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Dexmedetomidine is a highly selective α2-adrenoceptor agonist with sedation, anesthetic sparing, analgesia, sympatholytic, and neuroprotective properties. This study evaluated neuroprotective effects of dexmedetomidine on dopamine neurons correlated to histone acetylation via extracellular signal-regulated protein kinase 1 and 2 (ERK1/2) pathway. Animals were randomly assigned to four groups and treatments were given as onetime doses: dimethyl sulfoxide (DMSO; n = 6), dexmedetomidine 1 mg/kg ( n = 6), 10 mg/kg ( n = 6), and 100 mg/kg ( n = 6). Acetylation histone protein levels and ERK protein levels in rats dopamine neuron from striatum were determined by Western blotting after various doses of dexmedetomidine (1, 10, and 100 mg/kg) treatments. The messenger RNA expression related to signal transduction coupled to 5-hydroxytryptamine receptor (5-HTR) in striatum was assessed by quantitative real-time polymerase chain reaction (qRT-PCR) analysis. Dexmedetomidine administration increased expression of ERK1/2 phosphorylation and histones H3 acetylation. PD098059, an inhibitor of pERK1/2, almost completely blocked dexmedetomidine-induced histones H3 acetylation. In addition, bioinformatics analysis in combination with qRT-PCR demonstrated that dexmedetomidine could regulate the genes that are related to signal transduction coupled to 5-HTR via α2-adrenoceptor. Our results define dexmedetomidine as a modulator of histones H3 acetylation via ERK1/2 signaling pathway in dopamine neuron from striatum, which may provide clues for the mechanism underlying the neuroprotective effects of dexmedetomidine.

Study design: Prospective healthy volunteer study for sensory thresholds. Objectives: The aim of this study was to test sensory thresholds at different sites of the foot to provide a reference for diagnosis and neurologic classification. Setting: A university hospital for the research and clinical practice of rehabilitation. Methods: Thirty healthy volunteers were recruited, and quantitative sensory testing was performed on three sites of the foot (medial malleolus (for the L4 dermatome), dorsum of the foot at the third metatarsal phalangeal joint (for the L5 dermatome) and lateral heel (for the S1 dermatome)). First, cold sense, warm sense, cold pain and hot pain were tested. Second, a monofilament tactility test was performed. Finally, a physical examination for sensation was performed. Results: All of the thresholds for the medial malleolus were significantly different from those for the dorsum of the foot at the third metatarsal phalangeal joint and lateral heel, whereas no significant difference existed between the values for the dorsum of the foot at the third metatarsal phalangeal joint and lateral heel. Conclusion: The sensory threshold of the human medial malleolus may be significantly different from those of adjacent sites of the foot. Thus, the results obtained from physical examination of sensory thresholds of the medial malleolus should be used modestly as a reference, but should not be used for diagnostic or classification purposes.

The nucleon correlation including the short range correlation and the nuclear core polarization has been investigated by using a diagrammatic effective operator approach. The calculated results show that the contributions of the nucleon correlation to the the 0[nu][beta][beta] decay of [sup 76]Ge and [sup 82]Se are quite important, especially in the heavy-neutrino case.

The nuclear matrix elements of Ge-76 and Se-82 are studied by using the shell model wave functions in a model-space approximation. The influences of both nuclear short-range correlation and finite nucleon size on the transition matrix elements are also taken into account. The limits of Majorana neutrino mass and mixing parameter of right-handed current have been deduced by fitting the experimental values of 0nubetabeta decay lifetimes of Ge-76 and Se-82.