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A S Beedle

Publications and source records attributed to A S Beedle.

8 recordsLinked to original sources
PubMed1999

A philosopher looks at neuroscience.

The last two centuries, and the last fifty years in particular, have seen a dramatic increase in our understanding of the brain. More recently, philosophers have rekindled the debate about the nature of the mind and have begun to ask how and to what extent the features of the conscious mind, of the self, can be described in solely neurobiological terms. This essay describes a few ways in which neuroscientific research has changed the way philosophers think about the mind and also suggests some ways in which the methods and questions of philosophers might affect neuroscience.

Humans↗
PubMed1974

Some properties and a suggested reclassification of mevaldate reductase.

Mevaldate reductase was purified 70-fold from rat liver. The partly purified enzyme had a molecular weight of 27000-30000, reduced certain aromatic aldehydes and was inhibited by barbiturates. These properties are similar to those of other animal tissue aldehyde reductases (EC 1.1.1.2) and it is suggested that mevaldate reductase be reclassified as one of this group.

Alcohol Oxidoreductases↗
PubMed1974

Studies on the biosynthesis of tetrahymanol in Tetrahymena pyriformis. The mechanism of inhibition by cholesterol.

Tetrahymanol biosynthesis by the protozoan Tetrahymena pyriformis was progressively inhibited by the inclusion of cholesterol in the growth medium. Studies with labelled precursors of tetrahymanol have established that there are two major sites of inhibition in whole cells. The inhibition at the first site, between acetate and mevalonate, occurred rapidly after addition of cholesterol. The activity of 3-hydroxy-3-methylglutaryl-CoA reductase (EC 1.1.1.34), a predominantly cytosolic enzyme in this organism, was not inhibited in cholesterol-grown cells nor by addition of cholesterol directly to the assay medium. The second major site of inhibition in whole cells is between mevalonate and squalene and this is accompanied by inhibition of the enzyme that converts farnesyl-pyrophosphate into squalene (squalene synthetase). Squalene cyclase is partially inhibited. The conversion of mevalonate into tetrahymanol in vitro was not inhibited by the addition of cholesterol to the assay medium. Tetrahymanol added to the culture medium is taken up by the cells but does not inhibit endogenous biosynthesis. It is suggested that cholesterol inhibits the later stages of tetrahymanol biosynthesis by causing a change in membrane structure and function which alters the activity of membrane-bound enzymes.

Acetates↗