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Universal Method (universal + method)
Selected AbstractsUniversal method for synthesis of artificial gel antibodies by the imprinting approach combined with a unique electrophoresis technique for detection of minute structural differences of proteins, viruses, and cells (bacteria).ELECTROPHORESIS, Issue 23 2006III: Gel antibodies against cells (bacteria) Abstract Artificial antibodies in the form of gel granules were synthesized from the monomers acrylamide and N,N'-methylenebisacrylamide by the imprinting method in the presence of Echerichia coli bacteria as template. The electrophoretic migration velocities of the gel antibodies (i),saturated with the antigen (Escherichia,coli MRE-600), (ii),freed of the antigen, and (iii),resaturated with bacteria, were determinated by electrophoresis in a rotating narrow-bore tube of 245,mm length and the 2.5 and 9.6,mm inner and outer diameters, respectively. Removal of bacteria from the gel antibodies was made by treatment with enzymes, followed by washing with SDS and buffer. Gel granules becoming charged by adsorption of bacteria move in an electrical field. We obtained a significant selectivity of gel antibodies for E.,coli MRE-600, since the granules did not interact with Lactococcus lactis; and when E.,coli BL21 bacteria were added to the gels selective for E.,coli MRE-600, a significant difference in the migration rate of the complexes formed with the two strains was observed indicating the ability of differentiation between the two strains. The gel antibodies can be used repeatedly. The new imprinting method for the synthesis of artificial gel antibodies against bioparticles described herein, and the classical electrophoretic analysis technique employed, thus represent , when combined , a new approach to distinguish between different types and strains of bacteria. The application area can certainly be extended to cover other classes of cells. [source] In Situ Bioconjugation: Single Step Approach to Tailored Nanoparticle-Bioconjugates by Ultrashort Pulsed Laser AblationADVANCED FUNCTIONAL MATERIALS, Issue 8 2009Svea Petersen Abstract A single step approach to tailored nanoparticle-bioconjugates, enabling the generation of gold nanoparticles by laser ablation and their in situ conjugation with any biomolecule bearing an electron donating function (e.g., thiolated oligonucleotides) is established. The integrity of oligonucleotides after conjugation and the stability of bioconjugates in physiological media are investigated. Their size is tailorable via process parameters. This rapid and universal method may provide biochemists with various nanoparticle-bioconjugates for screening the often unpredictable structure,function relationship. [source] Higher order explicit time integration schemes for Maxwell's equationsINTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 5-6 2002Holger Spachmann Abstract The finite integration technique (FIT) is an efficient and universal method for solving a wide range of problems in computational electrodynamics. The conventional formulation in time-domain (FITD) has a second-order accuracy with respect to spatial and temporal discretization and is computationally equivalent with the well-known finite difference time-domain (FDTD) scheme. The dispersive character of the second-order spatial operators and temporal integration schemes limits the problem size to electrically small structures. In contrast higher-order approaches result not only in low-dispersive schemes with modified stability conditions but also higher computational costs. In this paper, a general framework of explicit Runge,Kutta and leap-frog integrators of arbitrary orders N is derived. The powerful root-locus method derived from general system theory forms the basis of the theoretical mainframe for analysing convergence, stability and dispersion characteristics of the proposed integrators. As it is clearly stated, the second- and fourth-order leap-frog scheme are highly preferable in comparison to any other higher order Runge,Kutta or leap-frog scheme concerning stability, efficiency and energy conservation. Copyright © 2002 John Wiley & Sons, Ltd. [source] Simulation-based learning in nurse education: systematic reviewJOURNAL OF ADVANCED NURSING, Issue 1 2010Robyn P. Cant Abstract Title.,Simulation-based learning in nurse education: systematic review. Aim., This paper is a report of a review of the quantitative evidence for medium to high fidelity simulation using manikins in nursing, in comparison to other educational strategies. Background., Human simulation is an educational process that can replicate clinical practices in a safe environment. Although endorsed in nursing curricula, its effectiveness is largely unknown. Review methods., A systematic review of quantitative studies published between 1999 and January 2009 was undertaken using the following databases: CINAHL Plus, ERIC, Embase, Medline, SCOPUS, ProQuest and ProQuest Dissertation and Theses Database. The primary search terms were ,simulation' and ,human simulation'. Reference lists from relevant papers and the websites of relevant nursing organizations were also searched. The quality of the included studies was appraised using the Critical Appraisal Skills Programme criteria. Results. Twelve studies were included in the review. These used experimental or quasi-experimental designs. All reported simulation as a valid teaching/learning strategy. Six of the studies showed additional gains in knowledge, critical thinking ability, satisfaction or confidence compared with a control group (range 7,11%). The validity and reliability of the studies varied due to differences in design and assessment methods. Conclusion. Medium and/or high fidelity simulation using manikins is an effective teaching and learning method when best practice guidelines are adhered to. Simulation may have some advantage over other teaching methods, depending on the context, topic and method. Further exploration is needed to determine the effect of team size on learning and to develop a universal method of outcome measurement. [source] The new adhesion prophylaxis membrane A-part®,From in vitro testing to first in vivo resultsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2009Bernd Martin Jaenigen Abstract Introduction: Formation of postoperative intra-abdominal adhesions is a severe problem in surgery. Apart from standard surgical procedures, a variety of different substances is available to prevent adhesions, but no universal method has been developed so far. A membrane consisting of polyvinyl alcohol (PVA) and carboxymethylcellulose (CMC) has been demonstrated to be antiadhesive. Here, the in vitro testing and first in vivo results in a rabbit sidewall model are reported. Materials and Methods: A-part® membrane contains a PVA/CMC mixture in a thickness of 40 ,m. The composition, dissolution, tensile strength, and elasticity were examined to characterize the membrane in vitro. Experiments in vivo were carried out using a ,rabbit sidewall model' in which a standardized peritoneal trauma was covered with a 5 × 6 cm A-part® membrane. Adhesion formation in A-part®-treated animals was compared with that in Adept® (15 mL/kg body weight) and untreated controls. Results: An 80/20 PVA/CMC mixture forms a stable, elastic, transparent membrane, which can easily be placed intraoperatively. The dissolution shows a half-life of about 2 weeks [day 15: (45.1 ± 4.9)% SD], which affords good adhesion protection during the initial critical phase of adhesion formation. In wet conditions, the membrane follows abdominal movements without tearing (tensile strength 5.0 ± 4.2 N/cm SD; elasticity 29.5%). In a rabbit sidewall model, A-part® membrane significantly reduced adhesion development by (83.1 ± 31.5)% SD compared with the control and the Adept group (p < 0.001). Conclusion: The properties of the A-part® membrane suggest that it may be useful as an antiadhesive in surgery. A-part® is effective in invivo testing as determined in a rabbit sidewall model. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009 [source] Fluorine-18 labelling of oligonucleotides: Prosthetic labelling at the 5,-end using the N -(4-[18F]fluorobenzyl)-2-bromoacetamide reagentJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 12 2003B. Kuhnast Abstract Labelled oligonucleotides are new imaging tools to study gene expression at the nucleic acid and protein levels. We have previously developed a universal method to label oligonucleotides at their 3,-end with radiohalogens and particularly with fluorine-18, the most widely used positron-emitter, t1/2: 109.8 min. Using the same strategy, we herein report the fluorine-18 labelling of oligonucleotides at their 5,-end. A 18-mer 2,O-methyl modified oligoribonucleotide, bearing a phosphorothioate group at its 5,-end, was conjugated to our fluorine-18-labelled reagent N -(4-[18F]fluorobenzyl)-2-bromoacetamide. The whole synthetic procedure yielded up to 1 GBq of fluorine-18-labelled oligonucleotide with a specific radioactivity of 37,74 GBq/,mol in 160 min. Copyright © 2003 John Wiley & Sons, Ltd. [source] DNA barcoding of stylommatophoran land snails: a test of existing sequencesMOLECULAR ECOLOGY RESOURCES, Issue 4 2009ANGUS DAVISON Abstract DNA barcoding has attracted attention because it is a potentially simple and universal method for taxonomic assignment. One anticipated problem in applying the method to stylommatophoran land snails is that they frequently exhibit extreme divergence of mitochondrial DNA sequences, sometimes reaching 30% within species. We therefore trialled the utility of barcodes in identifying land snails, by analysing the stylommatophoran cytochrome oxidase subunit I sequences from GenBank. Two alignments of 381 and 228 base pairs were used to determine potential error rates among a test data set of 97 or 127 species, respectively. Identification success rates using neighbour-joining phylogenies were 92% for the longer sequence and 82% for the shorter sequence, indicating that a high degree of mitochondrial variation may actually be an advantage when using phylogeny-based methods for barcoding. There was, however, a large overlap between intra- and interspecific variation, with assignment failure (per cent of samples not placed with correct species) particularly associated with a low degree of mitochondrial variation (Kimura 2-parameter distance < 0.05) and a small GenBank sample size (< 25 per species). Thus, while the optimum intra/interspecific threshold value was 4%, this was associated with an overall error of 32% for the longer sequences and 44% for the shorter sequences. The high error rate necessitates that barcoding of land snails is a potentially useful method to discriminate species of land snail, but only when a baseline has first been established using conventional taxonomy and sample DNA sequences. There is no evidence for a barcoding gap, ruling out species discovery based on a threshold value alone. [source] Closely spaced external standard: a universal method of achieving 5 ppm mass accuracy over the entire MALDI plate in axial matrix-assisted laser desorption/ionization time-of-flight mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 19 2003Eugene Moskovets Close deposition of the sample and external standard was used in axial matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) to achieve mass accuracy equivalent to that obtained with an internal standard across the entire MALDI plate. In this work, the sample and external standard were deposited by continuous deposition in separate traces, each approximately 200,,m wide. The dependence of the mass accuracy on the distance between the sample and standard traces was determined across a MALDI target plate with dimensions of 57.5,mm,×,57.0,mm by varying the gap between the traces from 100,,m to 4,mm. During acquisition, two adjacent traces were alternately irradiated with a 200-Hz laser, such that the peaks in the resulting mass spectra combined the sample and external standard. Ion suppression was not observed even when the peptide concentrations in the two traces differed by more than two orders of magnitude. The five peaks from the external standard trace were used in a four-term mass calibration of the masses of the sample trace. The average accuracy across the whole plate with this method was 5,ppm when peaks of the sample trace had signal-to-noise ratios of at least 30 and the gap between the traces was approximately 100,,m. This approach was applied to determining peptide masses of a reversed-phase liquid chromatographic (LC) separation of a tryptic digest of , -galactosidase deposited as a long serpentine trace across the MALDI plate, with accuracy comparable to that obtainable using internal calibration. In addition, the eluent from reversed-phase LC separation of a strong cation-exchange fraction containing tryptic peptides from a yeast lysate along with the closely placed external standard was deposited on the MALDI plate. The data obtained in the MS and MS/MS modes on a MALDI-TOF/TOF mass spectrometer were combined and used in database searching with MASCOT. Since the significant score is a function of mass accuracy in the MS mode, database searching with high mass accuracy reduced the number of false positives and also added peptides which otherwise would have been eliminated at lower mass accuracy (false negatives). Copyright © 2003 John Wiley & Sons, Ltd. [source] Ectopic Beats in Heart Rate Variability Analysis: Effects of Editing on Time and Frequency Domain MeasuresANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2001Mirja A. Salo M.Sc. Background: Various methods can be used to edit biological and technical artefacts in heart rate variability (HRV), but there is relatively little information on the effects of such editing methods on HRV. Methods: The effects of editing on HRV analysis were studied using R-R interval data of 10 healthy subjects and 10 patients with a previous myocardial infarction (Ml). R-R interval tachograms of verified sinus beats were analyzed from short-term (,5 min) and long-term (,24 hours) recordings by eliminating different amounts of real R-R intervals. Three editing methods were applied to these segments: (1) interpolation of degree zero, (2) interpolation of degree one, and (3) deletion without replacement. Results: In time domain analysis of short-term data, the standard deviation of normal-to-normal intervals (SDANN) was least affected by editing, and 30%-50% of the data could be edited by all the three methods without a significant error (< 5%). In the frequency domain analysis, the method of editing resulted in remarkably different changes and errors for both the high-frequency (HF) and the low-frequency (LF) spectral components. The editing methods also yielded in different results in healthy subjects and AMI patients. In 24-hour HRV analysis, up to 50% could be edited by all methods without an error larger than 5% in the analysis of the standard deviation of normal to normal intervals (SDNN). Both interpolation methods also performed well in the editing of the long-term power spectral components for 24-hour data, but with the deletion method, only 5% of the data could be edited without a significant error. Conclusions: The amount and type of editing R-R interval data have remarkably different effects on various HRV indices. There is no universal method for editing ectopic beats that could be used in both the time-domain and the frequency-domain analysis of HRV. A.N.E. 2001;6(1):5,17 [source] | |||||||||||||||||||