Cancer has developed into one of the most complex of biological problems and research into its causes, development, manifestations and control is the focal point of a large number of scientific disciplines. It is unlikely that any investigator can completely confine his work or interest within the boundaries of only one of its component disciplines. Cowdry, in a discussion on modern trends in cancer research, has remarked "it is said that in cancer the most productive research is between the sciences, as in the cell itself very fundamental processes take place at the surfaces between different materials". [...]

The experiments to be presented consist of an attempt to extend the observations of Dickens and Greville on the effects of anoxia and lack of substrate on the subsequent carbohydrate metabolism of brain tissue. Dickens and Greville (1933) working with brain slices, and Elliott and Henry (1946) with suspensions, showed that deprivation of both oxygen and substrate for relatively short periods caused a marked inhibition of the subsequent anaerobic glycolysis, while respiration was inhibited to a lesser degree.

The work to be presented in this thesis concerns the divergent pathways of tryptophan metabolism to the 5-hydroxyindoles and to kynurenine. More specifically an attempt has been made to elucidate the role of dietary tryptophan in the operation of these two pathways. Previous investigators have implied that thiamine is involved in the kynurenine-forming pathway. Both nutritional studies and experiments in vitro were carried out to determine just where thiamine (or thiamine pyrophosphate, its coenzyme form) exerts its action.

The nitrification of ammonia and nitrite in soil is but one part of the overall nitrogen cycle. Essentially, nitrification may be defined as an oxidative-reductive mechanism whereby ammonium ions or nitrite ions are oxidized to nitrate by microorganisms.

At the outbreak of World War II, work was initiated in the Department of Biochemistry at McGill University, under the direction of Dr. O. F. Denstedt, on a study of the means whereby the then existing methods of blood preservation might be improved. Similar investigations were undertaken in many other laboratories throughout the world, particularly in the United States and Great Britain. The availability of blood and plasma for prompt treatment of the wounded at the fighting front accounted for the tremendous saving of lives in World War II as compared with World War I.

The literature on the enzyme tyrosinase is extensive and to a large extent contradictory. No attempt will be made to give a complete coverage of the publications on this subject. Because of the confusion in the nomenclature and classification of the various enzymes that oxidize phenols, as to properties and function, it is expedient to confine the survey to the relevant details. [...]

A quarter of a century has elapsed since the first steroid hormone was isolated. Since then, there has been a profound and significant advance in our knowledge of the biogenesis of these steroid hormones and their ultimate fate in the living organism. Less progress, however, has been made in understanding the mode of their physiological action. Studies during the last decade have pointed to a more or less common pathway of steroid biogenesis and metabolism.

There have been remarkable developments in the field of the intermediary metabolism of carbohydrates during the past twenty five years. These developments were due (1) the elucidation of the anaerobic glycolytic breakdown of carbohydrate having its origin in Embden's discovery of phosphoglyceric acid in 1933 and (2) the oxidative tricarboxylic acid cycle discovered by Krebs and Johnson in 1937.The present concepts of the metabolism or carbohydrates centres round these two themes. However, the central role of these pathways is being challenged by the discovery and elucidation of alternative pathways of metabolism.

Ten years ago, the glycolytic system as elucidated by Embden, Meyerhof and others, along with the tricarboxylic acid system as elucidated by Krebs and others, was believed to be the sole pathway of carbohydrate metabolism. Other reactions, known to be concerned with the metabolism of carbohydrates, were considered to be side reactions of the major scheme. [...]

The work of Bourchadat and Sandras (1) was the first recorded attempt to determine the fate of ethanol in the body. They suggested that ethanol is completely burned in the organism to carbon dioxide. Although this observation was confirmed by others, the general belief persisted that ethanol was not oxidised at all, but was eliminated unchanged (2). This theory was based on the results of the animal experiments formed about 1870 which showed that ethanol appeared both in the urine and expired air. Later, Dupre, Anstie and others (3,4,5,6) found that most of the administered ethanol disappears and that the amounts recovered in the urine represent only a very small fraction of the original dose.