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International Heart Journal 2022
Topics: Humans; Hydrogen-Ion Concentration; Uric Acid
PubMed: 35650143
DOI: 10.1536/ihj.22-127 -
European Annals of Otorhinolaryngology,... May 2023
Topics: Humans; Hyperventilation; Hydrogen-Ion Concentration
PubMed: 36609116
DOI: 10.1016/j.anorl.2022.12.005 -
Journal of Andrology 2002
Topics: Humans; Hydrogen-Ion Concentration; Semen; Urology
PubMed: 12002433
DOI: No ID Found -
Immunology Jul 1958The effects of concentration of hydrogen ion and of neutral salts on the amounts of precipitate and rates of flocculation have been studied with several antigen-antibody...
The effects of concentration of hydrogen ion and of neutral salts on the amounts of precipitate and rates of flocculation have been studied with several antigen-antibody systems, in particular those of bovine serum albumin (BSA) and lysozyme (L) with their rabbit antibodies. In all the systems studied the amount of precipitate and rate of flocculation were maximum over a H range extending on both sides of H 7. The range of H, over which the rate of flocculation was maximum, was narrower than the range over which the amount of precipitate was maximum; outside this range the rate of flocculation fell more steeply than the amount of precipitate. The rate of flocculation, but not the amount of precipitate formed with protein antigens, was reduced in concentrations of sodium chloride above 0.15 N; the reduction was greater in solutions of magnesium chloride and less in solutions of sodium sulphate than in sodium chloride solutions of equivalent concentration. The precipitates formed by protein antigens, that have relatively small molecular weights, with the corresponding antibodies, were more reduced by changes of hydrogen ion concentration than those formed by bovine serum albumin with antibody; the rates of flocculation of these small protein antigens with antibody were also more affected by change of concentration of hydrogen ion and neutral salts. It is suggested that this difference is due to the presence of fewer combining sites on the smaller molecules than on serum albumin. The reduction of the amounts of precipitate, formed by protein antigens, as the hydrogen ion concentration increased, is compatible with the hypothesis that a negatively charged group, with H near 5, on each antibody receptor site is essential for combination with antigen. The reduction of the amount of precipitate through a range of H over which amino groups lose their positive charge suggests that positively charged amino groups are essential for the combination of antigen with antibody; other evidence, however, indicates that positively charged amino groups of the protein antigens are not essential. The effect of increased hydrogen ion concentration on the precipitin curves of Type III pneumococcal polysaccharide with rabbit antibody is consistent with the hypothesis that the presence of negatively charged groups on the combining sites of the antigen are essential for its reactions with antibody. Experiments indicate that when the salt concentration is low it is mainly the later stages of aggregation that are delayed.
Topics: Antibodies; Antigen-Antibody Reactions; Flocculation; Hydrogen-Ion Concentration; Precipitins; Protons; Salts
PubMed: 13574829
DOI: No ID Found -
Canadian Journal of Physiology and... Jun 2021The hydrogen ion concentration ([H]) in intracellular cytoplasmic fluid (ICF) must be maintained in a narrow range in all species for normal protein functions. Thus,...
The hydrogen ion concentration ([H]) in intracellular cytoplasmic fluid (ICF) must be maintained in a narrow range in all species for normal protein functions. Thus, mechanisms regulating ICF are of fundamental biological importance. Studies on the regulation of ICF [H] have been hampered by use of pH notation, failure to consider the roles played by differences in the concentration of strong ions (strong ion difference, SID), the conservation of mass, the principle of electrical neutrality, and that [H] and bicarbonate ions [HCO] are dependent variables. This argument is based on the late Peter Stewart's physical-chemical analysis of [H] regulation reported in this journal nearly forty years ago (Stewart. 1983. Can. J. Physiol. Pharmacol. : 1444-1461. Doi:10.1139/y83-207). We start by outlining the principles of Stewart's analysis and then provide a general understanding of its significance for regulation of ICF [H]. The system may initially appear complex, but it becomes evident that changes in SID dominate regulation of [H]. The primary strong ions are Na, K, and Cl, and a few organic strong anions. The second independent variable, partial pressure of carbon dioxide (PCO), can easily be assessed. The third independent variable, the activity of intracellular weak acids ([A]), is much more complex but largely plays a modifying role. Attention to these principles will potentially provide new insights into ICF pH regulation.
Topics: Bicarbonates; Delusions; Hydrogen-Ion Concentration
PubMed: 33356898
DOI: 10.1139/cjpp-2020-0631 -
Postgraduate Medical Journal Aug 1964
Review
Topics: Adrenal Cortex Hormones; Amino Acids; Biological Transport; DNA; Enzymes; Estrogens; Humans; Hydrogen-Ion Concentration; Metabolism; Permeability; Physiology; Proteins; RNA; Steroids
PubMed: 14179898
DOI: 10.1136/pgmj.40.466.448 -
Journal of Clinical Pathology Sep 1973
Topics: Hydrogen-Ion Concentration; Mathematics
PubMed: 4752417
DOI: 10.1136/jcp.26.9.726-a -
The Journal of Infectious Diseases Feb 2017
Topics: Hydrogen-Ion Concentration; Lysosomes
PubMed: 27974435
DOI: 10.1093/infdis/jiw504 -
Fertility and Sterility 1958
Topics: Animals; Cell Movement; Humans; Hydrogen-Ion Concentration; Male; Osmotic Pressure; Rabbits; Spermatozoa
PubMed: 13619827
DOI: 10.1016/s0015-0282(16)33242-3 -
The Yale Journal of Biology and Medicine Apr 1960
Topics: Hydrogen-Ion Concentration
PubMed: 13849993
DOI: No ID Found