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CE
Kinds of CE Terms modified by CE Selected AbstractsNew composites with high thermal conductivity and low dielectric constant for microelectronic packagingPOLYMER COMPOSITES, Issue 2 2010Wei Ling Three composites based on cyanate (CE) resin, aluminum nitride (AlN), surface-treated aluminum nitride [AlN(KH560)], and silicon dioxide (SiO2) for microelectronic packaging, coded as AlN/CE, AlN(KH560)-SiO2(KH560)/CE, and AlN-SiO2/CE composite, respectively, were developed for the first time. The thermal conductivity and dielectric constant of all composites were investigated in detail. Results show that properties of fillers in composites have great influence on the thermal conductivity and dielectric constant of composites. Surface treatment of fillers is beneficial to increase the thermal conductivity or reduce dielectric constant of the composites. Comparing with binary composite, when the filler content is high, ternary composites possess lower thermal conductivity and dielectric constant. The reasons leading to these outcomes are discussed intensively. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers [source] Influence of the prodrugs 5-fluorocytosine and CPT-11 on ovarian cancer cells using genetically engineered stem cells: tumor-tropic potential and inhibition of ovarian cancer cell growthCANCER SCIENCE, Issue 4 2010Ki-Yon Kim Recent studies have shown that genetically engineered stem cells (GESTECs) to produce suicide enzymes that convert non-toxic prodrugs to toxic metabolites selectively migrate toward tumor sites and reduce tumor growth. In the present study, we evaluated whether these GESTECs were capable of migrating to human ovarian cancer cells and examined the potential therapeutic efficacy of the gene-directed enzyme prodrug therapy against ovarian cancer cells in vitro. The expression of cytosine deaminase (CD) or carboxyl esterase (CE) mRNA of GESTECs was confirmed by RT-PCR. A modified transwell migration assay was performed to determine the migratory capacity of GESTECs to ovarian cancer cells. GESTECs (HB1.F3.CD or HB1.F3.CE cells) engineered to express a suicide gene (CD or CE) selectively migrated toward ovarian cancer cells. A [3H] thymidine incorporation assay was conducted to measure the proliferative index. Treatment of human epithelial ovarian cancer cell line (SKOV-3, an ovarian adenocarcinoma derived from the ascites of an ovarian cancer patient) with the prodrugs 5-fluorocytosine (5-FC) or camptothecin-11 (CPT-11) in the presence of HB1.F3.CD or HB1.F3.CE cells resulted in the inhibition of ovarian cancer cell growth. Based on the data presented herein, we suggest that GESTECs expressing CD/CE may have a potent advantage to selectively treat ovarian cancers. (Cancer Sci 2010; 101: 955,962) [source] Predictive Value of Admission Electrocardiography in Patients With Heart FailureCONGESTIVE HEART FAILURE, Issue 4 2008Karolina M. Zareba MD Admission electrocardiography (ECG) in heart failure (HF) patients provides important diagnostic information; however, there are limited data regarding the prognostic significance of ECG parameters for predicting cardiac events (CEs). The ECGs of 246 patients admitted with acute HF were evaluated for heart rate, rhythm, QRS and ST-T wave abnormalities, QTc duration, QT peak corrected (QTpc), T amplitude, and axis. The end points included rehospitalization for a CE or death during 30-day follow-up. There were 71 (29%) patients with CEs. In patients with CEs, atrial fibrillation (AF) was observed more frequently (27% vs 13%, respectively; P=.009) and QTpc was shorter (370±43 vs 386±44 ms, respectively; P=.020). Multivariate logistic regression analysis revealed that QTpc ,360 ms and AF were predictive of CE after adjustment for clinical covariates. In conclusion, apart from AF, the presence of short QTpc ,360 ms is independently associated with increased risk of rehospitalization or death in HF patients. [source] 10-year prevalence of contact allergy in the general population in Denmark estimated through the CE-DUR methodCONTACT DERMATITIS, Issue 4 2007Jacob Pontoppidan Thyssen The prevalence of contact allergy in the general population has traditionally been investigated through population-based epidemiological studies. A different approach is the combination of clinical epidemiological (CE) data and the World Health Organization-defined drug utilization research (DUR) method. The CE-DUR method was applied in Denmark to estimate the prevalence of contact allergy in the general population and compare it with the prevalence estimates from the Glostrup allergy studies. Contact allergy prevalence estimates ranging from very liberal (,worst case') to conservative (,best case') assumptions were based on patch test reading data in combination with an estimate of the number of persons eligible for patch testing each year based on sales data of the ,standard series'. The estimated 10-year prevalence of contact allergy ranged between 7.3% and 12.9% for adult Danes older than 18 years. The 10-year prevalence of contact allergy measured by CE-DUR was slightly lower than previous prevalence estimates from the Glostrup allergy studies. This could probably be explained by a decrease in nickel allergy. The CE-DUR approach holds the potential of being an efficient and easy monitoring method of contact allergy prevalence. [source] Why Christianity Happened: A Sociohistorical Account of Christian Origins (26,50 CE) , By James G. CrossleyCONVERSATIONS IN RELIGION & THEOLOGY, Issue 1 2009Lloyd Pietersen First page of article [source] Metabolism of high density lipoprotein apolipoprotein A-I and cholesteryl ester in insulin resistant dog: a stable isotope studyDIABETES OBESITY & METABOLISM, Issue 1 2007F. Briand Aims:, In reverse cholesterol transport (RCT), hepatic Scavenger Receptor class B type I (SR-BI) plays an important role by mediating the selective uptake of high-density lipoprotein cholesteryl ester (HDL-CE). However, little is known about this antiatherogenic mechanism in insulin resistance. HDL-CE selective uptake represents the main process for HDL-CE turnover in dog, a species lacking cholesteryl ester transfer protein activity. We therefore investigate the effects of diet induced insulin resistance on RCT. Methods:, Five beagle dogs, in healthy and insulin resistant states, underwent a primed constant infusion of [1,213C2]acetate and [5,5,5- 2H3]leucine, as labelled precursors of CE and apolipoprotein (apo) A-I, respectively. Data were analysed using modelling methods. Results:, HDL-apo A-I concentration did not change in insulin resistant state but apo A-I absolute production rate (APR) and fractional catabolic rate (FCR) were both higher (2.2- and 2.4-fold, respectively, p < 0.05). HDL-CE levels were lower (1.2-fold, p < 0.05). HDL-CE APR and FCR were both lower (2.3- and 2-fold, respectively, p < 0.05), as well as selective uptake (2.6-fold, p < 0.05). Conclusions:, Lower HDL-CE selective uptake suggests that RCT is impaired in obese insulin resistant dog. [source] Myocardial perfusion imaging and cardiac events in a cohort of asymptomatic patients with diabetes living in southern FranceDIABETIC MEDICINE, Issue 4 2006A. Sultan Abstract Aims, To assess the association between abnormal stress myocardial perfusion imaging (MPI) and cardiac events (CE) in asymptomatic patients with diabetes and with , 1 additional risk factor. Predictors of abnormal stress MPI were also evaluated. Methods, Four hundred and forty-seven consecutive patients who underwent stress MPI were prospectively followed for 2.1 [0.5,4.1] years for the subsequent occurrence of hard CE (myocardial infarction and sudden or coronary death) and soft CE (unstable angina and ischaemic heart failure requiring hospitalization). Re-vascularization procedures performed as a result of the screening protocol were not included in the analysis. Results, Follow-up was successful in 419 of 447 patients (94%), of whom 71 had abnormal MPI at baseline. Medical therapy was intensified in all subjects and especially in those with abnormal MPI. Twenty-three patients with abnormal MPI underwent a re-vascularization procedure. CEs occurred in 14 patients, including six of 71 patients (8.5%) with abnormal MPI and eight of 348 patients (2.3%) with normal MPI (P < 0.005). Only two patients developed a hard CE and 12 a soft CE. In multivariate analysis, abnormal MPI was the strongest predictor for CEs [odds ratio (OR) (95% CI) = 5.6 (1.7,18.5)]. Low-density lipoprotein cholesterol , 3.35 mmol/l [OR (95% CI) = 7.3; 1.5,34.7] and age > median [OR (95% CI) = 6.0 (1.2,28.6)] were additional independent predictors for CE. The independent predictors for abnormal MPI were male gender, plasma triglycerides , 1.70 mmol/l, creatinine clearance < 60 ml/min and HbA1c > 8%, with male gender the strongest [OR (95% CI) = 4.0 (1.8,8.8)]. Conclusions, Asymptomatic patients with diabetes in this study had a very low hard cardiac event rate over an intermediate period. This could be explained by the effects of intervention or by the low event rate in the background population. Randomized studies of cardiac heart disease screening are required in asymptomatic subjects with diabetes to determine the effectiveness of this intervention. Diabet. Med. (2006) [source] A cost-effectiveness analysis of four management strategies in the determination and follow-up of atypical squamous cells of undetermined significanceDIAGNOSTIC CYTOPATHOLOGY, Issue 2 2005Alice A. Hughes M.S.P.H. Abstract Atypical squamous cells of undetermined significance (ASC-US) are the most common abnormal cytological result on Papanicolaou (Pap) smear. We analyzed four management strategies in a hypothetical cohort of women divided by age group: (1) immediate colposcopy, (2) repeat cytology after an ASC-US Pap smear result, (3) conventional Pap with reflex human papillomavirus (HPV) testing, and (4) liquid-based cytology with reflex HPV testing. Parameter variables were collected from previously published data. Strategies that included reflex HPV testing had the lowest overall costs for all age groups combined. Repeat Pap smears had the highest number of true positive results throughout all stages but also had the uppermost number of missed cancers and highest costs. Immediate colposcopy had the second highest overall costs and detected fewer true positive results than liquid-based cytology. Younger women (aged 18,24 yr) consistently had higher total costs for all strategies investigated. Using the incremental cost-effectiveness (CE) ratio, the immediate colposcopy strategy was more costly and less effective than liquid-based cytology and, therefore, was dominated. The incremental CE ratio was lowest for liquid-based cytology compared with conventional cytology and liquid-based cytology with reflex HPV testing was the most cost-effective strategy. Diagn. Cytopathol. 2005;32:125,132. © 2005 Wiley-Liss, Inc. [source] MANAGEMENT OF OBSCURE GASTROINTESTINAL BLEEDING BASED ON THE CLASSIFICATION OF CAPSULE ENDOSCOPIC BLEEDING FINDINGSDIGESTIVE ENDOSCOPY, Issue 3 2010Mitsunori Maeda Background:, Double-balloon endoscopy (DBE) and capsule endoscopy (CE) have been useful in managing obscure gastrointestinal bleeding (OGIB). However, DBE is invasive, complex and time-consuming, therefore indications should probably be selective. The aim of this study was to evaluate the usefulness of the classification of the CE bleeding findings for determining the indications and timing of DBE in patients with OGIB. Methods:, From February 2003 to January 2009, 123 patients with OGIB who underwent CE were included in this study. These CE findings were classified based on the bleeding source. Type CE-I, II, III, IV and 0 indicate active bleeding, previous bleeding, lesions without active bleeding, a lesion outside of the small bowel, and no findings, respectively. We compared diagnostic yield and outcome between the classification and the findings of DBE or enteroclysis. Results:, Comparisons of the positive findings rate with DBE or enteroclysis, the treatment rate and the rebleeding rate with the classification showed: CE-Ia, 100% (6/6), 50% (3/6), 33.3% (2/6); Ib, 66.7% (4/6), 0% (0/6), 16.7% (1/6); IIa, 33.3% (1/3), 33.3% (1/3), 33.3% (1/3); IIb, 53.8% (7/13),15.4% (2/13), 30.8% (4/13); III, 100% (84/84), 9.5% (8/84), 8.3% (7/84); IV, 100% (2/2), 50% (1/2), 0% (0/2); and 0, 0% (0/9), 0% (0/9), 0% (0/9), respectively. Conclusions:, The proportion of patients requiring treatment, the positive findings rate with DBE or enteroclysis and the rebleeding rates tended to be higher in the higher ranked classification types (CE-I > II > III > IV > 0). These findings suggest that the classification can provide useful information on determining the indications and timing of DBE. [source] Evidence-based policy or policy-based evidence?DRUG AND ALCOHOL REVIEW, Issue 4 2007The role of evidence in the development, implementation of the Illicit Drug Diversion Initiative Abstract Issues. Evidence-based policy is promoted as the ideal in drug policy, yet public policy theorists suggest that policy-based evidence may be a more fitting analogy, where evidence is used selectively to support a predetermined policy direction. Approach. The following paper assesses the resonance of this notion to the development of the Illicit Drug Diversion Initiative (IDDI), an apparently pragmatic reform adopted in Australia in 1999 through the Federal Coalition ,Tough on Drugs' strategy. It utilises interviews with key informants from the Australian drug policy arena conducted in 2005 to assess the role of evidence in the design and implementation of the IDDI. Key Findings. The current paper shows that while policy-makers were generally supportive of the IDDI and viewed drug diversion as a more pragmatic response to drug users, they contend that implementation has suffered through a selective and variable emphasis upon evidence. Most notably, the IDDI is not premised upon best-practice objectives of reducing harm from drug use, but instead on ,Tough on Drugs' objectives of reducing drug use and crime. Implications. This paper contends that policy-based evidence may facilitate the adoption of pragmatic reforms, but reduce the capacity for effective reform. It therefore has both functional and dysfunctional elements. Conclusion. The paper concludes that greater attention is needed to understanding how to mesh political and pragmatic objectives, and hence to maximise the benefits from policy-based evidence. [Hughes CE. Evidence-based policy or policy-based evidence? The role of evidence in the development and implementation of the Illicit Drug Diversion Initiative. Drug Alcohol Rev 2007;26:363,368] [source] Demonstration of Left Ventricular Outflow Tract Eccentricity by Real Time 3D Echocardiography: Implications for the Determination of Aortic Valve AreaECHOCARDIOGRAPHY, Issue 8 2007Sanjay Doddamani M.D. Background: Determination of the left ventricular outflow tract cross-sectional area (ALVOT) is necessary for calculating aortic valve area (AVA) by echocardiography using the continuity equation (CE). In the commonly applied form of CE, ,r2 is used to estimate ALVOT utilizing the assumptions that LVOT is round and the parasternal long axis (PLAX) plane bisects LVOT. Imaging LVOT using real time 3D echocardiography (RT3DE) eliminates the need for these assumptions. We tested the hypothesis that LVOT is round based on a formula for eccentricity. Methods and Results: In 53 patients, 2D echocardiography (2DE) and RT3DE were acquired. ALVOT was calculated by 2DE using ,r2 (ALVOT-2D). Using RT3DE, ALVOT planimetry was performed immediately beneath the aortic valve (ALVOT-3Dplan). Eccentricity Index (EI) was calculated using the shortest and longest LVOT diameters. The long axis was measured to be larger by 0.53 cm ± 0.36 (P < 0.005). The median EI was 0.20 (0.00,0.54), indicating that half the subjects had at least a 20% difference between the major and minor diameters. ALVOT-3Dplan was larger than ALVOT-2D (3.73 ± 0.95 cm2 vs. 3.18 ± 0.73 cm2; P < 0.001) by paired analysis. Using the equation of an ellipse (,ab), ALVOT-3Dellip was 3.57 ± 0.95 resulting in improved agreement with ALVOT-3Dplan. Conclusions: In our small patient sample with normal aortic valves, we showed the LVOT shape is usually not round and frequently, elliptical. Incorrectly assuming a round LVOT underestimated the ALVOT-3Dplan and consequently the AVA by 15%. Investigating the LVOT in aortic stenosis is warranted to evaluate whether RT3DE may improve measurement of AVA. [source] Separation and Detection of Nitrophenols at Capillary Electrophoresis Microchips with Amperometric DetectionELECTROANALYSIS, Issue 2 2006Jan Fischer Abstract A miniaturized analytical system for the separation and amperometric detection of toxic nitrophenols, based on the coupling of a micromachined capillary electrophoresis (CE) chip with a glassy carbon detector is described. This microsystem enables a rapid (120,s/sample) simultaneous determination of five priority nitrophenolic pollutants (2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, and 2-methyl-4,6-dinitrophenol). These compounds can be detected down to the 1×10,5,M level using a 15,mM phosphate buffer pH,7.2 (containing 1.3,mM ,-cyclodextrin) as running solution on 77,mm long microchannel by applying a separation voltage of 3000,V and a negative potential of ,0.7,V (vs. Ag /AgCl wire). Applicability to ground water samples was demonstrated. [source] Coupling Capillary Electrophoresis and Pulsed Electrochemical DetectionELECTROANALYSIS, Issue 13 2005Carlos Abstract Pulsed electrochemical detection (PED) is an excellent method for detection of analytes that normally foul electrodes. In PED, the detection electrode is first cleaned at a high positive potential, then reactivated at a negative potential dissolving the surface oxide, and finally used to oxidize the analyte at a moderate positive potential. Due to the advantages and versatility of PED, many different variations of the detection waveform can be found in literature. This review focuses on application of PED to CE and in particular, the most commonly used modes: pulsed amperometric detection (PAD) and integrated pulsed amperometric detection (iPAD). [source] Electrochemical Detection for Capillary Electrophoresis Microchips: A ReviewELECTROANALYSIS, Issue 13 2005Joseph Wang Abstract Electrochemistry detection offers considerable promise for capillary-electrophoresis (CE) microchips, with features that include remarkable sensitivity, portability, independence of optical path length or sample turbidity, low cost and power requirements, and high compatibility with modern micromachining technologies. This article highlights key strategies in controlled-potential electrochemical detectors for CE microchip systems, along with recent advances and directions. Subjects covered include the design of the electrochemical detection system, its requirements and operational principles, common electrode materials, isolation from the separation voltage, derivatization reactions, typical applications, and future prospects. It is expected that electrochemical detection will become a powerful tool for CE microchip systems and will lead to the creation of truly portable (and possibly disposable) devices. [source] Enantioselective Recognition of Aspartic Acids by Chiral Ligand Exchange PotentiometryELECTROANALYSIS, Issue 11 2004Yanxiu Zhou Abstract Enantioselective resolution is realized by combining potentiometry with ligand exchange (CE) in a new method called chiral ligand exchange potentiometry (CLEP). A chiral selector, N -carbobenzoxy- L -aspartic acid (N-CBZ-L-Asp), preferentially recognizes D -aspartic acid (D-Asp) and undergoes ligand exchange with the enantiomeric labile coordination complexes of [Cu(II)(D-Asp)2] or [Cu(II)(L-Asp)2] to form a diastereoisomeric complex [(D-Asp)Cu(II)(N-CBZ-L-Asp)] (a) or [(L-Asp)Cu(II)(N-CBZ-L-Asp)] (b). Considerable stereoselectivity occurs in the formation of these diastereoisomeric complexes, and their net charges were ,2 (a) and 0 (b), respectively, resulting in different Nernst factor (electrode slope), thus enabling chiral D-Asp to be distinguished by potentiometry without any pre- or postseparation processes. [source] Microfluidic chip-capillary electrophoresis for two orders extension of adjustable upper working range for profiling of inorganic and organic anions in urineELECTROPHORESIS, Issue 18 2010Wen Peng Guo Abstract To meet the need for onsite monitoring of urine anions, a microfluidic chip-capillary electrophoresis device was designed, fabricated and tested to extend the upper CE working range for an enhancement up to 500 fold (100 fold for sample dilution and 5 folds for CE injection) in order to analyze highly variable anionic metabolites in urine samples. Capillaries were embedded between two PMMA plates with laser-fabricated microchannel patterns to produce the microfluidic chip-capillary electrophoresis to perform standard/sample dilution and CE injection with adjustable dilution ratios. A circular ferrofluid valve was incorporated on-chip to perform cleanup and conditioning, mixing and dilution, injection and CE separation. Under optimized conditions, a complete assay for four samples can be achieved within an hour for 15 anions commonly found in urines. Satisfactory working ranges (0.005,500,mM) and low detection limits (0.5,6.5,,M based on S/N =2) are obtained with satisfactory repeatability (RSD, n=5) 0.52,0.87% and 4.1,6.5% for migration time and peak area, respectively. The working ranges with two orders adjustable upper extension are adequate to cover all analytes concentrations commonly found in human urine samples. The device fabricated shows sufficiently large experimentally verifiable enhancement factor to meet the application requirements. Its reliability was established by more than 94% recoveries of spiked standards and agreeable results from parallel method comparison with conventional ion chromatography method. The extension of the upper CE working range enables flexible onsite dilution on demand, a quick turn-around of results, and a low-cost device suitable for bedside monitoring of patients under critical conditions for metabolic disorders. [source] Cover Picture: Electrophoresis 16'2010ELECTROPHORESIS, Issue 16 2010Article first published online: 19 AUG 2010 Issue no. 16 is a regular issue with an Emphasis on "Proteins and Proteomics" comprising 20 manuscripts distributed over 4 separate parts. Part I has 7 research articles on various aspects of proteins and proteomics including combinatorial peptide ligand library for accessing low abundance proteins, analysis of membrane proteins, proteomic profiling of human colon cancer cells, quantitative determinations of biomarkers in clinical diagnostics, recombinant factor VIII, analysis of E. coli soluble proteins, and a weakly basic amino-reactive fluorescent label for IEF of proteins and chip electrophoresis. Part II has 2 research articles dealing with the CE analysis of magnetic nanoparticles and a microfluidic magnetic bead impact for cell stimulation. Part III consists of 2 research articles dealing with on-line preconcentration in CE. Instrumentation, devices and various methodologies are described in 9 research articles, which make the content of Part IV. Featured articles include: Combinatorial peptide ligand library plasma treatment: Advantages for accessing low-abundance proteins ((doi: 10.1002/elps.201000188)) Precautions to improve the accuracy of quantitative determinations of biomarkers in clinical diagnostics ((doi: 10.1002/elps.201000243)) Rapid identification of Candida albicans in blood by combined capillary electrophoresis and fluorescence in situ hybridization ((doi: 10.1002/elps.201000138)) [source] Microfluidic devices for electrokinetic sample fractionationELECTROPHORESIS, Issue 15 2010Zhen Wang Abstract We present three generations of microchip-based "in-space" sample fractionators and collectors for use in proteomics. The basic chip design consisted of a single channel for CE separation of analytes that then intersects a fractionation zone feed into multiple high aspect ratio microchannels for fractionation of separated components. Achievements of each generation are discussed in relation to important design criteria. CE-separated samples were electrokinetically driven to multiple collection channels in sequence without cross-contamination under the protection of sheath streams. A 36-channel fractionator demonstrated the efficacy of a high-throughput fractionator with no observed cross-contamination. A mixture of IgG and BSA was used to test the efficiency of the fractionator and collector. CE of the fractionated samples was performed on the same device to verify their purity. Our demonstration proved to be efficient and reproducible in obtaining non-contaminated samples over 15 sample injections. Experimental results were found to be in close agreement with PSpice simulation in terms of flow behavior, contamination control and device performance. The design presented here has a great potential to be integrated in proteomic platforms. [source] Analysis of amphetamine-type substances by capillary zone electrophoresis using capacitively coupled contactless conductivity detectionELECTROPHORESIS, Issue 15 2010Rochelle Epple Abstract CE with capacitively coupled contactless conductivity detection (C4D) was employed for the separation and detection of seven amphetamine analogues as well as amphetamine, dextroamphetamine, methamphetamine and 3,4-methylenedioxymethamphetamine. The separation electrolyte was 30,mM hydroxypropyl-,-cyclodextrin (HP,CD) in a 75,mM acetic acid+25,mM sodium acetate buffer adjusted to pH 4.55. Conductivity detection was compared with UV detection using this same electrolyte. Average detection limits for C4D and UV were 1.3 and 1.0,ppm, respectively. The effects of HP,CD concentration and BGE composition on the selectivity of the separation were also investigated. An illicit, street-grade sample of 3,4-methylenedioxymethamphetamine (Ecstasy) and a prescription dextroamphetamine tablet were also analysed. [source] Cover Picture: Electrophoresis 14'2010ELECTROPHORESIS, Issue 14 2010Article first published online: 21 JUL 2010 Issue no. 14 is a "mini special issue" on "Microscale Separation Methods for Metabolomics" comprising 9 manuscripts on metabolomics and 12 manuscripts on various topics in nucleic acids, biomarkers, proteomics, miniaturization, etc. Part I has 9 manuscripts on metabolomics featuring new technological developments and the potential of CE-MS, targeted analysis of one class of metabolites and non-targeted analysis, and data interpretation that is essential to acquire useful biological information. In short, the importance of CE and, generally, of microscale separation methods for metabolomics is rapidly increasing and the papers published in this issue give an overview of this field. Part II has 2 research papers on biomarkers while Part III is on various aspects of nucleic acids including but not limited to genotyping, PCR, SSCP, PCR and detection of DNA. Part IV describes various aspects of fundamentals and methodology in microfluidics, cell lysates by 2-DE, CE-LIF of plasmid DNA, whole blood assay of trypsin activity, etc. [source] Cover Picture: Electrophoresis 13'2010ELECTROPHORESIS, Issue 13 2010Article first published online: 30 JUN 2010 Issue no. 13 is a special issue on "Food and Beverage Analysis" comprising 23 contributions distributed over four distinct parts. Part I "presents six review papers, five of them are focused on the use of capillary electromigration techniques for detecting enantiomers, nucleosides, nucleotides, pesticides and contaminants in foods as well as foodborne pathogens". The sixth review deals with the application of two-dimensional electrophoresis to investigate food allergens. A series of original contributions on the use of CE, CEC and MEKC in the analysis of food constituents are grouped in Part II. Part III presents "Works on the detection of genetically modified foods by CGE and the analysis of antibiotics and antioxidants by microemulsion electrokinetic chromatography". Finally, Part IV is on the use of CE-MS to analyze endocrine disruptors and polyphenols in different food matrices, and on the speciation analysis of arsenic and selenium compounds in different foodstuffs by capillary electrophoresis-inductively coupled plasma-mass spectrometry. [source] Capillary electrophoresis for the analysis of contaminants in emerging food safety issues and food traceabilityELECTROPHORESIS, Issue 13 2010Belinda Vallejo-Cordoba Abstract This review presents an overview of the applicability of CE in the analysis of chemical and biological contaminants involved in emerging food safety issues. Additionally, CE-based genetic analyzers' usefulness as a unique tool in food traceability verification systems was presented. First, analytical approaches for the determination of melamine and specific food allergens in different foods were discussed. Second, natural toxin analysis by CE was updated from the last review reported in 2008. Finally, the analysis of prion proteins associated with the "mad cow" crises and the application of CE-based genetic analyzers for meat traceability were summarized. [source] Simultaneous determination of six non-polar heterocyclic amines in meat samples by supercritical fluid extraction,capillary electrophoresis under fluorimetric detectionELECTROPHORESIS, Issue 13 2010Fernando De Andrés Abstract A novel, sensitive and selective method for the separation and quantification of a group of non-polar heterocyclic amines (9H-pyrido-[3,4-b] indole, norharmane; 1-methyl-9H-pyrido-[3,4-b] indole, harmane; 2-amino-9H-pyrido-[2,3-b] indole, A,C; 2-amino-3-methyl-9H-pyrido-[2,3-b] indole, MeA,C; 3-amino-1,4-dimethyl-5H-pyrido-[4,3-b] indole, Trp-P-1 and 3-amino-1-methyl-5H-pyrido-[4,3-b] indole, Trp-P-2) in commercial meat samples has been developed. This methodology is faster than others previously described. The method is based on the combination of a supercritical fluid extraction procedure, followed by the analysis of the extracted plug by CE with fluorescence detection. The supercritical fluid extraction procedure was optimized for the clean-up of the samples and the extraction of the analytes. For the electrophoretic separation, the effect of composition, pH and concentration of buffer, organic modifier content, pressure and time of injection, capillary temperature and voltage applied were studied. A 10,mmol/L formic acid,ammonium formate,ACN (10%, v/v) solution at pH 1.5 was selected as the running electrolyte. With 5-s hydrodynamic injection, linear responses in the range from 100 to 1000,ng/mL and detection limits ranging from 15.9 to 28.1,ng/mL were obtained for different amines in less than 13,min. ACN,water (1:1 in volume) was used as a sample solvent. Fluorescence detection enhances the sensitivity and avoids interferences coming from non-fluorescent compounds present in the matrices of the sample extracts. [source] Cover Picture: Electrophoresis 12'2010ELECTROPHORESIS, Issue 12 2010Article first published online: 18 JUN 2010 Issue no. 12 is a regular issue comprising 19 contributions distributed over five distinct parts. Part I has 7 articles describing novel methodologies pertaining to proteins and proteomics. Part II has 3 research papers on CEC stationary phases and CEC-MS. Part III is on detection approaches including a review article on the advances and applications of chemiluminescence coupled to CE. Part IV has two papers on enantioseparations, and Part V has four contributions on aptamers, human genetic, preparative FFE and microchannels. Featured articles include: Simplified method for concentration of mitochondrial membrane protein complexes ((10.1002/elps.201000019)) Analysis of low-molecular mass aldehydes in drinking waters through capillary electrophoresis with laser-induced fluorescence detection ((10.1002/elps.200900734)) Selection of aptamers for signal transduction proteins by capillary electrophoresis ((10.1002/elps.200900543)) [source] Cover Picture: Electrophoresis 11'2010ELECTROPHORESIS, Issue 11 2010Article first published online: 26 MAY 2010 Issue no. 11 is a special issue on "Bioanalysis" comprising 18 manuscripts distributed over six distinct parts. Part I has 3 review articles describing a novel approach for biopolymer focusing, free flow electrophoresis and mass spectrometry analysis of deamidation of proteins. Part II has 2 research papers on some fundamentals and methodology. Part III is on microRNA while Part IV is on protein and protein complex analysis using CE and microfluidics. Part V, which is on gel based protein analysis and proteomic profiling, has 7 contributions making the bulk of the special issue. Finally, Part VI is on metabolic and toxicological profiling and has 3 contributions. [source] Cover Picture: Electrophoresis 10'2010ELECTROPHORESIS, Issue 10 2010Article first published online: 18 MAY 2010 Issue no. 10 is a regular issue comprising 19 manuscripts distributed over four distinct parts. Part I is on microfluidics and miniaturized systems and has 5 articles; Part II is on nucleic acids with 4 articles on restriction endonuclease fingerprinting, mutation detection and DNA separation and detection; Part III has 7 articles on monolithic stationary phases for CEC, single walled carbon nanohorns as pseudo-stationary phases for CEC and EKC, MEEKC, cyclodextrin-modified gold nanoparticles for enantioseparations by CEC, use of divalent dipeptides as counter ions in CE and capillary coating for CE of proteins; and Part IV has 3 articles on proteomics methodologies. Featured articles include: Microfluidic preparative free-flow isoelectric focusing in a triangular channel: System development and characterization ((10.1002/elps.200900577)) Separation and recovery of nucleic acids with improved biological activity by acid-degradable polyacrylamide gel electrophoresis ((10.1002/elps.200900783)) Evaluation of the performance of single-walled carbon nanohorns in capillary electrophoresis ((10.1002/elps.200900628)) The inter- and intra-operator variability in manual spot segmentation and its effect on spot quantitation in two dimensional electrophoresis analysis. ((10.1002/elps.200900674)) [source] Separation of amino alcohols using divalent dipeptides as counter ions in aqueous CEELECTROPHORESIS, Issue 10 2010Jakob Haglöf Abstract Divalent dipeptides have been introduced as counter ions in aqueous CZE. The dipeptides form ion pairs with amino alcohols in the BGE and facilitate the separation of amino alcohols. High concentrations of dipeptide caused reversed effective mobility for the analytes. The net charge of the dipeptide can be controlled using a buffer or a strong base, and regulates the interaction between the dipeptide and the amino alcohol. A stronger interaction and higher selectivity of amino alcohols was observed when the dipeptides were used as divalent counter ions, than in monovalent or uncharged form. Association constants for ion pairs between divalent dipeptides and amino alcohols can be used to enhance selectivity for amino alcohols in CZE. No chiral separation of amino alcohols was observed when using the dipeptides as ion-pairing chiral selectors in aqueous BGE, but addition of methanol to the BGE promoted enantioselectivity. [source] Synthesis of poly(N, N -dimethylacrylamide)- block -poly(ethylene oxide)- block -poly(N, N -dimethylacrylamide) and its application for separation of proteins by capillary zone electrophoresisELECTROPHORESIS, Issue 10 2010Jing Xu Abstract A series of well-defined triblock copolymers, poly(N, N -dimethylacrylamide)- block -poly(ethylene oxide)- block -poly(N, N -dimethylacrylamide) (PDMA- b -PEO- b -PDMA) synthesized by atom transfer radical polymerization, were used as physical coatings for protein separation. A comparative study of EOF showed that the triblock copolymer presented good capillary coating ability and EOF efficient suppression. The effects of the Mr of PDMA block in PDMA- b -PEO- b -PDMA triblock copolymer and buffer pH on the separation of basic protein for CE were investigated. Moreover, the influence of the copolymer structure on separation of basic protein was studied by comparing the performance of PDMA- b -PEO- b -PDMA triblock copolymer with PEO- b -PDMA diblock copolymer. Furthermore, the triblock copolymer coating showed higher separation efficiency and better migration time repeatability than fused-silica capillary when used in protein mixture separation and milk powder samples separation, respectively. The results demonstrated that the triblock copolymer coatings would have a wide application in the field of protein separation. [source] Cover Picture: Electrophoresis 9'2010ELECTROPHORESIS, Issue 9 2010Article first published online: 26 APR 2010 Issue no. 9 is a special issue on "CEC and EKC" comprising one "Fast Track" article and 21 articles distributed over two distinct parts. "Part I groups 13 contributions on enantioseparations in CE, CEC and capillary LC using various chiral selectors and their applications to a wide range of chiral species, while Part II assembles 8 papers on various methodological aspects and applications of EKC, CEC and CE". The "Fast Track" paper describes enhanced selectivity in CZE with multi-chiral selector systems. [source] Separation of propranolol enantiomers by CE using sulfated ,-CD derivatives in aqueous and non-aqueous electrolytes: Comparative CE and NMR study,ELECTROPHORESIS, Issue 9 2010Anne-Catherine Servais Abstract Separations using CE employing non-aqueous BGE are already as well established as separations in aqueous buffers. The separation mechanisms in achiral CE with non-aqueous BGEs are most likely similar to those in aqueous buffers. However, for the separation of enantiomers involving their interaction with chiral buffer additives, the interaction mechanisms might be very different in aqueous and non-aqueous BGEs. While the hypothesis regarding distinct mechanisms of enantiomer separations in aqueous and non-aqueous BGEs has been mentioned in several papers, no direct proof of this hypothesis has been reported to date. In the present study, the enantiomers of propranolol were resolved using CE in aqueous and non-aqueous methanolic BGEs with two single isomer sulfated derivatives of ,-CD, namely heptakis (2,3-diacetyl-6-sulfo)-,-CD and heptakis (2,3-dimethyl-6-sulfo)-,-CD. The enantiomer migration order of propranolol was inverted when an aqueous BGE was replaced with non-aqueous BGE in the case of heptakis (2,3-dimethyl-6-sulfo)-,-CD but remained the same in the case of heptakis (2,3-diacetyl-6-sulfo)-,-CD. The possible molecular mechanisms leading to this reversal of enantiomer migration order were studied by using nuclear overhauser effect spectroscopy in both aqueous and non-aqueous BGEs. [source] | |||||||||||||||||||||||||||||||