History of the medical uses of radiation: regulatory and voluntary standards of protection.

The main focus of this paper is on the historical development of safety standards in the use of radiation or radioactive materials in medicine. However, to provide better understanding and perspective on this history, it must be interwoven with major events and advancements in the development and use of radiation, particularly in the field of medicine. Since this history, as well as that of major events that stimulated the development of radiation protection standards, is extensive, only a very brief overview can be given here. Thus, a sufficient list of references is also provided to allow further examination of detailed historical documentation, and to provide an easier entry into further research. Also, some identification of individuals who have made important contributions to the development of standards, but who are not widely identified in either the relevant standards or the historical literature, is included. This will aid the serious historian in examining files of organizations to uncover facts or rationale that could better explain historical events or developments.

Influence of paternal immunity on idiotype expression of offspring.

The immune response of the rat to group A streptococcal carbohydrate (SACHO) and an associated idiotype, Id-1, was used to examine the effect of paternal immunity on Id-1 and SACHO-specific antibody expression by the offspring. First litters, conceived before immunization of the father, had significantly higher Id-1 levels than litters conceived by the same parental pairs after hyperimmunization of the father (P greater than 0.01). Total anti-SACHO levels were not affected. The effect appeared to be independent of the level of Id-1 expressed by the father or grandfather. No significant difference in Id-1 production was found between offspring of actively immune, neonatally Id-1 suppressed fathers and fathers expressing high levels of Id-1. We suggest that the paternal immunoregulatory influence acts via the maternal immune system to modify the idiotype repertoire expressed in the immune response of the offspring, and is not the result of genetic transmission of a trait acquired by the father. Some possible mechanisms of transmission are discussed.