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Myelinated axons have a distinct protein architecture essential for action potential propagation, neuronal communication, and maintaining cognitive function. Damage to myelinated axons, associated with cerebral hypoperfusion, contributes to age-related cognitive decline. We sought to determine early alterations in the protein architecture of myelinated axons and potential mechanisms after hypoperfusion. Using a mouse model of hypoperfusion, we assessed changes in proteins critical to the maintenance of paranodes, nodes of Ranvier, axon- glial integrity, axons, and myelin by confocal laser scanning microscopy. As early as 3 d after hypoperfusion, the paranodal septate-like junctions were damaged. This was marked by a progressive reduction of paranodal Neurofascin signal and a loss of septate-like junctions. Concurrent with paranodal disruption, there was a significant increase in nodal length, identified by Nav1.6 staining, with hypoperfusion. Disruption of axon- glial integrity was also determined after hypoperfusion by changes in the spatial distribution of myelin-associated glycoprotein staining. These nodal/paranodal changes were more pronounced after 1 month of hypoperfusion. In contrast, the nodal anchoring proteins AnkyrinG and Neurofascin 186 were unchanged and there were no overt changes in axonal and myelin integrity with hypoperfusion. A microarray analysis of white matter samples indicated that there were significant alterations in 129 genes. Subsequent analysis indicated alterations in biological pathways, including inflammatory responses, cytokinecytokine receptor interactions, blood vessel development, and cell proliferation processes. Our results demonstrate that hypoperfusion leads to a rapid disruption of key proteins critical to the stability of the axon- glial connection that is mediated by a diversity of molecular events. [ABSTRACT FROM AUTHOR]

The aim of this experiment was to investigate whether vestibular compensation following unilateral vestibular deafferentation (UVD) is associated with changes in the expression of GABAA receptor subunits in the guinea pig vestibular nuclear complex (VNC) at 2, 10, and 30 h post-surgery. Using Western blotting, the α1 and γ2 subunits (but not the β2 subunit) were detected in the VNC of labyrinthine-intact animals. However, there were no significant differences in the protein expression of the α1 and γ2 subunits within the ipsilateral or contralateral VNC at any time post-UVD compared to sham and anesthetic controls. Furthermore, UVD did not induce the expression of the β2 protein. These results suggest that vestibular compensation in guinea pig, as in the rat, is not associated with changes in the protein levels of the GABAA receptor subunits α1, β2, and γ2 in the VNC. However, a limitation of this study is that the Western blotting technique can detect only changes that are larger than 30% and therefore small changes cannot be excluded. [ABSTRACT FROM AUTHOR]

Our aim was to develop a teaching paradigm that connected undergraduate's neuropharmacological/toxicological knowledge to that of government policy. One goal of undergraduate education should be to help develop scientists that can use their scientific knowledge to critique government policy. There is little research, however, on whether democratization of science occurs: nor how to achieve this. Our work focused on a semi-structured workshop designed around the Psychoactive Substances Bill (PSB). Third year science students were given a questionnaire that was designed to address whether participating in the workshop enhanced their understanding of the PSB and its relationship to their established knowledge (i.e., transfer learning). Furthermore, whether they felt that they had enough expertise to consider making a submission (i.e., societal engagement). Results showed that the students appreciated the opportunity to explore potential application of their knowledge and delve into a socio-scientific issue. However, our findings suggested they felt uncomfortable discussing their ideas outside the classroom: nor, did they identify themselves as having sufficient knowledge to contribute to a submission. In conclusion, this study highlights two points. First, that discussion based transfer learning can be used in the tertiary sector and students value the opportunity to apply their knowledge to socio-scientific issue. Second, if social participation and democratization of science is a goal, then more emphasis should be placed on how students can realistically and confidently apply their learning to change social policy. In order to achieve this, education programs need to focus on legitimate real-life processes such as the PSB for engagement.