Faculty Bibliography

The mechanisms responsible for determining neural stem cell fate are numerous and complex. To begin to identify the specific components involved in these processes, we generated several mouse neural stem cell (NSC) antibodies against cultured mouse embryonic neurospheres. Our immunohistochemical data showed that the NSC-6 antibody recognized NSCs in the developing and postnatal murine brains as well as in human brain organoids. Mass spectrometry revealed the identity of the NSC-6 epitope as brain abundant, membrane-attached signal protein 1 (BASP1), a signaling protein that plays a key role in neurite outgrowth and plasticity. Western blot analysis using the NSC-6 antibody demonstrated multiple BASP1 isoforms with varying degrees of expression and correlating with distinct developmental stages. Herein, we describe the expression of BASP1 in NSCs in the developing and postnatal mammalian brains and human brain organoids, and demonstrate that the NSC-6 antibody may be a useful marker of these cells.

Epilepsy is a common neurological disorder affecting over 70 million people worldwide, with a high rate of pharmaco-resistance, diverse comorbidities including progressive cognitive and behavioural disorders, and increased mortality from direct (e.g. sudden unexpected death in epilepsy, accidents, drowning) or indirect effects of seizures and therapies. Extensive research with animal models and human studies provides limited insights into the mechanisms underlying seizures and epileptogenesis, and these have not translated into significant reductions in pharmaco-resistance, morbidities or mortality. To help define changes in molecular signalling networks associated with seizures in epilepsy with a broad range of aetiologies, we examined the proteome of brain samples from epilepsy and control cases. Label-free quantitative mass spectrometry was performed on the hippocampal cornu ammonis 1-3 region (CA1-3), frontal cortex and dentate gyrus microdissected from epilepsy and control cases (n = 14/group). Epilepsy cases had significant differences in the expression of 777 proteins in the hippocampal CA1 - 3 region, 296 proteins in the frontal cortex and 49 proteins in the dentate gyrus in comparison to control cases. Network analysis showed that proteins involved in protein synthesis, mitochondrial function, G-protein signalling and synaptic plasticity were particularly altered in epilepsy. While protein differences were most pronounced in the hippocampus, similar changes were observed in other brain regions indicating broad proteomic abnormalities in epilepsy. Among the most significantly altered proteins, G-protein subunit beta 1 (GNB1) was one of the most significantly decreased proteins in epilepsy in all regions studied, highlighting the importance of G-protein subunit signalling and G-protein-coupled receptors in epilepsy. Our results provide insights into common molecular mechanisms underlying epilepsy across various aetiologies, which may allow for novel targeted therapeutic strategies.

OBJECTIVE:To examine social, economic, and migratory influences on the health of racial and ethnic minority groups in Canada, with a special focus on Caribbean immigrants. METHODS:Combined annual cycles (2011-2016) of the Canadian Community Health Survey (CCHS) data totaling over 300,000 adult Canadian residents were aggregated. Descriptive statistics and multivariable logistic regression models were used to examine the prevalence and associated factors of (1) cardiovascular disease diagnosed by a healthcare professional, and (2) self-rated general health among racial and ethnic groups. RESULTS:Caribbeans in general, Black and other non-White Canadians had significantly higher odds (adjusted for age/sex) of reporting any cardiovascular disease compared with White Canadians. Only non-Caribbean Blacks had higher odds of self-rated fair or poor general health compared with White Canadians. Multivariate logistic regression models revealed that after controlling for social and demographic factors, immigration status and years since migration, Caribbean non-Blacks and Black Caribbeans were at higher odds of having a doctor-reported cardiovascular health condition compared with White Canadians. Caribbean non-Blacks also had higher odds of fair or poor self-rated health than White Canadians. CONCLUSION:The results of this study highlight the need for additional investigations of other potential influences on physical health statuses, especially among migrants and those of African ancestry who might be more prone to adverse health outcomes.

The management of women with epilepsy (WWE) presents many challenges for physicians. The primary goal during pregnancy is to achieve the best possible control of seizures with the least adverse effects associated with exposure to antiseizure medications (ASMs). Even though the guidelines for managing pregnant WWE are expanding, no definitive guidelines exist for the treatment of status epilepticus (SE). Additionally, much of our data comes from the effect of generalized tonic clonic seizures on the fetus. There is very little data on the effect of focal seizures and even less on focal SE. Here we present two cases of pregnant WWE who presented in focal SE, who underwent simultaneous video-EEG monitoring and fetal heart tracing (FHT). During each focal seizure the FHT demonstrated a normal baseline heart rate with moderate variability. In the second case due to continuous seizures more aggressive treatment had to be started. This led to maternal relative autonomic instability as well as absent variability on FHT. These findings raise many questions on the management of focal SE during pregnancy including if the effect of treatment is worse than the seizures, and how do we balance our goals for both mother and fetus?