The evolution of two homologues of the core protein VP6 of epizootic haemorrhagic disease virus (EHDV), which correspond to the geographical origin of the virus

Epizootic haemorrhagic disease virus is a 10-segmented, double-stranded RNA virus. When these ten segments of dsRNA are run on 1% agarose, eastern (Australia, Japan) and western (North America, Africa, Middle-East) strains of the virus can be separated phenotypically based on the migration of genome segments 7-9. In western strains, segments 7-9 are roughly the same size and co-migrate as a single RNA band. In eastern strains, segment 9 is smaller, so while segments 7 and 8 co-migrate, the segment 9 RNA runs faster than its western homologue. Translation experiments demonstrated that these two segment 9 homologues are both functional and produce proteins (VP6) of different sizes-something that has not been reported in any other orbivirus species to date. Sequence analysis suggests that eastern and western versions of segment 9 (VP6) have likely evolved as a response to adaptive selection in different geographical regions via gene duplication and subsequent mutation. These significant findings are considered unusual given the conserved nature of VP6 and its presumed role as the viral helicase. It is not currently known what the biological relevance of each homologue is to the virus

Biomarkers of Epileptogenesis: Psychiatric Comorbidities (?)

The last decade has witnessed a significant shift on our understanding of the relationship between psychiatric disorders and epilepsy. While traditionally psychiatric disorders were considered as a complication of the underlying seizure disorder, new epidemiologic data, supported by clinical and experimental research, have suggested the existence of a bidirectional relation between the two types of conditions: not only are patients with epilepsy at greater risk of experiencing a psychiatric disorder, but patients with primary psychiatric disorders are at greater risk of developing epilepsy. Do these data suggest that some of the pathogenic mechanisms operant in psychiatric comorbidities play a role in epileptogenesis? The aim of this article is to review the epidemiologic data that demonstrate that primary psychiatric disorders are more frequent in people who develop epilepsy, before the onset of the seizure disorder than among controls. The next question looks at the available data of pathogenic mechanisms of primary mood disorders and their potential for facilitating the development and/or exacerbation in the severity of epileptic seizures. Finally, we review data derived from experimental studies in animal models of depression and epilepsy that support a potential role of pathogenic mechanisms of mood disorders in the development of epileptic seizures and epileptogenesis. The data presented in this article do not yet establish conclusive evidence of a pathogenic role of psychiatric comorbidities in epileptogenesis, but raise important research questions that need to be investigated in experimental, clinical, and population-based epidemiologic research studies. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s13311-014-0271-4) contains supplementary material, which is available to authorized users