322 / Biochemistry tissue metabolism

Some aspects of the biochemistry of metabolic processes affecting nutrients appear to have significant consequences for the expected behavior of stable carbon isotopes as tracers of diet. Specifically, we have seen that the simple model of a total scrambling of carbon atoms during endogenous biosynthesis is inconsistent with the expected pathways of some nutrients, whereas other isotopic records in ancient human tissues can be adequately accounted for by this model. 

Whole plasma can also be fractionated into specific lipoprotein size classes to further resolve the underlying biochemistry and metabolism of tissues that deliver these lipids to blood and selectively remove them. Thus, TrueMass analysis can be used to measure the lipid profiles of very-low-density lipoprotein, quantify the lipid pathways responsible for metabolic changes in the liver and measure profiles of high-density lipoprotein to quantify the flux of lipids in reverse cholesterol transport. 

C. J. Kensler2 55 Arthur D. Little, Inc. Sr. Vice President in Charge, Life Sciences Div. Pharmacology, Biochemistry Nutrition cancer tissue metabolism mode of action of carcinogenic agents industrial toxicology... 

The purpose of this book is to present metabolism in an organ-based fashion to make clear the links between biochemistry and physiology. By presenting metabolism in an appropriate tissue-context, the significance of pathways and their inter-relationships should be more meaningful. 

An excellent review of the pharmacological actions of adrenergic neurone blocking agents has been given by Boura and Green [10]. The biochemistry of guanethidine itself has been reviewed by Furst [11], with particular emphasis on tissue distribution and metabolism consequently these two topics are not discussed in detail. 

The use of tissue slices is a standard technique in all aspects of metabolic biochemistry. The tissue is cut into slices, sufficiently thin to allow adequate rates of diffusion in and out of the tissue. The slices are submerged in physiological saline to which substrates or other compounds may be added. 

All of these biological roles of the steroids figure prominently in human well-being. Defects in cholesterol metabolism are major causes of cardiovascular disease. It is no wonder that steroids are a central concern in medical biochemistry. In this chapter we discuss the metabolism of these complex lipids and the plasma lipoproteins in which they and other complex lipids are transported to various tissues. 

Much of my previous research experience had been in lipid biochemistry and DMBA, a polycyclic hydrocarbon, is essentially a lipid xenobiotic. The suggestion had been made by Dao et al O) that the specific induction of mammary tumors by DMBA and other polycyclic hydrocarbons might be due to their tendency, as lipids, to accumulate and persist in the adipose tissue of the mammary gland, thereby increasing the exposure to the susceptible mammary epithelial tissue. If this were indeed a factor in the ability of these compounds to produce mammary tumors, it seemed to us that it might be possible to influence their effectiveness by altering fat metabolism in the body. 

BIOCHEMISTRY metabolism respiration electron transport tissue synthesis CO 2 fixation excretory byproducts... 

The uptake and metabolism of L-glutamate by tissue slices of the cestode Hymenolepis diminuta. Comparative Biochemistry and Physiology, 850. 151-62. 

Elemental analysis of body tissues and fluids by atomic absorption spectrometry with electrothermal atomisation has advanced significantly the understanding of the role of trace elements in clinical biochemistry. All of those aspects of metabolic processes that are affected by changes in the concentrations of accessible trace elements have been studied. These include deficiencies of essential trace elements as a result of inherited or acquired metabolic disorders, or from nutritional inadequacy and excesses of trace elements producing toxicity states as a result of inherited metabolic disorders involving essential trace elements or from the inappropriate exposure to, or ingestion of, non-essential trace elements. 

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