To determine if unlabelled cells in the above fluorescence assay had accumulated peptide below detectable levels, we next evaluated peptide incorporation using the more sensitive fluorescenceactivated cell sorting (FACS) technique. Cells were incubated for 1 hour with media containing increasing concentrations of carboxyfluoresceintagged peptide. To discriminate between potentially nonspecific membranebound versus internalized fluorochrome, peptidetreated cells were incubated with trypsin prior to FACS analysis.21 At 10 of carboxyfluoresceintagged peptide, 95.4 3.3 % of 9L and 32.7 4.3 % of F98 cells internalized the peptide, while at 20 most glioma cells internalized the peptide (100 0.3 % of 9L and 72.1 6.9 % of F98 glioma cells).I read an article some months ago which suggested that new brain cells were activated when a person habitually used the less dominant appendages in the more dominant manner (the instinctive approach). I had a chance to apply this theory several years ago