Neuroscience
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Glucocorticoids (GCs) are widely used as powerful anti-inflammatory and immunosuppressive therapeutics in multiple pathological conditions. However, compelling evidence indicates that they might promote neurodegeneration by altering mitochondrial homeostatic processes. ⋯ In this report, we have compared the neurotoxicity induced by dexamethasone, prednisolone, betamethasone, and hydrocortisone in cultured neuroblastoma cells, through the analysis of several parameters such as cell viability, ER stress, oxidative stress, and mitochondrial fusion and fission markers. Interestingly, we have found that synthetic glucocorticoids may impact neuronal viability by affecting different cellular responses, suggesting that their therapeutic use should be consciously decided after careful consideration of benefits and detrimental effects.
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Transcranial magnetic stimulation (TMS) combined with electroencephalography (EEG), TMS-EEG, is a useful neuroscientific tool for the assessment of neurophysiology in the human cerebral cortex. Theoretically, TMS-EEG data is expected to have a better data quality as the number of stimulation pulses increases. However, since TMS-EEG testing is a modality that is examined on human subjects, the burden on the subject and tolerability of the test must also be carefully considered. ⋯ This is the first substantial study to examine the appropriate number of stimulus pulses that are reasonable and feasible for TMS-EEG testing of the DLPFC.
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This study evaluated the isolated and combined effects of fear and PPS paradigms on SBR. ⋯ Fear suppressed SBR, but fear increased SBR when a threat stimulus was present. The findings were unrelated to habituation or attention, indicating cortical-amygdala-bulbar connections.
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In mammalian central neurons AMPARs are clustered at glutamatergic synapses where they mediate fast excitatory transmission. In addition to four pore-forming subunits (GluA1-4), AMPARs contain auxiliary transmembrane AMPAR regulatory proteins (γ2, γ3, γ4, γ5, γ7 or γ8) whose incorporation can vary between neuron types, brain regions, and stages of development. As well as modulating the functional properties of AMPARs, these auxiliary subunits play a central role in AMPAR trafficking. ⋯ In living neurons, fluorescent α-Btx-labelled γ2 associates with AMPAR clusters at synapses. As a proof-of-principle, we employed our method to compare the surface trafficking of γ2 and γ7 in cerebellar stellate neurons. Our approach provides a simple way to visualize TARPs within AMPARs in living cells.
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Aftereffects of non-invasive brain stimulation techniques may be brain state-dependent. Either continuous theta-burst stimulation (cTBS) as transcranial static magnetic field stimulation (tSMS) reduce cortical excitability. Our objective was to explore the aftereffects of tSMS on a M1 previously stimulated with cTBS. ⋯ The interaction of tSMS with cTBS seems not to take place at inhibitory cortical interneurons tested by LICI, since LICI was not differently affected after real and sham tSMS. Our results indicate the existence of a process of homeostatic plasticity when tSMS is applied after cTBS. This work suggests that tSMS aftereffects arise at the synaptic level and supports further investigation into tSMS as a useful tool to restore pathological conditions with altered cortical excitability.