Delta E. Uphoff

Modification of Acute Irradiation Injury in Mice and Guinea-Pigs by Bone Marrow Injections

The problem of finding an agent or a method that will protect against the effects of whole-body irradiation has always been an attractive one, but in recent years many more investigators have been bending their efforts in this direction. The agents or methods brought to light by these investigations may be divided into three groups. To the first group belong those which have to be given prior to the irradiation, one of the best known representatives of this group being cysteine (1). The second group consists of agents or procedures that are used during irradiation; the most effective method of this group is the protection of the exteriorized spleen of the mouse by lead, discovered by Jacobson et al. (2). The third group of protective measures are effective when given post-irradiation. Among these are the intraperitoneal transplantation of spleens after irradiation which, as Jacobson (3) has shown, significantly increases survival of irradiated mice, and the injection of bone marrow following doses which a...

Directional Effects of Acute Total-Body X-Irradiation: Exposure Rate Versus Homogeneity of Exposure1

Survival patterns of NBL/Up mice exposed to 675-800 R of total-body x-radiation depended on direction and rate of exposure. Homogeneous dual exposures administered at 126 R/minute were more effective than those administered at 63 R/minute. Dorsal and dual exposures at 63 R/minute were equally effective, while absorption reduced the effectiveness of ventral exposures. Since cellular repair of hematopoietic tissue was initiated only during exposure, increased homogeneity without increased exposure rate would not increase effectiveness. With rate, direction, and homogeneity influencing the effectiveness of total-body exposures, fallacies inherent in converting total-body exposures to absorbed tissue dose became apparent.