bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct and Cytochrome c Mediated Electrochemistry of Bilirubin Oxidase on Gold
Authors: Dronov Roman , Kurth Dirk G. , Scheller Frieder W. , Lisdat Fred 
Published: June 2007

AbstractDirect electron transfer (DET) of bilirubin oxidase from Myrothecium verrucaria (BOD) was established on promoter‐modified gold electrodes. The electrochemical behavior of the enzyme in solution was studied by means of cyclic voltammetry evaluating the biocatalytic reduction of dioxygen. The reaction of BOD at Au electrodes was shown to be efficient only at low pH. In addition, a novel interaction between BOD and cytochrome c (cyt.c) was found. It was shown that BOD efficiently accepts cyt.c as an electron donor in both cases when cyt.c is in solution and electrostatically adsorbed. The results suggest that cyt.c can play the role of a mediator facilitating electron transfer in a pH range where no DET could be observed between the enzyme and the electrode. For the interaction between cyt.c and BOD in solution the reaction kinetics has been studied electrochemically and spectrophotometrically.
Direct fluorometric detection of paramagnetic and heavy metal ions at sub‐amol level using an aromatic polyaminocarboxylate by CZE: Combination of pre‐ and on‐capillary complexation technique
Authors: Saito Shingo , Suzuki Ryouji , Danzaka Naoki , Hikichi Atsushi , Yoshimoto Keitaro , Maeda Mizuo , Aoyama Masakazu 
Published: June 2007

AbstractThe low sensitivity of simple CZE for detecting metal ions is a long‐standing problem even when an LIF detection system is employed. We have successfully achieved an ultrasensitive CE‐LIF using a simple CZE mode (typical detection limit: 10−11–10−10 mol/dm3). Both the design of a newly synthesized ligand and the combination of a precapillary derivatizing technique with an on‐capillary ternary complexing technique have enabled us to achieve this extremely low LOD and high resolution of large metal complexes. The direct fluorescent detection of the paramagnetic metal ions was achieved for the first time despite their intrinsic fluorescent quenching nature. The fluorescent ligand (L) consists of a polyaminocarboxylate chelating moiety, a strongly emissive fluorescein moiety and a spacer connecting the two portions. The migration behavior of various metal–L complexes was investigated. The resolution among the complexes was improved by the introduction of a ternary complex equilibrium of the kinetically stable mother complexes with OH− ion. The analytical potential of our simple system was examined, and it was proved that the system was one of the most sensitive methods without the need for any preconcentration process.
CE characterization of potential toxic labile iron in colloidal parenteral iron formulations using off‐capillary and on‐capillary complexation with EDTA
Authors: Jahn Markus R. , Mrestani Yahya , Langguth Peter , Neubert Reinhard H. H. 
Published: June 2007

AbstractThe present study describes the application of CZE to investigate the portion of labile iron in the following parenteral formulations: iron gluconate, iron saccharate, and iron dextran. Labile iron was detected as Fe(III)‐chelate of EDTA at 246 nm. When EDTA was incubated with the formulations before electrophoresis, labile iron, or chelatable iron, respectively, was detected in all formulations, mostly in iron gluconate and iron saccharate. It was observed that the amount of iron released is time‐ and pH‐dependent. In contrast, when EDTA was separately injected before the formulation sharp peaks of the Fe(III)‐chelate were detected only after injection of iron gluconate. This type of labile iron can be described as “electrophoretically free” iron. CE provides thus a new method to characterize potential toxic, labile iron in parenteral iron formulations.
Parallel analysis of antimicrobial activities in microbial community by SSCP based on CE
Authors: Chung Joo Hee , Park Young Seoub , Kim Jin , Shin Gi Won , Nam Myung Hee , Oh Min‐Kyu , Kim Chan Wha , Jung Gyoo Yeol , Hyun Park Jin 
Published: June 2007

AbstractConventional antimicrobial activity analyses such as the broth dilution method and disk diffusion test are considerably demanding processes for new antimicrobial agent discovery and sensitive diagnosis of infectious diseases. Here, we developed a new antimicrobial activity analysis system using CE‐based SSCP (CE‐SSCP) combined with 16S rRNA gene‐specific PCR (PCR/CE‐SSCP). Using this method, the population change in the microbial community in response to specific antimicrobial agents could be quantified with a high sensitivity and accuracy from a small sample amount. Using a mixture of microorganisms comprising Escherichia coli, Corynebacterium glutamicum, Acinetobacter calcoaceticus, and Staphylococcus aureus as a model system, the linear correlation between the genomic DNA concentrations and peak areas in 16S rRNA gene‐specific PCR/CE‐SSCP was determined; consequently, quantification of cell concentrations could be demonstrated using this method. Compared to the minimum inhibitory concentration (MIC) values from the conventional broth dilution method, this new system provided almost the same MIC values for popular antimicrobial agents such as kanamycin, spectinomycin, and streptomycin. The results demonstrated that the newly developed method can be a substitute for the conventional antimicrobial analysis method and highlighted its high potential in the areas of new antimicrobial agent discovery and clinical diagnosis.
2‐DE using hemi‐fluorinated surfactants
Authors: Starita‐Geribaldi Mireille , Thebault Pascal , Taffin de Givenchy Elisabeth , Guittard Frederic , Geribaldi Serge 
Published: June 2007

AbstractThe synthesis of hemi‐fluorinated zwitterionic surfactants was realized and assessed for 2‐DE, a powerful separation method for proteomic analysis. These new fluorinated amidosulfobetaine (FASB‐p,m) were compared to their hydrocarbon counterparts amidosulfobetaine (ASB‐n) characterized by a hydrophilic polar head, a hydrophobic and lipophilic tail, and an amido group as connector. The tail of these FASB surfactants was in part fluorinated resulting in the modulation of its lipophilicity (or oleophobicity). Their effect on the red blood cell (RBC) membrane showed a specific solubilization depending on the length of the hydrophobic part. A large number of polypeptide spots appeared in the 2‐DE patterns by using FASB‐p,m. The oleophobic character of these surfactants was confirmed by the fact that Band 3, a highly hydrophobic transmembrane protein, was not solubilized by these fluorinated structures. The corresponding pellet was very rich in Band 3 and could then be solubilized by using a strong detergent such as amidosulfobetaine with an alkyl tail containing 14 carbon atoms (ASB‐14). Thus, these hemi‐fluorinated surfactants appeared as powerful tools when used at the first step of a two‐step solubilization strategy using a hydrocarbon homologous surfactant in the second step.
Fabrication and performance of fiber electrophoresis microchips
Authors: Chen Zhi , Zhang Luyan , Chen Gang 
Published: June 2007

AbstractA method based on the in situ polymerization of methyl methacrylate (MMA) has been developed for the rapid fabrication of a novel separation platform, fiber electrophoresis microchip. To demonstrate the concept, prepolymerized MMA molding solution containing a UV initiator was sandwiched between a poly(methyl methacrylate) (PMMA) cover plate and a PMMA base plate bearing glycerol‐permeated fiberglass bundles and was exposed to UV light. During the UV‐initiated polymerization, the fiberglass bundles were embedded in the PMMA substrate to form fiberglass‐packed microchannels. When the glycerol in the fiberglass bundles was flushed away with water, the obtained porous fiberglass‐packed channels could be employed to perform electrophoresis separation. Scanning electron micrographs (SEMs) and microscopic images offered insights into the fiber electrophoresis microchip. The analytical performance of the novel microchip has been demonstrated by separating and detecting dopamine and catechol in connection with end‐column amperometric detection. The fiber‐based microchips can be fabricated by the new approach without the need for complicated and expensive lithography‐based microfabrication techniques, indicating great promise for the low‐cost production of microchips, and should find a wide range of applications.
High‐throughput multiplex microsatellite marker assay for detection and quantification of adulteration in Basmati rice (Oryza sativa)
Authors: Archak Sunil , Lakshminarayanareddy V. , Nagaraju Javaregowda 
Published: June 2007

AbstractBasmati rice is a very special type of aromatic rice known world‐wide for its extra long grains and pleasant and distinct aroma. Traditional Basmati rice cultivars, confined to Indo‐Gangetic regions of the Indian subcontinent, are often reported to be adulterated with crossbred Basmati varieties and long‐grain non‐Basmati varieties in the export market. At present, there is no commercial scale technology to reliably detect adulteration. We report here a CE‐based multiplex microsatellite marker assay for detection as well as quantification of adulteration in Basmati rice samples. The single‐tube assay multiplexes eight microsatellite loci to generate variety‐specific allele profiles that can detect adulteration from 1% upwards. The protocol also incorporates a quantitative‐competitive PCR‐based analysis for quantification of adulteration. Accuracy of quantification has been shown to be ±1.5%. The experiments used to develop and validate the methodology are described.
Method validation of in vitro RNA transcript analysis on the Agilent 2100 Bioanalyzer
Authors: Sodowich Bruce I. , Fadl Irini , Burns Craig 
Published: June 2007

AbstractThe Agilent 2100 Bioanalyzer can characterize in vitro RNA transcripts for their integrity, purity, concentration, and size. The results are comparable to denatured agarose electrophoresis with ethidium bromide staining and UV spectrophotometry combined. In this report, we describe our strategy for validating this method following the International Conference on Harmonization guidelines. The assay has a linear range of quantitation between 500 and 25 ng/μL. Quantitation accuracy is within ±20% of measurements produced from spectrophotometry and sizing accuracy is within ±7% based on theoretical sizes. Concentration and sizing measurements within a single assay produce RSDs that are <10 and <2%, respectively, indicating good precision. The method also maintains a tolerable precision when altering operator, day, and reagent kit lot. The RSD for quantitation is ≤25 and <2% for sizing. The LOQ and LOD are 15.4 and 5.4 ng/μL based on experimentation, producing values similar to those specified by the manufacturer. The Bioanalyzer can differentiate between the RNA transcript and DNA contamination, and protein contamination quenches the RNA transcript signal. The effect of the ionic strength of the buffer on RNA analysis is also examined. Limitations of this method and future applications are discussed.
Integration of continuous‐flow sampling with microchip electrophoresis using poly(dimethylsiloxane)‐based valves in a reversibly sealed device
Authors: Li Michelle W. , Martin R. Scott 
Published: June 2007

AbstractHere we describe a reversibly sealed microchip device that incorporates poly(dimethylsiloxane) (PDMS)‐based valves for the rapid injection of analytes from a continuously flowing stream into a channel network for analysis with microchip electrophoresis. The microchip was reversibly sealed to a PDMS‐coated glass substrate and microbore tubing was used for the introduction of gas and fluids to the microchip device. Two pneumatic valves were incorporated into the design and actuated on the order of hundreds of milliseconds, allowing analyte from a continuously flowing sampling stream to be injected into an electrophoresis separation channel. The device was characterized in terms of the valve actuation time and pushback voltage. It was also found that the addition of sodium dodecyl sulfate (SDS) to the buffer system greatly increased the reproducibility of the injection scheme and enabled the analysis of amino acids derivatized with naphthalene‐2,3‐dicarboxaldehyde/cyanide. Results from continuous injections of a 0.39 nL fluorescein plug into the optimized system showed that the injection process was reproducible (RSD of 0.7%, n = 10). Studies also showed that the device was capable of monitoring off‐chip changes in concentration with a device lag time of 90 s. Finally, the ability of the device to rapidly monitor on‐chip concentration changes was demonstrated by continually sampling from an analyte plug that was derivatized upstream from the electrophoresis/continuous flow interface. A reversibly sealed device of this type will be useful for the continuous monitoring and analysis of processes that occur either off‐chip (such as microdialysis sampling) or on‐chip from other integrated functions.
Rapid desalting and protein recovery with phenol after ammonium sulfate fractionation
Authors: Wang Wei , Liu Quan‐Jun , Cui Hong 
Published: June 2007

AbstractAmmonium sulfate (AS) fractionation is often used in protein and enzyme purification; however, the resultant protein pellets have a high salt content and desalting by dialysis is required prior to next analysis. Here, we have developed a phenol‐based method for quick desalting and concentrating proteins after AS fractionation of complex olive leaf protein extract. After redissolving, AS precipitates were desalted with phenol extraction and the abundance of β‐glucosidase in each fraction was monitored with a specific antibody. The results of electrophoresis and Western blot showed the feasibility of the method. The method is quick and universal, and does not need much technique.Ammonium sulfate (AS) is the most common salt used to fractionate complex protein samples by step‐wise precipitation [1]. AS fractionation provides crude purification of proteins away from nonproteins and it is typically included in protein purification protocols. However, protein precipitates obtained from AS fractionation have a high salt content, and need to be desalted prior to the next analysis. One way to remove excess AS is by dialyzing protein samples against a buffer low in salt content. This works fine though time consuming. Additionally, after dialysis, it is often needed to concentrate dilute protein solutions because the analysis requires small volumes, such as in gel electrophoresis. Recent research in plant proteomics calls for a rapid method for desalting and protein recovery after AS fractionation.
Development of in‐tube solid‐phase microextraction coupled to pressure‐assisted CEC and its application to the analysis of propranolol enantiomers in human urine
Authors: Lin Bo , Zheng Ming‐Ming , Ng Siu‐Choon , Feng Yu‐Qi 
Published: June 2007

AbstractA successful hyphenation of in‐tube solid‐phase microextraction (SPME) and pressure‐assisted CEC (pCEC) was developed by installing a poly(methacrylic acid‐co‐ethylene glycol dimethacrylate) monolithic capillary to the six‐port valve in a CEC system. The device designed was appropriate for on‐line in‐tube SPME coupled to pCEC or μHPLC. The evaluation of this hyphenation was first carried out for in‐tube SPME‐μHPLC with analytical capillaries packed with 3 μm octadecyl silica (ODS). Theobromine (TB), theophylline (TP), and caffeine (CA) were chosen as model drugs for an easy comparison with the results obtained by in tube SPME‐HPLC. The detection limits of these three analytes were improved more than 100 times when compared with the direct analysis by μHPLC. Then in‐tube SPME‐pCEC with CEC capillaries packed with perphenylcarbamoylated β‐CD‐bonded silica particles was applied to the determination and analysis of propranolol enantiomers in human urine. Under optimal extraction and separation conditions, the experimental LODs were 4 and 7 ng/mL for (S)‐propranolol and (R)‐propranolol, respectively. The calibration curves showed good linearity for both (S)‐propranolol (R2 = 0.9997) and (R)‐propranolol (R2 = 0.9996) over the concentration range from 20 to 5000 ng/mL. Reproducibility of the method was also investigated with intra‐ and interday precisions lower than 10% for both enantiomers at different concentration levels.
Seismic fragility analysis: Application to simple linear and nonlinear systems
Authors: Kafali Cagdas , Grigoriu Mircea 
Published: June 2007

AbstractSeismic fragility of a structural, nonstructural and/or geotechnical system is the probability that a system response exceeds a critical value under seismic ground motions of specified intensities. Fragility curves are plots of system fragilities versus a scalar measure of seismic intensity. Traditionally, peak ground acceleration (PGA) has been used as an intensity measure. Recent studies show that pseudo‐spectral acceleration provides a superior measure of seismic intensity than PGA.It is shown that pseudo‐spectral acceleration may not be a satisfactory measure of seismic intensity for the fragility analysis of nonlinear systems, so that fragility curves based on pseudo‐spectral acceleration are not recommended for these systems. An alternative intensity measure based on two parameters, the earthquake moment magnitude m and the distance r from the seismic source to system site, is proposed for the fragility analysis of nonlinear systems. The relationship between a system probability of failure and (m, r) is called fragility surface. Findings are for single degree of freedom systems and synthetic
ground motion records. Copyright © 2007 John Wiley & Sons, Ltd.
A robust interference cancellation technique for DS‐UWB systems using fuzzy step size LMS algorithm
Authors: Cheng Chia‐Hsin , Wen Jyh‐Horng , Chen Yu‐Fan , Lin Jen‐Yung 
Published: June 2007

AbstractThis paper discusses a direct‐sequence ultra‐wideband (DS‐UWB) system that uses the least mean square (LMS) adaptive filter for interference cancellation. Compared to the conventional LMS (C‐LMS) algorithm, the fuzzy step size LMS (FSS‐LMS) algorithm which we propose can perform rapid convergence with a low steady‐state fluctuation error. The sequential partial update scheme is used in the proposed FSS‐LMS algorithm to reduce the system complexity without trading off the bit error rate (BER). Simulations are conducted to evaluate the convergence and tracking behaviour of the proposed LMS algorithm. The BER of the DS‐UWB system in a realistic UWB channel is also investigated. Copyright © 2007 John Wiley & Sons, Ltd.
Primary mediastinal B‐cell lymphoma
Authors: Boleti E , Johnson P W M 
Published: June 2007

AbstractPrimary mediastinal B‐cell lymphoma (PMBCL) is a sub‐type of the heterogeneous diffuse large B‐cell lymphoma category, and comprises approximately 5% of all non‐Hodgkin's lymphomas (NHL). It was first recognized as a distinct clinico‐pathologic entity 20 years ago, and recent work has further characterized specific molecular features. Gene expression profiling has suggested a partial overlap with nodular sclerosing Hodgkin lymphoma (HL), with which it shares some clinical features. The optimal management remains a matter of debate. There is uncertainty as to whether weekly alternating chemotherapy regimens may be more effective than CHOP, whether consolidation radiotherapy (RT) to the mediastinum is always required, whether PET scanning can be used to determine this, and whether the use of rituximab as part of initial therapy will change the answers to these questions. The International Extranodal Lymphoma Study Group (IELSG) 26 clinicopathologic study of PMBCL, which has recently opened, represents a first attempt to gather data prospectively on some of these issues. Copyright © 2007 John Wiley & Sons, Ltd.
Patients with bisphosphonates‐associated osteonecrosis of the jaw have reduced circulating endothelial cells
Authors: Allegra A , Oteri G , Nastro E , Alonci A , Bellomo G , Del Fabro V , Quartarone E , Alati C , De Ponte FS , Cicciù D , Musolino C 
Published: June 2007

AbstractOsteonecrosis of the jaws (ONJ) associated with the use of bisphosphonates is a newly described entity. To elucidate the mechanism leading to ONJ and to test the hypothesis that in patients with ONJ the bisphosphonates may interfere with endothelial cell proliferation, using flow cytometric analysis we evaluated the number of circulating endothelial progenitor cells (EPCs) and circulating endothelial cells (CECs) in eight patients with bisphosphonate treatment and osteonecrosis, eight multiple myeloma (MM) patients with bisphosphonates treatment without ONJ and five normal subjects. MM patients showed an increase of CD34+ cells with respect the control subjects and ONJ subjects. EPCs and CECs were higher in MM patients compared to controls and ONJ patients. ONJ patients showed a decrease of EPCs compared to control subjects while CECs were similar to the controls group. Our results seem to show the possibility that bisphosphonates could have a antiangiogenic effect and a suppressive effect on CECs of patients with ONJ. Copyright © 2007 John Wiley & Sons, Ltd.
Factors controlling nitrogen release from two forested catchments with contrasting hydrochemical responses
Authors: Christopher Sheila F. , Mitchell Myron J. , McHale Michael R. , Boyer Elizabeth W. , Burns Douglas A. , Kendall Carol 
Published: June 2007

AbstractQuantifying biogeochemical cycles of nitrogen (N) and the associated fluxes to surface waters remains challenging, given the need to deal with spatial and temporal variability and to characterize complex and heterogeneous landscapes. We focused our study on catchments S14 and S15 located in the Adirondack Mountains of New York, USA, which have similar topographic and hydrologic characteristics but contrasting stream nitrate ($\hbox{NO}_{3}^{-}$) concentrations. We characterized the mechanisms by which $\hbox{NO}_{3}^{-}$ reaches the streams during hydrological events in these catchments, aiming to reconcile our field data with our conceptual model of factors that regulate nutrient exports from forested catchments. Combined hydrometric, chemical and isotopic (δ$\hbox{NO}_{3}^{-}$) data showed that the relative contributions of both soil and ground water sources were similar between the two catchments. Temporal patterns of stream chemistry were markedly different between S14 and S15, however, because the water sources in the two catchments have different solute concentrations. During late summer/fall, the largest source of $\hbox{NO}_{3}^{-}$ in S14 was till groundwater, whereas shallow soil was the largest $\hbox{NO}_{3}^{-}$ source in S15. $\hbox{NO}_{3}^{-}$ concentrations in surface water decreased in S14, whereas they increased in S15 because an increasing proportion of stream flow was derived from shallow soil sources. During snowmelt, the largest sources of $\hbox{NO}_{3}^{-}$ were in the near‐surface soil in both catchments. Concentrations of $\hbox{NO}_{3}^{-}$ increased as stream discharge increased and usually peaked before peak discharge, when shallow soil water sources made the largest contribution to stream discharge. The timing of peaks in stream $\hbox{NO}_{3}^{-}$concentrations was affected by antecedent moisture conditions. By elucidating the factors that affect sources and transport of N, including differences in the soil nutrient cycling and hydrological characteristics of S14 and S15, this study contributes to the overall conceptualization of $\hbox{NO}_{3}^{-}$ release from temperate forested catchments. Copyright © 2007 John Wiley & Sons, Ltd.