Cationic switchable lipids: pH-triggered molecular switch for siRNA delivery.

A pH-sensitive molecular switch able to change its conformation upon protonation at endosomal pH values is embedded into the structure of cationic lipidoid materials, thus conferring endosomal escape properties. Involvement of the conformational switch in the endosomal escape process was confirmed and leading material identified was able to induce efficient gene knockdown both in vitro and in vivo. The lipid nanoparticles reported here are promising for therapeutic applications and this work could serve as a template for future design of stimulus-responsive (ionic, redox, light) molecular switch for drug and gene delivery.

[Polymorphous low-grade adenocarcinoma of the accessory salivary glands--a case report]. / Adénocarcinome polymorphe de faible malignité des glandes salivaires accessoires--une observation.

A case of polymorphous low-grade adenocarcinoma of minor salivary gland is reported. This tumor was first described in two clinical case series in 1983. Before that time most of these neoplasms were diagnosed as benign salivary gland neoplasms (pleomorphic adenomas) or salivary malignant conditions (malignant pleomorphic adenomas, adenoid cystic carcinomas, papillary adenocarcinomas and adenocarcinoma not otherwise stated). This neoplasm, with few exceptions, originates in minor salivary gland tissues of the palates or buccal mucosa. It is characteristically slow to enlarge. Clinical reports show the neoplasm present for many years before diagnosis. The tumor have a variety of morphological patterns, a cytological uniformity and an infiltration into adjacent structures. The treatment is a wide local excision. Recurrences and lymph node metastases are rare.