A method using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed and validated to detect phencyclidine-type substances in human hair. The method showed good sensitivity, selectivity, and accuracy. It was applied to hair samples from 87 authentic forensic cases, identifying and quantifying nine analytes including ketamine, 2-F-2-oxo-PCE, 2-FDCK, 2-BrDCK, nor2-FDCK, tiletamine, O-PCE, DCK, and norDCK at various concentrations. This approach provides technical support for monitoring abuse of these substances, which are often synthesized as substitutes for controlled drugs.
A low dose of esketamine (2 mg/kg) significantly accelerated awakening from propofol anesthesia in adult C57BL/6J mice. In the prefrontal cortex, esketamine hastened the emergence of γ oscillations and triggered earlier activation of neuronal somata and dendrites in layer V, while delaying activation in layer II/III neurons. It also induced inter-layer phase desynchronization and a premature increase in acetylcholine and 5-hydroxytryptamine levels. The findings suggest that low-dose esketamine facilitates awakening by orchestrating a sequence of neural events in the prefrontal cortex, providing mechanistic insight into paradoxical emergence from anesthesia.