) technique. At a frequency of 1kHz, the C-V curve in hydrogen shifts toward negative bias values as compared with that in nitrogen. As the frequency decreases from 1kHz to 1Hz, the capacitance in hydrogen significantly increases and the fluctuations of the capacitance are observed. These C-V characteristics are quite anomalous and have not been reported yet, suggesting the formation of interfacial polarization which could be attributable to hydrogen-related dipoles. The fluctuation of the capacitance may be related to the alignment of the dipoles. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Kinetic Study of Phosphorylation-Dependent Complex Formation between the Kinase-Inducible Domain (KID) of CREB and the KIX Domain of CBP on a Quartz Crystal Microbalance

CHEMISTRY - A EUROPEAN JOURNAL, Issue 23 2004
Hisao Matsuno Prof.
Abstract We report quantitative analysis of peptide,peptide interactions on a 27 MHz quartz crystal microbalance (QCM) in aqueous solution. The KID (kinase-inducible domain) of transcription factor CREB (cyclic AMP response element binding protein) is known to interact with the KIX domain of coactivator CBP (CREB binding protein), facilitated by phosphorylation at Ser-133 of the KID. The KIX domain peptide (86,aa) was immobilized on the QCM gold electrode surface by means of a poly(ethylene glycol) spacer. Binding of the KID peptide (46,aa) to the KIX peptide was detected by frequency decreases (mass increases) of the QCM. Both maximum binding amount (,mmax) and association constants (Ka) obtained from the QCM measurements increased as a result of phosphorylation of Ser-133 of the KID peptide. The Ka values for KIX peptide to the phosphorylated (pKID) and unphosphorylated KID peptides were (93±2)×103 and (5±1)×103,M,1, respectively. This difference was explained by the dissociation rate constant (k,1) of the pKID being 20 times smaller than that of the KID, while association rate constants (k1) were independent of phosphorylation. [source]