Michael D. Rush

Learn More
The course of alkaloid accumulation and laticifer cell appearance was compared in germinating P. bracteatum seedlings. Seedlings of various ages (0–14 days old) were analyzed for their dopamine, thebaine, morphinan alkaloid immunoreactivity, and benzophenanthridine alkaloid levels. Simultaneous electron microscopic studies revealed that seedlings were(More)
Human brain tumors (obtained as surgical specimens) and nude mouse-borne human neuroblastomas and gliomas were analyzed for sigma and opioid receptor content. Sigma binding was assessed using [3H]1,3-di-o-tolylguanidine (DTG), whereas opoid receptor subtypes were measured with tritiated forms of the following: mu, [D-ala2,mePhe4,gly-ol5]enkephalin (DAMGE);(More)
Fractionation of Papaver bracteatum Arya II Lindl. latex on Renografin step gradients revealed that 43% of the dopamine was compartmentalized along with alpha-mannosidase (40%) in vacuoles sedimenting in the 2% fraction. Twenty-two percent of the dopamine was in the supernatant, but a corresponding amount (18%) of alpha-mannosidase was also present(More)
Procyanidins are polyphenols abundant in dietary fruits, vegetables, nuts, legumes, and grains with a variety of chemopreventive biological effects. Rapid structure determination of these compounds is needed, notably for the more complex polymeric procyanidins. We review the recent developments in the structure elucidation of procyanidins with a focus on(More)
To expedite the identification of active natural products in complex mixtures such as botanical extracts, a magnetic microbead affinity selection screening (MagMASS) procedure was developed. This technique utilizes target proteins immobilized on magnetic beads for rapid bioaffinity isolation of ligands from complex mixtures. A MagMASS method was developed(More)
To overcome limiting factors in mass spectrometry-based screening methods such as automation while still facilitating the screening of complex mixtures such as botanical extracts, magnetic microbead affinity selection screening (MagMASS) was developed. The screening process involves immobilization of a target protein on a magnetic microbead using a variety(More)
RATIONALE Electrospray mass spectrometry methods for the analysis of phosphatidylcholines (PCs) routinely include ammonium acetate or ammonium formate in the mobile phase. In an effort to justify and optimize the use of these additives, we investigated possible functions of ammonium compounds in the ionization of PCs. METHODS Because PCs contain a(More)
  • 1