143 



- 1 9 4 4 - 



411. ZAHL, P. A. and BJERKNES, C. 



Effect of the endotoxin of Shigella paradysenterlae ^n pregnancy 

 in rabbits. 



Proc. Soc. Exper. Biol. Med. 56:153-155, 1944 



12. ZAHL, P. A. and HUTNER, S. H, 



Protection against' the endotoxins of some gram-negative bacteria 

 conferred by immunization with heterologous organisms 



Am. J. Hyg. 39:189-196, 1944 



Homologous protection by the endotoxins of 3 gram-negative or- 

 ganisms (S. typhimuriuin , Sh . paradysenteriae and Rhodospirillum 

 rubrum ) was most effective for the mouse immunized one week 

 before injection of 4 times the LD^q dose. Trichloracetic acid 

 extracts of Shigella and S. typhimurlum endotoxins produced 

 similar resultsT HFterologous protection was leas efficient 

 but still significantly protective. Toxins of 'rough' variants 

 of bacteria may form a link between toxic nucleoprotelns and 

 the complex antigens. 



413. ZAHL, P. A. and HUTNER, S. H. 



Temperature factors in the action of certain bacterial endotoxins 



Proc. Soc. Exper. Biol. & Med. 56:156-158, 1944 



External heat and cold did not affect the production of tumor 



hemorrhage and vaginal bleeding found after the injection 



of bacterial endotoxins in gravid mice. Histopathologic effects 



and temperatures produced were unrelated. It is possible that 



gram-negative bacteria possess endotoxins which act as neural 



poisons. 



414. ZAHL, P. A., HUTNER, S. H. and COOPER, P. S. 



Effect of sulfonamides on toxic and antigenic actions of endo- 

 toxins of certain gram-negative bacteria 



Proc. Soc. Exper. Biol. & Med. 55:4-7, 1944 



Limited protection against the lethal action of bacterial 

 endotoxins is afforded by orally administered sulfonamides. 



