Faculty Bibliography

OBJECTIVE:To evaluate the exploratory time to exceed pre-randomization seizure count (T-PSC) in the determination of efficacy of adjunctive perampanel in participants with primary generalized tonic-clonic (PGTC) seizures in generalized-onset epilepsy. METHODS:In this multicenter, double-blind study (ClinicalTrials.gov identifier: NCT01393743), participants ≥12 years of age with treatment-resistant idiopathic generalized epilepsy were randomized to receive placebo or adjunctive perampanel (≤8 mg/day) across a 17-week double-blind treatment phase (4-week titration; 13-week maintenance). We evaluated the pre-planned exploratory end point of the T-PSC using a Kaplan-Meier analysis. We also re-evaluated the correspondence of the primary end points of median percent seizure frequency change (MPC) and 50% responder rate (50RR) calculated at T-PSC and at the end of the trial. RESULTS:The exploratory end point of median T-PSC on placebo was 43 days and >120 days on perampanel (log-rank p < .001). The primary end points calculated at T-PSC did not differ significantly from the end points at the end of the trial (MPC -31% vs -42% at T-PSC; 50RR 32% vs 51% at T-PSC). After T-PSC was reached, participants had a median (interquartile range) of 5 (3-13) additional seizures on placebo and 5 (2-10) on perampanel. SIGNIFICANCE/CONCLUSIONS:The exploratory end point of T-PSC demonstrated the effectiveness of perampanel despite a shorter duration of monitoring. The seizures that occurred after T-PSC did not influence the conclusions of the trial; therefore, T-PSC may be a viable alternative to traditional trial end points that reduces the risk to participants.

A large portion of stroke disparities remains unexplained, even after adjusting for demographic, comorbidity, and health care access variables. There is a critical need to close this knowledge gap by investigating novel factors that may contribute to stroke disparities. Allostatic load (AL) is the lifetime adverse physiologic impact of needing to adjust to socially structured stressors such as racism. AL has been shown to increase health vulnerability and worsen outcomes in marginalized populations. We sought to assess the differential impact of AL on cognitive outcomes post intracerebral hemorrhage (ICH) across race-ethnicity. The Intracerebral Hemorrhage Outcomes Project (ICHOP) prospectively collected data from patients presenting to Columbia Medical Center with ICH from 3/2009 to 5/2016. Data included demographics, stroke scores, labs, complications, neuroimaging, medical history, and discharge data. Five markers of AL (HbA1c, WBC, SBP, HR, ALB) were obtained. An AL score was generated by summing the elements in each patient that fell outside normal ranges, with AL score ranging 0-5. A linear regression model, adjusted for stroke severity and ICH volumes, was used to evaluate the relationship between AL and Modified Telephone Interview for Cognitive Status (TICS-m) at discharge, stratified by race-ethnicity. Among 248 white, 195 black, and 261 Hispanic ICH patients, neither mean AL nor mean TICS differed by race/ethnicity (p = 0.51, p = 0.79 respectively). In the overall cohort AL did not predict TICS at discharge (Beta -1.0, SE 1.1, p = 0.353). In Whites (beta 1.18, SE 2.5, p = 0.646) and Hispanics (beta -0.95, SE 1.6, p = 0.552) AL was not associated with TICS at discharge. In Black patients, higher AL was associated with a decrease in TICS at discharge (beta -3.2, SE 1.5, p = 0.049). AL is an important determinant of post ICH outcomes for certain minority populations. AL may explain some of the unexplained health disparities in stroke populations.

Decades of rodent research have established the role of hippocampal sharp wave ripples (SPW-Rs) in consolidating and guiding experience. More recently, intracranial recordings in humans have suggested their role in episodic and semantic memory. Yet, common standards for recording, detection, and reporting do not exist. Here, we outline the methodological challenges involved in detecting ripple events and offer practical recommendations to improve separation from other high-frequency oscillations. We argue that shared experimental, detection, and reporting standards will provide a solid foundation for future translational discovery.

Early diagnosis of Alzheimer's disease plays a pivotal role in patient care and clinical trials. In this study, we have developed a new approach based on 3D deep convolutional neural networks to accurately differentiate mild Alzheimer's disease dementia from mild cognitive impairment and cognitively normal individuals using structural MRIs. For comparison, we have built a reference model based on the volumes and thickness of previously reported brain regions that are known to be implicated in disease progression. We validate both models on an internal held-out cohort from The Alzheimer's Disease Neuroimaging Initiative (ADNI) and on an external independent cohort from The National Alzheimer's Coordinating Center (NACC). The deep-learning model is accurate, achieved an area-under-the-curve (AUC) of 85.12 when distinguishing between cognitive normal subjects and subjects with either MCI or mild Alzheimer's dementia. In the more challenging task of detecting MCI, it achieves an AUC of 62.45. It is also significantly faster than the volume/thickness model in which the volumes and thickness need to be extracted beforehand. The model can also be used to forecast progression: subjects with mild cognitive impairment misclassified as having mild Alzheimer's disease dementia by the model were faster to progress to dementia over time. An analysis of the features learned by the proposed model shows that it relies on a wide range of regions associated with Alzheimer's disease. These findings suggest that deep neural networks can automatically learn to identify imaging biomarkers that are predictive of Alzheimer's disease, and leverage them to achieve accurate early detection of the disease.

Loss of Paneth cells and their antimicrobial granules compromises the intestinal epithelial barrier and is associated with Crohn's disease, a major type of inflammatory bowel disease^1-7. Non-classical lymphoid cells, broadly referred to as intraepithelial lymphocytes (IELs), intercalate the intestinal epithelium^8,9. This anatomical position has implicated them as first-line defenders in resistance to infections, but their role in inflammatory disease pathogenesis requires clarification. The identification of mediators that coordinate crosstalk between specific IEL and epithelial subsets could provide insight into intestinal barrier mechanisms in health and disease. Here we show that the subset of IELs that express γ and δ T cell receptor subunits (γδ IELs) promotes the viability of Paneth cells deficient in the Crohn's disease susceptibility gene ATG16L1. Using an ex vivo lymphocyte-epithelium co-culture system, we identified apoptosis inhibitor 5 (API5) as a Paneth cell-protective factor secreted by γδ IELs. In the Atg16l1-mutant mouse model, viral infection induced a loss of Paneth cells and enhanced susceptibility to intestinal injury by inhibiting the secretion of API5 from γδ IELs. Therapeutic administration of recombinant API5 protected Paneth cells in vivo in mice and ex vivo in human organoids with the ATG16L1 risk allele. Thus, we identify API5 as a protective γδ IEL effector that masks genetic susceptibility to Paneth cell death.

In the natural environment, we often form stable perceptual experiences from ambiguous and fleeting sensory inputs. Which neural activity underlies the content of perception and which neural activity supports perceptual stability remains an open question. We used a bistable perception paradigm involving ambiguous images to behaviorally dissociate perceptual content from perceptual stability, and magnetoencephalography to measure whole-brain neural dynamics in humans. Combining multivariate decoding and neural state-space analyses, we found frequency-band-specific neural signatures that underlie the content of perception and promote perceptual stability, respectively. Across different types of images, non-oscillatory neural activity in the slow cortical potential (<5 Hz) range supported the content of perception. Perceptual stability was additionally influenced by the amplitude of alpha and beta oscillations. In addition, neural activity underlying perceptual memory, which supports perceptual stability when sensory input is temporally removed from view, also encodes elapsed time. Together, these results reveal distinct neural mechanisms that support the content versus stability of visual perception.

OBJECTIVE:Multiple sclerosis (MS) is a debilitating neurological disease associated with a variety of psychological, cognitive, and motoric symptoms. Walking is among the most important functions compromised by MS. Dual-task walking (DTW), an everyday activity in which people walk and engage in a concurrent, discrete task, has been assessed in MS, but little is known about how it relates to other MS symptoms. Self-awareness theory suggests that DTW may be a function of the interactions among psychological, cognitive, and motor processes. METHOD/METHODS:Cognitive testing, self-report assessments for depression and falls self-efficacy (FSE), and walk evaluations [DTW and single-task walk (STW)] were assessed in seventy-three people with MS in a clinical care setting. Specifically, we assessed whether psychological factors (depression and FSE) that alter subjective evaluations regarding one's abilities would moderate the relationships between physical and cognitive abilities and DTW performance. RESULTS:DTW speed is related to diverse physical and cognitive predictors. In support of self-awareness theory, FSE moderated the relationship between STW and DTW speeds such that lower FSE attenuated the strength of the relationship between them. DTW costs - the change in speed normalized by STW speed - did not relate to cognitive and motor predictors. DTW costs did relate to depressive symptoms, and depressive symptoms moderated the effect of information processing on DTW costs. CONCLUSIONS:Findings indicate that an interplay of physical ability and psychological factors - like depression and FSE - may enhance understanding of walking performance under complex, real-world, DTW contexts.

INTRODUCTION:Diroximel fumarate (DRF) is an oral fumarate for relapsing multiple sclerosis (MS). Clinical and real-world studies of DRF have demonstrated improved gastrointestinal (GI) tolerability and low (< 1%) GI-related treatment discontinuation versus dimethyl fumarate (DMF) and high rates of treatment adherence. Our aim was to conduct a concept elicitation study to identify treatment-related concepts most meaningful to patients and to evaluate how these concepts shape the patient perspective of DRF. METHODS:In-depth qualitative interviews were conducted with patients from October to December 2020. US adults who had been prescribed DRF through routine clinical care and had taken DRF for ≥ 3 weeks in the past 6 months were eligible to participate. Semi-structured interviews explored patient perceptions on treatment selection and impact. RESULTS:Seventeen patients participated in the study. Mean (SD) age was 49.3 (12.0) years. Sixteen patients reported prior disease-modifying therapy, while 10 (58.8%) had prior DMF. DRF treatment duration ranged from ~ 6 weeks to 10 months. Four key concepts emerged: (1) overall wellness and quality of life, (2) ease of administration, (3) minimal and manageable side effects, and (4) patient optimism due to MS treatments. Mode of administration (82.4%), no/mild side effects (70.6%), convenience over injectable/infusion medications (58.8%), and effectiveness (64.7%) were cited as positive aspects of DRF treatment. Frequent dosing (52.9%) and food requirements (41.2%) were cited as negative attributes; however, 94.1% had no dietary changes since starting treatment. CONCLUSION:The patient perspective is a key aspect when considering a disease-modifying therapy for MS, given the multitude of options currently available. Overall wellness, ease of administration, and minimal and manageable side effects were DRF-related concepts most meaningful to patients on therapy. Acknowledging these patient perceptions in shared decision-making may lead to greater patient adherence and optimal treatment outcomes.