Figure 1
Bronchoalveolar lavage phosphatidylcholine mass spectra from a healthy control for precursor scans of P184 (A) (endogenous phosphatidylcholine composition) and precursor scans of P193 (B) (newly synthesised deuterated phosphatidylcholine composition at 24 hours after methyl -D 9 choline infusion). The relative signal intensity of spectra B is nearly one hundredth of spectra A. The m/z 678 represents an internal standard of PC14:0/14:0. The methyl-D9-labelled phosphatidylcholine composition consisted of phosphatidylcholine species with 9 mass units higher than that of endogenous composition. PC, phosphatidylcholine; m/z, mass to charge ratio.