19101 



FOODS — HUMAN NUTRITION. 859 



liuiiiiin milk iiiiglit ho attribuU'd to llie presence of lulrenalin in different 

 amounts, the cftVct of botli l^inds of milk iipon smooth nuisoie was determined. 



It was fovmd that cow's milk produced a contraction in the muscle similar to 

 that produced by a solution of adrenalin, and that human milk produced only 

 a very slight contraction. While the resemblance to the adrenalin curve was 

 (luite marked, sufhcient evidence was obtained to indicate tliat the contraction 

 was not due to adrenalin. Further experiments, conducted with a view to de- 

 termining the cause of the contraction established the fact that dialysed cow's 

 milk, with the addition of 3 per cent of milk sugar, gave a curve with smooth 

 muscle practically identical with that of human milk. This suggests the prac- 

 ticability of using dialysed cow's milk in infant feeding. 



While the question of the cause of the effect of milk upon smooth muscle Is 

 still open, the author feels that further evidence is given by the experiments re- 

 ported to support the view tliat the salts and milk sugar are partly responsible 

 for the action. 



Kegeneration of blood serum^ proteins, W. J. Kerb, S. H. Hurwitz, and G. H. 

 Whipple {Amer. Jour. Physiol., 47 (1918), No. 3, pp. 356-392, fig. 1). — The re- 

 sults of a study of the regeneration and source of blood proteins, their fluctua- 

 tion under abnormal conditions, and their function in the body economy are 

 presented in the following papers : 



I. Influence of fasting; upon curve of protein regeneration following plasma, 

 depletion. — Dogs were used as experimental animals, and plasma depletion was 

 effected by bleeding the animal from the artery and introducing into the vein 

 red corpuscles washed and suspended in Locke's solution. By this method, the 

 blood serum proteins, as measured by the refractometrie method, could be re- 

 duced to a low level (33 per cent or even 20 per cent of normal). 



The regeneration took place very slowly, whether food was administered or 

 not, complete regeneration occupying from 7 to 14 days when the original de- 

 pletion removed 50 per cent or more of the total serum proteins. The ability of 

 the body to regenerate serum pi-oteins while fasting and the lack of evidence 

 of any constant fluctuation in serum proteins in association with periods of 

 fasting or heavy protein feeding are thought to indicate that the serum pro- 

 teins are not concerned as intermediary products between food protein and 

 body tissue or parenchyma protein, and that their formation under certain cir- 

 cumstances may be attributed to the body proteins. 



II. Influence of diet upon curve of protein regeneration following plasma de- 

 pletion. — Experiments are reported which supplement those noted above by 

 showing the effect of different diets upon serum protein regeneration. 



The regeneration was found to be more rapid and complete upon a meat or 

 mixed diet than in fasting, and more rapid upon a meat diet than a bread and 

 milk diet. Following plasma depletion there was an average regeneration of 1 

 per cent of the total serum proteins within the next 2-1 hours^ independent of 

 food, shock, or infection. This is thought to represent the absolute maximum 

 production under the greatest stimulus. 



It is pointed out that regeneration of serum proteins on a meat diet after a 

 50 per cent depletion and regeneration of liver cell protoplasm after a 50 per 

 cent necrosis both require from 5 to 7 days, suggesting that the body has the 

 same difiiculty in regenerating its serum proteins that it does in the con- 

 struction of cell protein. 



III. Liver injury alone: Liver injury and plasma depletion: The Eck fistula 

 comhined with plasma depletion. — In this paper experiments are reported 

 W'hich show that " liver injury tends to lessen the amount of circulating blood 

 serum proteins, and the presence of liver injury tends to retard the regenera- 

 tion of serum proteins after an initial plasma depletion. Furthermore, the 



