bluuebunny/crossref_metadata_2025 huggingface dataset:
Vocal Music Recognition Based on Deep Convolution Neural Network
Authors: He Zhuo
Published: February 2022

In order to achieve fast and accurate music technique recognition and enhancement for vocal music teaching, the paper proposed a music recognition method based on a combination of migration learning and CNN (convolutional neural network). Firstly, the most standard timbre vocal music is preprocessed by panning, flipping, rotating, and scaling and then manually classified by vocal technique features such as breathing method, articulation method, pronunciation method, and pitch region training. Then, based on the migration learning method, the weight parameters obtained from the convolutional model trained on the sound dataset CNN are migrated to the sound recognition, and the convolutional and pooling layers of the convolutional model are used as feature extraction layers, while the top layer is redesigned as a global average pooling layer and a Softmax output layer, and some of the convolutional layers are frozen during training. The experimental results show that the average test accuracy of the model is 86%, the training time is about 1/2 of the original model, and the model size is only 74.2 M. The F1 values of the model are 0.88, 0.80, 0.83, and 0.85 in four aspects, such as breathing method, exhaling method, articulation method, and phonetic region training, etc. The experimental results show that the method is efficient for voice and vocal music teaching recognition. The experimental results show that the method is efficient, effective, and transferable for voice and vocal music teaching research.
Experimental Investigation on Mechanical Behaviour of Kevlar and Ramie Fibre Reinforced Epoxy Composites
Authors: Vedanarayanan V. , Kumar B. S. Praveen , Karuna M. S. , Jayanthi A. , Kumar K. V. Pradeep , Radha A. , Ramkumar G. , Christopher David
Published: February 2022

Natural fibre composites have been replacing synthetic fibre composites in practical applications for the last several years because of the features such as low densities, low weight, relatively inexpensive, recyclability, and excellent mechanical qualities unique to the substance. Thus, the current study examines how Kevlar/Ramie/Nano SiC hybrid fibre reinforced composites are made and their mechanical properties, and it compares them to those made using a single natural fibre reinforced composite. It was found that natural fibre composite densities and hardness were all within acceptable ranges by performing composites’ tensile and flexural strength tests. The hand‐lay‐up technique used ASTM standards samples to construct the composite specimens with various fibre weight percentages. Increase in mechanical characteristics was achieved by adding the glass and the epoxy fibres into the epoxy matrix. The hybrid composite’s performance is promising, especially those of individual fibre‐reinforced composites.
Phenotypic Alterations in Cortical Organization and Connectivity across Different Time Scales
Authors: Englund Mackenzie , Krubitzer Leah
Published: February 2022

In the following review, we describe the types of phenotypic changes to the neocortex that occur over the longer time scale of evolution, and over the shorter time scale of an individual lifetime. To understand how phenotypic variability emerges in the neocortex, it is important to consider the cortex as part of an integrated system of the brain, the body, the environment in which the brain and body develops and evolves, and the affordances available within a particular environmental context; changes in any part of this brain/body/environment network impact the neocortex. We provide data from comparative studies on a wide variety of mammals that demonstrate that body morphology, the sensory epithelium, and the use of a particular morphological structure have a profound impact on neocortical organization and connections. We then discuss the genetic and epigenetic factors that contribute to the development of the neocortex, as well as the role of spontaneous and sensory driven activity in constructing a nervous system. Although the evolution of the neocortex cannot be studied directly, studies in which developmental processes are experimentally manipulated provide important insights into how phenotypic transformations could occur over the course of evolution and demonstrate that relatively small alterations to the body and/or the environment in which an individual develops can manifest as large changes to the neocortex. Finally, we discuss how these phenotypic alterations to the neocortex impact an important target of selection – behavior.
Optogenetic Control of Human Induced Pluripotent Stem Cell‐Derived Cardiac Tissue Models
Authors: Gruber Amit , Edri Oded , Glatstein Shany , Goldfracht Idit , Huber Irit , Arbel Gil , Gepstein Amira , Chorna Snizhanna , Gepstein Lior
Published: February 2022

Background

Optogenetics, using light‐sensitive proteins, emerged as a unique experimental paradigm to modulate cardiac excitability. We aimed to develop high‐resolution optogenetic approaches to modulate electrical activity in 2‐ and 3‐dimensional cardiac tissue models derived from human induced pluripotent stem cell (hiPSC)‐derived cardiomyocytes.

Methods and Results

To establish light‐controllable cardiac tissue models, opsin‐carrying HEK293 cells, expressing the light‐sensitive cationic‐channel CoChR, were mixed with hiPSC‐cardiomyocytes to generate 2‐dimensional hiPSC‐derived cardiac cell‐sheets or 3‐dimensional engineered heart tissues. Complex illumination patterns were designed with a high‐resolution digital micro‐mirror device. Optical mapping and force measurements were used to evaluate the tissues' electromechanical properties. The ability to optogenetically pace and shape the tissue's conduction properties was demonstrated by using single or multiple illumination stimulation sites, complex illumination patterns, or diffuse illumination. This allowed to establish in vitro models for optogenetic‐based cardiac resynchronization therapy, where the electrical activation could be synchronized (hiPSC‐derived cardiac cell‐sheets and engineered heart tissue models) and contractile properties improved (engineered heart tissues). Next, reentrant activity (rotors) was induced in the hiPSC‐derived cardiac cell‐sheets and engineered heart tissue models through optogenetics programmed‐ or cross‐field stimulations. Diffuse illumination protocols were then used to terminate arrhythmias, demonstrating the potential to study optogenetics cardioversion mechanisms and to identify optimal illumination parameters for arrhythmia termination.

Conclusions

By combining optogenetics and hiPSC technologies, light‐controllable human cardiac tissue models could be established, in which tissue excitability can be modulated in a functional, reversible, and localized manner. This approach may bring a unique value for physiological/pathophysiological studies, for disease modeling, and for developing optogenetic‐based cardiac pacing, resynchronization, and defibrillation approaches.
Abstract 104: A Step In The Wrong Direction: The Lack Of Drug Subsidies Drives Patients To Switch From Direct Oral Anticoagulants To Warfarin
Authors: Roeder Hannah , Leira Enrique C. C , Shaban Amir , Garg Aayushi , Ghannam Malik , Maljaars Jason , Samaniego Edgar A , Vaughan Sarrazin Mary S
Published: February 2022

Background:
Direct oral anticoagulants (DOACs) are superior to warfarin in preventing ischemic stroke from nonvalvular atrial fibrillation (AF). Transitioning from a DOAC to warfarin is rarely medically indicated. The frequency and determinants of switching from DOAC to warfarin, including the potential influence of cost, are not known.

Objective:
Examine the impact of financial assistance available through Medicaid prescription coverage or low-income subsidy programs on likelihood of switching to warfarin after initiating a DOAC.

Methods:
We identified patients in the Medicare 5% sample who initiated a DOAC from 2015 to 2017. Patients were eligible if they were age 65 or older, had AF diagnosis, had no oral anticoagulant use during the prior 12 months, and were enrolled in a Medicare Prescription Plan for at least 12 months prior to first oral anticoagulant. Patients who switched to warfarin after an initial DOAC were identified, and their characteristics were evaluated in bivariable and multivariable analyses using Cox regression to adjust for potential confounders and censor for death or end of the observation period.

Results:
Of 27,151 eligible patients,16,599 (61%), 8,930 (33%), and 1,622 (6%) initiated apixaban, rivaroxaban, and dabigatran, respectively. 30% (8,110) initiated a low dose DOAC. A total of 1,481 (5.5%) switched to warfarin sometime during the follow-up period. The median time to first warfarin dose among patients who switched was 153 days. Overall, 14% of patients were eligible for Medicaid prescription coverage and an additional 8.8% were eligible for other drug subsidies; these patients were significantly less likely to switch to warfarin, compared to other patients (3.4%, 4.1%, 5.8% of patients with Medicaid coverage, other drug subsidies, or neither). After risk adjustment, the relative hazard of switching to warfarin was 0.57 (95% confidence interval (CI): 0.47-0.68) and 0.69 (95% CI: 0.56-0.85), for patients with Medicaid coverage or drug subsidy, respectively, compared to other patients.

Conclusions:
The financial burden of DOACs may contribute to patients switching to warfarin, despite guideline recommendations. Financial assistance may facilitate evidenced-based best practices in stroke prevention.
Abstract 114: Spoke-administered Thrombolysis Improves Large Vessel Occlusion Early Reperfusion And Inter-hospital Transfer Time For Mechanical Thrombectomy In A Hub-and-spoke Telestroke Network.
Authors: Kraft Andrew , Regenhardt Robert W , Awad Amine , Rosenthal Joseph , Dmytriw Adam A , Vranic Justin , Bonkhoff Anna , Bretzner Martin , Hirsch Joshua , Rabinov James , Stapleton Christopher , Schwamm Lee H , Rost Natalia S , Leslie-mazwi Thabele M , Patel Aman B
Published: February 2022

Introduction:
The utility of intravenous thrombolysis (IVT) prior to mechanical thrombectomy (MT) for large vessel occlusion (LVO) stroke is controversial. Low early recanalization (ER) rates and potential delays to MT may support bypassing IVT before MT. Recent trials suggest MT alone is reasonable for LVO patients presenting directly to MT-capable centers. However, bypassing IVT has not been evaluated for patients first presenting to “spoke” hospitals capable of administering IVT but requiring transfer to a “hub” hospital for MT. Here we examined how spoke IVT influences LVO ER and spoke-to-hub transfer time (TT) within our hub-and-spoke network.

Methods:
Patients presenting to 25 spoke hospitals before hub transfer from 2018 to 2020 who were considered possible EVT candidates with pre-transfer CTA-defined LVO and ASPECTS ≥6 were identified from a prospectively maintained database. ER was determined by chart review of vessel imaging on hub arrival. TT was prospectively recorded. Statistics were performed using permutation resampling and linear regression in R.

Results:
Of 177 patients included, 76 received IVT. Baseline characteristics, NIHSS, and intracerebral hemorrhage were similar between groups. Spoke IVT improved ER frequency [12/76 (15.8%) vs. 3/101 (3.0%), P<0.0001]. Further, spoke IVT was associated with improved ER (aOR=5.9, 95% CI=1.3,33.7, p=0.02), independent of last known well. Patients receiving IVT had decreased mean TT by 25 minutes (139±59 min vs. 164±71 min, p=0.01). Patients with ER had NIHSS interval improvement from spoke to hub [median -2 (IQR 0.0, -3.5) vs. 0 (1.0, -0.4), p=0.02]. IVT was associated with improved 90d mRS ≤2 independent of age, NIHSS, and MT treatment (OR=2.5, 95% CI=1.1, 6.1, p=0.04).

Conclusion:
Within our network, IVT significantly increases ER and decreases TT, which may contribute to improved 90-day outcomes. This retrospective study supports following current recommendations that IVT be given to all eligible patients at spoke hospitals prior to transfer for MT consideration.
Abstract 115: Predictors Of Post-stroke Depression And Suicidal Ideation Among Acute Stroke Survivors
Authors: Aggarwal Seema , Selvaraj Sudhakar , Sharrief Anjail Z , Savitz Sean I , Beauchamp Jennifer E
Published: February 2022

Introduction:
Approximately a third of stroke survivors are diagnosed with Post-Stroke Depression (PSD) and half are more likely to commit suicide compared to the general population. The aim of this study was to examine the relationship between demographic and clinical variables and PSD and suicidal ideation among post-stroke survivors.

Methods:
This was a retrospective review of a clinical registry from a comprehensive stroke center between 10/2018 and 3/2020. Patients were eligible if a Patient Health Questionnaire 9-Item (PHQ-9) was available. Question 9 of the PHQ-9 was screened for suicidal ideation.

Results:
The study cohort consisted of a total of 194 patients who had an acute (primarily ischemic or intracerebral) stroke who completed a 90-day telephonic PHQ-9. The mean age (years) and NIH Stroke Scale were 64 ± 15 and 7.4 ± 7.3, respectively. The sample was comprised of 56% men, 39% Whites, 31% Blacks, 27% Asians, and 10% Hispanics. The mean PHQ-9 score was 5.9 ± 6.3. Seven percent reported suicidal ideation. Univariate analysis revealed that pre-stroke depression history and 90-day post-dicharge mRS scores were significantly associated with PHQ-9 scores (p=0.005 and p=0.003, respectively). After adjusting for age, stroke type, NIHSS arrival score, pre-morbid mRS score, mRS score at 7 days, and hospital length of stay, multiple linear regression analysis with bootstrap estimates found that pre-stroke depression and 90-day post-dicharge mRS scores remained significant (p<0.001 and p=.004, respectively; see Table 1). Although both days 7 (p=0.014) and 90 (p=0.049) mRS scores were found to be significantly different than those with and without suicidal ideation, the effect size in patients with suicidal ideation was larger for day 90 (d=.66) than for day 7 (d=.36) mRS scores.

Conclusion:
Patients with a history of depression and those with higher mRS scores at 90 days should be screened for suicidal ideation and actively managed for depression.
Abstract 120: Using CT Perfusion To Measure Territory Volumes In Intracranial Atherosclerosis
Authors: Pavlin-Premrl Davor , Christensen Soren , Boopathy Sethu , Nemes Andras , Thijs Vincent , Parsons Mark , Yassi Nawaf , Mitchell Peter J , churilov leonid , Yeo Leonard , Mohammadzadeh Milad , Monajemi Sadaf , Campbell Bruce
Published: February 2022

Introduction:
Intra- and inter-individual variation in cerebral artery territory volumes is likely due to haemodynamic factors mediated by collaterals. We investigated the association of intracranial atherosclerosis (ICAD) with changes in vascular territory volumes as a potential marker of collateral function.

Methods:
Patients with symptomatic ICAD (50-99% stenosis) and controls were identified. Territories were mapped using a published CT Perfusion (CTP) post-processing technique where seed points for the MCA, ACA and PCA territories are manually chosen, and the arrival of contrast bolus is tracked until it arrives at the boundaries of adjacent territories. In ICAD patients, the ratio of the intracranial atherosclerosis-affected territory volume to its contralateral counterpart, and ratios of the adjacent territory volumes to their contralateral counterparts, were calculated. Ratios of paired arteries were calculated in the control group. Using the Mann-Whitney U test, territory ratios in ICAD patients were compared to control patients.

Results:
In 30 patients (15 cases, 15 controls), the ICAD-affected territory ratios (median = 0.79, IQR 0.46 - 0.93) were significantly smaller than the control ratios (median = 0.98, range IQR 0.87 - 1.12), p = 0.004. The adjacent territory ratios (median = 1.30, IQR 1.07 - 1.65) were significantly larger than control ratios, p<0.00001.

Conclusion:
This study suggests that routinely-obtained CTP-derived vascular territory maps can quantify territory volume derangement in intracranial atherosclerosis. Our findings are consistent with the hypothesis that collateral recruitment from adjacent territories maintains perfusion in ICAD-affected territories. Notably, the range of values seen in ICAD patients was wide, possibly reflecting different collateralisation patterns. This technique may be useful as an objective measure of collaterals in ICAD and to better understand hemodynamics in individual patients.
Abstract 122: Untargeted Proteomics And Carotid Artery Atherosclerosis: The Cardiovascular Health Study
Authors: Kalani Rizwan , Bartz Traci , Psaty Bruce , Delaney Joseph , Elkind Mitchell , Tirschwell David L , Longstreth W T
Published: February 2022

Background:
Increased carotid intima-media thickness (cIMT) and moderate-severe carotid artery atherosclerosis (CAA≥50%) are associated with increased risk of stroke. We evaluated proteomic determinants of increased cIMT and CAA≥50% in the population-based Cardiovascular Health Study (CHS).

Methods:
Eligible participants underwent carotid artery ultrasound and aptamer-based SOMAScan platform measurement of 1298 serum proteins from the concurrent study visit. cIMT was defined as the average of the standardized values of the maximal common carotid artery IMT and maximal internal carotid artery IMT. CAA≥50% was defined as carotid plaque resulting in ≥50% luminal stenosis. The relationship between each log-normalized protein concentration with cIMT and CAA≥50% was modeled separately using multivariable linear regression and logistic regression, respectively, adjusting for demographics, estimated glomerular filtration rate (eGFR), and CAA risk factors. Bonferroni correction, based on the number of principal components that explained 95% of the protein concentration variance in CHS participants, was employed to account for multiple hypothesis testing, yielding a
p
-value for significance of <7.6x10
-5
(0.05/661).

Results:
For eligible participants (n=2783), mean age was 74.4 ± 4.9 years, 39.5% were men, and 15.8% were Black. After adjustment for demographics, eGFR, and CAA risk factors, 13 proteins were independently associated with increased cIMT (Table). The magnitude and direction of the associations were similar in subgroups defined by sex and race. Three proteins were associated with CAA≥50%, after adjusting for eGFR and demographics (Table); however, associations were no longer significant after adjusting for CAA risk factors.

Conclusion:
Multiple novel serum proteins - implicated in extracellular matrix remodeling, systemic inflammation, and coagulation - were independently associated with increased cIMT in a cohort of older adults.
Abstract 133: Resolute Stents Less Likely Than Wingspan To Have Periprocedural Complications With A Significant Improvement In Long Term Restenosis Rates
Authors: Hassan Ameer , Khalil Mohammad , Desai Sohum , Tekle Wondwossen
Published: February 2022

Background and Purpose:
Angioplasty and stenting is a treatment option for patients with medically refractory symptomatic intracranial atherosclerotic disease (sICAD). Currently the Wingspan Stent System (WSS) is the only FDA approved device for that indication. Nonetheless, our group has shown the Resolute (R) Onyx Stent, a drug-eluting balloon mounted stent (DES), can be feasibly used to treat lesions in this population at lower cost. Herein, we compare the two stents based on our single center experience.

Methods:
A prospectively maintained neuro-endovascular databased was queried for patients between January 2013 to June 2021. Inclusion criteria for patients included sICAD (≥70% stenosis) with failed medical management, and intracranial stenting with either the R-onyx DES or WSS, including patients treated within 7 days of last stroke. Primary outcomes were assessed via the occurrence of ischemic or hemorrhagic stroke or death within 72 h of the procedure while secondary outcomes consisted of stroke or angiographic reoccurrence (in-stent restenosis) evaluated by a clinical or angiographic follow-up at 6 months.

Results:
A total of 184 patients, average age 61.26 (SD=12.53) ( 44% women), were eligible for analysis with 58 having R-onyx DES and 126 having WSS. There was no significant difference in age or premorbid risk factors between the two groups. Within 72 h, 1.7% (n=1) of patients had a primary event of ischemic or hemorrhagic stroke or death in the R-onyx DES group while 6.3% (n=8) of patients had those indications in the WSS group (p = 0.089). Among 41 angiographic and clinical follow-ups in the R-onyx DES group, none had a stroke, while among 101 of those follow-ups in the WSS group, 8.9% (n=9) had a stroke (p=0.024). In terms of 6-month angiographic follow-ups, there was a significantly lower rate of symptomatic in-stent restenosis among the R-onyx DES group with 1.7% (n=1) experiencing symptomatic in-stent restenosis, and 21.4% (n=27) in the WSS group having that indication (p=0.0003).

Conclusion:
Our experience has been that R-onyx DES is more effective at treating sICAD with low rates of periprocedural complications within 72 h, long-term strokes, and symptomatic in-stent restenosis. Future prospective randomized multicenter trials are needed.
Abstract 143: Stroke-Associated Metabolites And Dietary Patterns In The Reasons For Geographic And Racial Differences In Stroke (REGARDS) Cohort
Authors: Bhave Varun , Ament Zsuzsanna , Chaudhary Ninad , Patki Amit , Garcia Guarniz Ana-Lucia , Cushman Mary , Judd Suzanne , Irvin Marguerite , Kimberly W Taylor
Published: February 2022

Introduction:
Several diet patterns have previously been associated with incident stroke risk in the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. We used metabolomics to assess biological state changes that could link diet exposures to stroke risk.

Hypothesis:
Metabolites linked to stroke risk are correlated with adherence to unhealthy and protective dietary patterns.

Methods:
Using liquid chromatography-tandem mass spectrometry, we analyzed 162 metabolites in baseline plasma samples from REGARDS subjects with or without incident stroke (n = 2,249). Survey-weighted Cox models adjusted for age, race, and sex identified metabolites associated with incident ischemic stroke. Candidate metabolites were correlated with diet patterns using linear regression.

Results:
Correlations between stroke-associated metabolites and diet patterns linked to higher (Southern diet) or lower (Mediterranean and plant-based diets) stroke risk were consistent with known effects on stroke risk conferred by each metabolite and diet pattern. Notably, the “harmful” nucleoside guanosine was positively correlated with Southern diet (β = 0.11, FDR = 4.7x10
-3
) and negatively with Mediterranean (β = -0.11, FDR = 3.2x10
-2
) and plant-based diets (β = -0.13, FDR = 1.6x10
-4
). In contrast, the “protective” indole-3-propanoic acid, derived from tryptophan metabolism by gut microbiota, was negatively correlated with Southern diet (β = -0.23, FDR = 3.0x10
-6
) but positively with Mediterranean (β = 0.15, FDR = 6.1x10
-3
) and plant-based diets (β = 0.23, FDR = 1.5x10
-5
). Inverse odds ratio weighting mediation analyses showed that guanosine levels partly mediated the protective effect of a plant-based diet (indirect effect hazard ratio [HR] = 0.94, 95% CI = 0.86-0.99) and Mediterranean diet (indirect effect HR = 0.94, 95% CI = 0.85-0.99) on stroke risk. We also examined associations between stroke-linked metabolites and 265 specific food items, finding that unhealthy intakes were positively correlated with harmful metabolites and vice versa.

Conclusion:
Metabolites relevant to ischemic stroke risk correlate with broader diet patterns and specific food exposures. Metabolome perturbations might link dietary intake and the gut microbiota to stroke risk.
Abstract 145: Trends In The Incidence Of Spontaneous Subarachnoid Hemorrhages In The United States From 2006 To 2017
Authors: Xia Christina , Philip Karan , Anikpezie Nnabuchi , Albright Karen C , Latorre Julius Gene S , Otite Fadar O
Published: February 2022

Introduction:
Global incidence of subarachnoid hemorrhage (SAH) is reportedly decreasing, but recent studies from the United States (US) are limited. The goal of this study is to evaluate trends in the incidence of SAH in different age, sex, and ethnic subgroups in the US over the last decade.

Methods:
We identified all new cases of spontaneous SAH from the 2006-2017 State Inpatient Databases in New York and Florida (n = 45,703) using validated International Classification of Diseases codes. Annual incidence was calculated by combining case counts with annual Census data. Joinpoint regression was used to trend incidence over time.

Results:
From 2006-2017, the mean age of SAH patients was 61.8 years and 59.3% were women. The proportion of smokers was 27.2% and this significantly increased over time (p<0.001). The annual age and sex-standardized incidence of SAH in cases per 100,000 ranged from 11.4-13.7, but women had a higher overall incidence (13.4-15.2) compared to men (9.2-12.1). When stratified by age groups, women(W) had a higher incidence of SAH compared to men (M) in similar age groups (age 20-44: W 4.7-5.7, M 3.3-4.4; age 45-64: W 16.2-18.2, M 11.0-14.7; age >=65: W 26.8-33.2, M 20.9-31.2). On Joinpoint regression, M >=65 yo had the highest annualized percentage change in incidence of 3.1% (95% CI 2.0-4.3). M 45-64 yo had an increase of 1.7% (95% CI 0.9-2.5) and W >=65 yo had an increase of 1.3% (95% CI 0.4-2.2). Incidence declined in W 20-44 yo by -1.0% per year while M 20-44 yo remained unchanged (Figure 1). On stratification by race, age and sex-standardized incidence was highest among African Americans (14.6-18.6 per 100,000), followed by Whites (10.0-11.9), Latino (8.0-11.3), and Asians (6.6-9.9).

Conclusion:
When compared to European studies, US residents have a higher incidence of spontaneous subarachnoid hemorrhage. The incidence of SAH is increasing in the older population and is highest among women and African Americans.
Abstract 17: Microglial Specific Aryl Hydrocarbon Receptor Activation Via Gut-derived Microbial Indole-metabolites Improves Outcomes After Neonatal-HIE
Authors: Korf Janelle , St Denis Anna , Honarpisheh Pedram , Banerjee Anik , Mohan Eric , Blixt Frank , Sharmeen Romana , Lee Juneyoung , Blasco-Conesa Maria P , McCullough Louise , Ganesh Bhanu P
Published: February 2022

Introduction:
Neonatal Hypoxic Ischemic Encephalopathy (nHIE) is a major cause of mortality and morbidity in infants, occurring in 1.5/1000 live births. Inflammation persists years after injury and detrimentally affects neurocognitive outcomes in children. Recent evidence shows that neuroinflammation and gut injury alters microbial populations in the gut (gut dysbiosis) and reduces the level of bacteria capable of producing beneficial, anti-inflammatory tryptophan (Trp) metabolites. Metabolites are detected by microglia (MG) with the aryl hydrocarbon receptor (AHR). Ligand specific AHR activation can influence MG behavior after CNS injury, potentially modifying recovery.
We hypothesize
that nHIE leads to chronic gut dysbiosis and reduced microbial-derived Trp metabolites, which exacerbates MG-induced CNS damage. We also hypothesize that Trp-derivatives bind MG AHR to reduce inflammation and improve neurological outcomes in males and females.

Methods:
We used a modified Rice Vannucci Model on PND9 C57BL/6J mice to investigate the role of MG AHR as a mediator of gut microbiome-brain communication after nHIE and demonstrated direct microbial metabolite modulation of MG using
in vitro
cell culture assays.

Results:
We found an increase in AHR and CD45 expression in MG 24hrs after nHIE (p=0.0169 and p=0.0047 respectively, n=5). RT-qPCR of SIM-A9 MG cells showed that pretreatment with indole-acetic-acid (IAA) followed by LPS injury produced significantly more
Il10
than cells pretreated with AHR agonist FICZ, suggesting Trp-derivatives activate an anti-inflammatory response (p=0.013, n=8). IAA mildly reduced
Il1β
,
Il6
, and
Tnfα
after LPS administration. 16S rRNA sequencing, behavior and metabolomics analysis of acute (24hrs) and chronic (7wks) cohorts showed detriments in behavioral tasks and dysbiotic changes after nHIE.

Conclusion:
nHIE results in increased AHR expression in MG, gut dysbiosis, and alterations in microbial-Trp metabolites in males and females.
In vitro
assays demonstrated that absence of Trp metabolites result in greater inflammatory activity of MG after injury via the AHR pathway, supporting our hypothesis that reduction of microbial-derived Trp metabolites after nHIE worsens MG-induced CNS damage.
Abstract 2: African American Patients Without Pre-existing Cognitive Impairment Are More Likely To Develop Post Stroke Cognitive Impairment After First-ever Stroke: An Analysis Of Electronic Health Record Data
Authors: Zha Alicia , Zhang Chenguang , Anjum Sahar , Dai Jianliang , Savitz Sean I , Wu Hulin
Published: February 2022

Background:
Post stroke cognitive impairment (PSCI) can be as high as 15-70% after stroke depending on the patient population and diagnostic tool. Few studies on PSCI have utilized large administrative or electronic health records (EHR) to evaluate trends in PSCI in the current population.

Methods:
We analyzed Cerner Health Facts® EMR database, which is comprised of de-identified EHR data from over 700 hospitals and clinics in the US from 2000-2018. We evaluated patients ≥40 years of age with a first time acute ischemic stroke (AIS) diagnosis using ICD9/10 codes. PSCI was defined as pts with ICD 9/10 codes for dementia, mild cognitive impairment, or on medications for dementia. Pts with first stroke in the Cerner database and no pre-existing cognitive impairment were included; those with no follow-up visits in the system were excluded. We compared hazard ratios for developing PSCI for patient characteristics.

Results:
A total of 211,622 AIS pts were evaluated, of which 153,078 had follow-up data in the system and no prior diagnosis of PSCI. Among these, the rate of PSCI was 9.29%. Most pts qualified under PSCI using dementia ICD codes (15,280) compared to mild cognitive impairment codes (4,321) or medication usage (1,032). Median time to PSCI diagnosis was at their first follow-up visit within the first year after stroke. Pts ≥65 years of age at time of stroke (HR 2.95, 95% CI 2.83,3.07) and of African American race (HR 1.37, 95% CI 1.31,1.46) were more likely to develop dementia. There were no disparities for developing PSCI between Hispanic and non-Hispanic pts (HR 0.89, 95% CI 0.69, 1.16). Male pts were less likely to develop PSCI than female counterparts (HR 0.84, 95% CI 0.81,0.87).

Conclusion:
Our analyses highlight the viability of utilizing large administrative databases to assess trends in PSCI diagnosis. The number of pts with PSCI may be underestimated however, given the importance of EHR records in patient care, this suggests PSCI is under-diagnosed in the community. Previously described racial disparities for black survivors persisted but male patients had less PSCI. Further study into other administrative databases is necessary to assess if these data are consistent in other EHR systems and to evaluate new trends in PSCI diagnosis and treatment.
Abstract 22: Geospatial Modeling To Optimize Mobile Stroke Unit System Deployment In A Large Metropolitan Region
Authors: Nour May , Vassar Stefanie D , Brown Arleen F , Bosson Nichole E , Chidester Cathy , Liebeskind David S , Kazan Clayton , Sanko Stephen , Eckstein Marc , Gausche-Hill Marianne , Saver Jeffrey L
Published: February 2022

Introduction:
Transition from evidence to practice is the next challenge for Mobile Stroke Units (MSUs) now that two controlled studies have shown improved outcomes (BEST-MSU and B_PROUD). This requires successful integration into EMS systems. We sought to utilize geospatial mapping to identify the most efficient number and positioning of MSUs in Los Angeles (LA) County to maximize patient access.

Methods:
LA County has one of the largest EMS systems in the US, comprising 88 cities, more than 4000 sq miles, and a population of 10.2 million. Using ESRI/ArcGIS software, we performed geospatial mapping of all 911 calls resulting in a final diagnosis stroke from July 2016 - June 2019, converting street addresses to latitude/longitude. Regional heatmaps of stroke call volume were generated for day/evening (7 am-10 pm) vs nighttime (10 pm-7 am) and ischemic vs hemorrhagic stroke, superimposed upon available stroke centers and neighborhood sociodemographic factors. Based on pilot experience, each MSU was projected to be able to service a 10-mile radius.

Results:
Among 10,818 EMS responses for acute cerebrovascular disease during the 3-year study period, calls occurred during day/evening in 84.5% and nighttime in 15.5%. Stroke type was ischemic in 78.8% and hemorrhagic in 21.2%. Heat maps revealed multifocal geographic hotspots, with most active locations somewhat different for day/evening vs night and ischemic vs hemorrhagic. The spatial analysis algorithm determined that optimal placement of 5 MSUs in highest incidence areas would provide coverage for 87.0% of county stroke events. Positioning of 2 additional units in geographically isolated perimeter areas increased coverage to 91.9% of stroke events (Figure).

Conclusions:
Geospatial modeling can delineate the most efficient positioning of MSU resources within regionalized EMS systems of stroke care. Optimal position varies with time of day and with prioritization of coverage for ischemic vs hemorrhagic stroke.
Abstract 25: Tenecteplase Is Safe And Efficacious In Telestroke Patients With Confirmed Large Vessel Occlusions
Authors: Hackett Chris T , Malhotra Konark , Cerejo Russell , Shurina Christy A , Powell Kayla , Henderson Melanie , Butterfield June , New Christine , Noah Patty , Rana Sandeep , Fishman Robert A , Wright David G , Williamson Richard , Tayal Ashis H
Published: February 2022

Introduction:
Tenecteplase has been demonstrated to be an effective option for thrombolysis in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). Thrombolysis decision making is an important component of telestroke consultations. Data is scarce concerning tenecteplase usage in telestroke patients. We aimed to evaluate if tenecteplase was safe and feasible for patients with confirmed LVO in a large telestroke network.

Methods:
We conducted a retrospective analysis of AIS patients with LVO and treated with thrombolysis from May 2018 to April 2021. We compared outcomes in telestroke patients treated with IV alteplase (May 2018 - April 2020) to patients treated with IV tenecteplase (May 2020 - April 2021). We evaluated our primary efficacy and safety outcomes: 90 day functional outcome as measured by modified Rankin Scale (mRS) and complications related to thrombolysis. Secondary outcomes included door to needle time (DTN) and door in door out time (DIO). Ordinal regression assessed 90 day mRS and binomial logistic regression analysis evaluated complications between the groups. Quantile regression models assessed the median to compared groups for DTN and DIO.

Results:
There were 3747 telestroke consults during the study period and 537 (14.3%) were found to have an LVO, of which 109 (39 IV tenecteplase; 70 IV alteplase) were eligible, received thrombolysis and were included in this study. Patients treated with IV tenecteplase had significantly less disability at 90 days compared to patients treated with IV alteplase [1 (0 - 4.5) vs. 3 (1 - 6)], adjusted odds ratio (aOR) = 0.31 [95%CI, 0.14 - 0.72], p = 0.006, based on mRS ordinal shift analysis. Similar complication rates were reported between the thrombolysis groups, aOR = 3.73 [95%CI, 0.23 - 59.95], p = 0.35. An adjusted quantile regression model found IV tenecteplase was administered 9.40 minutes quicker, standard error (SE) = 3.67, [95%CI, 2.11 - 16.69] than IV alteplase, p = 0.01. There were no differences reported between thrombolysis groups and DIO, p = 0.63.

Conclusion:
Telestroke patients presenting with confirmed LVO and treated with IV tenecteplase were found to have better 90 day outcomes compared to patients treated with IV alteplase, without increased complication rates.
Abstract 3: Higher Pre-stroke Physical Activity Is Associated With Fewer Post-stroke Depressive Symptoms In Patients Treated With Citalopram As Compared To Placebo
Authors: Vestergaard Sigrid Breinholt , Damsbo Andreas Gammelgaard , Blauenfeldt Rolf , Andersen Grethe , Mortensen Janne K
Published: February 2022

Introduction:
Post-stroke depression affects one in three stroke patients and is associated with increased mortality and disability. Physical activity (PA) has been associated with fewer depressive symptoms after stroke, however, the long-term effect of pre-stroke PA and how Selective Serotonin Reuptake Inhibitors may affect this association is unknown.

Methods:
The study was conducted as a secondary analysis of data from The Efficacy of Citalopram Treatment in Acute Ischemic Stroke (TALOS) trial, where consecutive non-depressed acute ischemic stroke patients were randomized to Citalopram 20 mg or placebo for 6 months. Pre-stroke PA was measured using the Physical Activity Scale for the Elderly (PASE) and dichotomized by overall median value. Depressive symptoms were measured using the Major Depression Inventory (MDI) at one and six months after stroke. We used multivariable linear regression models to evaluate the interaction of pre-stroke PASE score and post-stroke MDI score.

Results:
We included 543 patients with complete PASE and MDI data at one month. Of these, 257 (47.3%) were in the SSRI group, 75% were men, and median (interquartile range) age was 69 (60 to 77). Overall, high PASE score was associated with lower MDI scores both one month (mean difference [confidence interval (CI)] -2.02 [-3.28 to -0.75]) and six months (-1.71 [-3.21 to -0.2]) after stroke. At one-month, a high PASE score was associated with lower MDI scores in the placebo group (mean difference -2.14 [-3.74 to -0.54]). After six months, an association between high pre-stroke PASE and lower MDI score was only found in the Citalopram group (mean difference -1.71 [-3.21 to -0.2]). Among patients with high pre-stroke PASE score the Citalopram group had lower MDI scores than the placebo group at six months (mean diff 2.01 [0.25 to 3.77]).

Conclusions:
High pre-stroke PA was independently associated with fewer depressive symptoms one and six months after stroke, however at six months the association was only present among those treated with Citalopram, suggesting an effect modification by Citalopram on the effect of PA on depressive symptoms. Further trials are warranted to verify these results.
Abstract 30: Black On Black: Stroke Outcomes In Foreign Vs. Us Born Individuals Of African Ancestry
Authors: Lekoubou Alain , Ovbiagele Bruce , Markovic Daniela , Towfighi Amytis
Published: February 2022

Introduction:
Black individuals are disproportionally affected by stroke, yet little is known about the effect of region of origin and acculturation on stroke mortality. We examined associations between nativity and stroke outcomes among Black individuals in the US.

Methods:
Using the National Health Interview Service 2000-2014 data and mortality linked files through 2015, we identified participants aged 25-74 years who self-identified as Black (n=64,717). We categorized Black race by birth region, i.e. foreign-born (Caribbean, South and Central American, and African) vs. US-born. Stroke was determined by self-report. Using Cox regression, we examined the association between nativity and all-cause, cardiovascular (CV), and stroke mortality, adjusting for age, sex, education, income, smoking, and body mass index, overall and by time since migration.

Results:
Overall, 4329 deaths (including 205 stroke and 932 CV deaths) were recorded during the study period. Weighted cumulative incidence of all-cause, CV, and stroke mortality at 10 years follow up were 12.62%, 2.76%, and 0.59% for those born in the US; 6.12%, 1.58%, and 0.45% for those born in the Caribbean, South and Central America; and 3.15%, 0.54%, and 0.08% for those born in Africa. In the model adjusted for demographic factors, compared to US-born Black individuals, rates of all cause and CV mortality were lower among Black individuals born in the Caribbean, South and Central America [all-cause mortality: aHR (95%CI): 0.46 (0.38-0.55); CV mortality [0.60 (0.40-0.89)], but rates of stroke mortality were similar [1.00 (0.55-1.99)]. African-born Black individuals had lower all-cause mortality rates [0.50 (0.32-0.80)] and trended toward having lower CV [0.47 (0.20-1.13)] mortality rates compared to those born in the US. The above findings remained similar after adjusting for smoking and BMI. Time since migration did not significantly affect mortality outcomes among foreign born Blacks.

Conclusion:
Foreign-born Black individuals generally have lower all cause and CV mortality regardless of time since migration. These findings highlight the need for more granular information regarding region of origin and acculturation to understand and target racial disparities.
Abstract 34: A Stroke Transition Of Care Intervention With Stroke Nurse Navigator And Early Stroke Clinic Follow-up Reduces Readmissions For Stroke At 12 Months
Authors: Matmati Kelly , Matmati Nabil , Madison Susan , Vogl Susan , Bixler Brian , Vogler Kelsey , Dombovy Mary , Burke Chris
Published: February 2022

Introduction:
Stroke is a leading cause of disability in the United States, and one in four occur in people who have already had a stroke. Preventable hospital readmissions contribute to the high medical costs of stroke. Transition of care programs have been successful in reducing hospital readmissions in other diseases, but the data on such programs for stroke is mixed. A transition of care program was implemented at a large urban stroke center, utilizing interventions shown to be effective in the literature, with the goal of reducing recurrent strokes and hospital readmissions.

Methods:
The transition of care program consisted of: two Stroke Nurse Navigators, personalized stroke education in the hospital, two-day phone call reinforcing education and reviewing medications, early follow-up within 7-10 business days with a Stroke Neurologist, and further education on personalized risk factors in the clinic. Baseline data from the year prior to intervention, and each quarter of the three-year project period were obtained on the following measures: Rate of recurrent stroke admissions within one year, all-cause readmission within one year, all-cause readmission within 30 days, patient scheduled for initial follow-up within 7-10 days, compliance with follow up in the stroke clinic, and percent of patients receiving two-day post discharge phone call. Discharge data were reviewed on 949 patients in 2016 (year 0) and on 2,328 patients in the three-year project period (starting in July 2017).

Results:
The rate of readmission for stroke was 8.5%, 9.0%, 6.6%, and 4.2% for year 0, 1, 2, and 3, respectively. This represents a reduction of 50% from the year prior to the intervention to year 3 of the grant. All-cause readmission remained stable, at 38.9%, 42.6%, 36.6%, and 37.4% for year 0, 1, 2, and 3 respectively. An improvement was seen in process measures: patients scheduled for early follow up in the stroke clinic, adherence to follow-up, and two-day post-discharge phone calls.

Conclusions:
In conclusion, the transition of care intervention led to a reduction from baseline in readmissions for stroke within one year, but did not impact all cause readmission at one year or 30 days. This is a meaningful outcome for those who have suffered strokes. This program can serve as a model.
Abstract 39: Ability Of Radiomics Versus Humans In Predicting First-pass Effect After Endovascular Treatment In The Escape-na1 Trial
Authors: Bala Fouzi , Qiu Wu , Kappelhof Manon , Cimflova Petra , Kim Beom J , McDonough Rosalie , Singh Nishita , Kashani Nima , najm mohamed , Ospel Johanna Maria , Wadhwa Ankur , Nogueira Raul G , McTaggart Ryan A , Demchuk Andrew M , Poppe Alexandre , Almekhlafi Mohammed , Goyal Mayank , Hill Michael , Menon Bijoy K
Published: February 2022

Introduction:
First-pass effect (FPE), i.e., achieving reperfusion with a single thrombectomy device pass, is associated with better clinical outcomes in patients with acute stroke. FPE is therefore increasingly being used as a marker of device and procedural efficacy. We evaluated the ability of thrombus-based radiomics models to predict FPE in patients undergoing endovascular thrombectomy (EVT) and compare performance to experts and non-radiomics thrombus characteristics.

Methods:
Patients with thin-slice non-contrast CT and CT angiography from The Efficacy and Safety of Nerinetide for the Treatment of Acute Ischemic Stroke (ESCAPE-NA1) trial were included. Thrombi were manually segmented on all images. Data was randomly split into a derivation set that included a training and a validation subset and an independent test set. Radiomics features were extracted from the derivation data set. Three expert stroke physicians reviewed baseline imaging and clinical data for the test set. The machine learning (ML) models were compared to the three experts in predicting the primary outcome (FPE) in the test set using area under the receiver operating characteristic curves (AUC-ROC).

Results:
A total of 554 patients with available thin-slice images comprised of a derivation set (training subset [n=388, 70%]), validation subset [n=55, 10%]), and a test set (n=111, 20%). FPE was seen in 31.8% in the derivation set and 31.5 % in the test set. AUC of the best radiomics model was 0.74 (95% CI: 0.64, 0.84), which was higher than the mean AUC of the three experts 0.60 (95% CI: 0.50, 0.71) (
P
=0.009). Specificity of radiomics was better than the mean specificity of the three experts, 46 of 76 (60%) vs. 35 of 76 (46.4%),
P
=0.004, whereas sensitivity was not significantly different between radiomics (28 of 35 [79%]) and experts (27 of 35 [77%]). Moreover, radiomics features performed better than non-radiomics features such as thrombus volume and permeability measurements in predicting FPE (
P
<0.05).

Conclusion:
A radiomics-based ML model of thrombus characteristics on non-contrast CT and CT angiography performs better than experts and non-radiomics image characteristics in predicting FPE in patients with acute stroke treated with EVT.