Carcinogenesis by Ultraviolet Light 9781400879922

Table of contents :
Contents
Preface
Part I. Introductory
1. Introduction to the Problem
2. "Ultraviolet Light": A Problem in Definition
Mode of Action of Light
What Is Meant by "Ultraviolet Light"?
3. Absorption of Ultraviolet Light
Absorption and Penetration in Living Systems
Action Spectra and Absorption Spectra
Sources of Ultraviolet Light
Photochemical Consequences of Absorption
Part II. Some Effects of Ultraviolet Light on Biological Systems
4. Inactivation and Lethal Action
Inactivation of Enzymes
Inactivation of Viruses
Lethal Effects on Microorganisms
Relation to Other Effects
5. Hemolysis: Cytolysis: Lysogeny
Hemolysis
Cytolysis and Permeability Changes in Complex Cells
Lysogeny in Bacteria
6. Comparison with Effects of Other Types of Radiation
Photosensitized Oxidation (Photodynamic Action
Effects of Ionizing Radiations
O2-Dependence in Effects of Ultraviolet Light
In Summary
7. Recovery Processes
Photorecovery
The Mechanism of Photorecovery
"Catalase" Restoration
In Summary
8. Replication and Cell Division
Normal Cell Division
The Energetics and Kinetics of Cell Growth and Replication of Parts
The Mitotic Cycle
Replication of DNA, RNA, and Protein Molecules
Ultraviolet Light and the Timing of Cell Division
Delay of Cleavage in the Sea Urchin Egg
Locus of Action
Photorecovery
The "Refractory" Period
Relationship with Some Other Effects
Increase in Growth Rate in Cultures of Microorganisms
In Summary
9. Inherited Changes
Mutation Within the Nucleus
Gene Mutation
Chromosome Aberrations
Polyploidy
Crossing-Over
Somatic Mutation
Inheritance and Inherited Changes in Microorganisms
Mutations
Cytoplasmic Inheritance and Nucleocytoplasmic Relationships
Killer Strains in Paramecium
Bacterial Transformations
Adaptation
Differentiation
Inheritance of the Tendency to Develop Cancer
The Cancer Cell
10. Developmental Growth
Some Studies of Regeneration
11. Acute Effects on Skin
Penetration of Ultraviolet Light
Sunburn of Human Skin
Erythema
Suntan
Immunity to Sunburn
Sunburn as an Inflammatory Response
Hyperplasia
Effects on Mouse Skin
Effect of Visible Light
In Summary
Part III. Experimental Carcinogenesis with Ultraviolet Light
12. The Experiments
Quantitative Measurements of Tumor Development
Dosage and Development Time
Dose-Rate Dependence
Wavelength Dependence
Effect of Temperature
Tumor Types
Photorecovery
13. Cell Proliferation and the Growth of Tumor Masses
14. Quantitative Interpretation of the Experiments
Some Ideas That Do Not Fit
Are There Separable Periods of Induction and Growth?
Hypotheses Involving Somatic Mutation
Constant Acceleration of Growth Rate
An Approximate Model
The Completed Model
In Summary
15. Some Justifications and an Extrapolation
The Growth Curve
Clone Populations
Minor Effects
An Extrapolation
In Summary
16. Some Speculation About the Mechanism of Carcinogenesis
The Tem: A Hypothetical Particle
Are the Tems Virus Particles?
Is the Tem a Mutated Gene?
Control of Tumor Growth
The Question of Separable Stages in Cancerization
Are Immediate Chemical Carcinogens Formed by Ultraviolet Light?
Is the Tem a Common Denominator in Cancer?
In Summary
Part IV. Some Practical Considerations
17. Sunlight and Cancer of the Skin of Man
Skin Color and Cancer of the Skin
Topographical Distribution of Skin Cancer in Man
Distribution of Skin Cancer with Latitude
Relative Incidence in Indoor and Outdoor Workers
Other Diseases Caused by Light
In Summary
Prophylactic Considerations
18. Some Problems of Evaluation
Accumulation of Effect of Environmental Carcinogens
Cancer in the Individual
Evaluation of Carcinogenic and Therapeutic Agents
Part V. Envoi
References
Index