igii] Jacob Rosenhloom 75 



already been indicated. Aside from the nucleoprotein combination, 

 carbohydrate also exists in cells combined with protein in the form 

 of glycoproteins. These substances are usually produced by special 

 cells and are formed along with other secretions, as in the case of 

 saliva. The brain and nervous System of the higher animals con- 

 tain complex Compounds called cerebro-galactosides. In these 

 lipins we often find galactose-yielding radicals are united to fatty 

 acids groups and also to nitrogen and phosphorous derivatives. 

 Finally, glucose appears in a somewhat similar combination called 

 jecorin, which occurs in the liver, heart-muscle, and other organs. 

 The nature of jecorin is unknown and further work upon it is very 

 desirable. 



Intracellular carbohydrates are freely soluble in the associated 

 water; some are insoluble in it. The soluble intracellular carbo- 

 hydrates are diffusible, and easily pass back and forth in the cells 

 and through the cell "membranes." Although they are compara- 

 tively Stahle substances, the intracellular carbohydrates combine with 

 oxygen, with water, with salins, with carbohydrates, with lipins, 

 and with proteins. That intracellular carbohydrates are involved 

 more actively in intracellular dynamics and reconstructions than 

 I have here indicated is a belief which all of us share but on which 

 none of us is able as yet to say very much that is definite. 



IV. INTRACELLULAR LIPINS 

 Jacob Rosenbloom 



In this discussion I shall refer to lipins in terms of the Classifi- 

 cation given on page 52. 



It is well known that normal organs like the heart and kidneys 

 will show no evidence of fat, on section, whereas chemical analysis 

 may indicate that 15 to 20 per cent. of the dry weight of the organ 

 is "fatty" in nature. This "masked" fat is combined with other 

 constituents of protoplasm. In pathological organs which show 

 microsccpically the presence of an abundance of fat, the total 

 amount of fat may be raised above the normal. As a result of cer- 

 tain postmortem or acute changes in such cases, the fat which 

 normally is "masked" is liberated from its combinations and 



