of (benzylidene-hydrazono)-1,4dihydropyridines with β-amyloid, acetylcholine, and butyrylcholine esterases. Bioorg. Med. Chem. 18, 2049 -2059 . Angelisová, P., Drbal, K., Horejsí, V., and Cerný, J. (1999 . Association of CD10/neutral endopeptidase 24.11 with membrane microdomains rich in glycosylphosphatidylinositolanchored proteins and Lyn kinase. Blood 93, 1437-1439. Araki, W., Kitaguchi, N., Tokushima, Y., Ishii, K., Aratake, H., Shimohama, S., Nakamura, S., and Kimura, J. (1991) . Trophic effect of β-amyloid www.frontiersin.org West Nile Virus Infection in Killer Whale, Texas, USA, 2007 In 2007, nonsuppurative encephalitis was identified in a killer whale at a Texas, USA, marine park. Panviral DNA microarray of brain tissue suggested West Nile virus (WNV); WNV was confirmed by reverse transcription PCR and sequencing. Immunohistochemistry demonstrated WNV antigen within neurons. WNV should be considered in cases of encephalitis in cetaceans. virus of the genus Flavivirus that is transmitted by mosquitoes. In humans and animals, WNV has been associated with a spectrum of clinical conditions from asymptomatic infections to sudden death. These have been identifi ed in a variety of animal species. Among marine mammals, WNV infection has been reported in a harbor seal (Phoca vitulina) (1) . We describe WNV infection in a killer whale (Orcinus orca) and seroprevalence in conspecifi c cohort and noncohort groups.