Faculty Bibliography

PURPOSE/OBJECTIVE:Neurologic determination of death (NDD) is legally accepted as death in Canada but remains susceptible to misunderstandings. In some cases, families request continued organ support after NDD. Conflicts can escalate to formal legal challenges, causing emotional, financial, and moral distress for all involved. We describe prevalence, characteristics, and common experiences with requests for continued organ support following NDD in Canada. METHODS:Mixed-methods design combining anonymous online survey with semi-structured interviews of Canadian critical care physicians (448 practitioners, adult and pediatric). RESULTS:One hundred and six physicians responded to the survey and 12 participated in an interview. Fifty-two percent (55/106) of respondents had encountered a request for continued organ support after NDD within two years, 47% (26/55) of which involved threat of legal action. Requests for continued support following NDD ranged from appeals for time for family to gather before ventilator removal to disagreement with the concept of NDD. Common responses to requests included: consultation with an additional physician (54%), consultation with spiritual services (41%), and delay of one to three days for NDD acceptance (49%). Respondents with prior experience were less likely to recommend ancillary tests (P = 0.004) or consultation with bioethics services (P = 0.004). Qualitative analysis revealed perceptions that requests for continued organ support were driven by mistrust, tensions surrounding decision-making, and cultural differences rather than a lack of specific information about NDD. CONCLUSIONS:Family requests for continued somatic support following NDD were encountered by half our sample of Canadian critical care physicians. Mitigation strategies require attention to the multifaceted social contexts surrounding these complex scenarios.

Current treatments for autism spectrum disorders (ASD) are limited in efficacy and are often associated with substantial side effects. These medications typically ameliorate problem behaviors associated with ASD, but do not target core symptom domains. As a result, there is a significant amount of research underway for development of novel experimental therapeutics. Endocannabinoids are arachidonic acid-derived lipid neuromodulators, which, in combination with their receptors and associated metabolic enzymes, constitute the endocannabinoid (EC) system. Cannabinoid signaling may be involved in the social impairment and repetitive behaviors observed in those with ASD. In this review, we discuss a possible role of the EC system in excitatory-inhibitory (E-I) imbalance and immune dysregulation in ASD. Novel treatments for the core symptom domains of ASD are needed and phytocannabinoids could be useful experimental therapeutics for core symptoms and associated domains.

High-throughput experiments suggest that almost 20% of human proteins may be S-palmitoylatable, a post-translational modification (PTM) whereby fatty acyl chains, most commonly palmitoyl chain, are linked to cysteine thiol groups that impact on protein trafficking, distribution and function. In human, protein S-palmitoylation is mediated by a group of 23 palmitoylating 'Asp-His-His-Cys' domain-containing (DHHC) enzymes. There is no information on the scope of protein S-palmitoylation, or the pattern of DHHC enzyme expression, in the heart. We used resin-assisted capture to pull down S-palmitoylated proteins from human, dog, and rat hearts, followed by proteomic search to identify proteins in the pulldowns. We identified 454 proteins present in at least 2 species-specific pulldowns. These proteins are operationally called 'cardiac palmitoylome'. Enrichment analysis based on Gene Ontology terms 'cellular component' indicated that cardiac palmitoylome is involved in cell-cell and cell-substrate junctions, plasma membrane microdomain organization, vesicular trafficking, and mitochondrial enzyme organization. Importantly, cardiac palmitoylome is uniquely enriched in proteins participating in the organization and function of t-tubules, costameres and intercalated discs, three microdomains critical for excitation-contraction coupling and intercellular communication of cardiomyocytes. We validated antibodies targeting DHHC enzymes, and detected eleven of them expressed in hearts across species. In conclusion, we provide resources useful for investigators interested in studying protein S-palmitoylation and its regulation by DHHC enzymes in the heart. We also discuss challenges in these efforts, and suggest methods and tools that should be developed to overcome these challenges.

OBJECTIVE:We aimed to describe how often and why clinicians counsel people with epilepsy about sudden unexpected death in epilepsy (SUDEP). Understanding counseling gaps can help design interventions. METHODS:We searched clinical notes of 77,924 patients from 2010 to 2014 from six hospitals to find examples of SUDEP counseling and seizure safety counseling. Visits were coded for patient, clinician, and visit factors, and documented reasons for counseling. We evaluated factors associated with SUDEP vs. seizure safety counseling, and reasons for counseling using bivariate and multivariable statistics. Reasons for counseling included: poor medication adherence, lifestyle factors (e.g., poor sleep, drinking alcohol), patient/family reluctance to make recommended medication adjustment, epilepsy surgery considerations, and patient education only. RESULTS:(4, n = 996) = 3.81, p = 0.43. Adult neurologists were more likely to document SUDEP counseling than pediatric (OR = 1.65, 95% CI = 1.12-2.44). Most SUDEP counseling was documented with a goal of seizure reduction (214 of 332, 64.5%), though some was for patient education only (118 of 332, 35.5%). By the time SUDEP counseling was documented, the majority of patients had refractory epilepsy (187 of 332, 56.3%) and/or a potentially modifiable risk factor (214 of 332, 64.5%). Neurologists with more years of clinical experience (OR = 2.18, 95% CI = 1.12-4.25) and more senior academic titles (OR = 2.25, 95% CI = 1.27-3.99) were more likely to document SUDEP counseling for patient education only. People with ≥2 anti-seizure medications (ASM) were more likely to receive counseling for patient education (OR = 2.72, 95% CI = 1.49-4.97). CONCLUSIONS:Documentation of SUDEP is rare, and varies by clinician, hospital, and patient factors. Efforts to increase SUDEP counseling should focus on junior clinicians, and emphasize starting the conversation soon after onset of epilepsy.

BACKGROUND:Cognitive impairment due to multiple sclerosis (MS) is common and often limits occupational functioning, contributes to disability, and reduces quality of life. Early detection of cognitive involvement in MS is critical for treatment planning and intervention, and frequent, regular cognitive monitoring may provide insight into subtle changes in disease progression. OBJECTIVE:To compare the sensitivity and specificity of clinical, computer-based and experimental measures to early cognitive involvement in MS. METHODS:Cognitive functioning was compared in MS participants early in the disease course to matched healthy controls using conventional, computer-based and functional assessments: the Brief International Cognitive Assessment in MS (BICAMS); the computer-based Cogstate Brief Battery (CBB); the Attention Network Test-Interaction (ANT-I), including intra-individual variability; and the Test of Everyday Cognitive Ability (TECA), a functional measure of instrumental activities of daily living. RESULTS:MS participants (n = 25, mean disease duration= 5.82 ± 3.65 years) and demographically matched healthy controls (n = 29) completed the cognitive assessments. The Cogstate measure of choice reaction time (AUC = 0.73, p = .004), intra-individual variability on the ANT-I (AUC = 0.79, p = .001), and TECA (AUC = 0.78, p = .001) scores were the most sensitive and specific markers of cognitive involvement in MS. CONCLUSIONS:Brief, repeatable, computer-based measures of reaction time and variability detect early MS associated cognitive involvement.