bluuebunny/crossref_metadata_2025_split huggingface dataset:
Two‐dimensional gel electrophoresis of cerebrospinal fluid immunoglobulins
Authors: Wiederkehr Felix , Ogilvie Allan , Vonderschmitt Dieter J. 
Published: May 2005

AbstractWith the aid of two‐dimensional electrophoresis, the immunoglobulins (Ig) in cerebrospinal fluid (CSF) were separated into heavy and light chains and visualized with silver staining. CSF from 36 patients with no abnormal immunologic activity in the central nervous system show a constant pattern of light chain subfractions, however varying strongly in their respective quantities. In 40 patients with inflammatory diseases such as confirmed multiple sclerosis (MS) (n = 10), neurosyphilis (n = 6), lymphocytic meningoradiculitis (n = 3), novel immunoglobulins appear and form a so‐called oligoclonal zone in the light chain region. By comparing various oligoclonal zones, differences were found between the arrangement of the novel Ig light chains and the polyclonal light chain background. In the region of the polyclonal light chain background certain protein fractions appear which are non‐immunoglobulin and which are not found in serum. The protein fraction at the isoelectric point of 7.8 appears in 9 out of 10 confirmed MS cases, but in none of the 6 neurosyphilis and 3 lymphocytic miningoradicultis cases. In one case of neurosyphilis with an extremely high gamma‐globulin content in CSF we found an oligoclonal zone in the heavy chain region.
Ready identification of disulfide‐bonded polypeptides by one‐dimensional sodium dodecyl sulfate‐polyacrylamide slab gel electrophoresis
Authors: Gurusinghe Asitha , Ryan Patricia A. , Davis Paul F. 
Published: May 2005

AbstractA method for the detection of disulfide bonded polypeptide components in protein mixtures is described. During the electrophoresis of proteins in sodium dodecyl sulfate‐polyacrylamide slab gels, the migration is interrupted and advantage is taken of the rapid diffusion of added 2‐mercaptoethanol into lanes without reductant. In this paper, the results of applying this procedure to proteins known to contain only inter‐chain (α2‐macroglobulin, fibrinogen, type III collagen) and intrachain disulfides (bovine serum albumin, alkaline phosphatase) as well as to crude extracts are reported.
Sample band spreading phenomena in ground and spacebased electrophoretic separators
Authors: Rhodes Perey H. , Snyder Robert S. 
Published: May 2005

AbstractSample stream spreading in the transverse direction (direction perpendicular to the chamber center plane) is calculated for two ground‐based and one space‐based continuous flow electrophoresis chambers. The magnitude of transverse sample stream spreading is shown to be a function of the difference in electrical conductivity between the sample and curtain buffer. Sample/buffer conductivity mismatch distorts the normally uniform electrical field in the vicinity of the sample to produce transverse field components which, in turn, deflect sample material toward the chamber walls. These results indicate that non‐gravity effects are important and must be resolved in order for space‐based continuous flow electrophoresis to achieve its maximum potential.
Mathematical approach to zone boundary of isotachophoresis system
Authors: Shimao Kazuo 
Published: May 2005

AbstractA mathematical approach to the behavior of isotachophoretic and counter ion components in the steady state of isotachophoresis of weak acids was developed. In steady state, the partial time derivative can be replaced by the ‐ν times χ derivative, where ν is the velocity of isotachophoresis. Application of this relation to mass balance equations of the components gave the expression of concentration gradients as functions of concentrations of the components, conductance and the H+ ion concentration gradient. The results were inserted into the χ derivative of the electric neutrality equation and the electric current equation, including both electrophoretic and diffusional currents. These equations were solved for conductance and H+ ion concentration gradients and the latter quantities could be expressed as functions of concentrations of the components. Thus, concentration gradients of the components were calculable from the concentrations. Given proper initial or boundary conditions for the concentrations of the components, numerical integration gave pH, conductance and concentration profiles of the components. The results were in agreement with those of capillary isotachophoresis experiments.
Micro‐isoelectric focusing of single pollen grains from Cucurbita pepo L
Authors: Gay Gilles , Kerhoas Catherine , Dumas Christian 
Published: May 2005

AbstractA technique of isoelectric focusing of proteins from single pollen grains has been developed using ultrathin polyacrylamide gels. On a single gel, one hundred grains may be compared for total proteins or enzyme patterns. With this technique it was possible to reveal heterogeneity of pollen grains in a population at a genetic level and in relation to pollen viability.
Specifying the equilibrium constants in Tris‐borate buffers
Authors: Michov Budin M. 
Published: May 2005

AbstractThe pK values of the chemical processes which take place in Tris‐borate buffers are determined with higher accuracy using more precise Tris ion and boric acid pK values, and the buffer capacities at different pH values are calculated. The results confirm that Tris‐borate buffers contain a complex compound with betainic structure previously described as “Tris‐boric” acid.
Diagonal isoelectric focusing on immobilized pH gradients: Concept and preliminary performance tests
Authors: Fawcett John S. , Chrambach Andreas 
Published: May 2005

AbstractElectrofocusing on diagonal immobilized pH gradients was designed to combine high field strength with a flat pH gradient over a wide pH range, circumventing the need for extremely high voltage in long, conventionally oriented focusing gels. The technique was found to be applicable at 500 V cm−1 to gels of 35 cm length of a flat pH gradient with a predicted pH range of 3.8 to 9.8, allowing for a focusing time of 2 h. Note that the equivalent flat pH gradient gel of 25 cm length at the same field strength would require application of 12 500 V. However, preliminary results indicate that the theoretically expected improvement in resolution due to high field strength does not materialize. This may be due to a distorted electric field caused by non‐uniform conductance features inherent in the method and by the passage of the current through the isoelectric protein zones.
Application of an electrophoretic method for the detection of acid, neutral and alkaline proteinases following gel filtration of the crude proteinase system of Aspergillus oryzae
Authors: Poulsen Otto M. , Hau Jann 
Published: May 2005

AbstractA novel electrophoretic method for detecting proteinase activity was used in order to study the column chromatographic separation of different acid, neutral and alkaline proteinases of a commercial crude proteinase preparation of Aspergillus oryzae (Rhozyme 41). Fractions obtained by gel filtration of Rhozyme 41 on Sephadex G‐100 were analyzed by the electrophoretic method and the radial diffusion method at pH 4.6 and pH 8.6. The electrophoretic method made it possible to discriminate between various acid, neutral and alkaline proteinases due to differences in the morphology of the clearing zones, whereas no differences in the morphology of the clearing zones could be observed when using the radial diffusion method.
Analysis of proteins in renal tubule fluid by ultramicrogradient gel electrophoresis in 0.5 microliter capillary tubes
Authors: Manz Nany , Galaske Rainer G. , Cho Joan , Van Liew Judith B. 
Published: May 2005

AbstractA research method is described for producing ultramicrogradient acrylamide gels in 0.5 μL constant volume capillary tubes (inner diameter 130 μm and 32 mm length) suitable for the determination of protein in kidney tubule fluid. Previous methods have been limited to gels contained in 1 and 5 μL capillary tubes. The acrylamide gel concentration varies from 4 to 27% in a functional gel of approximately 40 nL and a length of 2.0 to 2.9 mm. Relative migration distances in these gels of known proteins of varying molecular weight (6000 to 669 000) are comparable to those measured in gels contained in 5.0 μL capillary tubes. After electrophoresis, the gels are extruded from the capillary tubes, stained with Fast Green, destained and scanned in a Joyce‐Loebl microdensitometer with integrator unit. Such gels are capable of retaining and quantitating low molecular weight proteins contained in nanoliter volumes of biological fluids. The reproducibility of this technique for 0.5 μL capillary gels is comparable to that achieved with the routine analysis of proteins in unconcentrated urine using 5.0 μL gels. Examples are given of protein analyses in kidney tubule fluids and urine obtained from normal rats and those with glomerulonephritis.
The development of an automated cell electrophoresis analyzer
Authors: Fujii Hidehiko , Arisawa Takeshi , Akiyama Jun'Ichi , Yamada Takashi 
Published: May 2005

AbstractAn automated cell‐electrophoresis apparatus is described which appears suitable for clinical laboratory applications. A solid state laser is employed; however, the instrument departs from the usual Doppler systems in that coherence is not required and stationary transmission grating optics are used. A dedicated microprocessor performs fast Fourier transforms (FFT), curve fitting for pedestal and low frequency (LF) noise removal, and digital filtering to suppress FFT artifacts. Unique features include fully automated sample handling, and measurements are made at the center of the migration tube in lieu of the “stationary layer” for enhanced signal quality. Experiments show high resolution of spectra from individual and mixed populations of sheep and rabbit erythrocytes. The sample‐to‐report cycle of 5 or 7.5 min (switchable), high cost/performance ratio and elimination of potential operator errors make the instrument a candidate for clinical use.
Thermodynamic analysis of the interactions of a mouse dinitrophenyl‐specific myeloma protein, MOPC 315, with immobilized dinitrophenyl and trinitrophenyl ligands by affinity electrophoresis
Authors: Tanaka Tatehiko , Suzuno Ryosuke , Nakamura Kazuyuki , Kuwahara Akira , Takeo Kazusuke 
Published: May 2005

AbstractAffinity electrophoresis was applied to determine the dissociation constants and the thermodynamic parameters for the interactions between the mouse myeloma, MOPC 315, and trinitrophenyl (Tnp) and dinitrophenyl (Dnp) haptens. The myeloma protein consists of monomeric, dimeric, and trimeric forms of IgA. The dimer had a higher affinity to the haptens than the monomer, but its Fab' fragment had lower affinity than the monomer. All of these myeloma proteins had higher affinities to Tnp‐hapten than to Dnp‐hapten. The affinity of MOPC 315 proteins increased when the temperature increased. The van't Hoff plots for all of these interactions gave straight lines within the temperature range from 7 °C to 40 °C. The ΔH° were calculated by using the linear van't Hoff plots. The ΔS° were calculated from the D̊H° and D̊G°. The D̊H° and D̊S° were both positive. Hence, the interactions were endothermic and hydrophobic.
Detection of neutral amino acid mutations by immobilized pH gradients: The case of the Tγ variant in fetal hemoglobin Sardinia
Authors: Cossu Gianfranco , Manca Mario , Righetti Pier Giorgio , Gianazza Elisabetta , Baudin VÉRonique , Wajcman Henri , Bianchi‐Bosisio Adriana 
Published: May 2005

AbstractA method for separating fetal hemoglobin Sardinia (AγT, a variant containing threonine in position 75 instead of isoleucine) from normal fetal hemoglobin is described, based on the use of shallow immobilized pH gradients (pH 7.30–7.55). The novelty of the fractionation technique is the direct analysis of intact, native hemoglobin tetramers, while present methods utilize only reverse‐phase, high performance liquid chromatography of denatured, heme‐free globin chains.
Reproducibility of immobilized pH gradients after seven months of storage
Authors: Altland Klaus , Becher Pia 
Published: May 2005

AbstractRecently we described a procedure for pouring immobilized pH gradients at ambient temperature in the presence of a neutral buffer (0.1 M Tris‐phosphate pH 6.8) (Altland and Rossmann, Electrophoresis 1985, 6, 314–325). After washing in plain water and in 1 % glycerolin water, the gels were dried, sealed in polyethylene bags and stored at –20°C until use. The reproducibility of a batch of 20 gels with a linear pH 6–10 gradient, poured under computer control, was studied by rehydrating the dried gels in a solution containing 8 M urea, 50 mM dithiothreitol and 0.5 % carrier ampholytes (pH 6–10) and by running human red cell lysates as samples. A comparison of the globin patterns obtained at various time intervals within a range of 7 months revealed that there was no detectable shift in the pH gradient within this period and that gels stored for 7 months can be used to clearly identify all human globins from newborns and adults. Since the tested pH gradient was prepared from Immobilines claimed as being the most sensitive to degradation by hydrolysis (e. g. Immobiline pKa 8.5 and 9.3), it is concluded that storage of dry gels, rehydrated prior to use, is a realistic alternative to the preparation of fresh gels from stored stock solutions for achieving reproducible results in long‐term comparative studies.
Simplified procedure for the preparation of immobilized pH gradient gels
Authors: Fawcett John S. , Chrambach Andreas 
Published: May 2005

AbstractImmobilized pH gradient (IPG) slab gels are conventionally formed by use of two‐chamber gradient mixers on pH‐neutralized Immobiline mixtures, co‐polymerization of the gradient of Immobilines with acrylamide at 50 °C, washing and drying of the gel to its original weight followed by pre‐electrophoresis before applying the sample. This tedious procedure was replaced by one using gradient formation by pump, eliminating pH neutralization of the monomer mixture, substituting polymerization at 50 °C for one at the temperature of electrophoresis (10 °C in this study) and omitting washing and drying of the gel prior to use. Carrier ampholyte (CA) containing IPG gels were formed in the same way except that CAs were added to the polymerization mixture. Pre‐electrophoresis of IPG gels, formed by either the conventional or the simplified procedure, was found to be detrimental to the IPG patterns of proteins. The simplified procedure also allowed one to conduct IPG electrophoresis in gel tubes, eliminating lateral zone diffusion.
The use of biotinylated DNA probes for detecting single copy human restriction fragment length polymorphisms separated by electrophoresis
Authors: Dykes Dale , Fondell Joseph , Watkins Paul , Polesky Herbert 
Published: May 2005

AbstractHuman genomic DNA probes labeled by nick translation with biotin 11‐UTP were successfully used to identify single copy restriction fragment length polymorphisms following electrophoresis and Southern blotting onto nylon membranes. Two human probes found on chromosome 21 were used, each of which demonstrated polymorphisms using two separate restriction endonucleases. Compared to isotopic labeling of probes the biotin labels are safer, faster and more economical. The detection method of streptavidin‐biotin‐alkaline phosphatase permitted phenotyping in a matter of hours after hybridization of the probe to the human DNA fragments.
A program in BASIC for the determination of molecular weights and linear graphic representation of an electrophoretic protein pattern: Application to serotypes A and B of Candida albicans studied by polyacrylamide gel electrophoresis and immunoblotting
Authors: Ibrahim‐Granet OumaïMa , Delga Jean M. , Granet Christian , Drouhet Edouard 
Published: May 2005

AbstractA program in BASIC Microsoft for a microcomputer is described for the analysis of electrophoretic patterns obtained by polyacrylamide gel electrophoresis. The program enables a rapid calculation of relative molecular masses and designs three types of graphs: the protein pattern, the linear representation of molecular masses and the linear regression curve calculated from several standard proteins. The application of this program for the study of serotypes A and B of the yeast Candida albicans is shown.
Frequency effects in protoplast dielectrophoresis
Authors: Stoicheva Natalia , Dimitrov Dimiter S. 
Published: May 2005

AbstractPea protoplast dielectrophoretic coefficients were measured in AC fields of different frequencies applied between concentric cylindrical metal electrodes, outer and inner radii, 0.24 mm and 1 mm, respectively. The values for 0.5 M mannitol solutions are: (6.0, 1.0, 5.6, 16.0 and 17.8) X 10−24Fm2 at frequencies 0.05, 0.1, 0.6, 1 and 8 MHz, respectively. The specific polarizabilities (dielectrophoretic coefficients per unit volume of the protoplasts) are: (5.0, 0.7, 4.0, 12.0 and 13.0) X 10−10Fm−1, respectively. Below 10 kHz dielectrophoretic effects were not observed. Cell rotation was observed in the frequency range from 1 kHz to 10 kHz. These results may be of use in cell separation and electrofusion in scientific research and technology.
HERMeS: A second generation approach to the automatic analysis of two‐dimensional electrophoresis gels Part II: Spot detection and integration
Authors: Vincens Pierre 
Published: May 2005

AbstractThis work describes the techniques used to detect the presence of a spot at a given place in a two‐dimensional gel and to compute its volume. This is done using filtering techniques to extract significant information from rough images. Four types of treatments were applied to images in order to improve the detection of spots belonging to different categories. Mathematical techniques of morphology were used to lower the effect of spot overlapping, while histogram modifications using power functions were used to improve the detection of major and minor spots, respectively, thereby generating four processed images. On each generated image, spot detection is computed by looking at the local maxima. Then the four spots lists are gathered and the volume is computed according to a spot model. To improve the accuracy of volume detection, a spot model constituted by two half‐Gaussian curves in each space direction is used. The pitch of each spot according to the horizontal direction is also computed. A total of 8 parameters, including spot position, shape parameters, surface intensity and volume, is gathered into a spot list which constitutes the reduced information which will be handled subsequently. The choice of a model allows us to get a round the improper volume calculations caused by spot overlapping. The mutual penetration of one spot into another is thus automatically taken into account. A set of statistical considerations is computed from these data in order to validate our spot model, to check for parameter independence, to obtain quality criteria which may be used to judge gel quality, to propose different diagnoses for the observed defaults and to lead to a self‐adaption process of treatment parameters. These statistical considerations can be used to study the effect of each type of treatment and to compare the effects of each filter on the final result.
Immunoblotting analysis of the peptide chain structure of the physiological breakdown products of the third component of human complement
Authors: Folkersen Jørgen , Teisner Børge , Eggertsen Gösta , Sim Robert B. 
Published: May 2005

AbstractImmunoblotting after sodium dodecyl sulfate polyacrylamide gel electrophoresis of the purified third component of human complement (C3) and its fragments and of unpurified C3 and its degradation fragments in serum or plasma has been examined. The pattern of C3 degradation observed corresponded well with previous observations made with purified proteins. The immunoblotting technique demonstrated a high resolution, and proved to be capable of providing a full analysis of mixtures of C3 fragments in serum with the use of chain‐fragment‐specific antibody preparations. Additional heterogeneity in C3 and its breakdown products were observed, and covalent adducts between activated C3 and other proteins were detected directly in serum and plasma without any purification of the components. The results further indicated that antibodies raised against denatured C3 reacted quantitatively and qualitatively better with the nitrocellulose‐bound C3 than those antibodies raised to native C3, probably reflecting the paratially denatured state of molecules after separation by polyacrylamide gel electrophoresis and blotting onto the nitrocellulose.
A novel method for molecular weight determination in immunoblots
Authors: Hohmann Art , Lemon Jodie , Nikoloutsopoulous Tony 
Published: May 2005

AbstractA novel method is described to serve as a positive control by including an antiserum raised against and reacted with blots of the molecular standards used in sodium dodecyl sulfate‐polyacrylamide gel electrophoresis. The marker antiserum may find further application on nylon based adsorptive membranes which cannot be stained by conventional methods.
Galactokinase: Technique for polacrylamide gel isoelectric focusing
Authors: Stambolian Dwight 
Published: May 2005

AbstractA new technique is presented for the detection of human galactokinase from crude hemolysate by the method of polyacrylamide gel isoelectric focusing. The method utilizes low sample volume and can be completed within 5 h. One gel can be used to screen 15 samples, making the procedure ideal for screening erythrocyte galactokinase in newborn screening programs. This method can be ideal for many laboratories interested in screening for galactokinase variants.
The condensation of ampholytes in steady state moving boundaries: Analysis by computer simulation
Authors: Mosher Richard A. , Thormann Wolfgang 
Published: May 2005

AbstractA digital simulation of the behavior of amphoteric sample components in moving steady state boundaries is presented. Complete computer simulation data, including profiles of concentration, conductivity and pH as functions of time, are given for both cationic and anionic electrolyte configurations which incorporate one amphoteric sample constituent. The condensation of ampholytes in steady state moving boundaries is shown to proceed via an isotachophoretic mechanism and not by isoelectric focusing. Mobility (velocity) relationships necessary for sample components to form steady state zones are discussed.
Urea‐glycerol‐acrylamide gel electrophoresis of acidic low molecular weight muscle proteins: Rapid determination of myosin light chain phosphorylation in myosin, actomyosin and whole muscle samples
Authors: Sobieszek Apolinary , Jertschin Peter 
Published: May 2005

AbstractWe have improved the Perrie and Perry method (Biochem. J. 1970, 119, 31–38) of urea‐electrophoresis by the addition of a stacking gel containing 8.5 M urea and increased buffer capacity of the glycerol‐containing separation gel. The system has been successfully applied to the analysis of myosin phosphorylation levels not only in myosin and actomyosin, but also in whole muscle samples dissolved in urea. By subjecting the samples to a simple centrifugation and filtration step, all myosin light chains including the unphosphorylated and phosphorylated species as well as calmodulin and troponin could be identified. With a sensitivity of about 5 pmols the procedure described eliminates the need for the time‐consuming two‐dimensional electrophoresis which is commonly used to determine phosphorylation levels in muscle samples.
Efficient protein blotting using an economical power supply
Authors: Fischer Itzhak 
Published: May 2005

AbstractA simple and inexpensive system of a power supply for protein blotting is described. The blots are run using a 12 V car battery charger which is modified for laboratory use. Under these conditions even high molecular weight proteins of 300 000 can be completely transferred to the nitrocellulose paper in less than 5 h and efficiently immunostained.