bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular advances in understanding social insect population structure
Authors: Crozier Ross H. , Oldroyd Ben P. , Tay W. Tek , Kaufmann Bernard E. , Johnson Rebecca N. , Carew Melissa E. , Jennings Kim M. 
Published: May 2005

AbstractSocial insects present many phenomena seen in all organisms but in more extreme forms and with larger sample sizes than those observable in most natural populations of vertebrates. Microsatellites are proving very much more informative than allozymes for the analysis of population biological problems, and prolifically polymorphic markers are fairly readily developed. In addition, the male‐haploid genetic system of many social insects facilitates genetic analysis. The ability to amplify DNA from sperm stored in a female's sperm storage device enables the determination of mating types long after the death of the short‐lived males, in addition to information on the degree of mixing of sperm from different males. Mitochondrial (mt) DNA sequences are also proving important, not only in phylogenetic studies but also in molecular population genetics, as a tracer of female movements. Mitochondrial markers have definitively shown the movement of females between colonies, challenging models giving exclusive primacy to kin selection as the explanation for multi‐queen colonies, in Australian meat ants,Iridomyrmex purpureus, and the arid‐zone queenless antRhytidoponerasp. 12. Microsatellite and mtDNA variation are being studied inCamponotus consobrinussugar ants, showing an unexpected diversity of complexity in colony structure, and microsatellites have shown that transfer of ants between nests of the weaver antPolyrhachis doddimust be slight, despite an apparent lack of hostility.
Analysis of carbohydrate deficient transferrin by capillary zone electrophoresis
Authors: Prasad Rajani , Stout Robert L. , Coffin David , Smith James 
Published: May 2005

AbstractWe report a capillary zone electrophoresis method to separate the various sialylated isoforms of transferrin. The separation is carried out under nondenaturing conditions and at basic pH. Under these conditions, transferrin exhibits two major and three minor peaks. Plasma samples from a population consuming varying amounts of alcohol at different intervals were studied. A cut‐off value of 3% carbohydrate deficient transferrin (CDT: disialo, monosialo, and asialo transferrin), results in a clinical sensitivity of 88% in a population consuming at least 70 g/day alcohol for a minimum of two weeks. The sensitivity dropped significantly in a population consuming less than 70 g/day. This confirms previous reports of CDT as a specific marker for significant and chronic use of alcohol. Capillary electrophoresis offers an alternative method with respect to analysis time and throughput in the clinical laboratory.
Simultaneous determination of S‐adenosylmethionine and S‐adenosylhomocysteine by capillary zone electrophoresis
Authors: Pañak Karina C. , Giorgieri Sergio A. , Díaz Luis E. , Ruiz Oscar A. 
Published: May 2005

AbstractA reproducible, rapid procedure for the simultaneous quantitative separation of S‐adenosylmethionine and S‐adenosylhomocysteine by capillary zone electrophoresis has been developed. Separations were performed by using an uncoated capillary of 60 cm effective length and 50 μm ID, 40 mM sodium phosphate buffer, pH 2.50, as background electrolyte solution, and 30 kV. On‐line detection was carried out at 254 nm. Under the conditions selected we resolved a standard solution containing S‐adenosylmethionine and S‐adenosylhomocysteine in a run time shorter than 8 min. A mass detection limit in the range of 10 fmol was achieved. Adenosyl‐L‐methionine, S[methyl‐3H] has also been assayed under the same experimental conditions. Other related compounds did not show interference, including those derived from the hydrolysis of S‐adenosylmethionine. The present method allows simultaneous determination of these compounds, which play an important role in many microbiological and enzymatic research studies.
Column technology in capillary electrophoresis and capillary electrochromatography
Authors: Pesek Joseph J. , Matyska Maria T. 
Published: May 2005

AbstractA review of column technology in capillary electrophoresis (CE) including wall modification processes and open tubular as well as packed column formats in capillary electrochromatography (CEC) are presented. There are many approaches which can be used to solve separation problems which provide higher efficiency and/or shorter analysis times in comparison to other chromatographic techniques. However, both CE and CEC are still relatively undeveloped in comparison to a more mature method such as high performance liquid chromatography (HPLC) and improvement in column technology is changing rapidly.
Polymeric separation media for capillary electrophoresis of nucleic acids
Authors: Sunada Wade M. , Blanch Harvey W. 
Published: May 2005

AbstractThe choice of polymer matrix for separating nucleic acids by capillary electro‐phoresis has often been arbitrary. However, considerable research in the area has led to a wealth of data exploring the key parameters of the polymer matrix that affect nucleic acid separations: polymer type, polymer molecular mass, polymer concentration, temperature, and buffer components and additives. Using this information, it is possible to use rational methods of choosing a good polymer matrix for a particular application. Further research into the properties of the mechanism of separation in polymer solutions, as well as the polymer matrix and other solution components will lead to even more efficient separations.
Chemiluminescence detection in capillary electrophoresis
Authors: Staller Tracy D. , Sepaniak Michael J. 
Published: May 2005

AbstractCapillary electrophoresis (CE) and related techniques yield highly efficient separations while requiring only minute amounts of sample. Thus, these techniques are amenable to analyses of complex samples in diverse matrices and in situations where sample is extremely limited. The constraints of on‐column detection generally result in poor detection limits and have reduced the overall application of CE. One logical approach to increased sensitivity in CE detection has been the development of chemiluminescence (CL)‐based detectors. The current state of post‐column detector development, CL applications, and limitations of the technique are reported herein.
Capillary electrophoretic enantioseparations using macrocyclic antibiotics as chiral selectors
Authors: Armstrong Daniel W. , Nair Usha B. 
Published: May 2005

AbstractMacrocyclic antibiotics are the newest class of chiral selector used in capillary electrophoresis (CE) enantioseparations. Two basic types of compounds have proven to produce useful enantioseparations. They are the ansa compounds and the glycopeptides. The ansa compounds best resolve basic or cationic racemates while the glycopeptides best resolve acidic or anionic analytes. The structure and use of these chiral selectors are discussed. The factors affecting separation and the separation mechanism are considered as well.
Analysis of antibiotics by capillary electrophoresis
Authors: Flurer Cheryl L. 
Published: May 2005

AbstractThe broad category of antibiotics encompasses some of the most widely prescribed pharmaceuticals in the world. As is the case with any pharmaceutical, an antibiotic must be characterized in terms of its potency or activity, and the presence and quantity of impurities. Additionally, any residue or metabolite that may be present as a result of its use must be monitored. Many capillary electrophoretic techniques have been utilized in the analysis of antibiotics, addressing the various aspects of their quantitation, profiling, and monitoring. Some of the more recent applications are summarized in this review article.
Adaptive classification of two‐dimensional gel electrophoretic spot patterns by neural networks and cluster analysis
Authors: Vohradský Jiří 
Published: May 2005

AbstractThe interpretation of two‐dimensional gel electrophoresis spot profiles can be facilitated by statistical and machine learning programs. Two different approaches to classification of spot profiles – cluster analysis and neural networks – are discussed. Neural networks for two different model patterns were designed and an algorithm for training of the net for the classification was developed. It was shown that the performance of neural networks is higher compared to cluster and principal component analysis. The possibility of combining both approaches into one process can increase reliability and speed of classification. Artificially created training sets with added random noise can be used for network training. The analysis was applied on the Streptomyces coelicolor developmental two‐dimensional (2‐D) gel database.
HSC‐2DPAGE and the two‐dimensional gel electrophoresis database of dog heart proteins
Authors: Dunn Michael J. , Corbett Joseph M. , Wheeler Colin H. 
Published: May 2005

AbstractA two‐dimensional gel electrophoresis database of dog (Canis familiaris) proteins is presented. The database contains 1212 protein spots which have been characterised in terms of their pI and Mr. This database has been integrated into the HSC‐2DPAGE database which is accessible on the Internet via the World Wide Web with the uniform resource location (URL): (http://www.harefield.nthames.nhs.uk/nhli/protein/index.html). Identifications for 80 of the protein spots have been obtained by visual cross‐matching with the human heart protein database in HSC‐2DPAGE (42 spots), N‐terminal microsequence analysis (25 spots) and peptide mass fingerprinting (20 spots). This database is being used in studies of alterations in protein expression in models of heart failure and heart disease.
Identification and characterization of heat shock protein 27 protein species in human myocardial two‐dimensional electrophoresis patterns
Authors: Scheler Christian , Müller Eva‐Christina , Stahl Joachim , Müller‐Werdan Ursula , Salnikow Johann , Jungblut Peter 
Published: May 2005

AbstractImmunostaining of heat shock protein 27 (Hsp27) protein species on two‐dimensional electrophoresis (2‐DE) gels with enhanced sensitivity yields 59 spots reacting with anti‐Hsp27 antibodies. Recombinant Hsp27 exists in 2‐DE as two major protein species which comigrate in the human myocardial pattern with Hsp27 spots C754 and D899 as defined in the heart high‐performance 2‐DE database (http://www.mdc‐berlin.de/∼emu/heart/). Preparative electrophoresis of human myocardial proteins and analysis of the enriched mass range 20–30 kDa by 2‐DE revealed eight protein spots (C438, C582, C658, C697, C754, C595, C750) from the human myocardial database and a new spot not previously detected on silver‐stained gels. These spots were identified as Hsp27 protein species by enzymatic in‐gel‐digestion and analysis by matrix assisted laser desorption‐ionization (MALDI) peptide mass fingerprinting and, in part, MALDI‐post source decay sequencing of single fragments. Possible post‐translational modifications were investigated: immunostaining tests with anti‐phospho‐serine/‐threonine/‐tyrosine antibodies, although positive for other myocardial proteins, were negative for presumed Hsp27 protein species; likewise, periodate‐glycostaining assays and biotinylation screening did not detect modifications in the investigated Hsp27 protein species.
Two‐dimensional electrophoretic analysis of myocardial proteins from lead‐exposed rabbits
Authors: Toraason Mark , Moorman William , Mathias Patty I. , Fultz Carla , Witzmann Frank 
Published: May 2005

AbstractDespite reported adverse effects, the cardiovascular toxicity of lead remains controversial. The purpose of the present study was to determine if low‐level subchronic exposure of rabbits to lead would produce detectable, concentration‐dependent changes in myocardial proteins. Lead was administered to male Dutch Belted rabbits as a lead acetate solution, adjusted weekly to achieve and maintain the target blood lead levels of 0, 20, 40, and 80 μg/dL for 15 weeks. Lead exposures did not affect heart or body weights. Myocardial cocentrations of lead at sacrifice were 58 ± 25, 69 ± 23, 102 ± 62, and 105 ± 37 ng/g. Of 808 individual proteins resolved by two‐dimensional electrophoresis (2‐DE) in ventricular homogenates, 162 had coefficients of variation < 20%. A number of proteins were tentatively identified based on coordinate positions homologous to other established 2‐DE patterns. Despite variable expression of some protein spots, none of the protein abundances analyzed were found to be significantly altered (P < 0.001) by the lead exposures studied. Therefore results show no detectable effect of a low‐body burden of lead on major myocardial proteins of the rabbit.
Capillary electrophoresis analysis of isomeric truxillines and other high molecular weight impurities in illicit cocaine
Authors: Lurie Ira S. , Hays Patrick A. , Casale John F. , Moore James M. , Castell David M. , Chan King C. , Issaq Haleem J. 
Published: May 2005

AbstractThe analysis of by‐products and impurities in illicit cocaine, including the isomeric truxillines, is important for derivation of both strategic and tactical intelligence. In the present study, various capillary electrophoresis techniques were investigated for this purpose. The use of the anionic β‐cyclodextrin sulfobutyl ether IV as a run buffer additive at pH 8.6 gave a good separation of the truxillines and similar high molecular weight impurities in less than eight minutes. These impurities were first isolated from the bulk cocaine matrix using liquid‐liquid extraction and size‐exclusion high performance liquid chromatography. There was a red shift in the UV spectra obtained for the truxillines using photodiode array (PDA) UV detection during CE analysis. This anomalous behavior is attributed to photo‐degradation of the truxillines during the PDA‐UV irradiation process. Laser‐induced fluorescence detection using a UV krypton/fluoride laser provided greater selectivity and sensitivity versus UV detection for certain uncharacterized high molecular weight impurities.
Analysis of multiplexed short tandem repeat (STR) systems using capillary array electrophoresis
Authors: Mansfield Elaine S. , Robertson James M. , Vainer Marina , Isenberg Alice R. , Frazier Rachael R. , Ferguson Karin , Chow ShiTse , Harris Dennis W. , Barker David L. , Gill Peter D. , Budowle Bruce , McCord Bruce R. 
Published: May 2005

AbstractThe profiling of polymorphic short tandem repeat (STR) markers is being applied to human identification, parentage testing and genetic mapping. Reliable genotyping of these markers is facilitated by polymerase chain reaction (PCR) amplification and high‐resolution electrophoretic separation. Capillary array electrophoresis (CAE) offers very rapid, high‐resolution separation of the amplified DNA and potential for automated sample processing not realized employing conventional slab‐gel electrophoresis. The use of CAE to type DNA samples amplified at 11 genetic loci in multiplex profiles is presented. Two sets totaling 208 samples were amplified in a multiplex fashion using AmpFlSTR‐Blue or AmpFlSTR‐Green I and analyzed in a blind study using CAE. With the exception of one sample, the CAE genotyping results were in complete agreement with results obtained using a single‐capillary system or two slab‐gel electrophoresis systems. The sample, genotype TH01 7/10, migrated similar to TH01 6.3/9.3 allele sizes, which suggested a potential band migration shift. The recommended approach to such an observation is to analyze the sample again. The sample was rerun and correct genotype verified. Allelic ladder samples were analyzed multiple times by CAE to determine sizing accuracy and precision. The sizing of over 240 allelic ladder samples vielded an average within‐run precision of ± 0.13 bp and between‐run precision of ± 0.21 bp for fragments up to 350 bp. The CAE protocols permit processing of up to 96 multiplex STR samples in under 70 min.
Electrophoretic applications of phycobiliproteins
Authors: Aráoz Rómulo , Lebert Michael , Häder Donat‐P. 
Published: May 2005

AbstractPhycobiliproteins are homologous chromoproteins which constitute the phycobilisomes, the light harvesting complexes of the photosynthetic apparatus in cyanobacteria, rhodophyta and cryptophyta. In the present work, phycocyanin (PC) and Phycoerythrin (PE) from a Nostoc species are proposed as protein markers for electrophoretic techniques. Phycocyanin is a blue‐colored phycobiliprotein; it carries phycocyanobilin as chromophoric group and is composed of two subunits, α and β, with Mr of 14000 and 17000, respectively. In contrast, the PE subunits, having a similar Mr of 21000, are deep rose chromoproteins and carry phycoerythrobilin residues. Both low molecular weight phycobiliproteins are also suitable for monitoring protien blotting and the focusing time of protein samples during isoelectric focusing as internal markers. The PE subunits which form a single broad band after sodium dodecyl sulfate‐polyacrylamide gel electrophoresis have different isoelectric points, and they form two visible bands when they reach their isoelectric point. The phycobilisomes constitute up to 50% of the total protein in cyanobacteria and their content in PC or PE can be up‐ or down‐regulated by using different light conditions (chromatic adaptation).
Double enzyme‐catalyzed microreactors using capillary electrophoresis
Authors: Zhao Dong S. , Gomez Frank A. 
Published: May 2005

AbstractThis work evaluates the concept of a double enzyme‐catalyzed microreactor using capillary electrophoresis (CE). Migrating in a capillary under electrophoresis conditions, plugs of substrate and two enzymes are injected separately in buffer and allowed to react. Extent of reaction and product ratios were subsequently determined by CE. This concept is demonstrated using two model systems: the conversion of adenosine triphosphate (ATP) to adenosine diphosphate (ADP) and adenosine monophosphate (AMP) by hexokinase (HK, EC 2.7.1.1) and apyrase (APY, EC 3.6.1.5), respectively, in the conversion of glucose to glucose‐6‐phosphate and inorganic phosphate, respectively, and the conversion of nicotinamide adenine dinucleotide, reduced form (NADH), to nicotinamide adenine dinucleotide (NAD) and back to NADH by lactate dehydrogenase (LDH, EC 1.1.1.27) and glucose‐6‐phosphate dehydrogenase (G6PDH, EC 1.1.1.49), respectively, in the conversion of pyruvate to lactate and glucose‐6‐phosphate (glc‐6‐P) to 6‐phosphogluconate, respectively. These procedures illustrate the use of the capillary as a double microreactor and the ease of quantitation of reaction products under conditions of electrophoresis.
Whole genome scan for habitat‐specific genes by signature‐tagged mutagenesis (minireview)
Authors: Hensel Michael 
Published: May 2005

AbstractLarge numbers of new open reading frames can be identified by whole genome sequencing of microbial genomes. Efficient new approaches are required to investigate the role of the putative genes, or to identify genes required in distinct habitats. The novel technique ‘signature‐tagged mutagenesis’ allows the identification of individual mutants within complex pools of mutants. Large numbers of mutants can be analyzed in a parallel manner for negative phenotypes like loss of function or attenuation of virulence. Further analysis of mutations identified by a negative selection procedure can be performed by linking the position of the respective mutations to genes identified by whole genome sequencing of microbes.
A peptide concentration and purification method for protein characterization in the subpicomole range using matrix assisted laser desorption/ionization‐postsource decay (MALDI‐PSD) sequencing
Authors: Gevaert Kris , Demol Hans , Sklyarova Tatyana , Vandekerckhove Joël , Houthaeve Tony 
Published: May 2005

AbstractWe here describe the use of added reversed‐phase chromatographic beads to concentrate peptides from highly diluted solutions. In the procedure developed, peptide‐bead suspensions are dried under vacuum to complete dryness; peptides are subsequently eluted in a small volume of matrix‐assisted laser desorption/ionization (MALDI)‐matrix containing organic/aqueous solvent and transferred to a MALDI‐target for mass analysis. We show that by using this bead‐peptide concentration procedure, low femtomole amounts of peptides are efficiently concentrated, up to 1000 times, to volumes smaller than 0.7 μuL. We have used this concentration procedure in combination with MALDI‐post‐source decay analysis to identify subpicomole amounts of proteins present in polyacrylamide gels. Furthermore, we show that the bead‐peptide concentration method can be elegantly used to clean up samples contaminated with high concentrations of substances normally deleterious to MALDI‐mass spectrometry (MS) experiments. We have found additionally that the bead‐peptide concentration procedure can be successfully used to store low femtomole amounts of peptide for prolonged periods of time without severe losses of peptide material. This bead‐peptide concentration procedure therefore seems to be a simple and convenient step in the MALDI‐MS sample preparation process.
Use of liquid chromatography‐electrospray ionization‐tandem mass spectrometry (LC‐ESI‐MS/MS) for routine identification of enzymatically digested proteins separated by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis
Authors: Stone Kathryn L. , Deangelis Raymond , LoPresti Mary , Jones Joshua , Papov Vladimir V. , Williams Kenneth R. 
Published: May 2005

AbstractAutomated liquid chromatography‐electrospray ionization‐tandem mass spectrometry (LC‐ESI‐MS/MS) analysis of >100 tryptic digests carried out on sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) separated, Coomassie Blue‐stained proteins that were prepared by >50 different laboratories demonstrates that a commercial electrospray/quadrupole ion trap mass spectrometer and the tandem mass correlation algorithm developed by Eng et al. (Am. Soc. Mass Spectrom. 1994, 5, 976–989) provide an extremely robust and facile approach to routine protein identification. By requiring a minimum of two significant matches to peptides that would be predicted to be produced by the protease that was used, low pmol levels of proteins can be identified with high confidence while minimizing the probability of identifying the protease itself and/or the ubiquitous contaminant, keratin. Hence, in only 7% of the digests analyzed was keratin identified and in only 5% of the digests analyzed was the protease itself identified. In contrast, 58% of the analyzed samples were identified and, in many instances, multiple proteins were identified in the same sample. Although the median amount of digest analyzed was 6.1 pmol, the limit of sensitivity (as the instrument is configured with a flow rate of 4 μL/min) appears to be at the 500 fmol level. Since one of the primary reasons for not identifying a sample is that its sequence is not yet in the database searched, the utility of an LC MS/MS approach to protein identification will certainly increase in the future as the sequences of more genomes are completed.
High‐resolution density gradient electrophoresis of subcellular organelles and proteins under nondenaturing conditions
Authors: Tulp Abraham , Fernandez‐Borja Mar , Verwoerd Desirée , Neefjes Jacques 
Published: May 2005

AbstractWe have developed a density gradient electrophoresis device (DGE) and used it for the preparative separation of various endocytic organelles that are hard to separate by other means. Our separation by DGE of late endosomal vesicles, recycling vesicles, early endosomes and plasma membranes is unmatched. Using the same DGE device, we performed preparative high‐resolution rate zonal separation of proteins using amphoteric buffers as originally described by Bier (Electrophoresis 1993, 14, 1011–1018). Isoforms of bovine β‐lactoglobulin, human apo‐transferrin, and bovine erythrocyte carbonic anhydrase that have isoelectric points within 0.8 pH units were readily separated even in the absence of nonionic detergents. The DGE apparatus is inexpensive and has unique separation abilities for vesicles and proteins.