Molecular and life-history effects of a natural toxin on herbivorous and non-target soil arthropods

Natural toxins, such as isothiocyanate (ITC), are harmful secondary metabolites produced by plants. Many natural toxins occur in commercial crops, yet their possible negative repercussions on especially non-target soil organisms are largely unknown. This study examined life-history and gene transcriptional responses to 2-phenylethyl ITC on two soil arthropod species: Folsomia candida and Protaphorura fimata. To that end the standardized ISO guideline for ecotoxicological tests and a microarray for F. candida were used. The dissipation of 2-phenylethyl ITC in natural soil was investigated using GC-MS/MS for quantification. Half-lives, tested at four concentration levels in natural soil, were on average 16 h with biodegradation as the plausible main removal process. Regardless, toxic effects on reproduction were shown for F. candida and P. fimata, with EC50 values of around 11.5 nmol/g soil illustrating the toxic character of this compound. Gene expression profiles revealed the importance of fatty acid metabolism at low exposure concentrations (EC10), which is associated with the lipophilic nature of 2-phenylethyl ITC. At higher concentrations (EC50) gene expression became more ubiquitous with over-expression of especially stress-related genes and sugar metabolism. The regulation of a gene encoding a precursor of follistatin, furthermore, implied the inhibition of reproduction and may be an important molecular target that can be linked to the observed adverse effect of life-history traits

Feasibility and usefulness of the peer-run course ‘‘Recovery Is Up to You’’ for people with addiction problems: A qualitative study

“Recovery Is Up to You,” a 12-week peer-run group experience for persons with major psychiatric problems, has had positive effects on important elements of recovery: empowerment, hope, and self-efficacy beliefs. Determining if such an experience would be equally efficacious for persons with addiction problems is the focus of this study. The 12-week course was experienced by eight groups of persons with addiction problems and the outcome, measured in terms of the response of participants and of the group leaders, was a favorable one as the course was found to be supportive of the recovery process, providing the participants and peer group leaders alike with new perspectives on meaningful living. Keywords: Peer-run course, recovery, addiction, addiction car