Main description:

Since life was first spawned on earth, all living cells have been engaged in the development of a network of biodefence systems to protect against the deleterious effects of various environmental stress. Besides exposures to so-called pollutants, human beings breathe oxygen and live in a world of unavoidable exposure to endogenous agents such as active oxygens and other free radicals, ionizing radiation, ultraviolet light and chemicals from such natural sources as normal metabolism. To minimize the harmful effects of these exposures, it is necessary to improve our understanding of fundamental life processes that preserve the genome. A new and better understanding of biodefence mechanisms will contribute to practical fields such as risk assessment, identification of high risk groups and individuals, and the prevention and treatment of genetic diseases such as cancer caused by environmental stress. Besides direct effects on DNA, active oxygens and free radicals are believed to cause functional defects in living organisms by affecting signal transduction associated with the activation of specific genes, which can in tum lead to cancer and premature aging.

Contents:

I Protection against Oxidative Stress-induced Damages.- 1. Histidine-containing Peptides and Hydroquinone Derivatives as Synthetic Antioxidants.- 2. In Vivo ESR Measurement of Free Radical Reactions in Living Mice.- 3. Biodefence against Active Oxygens and Free Radicals Induced by Oxidative Stress.- 4. ? -Lipoic Acid: A Metabolic Antioxidant and Redox Modulator of Signal Transduction.- II Stress-induced Signal Transduction Systems for Biodefence.- 5. Regulatory Mechanisms of Gene Activation Induced by DNA Damage.- 6. Mechanisms of Immediate-early Phase of X-ray-induced Expression of IL-1? Gene in Normal Myeloid Cells.- III Apoptosis as a Biodefence Mechanism.- 7. An Overview of Apoptosis with Emphasis on Its Biodefence Functions.- 8. Radiation-induced Apoptosis in Rat Thymocytes.- 9. DNA Fragmentation during Apoptosis Is Catalyzed by DNase ?.- 10. Biodefence Mechanisms against Radiation-induced Apoptosis.- IV Radiation-induced DNA Damages, Repair and Mutagenesis.- 11. Repair of Ionizing Radiation Induced Base Damage: Role of DNA Glycosylases.- 12. cDNA Catalog of Fission Yeast (Schizosaccharomyces pombe) and Its Application for Cloning of Mammalian DNA Repair Gene.- 13. DNA Double Strand Break Repair: A Comparison between Mammalian and Yeast Cells.- 14. Genome Analysis of the AT Region of Human Chromosome 11 and Identification of a New Gene, NPAT, Physically Linked to the ATM Gene.- 15. Radioadaptation of Mutation in Human x Hamster Hybrid AL Cells.- 16. Mutation as a (Bio)Chemical Process (1958-1996).- V Repair of UV-induced DNA Damages.- 17. Functional Studies of the XPA Gene for Nucleotide Excision Repair and Ultraviolet Radiation-induced Skin Carcinogenesis.- 18. Characterization of xpg-deficient Mice.- 19. Transcription-coupled Repair as a Biodefence Mechanism.