84 KARL FOLKERS 



(including adenosine triphosphate) decreased and the inorganic phos- 

 phorus increased in the liver and kidneys during the development of 

 the deficiency. Changes in the adenosine phosphates may involve the 

 metabolism of the purines. 



Deficiency of the factor resulted in a lowering of the serum phos- 

 phatase level. 



Administration of the factor resulted in a return to normal levels for 

 blood phosphorus and calcium, and prevention of the deposition of col- 

 loidal calcium phosphate in the muscle. Prolonged administration of the 

 factor resulted in removal of even large deposits of calcium phosphate 

 from the tissues. 



Significant changes in the albumin-globulin ratio of the plasma pro- 

 teins also took place during the deficiency. 



It seems apparent that this factor has a regulatory effect upon phos- 

 phorus metabolism (Table XV). 



The work on the isolation of the antistiffness factor showed that 



TABLE XV 



Physiological Studies on the Antistiffness Factor (van Wagtendonk and 



coworkers, 1943-1945) 



No effect on creatine excretion — vitamin E deficiency produces severe 

 creatinuria. 



Easily hydrolyzable P fraction decreases and inorganic P fraction increases. 



Low serum phosphatase level. 



Administration of factor resulted in normal levels of blood P and Ca. 



Administration of factor resulted in removal of calcium phosphate deposits. 



Changes in albumin-globulin ratios in plasma proteins take place. 



Conclusion : Factor has regulatory effect on phosphorus metabolism. 



raw cream was not a satisfactory source for the successful isolation of 

 the factor since such large amounts of raw cream would be needed. 

 Fifty-five gallons of raw cream gave only 3 mg. of a concentrate of the 

 factor which was curative at a dosage of o.iy. 



Other raw materials were tested as a source of the factor. Table XVI 

 contains a summary of some of the results of tests on other materials. 

 Potato, beef muscle, liver, and alfalfa have about one-half as much ac- 

 tivity as raw cream. Yeast, broccoli, soybean, and beet molasses had no 



