During meditation, experienced meditators show more integrated brain networks in the alpha frequency band (8-13 Hz) than novice meditators. EEG measures of network integration—maximum betweenness centrality and leaf fraction—were higher in experienced meditators, while diameter and average eccentricity were lower, indicating more efficient network topology. No differences were found in theta or beta bands. The findings suggest that long-term meditation practice is associated with greater functional integration of alpha-band brain networks.
Conventional liquid chromatography-tandem mass spectrometry (LC-MS/MS) can characterize pharmacokinetics of nonlabeled drugs at a microdose of 1 microg/kg in rats, offering a more accessible alternative to accelerator mass spectrometry (AMS) for microdosing studies. For fluconazole and tolbutamide, exposure was linear between the microdose and doses 1000-fold higher, supporting LC-MS/MS's utility in human microdosing. However, for an investigational compound MLNX, pharmacokinetics in rats were nonlinear, suggesting its microdose pharmacokinetics in humans might not reflect therapeutic doses. These findings indicate LC-MS/MS is adequate for microdose pharmacokinetic assessment in humans, though nonlinearity in some compounds may limit predictability.