Enantioselectivity in the (salen)Mn-catalyzed asymmetric epoxidation reaction correlates directly with the electronic properties of the ligand substituents, with complexes bearing electron-donating substituents affording highest ee's. Several lines of evidence point to a single factorcontrol of the position of the transition state along the reaction coordinateas being responsible for the electronic effects on enantioselectivity. Analysis of the epoxidation of cis-β-deuteriostyrene reveals that electron-rich catalysts display a more pronounced secondary inverse isotope effect than electron-deficient catalysts. A strong correlation between ΔΔH ⧧ and the electronic character of the catalyst is also observed. The conclusion that enantioselectivity is tied to the position of a transition state along the reaction coordinate may hold general implications for the design of asymmetric catalysts, particularly those that effect reactions without substrate precoordination.

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ABSTRACT. Infectious tracheobronchitis (ITB), also known as the kennel cough, is a respiratory syndrome of dogs and usually appears to be contagious among dogs housed in groups. Etiologic agent of ITB is multiple and sometimes complex. In the present study, 68 household dogs showing clinical signs of respiratory infection were examined, and 20 dogs (29.4%) were found to be positive for either of following agents. Bordetella bronchiseptica (B.b.) was most frequently detected from nasal and oropharynx sites of 7 dogs (10.3%). Among the viruses examined, canine parainfluenza virus (CPIV) was detected with the highest frequency (7.4%). Other pathogens included in the order of frequency group 1 canine coronavirus (4.4%), canine adenovirus type 2 (2.9%), group 2 canine respiratory coronavirus (1.5%), and canine distemper virus (1.5%). Only 2 cases showed mixed infections. Neither influenza A virus nor canine bocavirus (minute virus of canines) was found in any dogs examined. These results indicate that both B.b. and CPIV are likely to be the principal etiologic agents of canine ITB in Japan, and they may be considered as the target for prophylaxis by vaccination. KEY WORDS: Bordetella bronchiseptica, canine parainfluenza virus, canine respiratory coronavirus, infectious tracheobronchitis, kennel cough.

Abstract— Two Pugs and two Miniature Schnauzers with multiple pigmented epidermal nevi were investigated. The four dogs had pigmented cutaneous maculae and plaques. Histopathological evaluation showed papillated or digitated epidermal hyperplasia with hypermelanosis and giant keratohyalin granules in the stratum granulosum. Immunohistochemical staining revealed papillomavirus group‐specific antigen in the skin specimens from all four dogs. Electron microscopic study of the specimens from two dogs revealed numerous round viral particles within the nuclei of the keratinocytes in the upper stratum granulosum. It was suspected that papillomavirus was the etiologic agent of the lesions, and that Pugs and Miniature Schnauzers might be predisposed to infection. These findings indicate this canine dermatosis resembles epidermodysplasia verruciformis (EV) of humans, a rare chronic disease caused by human papillomavirus. The potential for transformation of the lesions to squamous cell carcinoma is also suspected and discussed. Résumé— Deux Carlins et deux Schnauzers nains présentant de multiples naevi épidermiques pigmentés sont examinés. Les quatre chiens présentent des macules et des plaques pigmentées. Les lésions histopathologiques montrent une hyperplasie épidermique papillaire ou digitée avec une hypermélanose et la présence de grains de kératohyaline dans le stratum corneum. Les colorations immunohistochimiques révèlent des antigènes spécifiques du groupe des papillomas virus dans les biopsies des quatre chiens. L'étude ultrastructurale à partir des biopsies de deux chiens montrent de nombreuses particules virales rondes dans les noyaux des kératinocytes des couches supérieures du stratum granulosum. II a été suspecté que le papilloma virus était l'agent causal des lésions et que les Carlins et les Schnauzers nains pouvaient être prédisposés à cette infection. Ces éléments font que cette dermatose observée chez le chien ressemble à l'épidermodysplasie verruciforme de l'homme, une dermatose chronique rare causée par un papilloma virus humain. La potentialité de transformation des lésions en épithélioma spinocellulaire est aussi suspectée et discutée. [Nagata, M., Nanko, H., Moriyama, A., Washizu, T., Ishida, T. Pigmented plaques associated with papilloma virus infection in dogs: Is this epidermodysplasia verruciformis? (Plaques hyperpigmentées associées à une infection à papilloma virus chez le chien: est‐ce épidermodysplasie verruciforme?). Resumen— Se investigó dos perros de raza Pug y dos de raza Schnauzer Miniatura con múltiples nevos epidérmicos pigmentados. Los cuatro perros presentaban máculas y placas cutáneas pigmentadas. El estudio histológico mostró hiperplasia epitelial con papilas y digitaciones, así como hipermelanosis y gránules de queratohialina gigantes en el estrato granuloso. Las tinciones immunohistoquimicas detectaron antígeno grupo‐específico de papilomavirus en las muestras de los cuatro animales. Mediante estudios de microscopía electrónica en muestras de dos de los perros se observaron numero...

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