PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 15489947

One thing leads to another.

Jules Hirsch
View original source ↗Export metadata ↓

Abstract

In 1956, the JCI published an article by Vincent Dole on a method for titrating plasma fatty acids that uncovered the importance of fatty acids as a substrate for glucose metabolism. When asked to prepare a historical perspective on this very popular paper, I paid Dole a visit and we reminisced. His answer to my question of how he came to do this work on plasma fatty acids was: "Well, one thing leads to another." Let me remind the reader of what "things" were like in 1956 and how they might have related to Dole's important contribution.

Explore related subjects

Blood Chemical AnalysisEnergy MetabolismFatty AcidsGlucoseHistory, 20th CenturyHumansUnited StatesAutobiographyBiographyHistorical ArticleJournal ArticlePortrait

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Jules Hirsch. 2004. One thing leads to another.. https://doi.org/10.1172/jci22993

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Detection of Delta9-tetrahydrocannabinolic acid A in human urine and blood serum by LC-MS/MS.

Delta9-tetrahydrocannabinolic acid A (Delta9-THCA-A) is the precursor of Delta9-tetrahydrocannabinol (Delta9-THC) in hemp plants. During smoking, the non-psychoactive Delta9-THCA-A is converted to Delta9-THC, the main psychoactive component of marihuana and hashish. Although the decarboxylation of Delta9-THCA-A to Delta9-THC was assumed to be complete--which means that no Delta9-THCA-A should be detectable in urine and blood serum of cannabis consumers--we found Delta9-THCA-A in the urine and blood serum samples collected from police controls of drivers suspected for driving under the influence of drugs (DUID). For LC-MS/MS analysis, urine and blood serum samples were prepared by solid-phase extraction. Analysis was performed with a phenylhexyl column using gradient elution with acetonitrile. For detection of Delta9-THCA-A, the mass spectrometer (MS) (SCIEX API 365 triple-quadrupole MS with TurboIonSpray source) was operated in the multiple reaction monitoring (MRM) mode using the following transitions: m/z357 --> 313, m/z357 --> 245 and m/z357 --> 191. Delta9-THCA-A could be detected in the urine and blood serum samples of several cannabis consumers in concentrations of up to 10.8 ng/ml in urine and 14.8 ng/ml in serum. The concentration of Delta9-THCA-A was below the Delta9-THC concentration in most serum samples, resulting in molar ratios of Delta9-THCA-A/Delta9-THC of approximately 5.0-18.6%. Only in one case, where a short elapsed time between the last intake and blood sampling is assumed, the molar ratio was 18.6% in the serum. This indicates differences in elimination kinetics, which need to be investigated in detail.

Blood Chemical Analysis↗