Effect of bromidehypochlorite bactericides on microorganisms.
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A new principle in compounding stable, granular bactericidal products led to unique combinations of a water-soluble inorganic bromide salt with a hypochlorite-type disinfectant of either inorganic or organic type. Microbiological results are shown for an inorganic bactericide composed of chlorinated trisodium phosphate containing 3.1% "available chlorine" and 2% potassium bromide, and for an organic bactericide formulated from sodium dichloroisocyanurate so as to contain 13.4% "available chlorine" and 8% potassium bromide. Comparison of these products with their nonbromide counterparts are reported for Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Streptococcus lactis, Aerobacter aerogenes, and Proteus vulgaris. Test methods employed were the Chambers test, the A.O.A.C. Germicidal and Detergent Sanitizer-Official test, and the Available Chlorine Germicidal Equivalent Concentration test. The minimal killing concentrations for the bromide-hypochlorite bactericides against this variety of organisms were reduced by a factor 2 to 24 times those required for similar hypochlorite-type disinfectants not containing the bromide. (+info)
Effect of antisympathomimetic drugs on the plasma concentrations of catechol amines.
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Intravenous injection of phenoxybenzamine, choline 2,6-xylyl ether bromide (xylocholine, TM 10), piperoxane or dihydroergotamine increases the vasopressor activity of blood plasma, collected from cats under chloralose anaesthesia. The increased vasopressor activity that follows the administration of piperoxane is due to an increase of adrenaline and noradrenaline in the plasma. Cross-circulation experiments show that catechol amines are liberated from the spleen by piperoxane. (+info)
THE METABOLISM OF THE VOLATILE AMINES: V. THE SPONTANEOUS FORMATION OF AMMONIA IN SHED BLOOD ON STANDING.
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The spontaneous formation of ammonia which takes place when shed whole blood is allowed to stand was investigated and was found to consist of a complex series of reactions. The rate of ammonia formation was initially rapid but gradually slowed, and the maximum amount of ammonia was formed after a period of about seven days. Both the type of anticoagulant used and the availability of oxygen influenced the rate of ammonia formation. This reaction was inhibited when the blood was kept frozen but it was found that the measurement of the ammonia content of frozen and thawed blood was both difficult and inaccurate. Dilute solutions of zinc bromide partially inhibited this reaction.Compounds which give rise to ammonia were found to be present in both plasma and erythrocytes, although the deamidation reactions took place solely within the erythrocytes. The total amount of ammonia formed depended on the hemoglobin content of the blood and varied in certain patients suffering from erythrocyte disorders. (+info)
ANION REQUIREMENTS FOR GASTRIC ACID SECRETION.
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The rate of hydrochloric acid production by isolated, bullfrog gastric mucosae depends critically on the supply of chloride ion to the serosal surface. Secretion of acid is negligible if chloride is completely replaced by glucuronate and gluconate ion. The experimental evidence indicates that the rate of acid secretion may be regarded as a reaction velocity, depending on chloride concentration in a manner closely resembling Michaelis-Menten kinetics. Bromide and iodide ions substitute, in varying degree, for chloride as substrate. A familiar inhibitor of gastric acid production, thiocyanate ion, appears to act by competition with chloride in a reaction leading to the formation of acid. This reaction is included in a hypothetical reaction cycle, generalized from the redox model for gastric acid production. Under certain conditions, the model predicts a dependence of secretion rate on chloride supply of the Michaelis-Menten type, as was observed. (+info)
THE EFFECTS OF ALKALI METAL CATIONS AND COMMON ANIONS ON THE FROG SKIN POTENTIAL.
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The effects on the potential difference across isolated frog skin (R. catesbeiana, R. pipiens) of changing the ionic composition of the bathing solutions have been examined. Estimates of mean values and precision are presented for the potential changes produced by substituting other alkali metal cations for Na at the outside border and for K at the inside border. In terms of ability to mimic Na at the outside border of bullfrog skin, the selectivity order is Li > Rb, K, Cs; at the outside border of leopard frog skin, Li > Cs, K, Rb. In terms of ability to mimic K at the inside border of bullfrog and leopard frog skin: Rb > Cs > Li > Na. Orders of anion selectivity in terms of sensitivity of the potential for the outside border of bullfrog skin are Br > Cl > NO(3) > I > SO(4), isethionate and of leopard frog skin are Br, Cl > I, NO(3), SO(4). An effect of the solution composition (ionic strength?) on the apparent Na-K selectivity of the outside border is described. The results of the investigation have been interpreted and discussed in terms of the application of the constant field equation to the Koefoed-Johnsen-Ussing frog skin model. These observations may be useful in constructing and testing models of biological ionic selectivity. (+info)
Differential chemical protection of mammalian cells from the exotoxins of Corynebacterium diphtheriae and Pseudomonas aeruginosa.
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Many drugs or chemicals had markedly different effects on the cytotoxicity induced by Pseudomonas aeruginosa exotoxin A (PE) or Corynebacterium diphtheriae exotoxin (DE). The glycolytic inhibitor NaF protected cells from DE but potentiated the cytotoxicity of PE. Another energy inhibitor, salicylic acid, also protected cells from DE but had no effect with PE. Colchicine and colcemid did not affect the cytotoxicity of either toxin. Cytochalasin B exhibited a modest protection from DE but no effect with PE. Ouabain, a specific inhibitor of the Na+, K+-dependent adenosine 5'-triphosphatase (ATPase), did not affect the cytotoxicity of either toxin. Ruthenium red, a specific inhibitor of the Ca2+, Mg2+,-dependent ATPase, conferred marked protection from DE-induced cytotoxicity but did not affect PE-induced cytotoxicity. A number of local anesthetics were tested, and they too presented differential results with PE and DE. Most chemicals that affected toxin-induced cytotoxicity had little or no influence on the in vitro adenosine 5'-diphosphate-ribosylation catalyzed by either toxin. This work presents further evidence that PE and DE have different mechanisms of intoxication and suggests that these differences lie in the attachment or internalization stages of intoxication. (+info)
INFLUENCE OF SOME IONS ON THE MEMBRANE POTENTIAL OF ASCARIS MUSCLE.
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The influence of several ions on the membrane potential of the somatic muscle of Ascaris has been investigated by changing their concentration in the surrounding solution. When [K](o) is increased at the expense of [Na](o) leaving [Cl](o) constant, the membrane potential is first seen to increase. [K](o) higher than 45 mM reduces the membrane potential with a slope of 23 mv for a tenfold change in [K](o). However, when [K](o) is increased keeping [Na](o) and [Cl](o) low and constant, the line relating the membrane potential with log [K](o) has a slope of almost 50 mv. If [Cl](o) is reduced in the absence of external Na, after the [K](o) is increased to 45 mM, the membrane potential decreases with a slope of 59 mv per tenfold change in [Cl](o) in close agreement with the Nernst equation. If Cl(-) is replaced by SO(4) (2-), a depolarization is produced, while chloride replacement by NO(3) (-), Br(-), and I(-) results in a hyperpolarization of the membrane. Removal of the external Na(+) ions increases the average membrane potential by 17 mv. (+info)
THE EFFECTS OF VARIOUS IONS ON RESTING AND SPIKE POTENTIALS OF BARNACLE MUSCLE FIBERS.
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Effects of monovalent cations and some anions on the electrical properties of the barnacle muscle fiber membrane were studied when the intra- or extracellular concentrations of those ions were altered by longitudinal intra-cellular injection. The resting potential of the normal fiber decreases linearly with increase of logarithm of [K(+)](out) and the decrement for a tenfold increase in [K(+)](out) is 58 mv when the product, [K(+)](out) .[Cl(-)](out), is kept constant. It also decreases with decreasing [K(+)](in) but is always less than expected theoretically. The deviation becomes larger as [K(+)](in) increases and the resting potential finally starts to decrease with increasing [K(+)](in) for [K(+)](in) > 250 mM. When the internal K(+) concentration is decreased the overshoot of the spike potential increases and the time course of the spike potential becomes more prolonged. In substituting for the internal K(+), Na(+) and sucrose affect the resting and spike potentials similarly. Some organic cations (guanidine, choline, tris, and TMA) behave like sucrose while some other organic cations (TEA, TPA, and TBA) have a specific effect and prolong the spike potential if they are applied intracellularly or extracellularly. In all cases the active membrane potential increases linearly with the logarithm of [Ca(++)](out)/[K(+)](in) and the increment is about 29 mv for tenfold increase in this ratio. The fiber membrane is permeable to Cl(-) and other smaller anions (Br(-) and I(-)) but not to acetate(-) and larger anions (citrate(-), sulfate(-), and methanesulfonate(-)). (+info)