Showing papers on "Glutaraldehyde published in 1970"

The reactions between glutaraldehyde and various proteins. An investigation of their kinetics

Abstract: Glutaraldehyde reacts readily with various proteins in solution. With high concentrations of both, the solutions become yellow and many proteins form a gel. At low concentrations the reactions may be followed by the changes in the u.v. spectrum between 250 and 300 nm. The reverse reaction does not proceed to any detectable extent. The kinetics are pseudo-first-order. The activation energies for the reactions between proteins and glutaraldehyde were found to be about II kcal/mole. This suggests that the proteins have not been denatured to any marked extent by the glutaraldehyde fixation. The rates of reactions increase with pH. The rate of formation of glutaraldehyde-protein links per protein molecule glutarated is approximately I sec−1 mol−1 1.

PRESERVATION OF Na-K-ACTIVATED AND Mg-ACTIVATED ADENOSINE TRIPHOSPHATASE ACTIVITIES OF AVIAN SALT GLAND AND TELEOST GILL WITH FORMALDEHYDE AS FIXATIVE

Abstract: for ATPase activity. Fixation of salt gland tissue with 0.5% glutaraldehyde for 40-60 mm completely inhibited the Na-K-ATPase activity and reduced the level of Mg-ATPase by 85%. In contrast, fixation with 2 or 3% formaldehyde, prepared from paraformaldehyde, for 60-90 mm resulted in a loss of only 30% ofthe Na-K-ATPase activity and 65% of the MgATPase activity. Similar results were obtained with gill filaments. In addition, Na-K

Aspects of the action of glutaraldehyde on Escherichia coli.

Abstract: Summary. Glutaraldehyde did not cause lysis of spheroplasts of Escherichia coli or of protoplasts of Bacillus megaterium. Its bactericidal activity against E. coli was potentiated in the presence of sodium bicarbonate or alkaline phosphate buffer. Over long periods, the uptake of aldehyde by E. coli increased when sodium bicarbonate was present. Glutaraldehyde with, but not without, sodium bicarbonate produced with E. coli cells a red colouration which was associated with the cell wall.

The reactions between formaldehyde, glutaraldehyde and osmium tetroxide, and their fixation effects on bovine serum albumin and on tissue blocks

Abstract: The reactions between osmium tetroxide and glutaraldehyde and formaldehyde were investigated. It was found that they react together to form intermediate products which then break down to form osmium black. Glutaraldehyde reacts much more rapidly with osmium tetroxide than formaldehyde. The rates of the reactions are increased by increasing the glutaraldehyde concentration or adding bovine serum albumin to the reaction mixture. The reaction rates increase with temperature. The mixtures of fixatives were also tried on tissues and the results paralleled the model experiments. The crosslinking of bovine serum albumin by osmium tetroxide, formaldehyde and glutaraldehyde singly and in mixtures was quantitatively assessed by viscosimetry, gel filtration and disc electrophoresis coupled with densitometry. The crosslinking of bovine serum albumin by pairs of fixatives was less than that produced by the most effective of the pair. After 5 min reaction osmium tetroxide was the most effective crosslinking agent according to viscosimetric experiments, but after one hour's reaction with bovine serum albumin, glutaraldehyde was revealed as the most effective crosslinking agent by gel filtration and electrophoresis.

A modified aldehyde perfusion technique for preventing certain artifacts in electron microscopy of the central nervous system.

Abstract: SUMMARY The production of vacuolated mitochondria and myelin figures can be markedly reduced with aldehyde perfusion fixation by perfusing a concentrated aldehyde solution before the conventional perfusate. A method is presented for accomplishing this with no practical time delay. Factors causing myelin figures and damaged mitochondria are discussed. Gum acacia helps prevent ‘washed-out’ cells and processes, and seems to aid myelin preservation. A clear solution is necessary for a good perfusion. Techniques for accomplishing this are presented. A concentrated formaldehyde solution perfused as a small volume immediately prior to the conventional perfusate causes alterations of the endoplasmic reticulum, including the subsurface cisterns, and an increase in numbers of spine apparatuses. Evidence is presented by using tubes of gelatin containing Schiff's reagent that formaldehyde is the fastest penetrating aldehyde but that it only fixes about half the distance it penetrates. Acrolein penetrates more rapidly than glutaraldehyde but fixes only as far as formaldehyde. Glutaraldehyde fixes as far as it penetrates.

Sterilization with glutaraldehyde

Abstract: STERILIZATION IS ACHIEVED BY CONTACTING A CONTAMINATED OBJECT WITH AN AQUEOUS ACID GLUTARALDEHYDE SOLUTION AT TEMPERATURES ABOVE ABOUT 45*C. THE STERILIZING ACTION MAY BE ENHANCED BY ULTRASONI ENERGY. STERILIZATION ALSO MAY BE ACHIEVED USING ULTRASONIC ENERGY AND AQUEOUS ALKALINE GLUTARALDEHYDE SOLUTION.

Cytochemical localization of myrosinase (β-thioglucosidase) in root tips ofSinapis alba

Abstract: A method for electron microscopic cytochemical localization of aβ-thioglucosidase (myrosinase) has been developed. Since sulphate is one of the products of the hydrolysis of sinigrin by myrosinase, it was felt that if the incubation was carried out in the presence of Pb++-ions an insoluble precipitate of electron-dense PbSO4 would be formed at the reaction sites. Following formaldehyde fixation a few different cell organelles in the extreme root tip ofSinapis alba showed reaction specificity for myrosinase but following glutaraldehyde fixation the enzymatic activity was inhibited. Biochemical tests of the isolated enzyme showed complete inhibition of the myrosinase by glutaraldehyde. Variations in the substrate concentration and incubation time indicated that the enzyme was confined to the dilated cisternae of the endoplasmic reticulum and in a limited extent to the mitochondria.

The effect of glutaraldehyde on light-induced H+ changes, electron transport, and phosphorylation in pea chloroplasts.

Abstract: This investigation has shown the following hierarchy of chloroplast reactions which were susceptible to increasing glutaraldehyde concentration given for 6 min at 0° C. (1) Cyclic and non-cyclic photophosphorylation was completely inhibited by 100 mM glutaraldehyde. (2) Reduction in the rate of H+ uptake, and increase in the rate of H+ efflux occurred to give a ratio uptake/loss of unity with 100 mM glutaraldehyde. (3) Volume fixation occurred at 200 mM glutaraldehyde. (4) Fixed chloroplasts were resistant to stimulation of H+ and electron transport by weak acid anions and uncouplers. (5) Light-induced electron-transport activity progressively decreased. About 35% inhibition of the basal (non-phosphorylating) rate and 60% inhibition of the uncoupled rate occurred on fixation. (6) The extent of the light-induced H+ changes were reduced only by about 10% upon fixation.

Extracellular space in frozen and ethanol substituted central nervous tissue.

Abstract: Cerebellar and cerebral cortices were frozen under various conditions; within 30 seconds of circulatory arrest, after eight minutes of asphyxiation, after ten minutes of perfusion with glutaraldehyde and after perfusion with this fixative and osmium tetroxide postfixation. Ethanol was used as the solvent in freeze substitution of these tissues. The resulting EMs closely resembled those of similar material freeze substituted in acetone. There were no differences in extracellular space even though differences have been reported between the space in EMs of conventionally fixed material dehydrated with ethanol or acetone.

Fixation of phycobiliproteins to photosynthetic membranes by glutaraldehyde.

Abstract: Treatment of intact cells of two unicellular red algae (Porphyridium spp.) and of an unicellular blue-green alga (Gloeocapsa alpicola) with glutaraldehyde (3% v/v) has only a slight effect on the absorption spectra of their photopigment systems, but stabilizes the normally labile physical association between phycobili-proteins and the chlorophyll-bearing thylacoids. On subsequent breakage of such cells, a substantial fraction of the total phycobiliprotein (30–70%) sediments in a sucrose gradient, in association with the chlorophyll-containing membrane fragments, from which it cannot be dissociated by treatment with detergents.

Factors affecting lead capture methods for the fine localization of rat lung acid phosphatase.

Abstract: Gomori's lead capture method for acid phosphatase localization was adapted for the electron microscope by Holt & Hicks (1961a). The method gave good results in rat liver, but poor tissue preservation with no reaction product in rat lung, and was, therefore, investigated in order to find the optimum conditions for the ultrastructural localization of rat lung acid phosphatase. The conditions investigated included the use of glutaraldehyde or depolymerized paraformaldehyde as the fixative, with and without dimethylsulphoxide; the effect of freezing the tissue; the pH of the incubation medium; and the use of glycerophosphate, naphthol AS-BI phosphate or α-naphthyl phosphate as substrates. Improved preservation of ultrastructure with increased yield of reaction product was obtained by prefixing lung in glutaraldehyde containing 10% dimethylsulphoxide, freezing the tissue and incubating at pH 5.7 with α-naphthyl phosphate. Tissue preservation was acceptable and dense deposits of reaction product occurred in lysosomal elements of all the alveolar cells and especially in macrophages. Deposits were also found closely associated with the lamellae of the inclusion bodies of Type II cells.

Leaf wax fine structure and ontogeny in Eucalyptus demonstrated by means of a specialized fixation technique

Abstract: SUMMARY The epidermal cells of Eucalyptus leaves are not well preserved by the conventional sectioning methods used for electron microscopy. More satisfactory preservation results from the use of an in vivo perfusion technique using glutaraldehyde or glutaraldehyde-formaldehyde mixtures. This technique preserves wax on the cuticle surface, rendering it insoluble in the organic solvents used for dehydration and embedding in epoxy resins. Using this method, no direct connection is apparent between leaf wax, cuticle, cell wall and cytoplasm. The Golgi bodies appear to produce vesicles which migrate only in the direction of the outer cell wall, and which might liberate wax precursors into the wall, from where they could diffuse through cuticular lamell to polymerize or oxidize at the leaf surface as waxes of characteristic morphology.

Fixation with aldehydes. Their usefulness for histological and histochemical studies in light and electron microscopy

Abstract: The suitability of four aldehydes (glutaraldehyde, acrolein, formaldehyde, hydroxyadipaldehyde) for histological and histochemical researches has been studied in the following experiments:

Preservation of fine Structures in Yeast by Fixation in a Dimethyl Sulfoxide-Acrolein-Glutaraldehyde Solution

Abstract: The primary fixative containing 2% acrolein, 2% glutaraldehyde in 50% aqueous dimethyl sulfoxide (DMSO) buffered at pH 7.4, was applied for 7 hr in the cold. After a short wash in 0.02 M s-collidine buffer, pH 7.4, containing 0.2 M sucrose and 0.001 M CaCl2, the yeast cells were postfixed in 3% OsO4 at pH 4.0 (veronal acetate buffer). This method preserves many cytoplasmic features such as lipid deposits and ribosomes which are usually destroyed by permanganate fixation. DMSO apparently acts as a permeating agent allowing maximum penetration of the cell wall by the fixative without disrupting cellular fine structure

On the stabilization by fixation of configurational states in beef heart mitochondria

Abstract: The energized configuration of the cristal membrane of beef heart mitochondria can be maintained only as long as oxygen is available for electron transfer. When the oxygen supply is exhausted, the membrane undergoes a transition to the nonenergized configuration. Since the exhaustion of the available oxygen supply is complete in 5–20 sec, it is impossible to apply the method of sedimenting the mitochondria prior to fixation for studying the energized configurational states of mitochondria. The direct addition of glutaraldehyde followed by osmium tetroxide to the mitochondrial suspension is the most effective way of freezing the configurational state of the cristal membrane. Fixation with glutaraldehyde appears to be complete within 1–2 sec even at 0°. Osmium tetroxide alone can also “freeze” the energized configuration by fixation but the concentration of the fixative is critical. The problem of capturing the configurational state applies not only to energized transitions (nonenergized to energized) but also to nonenergized transitions (orthodox to aggregated). The freezing by fixation of the cristal membrane in the aggregated configuration is best accomplished by the sequential use of glutaraldehyde and osmium tetroxide. When the levels of glutaraldehyde and osmium tetroxide are respectively too low or too high, the mitochondrion will undergo a transition from the aggregated to the orthodox configuration before fixation is complete. Light-scattering studies provide an independent method for monitoring configurational changes in mitochondria; these light-scattering measurements confirm that the conditions for fixation which lead to stabilization of the energized state as judged by electron microscopy, also show maintenance of configuration as judged by absence of light-scattering changes after the fixatives are introduced. Reagents used in negative staining will induce the geometrical form of the energized configuration of the mitochondrion even under nonenergizing conditions. These reagents are thus unsuitable for use in studies of configurational transitions in mitochondria.

Effect of glutaraldehyde on protoplasts of Bacillus megaterium.

Abstract: SUMMARY: Glutaraldehyde is a 5-carbon dialdehyde with a wide antimicrobial spectrum; its effectiveness is markedly increased by buffering, usually with sodium bicarbonate, between pH 7.5 and 8.5. Its properties as an antimicrobial agent and chemosterilizer have been reviewed by Rubbo, Gardner & Webb (1967), and it is used extensively as a fixative in electron microscopy. We suggested (Munton & Russell, 1970) that glutar-aldehyde acted on the wall of Escherichia coli, although other sites of action were also possible. We report here the effects of the dialdehyde on the stabilization of wall-less forms (protoplasts) with particular emphasis on their ability to withstand osmotic shock.

Electron microscope studies of deaminated and crosslinked collagen.

Abstract: SUMMARY Glutaraldehyde-crosslinked rat-tail collagen, compared with native fibres, showed an increase in the size of the light bands when examined in the electron microscope using a negative-staining technique. Collagen deaminated with nitrous acid gave similar patterns to native fibres and showed no change after treatment with glutaraldehyde. It was concluded that the increase in the size of the light bands is due to the formation of intermolecular crosslinks rather than charge neutralization of lysine amino groups.

Effect of glutaraldehyde fixation on the localization of various oxidative and hydrolytic enzymes in the brain of rhesus monkey, Macaca mulatta.

Abstract: Histochemical investigations have been made on the localization of certain oxidative and hydrolytic enzymes in the different areas of rhesus monkey brain using unfixed, freshfrozen tissue and 3% glutaraldehyde-fixed material After glutaraldehyde fixation, the oxidative enzymes lose most of their activity normally demonstrable in the fresh-frozen section The hydrolytic enzymes are somewhat resistant to fixation but also lose about half of the enzyme activity observed after no fixing procedure The glycogen is better preserved in the glutaraldehyde-fixed material compared to fresh-frozen or even formaldehyde-fixed tissue The significance of these observations is discussed in relation to glutaraldehyde as a fixative of choice in electron histochemistry

Desensitized allergy inducing material

Abstract: The allergy producing properties of the material are lowered by inter and/or intra molecular action. Pref. the material is reacted with a polyaldehyde, polyketone, carbodiimide, epihalohydrin, or inorganic cyanate in acid medium, to give a modified material insoluble or barely soluble in water. Cpds. esp. used are glutaraldehyde, phenylglyoxal, 2-nitroindane-1,3-dione at pH 4-8 or, 1-cyclohexyl-3-(2-morpholino-ethyl)-carbodiimide metho-p-toluenesulphonate, or KCN at pH is approx. 5. Pref. the allergy inducing material is pollen(s).

Isolation of Anti-polysaccharide Antibodies with Glutaraldehyde Cross-linked Lipopolysaccharides

Abstract: IMMUNOADSORBANTS are used chiefly for the isolation of antibodies against protein antigens. Glutaraldehyde has already been successfully used as a cross-linking agent to convert carboxypeptidase A1, trypsin2 and protein antigens3 into insoluble derivatives retaining their specific biological properties. Few attempts have been made to prepare immunoadsorbents from substances other than proteins4,5. In so far as lipopolysaccharides have not been insolubilized, we have attempted their cross-linkage to develop a cross-linking procedure, using glutaraldehyde.

On the variability of spherosome-like bodies in Phaseolus vulgaris.

Abstract: Root and shoot apices and primary leaves of 3- to 4-day-old seedlings of Phaseolus vulgaris L. were examined in the electron microscope after fixation with (a) glutaraldehyde followed by osmium tetroxide, (b) glutaraldehyde followed by potassium permanganate, (c) osmium tetroxide alone, and (d) potassium permanganate alone. The distribution, shape, and substructure of the spherosome-like bodies in the cytoplasm varied markedly depending upon the tissue, its age, and the fixation used. Shapes varied from stellate through polygonal to spherical. The electron density of the interior of the organelles varied from uniformly dark after osmium tetroxide fixation to almost none after permanganate fixation. In addition to differences caused by fixatives, marked variation of the electron density of the same organelles with identical fixation was observed. Structural, and possibly physiological, heterogeneity seems to be characteristic of spherosomes but in spite of their variability, they may be recognized in the e...

Stable solutions of melamine-urea-formaldehyde condensates containing a stabilizing aldehyde and processes for their preparation

Abstract: STABLE AQUEOUS ALKALINE SOLUTIONS OF CURABLE MELAMINEUREA-FORMALDEHYDE CONDENSATES SUITABLE FOR ADHESIVES AND FOR TREATMENT OF PAPER AND TEXTILES ARE PREPARED BY INCORPORATING 0.1 TO 5 MOLES, PER MOLE OF MELAMINE, OF A STABILIZING ALDEHYDE SELECTED FROM THE GROUP OF ACETALDEHYDE, GLYOXAL, PROPIONALDEHYDE AND GLUTARALDEHYDE.

Glutaraldehyde Fixation of Corneal Acid Mucopolysaccharides

Abstract: (1) 24 hours fixation of rabbit corneae with 6% glutaraldehyde-sodium phosphate was without any significant effect of the corneal acid mucopolysaccharides (AMPS) estimated by the determination of hexo