bluuebunny/crossref_metadata_2025 huggingface dataset:
Seasonal and spatial variations in the diet of the Egyptian mongoose in its north-eastern Iberian range edge
Authors: Descalzo Esther , Díaz-Ruiz Francisco , Delibes-Mateos Miguel , Jiménez José , Ferreras Pablo
Published: June 2023

The Egyptian mongoose (Herpestes ichneumon) is considered a generalist and opportunistic predator whose European distribution is restricted to Iberia. However, all the previous studies on the Egyptian mongoose’s diet in the Iberian Peninsula have been performed in Portugal and Doñana National Park (southwestern Spain), covering a small region of the species’ current distribution. To improve the knowledge on the trophic ecology of the species, we estimated the feeding habits of the Egyptian mongoose in central Spain, its north-eastern range edge. Our study was based on the analysis of (1) scats (n = 251) and (2) stomach contents (n = 32); samples were collected between 2018 and 2022. We calculated the relative frequency of occurrence (%RFO) and the percentage consumed biomass (%CB) for 12 food groups across central Spain and we assessed site-seasonal variations in diet composition in three study areas. We also estimated rabbit densities in the three study areas to assess the effect of rabbit abundance on mongoose diets. Overall, our results showed that European rabbits were the group with highest %CB (30.7%) in the diet of the Egyptian mongoose, followed by reptiles (19.9%) and small mammals (19.9%). In the intensively studied areas, the %CB of rabbits was the highest in the area with the highest abundance of this prey, whereas reptiles had the highest %CB in the area with the lowest availability of rabbits. Diet diversity (Shannon index) varied between 1.73 and 2.47 in those areas and was inversely related to the availability of rabbits. Our results confirm the dietary flexibility of this predator that adapts its diet to the relative availability of different prey species in different habitats.
One-sided invertibility of Toeplitz operators on the space of all holomorphic functions on finitely connected domains
Authors: Jasiczak M.
Published: June 2023

We prove that if the symbol of a Toeplitz operator acting on the space of all holomorphic functions on a finitely connected domain is non-degenerate and vanishes then the range of this operator is not complemented. As a result, we obtain that a Toeplitz operator on the space of all holomorphic functions on finitely connected domains is left invertible if and only if it is an injective Fredholm operator. Also, such an operator is right invertible if and only if it is a surjective Fredholm operator.
Dynamical modelling of boom tower crane rigging systems: model selection for construction
Authors: Johns Brandon , Abdi Elahe , Arashpour Mehrdad
Published: June 2023

Accurate dynamical models are imperative to the development of accurate monitoring and control systems, which are foundational to safety in construction and infrastructure projects. However, the highly coupled non-linear dynamics of crane systems requires the application of many simplifying assumptions to the dynamical crane model. To achieve accurate control, simplifications should yield minimal error in modelled behaviour for maximal reduction in model complexity. However, limited information is available on the situational suitability of different combinations of simplifications to construction tower crane models. This paper informs designers of the optimal dynamical models to represent boom tower cranes, with respect to the crane characteristics and selection criteria. The optimal models are determined though the comparison of ten 2D and 3D dynamical models in representation of three variations of boom tower crane that are commonly deployed on construction sites. The comparison includes analysis of over 100 simulations and experimentation. The value of the presented optimal model selection framework is in facilitating systems designers to develop accurate crane monitoring and control systems.
Medical students maintain their humanistic and patient-centred vocation throughout Medicine Degree in Spain: a study based on narratives
Authors: de Rivera Atienza Víctor Afán , Gutiérrez-Misis Alicia , Alfonso Augusto César Blanco , Rodrigo José María Vizcaíno Sánchez , Arribas José María , López Natividad Puche , Castell-Alcalá María Victoria , Ramos María Teresa Blanco , Goñi Jacinta Landa , Pérez María Dolores Cano , Gutiérrez María Fátima Prado , Panadés Rosa María García , Gonzalez-Lopez Esteban , Gijón-Conde Teresa
Published: June 2023

Narrative medicine has great educational potential in the degree of medicine. This study explores for the first time the use of narrative medicine in relation to longitudinal evolution of medical vocation for the same group of students. In the context of the Degree in Medicine at the Universidad Autónoma de Madrid (Spain), students wrote narratives about what it meant to them to be a doctor at the beginning and end of their studies. The narratives of 338 students of the academic years 2012/13–2017/18 and 2013/14–2018/19 were analysed and compared. Students mostly pursued a degree in medicine on account of humanistic motivations, which are reinforced throughout their degree. In contrast, up to 10% of students reference to have experienced vocational crises and suffered frustration, with up to 25% of the references pertaining to having made significant sacrifices. Students maintain and evolve their humanistic, patient-centred vision throughout their degree studies, despite the difficulties they appear to encounter. We suggest that efforts must be made to include more humanistic perspectives in the medical degree to keep this trend, which may improve both the educational experience created in universities and the health care given to patients.
Quantitative Assessment of Ultraviolet-Induced Erythema and Tanning Responses in the Han Chinese Population
Authors: Ma Yanyun , Tan Yimei , Hu Yue , Pu Weilin , Xu Jinhua , Jin Li , Wang Jiucun
Published: June 2023

Ultraviolet radiation (UVR) can induce erythema and tanning responses with strong diversity within and between populations, but there were no precise method for evaluating the variation in these responses. In this study, we assessed the time course of ultraviolet (UV)-induced responses based on the erythema index (EI) and melanin index (MI) over 14 consecutive days in a pilot cohort study (N = 31). From safety evaluations, we found that no skin blisters occurred at a UV dosage of 45 mJ/cm2, but there were significant skin reactions. Regardless of UV dosage, the measurements and variances of EI peaked on day 1 after UV irradiation, and those of MI peaked on day 7. Dose–response curves, including erythema dose–response (EDR) and melanin dose–response (MDR), could measure UV-induced phenotypes sensitively but more laboriously. As an alternative, we directly represented the UV-induced erythema and tanning responses using the erythema increment (ΔE) and melanin increment (ΔM). We found that ΔE and ΔM at 45 mJ/cm2 significantly correlated with erythema dose–response (EDR) (R2 > 0.9) and melanin dose–response (MDR) (R2 > 0.9), respectively. Therefore, ΔE and ΔM on day 1 and day 7 after UV irradiation at a dosage of 45 mJ/cm2 might be ideal alternative measures for assessing individual erythema and tanning responses. Then, a second cohort (N = 664) was recruited to validate the UV-induced phenotypes, and, as expected, the results of the two cohorts were in agreement. Therefore, we developed a simplified and precise method to quantify the UV-induced erythema response and tanning ability for the Han Chinese population.
IoT and radio telemetry based wireless engine control and real-time position tracking system for an agricultural tractor
Authors: Shrivastava Prateek , Tewari V. K. , Gupta Chanchal , Singh Gajendra
Published: June 2023

Internet of Things (IoT) has presented a new scope in the field of Precision Agriculture. With the application of cloud computing and WiFi-based long-distance network in IoT, it is possible to connect the farmers of rural areas effectively and harness the benefit of its advancement. In the present research work, an IoT-based scalable network architecture has been designed for two capabilities 1. For starting and stopping the tractor engine from a remote location and 2. For real-time tracking of the position and monitoring the engine status on a developed website. The developed system consists of the on-board unit (OBU), web server, and google map-based web application. The OBU consists of the Engine Control Sub Unit (ECSU) along with a GPS tracking sub unit for presenting real-time information on the developed web application. The ECSU consists of an RF-based wireless transmitting and receiving system to start and stop the remotely situated tractor engine. As the tractor engine starts it automatically powers up the GPS device for acquiring real-time information i.e. Longitude, Latitude, Time, speed, and Date from satellites, and sends it to the OBU. The Raspberry Pi-3 which has been used as the central processing unit in OBU, gathers both position and engine information and processes it after that sends it to the webserver, where these data are stored in the database of the web server and can be retrieved as a request for position browsing on the map. Finally, a web application was created using Python, language and also embedded with Google Map to retrieve and display real-time information. The developed system enables tractor owners to monitor the real-time position and status of the engine of their targeted tractor on Google Map. The developed system was found to be very simple and can be used by skilled farmers as well.
Use of whole genome sequencing to determine the genetic basis of visceral myopathies including Prune Belly syndrome
Authors: Geraghty Robert M. , Orr Sarah , Olinger Eric , Neatu Ruxandra , Barroso-Gil Miguel , Mabillard Holly , Consortium Genomics England Research , Wilson Ian , Sayer John A.
Published: June 2023

Objectives/aims

The visceral myopathies (VM) are a group of disorders characterised by poorly contractile or acontractile smooth muscle. They manifest in both the GI and GU tracts, ranging from megacystis to Prune Belly syndrome. We aimed to apply a bespoke virtual genetic panel and describe novel variants associated with this condition using whole genome sequencing data within the Genomics England 100,000 Genomes Project.

Methods

We screened the Genomics England 100,000 Genomes Project rare diseases database for patients with VM-related phenotypes. These patients were screened for sequence variants and copy number variants (CNV) in ACTG2, ACTA2, MYH11, MYLK, LMOD1, CHRM3, MYL9, FLNA and KNCMA1 by analysing whole genome sequencing data. The identified variants were analysed using variant effect predictor online tool, and any possible segregation in other family members and novel missense mutations was modelled using in silico tools. The VM cohort was also used to perform a genome-wide variant burden test in order to identify confirm gene associations in this cohort.

Results

We identified 76 patients with phenotypes consistent with a diagnosis of VM. The range of presentations included megacystis/microcolon hypoperistalsis syndrome, Prune Belly syndrome and chronic intestinal pseudo-obstruction. Of the patients in whom we identified heterozygous ACTG2 variants, 7 had likely pathogenic variants including 1 novel likely pathogenic allele. There were 4 patients in whom we identified a heterozygous MYH11 variant of uncertain significance which leads to a frameshift and a predicted protein elongation. We identified one family in whom we found a heterozygous variant of uncertain significance in KCNMA1 which in silico models predicted to be disease causing and may explain the VM phenotype seen. We did not find any CNV changes in known genes leading to VM-related disease phenotypes. In this phenotype selected cohort, ACTG2 is the largest monogenic cause of VM-related disease accounting for 9% of the cohort, supported by a variant burden test approach, which identified ACTG2 variants as the largest contributor to VM-related phenotypes.

Conclusions

VM are a group of disorders that are not easily classified and may be given different diagnostic labels depending on their phenotype. Molecular genetic analysis of these patients is valuable as it allows precise diagnosis and aids understanding of the underlying disease manifestations. We identified ACTG2 as the most frequent genetic cause of VM. We recommend a nomenclature change to ‘autosomal dominant ACTG2 visceral myopathy’ for patients with pathogenic variants in ACTG2 and associated VM phenotypes.
The effectiveness and externality of China’s outward foreign direct investment policy
Authors: Liu Kai , Zhu Jiayi , Iqbal Badar , Hao Yating
Published: June 2023

This paper uses the China Foreign Investment Country-Oriented Industry Catalog as a policy shock to study the effectiveness and externality effect of China's OFDI incentive policy through the RD and PSM-DID model correspondingly. The results show that OFDI encouragement policy can effectively promote enterprises to carry out foreign direct investment. This also has certain externalities that (1) firms participate in OFDI, the promotion of productivity is not significant in the short term, but in the long term the promotion effect increases with time; (2) compared with non-policy-driven OFDI, policy-driven OFDI is more effective; (3) the externality effect show strong heterogeneity on level of the host country’s technology, the absorption capacity of home-based firms, and ownership of firms.
The impact of technological innovation on occupational insertion: a case study in Brazil
Authors: Freitas Alan Araújo
Published: June 2023

This article (Special thanks to the editors of Discover Global Society magazine, Dr. Rajendra Baikady and Dr. Akshay Dhavale, and the anonymous referees for the article) analyzes the impact of technological innovation on occupational integration, using Brazil as a case study. The Brazilian example is evaluated as an illustration of how change promoted by innovation occurs, as well as its effects and consequences for individuals, positions, and occupations. The old and feared possibility of replacing humans with machines is discussed in light of the renewed fear caused by recent developments in artificial intelligence and how they may impact employment in different parts of the world. The study uses cohort analyses, occupational classes, and their respective productive sectors to provide empirical evidence for its arguments. Based on a historical-statistical analysis of a given social space, the study defends the hypothesis that the change resulting from technological innovation in the way goods and services are produced has not increased unemployment. However, it did contribute to the decline of the old middle class and the rise of a new middle class. It was not rural and urban workers who were replaced by machines. Instead, rural and urban smallholders found it difficult to compete with larger organizations that had already established themselves as modern enterprises. These former self-employed or smallholders with few employees changed occupations, and this trend was reproduced in the new generation, leading to a decline in the number of petty bourgeoisie and a concomitant increase in the occupational class called non-manual routine workers.
Propagation of chaos and large deviations in mean-field models with jumps on block-structured networks
Authors: Dawson Donald A. , Sid-Ali Ahmed , Zhao Yiqiang Q.
Published: June 2023

A system of interacting multi-class finite-state jump processes is analyzed. The model under consideration consists of a block-structured network with dynamically changing multi-color nodes. The interactions are local and described through local empirical measures. Two levels of heterogeneity are considered: between and within the blocks where the nodes are labeled into two types. The central nodes are those connected only to nodes from the same block, whereas the peripheral nodes are connected to both nodes from the same block and nodes from other blocks. Limits of such systems as the number of nodes tends to infinity are investigated. In particular, under specific regularity conditions, propagation of chaos and the law of large numbers are established in a multi-population setting. Moreover, it is shown that, as the number of nodes goes to infinity, the behavior of the system can be represented by the solution of a McKean–Vlasov system. Then, we prove large deviations principles for the vectors of empirical measures and the empirical processes, which extends the classical results of Dawson and Gärtner (Stochastics20, 1987) and Léonard (Ann. Inst. H. Poincaré Prob. Statist.31, 1995).
F.1 DNA methylome profiling identifies stability of IDH mutations throughout glioma evolution
Authors: Voisin MR , Gui C , Patil V , Gao A , Zadeh G
Published: June 2023

Background: Isocitrate dehydrogenase (IDH) mutation status is a key diagnostic and prognostic feature of gliomas. There are conflicting reports regarding the stability of IDH mutations throughout glioma evolution and treatment. Here, we provide an institutional experience of patients with conflicting IDH mutation status longitudinally in order to determine if IDH mutation status changes over time. Methods: We retrospectively identified patients from 2009-2018 with immunohistochemistry (IHC)-recorded IDH mutation status discrepancies longitudinally. Archived frozen tissue samples were analyzed using methylation profiling, Sanger sequencing, and droplet digital PCR (ddPCR). Results were compared to the IHC-reported IDH mutation status. Results: We reviewed 1491 archived glioma samples including 91 patients with multiple tumour samples collected longitudinally. In all instances of IDH mutation discrepancy, we found reasonable explanations through multi-platform profiling that resolved the discrepancies. This included the presence of non-canonical IDH2 mutations identified through Sanger sequencing and perilesional tumour samples or reactive brain tissue identified through methylation profiling. Conclusions: Our findings support the hypothesis that IDH mutations occur early in gliomagenesis and are stable throughout glioma treatment and evolution. Our study highlights the importance of accurate surgical sampling and the role of DNA methylome profiling in diagnostically uncertain cases for integrated pathological and molecular diagnosis.
P.001 Application of low-intensity transcranial focused unltrasound to the hippocampus in Alzheimer’s Disease
Authors: Chung Y , Song I , Jeong H
Published: June 2023

Background: The purpose of this study was to evaluate the safety and efficacy of low-intensity tFUS under the threshold for BBB disruption in patients with AD. In addition, we assessed changes in the regional cerebral metabolic rate of glucose (rCMRglu) using F-18 fluoro-2-deoxyglucose positron emission tomography (FDG-PET) and cognitive function after tFUS. Methods: Eight AD patients were recruited. We applied low-intensity tFUS to the right hippocampus for 3 minutes using an image-guided tFUS system. For multi-modal neuroimaging guidance, MRI and CT data were spatially co-registered using the maximization of normalized mutual information. The subjectspecific coordinates of the hippocampus in the right hemisphere were identified as the tFUS target location. Results: Radiological evidence of contrast enhancement associated with BBB opening was not found in neither the visual inspection nor the ICA of the DCE-MRI data. No adverse events were observed during the hospitalization and follow-up outpatient visits for 5 to 24 months. The immediate recall and recognition memory on the SVLT were significantly improved after the sonication. The PET analysis showed the increased level of rCMRglu in the right hippocampus. Conclusions: Application of low-intensity tFUS to the hippocampus with MB did not open blood brain barrier but increased hippocampal glucose metabolism and memory function.
P.015 Preventive treatment with eptinezumab in patients with a dual diagnosis of chronic migraine and medication-overuse headache: subgroup analysis of PROMISE-2
Authors: Marmura MJ , Diener H , Cowan RP , Starling AJ , Hirman J , Brevig T , Cady R , Yeats A
Published: June 2023

Background: This post hoc analysis of the PROMISE-2 data provides an assessment of the total preventive migraine efficacy of eptinezumab over 24 weeks in patients with a dual diagnosis of chronic migraine (CM) and medication overuse headache (MOH). Methods: PROMISE-2 was a double-blind, placebo-controlled, phase 3 study of eptinezumab (NCT02974153) over 24 weeks. Endpoints analyzed here include changes in MMDs, changes in monthly days of AHM use (total and class-specific), percentage of patients below thresholds for CM and MOH, and assessments patient-reported outcomes (PROs). Results: 40.2% patients with CM also had a diagnosis of MOH at baseline. Mean changes from baseline in MMDs during Weeks 1–12 were -8.4 and -8.6 in eptinezumab 100 mg and 300 mg treatment groups, respectively (vs 16.7 at baseline), compared with -5.4 in the placebo group (P<0.0001 vs placebo for both doses). Total monthly AHM use also decreased with eptinezumab. For all 24 weeks, 51.1% (100 mg) and 54.4% (300 mg) of eptinezumab-treated patients were below the ICHD thresholds for diagnosis of CM, compared with 32.4% of patients receiving placebo. Conclusions: This subgroup analysis of patients with a dual diagnosis of CM and MOH suggests that eptinezumab treatment resulted in greater improvements overall compared with placebo.
P.017 Convergent and contrasting modulation of saccade and pupil responses by several neurodegenerative diseases during free viewing of video clips
Authors: Riek HC , White BJ , Brien DC , Coe BC , Huang J , Abrahao A , Black SE , Borrie M , Finger E , Fischer CE , Frank AR , Freedman M , Grimes DA , Jog M , Kumar S , Kwan D , Lang AE , Lawrence-Dewar JM , Marras C , Masellis M , Pasternak SH , Pollock BG , Rajji TK , Seitz DP , Shoesmith C , Steeves TD , Tan B , Tang-Wai DF , Tartaglia C , Turnbull J , Zinman L , Investigators DP Munoz ONDRI
Published: June 2023

Background: Saccade and pupil responses are potential neurodegenerative disease biomarkers due to overlap between oculomotor circuitry and disease-affected areas. Instruction-based tasks have previously been examined as biomarker sources, but are arduous for patients with limited cognitive abilities; additionally, few studies have evaluated multiple neurodegenerative pathologies concurrently. Methods: The Ontario Neurodegenerative Disease Research Initiative recruited individuals with Alzheimer’s disease (AD), mild cognitive impairment (MCI), amyotrophic lateral sclerosis (ALS), frontotemporal dementia, progressive supranuclear palsy, or Parkinson’s disease (PD). Patients (n=274, age 40-86) and healthy controls (n=101, age 55-86) viewed 10 minutes of frequently changing video clips without instruction while their eyes were tracked. We evaluated differences in saccade and pupil parameters (e.g. saccade frequency and amplitude, pupil size, responses to clip changes) between groups. Results: Preliminary data indicates low-level behavioural alterations in multiple disease cohorts: increased centre bias, lower overall saccade rate and reduced saccade amplitude. After clip changes, patient groups generally demonstrated lower saccade rate but higher microsaccade rate following clip change to varying degrees. Additionally, pupil responses were blunted (AD, MCI, ALS) or exaggerated (PD). Conclusions: This task may generate behavioural biomarkers even in cognitively impaired populations. Future work should explore the possible effects of factors such as medication and disease stage.
P.019 Safe prescribing of antipsychotic drugs in the elderly - Parkinson Disease
Authors: Wile D , Penner LJ
Published: June 2023

Background: The Canadian Guideline for Parkinson Disease (PD) indicates clozapine and quetiapine are considered the only safe antipsychotics for people with PD, to avoid potentially exacerbating motor symptoms. In response to safety events in our centre, we explore contraindicated antipsychotic prescriptions being administered to hospital inpatients with PD to determine common factors and develop approaches to prevent future occurrences. Methods: Following a privacy impact analysis, the Interior Health Quality Improvement & Patient Safety Office identified inpatients at Kelowna General Hospital, between December 2018 and June 2021, with a coded diagnosis of PD. Pharmacy medication order and dispensing data were cross-referenced to determine patients exposed to a contraindicated antipsychotic for further chart analysis. Results: Of the 140 admissions with a PD diagnosis, 17 had at least one contraindicated antipsychotic prescribed or dispensed (12.1%). Loxapine (7) and haloperidol (6) were the most frequently prescribed. This occurred despite a diagnosis of PD being noted on admission in 14 cases, and 13 cases were known to be taking levodopa. Conclusions: These results demonstrate additional safety measures are needed to reduce the frequency of contraindicated antipsychotic prescriptions in this population. We propose developing a stepwise plan for behaviour de-escalation and pharmacological management.
P.028 Is there utility in duplicating antibody testing for autoimmune encephalitis? A comparison of results obtained from Mayo and Mitogen Dx
Authors: Gutierrez S , Roberts J , Yaraskavitch M , Hahn C
Published: June 2023

Background: Autoantibody testing for suspected autoimmune encephalitis (AIE) in Alberta is commonly performed by Mitogen Dx (MDx) using cell-based assays (CBAs) for cell surface antibodies and line immunoassay (LA) for intracellular antibodies without confirmatory tissue immunofluorescence/immunohistochemistry (TIFF/IHC). Duplicate testing is often sent to Mayo Clinic (MC) verify, resulting in increased costs. Methods: Antibody panel results were obtained for all patients who had testing sent to both MC and MDx from adult hospitals in Calgary between 2018 and 2020. Positive antibodies were evaluated to be pathogenic/non-pathogenic by chart review and expert consensus. Results: Thirty-four individuals had antibody panels completed at both labs. Overall agreement (positive/negative panel) was fair (κ = 0.24, p =.08), even after excluding low-titre GAD65 antibodies through MC (n=9, 26.5%). MDx reported more non-pathogenic serum results, including: anti-SOX1 (n=3), anti-NMDAR (n=2) and anti-GABA(B)R (n=1). All pathogenic antibodies (n=3) were positive in both laboratories. Conclusions: No new pathogenic antibodies were identified by sending duplicate testing to MC; however, a larger number of non-pathogenic antibodies were reported by MDx, likely due to lack of confirmatory TIFF/IHC. Antibody testing for AIE should be done in labs performing confirmatory TIFF/IHC on all CBA/LA results to avoid unnecessary investigations and/or treatments.
P.032 Using clinical MRI scans for research purposes: a preliminary feasibility study
Authors: Parker A , Henri-Bhargava A , Gawryluk J
Published: June 2023

Background: This project aims to bridge the gap between clinical data being collected at a local hospital to be used for research. Methods: 1.5T high-resolution anatomical MRI scans were collected from ten participants who were already undergoing clinical, imaging, and neurological assessment as part of their standard-of-care. Additional statistical models were used to examine the relationship between grey matter (using voxel-based morphometry [VBM]) and scores on the Toronto Cognitive Assessment (TorCA). Results: There was a lack of consistency in MRI scanning protocols and inconsistent reporting of clinical and neuropsychological data across participants. No significant relationship was found using the p-corrected images at p < 0.05. When viewing uncorrected images at a threshold of p < 0.001, we found a significant positive correlation between TorCA scores in the areas of the bilateral superior frontal gyrus, frontal pole, brain stem, and left putamen. Conclusions: Although no significant relationship was found between VBM metrics and TorCA scores, this project represents a crucial step in connecting health research with clinical practice where neuroimaging and neuropsychological assessments are already being collected. This project also informed our research team of areas that are needing to be streamlined and operationalized in future strategies for data collection and input.
P.056 Dual-energy CT for differentiating intracerebral hemorrhage from Contrast Extravasation after Acute Ischemic Stroke Intervention (DECT-ICH)
Authors: Siddiqi A , Trivedi A , Alcock S , Shankar J
Published: June 2023

Background: Thrombolysis (tPA) and endovascular thrombectomy (EVT) are interventions for acute ischemic stroke (AIS) that can be accompanied by intracerebral hemorrhage (ICH), which can alter the patient’s management, or contrast extravasation (CE), which is relatively benign. Previous retrospective studies have shown that dual-energy CT (DECT) is significantly more accurate for differentiating ICH from CE compared to conventional, single-energy CT (SECT). We are performing a prospective study to investigate this question. Methods: Our primary outcome is the sensitivity and specificity of DECT in differentiating ICH from CE. In AIS patients who receive intervention, we will be performing a DECT scan at the same time as the standard-of-care SECT scan at 24 hours post-intervention. In patients who have a hyperdensity on CT, a repeat scan will be done at 72-hours, which will be used as the gold-standard to determine if the hyperdensity was ICH or CE. Results: We expect that DECT will be significantly more sensitive and specific for differentiating ICH from CE compared to SECT. Conclusions: This study will determine if DECT is superior to SECT in differentiating ICH from CE, validate the use of DECT in AIS patients who receive intervention, and potentially change the imaging paradigm for acute stroke in the future.
P.064 Enhancing the neuroprotective properties of edaravone using glutathione nanogel as a promising carrier for brain drug delivery in transient global ischemia in a rodent model
Authors: Hosseini M , Bijani S
Published: June 2023

Background: Edaravone (EDV) is an antioxidant that scavengs ROS, which is known to associate with pathophysiology of ischemic stroke. Low stability and bioavailability are major EDV drawbacks. Decorating nanogel surface with glutathione to target brain tissue was performed to optimize drug delivery. Methods: Nano vehicle characterization was assessed with FT-IR and HNMR. Images from the surface of nano vehicle was captured by AFM and TEM instruments. After development of mPEG-b-PLGA EDV nano particles, their effect on biochemical factors including malondialdehyde and protein carbonyl level was measured on Wistar rats under global ischemia. The level of GSH and FRAP were also measured. Results: The Size (199 nm, hydrodynamic diameter) and zeta potential (-25 mV) of optimum formulation was assessed and the calibration curve in deionized water was created at 244 nm. In-vitro drug release profile depicted a sustained release process. EDV and glutathione presence in one vehicle simultaneously, resulted in elevated spatial memory and learning along with cognitive function. In addition, significantly lower MDA and PCO, and higher level of neural GSH and FRAP were observed. Conclusions: The developed mPEG-b-PLGA EDV nanogel can be a suited vehicle for brain drug delivery of EDV, while managing to minimize the biochemical and pathophysiological alterations in ischemic-like disorder.
P.069 Is 4 days enough? an investigation into short admissions to the Epilepsy monitoring unit
Authors: Chahrour M , Webster R , Reddy D , Dehnoei S , Healy S , Muir K
Published: June 2023

Background: The Epilepsy Monitoring Unit (EMU) plays a crucial role in a patient’s diagnosis and management for seizures and epilepsy. The duration of stay required to obtain adequate information is not clear, especially in the pediatric population. In this study, we examine whether a one to four day length of stay in the EMU is sufficient to obtain the necessary information. Methods: Retrospective review of 522 admissions (2014-2021). Included any patient admitted to CHEO’s EMU for any length of time. Results: The average admission was 1.75 days with 35.7% of patients requiring repeat EMU visits. Through a binary logistic regression, we show that a previous diagnosis of refractory seizures increases the chance of readmission to the EMU. However, a diagnosis of refractory seizures is also associated with a higher chance of achieving admission goals. While other factors including seizure type, weaning of meds, goals of admission, age, and gender have no influence on likelihood of readmission or achieving admission goals. Conclusions: This study indicates that having a short admission for EMU monitoring is sufficient to capture enough data to achieve admission goals in the pediatric population.
P.070 Serial Neurological Assessment in Pediatrics (SNAP) compared to the Glasgow Coma Scale (GCS) in PICU
Authors: Foster L , Martin D , Woodward K , Esser M
Published: June 2023

Background: Glasgow Coma Scale (GCS) is the gold standard for neurological assessment in traumatic head injury. Limitations to GCS include variations in rater reliability, test setting and sedation/intubation. Serial Neurological Assessments in Pediatrics (SNAP) was designed to standardize neurological assessment. We examined the efficacy of SNAP for earlier detection of acute neurological decompensation. Methods: Retrospective analysis identified patients with acute neurological decline (drop in GCS of >2 in 1 hour). We reviewed GCS and SNAP (calculated using neurological consultant notes) scores 48 hours prior to decline. Slopes were calculated for each score over time. Results: Four patients were eligible, with > 2 GCS and SNAP scores available for calculation. Average slopes for GCS were 1.3, -0.8, 1.6 and 2.1 for eyes, voice, motor, and total GCS, respectively, and -2.6, 0, -2.3, -2.4, -2.4, -2.0, -2.8 and -11.9 for mental status, cranial nerve, communication, left and right upper extremities, left and right lower extremities, and total SNAP score, respectively. Conclusions: All aspects of the SNAP score had negative and steeper slopes prior to neurological decline, whereas only ‘voice’ in GCS had a negative trend. These findings suggest that the SNAP tool may be useful in earlier identification of acute decline. Ongoing prospective studies are underway.
P.079 A novel case of pickle ball neuropathy
Authors: Gervais CB , Diggle J
Published: June 2023

Background: We report a case of distal right radial cutaneous sensory neuropathy secondary to participation in Pickle Ball. Methods: Case Report & Review of the LiteratureResults: Our 67yoF patient developed acute onset persistent numbness and dysesthesia in the distal right radial sensory distribution while participating in Pickle Ball, a sport undergoing rapid growth of popularity over the past decade. Nerve conduction studies (NCS) were performed in our lab following symptom onset, and the patient had previous NCS that allowed for comparison. NCS in our lab demonstrated asymmetrically reduced amplitude of right distal radial sensory responses (14.5 uV), in comparison to normal (42 uV) radial sensory responses from her previous NCS using the same protocol. All remaining NCS were normal in both studies. Conclusions: This study represents the first reported case within the literature of a Pickle Ball induced distal radial cutaneous sensory neuropathy demonstrated objectively using comparative nerve conduction studies. It is important that clinicians be aware of this entity and the possibility that it can manifest in the context of activities involving repetitive extension of the wrist. We present this case along with a review of the current literature of focal neuropathies involving the upper & lower extremities.
P.084 The Canadian Neuromuscular Disease Registry: a national spinal muscular atrophy registry for real world evidence
Authors: Westbury G , Hodgkinson V , Brais B , Campbell C , Gonorazky H , Lochmüller H , MacKenzie A , McMillan H , Oskoui M , Korngut L , Selby K
Published: June 2023

Background: Patient registries are an effective tool in tracking the natural history of rare diseases as well as post-marketing surveillance of novel therapies. The Canadian Neuromuscular Disease Registry (CNDR) is a pan-neuromuscular disease registry that prospectively collects Spinal Muscular Atrophy (SMA)-specific data in 28 clinics across Canada. The objective of this study is to describe real-world data from the CNDR-SMA patient population. Methods: We report cross-sectional data from Canadian SMA patients. Patients were included in analysis if they were active (alive and with follow-up within 24 months). Results: Of 171 SMA patients included in analyses, 37% currently use non-invasive ventilation, 2% invasive ventilation, and 61% no ventilation support. Feeding tubes are used by 27% of patients. and 28% of patients have a history of scoliosis surgery. Of the 171 patients, 137 have had disease-modifying therapy: 96 on nusinersen, 22 on risdiplam, and 19 on onasemnogene abeparvovec (OA). Median (min,max) years of age at therapy initiation was 7 (0,54), 20.5 (5,53), and 1 (0,6), respectively. At therapy initiation, functional status was 32% non-sitters, 38% sitters, and 30% walkers. Conclusions: The CNDR captures a comprehensive SMA dataset that prospectively evaluates real-world data, supporting post-marketing surveillance of novel therapies in Canada.
P.087 Early and late exercise intervention after lumbar microdiscectomy reduces low back pain, fear avoidance, and improve neurodynamic mobility
Authors: LeBlanc L , Moldovan ID , Ochoa-Sanchez R , Sabri E , Phan P , Agbi C , Mohammed S , AlKherayf F
Published: June 2023

Background: Exercise is commonly recommended to patients following a lumbar microdiscectomy although controversy remains as to the timing and protocols for exercise intervention (early vs late intervention). Our study aimed to evaluate low back pain level, fear avoidance, neurodynamic mobility, and function after early versus later exercise intervention following a unilateral lumbar microdiscectomy. Methods: Forty patients who underwent unilateral lumbar microdiscectomy were randomly allocated to early (Group-1) or later (Group-2) exercise intervention group. The low back pain and fear avoidance were evaluated using Oswestry Low Back Pain Disability Questionnaire, Numeric Pain Rating Scale, and Fear-Avoidance Beliefs Questionnaire. The neurodynamic mobility and function were recorded with Dualer Pro IQ Inclinometer, 50-foot walk test, and Patient-Specific Functional Scale. Measurements were performed before surgery and post-surgery (1-2, 4-6, and 8-10 weeks) after exercise intervention. Results: Both groups showed a significant decrease in low back pain levels and fear avoidance as well as a significant improvement in neurodynamic mobility and function at 4 and 8 weeks post-surgery. No significant difference was detected between the two groups. Conclusions: These findings showed that early exercise intervention after lumbar microdiscectomy is safe and may reduce the low back pain, decrease fear avoidance, and improve neurodynamic mobility and function.
P.089 A literature search using titles and key terms was conducted for articles containing brain death ancillary testing diagnosis, and CTP as primary focus
Authors: Aziz Rizk A , Farhani N , Shankar JJ
Published: June 2023

Background: Ancillary testing assist in the diagnosis of brain death. While traditionally, lack of blood flow (BF) in the intracranial arteries constitutes conclusive evidence that the brain is dead, there is apparent discrepancy between the BF, and sufficient cerebral perfusion; In 15% of patients with confirmed clinical diagnosis of brain death, BF is still preserved. In these patients, cerebral perfusion is significantly impaired suggesting that cerebral perfusion rather than BF more accurately assesses brain function. We aim to present a history of brain death, its pathophysiology, and ancillary tests utilized for its diagnosis- specifically CT Perfusion studies. Methods: A literature search using titles and key terms was conducted for articles containing brain death ancillary testing diagnosis, and CTP as primary focus. Results: Across selected studies, CTP diagnosed brain death with 100% positive predictive value, as none of the patients were proven not-dead on follow-up. The early prediction of mortality outcome in these patients with proven high mortality rate may help decisions for withdrawal of life support. It may also facilitate procurement of organs for transplants. Conclusions: Although clinical assessment is the gold standard method of brain death determination, CTP has shown promising results that could alter our current clinical approach.
P.102 Weighing the risks and benefits of perioperative steroids in the surgical treatment of malignant brain tumours
Authors: James N , Jhawar B
Published: June 2023

Background: Steroids are widely used in medicine because of their anti-inflammatory and immunosuppressive properties; however, they have numerous adverse effects. In neuro-oncology, dexamethasone is the first-line treatment for vasogenic edema caused by malignant brain tumours. This retrospective chart review investigated the risks and benefits of perioperative steroids in the surgical treatment of malignant brain tumours. Methods: All patients (age ≥ 18 years) who underwent a craniotomy for the treatment of a malignant brain tumour at Windsor Regional Hospital between 2012 and 2020 were assessed for eligibility for this retrospective study. Baseline patient characteristics, cumulative perioperative steroid dose, and postoperative outcomes were recorded from electronic medical records (n = 362). Statistical analysis was performed using SPSS. Results: Patients who received a higher cumulative perioperative steroid dose (≥ 80 mg) had a significantly higher rate of postoperative complications compared to those who received a lower dose. These included wound dehiscence, postoperative brain edema on imaging, unplanned return to the operating room, and readmission within 30 days. Conclusions: Steroids are important medications in neuro-oncology, but they are not without potential complications. The findings of this study highlight the need for careful consideration when using steroids in patients undergoing surgical treatment of a malignant brain tumour.
P.104 Grade 3 meningioma survival, recurrence and functional outcomes in an international multicenter cohort
Authors: Rebchuk AD , Tosefsky K , Wang JZ , Ellenbogen Y , Drexler R , Ricklefs FL , Sauvigny T , Schüller U , Cutler C , Lucke-Wold B , Mehkri Y , Lama S , Sutherland G , Karsy M , Hoh BL , Westphal M , Zadeh G , Yip S , Makarenko S
Published: June 2023

Background: Meningiomas are the most common intracranial tumor, graded from 1 (benign) to 3 (malignant). The aim of this study was to identify clinical features associated with overall survival (OS), progression-free survival (PFS) and functional status for malignant meningiomas. Methods: Demographic, clinical and histopathological data from grade 3 intracranial meningioma cases were identified in the clinical databases from seven sites in North America and Europe from 1991-2022. Summary statistics and Kaplan-Meier OS and PFS curves were generated. Results: We identified 108 patients, with a median age 65 years (IQR: 52, 72) and 53.7% were female. Median OS was 109 months (95% CIs: 88, 227), and 5-year OS rate was 65% (95% CIs: 56, 76). Median PFS was 38 months (95% CIs: 24, 56) and 5-year PFS rate was 37% (95% CIs: 28, 49). OS and PFS were significantly lower in patients aged ≥65 years. Median preoperative KPS score was 80 (IQR: 70, 90), postoperatively KPS was 90 (IQR: 70, 98) and 1-year follow-up KPS was 70 (IQR: 50, 80). Conclusions: This study provides robust survival, recurrence and functional data for grade 3 meningiomas in North America and Europe over a 30-year period.
P.121 Memantine inhibits cortical spreading depolarization and improves neurovascular function following traumatic brain injury: results of a randomized pre-clinical trial
Authors: MacLean MA , Muradov JH , Greene R , Van Hameren G , Clarke DB , Friedman A
Published: June 2023

Background: Cortical spreading depolarization (CSD) is associated with poor outcomes following traumatic brain injury (TBI). Here we aimed to: (1) determine the effect of NMDA-receptor antagonism on CSDs in healthy and TBI animals in vivo; and (2) conduct a randomized pre-clinical trial (RCT) of memantine for prevention neurological decline following repetitive mild TBI (rmTBI). Methods: Rodents received either one moderate (n = 23) or four daily mild (rmTBI; n = 30) head impacts (weight drop). Sham animals received brief anesthetic without TBI (n = 40). 93 animals underwent cranial window surgery with electrocorticographic (ECoG) monitoring and electrically triggered CSDs. Ketamine (100uM topical or 25 mg/kg IP) and memantine (10 mg/kg IP) were tested in vivo. An RCT was conducted (N=31) using memantine (10 mg/kg) or saline (2.5 cc/kg) for rmTBI with daily neurobehavioural testing. Results: In TBI animals, ketamine or memantine inhibited CSDs in 44-88%, and 50-67% of cases, respectively. Near-DC/AC-ECoG amplitude was reduced by 44-75% and 52-67%, and duration by 39-87% and 61-78%, respectively. RCT animals that received memantine had higher mean neurological scores (9.27 (SD 3.08) vs. 5.56 (SD 3.05), p< 0.001) vs. saline. Conclusions: Memantine suppressed CSDs following TBI, in vivo. In a pre-clinical RCT of rmTBI, memantine prevented neurological decline.
P.122 Chronic subdural hematoma drainage under local vs. general anesthesia: systematic review and meta-analysis
Authors: Liu E , Zhou A , Tilbury N , Radic J
Published: June 2023

Background: Chronic subdural hematoma (CSDH) is one of the most encountered conditions seen in neurosurgery. Although mainstay treatment of cSDH has been burr hole drainage, no consensus yet exists on optimal anesthesic technique for surgical treatment between general (GA) and local (LA) anesthesia. Methods: A search was conducted in MEDLINE (1946 to November 11, 2022), Embase (1974 to November 11, 2022), and PubMed (up to November 11, 2022). We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to systematically screen studies. Results: Our literature search identified 521 studies, out of which 20 were included. There were a total of 1750 patients who underwent CSDH drainage under LA. The weighted mean age was 71.0 years, and 27.1% were female. Postoperative complication rate was significantly lower in the LA group (odds ratio 0.44, p = 0.004). The mean operative time (mean difference -29.28 minutes, p <0.0001) and length of admission (mean difference -1.58 days, p = 0.0002) were significantly shorter in the LA group. Conclusions: In this meta-analysis, LA shows benefits in shorter operative time, shorter admission length, and fewer postoperative complications. This makes local anesthesia a less invasive alternative to general anesthesia especially in elderly patients.