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BACKGROUND: Recently decellularized nerves with various methods are reported as highly functional nerve grafts for the treatment of nerve defects. OBJECTIVE: To evaluate the efficacy of decellularized allogeneic nerve, compared with oriented chitosan mesh tube, and an autologous nerve. METHODS: Sciatic nerves harvested from Sprague-Dawley (SD) rats were decellularized in combination with Sodium dodecyl sulfate and Triton X-100. A graft into the sciatic nerve in Wistar rats was performed with the decellularized SD rat sciatic nerves or oriented chitosan nonwoven nanofiber mesh tubes (15 mm in length, N = 5 in each group). A portion of sciatic nerve of Wistar rat was cut, reversed and re-sutured in-situ as a control. Nerve functional and histological evaluations were performed 25 weeks postoperatively. RESULTS: It was revealed that functional, electrophysiological and histological recoveries in the decellularized nerve group match those in the autograft group. Recovery of sensory function and nerve maturation in the decellularized nerve group were superior to those in the chitosan mesh tube group. CONCLUSIONS: Nerve regeneration in the decellularized nerves could match that in the autografts and is somehow superior to artificial chitosan mesh tube. Detergents wash of SDS and Triton X-100 could obtain highly functional nerve grafts from allografts. [ABSTRACT FROM AUTHOR]

This study investigated the surface characteristics and antibacterial ability capacity of surface-improved dental glass-ceramics by an electrical polarization process. Commercially available dental glass-ceramic materials were electrically polarized to induce surface charges in a direct current field by heating. The surface morphology, chemical composition, crystal structure, and surface free energy (SFE) were evaluated using scanning electron microscopy, energy dispersive X-ray spectrometry, X-ray diffraction, and water droplet methods, respectively. The antibacterial capacity was assessed by a bacterial adhesion te st using Streptococcus mutans. Although the surface morphology, chemical composition, and crystal structure were not affected by electrical polarization, the polar component and total SFE were enhanced. After 24 h incubation a t 37°C, bacterial adhesion to the polarized samples was inhibited. The electrical polarization method may confer antibacterial properties on prosthetic devices, such as porcelain fused to metal crowns or all ceramic restorations, without any additional bactericidal agents. [ABSTRACT FROM AUTHOR]

The article presents the study on an electromechanical breathing simulator and a respiration sampling device to record and reproduce employee's respiration. It offers information on the breathing simulator which can produce various flow patterns by recording breathing pattern and fixed air flow pattern signals. The results reportedly revealed that the simulator can reproduce workers actual breathing patterns.

This study aimed to investigate the maximum depth imaging and optical properties of the dentin near the pulp by using opticalcoherence tomography (OCT) and to explore the possibility of measuring the remaining dentin thickness (RDT). Human third molarswere used. In experiment 1, the cuspal dentin blocks (0.50-mm to 1.75-mm thickness) were prepared. Each specimen was scannedusing OCT. OCT images could be obtained for all specimens with 1.00-mm or less thicknesses. In experiment 2, dentin-pulp complexslices (0.50-mm and 1.00-mm RDT) were prepared. Each specimen was scanned using OCT and micro-computed tomography, andcompared. The resulting length change rates of OCT images for the 0.50-mm RDTs were significantly lower than those of the 1.00-mm RDTs. Within the limitations of this study, OCT was effective for measuring the 1.00-mm or less RDT and preventing pulpalinjury, while considering the length change rate of OCT image as a variable. [ABSTRACT FROM AUTHOR]

We demonstrated the crystallization of calcium carbonate (CaCO3) on polarized calcite single crystal substrates with three different orientations characterized by the (10.0), (00.1), and (10.4) planes in the presence of polyaspartic acid (PAsp) as an organic additive. The precipitates had a multiple phase structure with thin-film-like and hemispherical forms and were a mixture of calcite, aragonite, and vaterite. The main component of the thin-film-like layers was calcite elongated along the c-axis, regardless of the differently oriented calcite substrates, while the main component of the hemispherical layers was aragonite. The individual crystals of each CaCO3 polymorph shaped the morphology of the mesocrystals. Calcite-aragonite complex films with two distinct structures are similar to those found in pearls and bivalve shells. The combined effect of a surface electric field by virtue of the polarized calcite substrates and PAsp promoted the formation of the thin-film-like layers and moreover, acted remarkably on the negatively charged surface of each oriented calcite substrate. The matching between the β-sheets of PAsp and the calcium-ion arrangement on top of the oriented calcite substrates explained the preferential calcite crystallization in the form of the thin-film-like layers and why calcite precipitates are in the following sequence: (00.1)>(10.4)>(10.0). [ABSTRACT FROM AUTHOR]