Two-Ply Carbon Nanotube Fiber-Typed Enzymatic Biofuel Cell Implanted in Mice.

Implantable devices have emerged as a promising industry. It is inevitable that these devices will require a power source to operate in vivo. Thus, to power implantable medical devices, biofuel cells (BFCs) that generate electricity using glucose without an external power supply have been considered. Although implantable BFCs have been developed for application in vivo, they are limited by their bulky electrodes and low power density. In the present study, we attempted to apply to living mice an implantable enzymatic BFC (EBFC) that was previously reported to be a high-power EBFC comprising carbon nanotube yarn electrodes. To improve their mechanical properties and for convenient implantation, the electrodes were coated with Nafion and twisted into a micro-sized, two-ply, one-body system. When the two-ply EBFC system was implanted in the abdominal cavity of mice, it provided a high-power density of 0.3 mW/cm2. The two-ply EBFC system was injected through a needle using a syringe without surgery and the inflammatory response in vivo initially induced by the injection of the EBFC system was attenuated after 7 days, indicating the biocompatibility of the system in vivo.

Surgical outcome of mitomycin C-soaked collagen matrix implant in trabeculectomy.

PURPOSE: To assess the surgical outcomes and wound healing reaction of a filtering bleb after trabeculectomy using mitomycin C-soaked biodegradable collagen matrix (ologen). METHODS: Thirty eyes, in which the intraocular pressure (IOP) could not be controlled within the proper range by medication or laser treatment, were targeted in this study. After trabeculectomy with mitomycin C (0.2 mg/mL, 0.1 mL)-soaked ologen, surgical outcomes were assessed by evaluating bleb morphology by the Moorfield bleb grading system, as well as internal reflectivity and wound healing response of the bleb using a slit lamp and ultrasound biomicroscopy. The follow-up period continued for 12 months after surgery. RESULTS: Twelve months after surgery, 12/30 (40.0%) eyes were considered complete successes and 24/30 (80%) eyes as qualified successes. This rate is similar to the rate of our conventional trabeculectomy. The encapsulated bleb was the most frequent complication (9 eyes) and generally occurred at approximately 2 weeks after surgery. No avascular blebs were observed at final follow-up. CONCLUSIONS: Trabeculectomy with mitomycin C-soaked ologen do not seem to exert any synergistic effect with antimetabolites in terms of a reduction in IOP. However, the mitomycin C-soaked collagen matrix implant used in trabeculectomy resulted in comparatively stable IOP and did not aggravate wound healing or scar formation. Encapsulated blebs were generated at a more rapid pace in larger amounts compared with conventional trabeculectomy. The management of encapsulated blebs may be crucial to improving the success rate of surgery.