Medisyn Technologies Inc., of Minneapolis, appointed Ian Troup chairman.

Metaphore Pharmaceuticals Inc., of Fort Lee, N.J., appointed Sandra Cartie senior vice president and chief financial officer.

NeoStem, of Agoura Hills, Calif., named Nelson Chao to its medical advisory board.

Orexo AB, of Uppsala, Sweden, appointed Zsolt Lavotha president and CEO.

Oscient Pharmaceuticals Corp., of Waltham, Mass., appointed Glenn Tillotson vice president of scientific and medical relations and John Seay senior director of managed markets.

Otsuka Maryland Research Institute Inc., of Rockville, Md., appointed Ralph Harkins vice president of biometrics.

Prometheus Laboratories Inc., of San Diego, appointed Bruce Neri vice president of diagnostic research and development, and Clyde Shores vice president of marketing.

Rinat Neuroscience Corp., of Palo Alto, Calif., appointed David Pritchard chief business officer and Patricia Ann Walicke vice president of clinical development.

Senomyx Inc., of La Jolla, Calif., appointed Jay Short to its board.

Sirna Therapeutics Inc., of Boulder, Colo., appointed Roberto Guerciolini senior vice president of development and chief medical officer.

Tissera Inc., of Tel Aviv, Israel, appointed Abraham Shaked to its scientific advisory board.

ViRexx Medical Corp., of Edmonton, Alberta, appointed Irwin Griffith vice president of drug development, Douglas Gilpin and Jean Claude Gonneau to its board, Kenneth Stevenson corporate consultant and Howard Appel investor relations consultant.