Journal ArticleDOI
Relation between Low Erythrocyte Acetylcholinesterase Activity and Membrane Lipids in Paroxysmal Noctural Haemoglobinuria
TLDR
The results and that from comparison of activation of deoxycholate‐extracted enzyme by lipids from normal erythrocytes suggest that the low acetylcholinesterase activity in PNH ery Throcytes is due, at least in part, to alteration in the lipid environment of the enzyme.Abstract:
Summary. Acetylcholinesterase of intact erythrocytes, their ghosts and salt soluble extracts obtained from patients with paroxysmal nocturnal haemoglobinuria (PNH) does not differ from normal with respect to Km values for acetylthiocholine, and Ki values for phenyltrimethylammonium iodide. However, the enzyme from PNH sources has lower Vmax values than normal, has different thermal stability from normal, has less distinctive transition temperature in the Arrhenius plots, and is less subject to inhibition by stearic acid. These results and that from comparison of activation of deoxycholate-extracted enzyme by lipids from normal erythrocytes suggest that the low acetylcholinesterase activity in PNH erythrocytes is due, at least in part, to alteration in the lipid environment of the enzyme.read more
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Free Radical Reactions in Medicine
TL;DR: The chemistry of Free Radical Reactions and its role in the Pathogenesis of Various Human Diseases, and the role of Free Radicals in Carcinogenesis: Connection Between Atherosclerosis, Ageing, Carcinogenic and Mutagenesis.
Journal ArticleDOI
Paroxysmal nocturnal haemoglobinuria.
TL;DR: The analysis of the abnormality of the membrane in paroxysmal nocturnal haemoglobinuria is an exercise in complexity complexified as mentioned in this paper, and it is little wonder that a disease which is uncommon but not rare continues to fascinate investigators from a wide variety of disciplines.
Journal ArticleDOI
The acetylcholinesterase defect in paroxysmal nocturnal hemoglobinuria: evidence that the enzyme is absent from the cell membrane
TL;DR: It is suggested that abnormal PNH erythrocytes lack AchE enzyme activity due to the absence of the AchE molecule from the cell membrane.
Journal ArticleDOI
Increased enzymatic activity of the alternative pathway convertase when bound to the erythrocytes of paroxysmal nocturnal hemoglobinuria.
TL;DR: This is the first instance in which the enzyme activity of a complement complex has been shown to be increased by being affixed to an abnormal surface.
Journal ArticleDOI
The erythrocyte membrane in essential hypertension characterization of the temperature dependence of lithium efflux
Rachel Levy,Avinoam Livne +1 more
TL;DR: It is concluded that the unique temperature dependence of Li efflux in erythrocytes of hypertensives results from a localized modification in the membrane, and the expression of the temperature dependence as judged by the sharp transition in slope, apparently reflects the cooperative involvement of membrane lipids, associated with theLi efflux system.
References
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Journal Article
Protein Measurement with the Folin Phenol Reagent
TL;DR: Procedures are described for measuring protein in solution or after precipitation with acids or other agents, and for the determination of as little as 0.2 gamma of protein.
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A rapid method of total lipid extraction and purification.
E. G. Bligh,W. J. Dyer +1 more
TL;DR: The lipid decomposition studies in frozen fish have led to the development of a simple and rapid method for the extraction and purification of lipids from biological materials that has been applied to fish muscle and may easily be adapted to use with other tissues.
Journal ArticleDOI
A new and rapid colorimetric determination of acetylcholinesterase activity.
TL;DR: A photometric method for determining acetylcholinesterase activity of tissue extracts, homogenates, cell suspensions, etc., has been described and Kinetic constants determined by this system for erythrocyte eholinesterases are presented.