Effects of pH and of various concentrations of sodium, potassium, and calcium chloride on motility of the isolated crop of Periplaneta americana

1941 ◽  
Author(s):  
James Thompson Griffiths
Keyword(s):  
Calcium Chloride ◽  
Periplaneta Americana ◽  
Sodium Potassium ◽  
Effects Of Ph

Optimizing Adjuvants to Overcome Glyphosate Antagonistic Salts

1993 ◽  
Vol 7 (2) ◽  
pp. 337-342 ◽  
Author(s):  
John D. Nalewaja ◽  
Robert Matysiak
Keyword(s):  
Sodium Bicarbonate ◽  
Calcium Chloride ◽  
Sodium Potassium ◽  
Greenhouse Experiments ◽  
Calcium And Magnesium ◽  
Diammonium Sulfate

Glyphosate toxicity to wheat was antagonized more by calcium chloride than sodium bicarbonate. Mixtures of the salts at greater than 100 mg L−1sodium bicarbonate and 200 mg L−1calcium chloride were additive in antagonism of glyphosate in the greenhouse experiments. Surfactant and oil adjuvants did not overcome sodium bicarbonate or calcium chloride antagonism of glyphosate. Oil adjuvants were generally antagonistic to glyphosate. An equation is presented that determines the amount of diammonium sulfate required to overcome glyphosate antagonism based upon the sodium, potassium, calcium, and magnesium cations in the spray carrier.

Effect of Certain Cations on Relaxation of the Glycerol-Extracted Heart Muscle of Frogs

1956 ◽  
Vol 186 (2) ◽  
pp. 304-308 ◽  
Author(s):  
Lee W. Hawkins ◽  
John R. Smith
Keyword(s):  
Calcium Chloride ◽  
Heart Muscle ◽  
Room Temperature ◽  
Rapid Rate ◽  
Ventricular Contraction ◽  
Sodium Potassium ◽  
Ringer’S Solution ◽  
Contraction And Relaxation

Hearts of large bullfrogs ( Rana catesbiana) were extracted in 50% glycerol at –10 to –20°C. These hearts were then perfused with solutions of desired molarity, and contractions were measured by a compound lever attached to the ventricles. Perfusion was carried out with solutions containing magnesium, sodium, potassium or calcium chloride (using the molarities of these ions in Ringer's solution); the solutions were adjusted to ph 7.5 at room temperature. The salts were perfused singly or in various combinations. Ventricular contraction was induced by ATP (0.016 m, adjusted to ph 7.5) added directly to the perfusate. The data indicate that, following contraction of the hearts with ATP, the perfusion of Na, Mg and K cations enhance relaxation of the glycerinated hearts. Of these cations, the Na ion may be of particular importance in relaxation of the ATP-contracted muscle, for Na perfused alone caused a more rapid rate of muscle elongation. However, when the hearts were previously irrigated with Mg ion, perfusion with Na then provoked strikingly rapid relaxation of the glycerinated hearts. Ca ion was not observed to recontract the hearts after original ATP-contraction and relaxation by Na-Mg irrigation.

scholarly journals Effects of pH, Calcium Chloride, and Chymosin Concentration on Coagulation Properties of Abnormal and Normal Milk

1985 ◽  
Vol 68 (10) ◽  
pp. 2527-2533 ◽  
Author(s):  
L.M. Okigbo ◽  
G.H. Richardson ◽  
R.J. Brown ◽  
C.A. Ernstrom
Keyword(s):  
Calcium Chloride ◽  
Effects Of Ph

scholarly journals EFFECTS OF pH AND OF VARIOUS CONCENTRATIONS OF SODIUM, POTASSIUM, AND CALCIUM CHLORIDE ON MUSCULAR ACTIVITY OF THE ISOLATED CROP OF PERIPLANETA AMERICANA (ORTHOPTERA)

1943 ◽  
Vol 26 (6) ◽  
pp. 541-558 ◽  
Author(s):  
James T. Griffiths ◽  
Oscar E. Tauber
Keyword(s):  
Periplaneta Americana ◽  
Ph Value ◽  
Muscular Activity ◽  
Physiological Salt Solution ◽  
Activity Product ◽  
Hydroxyl Ion ◽  
Significant Difference ◽  
Effects Of Ph ◽  
Average Activity ◽  
Increased Activity

1. Twenty-five solutions which contained KCl (0.0, 0.2, 0.4, 0.6, and 0.8 gm. per liter), in combination with CaCl2 (0.0, 0.2, 0.4, 0.6, and 0.8 gm. per liter), 10.0 gm. of NaCl, and 0.2 gm. of NaHCO3 per liter of solution were tested in order to determine satisfactory KCl/CaCl2 ratios in an insect physiological salt mixture for the maintenance of muscular activity by the isolated crop of the American roach. Satisfactory activity products (0.390 to 0.549) were obtained in seven mixtures with KCl/CaCl2 ratios of 0.2/0.2, 0.4/0.4, 0.6/0.6, 0.8/0.8, 0.2/0.4, 0.4/0.6, and 0.6/0.8, expressed as gram per liter. These ratios lie between 0.50 and 1.00. In solutions which contained calcium, but no potassium, approximately 50 per cent of the crops exhibited an initial tone increase and were arrested in rigor. See Fig. 2. In solutions which contained potassium, but no calcium, all crops showed an initial loss of tone and arrest in relaxation. See Fig. 2. 2. Seven KCl/CaCl2 ratios (see paragraph 1 above) were tested with eight NaCl concentrations (1.0, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, and 1.8 per cent) at a pH of 8.0. In these mixtures, the ones with KCl/CaCl2 ratios of less than 1.0 produced higher activity products than those with ratios equal to 1.00. The highest average activity product (0.849) was obtained in the solutions with 0.2 gm. of KCl and 0.4 gm. of CaCl2 per liter. 3. Four KCl/CaCl2 ratios (0.2/0.2, 0.4/0.4, 0.2/0.4, and 0.4/0.6 gm. per liter) were tested with 1.4, 1.5, and 1.6 per cent NaCl at a pH of 7.5. When analyzed with data from comparable solutions at a pH of 8.0, it was found that 1.4 per cent NaCl afforded an optimum environment for isolated crop activity. 4. Effects of hydrogen and hydroxyl ion concentrations were studied at pH values of 6.8, 7.5, 8.0, and 8.9. The highest average activity product, 1.011, was produced at a pH of about 8.0. 5. A satisfactory physiological salt solution for the isolated foregut of the American roach, Periplaneta americana, would contain 14.0 gm. of NaCl, 0.4 gm. of CaCl2, 0.2 gm. of KCl, and 0.2 gm. of NaHCO3 per liter of solution. This mixture should have a pH value between 7.8 and 8.2. 6. Durations of crop activity extending over periods as long as 25 hours were quite common, and several crops maintained contractions for more than 30 hours. The greatest longevity was for crop 814, from a female, which continued activity for slightly more than 47 hours. 7. A significant difference between the activity products of the crops from males and the crops from females was recorded. Although there was not a significant difference in the amount of food ingested by males and females, 12 hours after feeding there was more food in the females' crops, and the food progressed more rapidly through the males' crops than through the females'. In addition, crops from the two sexes reacted differently to the effects of day old solutions. This sex difference is apparently related to an inherently increased activity of the crop from the male roach.

Effects of pH on the heart of the American cockroach,Periplaneta Americana Linnaeus

1957 ◽  
Vol 49 (3) ◽  
pp. 503-508 ◽  
Author(s):  
Daniel Ludwig ◽  
Edwin R. Tefft ◽  
Sister Mary Danutha Suchyta
Keyword(s):  
Periplaneta Americana ◽  
American Cockroach ◽  
Effects Of Ph

Effect of pH and inhibitors on beta-amyloid fibril assembly

1996 ◽  
Vol 54 ◽  
pp. 752-753
Author(s):  
Beverly E. Maleeff ◽  
Timothy K. Hart ◽  
Stephen J. Wood ◽  
Ronald Wetzel
Keyword(s):  
Amyloid Fibril ◽  
Peptide Fragment ◽  
Hydrophobic Peptides ◽  
Amyloid Fibril Formation ◽  
Effects Of Ph ◽  
Severity Of The Disease ◽  
Kinetics Of ◽  
The Brain

Alzheimer's disease is characterized post-mortem in part by abnormal extracellular neuritic plaques found in brain tissue. There appears to be a correlation between the severity of Alzheimer's dementia in vivo and the number of plaques found in particular areas of the brain. These plaques are known to be the deposition sites of fibrils of the protein β-amyloid. It is thought that if the assembly of these plaques could be inhibited, the severity of the disease would be decreased. The peptide fragment Aβ, a precursor of the p-amyloid protein, has a 40 amino acid sequence, and has been shown to be toxic to neuronal cells in culture after an aging process of several days. This toxicity corresponds to the kinetics of in vitro amyloid fibril formation. In this study, we report the biochemical and ultrastructural effects of pH and the inhibitory agent hexadecyl-N-methylpiperidinium (HMP) bromide, one of a class of ionic micellar detergents known to be capable of solubilizing hydrophobic peptides, on the in vitro assembly of the peptide fragment Aβ.

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