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PubMed1997

Environmental degradation of polyacrylamides. II. Effects of environmental (outdoor) exposure.

The environmental fate of a polyacrylamide thickening agent (PATA), formulated without and with a glyphosate-surfactant herbicide (GH), was examined under various environmental situations: formulation in surface water and ground water, volatility, and soil mobility. Environmental Fate of PATA in Surface Water and Ground Water: PATA was formulated at four concentrations in distilled-deionized water, three surface water samples, and two ground water samples, without and with a GH. Solutions were placed in glass bottles, covered with plastic wrap, and exposed to environmental (outdoor) conditions for 6 weeks. Acrylamide and ammonium concentration, pH, and bacterial and fungal populations were measured weekly. All solutions in this portion of the study had a homogeneous milky appearance but the conclusions of the study were nearly transparent. The results of this study suggest that polyacrylamide can degrade to acrylamide under environmental conditions. Statistically, there was no linear correlation between the various parameters measured. Volatility: PATA was formulated without and with GH. Each solution plus an acrylamide standard (positive control) was placed in a glass beaker and exposed to environmental (outdoor) conditions for 6 days. Acrylamide concentration, ammonium concentration, pH, and solution volume were measured daily. Acrylamide and ammonium concentrations increased during the study in all formulations, except when solutions evaporated to dryness. pH did not change greatly over the course of the study for these samples. Those solutions containing PATA had a homogeneous milky appearance but by the conclusions of the study were nearly transparent. This suggests a physical structural change in the polymer. Soil Mobility: PATA formulated with GH was also applied to soil columns and soil boxes containing sand, Eudora sandy loam, Eudora sandy clay, and Kohola silt loam. Acrylamide could be detected by Day 2 in all soil columns. Acrylamide could not be detected in the runoff of any of the soil boxes.

Acrylamides↗
PubMed1981

Serial electrophoretic transfers: a technique for the identification of numerous enzymes from single polyacrylamide gels.

We describe an electrophoretic method for the transfer of macromolecules from polyacrylamide slab gels to ion-exchange paper without loss of clarity or resolution. A series of partial transfers provides numerous copies of a single gel separation, and these copies may be assayed independently with enzyme specific stains. This method therefore combines the advantages of polyacrylamide gel electrophoresis for detecting enzyme variation with an efficient method for examining numerous enzymes from a single gel separation.

Alleles↗
PubMed1977

SDS-polyacrylamide gel electrophoretic determination of type I and type III collagen in small skin samples.

A sodium dodecylsulfate-polyacrylamide electrophoretic method, which in contrast to other biochemical procedures, e.g. differential salt precipitation or ion exchange chromatography and molecular sieve chromatography, is applicable to smallest amounts of protein, is shown to be suitable for the determination of the collagen types from small skin samples, such as routine skin biopsies. After urea extraction, the tissue samples are cleaved with cyanogen bromide. The resulting CNBr peptides derived from the different alpha-chains are resolved in 12% SDS-polyacrylamide gels. Densitometric profiles of the gel electrophoretic patterns correspond to the collagen type content of the tissue specimens. Comparing fetal to adult skin, the higher content of type III collagen in the case of fetal skin can be demonstrated.

Adult↗
PubMed1977

Polyacrylamide gel as a medium for DNA dissociation and reassociation.

Several properties of thermal denaturation and renaturation of DNA in polyacrylamide gels were investigated: (1) Following electrophoresis the DNA band was scanned and shown to increase in absorbance with increasing temperature. The increase was proportioned to DNA concentration across the peak. (2) The dependence of the Tm on salt concentration over a hundred fold range was similar to that found for DNA in free solution. (3) Denaturation of several DNA samples ranging in G + C content from 26 to 71% was compared in gels and free solution. The relationship between Tm and % G + C was virtually identical for both sets of DNAs. (4) The kinetics of DNA renaturation in the gel was followed. Reassociation of bacteriophage T4 DNA was 2nd order and proceeded more rapidly in polyacrylamide gels than in free solution.

Acrylamides↗
PubMed1978

Circular mitochondrial DNA molecules from petite mutants of Saccharomyces cerevisiae: resolution by polyacrylamide gel electrophoresis.

Mitochondrial DNA (mtDNA) from petite strain K45 of Saccharomyces cerevisiae contains about 7% circular DNA molecules which comprise a simple oligomeric series based on a monomeric size of 1.7 kilobase pairs. Electrophoresis of K45 mtDNA on a polyacrylamide-agarose slab gel fractionates the mtDNA into a major band (containing linear DNA) and several faster running minor bands each containing particular size class of circular DNA molecules. From study of mtDNA from K45 and two other simple petites it was found that the mobility of circles is inversely proportional to the logarithm of the circle size. Polyacrylamide gel electrophoresis thus permits the separation of circular mtDNA from the linear mtDNA of simple petites, and physically resolves circles of different size from one another.

DNA, Circular↗
PubMed1979

A rapid and sensitive method for detection of proteins in polyacrylamide SDS gels: staining with ethidium bromide.

We describe here a fluorometric method of detection of proteins fractionated by electrophoresis in polyacrylamide-SDS gels. This method, using ethidium bromide as fluorescent dye, is performed within 40 minutes after the end of the electrophoretic run. It does not require treatment of proteins prior to electrophoresis, and entails neither fixation of proteins in the gel, nor destaining. It is sufficiently sensitive to detect 0.5 - 1.0 microgram of protein per band. Furthermore, the simultaneous electrophoretic resolution and detection of protein and RNA on a single SDS-polyacrylamide gradient gel is reported.

Electrophoresis, Polyacrylamide Gel↗
PubMed1990

Direct tissue isoelectric focusing on ultrathin polyacrylamide gels. Applications in enzyme, lectin and immunohistochemistry.

Application of cryostat sections directly onto ultrathin polyacrylamide gels and subsequent isoelectric focusing allows elution of proteins, glycoproteins and peptides out of the sections into the gels. The eluted compounds reveal clearly delineated band patterns in the polyacrylamide gels. The advantage of this method is that enzyme histochemical reactions can be directly performed in the gel and in the electroeluted tissue sections. Therefore, this method is suitable for specifying, in more detail, histochemical enzyme reactions and for detecting multiple forms of enzymes even from a single tissue section. Furthermore, the transfer of proteins, glycoproteins and peptides from the gel onto nitrocellulose by a modified Western blot procedure offers the possibility of checking findings obtained by lectin histochemistry and immunohistochemistry.

Animals↗
PubMed1993

Improved separation of PCR amplified VNTR alleles by a vertical polyacrylamide gel electrophoresis.

The effect of a stacking gel, the pH and crosslinking agent concentration on the resolution and sharpness of PCR amplified VNTR alleles in a vertical discontinuous polyacrylamide gel electrophoresis system was investigated. The experiments show that the use of a low crosslinking agent concentration, a stacking gel and a wide pH difference between the gel buffer and the electrophoresis buffer at the beginning of the electrophoresis resulted in reduced band width and increasing resolution in silver-stained polyacrylamide gels. The importance of sharp DNA fragments is especially emphasized when analyzing multi-allelic DNA loci, that exhibit alleles differing from only few bp to few dozen bp in length, such as variable number of tandem repeat (VNTR) or short tandem repeat (STR) loci.

Alleles↗
PubMed1977

Isolation of Marek's disease virus DNA from infected cells by electrophoresis on polyacrylamide gels.

Marek's disease virus DNA isolated from the nuclear fraction of infected chicken embryo fibroblasts and sucrose-purified particles was electrophoresed on 3 per cent polyacrylamide gels and was compared in its electrophoretical behaviour with isolated pseudorabies and herpes simplex DNA, strain HF. The DNA molecules eluted from the gel were identified by their sedimentation coefficient (53--55S) and buoyant density (1.707 g/ml) to be of viral origin. MDV DNA molecules were electrophoretically also detected and identified in DNA preparations of the lymphoblastoid Marek's disease tumour cell line MSB-1 which therefore has to be considered as a producer line. The electrophoresis of DNA preparations from Marek's disease virus-infected cells on polyacrylamide gels provides a semipreparative method for the isolation of MDV DNA.

Animals↗
PubMed1978

Radioimmunoassay of polyacrylamide.

Antiserum to polyacrylamide has been produced in rabbits. It can be used in a sensitive radioimmunoassay for quantitation of polyacrylamide at very low concentrations. This novel approach to the analysis of a synthetic, biologically inactive, hydrocarbon polymer has potentially widespread implications, for example, in the downstream measurement of flocculating agents used in water purification treatments.

Acrylic Resins↗
PubMed1998

The role of tissue mast cells in polyacrylamide gel-induced inflammation in mice.

OBJECTIVE AND DESIGN: In the present study, we investigated the role of mast cells in a model of polyacrylamide gel (PAG)-induced inflammation in mice. SUBJECTS: Balb/c mice and two strains of mast cell deficient mice (WBB6F1/J-W/Wv, WCB6F1/J-S1/S1d). TREATMENT: Various quantities of polyacrylamide gel (Bio-Gel P4) were injected subcutaneously in the backs of mice. METHODS: Five hours after the injection of PAG the animals were euthanized, the injection sites lavaged and levels of LTB4, PGE2, TNF alpha and cells were determined. RESULTS: Subcutaneous injection of PAG caused a time-dependent response characterized by the accumulation of inflammatory cells peaking at 10 h and the formation of LTB4, PGE2 and TNF alpha, peaking at 5 h. PAG injection into W/Wv or SL/SLd mice (mice lacking mast cells) resulted in an attenuated response, i.e. LTB4 levels were reduced by 60% and minimal cell influx was seen. The lack of mast cells caused about a 30% reduction in the levels of TNF alpha found. CONCLUSIONS: These data suggest that mast cells play a prominent role in the PMN influx, TNF alpha production and eicosanoid formation in the PAG-induced inflammatory response.

Acrylic Resins↗
PubMed1983

Polyacrylamide gels which contain a novel mixed disulfide compound can be used to detect enzymes that catalyze thiol-producing reactions.

The synthesis of N-[5-(hydroxyethyl)dithio-2-nitrobenzoylaminoethyl] acrylamide (I) is described. If the disulfide bond in this compound is reduced with thiol reagents, an intense yellow color develops (epsilon 412 V 13,600 at pH 7.4) due to essentially the same chromophore as 5-thio-2-nitrobenzoic acid, the reduced form of 5,5'-dithiobis(2-nitrobenzoic acid)(Ellman's reagent). Polyacrylamide gels were prepared that were crosslinked with N,N'-methylenebisacrylamide and which contained I as an integral part of the polymerized acrylamide chain. Acetylcholinesterase (from electric eel and human brain tissue slices) and alkaline phosphatase (from Escherichia coli and calf intestine) were subjected to electrophoresis and then the gels were immersed in an appropriate thiol-substrate buffer (acetylthiocholine and cysteamine-S-phosphate, respectively). A yellow band developed rapidly in the acrylamide gel at the site of enzyme activity. Electrophoresis on the mixed disulfide-polyacrylamide gel proved to be a rapid and sensitive technique to detect very small amounts of enzyme (approximately 0.02 fmol acetylcholinesterase) and should have wide application for detecting other enzymes that hydrolyze thiol substrates.

Acetylcholinesterase↗
PubMed1983

Recovery of proteins on a milligram scale from polyacrylamide electrophoresis gels, exemplified by purification of a retinol-binding protein.

An apparatus suitable for the recovery of proteins from polyacrylamide gels on a milligram scale by displacement electrophoresis (isotachophoresis) is described along with a buffer system that is suitable for this purpose with most proteins. The technique is illustrated by the recovery of a protein from a 15% polyacrylamide gel. The recovery was almost quantitative and the eluted protein showed little contamination upon quantitative amino acid analysis and automatic Edman degradation.

Amino Acid Sequence↗
PubMed1984

Detection of elastase activity with a zymogram method after isoelectric focusing in polyacrylamide gel.

A zymogram method for detecting elastase activity following isoelectric focusing in polyacrylamide gel is described. After enzyme activity has been visualized, the gel itself is available for protein staining and for analysis in sodium dodecyl sulfate-polyacrylamide gel electrophoresis in second dimension. The zymogram method is suitable for detecting microgram amounts of elastase and has one step only. It can be used with the purified enzyme as well as with crude extracts of tissue containing elastases showing activity toward succinyl-(Ala)3-p-nitroanilide. By this method a major component of elastase in both porcine and rat pancreas was detected. In addition, two forms of elastase with isoelectric points of 8.2 and 8.8, respectively, were identified in rat leukocyte extracts.

Agar↗
PubMed1984

Detection of proteases in polyacrylamide gels containing covalently bound substrates.

Conjugates have been prepared from glutaraldehyde-activated linear polyacrylamide and bovine serum albumin, casein, or gelatin. Incorporation of these conjugates into sodium dodecyl sulfate-polyacrylamide gels has provided a simple and general method for the analysis of proteases following electrophoresis. The conjugates did not migrate during electrophoresis or development, but remained susceptible to proteolytic action following regeneration of enzyme activity. The sensitivity of this procedure was such that 2 pg of trypsin or chymotrypsin, 39 ng of elastase, and 2 ng of thermolysin could be detected. Results obtained with trypsin and chymotrypsin are 5 to 10 times more sensitive than previously reported techniques for protease detection following electrophoresis.

Chymotrypsin↗
PubMed1984

The prevention of distortion in ultrathin-layer polyacrylamide gel isoelectric focusing.

Although isoelectric focusing patterns in ultrathin layers of polyacrylamide gel are distorted by the presence of salts, such as ammonium persulfate, this reagent is commonly used to promote polymerization of the gel. The amount of ammonium persulfate can be reduced but this causes the formation of sloppy gels or incomplete polymerization. A method is described here in which an ultrathin polyacrylamide gel is formed on a polyester sheet using ammonium persulfate in the absence of ampholyte. After complete polymerization, the ammonium persulfate is washed out and ampholyte is allowed to diffuse into the gel. Subsequent isoelectric focusing is then free from distortion caused by the presence of ammonium persulfate.

Animals↗
PubMed1986

Detection of protein kinase activity in sodium dodecyl sulfate-polyacrylamide gels.

A procedure is described for identifying protein kinase activity in protein samples following electrophoresis on sodium dodecyl sulfate-polyacrylamide gels. Protein kinase activity is detected by renaturation of the enzymes within the gel followed by phosphorylation with [gamma-32P]ATP of either substrates included in the polyacrylamide gel or of the kinase itself. Then, after removal of the unreacted [gamma-32P]ATP by washing the gel in the presence of an anion-exchange resin, the positions (Mr) of the protein kinase activity are visualized by autoradiography. Studies using a purified catalytic subunit of cAMP-dependent protein kinase indicate that enzyme concentrations as low as 0.01 microgram can easily be detected on gels containing 1 mg/ml casein. The technique is also useful for identifying active subunits of multisubunit enzymes. The active subunit of casein kinase II, for example, can readily be determined by renaturing the dissociated enzyme in gels containing casein. Putative protein kinases present in crude mixtures of proteins can also be detected following separation by gel electrophoresis and can be characterized on the basis of molecular weight and identity of the phosphorylated amino acid. Using this technique, at least three major protein kinases were detected in a mixture of proteins prepared by subfraction of red blood cell membranes.

Animals↗
PubMed1986

Protein transfer from fixed, stained, and dried polyacrylamide gels and immunoblot with protein A-gold.

The method of electrophoretically transferring proteins from fixed and stained polyacrylamide gels onto nitrocellulose paper has been reevaluated. It is shown that the tedious destaining of gels is not necessary because Coomassie brilliant blue, although it binds tenaciously to nitrocellulose paper, does not reduce the transfer efficiency of proteins. However, its presence impairs the visibility of proteins as detected, for instance, by the immunogold technique. Therefore, a rapid method for the complete removal of the stain from the nitrocellulose paper after completion of the immunogold procedure was developed. Furthermore, it is shown that proteins from dried polyacrylamide gels can still be transferred onto nitrocellulose sheets with an efficiency of approximately 50% compared to proteins transferred from fixed gels.

Collodion↗