Effect of glucose and inosine triphosphate on seasonal variation of gastric acid production in Rana pipiens

1959 ◽  
Vol 196 (5) ◽  
pp. 975-978 ◽  
Author(s):  
Sherwin Mizell
Keyword(s):  
Seasonal Variation ◽  
Gastric Acid ◽  
Acid Production ◽  
Rana Pipiens ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Hydrogen Ion Concentration ◽  
Total Chloride ◽  
Effect Of Glucose

The production of acid in vitro by the gastric mucosa of 375 Rana pipiens was studied over a period of 13 months. The frogs were kept at 21°C and histamine was used to induce secretion. Four conditions were studied: a) control, no substrate added to the nutrient solution; b) 10 mm glucose added; c) 0.6 µm inosine triphosphate (ITP) added and d) 10 mm glucose and 0.6 µm ITP added. For each mucosa the change in hydrogen ion concentration (ΔpH), titrable acidity and total chloride produced were measured. The results indicate that the seasonal variation in gastric acid production is due, in part, to a variation in the availability of substrate normally present.

570. A medium for the simultaneous enumeration and preliminary identification of milk microflora

1955 ◽  
Vol 22 (1) ◽  
pp. 43-47 ◽  
Author(s):  
Kathleen O. Donovan ◽  
J. M. Vincent
Keyword(s):  
Acid Production ◽  
Skim Milk ◽  
Biochemical Properties ◽  
Viable Count ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Hydrogen Ion Concentration ◽  
Pasteurized Milk ◽  
Preliminary Identification

A medium has been developed that permits the viable count of milk bacteria to be combined with the determination of biochemical properties likely to be important in milk itself. This has involved the modification of standard glucose-tryptone skim-milk agar by incorporation of two indicators to detect alkali as well as acid production, substitution of lactose for glucose, and increasing the quantity of skim milk for the detection of proteolysis and casein precipitation. The medium has proved particularly valuable in the study of the thermoduric flora of pasteurized milk. The phenomenon of casein precipitation is, however, less reliably determined than are changes in hydrogen-ion concentration and proteolysis.

Seasonal variation in some characteristics of seminal plasma of Sudan Desert sheep in the tropics

1982 ◽  
Vol 99 (1) ◽  
pp. 45-49 ◽  
Author(s):  
K. A. A. Galil ◽  
A. K. A. Galil
Keyword(s):  
Seasonal Variation ◽  
Seminal Plasma ◽  
Rainy Season ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Monthly Variation ◽  
Hydrogen Ion Concentration ◽  
Tropical Conditions ◽  
Hot Weather ◽  
The Tropics

SUMMARYSome androgen-dependent constituents of seminal plasma of Sudan Desert rams were measured during the hot dry summer, the hot rainy season and the winter under tropical conditions in the Sudan. Higher concentrations of both fructose and citric acid were obtained between July and October during the rainy season and low values between January and April during winter, with marked monthly and seasonal variation in both characters. Considerable monthly variation in the hydrogen-ion concentration of semen was obtained with lower values between August and January and higher values between February and July. The androgenic status of the animals appears not to be decreased during the hot weather, but no explanation can be offered for the decrease during the winter.

Effect of norepinephrine on myocardial intracellular hydrogen ion concentration

1975 ◽  
Vol 229 (2) ◽  
pp. 344-349 ◽  
Author(s):  
KM Riegle ◽  
RL Clancy
Keyword(s):  
Metabolic Acidosis ◽  
Respiratory Acidosis ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Beta Blockade ◽  
Hydrogen Ion Concentration ◽  
Rat Hearts ◽  
Buffer Value

The effect of norepinephrine (NE) on the intracellular hydrogen ion concentration [H+]i of isolated rat hearts perfused with a modified Krebs-Henseleit solution (SHS) was determined. The [H+]i was calculated with the [14C]-dimethyloxazolidinedione method. Respiratory or metabolic acidosis was produced by equilibrating the KHS with 20% C02 or decreasing the [HC03-] of the KHS, respectively. Three types of experiments were carried out: 1) beta blockade--MJ 1999 (Sotalol) was added to the KHS; 2) control--no pharmacological treatment; and 3) NE-norepinephrine was added to the KHS. The effective CO2 buffer values (delta[HC03-]i/deltapHi) during respiratory acidosis were: beta blockade, 11; control, 35; and NE, 84. The production of metabolic acidosis resulted in the following [H+]i changes: beta blockade, 52 mM; control, 60 nM; and NE 7 nM. These results suggest that NE markedly attenuates the changes in [H+]i accompanying respiratory and metabolic acidosis and may account in part for previous observations that the effective C02 buffer value of cardiac muscle in vivo is greater than that in vitro.

scholarly journals STUDIES ON THE PHYSICAL AND CHEMICAL PROPERTIES OF THE VIRUS OF FOOT-AND-MOUTH DISEASE

1927 ◽  
Vol 45 (5) ◽  
pp. 833-848 ◽  
Author(s):  
Peter K. Olitsky ◽  
Louis Boëz
Keyword(s):  
Active Agent ◽  
Chemical Properties ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Basic Medium ◽  
Hydrogen Ion Concentration ◽  
Foot And Mouth

No multiplication of the virus in vitro was observed. We have found, however, that the optimum conditions necessary for the preservation of the virus in artificial media are as follows: The hydrogen ion concentration of the medium should be 7.5 to 7.6, not only at the beginning, but, and more important, at the conclusion of the period of observation. A strict anaerobic atmosphere is also favorable, as is a temperature below 37°C. A semisolid structure of the medium appears to be advantageous and this can be effected by the use of ¼th per cent agar or 10 per cent gelatin. Of the two, the gelatin is more desirable, and of the latter the most effective material is gelatin from which the impurities have been most thoroughly removed, namely the gelatin employed by Loeb for his isoelectric determinations. This material is best adjusted to the proper hydrogen ion concentration (7.5–7.6) with potassium hydroxide and not with buffer phosphate. Gelatin is the simplest of protein media available and its employment is in keeping with the principle we have found that the requirements for life of the virus of foot-and-mouth disease are of the simplest. The addition of organic or complex protein substances, such as dextrose, broth, serum, lipoids, etc., to a simple basic medium interferes with the effectiveness of the latter. It is thus not surprising that we were unable to confirm the cultural results of Frosch and Dahmen for neither their medium nor its components or their method satisfies the essential conditions necessary to maintain artificially the life of the virus. Furthermore, from the standpoint of technique it was found necessary when comparing 2 or more media for their value in preserving the incitant, to employ all of them in a parallel experiment with the same sample of virus, for the factors of potency of the active agent, contamination, and changes in hydrogen ion concentration, if variable, may give rise to faulty interpretations. Moreover, activity in 3 successive subplants may be regarded as mere preservation but not multiplication of the virus. Finally, we discuss the status of the virus from the point of view of its fluid or particulate, and its animate or inanimate, characters.

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