bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of amprolium in feed stuff by capiliary isotachophoresis
Authors: Křivánková Ludmila , Boček Petr 
Published: May 2005

AbstractA method for the determination of amprolium in feed stuff by analytical capillary isotachophoresis with column coupling is described. Up to 20 μl of the raw water extract of amprolium from a feed stuff can be analysed directly without any pretreatment in 15 min. The detection limit reached the level of ppm, the reproducibility of analyses in the followed range of 0.2–1.2 nmoles was 3 rel. %.
Two‐dimensional gel electrophoresis of low mobility group non‐histone proteins from myeloma cells
Authors: Bouchonneau Michel , Durand Jean Pierre , London Jacqueline , Pieri Jacques 
Published: May 2005

AbstractNon‐histone proteins (NHP) extracted from chromatin of two plasmocytoma cell lines, X63‐Ag8‐653 and Sp2/O‐Ag 14, with 0.35 M NaCl are analyzed by two‐dimensional polyacrylamide gel electrophoresis. These NHP have been fractionated into a high mobility group (HMG) and a low mobility group (LMG) using 2 % trichloroacetic acid (TCA). The HMG which is well‐characterized is soluble in 2 % TCA whereas the LMG precipitates. LMG resolubilization is difficult. Only a buffer containing glycerol, sodium dodecyl sulfate (SDS) and β‐mercaptoethanol enables them to be studied by polyacrylamide SDS electrophoresis. The LMG is clearly differentiated from the HMG by the predominance of high molecular weight proteins and by the high number of molecular species in a wide pH range. In the LMG there are also some diffrences between the two plasmocytoma cell lines. For example, a high molecular weight protein of 100 000 and pI 7.2–8.2 is present in Sp2/O‐Ag 14 but absent in X63‐Ag8–653. Also noticeable in the LMG proteins is the presence of low molecular weight proteins with high electrophoretic mobility.
Investigation of the stability of anionic isotachophoretic zones formed by ethylenediaminetetraacetic acid and nitrilotriacetic acid metal complexes
Authors: Thormann Wolfgang 
Published: May 2005

AbstractThe formation of anionic complexes with chelating ligands like ethylenediaminetetraacetic acid or nitrilotriacetic acid is useful for the anionic isotachophoretic determination of selected metals. A zone comprising such a metal complex may decompose gradually under the influence of the electric current. The kinetic behavior of various complex zones is determined in a capillary‐type apparatus with a linear array of 255 potential gradient sensors. The discussed examples comprise both systems where complex formation occurred in the sample solution prior to its injection into the isotachophoretic column and where an in situ formation of the complex took place under current flow.
Application of separator isoelectric focusing within the pH range 4‐6
Authors: Gill Peter 
Published: May 2005

AbstractSeparator isoelectric focusing is a simple technique for creating narrow pH gradients (less than 1 pH unit wide). It has proved useful elsewhere for the enhanced separation of phosphoglucomutase, esterase D, group specific component (Gc) haemoglobin, transferrin and for distinguishing between seminal and vaginal acid phosphatases. The properties of 10 different zwitterionic buffers have been studied in order to determine pH gradient profiles, their stability, experimental reproducibility and the effect of temperature. The effect of adding non‐ionic constituents (glycerol or sucrose) to the gel has also been investigated. The buffers examined produced narrow pH gradients within the pH 4–6 range. It was shown that specific pH gradients could be produced by mixing different buffers and carrier ampholytes together.
Negative aurodye for polyacrylamide gels: The impossible stain
Authors: Casero Patriza , del Campo Gian Battista , Righetti Pier Giorgio 
Published: May 2005

AbstractA negative aurodye for polyacrylamide gels has been developed. After isoelectric focusing in 6 % T polyacrylamide gels, protein fixation and washing, the gel is immersed in 0.01 % HAuCl4 containing 0.19 % citric acid and 0.1 % Tween 20, freshly made. The free reactants diffuse within the gel fibers and, upon micelle formation, stain the gel matrix purple, leaving white protein zones in sharp contrast. The sensitivity is of the order of 15–20 ng protein/mm2, matching and even passing that of silver stain (the lowest detection limit of Coomassie Blue being around 300 ng protein/mm2). The mechanism of background stain does not seem to depend on hydrophobic interaction with the gold‐detergent micelle, as polyacrylamide gelled with hydrophobic cross‐linkers has markedly decreased stain‐binding ability. The formation of mixed micelles of gold with non‐ionic, zwitterionic and anionic detergents has been studied.
Charge heterogeneity of human protein C revealed by isoelectric focusing in immobilized pH gradients
Authors: Gelfi Cecilia , Righetti Pier Giorgio , Mannucci Pier Mannuccio 
Published: May 2005

AbstractProtein C (PC), a plasma zymogen of a serine amidase with strong anticoagulant activity, has been purified to homogeneity as shown by sodium dodecyl sulfate electrophoresis. After isoelectric focusing in immobilized pH gradients, PC consists of six isobands, with isoelectric points (pI) between pH 4.8 and 5.1. That all the isobands were PC was confirmed by electroblotting on cellulose nitrate followed by immunoperoxidase staining. Activated PC gives a similar pattern of bands, with pIs ca. 0.5 units higher. Activated PC was also recognized by the monospecific antibody.
A new approach to crossed immunoelectrofocusing using polyacrylamide gel cylinders and agarose gel cassettes
Authors: Marshall Thomas 
Published: May 2005

AbstractA new approach for crossed immunoelectrofocusing is described. It combines isoelectric focusing in polyacrylamide gel cylinders and immunoelectrophoresis through vertical antibody‐containing agarose gels enclosed in glass cassettes. The approach, using the same apparatus as for high resolution two‐dimensional electrophoresis, has been successfully applied to human serum proteins and the effect of incorporating an antibody concentration gradient in the immunoelectrophoresis gels demonstrated.
Subtypes of the human complement component C3 revealed by isoelectric focusing in immobilized pH gradients
Authors: Charlionet Roland , Davrinche Christian , Rivat Claude 
Published: May 2005

AbstractThe phenotyping of the third component (C3) of human complement has been performed by isoelectric focusing in immobilized pH gradients followed by immunoblotting on nitrocellulose filter membrane. This powerful technique reveals variations of C3* and C3*F alleles not detected by agarose electrophoresis. The limits of the resolving power of isoelectric focusing in immobilized pH gradients for C3 analysis are shown to depend upon the high molecular weight of this protein. The notion of “suptypes” is discussed. Finally, the importance of subtyping for medical applications and for determination at the molecular level of interacting protein mechanisms is underlined.
The application of spread tissue isoelectric focusing for species' determination of raw muscle tissues
Authors: D'Andreay Alberto L. , Torres Leedham Verónica M. 
Published: May 2005

AbstractA routine method for species' determination of raw muscle tissues is described, Defrosted raw muscle tissues were evenly spread on filter paper applicators which were then placed on a thin‐layer agarose plate. A pH 4–8 gradient was obtained by mixing equal parts of Ampholine 4–6 and 6–8. Tissue homogenates of bovine, equine, porcine, ovine and other species were compared with spread tissue applications. The proposed method is useful in the routine control for quick identification of cut meat in cases of fraud where an exchange of species may have taken place.
Concentration of proteins in the free‐flow electrophoretic apparatus
Authors: Shukun Sergey A. , Gavryushkin Alexander V. , Brezgunov Vyacheslav N. , Zav'yalov Vladimir P. 
Published: May 2005

AbstractProtein concentration using step pH and conductivity gradients in a free‐flow electrophoretic apparatus is described. The experiments were carried out in a vertical planar 36.5 × 5.0 × 0.05 cm separation chamber with 48 channels both at the inlet and outlet. The gradients were generated by injecting a 2.5 mM borax solution (pH 9.2, conductivity = 0.5 mS) into the chamber via channels No. 1–12 counting from the cathode, and 0.45 M boric acid (pH 4.3, conductivity = 0.025 mS) together with the protein to be concentrated via the remaining channels. The gradients were suitable for the concentration of the proteins with isoelectric points ≥ pH 7.0 (human immunoglobulin G, bovine hemoglobin). From mixtures of hemoglobin and albumin, the latter was removed during concentration. The protein concentration of the starting solution does not affect the results of concentration. At constant current of 30 mA and a residence time of 45 s, the proteins were concentrated at a rate of 400 ml of starting solution per hour with a maximum concentration factor of 10.
Studies on the electrophoretic separation of the four common human phosphoglucomutase (PGM1) allozymes
Authors: Dissing Jørgen , Bär Walter 
Published: May 2005

AbstractThe electrophoretic properties of the four phosphoglucomutase (PGM1) allozymes were studied in the presence of different buffer constituents at pH values from 4.6 to 6.0. A separation of the allozymes allowing the identification of the 10 common phenotypes was obtained in the entire pH range. The separation of the “1+” and “1−” allozymes and of the “2+” and “2−” allozymes was poor near pH 6 but improved considerably at more acidic pH values. This indicated that the charge difference between the “1+” and the “1−” allozymes and between the “2+” and “2−” allozymes is due to substitution of a neutral amino acid in the “1+” and “2+” allozymes with histidine in the “1−” and “2−” allozymes. Above pH 5 the sequence from cathode to anode was “1−”,“1+”,“2−”,“2+” and below pH 5 it was “1−”,“2−”,“1+”,“2+”. At the lower pH values the separation between the “1−” and the “2−” allozymes and between the “1+” and the “2+” allozymes diminished. Hence only two PGM1 species may exist at more acidic pH (pH« 4.6): a “+” enzyme and a “−” enzyme. The presence of di‐ and polyvalent carboxylic acids in the electrophoretic buffer reduced the mobility of the enzymes towards the cathode or changed it into a migration towards the anode. This “buffer effect” was greatest with the polyvalent carboxylic acids. It is suggested that it is caused by an adsorption of carboxylate ions onto the enzyme surface, which results in a transfer of negative charges to the enzyme. The “buffer effect” varied slightly from one enzyme species to another, and this may explain the general experience that the electrophoretic resolution of a protein mixture differs when different buffer systems are used in the electrophoretic medium.
Improved horizontal two‐dimensional electrophoresis with hybrid isoelectric focusing in immobilized pH gradients in the first dimension and laying‐on transfer to the second dimension
Authors: Görg Angelika , Postel Wilhelm , Günther Siegfried , Weser Johann 
Published: May 2005

AbstractTwo‐dimensional (2‐D) maps obtained with horizontal or vertical electrophoretic systems are compared. There are no differences in resolution, spot size and distribution, but significant differences in handling, Horizontal 2‐D electrophoresis, where the equilibrated isoelectric focusing (IEF) gel strip with plastic backing is applied to the surface of the horizontal sodium dodecyl sulfate (SDS)‐gel, is extremely simple and easy to perform. Due to the optimal flat‐to‐flat contact of the two gels, no size or edge trimming of the gels, no agarose overlays nor embedding gels are needed. The influence of IEF, performed with carrier ampholytes, Immobilines or immobilized pH gradients (IPG) with carrier ampholytes, on 2‐D maps is demonstrated. More protein has migrated into the IPG gel with carrier ampholytes, displaying an increased number of spots.
The two‐dimensional pattern of cellular proteins from mitogen stimulated human peripheral blood lymphocytes
Authors: Waldinger Dorothea , Braun Andreas , Cleve Hartwig 
Published: May 2005

AbstractHuman peripheral blood lymphocytes were isolated from healthy donors and cultivated in the absence and presence of phytohemagglutinin (PHA) or pokeweed mitogen (PWM). Cell lysates of unlabelled lymphocytes or following stimulation of [H]leucine metabolically labelled lymphocytes were subjected to two‐dimensional electrophoresis. Differences in the protein patterns are described which are related to the method applied for visualization of the proteins (silver staining or fluorography), to the culture conditions (unstimulated, PHA or PWM stimulated lymphocytes) and to individual variations. Comparative analysis of the resulting patterns on silver stained gels and fluorograms revealed three qualitative and several quantitative differences. Comparing the two‐dimensional patterns of unstimulated and mitogenstimulated lymphocytes with silver staining, we recognized the quantitative increase of 6 protein spots after stimulation. Whereas protein patterns of PHA and PWM stimulated cells showed only minor quantitative differences when compared in silver stained gels, one qualitative and two quantitative differences between the two mitogens could be observed in fluorograms. Individual variability was generally low: within the approximately 30 unrelated individuals examined, thus far, the presence of two polymorphic proteins was demonstrated.
An improved procedure for polypeptide analysis of radiolabeled antigens resolved by crossed immunoelectrophoresis and its application to the study of inner and outer membranes of Escherichia coli
Authors: Owen Peter 
Published: May 2005

AbstractAn improved procedure is described for polypeptide analysis of radiolabeled antigens resolved by crossed immunoelectrophoresis (CIE). The method involves detection of immunoprecipitates by autoradiography of CIE gels dried onto filter paper. This modification allows selected segments of immunoprecipitate arcs to be excised with a high degree of precision. Radiolabeled antigens are extracted from excised precipitates by incubation at 60 °C in Laemmli sample buffer, and polypeptides are visualized by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis performed in conjunction with autoradiography or fluorography. Protein antigens of the bacterial outer membrane are shown to retain (in part) their properties of heat‐modifiability following drying and extraction, thus facilitating their identification. The procedure is applied to the analysis of fourteen membrane‐associated antigens of Escherichia coli and results in the identification of the ompF/C and the ompA gene products, and the resolution of two novel heterooligomeric outer membrane protein antigens. The polypeptide composition of four previously uncharacterized inner membrane antigens is also established. In addition, six antigens which had been characterized by other unrelated methods as common protein antigen, β‐galactosidase, adenosine‐5′‐triphosphatase, dihydrolipoyl dehydrogenase, D‐lactate dehydrogenase and the lpp gene product (the Braun lipoprotein) are shown to possess polypeptide profiles which confirm the initial identification. Evidence is also presented to support the thesis that the bound form of the lpp gene product can associate with other proteins of the outer membrane.
A practicallaboratory method for cell electrophoresis in an agarose sol
Authors: Gilman Robert L. 
Published: May 2005

AbstractThe method presented in this article was developed specifically to be used for the electrophoretic separation of biological cells. This method uses low cost materials and ordinary clinical laboratory electrophoresis equipment. Results are reasonably fast; time of migration was 20 min using a constant current setting of 6 mA for a single 3 × 4 inch gel tray. The use of SeaPlaque agarose sol at 40 °C allows the cells to migrate freely, while the solidification of the agarose at the end of the migration period fixes the cells in place on the plate. Samples can be taken from any position on the plate while the sol is still liquid. With this method, differences in rate of migration of erythrocytes from selected species of mammals were demonstrated. The method was developed using erythorcytes for samples and without staining of gels or prestaining of samples. Sample sizes of 2000 to 4000 cells gave easily visible bands. Band of cells from some species migrated as much as 40 mm. Separations were done in polystryrene gel tryays. This technique will be tested in the near future for the separation of the various types of blood cells and for separating other cell mixtures, e. g., bacteria.
Analytical control of the production of herbicides and growth regulators glyphosate and glyphosine by capillary isotachophoresis
Authors: Křivánková Ludmila , Boček Petr 
Published: May 2005

AbstractA method is described for direct analysis of the reaction mixtures of the production of the herbicide glyphosate and the growth regulator glyphosine by capillary isotachophoresis providing simultaneous determination of the products N‐phosphonomethyl‐glycine and N.N‐bis(phosphonomethyl)glycine as well as of all important reaction components ‐ sulfuric, formic, phosphorous, phosphoric, hydroxyacetic, nitrilotriacetic, iminodiacetic and N‐phosphonomethyliminodiacetic acids and glycine. The method is suitable for the analyses both of the final products and of mother liquors, where the maximum ratio of the concentrations ranges within 1:100. The time of analysis is dependent on the sample composition and ranges within 5–20 min. relative standard deviation of a single determination being less than 4 rel. %.
Utilization of highly repeated DNA sequences as a criterium of complete digestion on agarose gels: Example of human DNAs restricted by various endonucleases
Authors: Rahuel CÉCile , Dandieu Sylvie , Lucotte GéRard 
Published: May 2005

AbstractComparison between highly repeated DNA fragments of eucaryotic DNA digested by restriction endonucleases and the corresponding pattern of a completely digested DNA can be used as a criterium of complete digestion before the Southern blotting procedure. Results are presented for highly repeated fragments of human DNA, partially and completely restricted by six different endonucleases. Direct visualization of these fragments was obtained by ethidium bromide staining after agarose gel electrophoresis. Fragments corresponding to a complete DNA digestion were retained and can be used as reference.
Alpha‐amylase inhibitor in cereals: Comparison of the protein in different rye, wheat and triticale seeds by using immunoblotting
Authors: Sadowski Jan , Macgregor Alexander , Daussant Jean 
Published: May 2005

AbstractSeveral isoforms of the barley α‐amylase inhibitor were detected in the purified protein fraction and seed extract after isoelectric focusing. Polymorphism not detected by protein staining was revealed by immunoblotting using an antiserum against barley α‐amylase inhibitor. The antiserum, previously described as giving cross reactions with the inhibitors of rye and wheat, was used for comparing the electrophoretic patterns of the protein in several lines of rye, in several varieties of wheat and in different triticales. The antiserum was used for immunoblotting after isoelectric focusing at pH 3.5–10. The inhibitor was found in all samples but the degree of polymorphism was low. The same pattern was found for all lines of rye investigated. This pattern differed from the pattern found for wheat, but again, all cultivars of wheat investigated displayed similar patterns. Structural genes for the α‐amylase inhibitors were identified in the A and R genomes. Identical genes may exist on the B and D genomes. The wheat and rye structural genes for α‐amylase inhibitor were found to be expressed in the octoploid, hexaploid and tetraploid triticales.
Ionophoretic technique in the study of mixed ligand complexes (M‐nitrilotriacetate‐threoninate systems)
Authors: Singh Satyendra , Bajpai Arun K. , Tripathi Sita R. , Yadava Kanhaiya L. 
Published: May 2005

AbstractA novel ionophoretic technique for the study of complexes especially mixed ones has been described in the communications from this laboratory. Here with the help of this technique the stability constants of the complexes M‐nitrilotriacetate‐threoninates have been found to be 5.24, 5.01, 3.54 and 3.21, respectively.
Mitochondrial DNA in natural populations: An improved routine for the screening of genetic variation based on sensitive silver staining
Authors: Tegelström Håkan 
Published: May 2005

AbstractWhen screening natural populations for genetic variation in mitochondrial (mt) DNA it is necessary to screen as many individuals as possible for as large a number of base pairs as possible. This report describes a combination of laboratory techniques – isolation of mtDNA by either density ultracentrifugation or a phenol extraction procedure and DNA fragment visualization by a sensitive silver staining technique. These routines remove the major restriction of tissue sample size and number of individuals that can be screened and allows the investigation of at least 1000 base pairs from 1 g of tissue or 3–400 base pairs from 100 mg of frozen tissue.
Separation of serum cholinesterase molecular forms from three rodent species by gradient polyacrylamide gel electrophoresis
Authors: Bisso Guillermo M. 
Published: May 2005

AbstractGradient (5–30 %) polyacrylamide gel electrophoresis (PAGE) was used for the analysis of serum cholinesterases from the spiny mouse, the mouse and the rat. Enzymatic staining of slab gels was performed using acetylthiocholine as substrate. Eserine, 1.5‐bis(4‐allyldimethylammoniumphenyl)‐pentane‐3‐one dibromide (BW284C51) and tetraisopropylpyrophosphoramide (iso‐OMPA) were used as selective specific inhibitors of total, true and pseudo‐cholinesterase, respectively. Five main molecular forms were detected in the three species as sharp, well separated bands. All bands were inhibited completely by eserine while the effects of BW 284C51 and iso‐OMPA varied in the three species. This result suggests a common qualitative pattern for the three rodents with a different distribution of true and pseudo‐cholinesterase molecular forms for each species. The good resolution shown by the reported densitometric scan recordings confirms the advantages of gradient over homogeneous PAGE in the study of serum cholinesterases.
FXIIIA polymorphism in a Japanese population: Occurrence of FXIIIA*4 allele
Authors: Suzuki Koichi , Matsui Kiyoshi , Matsumoto Hideo 
Published: May 2005

AbstractThe FXIIIA polymorphism was studied in a Japanese population using agarose gel isoelectric focusing and agarose gel electrophoresis, combined with immunoblotting onto nitrocellulose membranes. The correspondence of patterns between the two methods was confirmed by two‐dimensional electrophoresis. A rare phenotype, FXIIIA 4–1, was detected in one individual besides the three common phenotypes FXIIIA 1, 2–1, and 2. This rare phenotype was identified with the originally reported FXIIIA 4–1 in Melanesians. Our results indicate the possibility that the FXIIIA*4 allele may be distributed widely in world populations.
Fast electrophoresis in superposed agarose minigels for DNA topoisomerase assays
Authors: Hamelin Claude , Yelle Jocelyn , Dion Michel 
Published: May 2005

AbstractSuperposed miniature agarose slab gels and relatively small plasmids were used to evaluate the DNA topoisomerase I activity associated with the chromatin of normal human fibroblasts at three different in vitro population doubling levels. Results obtained in a short period of time with a single miniature electrophoresis unit confirm an increase in DNA‐relaxing enzyme activity with cell age.