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Both Gram-positive and Gram-negative bacteria release nanosized extracellular vesicles called membrane vesicles (MVs, 20−400 nm), which have great potential in various biomedical applications due to their abilities to deliver effector molecules and induce therapeutic responses. To fully utilize bacterial MVs for therapeutic purposes, regulated and enhanced production of MVs would be highly advantageous. In this study, we developed a universal method to enhance MV yields in both G+/G− bacteria through an autonomous controlled peptidoglycan hydrolase (PGase) expression system. A significant increase (9.37-fold) of MV concentration was observed in engineered E. coli Nissle 1917 compared to the wild-type. With the help of this autonomous system, for the first time we experimentally confirmed horizontal gene transfer and nutrient acquisition in a cocultured bacterial consortium. Furthermore, the engineered probiotic E. coli strains with high yield of MVs showed higher activation of the innate immune responses in human embryonic kidney 293T (HEK293T) and human colorectal carcinoma cells (HCT116), thereby demonstrating the great potential of engineering probiotics in immunology and further living therapeutics in humans.

Functional Neuroanatomy, an interactive electronic neuroanatomical atlas, was designed for first year medical students. Medical students have much to learn in a limited time; therefore a major goal in the atlas design was that it facilitate rapid, accurate information retrieval. To assess this feature, we designed a testing scenario in which students who had never taken a neuroanatomy course were asked to complete two equivalent tests, one using the electronic atlas and one using a comparable hard copy atlas, in a limited period of time. The tests were too long to be completed in the time allotted, so test scores were measures of how quickly correct information could be retrieved from each source. Statistical analysis of the data showed that the tests were of equal difficulty and that accurate information retrieval was significantly faster using the electronic atlas when compared with the hard copy atlas (P < 0.0001). Post-test focus groups (n = 4) allowed us to infer that the following design features contributed to rapid information access: the number of structures in the database was limited to those that are relevant to a practicing physician; all of the program modules were presented in both text and image form on the index screen, which doubled as a site map; pages were layered electronically such that information was hidden until requested, structures available on each page were listed alphabetically and could be accessed by clicking on their name; and an illustrated glossary was provided and equipped with a search engine.

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