Role of 5-HT2A Receptor in Modulating Glutamatergic Activity in the Ventrolateral Orbital Cortex: Implication in Trigeminal Neuralgia.

5-HT2A receptors (5-HT2ARs) are widely expressed in the central nervous system, including in the ventrolateral orbital cortex (VLO). The VLO is an important cortical component for pain processing. Brain 5-HT2ARs are implicated in both pro- and anti- nociceptive functions. However, the roles of 5-HT2ARs in the VLO in trigeminal neuralgia and neuronal synaptic function remain to be understood. We used chronic constriction injury of infraorbital nerve (IoN-CCI) model and shRNA mediated gene knockdown in mice to investigate the role of 5-HT2ARs in the VLO in trigeminal neuralgia. We found that knockdown of 5-HT2ARs in the VLO aggravated spontaneous pain and mechanical allodynia in mice after IoN-CCI. At the synaptic level, decreasing 5-HT2AR expression by shRNA or inhibition of 5-HT2AR activity by its antagonist ketanserin decreased the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs) of the neurons in the VLO, whereas 5-HT2AR partial agonist 2,5-Dimethoxy-4-iodoamphetamine (DOI) enhanced sEPSCs of the neurons in the VLO. In summary, 5-HT2ARs in the VLO modulate the trigeminal pain by regulating neuronal glutamatergic activity.

Effect of dentin exposure on the shear bond strength of cast porcelain veneers / 口腔疾病防治

Objective@#To explore the best indication for veneers and to improve the repair success rate by investigating the effects of different types of dentin exposure on the shear bond strength of cast porcelain veneers with two new veneer bonding systems.@*Methods@#Bonding interfaces with 0%, 25%, 50%, 75% and 100% dentin exposure were designed and fabricated. The bonding interfaces were divided into groups A, B, C, D and E. Sixty 4-mm x 4-mm x 2-mm (length x width x thickness) ceramic specimens were bonded by using two bonding systems, The VN-A, VN-B, VN-C, VN-D and VN-E groups were bonded with Variolink bonding system, and the PF-A, PF-B, PF-C, PF-D and PF-E were bonded with Panavia F bonding system (six specimens per group). The bonded specimens were stored in a distilled water bath at (37 + 1)℃ for 24 hours. The fracture load was tested by a universal testing machine, and the fracture type was observed by scanning electron microscopy.@*Results @#The VN-A (25.14 ± 3.40 MPa), VN-B (22.54 ± 4.48 MPa), VN-C (19.59 ± 2.21 MPa), PF-A (20.61 ± 2.42 MPa), PF-B (18.08 ± 4.11 MPa), PF-C (17.06 ± 2.29 MPa) groups’ shear bond strengths were above 17 MPa. The VN-A group had the highest shear bond strength value. There was no statistically significant difference in bond strength between the VN-A group and the VN-B and VN-C groups (P > 0.05) or the PF-A and PF-B groups (P > 0.05); however, the differences between VN-A and the VN-D and VN-E groups (P < 0.05) and between PF-A and the PF-C and PF-D and PF-E groups (P < 0.05) were statistically significant. The differences between the VN-A group and PF-A group (P < 0.05) were statistically significant. The fracture modes of the VN-A, PF-A, VN-B, PF-B, and VN-C groups mainly included resin cement cohesive failure and mixed failure; the VN-D, VN-E, PF-C, PF-D and PF-E groups were dominated by interface failure and mixed failure.@*Conclusion@#When the dentin exposure is greater than 50%, the shear bond strength value of the veneer was significantly affected. To obtain a better clinical effect, the dentin exposure rate should be less than 25%.

Use of 1-alkyl-3-methylimidazolium-based ionic liquids as background electrolytes in capillary electrophoresis for the analysis of inorganic anions.

Separation of inorganic anions in CE is often a challenging task because the electrophoretic mobilities of inorganic anions are comparable to or even greater than the EOF mobility. In this study, we present the use of ionic liquids (ILs) as background electrolytes (BGEs) in CE of inorganic anions. The 1-alkyl-3-methylimidazolium-based ILs as BGEs dynamically coated the capillary wall and induced a reversed EOF. This allowed the anions to comigrate with the EOF and yielded a rapid separation. Increasing the alkyl chain length of the ILs and BGE concentration can significantly improve the separation resolution. With 40 mM 1-butyl-3-methylimidazolium tetrafluoroborate as BGE, good separations of five model anions (Br-, I-, NO2(-), NO3(-), and SCN-) were achieved in a range of buffer pH values. The separation efficiency was as high as 34 600-155 000, and the RSDs of the migration times were less than 0.8% (n = 5).