Biochemical And Medical Aspects Of Active Oxygen

The field of "Oxygen Activation" has attracted considerable interest recently, not only because it presents challenges in those fields of basic research that aim to understand the fundamental aspects of chemical and biological reactions that involve dioxygen, but also because of its wide range of practical implications in such diverse fields as medicine, synthesis of pharmaceuticals and other organic compounds, materials science, and atmospheric science. This is the second of two volumes that focus on the subject of oxygen activation, the first slanted toward chemistry and the second toward biological chemistry. We planned these volumes to be more general than many monographs of this sort, not as detailed summaries of the authors' own research but rather as general overviews of the field. Our choice of topics was strongly influenced by our syllabus for a course entitled "Oxygen Chemistry," which two of us have twice taught jointly at UCLA. Definition of important issues, horizons, and future prospects was an important goal, and, although totally comprehensive coverage was not possible, we believe that we have chosen a representative selection of research topics current to the field. We have targeted this work to a diverse audience ranging from professionals in fields from physics to medicine to beginning graduate students who are interested in rapidly acquiring the basics of this field.

Biochemical and Clinical Aspects of Oxygen contains the proceedings of a symposium held on the Pingree Park Campus of Colorado State University on September 24-29, 1978. Contributors discuss the biochemical and clinical aspects of oxygen, focusing on reactions and areas relating to heme, flavin, copper and nonheme iron proteins, organ transplants, carbon monoxide formation and detoxification, oxidant drugs and pollutants, oxygen toxicity, enzyme inactivation, lipid peroxidation, membrane destruction, antioxidants, cataractogenesis, mutagen and carcinogen formation, malaria and trypanosome parasites, and inflammation. This volume is organized into 51 chapters and begins with a discussion of bonding and reactions of dioxygen bound to hemeproteins, along with the pathophysiology of hemolysis due to unstable hemoglobins. The focus then turns to the reactivity and function of leghemoglobin, reduction of oxygen and five redox forms of horseradish peroxidase, and acid-base catalysis and hydrogen bonding in reactions mediated by peroxidases. The reader is methodically introduced to the ligands of cytochrome P-450 and their role in the activation of dioxygen, oxygen and catabolite regulation of hemoprotein biosynthesis in yeast, and factors controlling hemoprotein reactivity. A chapter describing the spectroscopic mapping of oxygen supply and demand in the heart concludes the book. This book will be of interest to biochemists, biophysicists, physicians, toxicologists, immunologists, physiologists, parasitologists, radiologists, and environmentalists.

A NATO Advanced Study Institute on "Oxygen Radicals in Biological Systems: Recent Progress and New Methods of Study" was held in Braga, Portugal between Sep tember 1 and September 14, 1985, in order to consider the basic chemistry and biochem istry of activated oxygen (both radical and non-radical species) and their effect in biolog ical systems. This book summarizes the main lectures given at this meeting. While there is no attempt to cover all the major topics in the expanding subject of oxidative mechanisms in biology, an effort has been made to provide overviews on some key aspects of this field. The authors have attempted to convey a clear picture of both what is known and what remains unclear in their respective subjects. Not only are some of the techniques used for detecting activated oxygen species described, but also their strengths and limi tations. The chemistry of many of these species is discussed and the biological and/or pathological implications are carefully reviewed. The medical and therapeutic aspects of some of the well established pathways of damage and protection are analyzed. It is our hope that the material included in this book might be useful for both researchers and teachers at the graduate level. The success of this meeting was to a large extent due to the tireless committment of Professor Alberto Amaral and Dr. Concei~a:o Rangel; without their outstanding efforts in dealing with all the aspects of the organization, this summer school would not have been possible.

The field of "Oxygen Activation" has attracted considerable interest recently, not only because it presents challenges in those fields of basic research that aim to understand the fundamental aspects of chemical and biological reactions that involve dioxygen, but also because of its wide range of practical implications in such diverse fields as medicine, synthesis of pharmaceuticals and other organic compounds, materials science, and atmospheric science. This is the second of two volumes that focus on the subject of oxygen activation, the first slanted toward chemistry and the second toward biological chemistry. We planned these volumes to be more general than many monographs of this sort, not as detailed summaries of the authors' own research but rather as general overviews of the field. Our choice of topics was strongly influenced by our syllabus for a course entitled "Oxygen Chemistry," which two of us have twice taught jointly at UCLA. Definition of important issues, horizons, and future prospects was an important goal, and, although totally comprehensive coverage was not possible, we believe that we have chosen a representative selection of research topics current to the field. We have targeted this work to a diverse audience ranging from professionals in fields from physics to medicine to beginning graduate students who are interested in rapidly acquiring the basics of this field.

The field of "Oxygen Activation" has attracted considerable interest recently, not only because it presents challenges in those fields of basic research that aim to understand the fundamental aspects of chemical and biological reactions that involve dioxygen, but also because of its wide range of practical implications in such diverse fields as medicine, synthesis of pharmaceuticals and other organic compounds, materials science, and atmospheric science. This is the second of two volumes that focus on the subject of oxygen activation, the first slanted toward chemistry and the second toward biological chemistry. We planned these volumes to be more general than many monographs of this sort, not as detailed summaries of the authors' own research but rather as general overviews of the field. Our choice of topics was strongly influenced by our syllabus for a course entitled "Oxygen Chemistry," which two of us have twice taught jointly at UCLA. Definition of important issues, horizons, and future prospects was an important goal, and, although totally comprehensive coverage was not possible, we believe that we have chosen a representative selection of research topics current to the field. We have targeted this work to a diverse audience ranging from professionals in fields from physics to medicine to beginning graduate students who are interested in rapidly acquiring the basics of this field.

The rapid expansion of the area of free radical biology in the last 25 years has occurred within a framework of assumptions and preconceived notions that has at times directed the course of this movement. The most dominant of these notions has been the view that free radical production is without exception a bad thing, and that the more efficient our elimination of these toxic substances, the better off we will be. The very important observation by Bernard Babior and colleagues in 1973 that activated phagocytes produce superoxide in order to kill micro organisms, served to illustrate that constructive roles are possible for free radicals. For many in the field, however, this merely underscored the deadly nature of oxygen-derived radicals, both from the microbe's point of view and from the host's as well. (Phagocyte-produced superoxide is responsible in part for the tissue injury manifested as inflammation. See Harris and Granger, Chapter 5, and Leff, Hybertson and Repine, Chapter 6.) Mother Nature, however, has a penchant for being able to make a silk purse from a sow's ear. If one is dealt a bad hand, one must simply make the best of it. After two decades of focusing on the destructive side of free radicals, the last few years have begun to reveal a new and finer perspective on free radical metabolism - a role in regulation of cellular function (see Schulze-Osthoff and Baeuerle, Chapter 2). Evidence from a number of sources suggests that an increase in the oxidative status of cell encourages that cell to grow and divide. Increasing the expression of mangnese superoxide dismutase can suppress the malignant phenotype of melanon cells (see Oberley and Oberley, Chapter 3). Oxidative stress beyond a certain poitosis (from the Greek, literally "to fall apart"). Is this suicide response an evolutionary fail-safe device to curtail tumorogenesis? Does oxidative stress-induced apoptosis account for the loss of immune cells in AIDS (see Flores and McCor Chapter 4)? This volume attempts to present the spectrum of roles, both good and bad played by active oxygen species as understood at this point in the evolution of this field of free radical biology.

Taking an interdisciplinary approach, this book and its counterpart, Active Oxygen in Biochemistry, explore the active research area of the chemistry and biochemistry of oxygen. Complementary but independent, the two volumes integrate subject areas including medicine, biology, chemistry, engineering, and environmental studies.