Ronnee Strickland

Posted by riyadhassan on April 18th, 2021

The work of Ronnee Strickland in Fibrinolysis to the Plasminogen–Plasmin System and Beyond: A Remarkable Growth of Knowledge, with Personal Observations on the History of Fibrinolysis.

Liquid chromatography electrospray ionization mass spectrometry (MS) with a triple quadrupole MS was once used to pick out regarded and novel heterocyclic fragrant amines (HAAs) in human urine. The identities of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (8-MeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) have been established by using their product ion spectra. The steady impartial loss scan mode was once employed to probe for different analytes in urine that show the transition [M + H]+ → [M + H − CH3•]+•, which is frequent to HAAs containing an N-methylimidazo moiety, and led to the detection of a in the past unreported isomer of 8-MeIQx [Holland, R., et al. (2004) Chem. Res. Toxicol.17, 1121−1136]. We now document the identification of any other novel HAA, 2-amino-1-methylimidazo[4,5-b]quinoline (IQ[4,5-b]), an isomer of the effective animal carcinogen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ). The quantities of IQ[4,5-b] measured in the urine of human volunteers who ate up grilled pork ranged from 15 to 135% of the ingested dose, whilst the quantities of 8-MeIQx and PhIP excreted in urine had been on common <2% of the ingested dose. Base therapy of urine at 70 °C extended the concentrations of 8-MeIQx and PhIP by using as a great deal as 6-fold, indicating the presence of segment II conjugates; however, the quantity of IQ[4,5-b] improved via greater than 100-fold. IQ[4,5-b] used to be additionally detected in the urine of vegetarians following base hydrolysis. The formation of IQ[4,5-b], however now not IQ, 8-MeIQx, or PhIP, additionally passed off in urine incubated at 37 °C. Creatinine and 2-aminobenzaldehyde are probably precursors of IQ[4,5-b]. The detection of IQ[4,5-b] in the urine of each meat eaters and vegetarians suggests that this HAA may also be current in nonmeat staples or that IQ[4,5-b] formation can also appear endogenously inside the urinary bladder or different organic fluids.