Spatial variation in the parasite communities and genomic structure of urban rats in New York City.

Brown rats (Rattus norvegicus) are a globally distributed pest. Urban habitats can support large infestations of rats, posing a potential risk to public health from the parasites and pathogens they carry. Despite the potential influence of rodent-borne zoonotic diseases on human health, it is unclear how urban habitats affect the structure and transmission dynamics of ectoparasite and microbial communities (all referred to as "parasites" hereafter) among rat colonies. In this study, we use ecological data on parasites and genomic sequencing of their rat hosts to examine associations between spatial proximity, genetic relatedness and the parasite communities associated with 133 rats at five sites in sections of New York City with persistent rat infestations. We build on previous work showing that rats in New York carry a wide variety of parasites and report that these communities differ significantly among sites, even across small geographical distances. Ectoparasite community similarity was positively associated with geographical proximity; however, there was no general association between distance and microbial communities of rats. Sites with greater overall parasite diversity also had rats with greater infection levels and parasite species richness. Parasite community similarity among sites was not linked to genetic relatedness of rats, suggesting that these communities are not associated with genetic similarity among host individuals or host dispersal among sites. Discriminant analysis identified site-specific associations of several parasite species, suggesting that the presence of some species within parasite communities may allow researchers to determine the sites of origin for newly sampled rats. The results of our study help clarify the roles that colony structure and geographical proximity play in determining the ecology of R. norvegicus as a significant urban reservoir of zoonotic diseases. Our study also highlights the spatial variation present in urban rat parasite communities, indicating that rats across New York City are not reservoirs for a homogenous set of parasites and pathogens. As a result, the epidemiological risks may be similarly heterogeneous for people in urban habitats.

Clinical evaluation of new automated cytomegalovirus IgM and IgG assays for the Elecsys(®) analyser platform.

Cytomegalovirus (CMV) is a leading cause of physical and neurological abnormalities in newborns. Hence, the diagnosis of CMV infection in pregnant women is necessary in order to allow appropriate management of their pregnancy. New assays have been developed for the Roche Elecsys® immunoassay platform that detect CMV-specific immunoglobulin (Ig)M and IgG, with the IgM assay designed to target IgM produced at the start of infection rather than IgM persisting later in infection. This study aimed to evaluate the performance of the new assays compared with other commercial kits widely distributed in laboratories. The performance of the Elecsys and comparator CMV IgM and IgG assays was assessed using 967 preselected patient samples characterised by CMV infection status, as well as being compared using 1,668 unselected clinical samples. The Elecsys CMV IgM and IgG assays performed consistently with comparator assays using the preselected samples. The Elecsys CMV IgM assay showed improved sensitivity compared with the Enzygnost® assay in primary infection (91.2 % vs. 79.4 %) and improved specificity over the Architect® assay in potentially cross-reacting samples (94.1 % vs. 82.4 %). The Elecsys IgM assay reported fewer positive results in the later stages of CMV infection compared with ETI-CYTOK-M ELISA, while the Elecsys IgG assay reported slightly fewer negative results in the early stages of infection compared with ETI-CYTOK-G ELISA. There was good agreement between Elecsys and comparator assays using unselected clinical samples (range 90.4-99.4 %). The Elecsys CMV IgM and IgG assays compare well with routinely used assays and are suitable for clinical use.

Identification of the protein product of the c-mos proto-oncogene in mouse testes.

The mouse c-mos proto-oncogene RNA is expressed primarily in mouse gonadal tissues and embryos. Until now, the c-mos protein has not been identified. Utilizing two different site-directed affinity purified anti-peptide antibodies, we have identified a 43 kDa c-mos protein in mouse testes and in germ cell preparations derived from testes. This 43 kDa testicular protein was found to be structurally related to a bacterially expressed c-mos protein by peptide mapping. Immunoblots of whole mouse sections were employed to establish that the c-mos protein is expressed primarily in the testes.