472 
HEMATOLOGY 
DISCUSSION 
Chairman Seegers : Thank you, Dr. Dodds. 
We'll now entertain questions. Are there any 
questions to ask Dr. Dodds at the present time ? 
E. J. W. Bowie, Mayo Clinic, Rochester, Min- 
nesota: I think that was a very fascinating 
study. The relationship, as you mentioned, of 
the stimulating activity of the liver to the possi- 
ble mechanism of von Willebrand's disease is 
extremely intriguing. I wonder if you have done 
any work on the activity that stimulates factor 
VIII release from the spleen to see if it corrects 
the platelet retention in dogs with von Wille- 
brand's disease? 
Dr. Dodds : We haven't done that yet, because 
it's quite difficult isolating the liver fraction and 
we have lots of experiments we want to use it 
for. 
Chairman : I was wondering about one point 
and would like you to comment on it. You say 
that you can now get positive reactions to anti- 
body tests quite commonly when you have a 
hemophilia-A. In other words, the molecule is 
there. About fifteen years ago we extracted 
hemophilia plasma with ether and developed 
factor VIII activity. Would that fit in with your 
findings now? 
Dr. Dodds: I think. Dr. Seegers, that's a 
very difficult question. Several years ago my 
former colleagues reported in vivo experiments 
in which they infused ether extracted serum 
and corrected factor IX deficiency. It would be 
impossible to speculate whether the experiments 
we performed are in any way related to the 
correction of hemophilic plasma by ether ex- 
traction. 
Chairman: I have one more question along 
that same line. Do you think that factor IX pro- 
duction is dependent on Vitamin K? 
Dr. Dodds : I don't know. I think the whole 
prothrombin relationship with warfarin and 
Vitamin K is quite complex. 
Chairman: Well, is there anything in your 
experiments that would lead you to believe that 
factor IX is not synthesized by a dependence on 
Vitamin K? 
Dr. Dodds : No. We have done many perfu- 
sions with warfarin which were not discussed 
today. Our results suggest that factor IX syn- 
thesis is dependent upon Vitamin K. 
