Urine profiling

Specimen contamination may not be immediately apparent on visual inspection. A large peak of glycerol, especially in a female newborn or infant, should be considered an artifact at first and verified by a repeat specimen before raising the possibility of glycerol kinase deficiency. Medium- and long-chain monocarboxylic fatty acids (Cio-Ci8) could be very prominent peaks in a urine profile following contamination... 

A final example of the use of this strategy to examine futile deacetylation comes from work on the beta-blocking drug practolol where a radio-labelled 13C/14C drug was dosed to rats and the urine profiled by HPLC with UV, radioactivity, NMR and MS-MS detection [61]. As shown by the structure below, practolol can be considered to be an analogue of paracetamol with a beta-blocker side-chain ... 

Van der Greel J, Leegwater DC. 1983. Urine profile analysis by field desorbtion mass spectrometry, a technique for detecting metabolites of xenobiotics. Biomed Mass Spec 10(1 ) 1-4. 

Since laboratory measurements commenced, we have used biomarkers however, in the last decade there has been a great deal of discussion and debate about the term biomarker, its definition, and its usage (Colburn 1997 Biomarkers Definitions Working Group 2001 Frank and Hargreaves 2003). The term biomarker is often used to encompass relatively new indices—for example, plasma and urine profiles obtained with nuclear magnetic resonance spectroscopy (NMR), metabonomics, proteomics, etc. (Grandjean et al. 1994 Timbrell, Draper, and Waterheld 1994). However, the term is equally applicable to the traditional core tests. 

Low 18-oxocortisol (aldosterone urinary metabolite, not detectable via gas chromatographic urine profile). 

No direct metabolite of testosterone measurable, not detectable via gas chromatographic urine profile. Sodium intake 100-200 meq/d recumbent (m) upright (j) sodium intake 10 meq/d recumbent 333-999 upright 472-3800. 

The pathological condition induced by exposing an organism to a toxic substance depends on the mode of admission, the quantity, and the type of dosage (acute or chronic). Urine profiling by p-cyclodextrin-modified micellar electrokinetic capillary electrophoresis was used by Zomer et al. to identify the type of cadmium intoxication (acute or chronic).Their dataset of 96 samples was split into a learning set of 60 samples and a test set of 36 samples. Discriminant analysis applied to the first six principal components had better results on the test set (96.97% correctly classified) than did SVM trained on the original measured data (75.76% correctly classified). 

---