ABSTRACT
Objective:To evaluate the effect of dexmedetomidine on the excitability of fast-spiking interneurons in the primary somatosensory cortex of mouse brain.Methods:Eleven healthy C57BL/6 mice of either sex, at postnatal days 15-21, were used.The acute brain slices of primary somatosensory cortex were prepared and incubated in artificial cerebrospinal fluid.The whole-cell patch-clamp was established on fast-spiking interneurons and excitatory neurons in primary somatosensory cortex layer 4 separately.The membrane potential and action potential threshold from fast-spiking interneurons and spontaneous inhibitory postsynaptic currents from excitatory neurons were recorded before application of dexmedetomidine (10 μmol/L)and at 5 min after application of dexmedetomidine.Results:Compared with that before application of dexmedetomidine, no significant change was found in the membrane potential and action potential threshold of fast-spiking interneurons and frequency and amplitude of spontaneous inhibitory postsynaptic currents at 5 min after application of dexmedetomidine( P>0.05). Conclusion:The analgesic mechanism of dexmedetomidine may not be related to the excitability of fast-spiking interneurons in the primary somatosensory cortex of the mouse brain.
ABSTRACT
Objective To evaluate the diagnostic value of 99Tcm-MIBI SPECT/CT imaging and 99Tcm-MIBI planar imaging semi-quantitative analysis in primary hyperparathyroidism (PHPT).Methods A total of 89 patients were enrolled into this retrospective study.The diagnostic efficiencies of 99Tcm-MIBI SPECT/CT were compared with 9Tcm-MIBI planar scintigraphy and ultrasound,while the surgical pathology and the clinical follow-up results were considered as the standard.The region of interest extraction technique was used to measure and calculate the tumour to normal tissue ratios (T/NT) in the early and delayed phase of the planar scintigraphy,and the correlation between pathological type,PTH concentration and T/NT ratios was analyzed.Results The sensitivities and specificities of SPECT/CT,99Tcm-MIBI planar scintigraphy and ultrasound were 98.08％,88.46％,78.43％;82.93％,82.93％,58.82％ respectively.There were statistically significant correlations between the pathological type and PTH concentration,early phase T/NT and delayed phase T/NT,and the correlation coefficients r were 0.741,0.642 and 0.729,respectively.Conclusions 99Tcm-MIBI SPECT/CT imaging is an effective method for diagnosis of PHPT,with higher clinical application value than 99Tcm-MIBI planar scintigraphy and ultrasound.The semi-quantitative analysis of 99Tcm-MIBI planar scintigraphy provides a new method for the differential diagnosis of PHPT.