Biomedical subjects

Varpu Hirvelä-Koski

Publications and source records attributed to Varpu Hirvelä-Koski.

3 recordsLinked to original sources

PubMed2004

Renibacterium salmoninarum: effect of hypochlorite treatment, and survival in water.

The effect of different concentrations of sodium hypochlorite on Renibacterium salmoninarum and the survival of the bacterium in autoclaved river water and groundwater were examined. The disinfection trial was performed using R. salmoninarum ATCC 33209. The concentrations of free chlorine were 10, 50, 100 and 200 mg 1(-1), the contact times were 5, 15, and 30 min and 24 h, and the test suspensions were subcultured both on Kidney disease medium (KDM2) agar and in 3 parallel KDM2 broths, which were then subcultured on KDM2 and selective KDM (SKDM) agar. The survival of the bacterium in river water and groundwater was studied using 4 isolates of R. salmoninarum including ATCC 33209. Treatment with sodium hypochlorite effectively reduced the number of culturable cells of R. salmoninarum, but use of the recovery broth showed that small numbers of cells remained viable at all concentrations of free chlorine. The numbers of R. salmoninarum decreased to an undetectable level after 4 wk incubation in the survival trials, but low numbers of colonies were again found in the subculture after 5 wk incubation. Viable cells of R. salmoninarum were still detected in subcultures of all strains after 20 wk of incubation in river water.

Agar↗

PubMed2004

Recent isolates of parapoxvirus of Finnish reindeer (Rangifer tarandus tarandus) are closely related to bovine pseudocowpox virus.

Cases of papular stomatitis in Finnish reindeer have been reported for many years. The causative agent was thought to be Orf virus (ORFV), one of the Parapoxviridae, although this assumption was based mainly on clinical symptoms, pathology and electron microscopy. Here sequence analyses of the viral DNA isolated from a recent outbreak of disease in 1999-2000 are presented in comparison to that isolated from earlier outbreaks in 1992-1994. The results show that the virus isolated from the 1999-2000 outbreak is most closely related to Pseudocowpox virus, whereas those from previous years grouped with ORFV. The present study describes a method for genetic characterization and classification of parapoxviruses (PPVs) and provides for the first time an extended phylogenetic analysis of PPVs isolated from Finland, established members of the genus Parapoxvirus and selected members of the subfamily Chordopoxvirinae.

Amino Acid Sequence↗

PubMed2003

Echinococcus granulosus in Finland.

Echinococcus granulosus is shown to occur in eastern Finland in a sylvatic cycle involving wolves (Canis lupus) as the definitive host and reindeer (Rangifer tarandus tarandus) and probably also elk (Alces alces) and the wild forest reindeer (Rangifer tarandus fennicus) as intermediate hosts. Even though the prevalence of E. granulosus in reindeer has increased in recent years, it is still very low (<0.013%). The results suggest, however, that the reindeer is a good sentinel animal to show the contamination of soil with Echinococcus eggs. This is the first report of wolves acting as a definitive host for E. granulosus in northern Europe. The parasite seems to be quite common in the Finnish wolf population, with a prevalence of approximately 30% in both intestinal and faecal samples. The present results and previous ones indicate that E. granulosus infection has not spread to dogs in the reindeer herding area.

Animals↗