294 Hubert P. Yockey 



in 1950 and Brues and Sacher (11) in 1952 considered radiation injury and 

 lethality and normal aging from the same point of view and gave an analysis 

 in terms of survival curves. 



In 1953 H. A. Blair (12) emphasized this relationship and extended the notion 

 to internal emitters. He pointed out that the shortening of life, even with bone 

 seekers such as Po, Pu and Ra, is not attributable solely to bone pathology since 

 other tissues are also damaged in a way similar to total body irradiation. Blair's 

 remark is based on observations by Boyd et al. (13) that tissue changes were 

 of the type produced in rats by 550 r whole-body irradiation. In 1954 Furth, 

 Upton, Christenberry, Benedict, and Moshman (14) called attention to this 

 relationship in the case of LAF^ mice exposed to atomic bomb radiation. In 

 the same year Upton, Furth, and Christenberry (15) made the same observa- 

 tion with regard to late effects from thermal-neutron irradiation of RF mice. 



The similarity between aging and radiation damage is paralleled by chemical 

 carcinogens. Cloudman, Hamilton, Clayton, and Brues (16) reported that 

 mice painted with a carcinogenic agent (methylcholanthrene) exhibited a life 

 shortening not to be explained by a single pathology. They indicated an analogy 

 between life shortening from hydrocarbons and total-body irradiation. 



Russell (17) has recently found that the increased prenatal and infant 

 mortality of offspring from irradiated parents continues throughout life and is 

 reflected by a reduced average life. He studied only the offspring of male mice 

 irradiated by neutrons from an atomic weapon. Presumably, the effect is 

 general and applies to offspring of both male and female animals subjected to 

 any ionizing radiation. The relation of this work to that of Russ and Scott is 

 clear and the need for detailed study is paramount. 



Some may feel that establishing a relation between two unexplained effects 

 gets one nowhere. However, as Platt (18) points out, such a relationship may 

 help one effect to explain the other. 



The concept of premature aging as a measure of damage from various 

 deleterious agents seems to be well enough established for practical use in 

 understanding the nature of biological damage. Information theory may well 

 have a contribution to make to the elucidation of these problems of our times 

 which are so important from so many points of view. 



H. P. Y. 



REFERENCES 



1. W. P. Davey: The effect of x-rays on the length of life of Tribolium confusiim. Gen. 

 Elect. Rev. 20, 174-182 (1917). (An article nearly identical to this is to be found as 

 follows: W. P. Davey: The effect of x-rays on the length of life of Tribolium confusum. 

 J. Exp. Zool. 22, 573-592 (1917).) 



2. W. P. Davey: Prolongation of life of Tribolium confusum apparently due to small doses 

 of x-rays. Gen. Elect. Rev. 22, 479^83 (1919). 



3. J. W. GowEN and J. Stadler: Irradiation effects on viability of Drosophila melanogaster. 

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4. E. Lorentz: Effects of long-continued total-body gamma irradiation on mice, 

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5. G. A. Sacher: On the statistical nature of mortality, with especial references to 

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6. J. W. Gowen: private communication (1957). 



7. S. Russ and G. M. Scott: Some biological effects of continuous gamma irradiation, 

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