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A novel integrated transgenic Caenorhabditis elegans strain (PC161) incorporates a double reporter construct with green fluorescent protein (GFP) and lacZ genes fused in-frame into the second exon of the hsp16-1 gene. This construct also includes the Simian Virus 40 (SV40) nuclear localization signal such that the fusion protein accumulates in the nuclei of expressing cells. The PC161 strain was used to monitor the effects of several known stressors, including heat, cadmium, and microwave radiation. The time course of induction was similar for both reporters but was strongly influenced by pretreatment conditions. The PC161 worms kept at 15 degrees C beforehand showed a steady increase in reporter expression (up to at least 16 h) when heated to 30 degrees C. However, if washed on ice prior to heat stress at 30 degrees C, PC161 worms showed a much steeper rise in reporter expression, reaching a maximum after 2.5 h and then plateauing. Heat shock induced strong expression of both reporter genes in all tissues apart from the germ line and early embryos. A highly significant linear dose-response relationship was observed for both transgenes with increasing cadmium concentrations (5-100 microg/ml). Prolonged exposure to microwave radiation (750 MHz and 0.5 W for 16 h) also induced expression of both transgenes at 25 and (to some extent) 27 degrees C, but only beta-galactosidase activity was detectable at 23 degrees C, and neither reporter was detectably expressed at 21 degrees C. Throughout all exposures, the lacZ reporter product was more readily detectable than coexpressed GFP. However, the GFP reporter affords opportunities to monitor the stress response in living worms.

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A herpesvirus causing a cytopathic effect was isolated from pulmonary fibroblast cultures established from a European badger (Meles meles).A study was undertaken to classify and to assess some in-vitro growth characteristics of this virus. From a panel of 27 mammalian cell lines, in-vitro replication of the badger herpesvirus (BadHV) was only demonstrated with a mink lung cell line, suggesting a high degree of host specificity. Using PCR with degenerate primers, three independent fragments of the BadHV genome were sequenced. The largest of these fragments comprised a 6n2 kb segment including the DNA polymerase and glycoprotein B genes. Phylogenetic analysis of these sequences demonstrated that the BadHV is novel and clearly grouped with members of the Gammaherpesvirinae. In view of the oncogenic and immunosuppressive potential of many related herpesviruses, it is possible that BadHV can impact on existing acute or chronic disease in badgers.This report describes the partial characterization of a herpesvirus isolated from a European badger (Meles meles). The cytopathic effect (CPE) caused by this virus appeared in primary pulmonary fibroblast cultures established during the course of studies to evaluate a candidate DNA vaccine for Mycobacterium bovis (Chambers et al., 2001). These cultures were established from tissues collected as part of a statutory removal operation from a young adult female badger from Cornwall, South-West England, in 1996. At the time of presentation, this badger was in a poor nutritional state, weighing 6n0 kg. Post-mortem examination revealed a few scattered, 1 mm-diameter, white foci in the liver parenchyma and in the cortex of each kidney. Poorly defined 0n5 mm lesions were also observed in each lobe of the lungs. Histological examination of the lungs revealed multiple eosinophilic granulomas and diffuse inflammatory changes with eosinophils as the prominent cell type ; the changes were of the type observed in verminous pneumonia. In the kidneys and liver, there were multifocal inflammatory mononuclear cell infiltrates in the interstitium. However, no inclusion bodies or other histological changes characteristic of virus infection were observed. Cultural, histopathological and immunological tests for the diagnosis of M. bovis infection proved negative.After harvesting alveolar macrophages from lungs, a portion of the apical lobe was removed and comminuted and cells were dispersed using trypsin prior to seeding onto plastic culture flasks as described by Chambers et al. (2001). Once confluent, cultures were passaged by splitting at a ratio of 1 : 2. These cells were examined microscopically on alternate days. On the fourth passage, a CPE resembling that of a herpesvirus was observed. Examination of the infected cells by electron microscopy confirmed the presence of enveloped, herpesviruslike particles with a capsid diameter of approximately 105 nm. Since there are no published reports of a herpesvirus in this species, a more detailed investigation into the phenotypic characteristics and m...