Sodium Ethylenediaminetetraacetic Acid Research Articles

Hyperpolarization/Depolarization on Human Spermatozoa

The accumulation of the lipophilic cation radiolabeled triphenylmethylphosphonium (TPMP+) was utilized to determine the resting membrane potential across the plasma membrane (psi) of human sperm. Washed sperm were suspended and incubated in low-K+ and high-K+ medium and allowed to take up the cation to a steady state (20 min at 37 degrees C). By using this differential, the value obtained was inserted in the Nernst equation and the value yielded a psi of -69 +/- 2 mV. When the Na+ or K+ concentration is high in the medium, the accumulation of TPMP+ in the membrane sperm cells was increased or decreased, respectively, inducing hyperpolarization and depolarization of the membrane 20% and 85%, respectively. The presence of divalent cations Zn++ and Mg++ in the incubation medium both induced a hyperpolarization of 10% and 8.6%, respectively. The addition of specific reagents such as p-chloromercuribenzenosulfonate and ethylenediaminetetraacetic acid sodium salt both decreased the psi 35% and 58%, respectively. The agents acting on the sperm cell membrane, such as dithiothreitol and progesterone, both induced hyperpolarization and depolarization of the membrane 16% and 40%, respectively. The presence of propranolol and L-alpha-lysophosphatidylcholine, which affect the ionic gradients present across the plasma membrane, both induced a depolarization from 43% and 92%, respectively. Finally the psi was glucose-dependent. The result of these studies was that, by the use of agents causing hyperpolarization or depolarization, we obtained changes in the psi of -83.4 +/- 2.2 mV, until -6 +/- 0.6 mV changes of -76.8 +/- 2 mV translated across the sperm cell membrane.

Use of EDTA for chelating toxic metals inhibiting BOD measurements

The trans-isomer of sodium ethylenediamine-tetraacetic acid (EDTA) was used to chelate metal ions known to inhibit accurate determination of BOD of wastewater. The results showed that as much as 5 mg Cu(II) and 6 mg Zn present in a litre of poultry wastewater were effectively chelated by 1 ml of 0·1 m EDTA so that the metals had no suppressive effect on the BOD values.

Decreased stability and structural heterogeneity of the residual platelet glycoprotein IIb/IIIa complex in a variant of Glanzmann's thrombasthenia.

A patient is described with a disturbance of platelet function comparable to that in Glanzmann's thrombasthenia. Platelet aggregation and binding of fibrinogen to the patient's platelets were defective and thrombin-induced clot retraction was absent. The platelet fibrinogen content was only moderately reduced. As measured by monoclonal antibody binding in the presence of divalent cations, the platelets contained about 15% of the normal amount of GPIIb and GPIIIa and only 6% of the normal amount of intact GPIIb/IIIa complex. The residual GPIIb/IIIa complex exhibited a decreased stability as shown by the lack of binding of a complex-dependent anti-GPIIb/IIIa antibody to platelets incubated with ethylene diamine tetraacetic acid (EDTA) at 22 degrees C. Crossed immunoelectrophoresis (CIE) in the presence of divalent cations showed partial dissociation of GPIIb/IIIa as well as the presence of two forms of the residual intact GPIIb/IIIa complex. In addition, both CIE in the presence of the EDTA and two-dimensional sodium dodecyl sulphate (SDS) gel electrophoresis showed the presence of two forms of GPIIb. This form of thrombasthenia is characterized by a defective platelet function, a marked reduction of GPIIb and GPIIIa, decreased stability of the residual GPIIb/IIIa complex and structural heterogeneity of GPIIb.

Cell Walls of Tobacco Cells and Changes in Composition Associated with Reduced Growth upon Adaptation to Water and Saline Stress

The relative mass of the cell walls of tobacco (Nicotiana tabacum L.) cells adapted to grow in medium containing 30% polyethylene glycol 8000 or 428 millimolar NaCl was reduced to about 50% of that of the walls of unadapted cells. Cellulose synthesis was inhibited substantially in adapted cells. The proportions of total pectin in walls of unadapted and adapted cells were about the same, but substantial amount of uronic acid-rich material from walls of cells adapted to either NaCl or polyethylene glycol was more easily extracted with cold sodium ethylenediamine tetraacetic acid solutions (NM Iraki et al. [1989] Plant Physiol. 91: 39-47). We examined the linkage composition of the pectic and hemicellulosic polysaccharides to ascertain chemical factors that may explain this difference in physical behavior. Adaptation to stress resulted in the formation of a loosely bound shell of polygalacturonic acid and rhamnogalacturonan. Pectins extracted from walls of adapted cells by either cold sodium ethylenediamine tetraacetic acid or hot ammonium oxalate were particularly enriched in rhamnose. Compared to pectins of unadapted cells, rhamnosyl units of the rhamnogalacturonans of adapted cells were more highly substituted with polymers containing arabinose and galactose, but the side groups were of greatly reduced molecular size. Possible functional roles of these modifications in cell wall metabolism related to adaptation to osmotic stress are discussed.

Effect of calcium-binding additives on ventricular fibrillation and repolarization changes during coronary angiography

Ventricular fibrillation during coronary angiography with Renografin-76 (meglumine sodium diatrizoate) has been attributed to the calcium-binding additives sodium citrate and sodium ethylenediaminetetraacetic acid (EDTA), which may produce repolarization changes manifested as prolongation of the QT interval. Angiovist-370 is a newer form of meglumine sodium diatrizoate that contains calcium EDTA as its additive and thus has a decreased calcium-binding effect. Eight hundred sixteen patients were prospectively randomized to receive either Renografin-76 or Angiovist-370. Ventricular fibrillation occurred in 10 of 410 patients receiving Renografin-76 and in 0 of 406 patients given Angiovist-370 (p less than 0.0005). Clinical data were analyzed without knowledge of other data in the 10 patients treated with Renografin-76 who had ventricular fibrillation (Group I), 103 randomly selected patients who also received Renografin-76 but had no ventricular fibrillation (Group II) and 108 randomly selected patients given Angiovist-370 (Group III). Of several variables examined, only the QT interval differentiated patients receiving Renografin-76 and Angiovist-370. The mean corrected QT interval (QTc interval) before coronary angiography was slightly but not significantly (p = 0.7) higher in Group I than in Groups II and III. Ten seconds after the first left coronary artery injection it was more prolonged in Groups I and II (0.552 and 0.561 second, respectively) than in Group III (0.448 second) (p less than 0.00005). Similarly, 10 seconds after the first right coronary artery injection it was significantly longer in Groups I and II (0.545 and 0.544 second) than in Group III (0.477 second) (p less than 0.00005).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of environmental parameters on the elimination of cadmium by eastern oysters, Crassostrea virginica.

Laboratory studies were conducted to test the effects of salinity, humic acid, and temperature on the rate of elimination of109Cd from laboratory-dosed juvenile oysters,Crassostrea virginica. After 140 days, oysters maintained at 34 parts per thousand (ppt) salinity retained 67% of the109Cd dose (CPM), oysters in 20 ppt salinity retained 72% and those in 6 ppt salinity retained 80%. The presence of humic acid in 14 ppt salinity water enhanced the amount of109Cd eliminated in 140 days relative to oysters in control tanks without humic acid: oysters exposed to 10 parts per million (ppm) humic acid retained 65%, oysters exposed to 1 ppm humic acid retained 67%, controls retained 72%. Temperature had a significant effect on the rate of Cd elimination. Oysters held at 28°C and 20 ppt for 28 days retained 75%, oysters at 20°C and 20 ppt retained 81% and those at 12°C and 20 ppt retained 88% of109Cd dose. The effects of a strong Cd-chelator, ethylenediamine tetraacetic acid-sodium salt (EDTA), were compared with those of the relatively weaker chelator, humic acid, on the rate of Cd elimination by oysters. No difference was observed between the two chelators over a 28 day depuration period. Cadmium concentrations were monitored in the water and Cd, Cu, Zn, Mg, and Fe concentrations were determined in the animals on the final day of the studies. Particle clearance assays were performed to determine if the rate of filtration by the oysters held in each of the test treatments correlated with the rates of Cd depuration. No direct correlation was observed.

Liquid Chromatographic Determination of the Composition of Thiacetarsamide Solutions

Abstract Sodium thiacetarsamide in solution is a mixture of p-arsenosobenzamide and thiacetarsamide as determined by two reverse phase liquid chromatographic (LC) procedures with the following mobile phases: Procedure I: methanol:0.25 mM sodium phosphate and 0.0125 mM sodium ethylenediaminetetraacetic acid aqueous buffer, pH 7 (15:85); and procedure II: tetrahydrofuran:2.5 mM sodium metabisulfite and 0.5 mM phosphoric acid aqueous buffer, pH 3 (5:95). Procedure I separated p-arsenosobenzamide from unretained thiacetarsamide and degradation products. Procedure II retained and separated thiacetarsamide, p-arsenosobenzamide, and degradation products. Both procedures inhibited on-column hydrolysis of thiacetarsamide to p-arsenosobenzamide and allowed two independent estimations of the p-arsenosobenzamide content of thiacetarsamide solutions. Only p-arsenosobenzamide and unidentified degradation products were detected when sodium thiacetarsamide-p-arsenosobenzamide solutions were stored for 6 months at room temperature. However, the refrigerated solutions were composed of thiacetarsamide and p-arsenosobenzamide plus trace amounts of unidentified substances. Under strongly basic conditions, thiacetarsamide hydrolyzed to p-arsenosobenzamide, which later degraded to unknown compounds. To stabilize and maintain a relatively constant composition, sodium thiacetarsamide-p-arsenosobenzamide solutions must be refrigerated and protected from light and oxygen.

Direct pharmacologic and osmolal effects of contrast media on the mechanics of heart muscle isolated from cats

We studied 56 right ventricular papillary muscles isolated from cats to determine whether the direct mechanical effects of contrast media are due to their pharmacologic action or to the hyperosmolality caused by them. A 10% solution of Renografin-76 abruptly decreased force 22% below control, then slowly increased it to 22% above control. To elucidate these changes we also studied: (1) Renografin-60 (lower concentration of diatrizoate); (2) meglumine and diatrizoate; (3) meglumine alone; (4) diatrizoate sodium; (5) ethylene diamine tetra-acetic acid (EDTA) (same concentration as in Renografin-76); (6) sucrose to increase osmolality; and (7) Amipaque (metrizamide), a contrast medium without meglumine or diatrizoate. All solutions containing meglumine, and EDTA alone decreased force. Diatrizoate sodium also decreased force initially, presumably due to the high sodium concentration. Meglumine alone decreased force abruptly and substantially. In contrast, metrizamide and 100 mmol sucrose only increased force. Thus, the abrupt decrease in force was caused by the pharmacologic action of meglumine, EDTA, or high sodium in the contrast media, whereas the slow increase in force was caused by hyperosmolality.

Study of the electrooxidative behaviour of 5-hydroxyindole-3-acetic acid, 5-hydroxytryptophan and serotonine in the presence of sodium ethylenediaminetetraacetic acid

The great instability of the indole derivatives 5-hydroxytryptophan (5-HTP), serotonine (5-HT) and 5-hydroxyindole-3-acetic acid (5-HIAA) in strong acid medium and the protective role of sodium ethylenediaminetetracetate (EDTA H 2Na 2) could be explained by their electrooxidative behaviour on a carbon paste electrode. Voltamperometric curves obtained in a 1–8 pH range show that oxidation occurs in two irreversible steps; the mechanism is more complex than a simple electron transfer. For the three molecules, new redox couples have been detected on cyclic voltammograms at lower potentials than the parent compound, indicating that more easily oxidized derivatives are formed. On the other hand, the anodic oxidation of EDTA H 2Na 2 has been investigated and in the present case the molecule is not acting by complexing metal traces but should actually be considered a competitive agent preventing the second oxidation step of the indole derivatives.

Effects of storage times and temperatures on T3, T4, LH, prolactin, insulin, cortisol and progesterone concentrations in blood samples from cows.

Little is known about stability of hormones in blood samples stored under various conditions. This study was conducted to examine stability of triiodothyronine (T3), thyroxine (T4), luteinizing hormone (LH), prolactin, insulin, cortisol and progesterone in blood and serum samples. Experiment 1 was designed to determine if concentrations of these hormones were affected by exposure to cellular elements of anticoagulated and coagulated blood when stored at 4 C and room temperature (22 to 26 C). Jugular venous blood was collected from six diestrous Holstein cows into evacuated bottles containing sodium ethylenediaminetetraacetic acid (EDTA), heparin or no anticoagulant. Subsamples of EDTA-treated and heparinized blood were stored .25, .5, 1, 2, 4, 8, 24 and 72 h at 4 C or room temperature. Subsamples of blood without anticoagulant were stored in polypropylene tubes (clot tubes) or serum separator tubes for 1, 2, 4, 8, 24 ad 72 h. Mean concentrations of T3, T4, LH, prolactin and cortisol did not change in plasma or serum from either of the four types of samples stored at 4 C or room temperature for 72 h. The mean insulin concentration decreased 18% by 72 h in serum from serum separator tubes stored at room temperature. At 4 C, mean progesterone concentrations decreased 55% by 24 h and 73% by 72 h in plasma from EDTA-treated blood; 41% by 72 h in serum from clot tubes, and 26% by 24 h and 36% by 72 h in serum from serum separator tubes.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of Prussian blue and sodium-ethylenediaminetetraacetic acid on the faecal and urinary elimination of thallium by the dog

After oral administration of sublethal doses of thallium (lower than 10 mg/kg) to dogs, 75.5 +/- 3.9 per cent of the dose was eliminated from the body--47 per cent faecal and 28 per cent urinary. Cumulative excretion reached 50 and 70 per cent after 10 and 25 days respectively, and was almost complete after 75 days. This was slightly lower at higher doses. The total body-burden of thallium, calculated from the cumulative excretion, decreased exponentially for at least the first 40 days with a half-time (T 1/2) of 6.5 days. Oral doses of Prussian blue after 10 days resulted in an acceleration of the thallium elimination from the body (T 1/2 2.5 days), an increase of the faecal (49 per cent) and a decrease of the urinary excretion (18 per cent). Nevertheless, the cumulative faecal and urinary thallium excretion was not influenced. Minor transitory influences of Prussian blue on the faecal thallium excretion could be observed up to day 26. After 40 days, Prussian blue could no longer influence the faecal thallium excretion. At no time did sodium-ethylenediaminetetraacetic (Na2EDTA) acid significantly change faecal or urinary thallium excretion.

A dendrogram of plant viruses

To facilitate the recognition of plant viruses with similar characteristics a dendrogram of characterized viruses was constructed. The sequence of criteria included: type of nucleic acid; single or double stranded; presence or absence of lipid envelope; helical or nonhelical symmetry; and divided or single genome. Nonhelical RNA viruses with divided genomes were further divided into viruses with one or more than one capsid size. Those with one capsid size were subdivided into viruses with one or more than one sedimenting component. Nonhelical RNA viruses with a single genome were divided according to their RNA size, and their sensitivity to sodium dodecyl sulfate and ethylenediaminetetraacetic acid.

Partial purification and properties of a β-glucosidase from Erwinia herbicola Y46

A constitutive beta-glucosidase of Erwinia herbicola Y46 was studied as a prerequisite to an assessment of its significance in the release of bacteriotoxic aglycones from plant beta-glucosides, and the possible effects of the aglycones on the course of such plant diseases as "fire-blight". The enzyme was purified 86.5-fold from crude extracts of cells grown on yeast beef broth. Ammonium sulfate precipitation, DEAE-cellulose fractionation, and gel filtration through Sephadex G-100 resulted in a preparation having one peak of activity on isoelectrofocussing, on gel filtration through Sephadex G-200, and on polyacrylamide gel electrophoresis. The latter techniques demonstrated, in addition to the major protein band associated with activity, a single minor impurity. The enzyme was active against p-nitrophenyl-beta-glucoside (p-NPG) and phloridzin, but showed only very slight activity against salicin and arbutin, and no detectable activity against beta-methyl-D-glucoside, cellobiose, lactose, and esculin. The production of beta-glucosidase was maximum at the late log phase of growth on yeast beef broth medium and declined somewhat thereafter. The incorporation of inducers (carbohydrates) in defined basal medium resulted in only small variations in specific activity in the resulting cells; The activity (p-NPG substrate) was not inhibited by D-glucose, phloretin, esculin, salicin, arbutin, lactose, or cellobiose, but was slightly inhibited by 1.0 mM phloridzin. Slight inhibition was observed in the presence of sulfhydryl reagents (iodoacetamide, p-chloromercuribenzoate), but sodium azide, ethylene-diaminetetraacetic acid, Cu2+, and Zn2+ ions produced no effect. The activity was stable, in both crude and purified preparations, over the pH ranges 6.0-7.5 (100% activity) and 4.5-greater than 8.5 (50% activity). The enzyme retained 80% activity after 30 min at 50 degrees C, but only 25% after 30 min at 60 degrees C. The enzyme had a mean K-m value (phloridzin) of 1.35 times 10-4 M, an isoelectric point of 4.75, a molecular weight, determined by Sephadex G-200 gel filtration, of about 122 000, and an optimum pH for activity of 6.5-7.0.

Über die Einwirkung Proteolytischer aktivität aus der kulturlösung von Bacillus subtilis auf die entkalkten Zahngewebe

From the culture medium of the Bacillus subtilis strain ATCC 6633 the proteolytic enzyme activity was isolated by ammonium sulphate precipitation and acetone treatment. In the case of the isolated activity it is a question of a serine protease with a pH optimum of 10, which is inhibited by diisopropyl fluoro-phosphate and sodium ethylene diamine tetra-acetic acid and is not influenced by o-phenanthroline. With the enzyme preparations thus obtained, decalcified sections of caries-free human teeth were incubated at pH 7.0 and 37 °C both with and without di-isopropyl fluoro-phosphate. Under the influence of the enzyme action there were changes in the matachromatic structures and finally the disintegration of the decalcified dental tissue. Propitious points of attack are the cement-dentine boundary and the central sections of the globuli. The isolated enzyme thus leads to the same decomposition phenomena as the direct incubation with Bacillus subtilis. With this enzymatic decomposition of the dental tissue, determinable quantities of nitrogen are released biochemically in the incubation solution. It is assumed that the hydrolysed substance is a glycoproteid with a non-collagenic protein component.

Parathyroid hormone secretion in familial vitamin-D-resistant rickets.

Parathyroid function was determined in four adults and one child with familial vitamin-D-resistant rickets. All subjects demonstrated hypophosphatemia, whereas the total serum calcium and magnesium showed no consistent pattern as compared to normal subjects. Peripheral parathyroid hormone concentrations were elevated in all subjects. Hypocalcemia induced by sodium ethylenediaminetetra-acetic acid in three adults produced a greater increase in parathyroid hormone secretion than in normal subjects. The increased concentrations of parathyroid hormone, both basal and during induced hypocalcemia, are consistent with Albright's hypothesis that the hyperparathyroidism in these subjects is due to decreased absorption of calcium from the gastrointestinal tract. (N Engl J Med 289:941–945, 1973)

Skin decontamination in presence of thallium-204.

Decontamination tests on rat skins contaminated with Tl/sup 204/ sulfate solution were conducted with three decontaminating solutions: soap, sodium ethylenediamine tetraacetic acid, and calcium ethylenediamine tetraacetic acid. The results indicate that a solution of water and soap is the most efficient agent. A device is described for continuousflow decontamination with minimum rubbing, time, and spreading of contaminant. (D.J.C.)