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Purpose: To evaluate the effect of mechanical epithelial separation with an epikeratome on the histologic ultrastructure of epithelial flaps and stromal beds from human corneas. Setting: Departments of Ophthalmology, Osaka University Medical School, Osaka, and Tohoku University School of Medicine, Sendai, and Institute of Advanced Biomedical Engineering and Science and Medical Research Institute, Tokyo Women''s Medical University, Tokyo, Japan. Methods: Eye-bank eyes were deepithelialized using an Epi-K epikeratome. Epithelial flaps and stromal beds were assessed by light and electron microscopy. Immunofluorescence staining for types IV and VII collagens, integrins α6 and β4, and laminin 5 was also performed. Results: Four eyes were evaluated. On scanning electron microscopy, the cleavage planes of epithelial flaps and stromal beds were relatively smooth. On transmission electron microscopy, epithelial flaps were separated partially within the lamina fibroreticularis and partially within the lamina lucida. Immunofluorescence showed positive staining for type VII collagen and discontinuous staining for type IV collagen in stromal beds. Discontinuous linear staining for types IV and VII collagens was observed in epithelial flaps. Staining for integrins α6 and β4 was positive in some regions and discontinuous in other regions of epithelial flaps. In stromal beds, integrins α6 and β4 had a patchy expression pattern. Staining for laminin 5 was intermittently positive along the basal side of epithelial flaps and stromal beds. Conclusions: Epithelial flaps created with an epikeratome were mechanically separated partly within the lamina fibroreticularis and partly within the lamina lucida. Stromal beds had relatively smooth surfaces with no obvious trauma to Bowman layer. [Copyright &y& Elsevier]

Summary: Studies were conducted on the ecology of potentially pathogenic Vibrio parahaemolyticus in three coastal areas of Kii Channel, Tokushima, Japan. Seawater and seaweed samples were collected seasonally between June 2003 and May 2004. Total and toxigenic strains of V. parahaemolyticus were isolated using most probable number culture and colony blot hybridization. Toxigenic strains were serotyped and further characterized by random amplified polymorphic DNA (RAPD) and ribotyping. Six thousand strains of V. parahaemolyticus were isolated and 18 were found positive for tdh. V. parahaemolyticus were detected in all samples during summer and autumn, and from some samples during winter and spring. Among the toxigenic strains seven serotypes, five ribotypes and RAPD patterns were observed. Seven strains belonged to O3:K6 clone with identical ribotypes and RAPD patterns to that of a pandemic reference strain. The presence of toxigenic V. parahaemolyticus with pandemic potential might indicate a human health risk due to consumption of marine food sources. [Copyright &y& Elsevier]

Legislation for expedited-approval pathways and programmes for drugs, biologics or medical devices has been enacted for rapid commercialization of innovative products in the United States of America (USA) and the European Union (EU). However, less innovative products are increasingly benefitting from these expedited-approval pathways, and obligations to collect and report post-marketing data on approved products are being bypassed frequently. The Japanese government recently enacted legislation for a new conditional and time-limited approval pathway dedicated to regenerative medicine products. The current study examines this new legislation and compares it with existing US and EU regulatory frameworks, with a particular focus on how it addresses the limitations of existing systems. Regulations, guidance documents and approval information were gathered from the websites of the respective authorities in the USA, the EU and Japan, and the systems were categorized through qualitative analysis. The pathways and programmes from each region were categorized into four groups, based on the requirement of pre- or post-marketing clinical data. Expedited-approval pathways in the USA and the EU provide similar qualification criteria, such as severity of target disease; however, such criteria are not specified for the new pathway in Japan. Only the Japanese pathway stipulates a time limitation on exceptional approval, requiring post-marketing study for conditional and time-limited products. Continuous improvement is necessary to solve previously addressed issues within the expedited-approval pathways and programmes and to ensure that innovative medical products are rigourously screened, but also readily available to patients in need. The time limitation of conditional approval could be a potential solution to some of these problems. Copyright © 2017 The Authors. Tissue Engineering Regenerative Medicine published by John Wiley & Sons, Ltd., (Copyright © 2017 The Authors. Tissue Engineering Regenerative Medicine published by John Wiley & Sons, Ltd.)

Background & Aims: The use of esophageal endoscopic submucosal dissection (ESD) to remove superficial esophageal neoplasms is gradually becoming more common in Japan. However, large-scale esophageal ESD often requires subsequent multiple balloon dilations to prevent postoperative esophageal stricture. We investigated the safety and efficacy of endoscopic transplantation of tissue-engineered autologous oral mucosal epithelial cell sheets in preventing formation of strictures after ESD., Methods: We performed an open-label, single-arm, single-institute study. We collected specimens of oral mucosal tissue from 9 patients with superficial esophageal neoplasms. Epithelial cell sheets were fabricated ex vivo by culturing isolated cells for 16 days on temperature-responsive cell culture surfaces. After a reduction in temperature, these sheets were endoscopically transplanted directly to the ulcer surfaces of patients who had just undergone ESD. All patients were monitored by endoscopy once a week until epithelialization was complete., Results: Autologous cell sheets were successfully transplanted to ulcer surfaces using an endoscope. Complete re-epithelialization occurred within a median time of 3.5 weeks. No patients experienced dysphagia, stricture, or other complications following the procedure, except for one patient who had a full circumferential ulceration that expanded to the esophagogastric junction., Conclusions: Sutureless, endoscopic transplantation of carrier-free cell sheets composed of autologous oral mucosal epithelial cells safely and effectively promotes re-epithelialization of the esophagus after ESD. Patients in this study did not experience any serious complications. This procedure might be used to prevent stricture formation following ESD and improve patients' quality of life. Further study will be needed to show that stricture formation can be prevented., (Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.)