Développement d'un système d'alerte précoce basé sur des bioessais pour la gestion des risques liés aux sites d'enfouissement au Japon

The objections of residents, who suspect that solid waste treatment and disposal facilities emit hazardous substances into surrounding areas, make it difficult to construct and operate these facilities all over Japan. We discuss herein some issues and perspectives regarding the application of toxicity tests to solid waste management, especially to the monitoring of leachate from waste disposal sites. We investigated various toxic potencies and attempted simple scoring of the results for risk management and risk communication to citizens. The data of control experiments and chemical analysis showed that the toxicities observed in leachates weren’t derived from salinity and heavy metals alone. Our scoring results demonstrate the feasibility of a biotest battery for practical use.Au Japon, l’opinion publique est devenue très méfiante vis-à-vis des installations de gestion et de traitement des déchets, en particulier les centres de stockage de déchets ultimes. Le projet présenté ici vise à développer une nouvelle méthodologie, reposant sur des bioessais de toxicité et qui permettrait de surveiller les risques d’impacts liés au fonctionnement de ces sites, et principalement ceux liés aux lixiviats. Une batterie de bioessais a été proposée et testée avec une méthode des scores qui permet de caractériser les effets toxicologiques des lixiviats bruts et traités. Les résultats obtenus montrent que les effets toxiques révélés ne sont pas systématiquement corrélés à la salinité et au contenu en métaux lourds des lixiviats. En complément des analyses chimiques, une méthodologie basée sur une batterie de bioessais peut alors être proposée comme outil fiable et économique de gestion des centres de stockage de déchets ultimes

Association between head-and-neck cancers and active and passive cigarette smoking

Although there have been many reports on the toxicity of tobacco smoke, fewer studies have reported the relationship between the smoke and carcinogenesis of head-and-neck cancers. It is assumed that direct stimulations due to to-bacco smoke, such as chemical and mechanical stimulations, strongly influence the epithelium of the nasal cavity, paranasal sinuses, pharynx, and larynx. We investigated the influence of ac-tive and passive cigarette smoking on head-and-neck cancers. The subjects were 283 head-and-neck cancer patients examined at the otolaryn-gology department of Showa University North-ern Yokohama Hospital in a 9-year and 2-mont

Ion Transportation by Prussian Blue Nanoparticles Embedded in a Giant Liposome

A new type of artificial giant liposome incorporating ion transport channels and using nanoparticles of metal organic frameworks was demonstrated. The micropores of Prussian blue nanoparticles served as ion transport channels between the outer and inner phases of liposomes

The Efficacy of Radiotherapy without Surgery for External Auditory Canal Squamous Cell Carcinoma

External auditory canal (EAC) cancer is a rare disease for which there are no adequate evidence-based treatment strategies. Radiotherapy is often used as the initial treatment to preserve the organ. This study aimed to elucidate the efficacy of radiotherapy for EAC squamous cell carcinoma (SCC). Patients with T1 disease were treated with radiotherapy alone. Patients with T2–4 disease were treated with chemoradiotherapy. The median follow-up period was 30.4 months. The 3-year local control (LC) rate for all patients was 51%, the disease-free survival (DFS) rate was 44%, and the overall survival (OS) rate was 73%. For T1–3 disease, the 3-year LC rate was 74%, DFS was 62%, and OS was 89%. However, for T4 disease, the 3-year LC rate was 17%, DFS was 17%, and OS was 50%. In a univariate analysis, only the T-category was a significant factor for LC and DFS (p = 0.006 and 0.02, respectively). All local recurrences were within the high-dose irradiated area. The results of this study suggest chemoradiotherapy can be an alternative to a combination of surgery and postoperative radiation for T1–3 SCC of the EAC. However, the efficacy of chemoradiotherapy in T4 cases was inadequate