794 URINE. 



ESBACH'S * Method. The acidified urine (with acetic acid) is poured into a 

 specially graduated tube to a certain mark, and then the reagent (a 2-per cent 

 citric-acid and 1 per cent picric-acid solution in water) is added to a second mark, 

 the tube closed with a rubber stopper and carefully shaken, avoiding the pro- 

 duction of froth. The tube is allowed to stand twenty-four hours, and then the 

 height of the precipitate on the graduation is read off. The reading gives directly 

 the quantity of proteid in 1000 parts of the urine. Urines rich in proteid must 

 first be diluted with water. The results obtained by this method, are, however, 

 dependent upon the temperature; and a difference in temperature of 5 to 6.5 

 C. may cause an error of 0.2-0.3 per cent deficiency or excess in urines containing 

 a medium quantity of proteid (CHRISTENSEN and MYGGE). The method sug- 

 gested by TSUSCHIJA 2 seems to be more reliable, and consists in precipitating the 

 proteid by an alcoholic solution of phosphotungstic acid containing hydrochloric 

 acid. 



Other methods for the approximate estimation of proteid are the optical 

 methods of CHRISTENSEN and MYGGE, and of WALBUM, S of ROBERTS and STOLLNI- 

 KOW as modified by BRANDBERG, with HELLER'S test, which has been simplified 

 for practical purposes by MITTELBACH. The density methods of LANG, HUPPERT 

 and ZAHOR are also very good. In regard to these and other methods we refer to 

 HUPPERT-NEUBAUER'S Harn- Analyse, 10. Aufl. 



There is at present no trustworthy method for the quantitative estimation 

 of proteoses and peptone in the urine. 



Nucleoalbumin and Mucin. According to K. MORNER traces of urinary 

 mucoids may pass into solution in the urine; otherwise normal urine con- 

 tains no mucin. There is no doubt that there may be cases where true 

 mucin appears in the urine; in most cases mucin has probably been mis- 

 taken for so-called nucleoalbumin. The occurrence, under some circum- 

 stances, of nucleoalbumin in the urine is not to be denied, as such sub- 

 stances occur in the renal and urinary passages; still in most cases this 

 nucleoalbumin, as shown by K. MORNER;* is of an entirely different kind. 



All urine, according to MORNER, contains a little proteid and in 

 addition substances which precipitate proteid. If the urine freed from 

 salts by dialysis is shaken with chloroform after the addition of 1-2 p. m. 

 acetic acid, a precipitate is obtained which acts like a nucleoalbumin. 

 If the acid filtrate is treated with seralbumin, a new and similar precipitate 

 is obtained, due to the presence of a residue of the substance which pre- 

 cipitates proteids. The most important of these proteid-precipitating 

 substances is chondroitin-sulphuric acid and nucleic acid, although the 

 latter appears to a much smaller extent. Taurocholic acid may in a few 

 instances^ especially in icteric urines, be precipitated. The substances 

 isolated by different investigators from urine by the addition of acetic 

 acid and called " dissolved mucin " or " nucleoalbumin " are considered 



1 In regard to the literature on this method and the numerous experiments to 

 determine its value, see Huppert-Neubauer, 10 Aufl., 853 and Neuberg, Der Harn, 

 s. 765. 



2 Christensen, Virchow's Arch., 115; Tsuschija, Centralbl. f. Med., 1908. 



3 Deutsch. med. Wochenschrift, 1908. 



4 Skand. Arch. f. Physiol., 6. 



