Faculty Bibliography

INTRODUCTION/BACKGROUND:Disturbances in microvascular flow dynamics are hypothesized to precede the symptomatic phase of Alzheimer's disease (AD). However, evidence in presymptomatic AD remains elusive, underscoring the need for therapies targeting these early vascular changes. METHODS:We employed a multimodal approach, combining in vivo optical imaging, molecular techniques, and ex vivo magnetic resonance imaging, to investigate early capillary dysfunction in C57BL/6-Tg(Thy1-APPSwDutIowa)BWevn/Mmjax (Tg-SwDI) mice without memory impairment. We also assessed the efficacy of carbonic anhydrase inhibitors (CAIs) in preventing capillary flow disturbances. RESULTS:Our study revealed capillary flow disturbances associated with alterations in capillary morphology, adhesion molecule expression, and amyloid beta (Aβ) load in 9- to 10-month-old Tg-SwDI mice without memory impairment. CAI treatment ameliorated these capillary flow disturbances, enhanced oxygen availability, and reduced Aβ load. DISCUSSION/CONCLUSIONS:These findings underscore the importance of capillary flow disturbances as early biomarkers in presymptomatic AD and highlight the potential of CAIs for preserving vascular integrity in the early stages of AD. HIGHLIGHTS/CONCLUSIONS:Uncovered early capillary dysfunction in a presymptomatic Alzheimer's disease (AD) mouse model. Evidence linking capillary stalls and capillary dysfunction with oxygen delivery issues in AD. Novel use of carbonic anhydrase inhibitors to prevent early capillary flow disturbances in AD.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Low sun and ultraviolet radiation (UVR) exposures have been associated with increased risk of developing pediatric-onset multiple sclerosis (MS); however, their effect on disease course has not been well characterized. We primarily investigated whether there was an association between time spent in the sun in early childhood and risk of relapse in pediatric MS. We secondarily investigated the effect of sun exposure during more recent periods on risk of relapse. METHODS:We conducted a multicenter cohort study of participants with pediatric-onset MS recruited from 18 pediatric MS clinics across the United States between November 1, 2011, and July 1, 2017. Relapses were identified prospectively after study enrollment; relapses preceding study enrollment were entered retrospectively. Time spent in the sun at various periods of life was measured using a detailed environmental questionnaire, and ambient UVR exposure was determined using zip codes. Multivariable Cox regression models were used to assess the association between time spent in the sun and UVR dose at specific periods of life and the risk of relapse. Models were adjusted for demographic, clinical, and sun exposure-related characteristics. RESULTS:= 0.04). UVR dose and time spent in the sun later in life were not significantly associated with relapse risk. DISCUSSION/CONCLUSIONS:In this large cohort study of children with MS, greater early childhood and prenatal sun exposure time was associated with lower risk of relapse. Further investigation of sun exposure at other periods is needed to better characterize its impact on disease course and guide potential future interventions.

The objective of this study was to evaluate the effect of seletracetam (SEL), a potent modulator of synaptic vesicle glycoprotein 2A (SV2A), in patients with photoparoxysmal EEG response (PPR) to intermittent photic stimulation (IPS) as proof-of-principle of efficacy in patients with epilepsy. In this multicenter, single-blind Phase II study, adults with photosensitive epilepsy, with/without concomitant antiseizure medication therapy, underwent IPS under 3 eye conditions (at eye closure, eyes closed and eyes open) after a single oral dose of placebo (day - 1) or SEL (day 1; 0.5, 1, 2, 4, 10, or 20 mg). Complete suppression was a standardized photosensitivity range reduction to 0 over ≥ 1 time points for all eye conditions. Partial suppression was a ≥ 3-point reduction over ≥ 3 testing times vs the same time points on day - 1 in ≥ 1 eye condition. In addition, pharmacokinetics and safety were assessed. Of 27 evaluable patients, 9 reentered to receive a 2nd dosing 1-6 months later, providing a total of 36 individual exposures. At all doses administered - even the lowest -, several subjects reached a complete abolishment of PPR, with a rapid onset of effect. Overall, complete abolishment of PPR was obtained in 40-71 % of the patients; the effect increasing with the dose. In terms of effective doses to suppress PPR, SEL was at least 1,500 times more potent than levetiracetam and 10-20 times more potent than brivaracetam. Adverse events of SEL, including dizziness and somnolence, were mild to moderate. Pharmacokinetics of SEL demonstrated rapid absorption and a linear dose:plasma level relationship. This proof-of-principle study demonstrates that - based on our own experience - SEL is the most potent compound ever tested in the photosensitivity model.

Cerebral arteriovenous malformations (AVMs) are congenital vascular anomalies that can lead to severe complications, including hemorrhage and neurological deficits. This study compares the outcomes of microsurgical resection and stereotactic radiosurgery (SRS) for SM grade I and II AVMs. Out of a large multicenter registry, we identified 180 matched patients with SM grade I and II AVMs treated with either microsurgical resection or SRS between 2010 and 2023. The primary outcomes were AVM obliteration rates and complications; secondary outcomes included neurological status and functional outcomes measured by the modified Rankin Scale (mRS). Propensity score matching (PSM) was utilized to ensure comparability between treatment groups. After PSM, 90 patients were allocated to each treatment group. Significant differences were observed in complete obliteration rates, with resection achieving higher rates compared to SRS in overall cases (97.8% vs. 60.0%, p < 0.001), unruptured AVMs (100% vs. 58.3%, p < 0.001), and ruptured AVMs (95.2% vs. 61.9%, p < 0.001). Functional improvement rates were similar between the groups for overall cases (67.2% in resection vs. 66.7% in SRS, p = 0.95), unruptured AVMs (55.2% in resection vs. 55.6% in SRS, p > 0.9), and ruptured AVMs (78.1% in resection vs. 74.1% in SRS, p = 0.7). Symptomatic complication rates were identical between the groups (11.1% each, p > 0.9), while permanent complication rates were comparable (6.7% in resection vs. 5.6% in SRS, p = 0.8). Resection demonstrated significantly higher complete obliteration rates compared to SRS across all cases, including unruptured and ruptured AVMs. Functional improvement rates were similar between the two treatment groups, with no significant differences in symptomatic or permanent complication rates.

Developmental and epileptic encephalopathies (DEEs) are the most severe group of epilepsies, characterized by drug-resistant seizures and developmental slowing or regression. DEEs encompass many epilepsy syndromes, although not all patients with a DEE can be classified into a specific syndrome. Our understanding of the etiologies of DEEs has been revolutionized with next-generation sequencing, with more than 900 genes implicated, in addition to structural causes. It is therefore now possible to consider precision medicine and novel therapeutic approaches for these devastating diseases with trials of repurposed and new drugs, including gene therapies. Trials are being designed to target either DEE diseases more broadly, specific DEE syndromes, or specific genetic DEEs. To serve this purpose, a clear operational definition of DEEs is needed to ensure that appropriate patients are selected for trials with precisely defined, targeted outcome measures. Herein we propose the operational definition of DEEs to set the stage for the development of DEE therapies.

This study explores the use of virtual reality (VR) as an innovative tool to enhance awareness, understanding of accessibility for persons with vision loss (VL), and acceptance. Through a VR-based workshop developed in collaboration with New York City's Department Of Transportation, participants experienced immersive simulations of VL and related immersive mobility challenges. The methodology included the development of a VR environment, simulations of vision loss, testing with the DOT team during the workshop, and an assessment of changes in participants' knowledge, confidence in addressing accessibility challenges, and overall perception through pre- and post-intervention questionnaires. Participants included urban planners, designers, and architects. Results showed a significant increase in awareness of VL-related challenges that affect design guidelines, as well as improved confidence in addressing such challenges. Participants also expressed strong support for VR as a pedagogical tool, noting its potential for reshaping professional practices, improving capacity building, and enhancing inclusive design. The study demonstrates the effectiveness of VR as an experiential learning platform, fostering empathy and a long-term commitment to integrating VL considerations into urban design. These findings highlight the transformative potential of VR in advancing equity and accessibility in urban environments.

Small-animal diffusion MRI (dMRI) has been used for methodological development and validation, characterizing the biological basis of diffusion phenomena, and comparative anatomy. The steps from animal setup and monitoring, to acquisition, analysis, and interpretation are complex, with many decisions that may ultimately affect what questions can be answered using the resultant data. This work aims to present selected considerations and recommendations from the diffusion community on best practices for preclinical dMRI of in vivo animals. We describe the general considerations and foundational knowledge that must be considered when designing experiments. We briefly describe differences in animal species and disease models and discuss why some may be more or less appropriate for different studies. We, then, give recommendations for in vivo acquisition protocols, including decisions on hardware, animal preparation, and imaging sequences, followed by advice for data processing including preprocessing, model-fitting, and tractography. Finally, we provide an online resource that lists publicly available preclinical dMRI datasets and software packages to promote responsible and reproducible research. In each section, we attempt to provide guides and recommendations, but also highlight areas for which no guidelines exist (and why), and where future work should focus. Although we mainly cover the central nervous system (on which most preclinical dMRI studies are focused), we also provide, where possible and applicable, recommendations for other organs of interest. An overarching goal is to enhance the rigor and reproducibility of small animal dMRI acquisitions and analyses, and thereby advance biomedical knowledge.

Preclinical diffusion MRI (dMRI) has proven value in methods development and validation, characterizing the biological basis of diffusion phenomena, and comparative anatomy. While dMRI enables in vivo non-invasive characterization of tissue, ex vivo dMRI is increasingly being used to probe tissue microstructure and brain connectivity. Ex vivo dMRI has several experimental advantages that facilitate high spatial resolution and high SNR images, cutting-edge diffusion contrasts, and direct comparison with histological data as a methodological validation. However, there are a number of considerations that must be made when performing ex vivo experiments. The steps from tissue preparation, image acquisition and processing, and interpretation of results are complex, with many decisions that not only differ dramatically from in vivo imaging of small animals, but ultimately affect what questions can be answered using the data. This work concludes a three-part series of recommendations and considerations for preclinical dMRI. Herein, we describe best practices for dMRI of ex vivo tissue, with a focus on image pre-processing, data processing, and comparisons with microscopy. In each section, we attempt to provide guidelines and recommendations but also highlight areas for which no guidelines exist (and why), and where future work should lie. We end by providing guidelines on code sharing and data sharing and point toward open-source software and databases specific to small animal and ex vivo imaging.

IMPORTANCE/UNASSIGNED:Classification of persons with long COVID (LC) or post-COVID-19 condition must encompass the complexity and heterogeneity of the condition. Iterative refinement of the classification index for research is needed to incorporate newly available data as the field rapidly evolves. OBJECTIVE/UNASSIGNED:To update the 2023 research index for adults with LC using additional participant data from the Researching COVID to Enhance Recovery (RECOVER-Adult) study and an expanded symptom list based on input from patient communities. DESIGN, SETTING, AND PARTICIPANTS/UNASSIGNED:Prospective, observational cohort study including adults 18 years or older with or without known prior SARS-CoV-2 infection who were enrolled at 83 sites in the US and Puerto Rico. Included participants had at least 1 study visit taking place 4.5 months after first SARS-CoV-2 infection or later, and not within 30 days of a reinfection. The study visits took place between October 2021 and March 2024. EXPOSURE/UNASSIGNED:SARS-CoV-2 infection. MAIN OUTCOMES AND MEASURES/UNASSIGNED:Presence of LC and participant-reported symptoms. RESULTS/UNASSIGNED:A total of 13 647 participants (11 743 with known SARS-CoV-2 infection and 1904 without known prior SARS-CoV-2 infection; median age, 45 years [IQR, 34-69 years]; and 73% were female) were included. Using the least absolute shrinkage and selection operator analysis regression approach from the 2023 model, symptoms contributing to the updated 2024 index included postexertional malaise, fatigue, brain fog, dizziness, palpitations, change in smell or taste, thirst, chronic cough, chest pain, shortness of breath, and sleep apnea. For the 2024 LC research index, the optimal threshold to identify participants with highly symptomatic LC was a score of 11 or greater. The 2024 index classified 20% of participants with known prior SARS-CoV-2 infection and 4% of those without known prior SARS-CoV-2 infection as having likely LC (vs 21% and 5%, respectively, using the 2023 index) and 39% of participants with known prior SARS-CoV-2 infection as having possible LC, which is a new category for the 2024 model. Cluster analysis identified 5 LC subtypes that tracked quality-of-life measures. CONCLUSIONS AND RELEVANCE/UNASSIGNED:The 2024 LC research index for adults builds on the 2023 index with additional data and symptoms to help researchers classify symptomatic LC and its symptom subtypes. Continued future refinement of the index will be needed as the understanding of LC evolves.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Sex steroid hormones have been demonstrated to affect the immune system in multiple sclerosis (MS), and puberty may trigger MS activity. We aimed to evaluate the association between menarche and disease course in pediatric MS through comparison of relapse rates across premenarche, perimenarche, and postmenarche periods. METHODS:This is a retrospective analysis of a prospectively followed female cohort with pediatric-onset MS in the US Network of Pediatric MS Centers database. Perimenarche was considered the period from 1 year before to 1 year after the estimated menarche date based on menarche integer age. Relapses were collected prospectively. Negative binomial and repeated-measures Cox regression models were used to assess the association of pubertal development stage with relapse rate, adjusted for race, body mass index, and disease-modifying therapy (DMT). RESULTS:< 0.001). DISCUSSION/CONCLUSIONS:Onset of puberty may be a time of increase in disease activity and may require consideration of a change in therapeutic approach. Menarche age was used as a surrogate for puberty, and future studies measuring sex steroid hormones may be informative.