778 EXPERIMENT STATION RECOED. 



The relation of such action as a probable etiological factor of intestinal auto- 

 intoxication and other pathological conditions is indicated. 



The fate of amins derived from proteins in the animal organism, M. Gug- 

 genheim and W. LoFFLEB (Biochcm. Ztschr., 12 (1916), No. 5-6, pp. 325-350, 

 figs, 7). — It has been demonstrated that isoamylamin, phenylethylamln, para- 

 oxyphenylethylamin, indolethylarain, and /3-imidazolethylamin are detoxicated 

 in the animal organism. This detoxication results from a deamination and 

 subsequent oxidation, the end product being an acid with the same number of 

 carbon atoms as the original amin. As intermediate products in the oxidation 

 of the amins, alcohols were isolated and identified by perfusing the isolated 

 liver with the respective amins. The fact was thus established that the liver 

 is able to oxidize certain alcohols to their corresponding acids. 



Normal human blood and serum, and also that of the rabbit, exhibitetl a tonic 

 effect on the isolated guinea-pig intestine. The active principle causing this 

 effect was found to be soluble in alcohol and thermostable. 



Studies in anaphylaxis, XIV-XVII, II. Weil (Jour. Immunol., 1 (1916), 

 Xo. 1, pp. 1-Ji'.>). — Four studies are bore reported, continuing previous work 

 (E. S. R., 33, p. 82). 



XIV. On the relation hctwccyi precipitin and }(en^<iitizin (pp. 1-lS). — From 

 experimental data it has been demonstrated that passive sensitization toward 

 horse serum can be induced in guinea pigs by injecting intraperitoneally pre- 

 cipitates produced by liorse serum and the serum of a rabbit inununized against 

 horse serum. The same results can be obtained by using crystalline egg 

 albumin. Certain quantitative relations have been found to exist between 

 antigen and antibody in producing the precipitates which do not vary outside 

 of certain fairly wide limits. A great excess or deficiency of either factor 

 produces a preciiiitate wliich fails to sensitize passively. 



"The precipitating substance of immune sera is competent to sensitize guinea 

 pigs passively. In other words, precipitin is also sensitizin [the substance 

 which confers sensitization!. It is conceivable, but improbable, that tliere may 

 be a fraction of precipitin which lacks the sensitizing function. 



"Antibody may be deprived of its precipitating function by heat without 

 suffering a very material diminution in its sensitizing value. This observation 

 corresponds with the previously known fact that ' precipitoid,' or heate<l pre- 

 cipitin, has retained its combining power with antigen, although it has lost its 

 precipitating power. The precipitating, or ergophore group, is said to be tber- 

 molabile; the sensitizing or haptophore group, to be thermostable. 



"Only the combining (or haptophore) group is essential to passive sensitiza- 

 tion. Anaphylaxis therefore consists simply in the cellular reaction due to the 

 fixation of antigen by cellular antibody. These new data therefore confirm and 

 establi-sh the theory of anaphylaxis supported in previous studies of this series. 



"The fact that the coexistence of antigen in the same fluid may inhibit the 

 precipitating power of antibody while only partially interfering with the sensi- 

 tizing function, as in the prozone experiments, may explain the divergence in 

 the literature between those who maintain that precipitin and sensitizin run 

 parallel in immune sera and those who deny this relationship. 



" The phenomenon which has been descrilied as dissociation of the precipitate, 

 which probably occurs within the body and which may be lmitate«l by various 

 laboratory procedures such as extraction by sodium carbonate, sets free 

 antibody in a form which sensitizes passively but fails to give the precipitin 

 reaction. Such a factor, likewise, would upset the normal parallelism between 

 sensitizin and precipitin. 



" The foregoing consideration may serve to explain the fact that the presence 

 of antibodies may be demonstrated by means of passive sensitization in spite of 



