Faculty Bibliography

INTRODUCTIONS:Excessive mechanical stress is closely associated with cell death in various conditions. Exposure of chondrocytes to excessive mechanical loading leads to a catabolic response as well as exaggerated cell death. Ferroptosis is a recently identified form of cell death during cell aging and degeneration. However, it's potential association with mechanical stress remains to be illustrated. OBJECTIVES:To identify whether excessive mechanical stress can cause ferroptosis. To explore the role of mechanical overloading in chondrocyte ferroptosis. METHODS:) mice OA model and chondrocytes cultured with high strain mechanical stress. Furthermore, the role of Piezo1 ion channel in chondrocyte ferroptosis and OA development was explored by using its inhibitor (GsMTx4) and agonist (Yoda1). Additionally, chondrocyte was cultured in calcium-free medium with mechanical stress, and ferroptosis phenotype was tested. RESULTS:Human cartilage and mouse chondrocyte experiments revealed that mechanical overloading can induce GPX4-associated ferroptosis. Conditional knockout of GPX4 in cartilage aggravated experimental OA process, while additional treatment with ferroptosis suppressor protein (FSP-1) and coenzyme Q10 (CoQ10) abated OA development in GPX4-CKO mice. In mouse OA model and chondrocyte experiments, inhibition of Piezo1 channel activity increased GPX4 expression, attenuated ferroptosis phenotype and reduced the severity of osteoarthritis. Additionally, high strain mechanical stress induced ferroptosis damage in chondrocyte was largely abolished by blocking calcium influx through calcium-free medium. CONCLUSIONS:Our findings show that mechanical overloading induces ferroptosis through Piezo1 activation and subsequent calcium influx in chondrocytes, which might provide a potential target for OA treatment.

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.

The classification of multiple sclerosis (MS) has been established by Lublin in 1996 and revised in 2013. The revision includes clinically isolated syndrome, relapsing-remitting, primary progressive and secondary progressive MS, and has added activity (i.e., formation of white matter lesions or clinical relapses) as a qualifier. This allows for the distinction between active and nonactive progression, which has been shown to be of clinical importance. We propose that a logical extension of this classification is the incorporation of additional key pathological processes, such as chronic perilesional inflammation, neuroaxonal degeneration, and remyelination. This will distinguish MS phenotypes that may present as clinically identical but are driven by different combinations of pathological processes. A more precise description of MS phenotypes will improve prognostication and personalized care as well as clinical trial design. Thus, our proposal provides an expanded framework for conceptualizing MS and for guiding development of biomarkers for monitoring activity along the main pathological axes in MS.

INTRODUCTION/BACKGROUND:The lack of ideal measurement of treatment efficacy is a well acknowledged problem in the epilepsy community, both in clinical care and clinical trials. Whilst still the current gold-standard, self-reported seizure frequency significantly underestimates the true number of seizures and does not account for any other at least equally important outcome parameters, such as neurodevelopment and cognition. With the rise of disease modifying treatments, the need for more reliable endpoints in practice and clinical trials becomes more pressing. In this paper we assembled an expert panel to discuss the nature of these needs, current limitations, and obstacles based on a survey amongst these experts who were queried about the most important issues regarding the use of electroencephalography (EEG) parameters as endpoints in clinical drug and device development. METHODS:A structured survey was sent to a group of experts in the design and conduct of epilepsy trials in adults and children. This was followed by a virtual in-person meeting discussing the results of the trial and identifying a list of most important issues. RESULTS:Six clinical trialists and 5 individuals from pharmaceutical companies returned the survey containing 14 questions, and 8 clinical trialists and 10 pharma-representatives attended the meeting. Three main issues were identified (1) lack of accuracy of seizure diaries due to nocturnal seizures, subtle motor seizures, impairment of consciousness and lack of awareness of the seizure by the patient (2) inter-rater variability of EEG assessment (3) lack of standardization regarding definition(s) of seizures (clinical and electrographic), EEG recording methods and EEG data management. Recommended solutions included (1) validation of EEG parameters as biomarkers and use of wearables (2) development of a manual that describes EEG rating criteria, protocol for validation by > 1 central reader and use of a resolution of disagreements reporting template (3) standardization of EEG recording, data management and reporting. DISCUSSION & CONCLUSION/CONCLUSIONS:Current developments in research and technology seem promising to advance the use of EEG parameters as potential endpoints and offer partial solutions to the current needs. However, continuous, focused and collaborative efforts of all stakeholders (academia, industry and regulatory agencies) are needed to formulate guidelines, validate emerging technologies and approve them for use in trials. It is the intent of this opinion "position paper" to stimulate those efforts.

BACKGROUND/UNASSIGNED:Botulinum neurotoxin (BoNT) injection is an established therapy for limb spasticity and focal limb dystonia. Comparative benefits of injection guidance procedures have not been rigorously studied. OBJECTIVES/UNASSIGNED:We compared 2 targeting techniques for onabotulinumtoxin-A (onabotA) injection for the treatment of focal hand dystonia and upper limb spasticity: electrophysiologic guidance using electrical stimulation (E-stim) and ultrasound (US). METHODS/UNASSIGNED:This was a 2-center, randomized, crossover, assessor-blinded trial. Participants with focal hand dystonia or upper limb spasticity, on stable onabotA therapy for at least 2 previous injection cycles, were randomly assigned to either E-stim or US with crossover at 3 months. The primary outcome was improvement in dystonia or spasticity severity on a visual analog scale (VAS; 0-100) measured 1 month after each injection. The secondary outcome was participant discomfort assessed on a VAS. Repeated-measures analysis of covariance was used with linear mixed-model covariate selection. RESULTS/UNASSIGNED:A total of 19 participants (13 men) completed the study, 10 with upper limb spasticity and 9 with dystonia. Benefit was equivalent between the 2 techniques (VAS least-square mean [LSmean] 51.5 mm with US and 53.1 with E-stim). E-stim was perceived as more uncomfortable by participants (VAS LSmean 34.5 vs. 19.9 for E-stim and US, respectively). Procedure duration was similar with the 2 procedures. There were no serious adverse events related to either approach. CONCLUSIONS/UNASSIGNED:US and E-Stim localization guidance techniques provide equivalent efficacy in onabotA injections for spasticity and dystonia. US guidance injections are more comfortable for participants. Both techniques are effective guidance methods, with US potentially preferable based on participant comfort.

BACKGROUND:Stroke mimics are non-vascular conditions that present with acute focal neurological deficits, simulating an acute ischemic stroke. Susumber berry (SB) toxicity is a rare cause of stroke mimic with limited case reports available in the literature. OBJECTIVES/OBJECTIVE:We report four new cases of SB toxicity presenting as stroke mimic, and we performed a systematic review. METHODS:MEDLINE/EMBASE/WoS were searched for "susumber berries," "susumber," or "solanum torvum." RESULTS:531 abstracts were screened after removal of duplicates; 5 articles and 2 conference abstracts were selected describing 13 patients. A total of 17 patients who ingested SB and became ill were identified, including our 4 patients. All but one presented with acute neurologic manifestation; 16 (94%) presented with dysarthria, 16 (94%) with unstable gait, 8 (47%) with nystagmus/gaze deviation, 10 (59%) with blurry vision, and 5 (29%) with autonomic symptoms. Six (35%) required ICU admission, and 3 (18%) were intubated. Fourteen (82%) had a rapid complete recovery, and 3 were hospitalized up to 1 month. CONCLUSIONS:SB toxicity can cause neurological symptoms that mimic an acute stroke typically with a posterior circulation symptom complex. Altered SB toxins (from post-harvest stressors or temperature changes) might stimulate muscarinic/nicotinic cholinergic receptors or inhibit acetylcholinesterase, causing gastrointestinal, neurological, and autonomic symptoms. In cases of multiple patients presenting simultaneously to the ED with stroke-like symptoms or when stroke-like symptoms fail to localize, a toxicological etiology (such as SB toxicity) should be considered.

BACKGROUND AND OBJECTIVES/OBJECTIVE:To report the tolerability and efficacy of olaparib with temozolomide (TMZ) for glioma. METHODS:Single-center retrospective series of patients with glioma treated with olaparib/TMZ from September 2018 to December 2021. RESULTS:-wildtype gliomas (0/3). Progression-free survival was 7.8, 1.3, and 2.0 months, respectively. DISCUSSION/CONCLUSIONS:-mutant grade 2-3 gliomas with encouraging progression-free survival and manageable toxicity. This supports a prospective trial of olaparib/TMZ for this population. CLASSIFICATION OF EVIDENCE/METHODS:This case series provides Class IV evidence that treatment with olaparib/TMZ may result in radiographic response in patients with glioma.

While several studies have attributed the development of tumour-associated seizures to an excitatory-inhibitory imbalance, we have yet to resolve the spatiotemporal interplay between different types of neuron in glioma-infiltrated cortex. Herein, we combined methods for single unit analysis of microelectrode array recordings with wide-field optical mapping of Thy1-GCaMP pyramidal cells in an ex vivo acute slice model of diffusely infiltrating glioma. This enabled simultaneous tracking of individual neurons from both excitatory and inhibitory populations throughout seizure-like events. Moreover, our approach allowed for observation of how the crosstalk between these neurons varied spatially, as we recorded across an extended region of glioma-infiltrated cortex. In tumour-bearing slices, we observed marked alterations in single units classified as putative fast-spiking interneurons, including reduced firing, activity concentrated within excitatory bursts and deficits in local inhibition. These results were correlated with increases in overall excitability. Mechanistic perturbation of this system with the mTOR inhibitor AZD8055 revealed increased firing of putative fast-spiking interneurons and restoration of local inhibition, with concomitant decreases in overall excitability. Altogether, our findings suggest that diffusely infiltrating glioma affect the interplay between excitatory and inhibitory neuronal populations in a reversible manner, highlighting a prominent role for functional mechanisms linked to mTOR activation.

OBJECTIVES/OBJECTIVE:Long-term video-electroencephalographic monitoring (LTVEM) represents the gold-standard method to evaluate whether events represent electrographic seizures, but limited work has evaluated the quality of inpatient event capture. We evaluated the frequency of audiovisual factors impairing the ideal electroclinical correlation of seizure-like episodes during LTVEM. METHODS:We retrospectively reviewed consecutive inpatient LTVEM studies (11/2019-12/2019) from three academic epilepsy centers. We evaluated all pushbutton events for audiovisual characteristics such as whether the event was narrated, whether the patient was blocked on camera, and what diagnostic challenges impaired the electroencephalographer's ability to understand either the reason the event button was pushed or clinical semiology ("electroclinical correlation"). We determined the percent of events and studies with each outcome. RESULTS:There were 154 studies with 520 pushbutton events. The pushbutton was most commonly activated by patients (41%), followed by nurses (31%) or family (17%). Twenty-nine percent of events represented electrographic seizures, and 78% occurred in the Epilepsy Monitoring Unit. The reason for the push was not stated in 45% of events, and inadequate narration impaired electroclinical correlation in 19% of events. At least one relevant part of the patient's body was blocked during 12% of events, but this impaired electroclinical correlation in only 1% of events. There was at least one factor impairing electroclinical correlation in 21% of events, most commonly due to incomplete narration (N = 99), lights off (N = 15), or blankets covering the patient (N = 15). At least one factor impaired electroclinical correlation for any event in 36% of studies. CONCLUSION/CONCLUSIONS:Audiovisual factors impairing the electroencephalographer's ability to render an electroclinical correlation were common, particularly related to inadequate narration from bedside observers to explain the reason for pushing the button or event semiology. Future efforts to develop targeted countermeasures should address narration challenges and improve inpatient seizure monitoring quality metrics.