The in vivo pathogenicity of canine parvovirus (CPV) type 2c (strain V203) and of CPV type 2a (strain V154) against cats was investigated. Our results indicate that both types of CPV have the potential to induce disease in cats.Canine parvovirus (CPV) and feline panleukopenia virus (FPLV) are members of the feline parvovirus (FPV) subgroup and are classified as autonomous parvoviruses of the family Parvoviridae (23). CPV type 2 (CPV-2) was first observed in dogs in 1978, and this virus subsequently became globally distributed such that it is now endemic in populations of domestic and wild canids (16,22). The origin of CPV-2 has not yet been identified, although various hypotheses explaining its derivation and sudden emergence have been proposed. The most widely accepted hypothesis for its emergence is that CPV is derived from FPLV in cats or from FPLV-like viruses in wild animals by natural genetic mutation. Genetic analyses of parvovirus DNA obtained from a number of wild carnivore isolates might support the latter hypothesis (26,30,31).Since the emergence of CPV-2, new antigenic types of this virus (which can be distinguished using specific monoclonal antibodies) have arisen (18,19). These antigenic variants have been designated CPV type 2a (CPV-2a) and type 2b (CPV-2b). CPV-2a was first isolated in 1979, while CPV-2b was not isolated until 1984 (19). CPV-2a and -2b replaced the original CPV-2 worldwide in a relatively short period in dogs.CPV strains can replicate in both canine and feline cells in culture, whereas FPLV strains can replicate efficiently only in feline cells (9,13,27). Recently, Truyen et al. (28,29) reported that approximately 5% of FPV isolates from domestic cats from Germany and the United States were either CPV-2a or -2b and, furthermore, CPV-2a and -2b could replicate in feline tissues, while the original CPV-2 could not. CPV-2a and -2b infections in large felids were recently observed by Steinel et al. (24). These observations indicate that the host range of CPV-2a and -2b has now expanded into domestic cats and the wild felids. In addition, we have demonstrated that CPV-2a and -2b are prevalent in cat populations in southeast Asia (7). We isolated several CPV strains from peripheral blood mononuclear cells (PBMCs) of apparently healthy Vietnamese leopard cats (Felis bengalensis) which had high titers of virus-neutralizing (VN) antibodies (8). Intriguingly, among the strains of CPV designated LCPV, three viral strains (V139, V140, and V203) were regarded as new antigenic types which were less reactive to conventional anti-CPV monoclonal antibodies than FPLV, CPV-2, and CPV-2a and -2b (7). Sequence analyses of the VP2 genes of these viruses revealed that they were closely related to either CPV-2a or -2b but commonly possessed a specific amino acid substitution at residue 300 in the VP2 capsid protein. Therefore, we named these new antigenic type strains CPV type 2c (CPV-2c) (7).The pathogenicities of CPV-2a and -2b in cats are not fully understood. Mochizuki et al. (14) isolated a strai...
Organic/inorganic hybrid thin films for protein recognition have been prepared by the liquid-phase deposition (LPD) coupled with template synthesis, i.e., molecular imprinting, where pepsin (Pep) was used as a model protein and titanium oxide was deposited on gold substrates in the presence of Pep-poly-L-lysine (PL) complexes. The complexes remained in the templated film after the deposition, and the binding sites for Pep were constructured after Pep was removed from the film. Surface plasmon resonance signals on the deposited films were measured to examine the binding behaviors toward proteins. The binding of Pep on the templated film was reversible, and the binding isotherm of Pep depicted a saturation curve with a binding constant of 7.3 x 105 M(-1), which was 10 times higher than that of albumin. In contrast, titanium oxide films prepared without PL did not show any selectivity; therefore, the hybridization of PL as the organic binder with the inorganic material is necessary to obtain selective binding sites for Pep. It was also shown that the hybridization process should proceed without denaturing the template protein, in order to obtain selective binding sites for the template. The procedure for preparation of the films was simple to perform, and the process for hybridization of the thin films with nanometer-order thickness was easily controlled by changing the LPD reaction time period. Consequently, the proposed LPD coupled with template synthesis is among the most appropriate methods to prepare hybrid materials with protein recognition ability, which proceeds under mild conditions in aqueous solution.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.