Objective To determine the impact of PEE with different ethanol concentration extract on the activity of tyrosinase in B16 melanoma and to explore the feasibility of PEE used as skin whitening agent make use of a model organism .Methods 30%, 50%, 70%, 95%, different concentration of ethanol reflux got four kinds of PEE alcohol extract, respectively.And selected the most active inhibition to mushroom tyrosinase ( PEE30、PEE50、PEE70、PEE95).The effect of extracts from the selected on B16 cell model was determined by MTS, NaOH splitting decomposition, L-DOPA oxidation progress.The change in protein expression level after ethanol extract of PEE was determined by Western bolt.Results The capacity of inhibition to mushroom tyrosinase in each concentration of PEE extraction, but PEE70 had the most active inhibition.When challenged with B16 cell model, PEE70 showed the capacity of decrease in tyrosinase activities and melanin synthesis (P<0.01) and had a does dependence ;it also decreased Tyrosinase and TRP-1 expression compared with control B16 cells.Conclusion These data support the idea that PEE can restrain melanogenesis, through its inhibitory effect on the activity of tyrosinase.

Behavioral adjustment plays an important role in the treatment and relapse of drug addiction. Nonetheless, few studies have examined behavioral adjustment and its plasticity following error commission in methamphetamine (METH) dependence, which is detrimental to human health. Thus, we investigated the behavioral adjustment performance following error commission in long-term METH addicts and how it varied with the application of repetitive transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (DLPFC). Twenty-nine male long-term METH addicts (for > 3 years) were randomly assigned to high-frequency (10 Hz, n = 15) or sham (n = 14) rTMS of the left DLPFC during a two-choice oddball task. Twenty-six age-matched, healthy male adults participated in the two-choice oddball task pretest to establish normal performance for comparison. The results showed that 10 Hz rTMS over the left DLPFC significantly decreased the post-error slowing effect in response times of METH addicts. In addition, the 10 Hz rTMS intervention remarkably reduced the reaction times during post-error trials but not post-correct trials. While the 10 Hz rTMS group showed a more pronounced post-error slowing effect than the healthy participants during the pretest, the post-error slowing effect in the posttest of this sample was similar to that in the healthy participants. These results suggest that high-frequency rTMS over the left DLPFC is a useful protocol for the improvement of behavioral adjustment after error commission in long-term METH addicts.
Adjustment Disorders ; etiology ; therapy ; Adult ; Amphetamine-Related Disorders ; complications ; therapy ; Case-Control Studies ; Central Nervous System Stimulants ; adverse effects ; Choice Behavior ; physiology ; Functional Laterality ; Humans ; Male ; Methamphetamine ; adverse effects ; Middle Aged ; Prefrontal Cortex ; physiology ; Reaction Time ; physiology ; Transcranial Magnetic Stimulation ; methods ; Young Adult