ANEURINE (thiamine) 



Using this method, Y. L. Wang and L. J. Harris ^ found that 

 normal humans excreted 36 to 105 (average 65) fxg. of aneurine per 

 day and that, on administration of a test dose of just over i mg. of 

 aneurine hydrochloride per 10 stones of body^veight, this increased to 

 over 105 jjLg. per day. Excretions of less than 30 fig. per day, rising 

 to not more thaii 45 /xg. after giving the test dose, were taken to 

 indicate sub-optimal levels of intake, whilst values of 15 fxg. per day 

 or less were regarded as indicative of more or less severe vitamin B^ 

 deficiency. 



A somewhat similar method was used by G. M. Hills ^ with similar, 

 though somewhat higher, results. He found that normal humans 

 excreted 50 to 170 (average 100) fig. per day and that, except in 

 thyrotoxicosis, oral administration of a i-mg. test dose of aneurine 

 hydrochloride resulted in the excretion, three hours later, of 26 to no 

 (average 65) fig. In a fully saturated individual, 200 fig. of the test 

 dose were excreted within three hours. H. C. Hou and E. F. Yang,* 

 using a modification of the test devised by E. F. Yang and B. S. 

 Platt,^ in which diazotised _^-aminoacetophenone is the reagent, 

 obtained values of 28 to 170 and to 16 fig. for the daily urinary 

 excretion of normal Chinese adults and beriberi patients respectively. 

 R. C. Guha and B. Ahmad ^ reported values of 84 to 228 fig. for the 

 daily output of normal Indian adults ; this was computed to be 6 to 

 19 % of the intake. 



The test-dose method has been used extensively by various workers 

 in different parts of the world. Some have employed the thiochrome 

 method for estimating the aneurine, some various modifications of 

 the azo reaction and others the yeast growth or the Phycomyces 

 method. Different routes of administration, different test doses and 

 different criteria for assessing the response have also been proposed ; 

 some workers have suggested estimating the aneurine output within 

 twenty-four hours of giving the test dose, others within three hours, 

 and yet others within four hours. ' Again, some workers have recorded 

 the absolute amounts excreted and others the percentage of the test 

 dose excreted. 



Melnick et al.,^ using diazotised ^-aminoacetophenone, found that 

 the average daily excretions by well-nourished men and women were 

 198 and 93 fig. respectively, and that, after oral administration of a 

 5-mg. test dose, 14 and 12 % respectively were excreted within twenty- 

 four hours. Elderly men (66 to 75 years of age) excreted slightly 

 more ameurine than women of the same age.^ I. Magyar ^^ claimed 

 that the excretion within twenty-four hours of less than 18 % of a 

 2- to 10 -mg. test dose administered intravenously was indicative of 

 vitamin B^ deficiency. W. Neuweiler ^^ foimd that the daily urinary 

 excretion of normal women was 45 to 665 fig., of pregnant women on 



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