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Background: It is important to know the mechanisms underlying pain abnormalities associated with inferior alveolar nerve (IAN) regeneration in order to develop the appropriate treatment for orofacial neuropathic pain patients. However, peripheral mechanisms underlying orofacial pain abnormalities following IAN regeneration are not fully understood.Methods: Head withdrawal threshold (HWT), jaw opening reflex (JOR) thresholds, single-fibre recordings of the regenerated mental nerve (MN) fibres, calcitonin gene-related peptide (CGRP), isolectin B4 (IB4), peripherin, neurofilament-200 (NF-200) and transient receptor potential vanilloid 1 (TRPV1) expression in trigeminal ganglion (TG) cells, and electron microscopic (EM) observations of the regenerated MN fibres were studied in MN- and IAN-transected (M-IANX) rats.Results: HWT to mechanical or heat stimulation of the mental skin was significantly lower in M-IANX rats compared with sham rats. Mean conduction velocity of action potentials recorded from MN fibres (n = 124) was significantly slower in M-IANX rats compared with sham rats. The percentage of Fluoro-Gold (FG)-labelled CGRP-, peripherin- or TRPV1-immunoreactive (IR) cells was significantly larger in M-IANX rats compared with that of sham rats, whereas that of FG-labelled IB4- and NF-200-IR cells was significantly smaller in M-IANX rats compared with sham rats. Large-sized myelinated nerve fibres were rarely observed in M-IANX rats, whereas large-sized unmyelinated nerve fibres were frequently observed and were aggregated in the bundles at the distal portion of regenerated axons.Conclusions: These findings suggest that the demyelination of MN fibres following regeneration may be involved in peripheral sensitization, resulting in the orofacial neuropathic pain associated with trigeminal nerve injury. [ABSTRACT FROM AUTHOR]

Background Although the efficacy of peripherally administered opioid has been demonstrated in preclinical and clinical studies, the underlying mechanisms of its anti-hyperalgesic effects are poorly understood. G protein-coupled inwardly rectifying potassium ( GIRK) channels are linked to opioid receptors in the brain. However, the role of peripheral GIRK channels in analgesia induced by peripherally administered opioid, especially in trigeminal system, is not clear. Methods Expression of GIRK subunits in rat trigeminal ganglia ( TG) was examined with reverse transcription-polymerase chain reaction, Western blot and immunohistochemistry. Chemical profiles of GIRK-expressing neurons in TG were further characterized. Behavioural and Fos experiments were performed to examine the functional involvement of GIRK channels in δ-opioid receptor ( DOR)-mediated anti-hyperalgesia under an acute myositis condition. Results TG expressed mRNA and proteins for GIRK1 and GIRK2 subunits. Majority of GIRK1- and GIRK2-expressing neurons were non-peptidergic afferents. Inhibition of peripheral GIRK using Tertiapin- Q ( TPQ) attenuated antinociceptive effects of peripherally administered DOR agonist, [D-Pen2, D-Pen6]-enkephalin ( DPDPE), on mechanical hypersensitivity in masseter muscle. Furthermore, TPQ attenuated the suppressive effects of peripheral DPDPE on neuronal activation in the subnucleus caudalis of the trigeminal nucleus ( Vc) following masseteric injection of capsaicin. Conclusions Our data indicate that peripheral DOR agonist-induced suppression of mechanical hypersensitivity in the masseter muscle involves the activity of peripheral GIRK channels. These results could provide a rationale for developing a novel therapeutic approach using peripheral GIRK channel openers to mimic or supplement the effects of peripheral opioid agonist. [ABSTRACT FROM AUTHOR]

Spherical LiNi1/2Mn1/2O2 powders were synthesized from LiOH . H2O and coprecipitated metal hydroxide, (Ni1/2Mn1/2)(OH)2. The average particle size of the powders was about 10µm and the size distribution was quite narrow due to the homogeneity of the metal hydroxide, (Ni1/2Mn1/2)(OH)2. The tap-density of the LiNi1/2Mn1/2O2 powders was approximately 2.2 g cm-3, which is comparable to the tap-density of commercial LiCoO2. The LiNi1/2Mn1/2 O2electrode delivered a discharge capacity of 152, 163, 183, and 189 mA h g-1 in the voltage ranges of 2.8-4.3, 2.8-4.4, 2.8-4.5, and 2.8-4.6 V, respectively, with good cyclability. Furthermore, Al(OH)3-coated LiNi1/2Mn1/2O2exhibited excellent cycling behavior and rate capability compared to the pristine electrode. [ABSTRACT FROM AUTHOR]

Abstract: Spherical Li[Ni0.475Co0.05Mn0.475]O2 powders were synthesized from LiOH·H2O and coprecipitated spherical metal carbonate, (Ni0.475Co0.05Mn0.475)CO3. Due to the homogeneity and spherical morphology of the metal carbonate, the final product, Li[Ni0.475Co0.05Mn0.475]O2, was also significantly uniform with a narrow particle size distribution and an average particle of about 15 μm. TEM observation showed that each spherical particle consisted of finer primary particles whose size ranged from 200 nm to 300 nm. The Li[Ni0.475Co0.05Mn0.475]O2 electrode delivered an initial discharge capacity of approximately 160 mAh g−1 showing no capacity loss up to 50 cycles with excellent rate capability. [Copyright &y& Elsevier]

Abstract: Spherical Li[Ni1/3Co1/3Mn1/3]O2 powders were synthesized from LiOH·H2O and coprecipitated spherical metal hydroxide, (Ni1/3Mn1/3Co1/3)(OH)2 and coated with Al(OH)3. The Al(OH)3-coated Li[Ni1/3Co1/3Mn1/3]O2 showed a capacity retention of 80% at 320mAg−1 (2C-rate) based on 20mAg−1 (0.1C-rate), while the pristine Li[Ni1/3Co1/3Mn1/3]O2 delivered only 45% at the same current density. Also, unlike pristine Li[Ni1/3Co1/3Mn1/3]O2, the Al(OH)3-coated Li[Ni1/3Co1/3Mn1/3]O2 cathode exhibits excellent rate capability and good thermal stability. [Copyright &y& Elsevier]