Trans-sulcal parafascicular approach to subcortical lesions

Historically, neoplasms which are located in the subcortical region of the brain are considered technically difficult to access. As such, tumours in these locations are usually avoided, due to the risks associated with traversing eloquent cortex, the disrupting of white matter tracts, or the need to use narrow corridors to approach the lesion. Tubular retractors are able to gently displace brain parenchyma and white matter in an atraumatic fashion to access these deep regions. We demonstrate a minimally invasive trans-sulcal parafascicular approach using the Brainpath system (NICO Corp, Indianapolis, Indiana) to a caudate head metastasis as a representative case.

Natural Loss of eyeless/Pax6 Expression in Eyes of Bicyclus anynana Adult Butterflies Likely Leads to Exponential Decrease of Eye Fluorescence in Transgenics

Commonly used visible markers for transgenesis use fluorescent proteins expressed at the surface of the body, such as in eyes. One commonly used marker is the 3xP3-EGFP cassette containing synthetic binding sites for the eyeless/Pax6 conserved transcription factor. This marker cassette leads to fluorescent eyes in a variety of animals tested so far. Here we show that upon reaching adulthood, transgenic Bicyclus anynana butterflies containing this marker cassette exponentially loose fluorescence in their eyes. After 12 days, transgenic individuals are no longer distinguishable from wild type individuals. The decreased eye fluorescence is likely due to significantly decreased or halted eyeless/Pax6 expression observed in wild type animals upon adult emergence. Implications from these findings include care in screening transgenic animals before these reach adulthood, or shortly thereafter, and in using adult animals of the same age for quantitative screening of likely homozygote and heterozygote individuals.