324 V. N. TARUSOV 



whereas according to your data on yeast, protection occurred even at a pressiu-e 

 of less than 1 atni. 



I experimented on animals. Cats survive oxygen pressures amounting even to 

 3-5 to 4-0 atm. It opens the way to testing the protective effect of oxygen on large 

 animals. 



TABUSOv : Our conditions do not allow us to use animals weighing more than 20 to 

 30 g; it is our limit. 



marcovich: How do you irradiate yeast in agar culture? 



TARUSOV : The agar plate is placed within a cylinder, from which the air is evacu- 

 ated and replaced by the gas mixture. Then the system is transferred into the 

 irradiation chamber. 



marcovich: What is the procedure for transferring yeasts to agar and what is 

 their condition on agar? 



TARUSOV: Special vessels with an agar layer are inoculated with yeast. Yeast 

 spreads over this layer forming a film of jDracticallN' uniform thickness. 



KUziN : What data do you have at yovu- (lisi)osal to warrant the view that the ap- 

 pearance of lipid peroxides you have demonstrated three days after the exposui'e 

 is due to a chemical chain reaction and not to profoimd metabolic disturbances in 

 the lipids which develop at this joeriod in the liver? 



TARUSOV : Regardless of anything else, the appearance of peroxides is not the 

 main index here. I regard it as a result. As I have said, secondary reactions are 

 the reflection of the primary ones. In our ojiinion the basic process is conxiected 

 not with these peroxides, but with ant i -oxidants, which are released as a result of 

 irradiation; release of the anti-oxidants opens the way to oxidation, with no dis- 

 turbance in the general metabolism. 



tummerman: In connection with your very interesting observation that oxidation 

 of lipids gives rise to a visible luminescence I would like to say that it is not a 

 specific peculiarity of the lijiids. We have observed similar luminescence in 

 visible regions of the spectrum in the case of mnnerous proteins, some amino 

 acids and carbohydrates. Even ordinary pa|)er placed in the dark before a 

 sufficiently sensitive receiver and heated to about ISO^C emits visible light of 

 sufficient intensity, probably with two maxima — one in the green, and another 

 in the red region of the spectrum — when no irradiation has been applied. This 

 effect is highly dependent on the presence of oxygen and in general conforms to 

 the same kinetic laws. At oxygen pressures vip to 10 cm the effect does not dis- 

 appear, but it disappears completely at 0-1 cm pressure. 



Do you not think, that such luminescence accompanying oxidation of very 

 different biological substrates, may be related to those very interesting phenomena 

 discovered by Professor Mitchell which were mentioned in Dr. Holmes' report? 



TARUSOV: Of course, there is no c^uestion of heating the animals to LIO '. The 

 luminescence described occurs in normal animals also, but it has only a small 

 intensity; it is activated by irradiation. 



The difference from your data, according to your report, consists in the fact 

 that the spectrum breaks off in the red region, antl there is no maximum. We do 



