1917] VETEETNARY MEDICINE. 877 



!iud the elimination of the Carrel tube simplifies the dressing, the problem of 

 transportation of the wounded, and the time taken for the periodic flushing. 



The relation between the thromboplastic action of cephalin and its degree 

 of unsaturatiou, J. McLean {Amer. Jour. Physiol., JfS (1917), A^o. 4. PP- 586- 

 596). — Experiments with various samples of cephalin have shown that its 

 thromboplastic action bears a direct relation to its degree of unsaturatiou. The 

 greater the degree of unsaturation the greater the thromboplastic activity. 

 Cephalin saturated bej'ond a certain degree, either by reduction or oxidation, 

 loses completely its thromboplastic activity. The material in solution which 

 has become saturated or partly saturated yields an acid reaction and retards 

 the coagulation of blood. With increasing saturation the material gradually 

 loses its property of solution in ether and chloroform. 



It is noted that cephalin is most effective in its coagulative power shortly 

 after its isolation from the tissues. 



The reaction of sera as a factor in the successful concentration of antitoxic 

 sera by the methods at present in use, Annie Homer (Biochcm. Jour., 11 

 {1911), No. 1, pp. 21-89, figs. 2).— The results of the study reported show that 

 in the Banzhaf^ method for concentration of antitoxic sera the uncertainties 

 of filtration are due to no account having been taken of the reaction of the 

 serum, and that, as the precipitating power of 30 per cent ammonium sulphate 

 is not appreciably increased during the heating, a certain amount of euglobulin 

 escapes precipitation with the first fraction precipitate and appears in colloidal 

 suspension in the final product. " The uncertainties in the filtration of the 

 hot serum-ammonium-sulphate mixtures in the above method can be obviated 

 by an adjustment of the hydrogen ion concentration. The filtration can also be 

 improved by the addition of sodium chlorid to the mixtures, but in this case 

 the improvement is due to a specific action of salt on the globulins." 



Euglobulin can be completely eliminated by adjustment of the hydrogen ion 

 concentration of the serum mixtures to the point at which the desired increased 

 precipitation is assured, by brine extraction of the second fraction precipitate 

 containing the pseudoglobulin-antitoxin combination, subjecting the serum to a 

 preliminary prolonged heating at from 57 to 58° C, and the addition of organic 

 substances such as phenol and its homologues, ether, or chloroform. " The 

 extent of the heat denaturation of the serum proteins during the heating of 

 serum at 57° for several hours is also influenced by the hydrogen ion concen- 

 tration of the serum and can be controlled by the adjustment of the latter. 

 The denaturation induced by heat in alkaline sera apparently does not involve 

 the same type of change as that induced in acid sera." 



Equilibria in precipitin reactions. — The coexistence of a single free antigen 

 and its antibody in the same serum, S. Bayne-Jones (Jour. Expt. Med., 25 

 (1917), No. 6, pp. 837-853, fig. 1).—In the study reported the purified proteins, 

 edestin from hempseed and crystalline ovalbumin from fresh eggs, were used 

 as antigens. Although the albumin isolated was considered as pure as is ob- 

 tainable by chemical means, moderately severe anaphylactic reactions were 

 produced by it in animals sensitized with ovoglobulin. It is noted that " ana- 

 phylactic tests of the individuality of a protein can not be any longer regarded 

 as the criterion of the purity of the substance as an antigen. . . . 



" With edestin and crystalline egg albumin as antigens, phases in the pre- 

 cipitin reaction were found in which these substances and their specific pre- 

 cipitins could be demonstrated to be coexistent but ununited in the same serum. 

 When edestin or crystalline egg albumin is injected into a rabbit immunized 

 thereto, the antigen may be found in the circulating blood during 48 hours after 



» Collected Studies Research Lab. Dept. Health N. Y. City, 4 (1908-9), pp. 230-232. 



