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Objective:To observe any stimulatory effect of intermittent theta burst stimulation (iTBS) on the cerebral swallowing cortex and the cerebellar swallowing motor area and to explore the related mechanisms.Methods:Forty-four healthy right-handed subjects were divided at random into a dominant cerebellum group ( n=15), a non-dominant cerebellum group ( n=15) and a control group ( n=14). In the dominant cerebellum group, iTBS was administered to the cerebellum of the dominant hemisphere, and the other hemisphere was given sham stimulation. In the non-dominant cerebellum group, it was the opposite. The dominant cerebellum received the sham stimulation. In the control group both hemispheres received sham stimulation. Before and after the stimulation, single-pulse transcranial magnetic stimulation (TMS) was applied to the representative regions of suprahyoid muscles in bilateral brain and cerebellum to observe changes of the latency and amplitude of motor evoked potentials (MEPs). Results:After the intervention the MEP amplitude of the bilateral swallowing cortex and the stimulated cerebellum had increased in the non-dominant cerebellum group, with increased MEP amplitude only from the stimulated cerebellum of the dominant cerebellum group. Compared with the control group, the non-dominant cerebellum group showed the greatest improvement in MEP amplitude of the stimulated bilateral cerebral cortex and cerebellum. Improvement in the dominant cerebellum group was significantly smaller. However, there were no significant differences in MEP latency or the percentage change in MEP latency from baseline among the three groups.Conclusions:Applying iTBS to either the non-dominant or the dominant cerebellum excites the brain areas related to swallowing, but in different ways.
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AIM: To investigate the effect of c-Myc inhibitor 10058-F4 on human chronic myeloid leukemia ( CML) K562 cells and imatinib-resistant K562/G cells.METHODS: The protein expression of c-Myc was detected by Western blotting .Cell proliferation was evaluated by MTT assay and colony formation assay .PI staining was used to deter-mine the cell cycle distribution .Annexin V-PI staining was applied for apoptosis detection .RESULTS:Imatinib-resistant K562/G cells displayed lower sensitivity to imatinib than K 562 cells with high expression of c-Myc.Treatment with specific c-Myc inhibitor 10058-F4 inhibited the cell proliferation in a dose-and time-dependent manner , and K562/G displayed more sensitivity to 10058-F4 than K562 cells.10058-F4 also induced cell cycle arrest in G 0/G1 phase and induced apoptot-ic cell death in the 2 cells.Importantly, 10058-F4 suppressed the colony formation ability in K 562 and K562/G cells. CONCLUSION:c-Myc is a novel target to overcome imatinib-induced drug resistance , and c-Myc inhibitor provides a new approach in CML therapy .