Theoretical Analysis of Interactions between Potassium Ions and Organic Electrolyte Solvents: A Comparison with Lithium, Sodium, and Magnesium Ions

2016 ◽  
Vol 164 (2) ◽  
pp. A54-A60 ◽  
Author(s):  
Masaki Okoshi ◽  
Yuki Yamada ◽  
Shinichi Komaba ◽  
Atsuo Yamada ◽  
Hiromi Nakai
Keyword(s):  
Theoretical Analysis ◽  
Organic Electrolyte ◽  
Potassium Ions ◽  
Magnesium Ions

EFFECTS OF CATIONS ON SUGAR ABSORPTION BY ISOLATED SURVIVING GUINEA PIG INTESTINE

1958 ◽  
Vol 36 (3) ◽  
pp. 347-362 ◽  
Author(s):  
E. Riklis ◽  
J. H. Quastel
Keyword(s):  
Guinea Pig ◽  
Glucose Transport ◽  
Active Transport ◽  
Glucose Absorption ◽  
Ion Concentration ◽  
Potassium Ions ◽  
Magnesium Ions ◽  
Sugar Absorption ◽  
Rate Of Absorption ◽  
High Concentrations

The rate of absorption of glucose from isolated surviving guinea pig intestine increases with increase of the concentration of glucose in the lumen until a maximum rate is obtained. The relation between absorption rate of glucose and initial glucose concentration conforms to an equation of the Michaelis–Menten type. The apparent Km(half saturation concentration) is 7 × 10−3M. Increase of the concentration of potassium ions in the Ringer–bicarbonate solution bathing the intestine leads to an increase of the rate of glucose absorption, this being most marked with 15.6 meq./liter K+and 14 mM glucose. No such stimulating action of potassium ions is observed on glucose absorption under anaerobic conditions. The effect of increased potassium ion concentration is to accelerate the rate of transport found with low concentrations of glucose to the maximum value found with high concentrations of the sugar. Sodium ions must be present for glucose absorption to take place and omission of magnesium ions from a Ringer–bicarbonate solution, containing 15.6 meq./liter K+, brings about a decreased rate of active glucose transport. Magnesium ions are necessary for the stimulated rate of glucose absorption obtained in the presence of potassium ions. The presence of ammonium ions decreases the rate of glucose absorption. Potassium ions may be effectively replaced by rubidium ions for stimulation of glucose transport. Cesium ions do not activate. The proportion of glucose to fructose appearing in the serosal solution, when fructose is absorbed from the mucosal solution, depends on the concentration of fructose present. The proportion may be as high as 9:1 with low (7 mM) fructose concentrations; it decreases with increasing fructose concentrations. The active transport of fructose, as demonstrated by the conversion of fructose in the isolated surviving guinea pig intestine, is enhanced by the presence of potassium ions (15.6 meq./liter). The rate of transport of fructose itself is unaffected by potassium. Using radioactive glucose and fructose, it is shown that the total amount of sugar transferred through the intestine as estimated by the radioactivity appearing in the serosal solution is approximately that calculated from chemical analyses. Potassium ions have no activating action on the transport of sugars such as sorbose, mannose, and D-glucosamine, but have a marked effect on galactose transport. The results support the conclusion that potassium ions do not influence active transport of glucose, fructose, and galactose by a change of intestinal permeability to these sugars, but do so by affecting a specific phase involved in the mechanism of active transport of sugars. The presence of L-glutamine stimulates active transport of glucose, whereas that of L-glutamate tends to diminish it.

Synthesis of new exenatide analogs and investigation of their influence on glycemia and renal function in rats

2011 ◽  
Vol 57 (3) ◽  
pp. 42-47
Author(s):  
A E Bogolepova ◽  
A V Kutina ◽  
A S Marina ◽  
S K Nikol'skaia ◽  
E I Shakhmatova ◽  
...  
Keyword(s):  
Renal Excretion ◽  
Free Water ◽  
Potassium Ions ◽  
Magnesium Ions ◽  
Glucose Loading ◽  
Rat Models ◽  
Renal Functions ◽  
In Vivo Testing ◽  
Physiologically Active Compounds

New analogs of exenatide with amino acid substitutions at 14, 35, and 39 have been synthesized. They were shown to be more stable than original exenatide in aqueous solutions. In vivo testing on rat models of glucose loading showed that exenatide and its novel analogs possess hypoglycemic activity and stimulate renal excretion of sodium and magnesium ions and osmotically free water but have virtually no effect on the elimination of potassium ions. Experiments with isolated skin and urinary bladder preparations from male frogs showed that exenatide and its analogs promote biosynthesis of physiologically active compounds modulating renal functions.

scholarly journals Aggregation dynamics of charged peptides in water: effect of salt concentration

2019 ◽  
Author(s):  
Susmita Ghosh ◽  
T Devanand ◽  
Upayan Baul ◽  
Satyavani Vemparala
Keyword(s):  
Early Stage ◽  
Potassium Ions ◽  
Sodium Ions ◽  
Magnesium Ions ◽  
Compact Structure ◽  
Biologically Relevant ◽  
Kinetics And Dynamics ◽  
Aggregate Morphology ◽  
Dynamics Simulations ◽  
Charged Peptides

Extensive molecular dynamics simulations have been employed to probe the effects of salts on the kinetics and dynamics of early-stage aggregated structures of steric zipper peptides in water. The simulations reveal that the chemical identity and valency of cation in the salt play a crucial roles in aggregate morphology of the peptides. Sodium ions induce the most aggregated structures but this is not replicated by potassium ions which are also monovalent. Divalent Magnesium ions induce aggregation, but to a lesser extent than that of sodium and their interactions with the charged peptides are also significantly different. The aggregate morphology in the presence of monovalent sodium ions is a compact structure with interpenetrating peptides, which differs from the more loosely connected peptides in the presence of either potassium or magnesium ions. The different ways in which the cations effectively renormalize the charges of peptides is suggested to be the cause of the differential effects of different salts studied here. These simulations underscore the importance of understanding both the valency and nature of of salts in biologically relevant aggregated structures.

Theoretical Analysis of the Oxidation Potentials of Organic Electrolyte Solvents

2015 ◽  
Vol 4 (9) ◽  
pp. A103-A105 ◽  
Author(s):  
M. Okoshi ◽  
A. Ishikawa ◽  
Y. Kawamura ◽  
H. Nakai
Keyword(s):  
Theoretical Analysis ◽  
Organic Electrolyte ◽  
Oxidation Potentials

EFFECTS OF CATIONS ON SUGAR ABSORPTION BY ISOLATED SURVIVING GUINEA PIG INTESTINE

1958 ◽  
Vol 36 (1) ◽  
pp. 347-362 ◽  
Author(s):  
E. Riklis ◽  
J. H. Quastel
Keyword(s):  
Guinea Pig ◽  
Glucose Transport ◽  
Active Transport ◽  
Glucose Absorption ◽  
Ion Concentration ◽  
Potassium Ions ◽  
Magnesium Ions ◽  
Sugar Absorption ◽  
Rate Of Absorption ◽  
High Concentrations

The rate of absorption of glucose from isolated surviving guinea pig intestine increases with increase of the concentration of glucose in the lumen until a maximum rate is obtained. The relation between absorption rate of glucose and initial glucose concentration conforms to an equation of the Michaelis–Menten type. The apparent Km(half saturation concentration) is 7 × 10−3M. Increase of the concentration of potassium ions in the Ringer–bicarbonate solution bathing the intestine leads to an increase of the rate of glucose absorption, this being most marked with 15.6 meq./liter K+and 14 mM glucose. No such stimulating action of potassium ions is observed on glucose absorption under anaerobic conditions. The effect of increased potassium ion concentration is to accelerate the rate of transport found with low concentrations of glucose to the maximum value found with high concentrations of the sugar. Sodium ions must be present for glucose absorption to take place and omission of magnesium ions from a Ringer–bicarbonate solution, containing 15.6 meq./liter K+, brings about a decreased rate of active glucose transport. Magnesium ions are necessary for the stimulated rate of glucose absorption obtained in the presence of potassium ions. The presence of ammonium ions decreases the rate of glucose absorption. Potassium ions may be effectively replaced by rubidium ions for stimulation of glucose transport. Cesium ions do not activate. The proportion of glucose to fructose appearing in the serosal solution, when fructose is absorbed from the mucosal solution, depends on the concentration of fructose present. The proportion may be as high as 9:1 with low (7 mM) fructose concentrations; it decreases with increasing fructose concentrations. The active transport of fructose, as demonstrated by the conversion of fructose in the isolated surviving guinea pig intestine, is enhanced by the presence of potassium ions (15.6 meq./liter). The rate of transport of fructose itself is unaffected by potassium. Using radioactive glucose and fructose, it is shown that the total amount of sugar transferred through the intestine as estimated by the radioactivity appearing in the serosal solution is approximately that calculated from chemical analyses. Potassium ions have no activating action on the transport of sugars such as sorbose, mannose, and D-glucosamine, but have a marked effect on galactose transport. The results support the conclusion that potassium ions do not influence active transport of glucose, fructose, and galactose by a change of intestinal permeability to these sugars, but do so by affecting a specific phase involved in the mechanism of active transport of sugars. The presence of L-glutamine stimulates active transport of glucose, whereas that of L-glutamate tends to diminish it.

The Synthesis and Physico-chemical Characterization of Anthocyan-magnesium Compound

2008 ◽  
Vol 59 (7) ◽  
Author(s):  
Cerasela Elena Gird ◽  
Ligia Elena Dutu ◽  
Teodora Dalila Balaci ◽  
Veronica Naceas
Keyword(s):  
Chemical Characterization ◽  
Potassium Ions ◽  
Magnesium Ions ◽  
Ribes Nigrum ◽  
Black Currant ◽  
Physico Chemical ◽  
Vis Spectroscopy ◽  
Therapeutic Properties ◽  
Magnesium Compound

This paper presents the results of the studies regarding the obtaining and the physico- chemical characterization of the semi-synthesis compound called anthocyan-magnesium. The coupling of the anthocyans extracted from Ribes nigrum L. (black currant) with magnesium had the purpose to sum the therapeutic properties of the two components. The anthocyanic extract contains up to 22.4 � 24.0% anthocyans (expressed in cyanidin chloride). The anthocyan-magnesium compound contains 13.37 � 15.25% anthocyans, 11.23 � 11.29% magnesium ions (14 mEg) and 1.56 � 1.96% potassium ions. Spectral methods (IR and UV-VIS spectroscopy) and magnetic determinations confirm the structure of the semisynthetic compound. The coupling of the anthocyans extracted from Ribes nigrum L. (black currant) with magnesium had the purpose to sum the therapeutic properties of the two components. The anthocyanic extract contains up to 22.4 � 24.0% anthocyans (expressed in cyanidin chloride). The anthocyan-magnesium compound contains 13.37 � 15.25% anthocyans, 11.23 � 11.29% magnesium ions (14 mEg) and 1.56 � 1.96% potassium ions. Spectral methods (IR and UV-VIS spectroscopy) and magnetic determinations confirm the structure of the semisynthetic compound.

Theoretical Analysis on De-Solvation of Lithium, Sodium, and Magnesium Cations to Organic Electrolyte Solvents

2013 ◽  
Vol 160 (11) ◽  
pp. A2160-A2165 ◽  
Author(s):  
Masaki Okoshi ◽  
Yuki Yamada ◽  
Atsuo Yamada ◽  
Hiromi Nakai
Keyword(s):  
Theoretical Analysis ◽  
Organic Electrolyte

scholarly journals CHEMICAL ANTAGONISM OF IONS

1928 ◽  
Vol 12 (2) ◽  
pp. 241-258 ◽  
Author(s):  
Henry S. Simms
Keyword(s):  
Ionic Strength ◽  
Oxalic Acid ◽  
Quantitative Data ◽  
Marked Decrease ◽  
Short Chain ◽  
Potassium Ions ◽  
Sodium Ions ◽  
Magnesium Ions ◽  
Biological Interest ◽  
Wide Range

Magnesium ions decrease the activity of divalent organic anions much more than the normal decrease produced by sodium ions. The effect is very large with short chain acids, particularly oxalic acid. The addition of sodium or potassium ions produces a marked decrease in the effect of magnesium diions on the activity of oxalate diions. Quantitative data on 0.005 molar solutions of oxalic diion over a wide range of concentrations of MgCl2 and of NaCl (or KCl) show that the following equation is obeyed: See PDF for Equation where A is an empirical value dependent on the concentration of oxalate diion (0x=). This equation has been shown to hold down to zero ionic strength of Na+ and K+, and hence to be valid in the physiological range. These observations are of biological interest since the activity of proteins should (like oxalic acid) show a similar antagonism.

Microdiffraction Patterns of Small Metallic Particles II; Theoretical Analysis

1982 ◽  
Vol 40 ◽  
pp. 668-669
Author(s):  
A. Gómez ◽  
P. Schabes-Retchkiman ◽  
M. José-Yacamán ◽  
T. Ocaña
Keyword(s):  
Experimental Data ◽  
Electron Diffraction ◽  
Theoretical Analysis ◽  
Size Range ◽  
Dynamical Theory ◽  
Metallic Particles ◽  
Splitting Effect

The splitting effect that is observed in microdiffraction pat-terns of small metallic particles in the size range 50-500 Å can be understood using the dynamical theory of electron diffraction for the case of a crystal containing a finite wedge. For the experimental data we refer to part I of this work in these proceedings.

Observations of the Thermal Decomposition of Brucite

1968 ◽  
Vol 26 ◽  
pp. 446-447
Author(s):  
P. L. Burnett ◽  
W. R. Mitchell ◽  
C. L. Houck
Keyword(s):  
Thermal Decomposition ◽  
Magnesium Oxide ◽  
Basal Plane ◽  
Magnesium Ions ◽  
A Value ◽  
Reaction Proceeds

Natural Brucite (Mg(OH)2) decomposes on heating to form magnesium oxide (MgO) having its cubic ﹛110﹜ and ﹛111﹜ planes respectively parallel to the prism and basal planes of the hexagonal brucite lattice. Although the crystal-lographic relation between the parent brucite crystal and the resulting mag-nesium oxide crystallites is well known, the exact mechanism by which the reaction proceeds is still a matter of controversy. Goodman described the decomposition as an initial shrinkage in the brucite basal plane allowing magnesium ions to shift their original sites to the required magnesium oxide positions followed by a collapse of the planes along the original <0001> direction of the brucite crystal. He noted that the (110) diffraction spots of brucite immediately shifted to the positions required for the (220) reflections of magnesium oxide. Gordon observed separate diffraction spots for the (110) brucite and (220) magnesium oxide planes. The positions of the (110) and (100) brucite never changed but only diminished in intensity while the (220) planes of magnesium shifted from a value larger than the listed ASTM d spacing to the predicted value as the decomposition progressed.

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