bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract WMP94: Temporal Trends in Racial, Age, and Sex-Specific Utilization of Decompressive Hemicraniectomy Among Acute Ischemic Stroke Patients in the United States
Authors: Polineni Sai P , Otite Fadar O , Chaturvedi Seemant
Published: June 2021

Background:
The aim of this study is to evaluate current trends in racial, age, and sex-specific utilization of decompressive hemicraniectomy (HC) in acute ischemic stroke (AIS) patients in the United States over the last decade.

Methods:
All adult patients with a diagnosis of AIS were identified from the 2004-2015 Nationwide Inpatient Sample (weighted N=4,792,428) using International Classification of Diseases Ninth revision (ICD-9) codes. Proportion of patients undergoing HC in various age, race, and sex groups were ascertained using ICD-9 procedural codes. Temporal trends were mapped by year in order to track changes in utilization over time. Analysis of utilization disparities and trends within age, sex, and race subgroups was conducted via multivariate logistic regression.

Results:
Of all eligible AIS patients from 2004-2015, 0.25% underwent HC (.08 in 2004 to .46 in 2015). Increased utilization over time was seen in both men (.13 to .57) and women (.08 to .54), with women showing comparable odds of utilization to men [OR: 0.95 (95% CI: .87-1.04, p=0.27)]. Similarly, increased utilization trends were seen in all age groups (Figure 1) with the highest rates in the 18-39 subgroup (1.41%). Compared to trends in this younger subgroup (.43 to 2.12), patients aged 60-79 experienced a similar overall increase but at lower utilization rates (.06 to .37). Compared to white patients in multivariate models, blacks did not show significant differences in odds of HC [1.09 (.96-1.24, p=0.20)], while patients from Hispanic [1.25 (1.03-1.51, p=0.02)] and other [1.26 (1.04-1.52, p=0.02)] race-ethnic groups showed increased odds.

Conclusions:
From 2004-2015, hemicraniectomy rates have seen substantial increases in all age, sex, and race groups. The increasing rates of hemicraniectomies among those over age 60 suggest that there has been at least partial acceptance of DESTINY 2 study results.
Abstract WP1: High-Frequency Optical Coherence Tomography for Cerebrovascular Disease
Authors: Puri Ajit S , Ughi Giovanni , King Robert M , Gounis Matthew
Published: June 2021

Introduction:
Optical coherence tomography (OCT) has played an important role in the diagnosis and treatment guidance in coronary artery disease. However, existing OCT systems are not suitable for routine neurovascular applications due to the size and tortuosity of the arteries.

Hypothesis:
We seek to demonstrate a prototype high-frequency OCT (HF-OCT) capable of high-resolution imaging in simulated cerebrovascular anatomy.

Methods:
A low-profile HF-OCT system was constructed with an image resolution approaching 10μm. Using an in vitro, patient-specific model of the circle of Willis with circulating porcine blood, we characterized the delivery of the device and ability to image in a tortuous path. Also, human cadaver intracranial atherosclerosis plaques were imaged with HF-OCT and assessed by an expert imager. Finally, neurovascular devices were implanted in 8 pigs (Fig 1) and HF-OCT imaging was compared with gold-standard DSA and CT.

Results:
In the phantom, optimal blood clearance was achieved through an intermediate catheter (5 Fr Navien) with infusion of contrast at 5 ml/s in the internal carotid and basilar artery, and 3 ml/sec in the MCA. The in vivo study demonstrated that both malapposition of devices or thrombus formation along the device surface could be reliably diagnosed among 3 reviewers (Fleiss’s kappa of 0.87 and 0.9, respectively). This agreement was superior to DSA and CT. Imaging in tortuous swine brachial showed in all cases imaging free of artifacts, uniform illumination and ability to visualize vessel wall layers. Plaque types including ‘lipid pools’, fibrotic, and calcific tissue from cadaver specimens of ICAD could be adequately depicted by HF-OCT.

Conclusion:
In vitro, in vivo and ex vivo characterization of a novel HF-OCT device has shown it is capable of imaging in the tortuous intracranial vascular anatomy. This technology has to potential to aid in the diagnosis of cerebrovascular disease and guide optimal endovascular treatment.
Abstract WP108: Novel Human Acute Ischemic Stroke Blood Clot Analogues for
in-vitro
Testing
Authors: Fitzgerald Seán , Dai Daying , Douglas Andrew S , Mereuta Oana M , Caracena Thomas , Rizvi Asim , Kaufmann Ella C , Jensen Taitelynn E , Klingele Connor , Kadirvel Ramanathan , Kallmes David F , Doyle Karen M , Brinjikji Waleed
Published: June 2021

Introduction:
Previous studies have successfully created blood clot analogues for
In-vitro
testing using animal blood. Blood components vary greatly among species and thus, creating clot analogues with human blood is likely a more accurate representation of thrombi formed in the human vasculature. We present a novel method of creating clot analogues from human blood and platelets that mimic the process by which clots form
In-vivo
.

Methods:
Following IRB approval from Mayo Clinic, human whole blood and platelets donations were obtained from the Blood Transfusion service. The whole blood was centrifuged at 1,200RPM for 20 minutes to separate it into its constituents. Plasma was removed and the remaining Red Blood Cells and Buffy Coat were mixed together by inverting. A total of 12 clot analogues were created with varying concentrations of components; Red Blood cells/Buffy Coat, Plasma and Platelets. Thrombin was added first to stimulate platelets activation for a total of 5 mins whilst continuously mixing by inversion. The RBC/WBC mixture was added next followed by CaCl2. The mixture was then quickly drawn into a 3cc syringe and spun overnight at 20RPM at room temperature to mimic dynamic flow conditions. Macro-photographs were taken to display the variation in texture and color between different clot analogue types. The clots were then fixed in 10% neutral buffered formalin for 24 hours prior to being processed. Histopathological analysis was performed using Hematoxylin and Eosin (H&E) and Martius Scarlet Blue (MSB) staining to confirm clot composition.

Results:
Red Blood cell-rich, Fibrin-rich, Platelet-rich and mixed clot analogues that accurately mimic clots retrieved from Acute Ischemic Stroke Patients were created. The range of histopathological compositions of the clot analogues is similar to that of the clinical samples.

Conclusions:
The addition and activation of platelets is key to creating accurate clot analogues for
In-vitro
testing. Spinning the clots is important to prevent natural sedimentation and mimic the
In-vivo
situation.
Abstract WP12: Endovascular Thrombectomy for Acute Ischemic Stroke Associated With Cervical Artery Dissection: A Systematic Review and Meta-Analysis
Authors: Dmytriw Adam A , Maingard Julian , Phan Kevin , Mobbs Rajph J , Brooks Mark , Chen Karen , Hirsch Joshua , Barras Christen , Chandra Ronil , Asadi Hamed
Published: June 2021

Objectives:
Strokes associated with cervical artery dissection have been managed primarily with antithrombotics with poor outcomes. The additive role of endovascular thrombectomy remains unclear. The objective was to perform systematic review and meta-analysis to compare endovascular thrombectomy and medical therapy for acute ischemic stroke associated with cervical artery dissection.

Methods:
Studies from six electronic databases included outcomes of patient cohorts with acute ischemic stroke secondary to cervical artery dissection who underwent treatment with endovascular thrombectomy. A meta-analysis of proportions was conducted with a random-effects model. Modified Rankin score at 90 days (mRS 0-2) was the primary outcome. Other outcomes included proportion of patients with thrombolysis in cerebral infarction (TICI) 2b-3 flow, 90-day mortality rate, and 90-day symptomatic intracerebral hemorrhage (sICH) rate.

Results:
Six studies were included, comprising 193 cases that underwent thrombectomy compared with 59 cases that were managed medically. Successful recanalization with a pooled proportion of thrombolysis in cerebral infarction (TICI) 2b-3 flow in the thrombectomy group was 74%. Favorable outcome (mRS 0-2) was superior in the pooled thrombectomy group (62.9%, 95% CI 55.8-69.5%) compared medical management (41.5%, 95% CI 29.0-55.1%, P=0.006). The pooled rate of 90-day mortality was similar for endovascular vs medical (8.6% vs 6.3%). The pooled rate of symptomatic intracranial haemorrhage (sICH) did not significantly differ (5.9% vs 4.2%, P=0.60).

Conclusions:
Current data suggest that endovascular thrombectomy may be an option in patients with acute ischemic stroke due to cervical artery dissection. This requires further confirmation in higher quality prospective studies.
Abstract WP125: Association of 24-Hour Systolic Blood Pressure Parameters Post-Intravenous Alteplase With Functional Outcomes at Discharge
Authors: Nisar Taha , Tofade Toluwalase , Liberman Ava , Khandelwal Priyank
Published: June 2021

Introduction:
Elevation of post-stroke systolic blood pressure (SBP) can be a part of a compensatory mechanism to restore cerebral perfusion to the ischemic brain tissue, but comes at a risk of reperfusion injury. The ideal SBP in the 24-hour range post-IV-rtPA has been understudied. We investigated the association of different SBP parameters post-intravenous-alteplase (IV-rtPA) with the functional outcome at discharge at a tertiary care center.

Methods:
We performed a retrospective chart review of patients with an acute ischemic stroke treated with IV-rtPA at a comprehensive stroke center from July 2014 to March 2018. We excluded patients who underwent mechanical thrombectomy. At the comprehensive stroke center, the BP values are documented according to standard post-IV-rtPA care guidelines. We recorded the SBP values over a period of 24-hours post-IV-rtPA. A binary logistic regression analysis was performed, controlling for age, sex, pre-treatment NIHSS, atrial fibrillation, onset to treatment time, with the SBP parameters as the predictors. The primary outcome was the functional outcome at discharge. Good outcome was defined as a modified rankin scale (mRS) of ≤2 and a poor outcome as mRS of ≥3, upon discharge.

Results:
84 patients met our inclusion criteria. 45 (53.57%) patients were male. The mean age was 63.50±15 years. 25 (29.76%) patients had a good outcome (mRS≤2) at discharge. In our cohort, the parameters of higher mean SBP (144.9±14 vs.135.5±18; OR, 1.06; 95% CI, 1.02-1.11; P 0.004), higher maximum SBP (176.56±17 vs.166.7±18; OR, 1.06; 95% CI, 1.02-1.1; P 0.005) and wider pulse pressure (65.5±12 vs.57.8±13; OR,1.08; 95% CI, 1.03-1.14; P 0.007) were significantly associated with a poor outcome at discharge. Parameters of SBP variability like standard deviation SBP (13.5±5 vs.11.5±4; OR, 1.17; 95% CI, 1-1.36; P 0.058), coefficient variation SBP (9.36±4 vs.8.49±3; OR, 1.11; 95% CI, 0.94-1.32; P 0.242), and SBP range (62.22±20 vs.54.68±15; OR, 1.04; 95% CI, 1-1.07; P 0.08) were not significantly associated with a poor outcome at discharge.

Conclusions:
Our study demonstrates an association between higher mean SBP, higher maximum SBP, and wider pulse pressure over a period of 24-hours post-IV-rtPA, and poor functional outcome upon discharge.
Abstract WP134: 3K3A-APC Protects Pericyte-deficient Mice From Ischemic Brain Injury
Authors: Wang Yaoming , Huuskonen Mikko , Montagne Axel , Zlokovic Berislav
Published: June 2021

Pericytes play a key role in maintaining the blood-brain barrier (BBB) integrity. BBB disruption occurs during early stages after ischemic stroke. However, the role of pericytes in the pathogenesis of ischemic stroke remains still understudied. 3K3A-APC, a recombinant variant of activated protein C, has shown benefits in preclinical models of ischemic stroke and has favorable safety profile and reduces hemorrhage in Phase 2 study in ischemic stroke patients (RHAPSODY). In the present study, we used PDGFRβ heterozygous knockout (PDGFRβ+/-) mice to investigate the effects of pericyte deficiency on ischemic brain injury using transient proximal middle cerebral artery occlusion (tMCAO). Additionally, we investigated the effects of 3K3A-APC therapy (0.2mg/kg i.v. 4h after stroke) in this model. Compared to controls, pericyte deficiency in PDGFRβ+/- mice resulted in ~35% increase in the infarct and edema volumes, reduction in pericyte coverage from 58% to 25%, and increased IgG and fibrin deposition suggesting accelerated BBB breakdown 24h after stroke. Additionally, PDGFRβ+/- mice showed by 36% more degenerating Fluoro-Jade+ neurons and exhibited accelerated neurobehavioral abnormalities. 3K3A-APC improved neuropathological changes and functional deficits. Our results suggest that pericyte deficiency worsens brain damage and functional outcome after ischemic stroke in mice suggesting that pericytes may play an important role in protecting brain from post-ischemic. We also suggests that 3K3A-APC protects pericyte function in stroked mice which could contribute to its overall neuroprotective effects.
Abstract WP138: Intermittent Fasting Prevents Ischemic Progression and Promotes Long-Term Recovery
Authors: Chelluboina Bharath , Mehta Suresh L , Chokkalla Anil K , Bathula Saivenkateshkomal , Park Jin Soo , Vemuganti Raghu
Published: June 2021

Intermittent fasting (IF) showed a substantial benefit in preventing vascular complications in both humans and animal models. We currently evaluated the effect of IF on post-stroke ischemic progression and motor dysfunction. Cohorts of adult male C57BL/6 mice were subjected to IF (16 h fasting and 8 h feeding) or ad libitum (AL) feeding for 45 days. Mice were subjected to one hour transient middle cerebral artery occlusion (MCAO) on day 45. Infarct size was measured on day 1 and 7 with T2-weighted 4.5T magnetic resonance imaging and Image J software with multi FDF opener plugin. Post-stroke motor deficits were evaluated with rotarod and beam walk tests between days 1 to 14 of reperfusion. Long-term post-stroke survival (till 90 days of reperfusion) was noted in both groups. IF group showed a significant decrease in body weight (by ~5.3g), soft weight (by ~5.6g), and lean weight (~8.1g) compared to AL group as identified by DEXA scanning on day 45 (n=6/group, *p<0.05 by ANOVA with Bonferroni’s multiple comparisons test). The IF group showed significantly decreased brain infarction at both day 1 and day 7 of reperfusion (AL group showed 43% and 39% infarct size on days 1 and 7 while IF group showed 24% and 7.5% infarction on days 1 and 7; n=6-8/group, *p<0.05 by ANOVA with Bonferroni’s multiple comparisons test.) IF cohort also showed significant improvement in post-stroke motor dysfunction identified by fewer foot faults (beam walk test) and more time on rotarod between days 1 to 14 of reperfusion compared with AL cohort. At day 90 of reperfusion, IF mice showed a high survival rate than AL mice (08 of 10 IF mice survived while 04 of 10 AL mice survived). Thus, our studies show that IF significantly preconditions the brain against post-stroke damage and improves the long term functional outcome.
Abstract WP139: Intranasal Administration of Mesenchymal Stem Cell (MSC)-Derived Exosomes Confers Acute Neuroprotection After Neonatal Stroke
Authors: Pathipati Praneeti , Faustino Joel , Lecuyer Matthieu , Strivelli Jacqueline , Phinney Donald , Vexler Zena
Published: June 2021

Background:
Brain injury caused by stroke is a surprisingly common occurrence in neonates and is associated with significant long-term disabilities. We and others have shown delayed mesenchymal stem cell (MSC)-based therapy to be beneficial after neonatal stroke. Mounting evidence suggests MSC-derived soluble factors as key mediators of their neuroprotective/regenerative effects. We wanted to test whether Exosomes (Exo) derived from MSC carry beneficial effects after neonatal stroke.

Objectives:
Characterize effects of intranasal administration of MSC-derived Exo after neonatal stroke.

Methods:
MSCs enriched from the bone marrow of C57Bl6 mice (immuno-depletion) were cultured for 3 days in Exo-free FBS and confirmed by flow cytometry to be CD44
+
/CD29
+
and CD11b
-
/CD45
-
. Exo were isolated (ExoQuick, SBI), their size distribution determined (NanoSight™), and Exo labeled with CellVue® before intranasal administration. Postnatal day 9 (P9) mice were subjected to a 3h middle cerebral artery occlusion (tMCAO), Exo (5ug, 1uL in PBS) administered into the nostril ipsilateral to injury, and injury volume and cell types that uptake Exo determined.

Results:
By 24h after administration, labelled Exo were visible ipsilateral along the lateral ventricle, in the SVZ, corpus callosum and in the penumbra, localized largely to Glut1
+
-vessels and Iba1
+
-microglia (MG). By 72h, labeled Exo were predominantly localized in Iba1
+
-MG peri-infarct. Very few Exo were seen contralateral. Compared to vehicle/untreated mice, intranasal Exo significantly reduced injury volume at 72h (p<0.01, n=5). Preliminary in vitro experiments using MG isolated from acutely injured neonatal brain (CD11b-conjugated beads) confirmed significantly higher Exo uptake by MG from the ipsilateral Vs. contralateral cortex (p<0.05, n=2).

Summary:
We demonstrate that MSC-Exo exert short-term protection against neonatal stroke and that the magnitude of Exo uptake depends on the status of MG activation after injury. We are characterizing longer-term effects of MSC-Exo on stroke outcome to further explore potential for intranasal MSC-Exo as a clinically suitable therapeutic option for neonatal stroke.

Funding:
CPA PG0816 (ZV); AHA Innovation Award 17IRG33430004 (ZV); R01HL139685 (ZV)
Abstract WP147: Cell-Free Fat Extract Promotes Angiogenesis in a Mouse Model of Cerebral Ischemia
Authors: Shen Hui , Yang Guo-Yuan , Tang Yaohui , Zhang Zhijun , Yu Ziyou , Zhang Wenjie
Published: June 2021

Background:
Adipose tissue and its derivatives including adipose-derived stem cells and stromal vascular fraction (SVF) showed effective in the treatment of ischemic stroke. However, cell-based therapy for clinical application has been hindered by limitations such as safety, immunogenicity issues, and difficulties in cell preservation, transportation, and phenotype control. Here, we aimed to produce a cell-free extract directly from human fat tissue and evaluate its potential therapeutic efficacy for treating ischemic stroke.

Methods:
Cell-free aqueous extract from human fat tissue was obtained using mechanical emulsification method. Twenty adult CD-1 mice were subjected to 60-minute middle cerebral artery occlusion. Immediately after ischemia, 0.1 ml fat extract was intravenously injected into ischemic mice through tail vein every other day for 14 days. Brain atrophy volume and neurobehavioral outcomes were examined at 14 days after focal ischemia. The occurrence of angiogenesis was evaluated by immunostaining and ELISA, and growth factors contained in the fat extract was analyzed to explore the molecular mechanism of fat extract treatment.

Results:
Our results showed that brain atrophy volume reduced and neurobehavioral outcomes improved at 3 ,7 and 14 days of focal ischemia in the fat extract treated mice compared to the controls (
p
<0.05). Furthermore, fat extract treatment increased microvessel density at 14 days after focal ischemia (p<0.05). ELISA showed that fat extract contained high levels of several growth factors such as HGF, VEGF, bFGF, BDNF, and GDNF.

Conclusions:
We developed a novel cell-free therapeutic agent, fat extract, produced from human adipose tissue. The fat extract contained high level of growth factors such as HGF, VEGF, bFGF, BDNF, and GDNF, which plays important role of promoting angiogenesis and reduced ischemic brain injury in the mouse brain, suggesting that the fat extract is a novel cell-free therapeutic agent in the treatment of ischemic stroke.
Abstract WP151: Rapamycin Improves Post-Recanalization Blood Flow After Acute Experimental Stroke in Rats
Authors: Schneider Anna Maria , Beard Daniel , Buchan Alastair
Published: June 2021

Background and Purpose:
In the era of thrombectomy, there is evidence suggesting that successful recanalization is not always accompanied by complete reperfusion, the so called “no-reflow phenomenon”. Given the importance of reperfusion as a predictor of stroke outcome, this represents a potential target for stroke therapy. Rapamycin, a clinically approved inhibitor of Mammalian Target of Rapamycin (mTOR) has been shown to improve cerebral blood flow (CBF) in Alzheimer’s disease. However, there has been little investigation into the effect of rapamycin on post-stroke microvascular perfusion. The aim of this study was to investigate the effects of rapamycin treatment on post-recanalisation CBF and stroke outcome in an experimental animal model of stroke.

Methods:
Male Wistar rats (300-350g) were subjected to 90min of transient middle cerebral artery occlusion (tMCAo) followed by randomized administration of 250μg/kg intravenous rapamycin (n=8) or vehicle (n=6), 30min after the onset of MCAo. Laser Doppler flowmetry was used to continuously measure changes in MCA perfusion during MCAo and for min after recanalisation. Neurobehavioral tests were performed 24hrs after MCAo before tissue was collected for infarct volume measurement.

Results:
MCAo was confirmed by a 70% reduction in MCA perfusion. Rapamycin treatment significantly improved post-recanalization CBF at 55min after recanalization (p<0.01). Rapamycin significantly increased average CBF during the 60min post-recanalization period (p<0.01). Rapamycin showed a trend towards reduced final infarct volume. Rapamycin significantly improved neuroscores (p<0.05). Post-recanalization CBF was significantly inversely correlated with infarct volume (R
2
=0.4994, p<0.05).

Conclusion:
Rapamycin significantly improved post-recanalization CBF and behavioural outcomes after MCAo. These results suggest that rapamycin may be an effective acute intervention to improve post-recanalisation blood flow to improve stroke outcome. However, further studies are need to determine the mechanism of improved CBF and if improvements in post-stroke CBF and neurological outcome are sustained long-term post-stroke.
Abstract WP152: Novel Therapy With Pdgf-b Nanoparticles for Cerebral Infarction
Authors: Takagishi Soh , Arimura Koichi , Iwaki Katsuma , Nishimura Ataru , Murata Masaharu , Iihara Koji
Published: June 2021

Background and Purpose:
Treatment for cerebral infarction beyond the indication of reperfusion therapy has not yet been established, and novel approaches are needed. It has been reported that platelet-derived growth factor (PDGF)-B played a neuroprotective role by enhancing cell survival and tissue repair for a long period after cerebral infarction in experimental animal models. However, PDGF-B is difficult to administer at effective concentrations in infarct area. In general, nanoparticles are very small and stable, making them prone to accumulation without being metabolized in infarct area. Therefore, we converted PDGF-B into nanoparticles and examined its therapeutic effect for cerebral infarction.

Methods:
PDGF-B nanoparticles (PDGF-B NP) and wild-type nanoparticles (wNP) were injected one day after transient middle cerebral artery occlusion (tMCAO) using the CB-17 mouse model. We analyzed temporal histological changes and neurological function recovery. Fucntional recovery was assess using Cylinder test at 3 and 7 days after the tMCAO. As for the mechanism of neuroprotective effect, phosphorylation of Akt, neurotrophin-3 (NT-3), and expression of angiogenesis were also examined in the infarct area and compared them with wNP control at 7 days after tMCAO.

Result:
We found that PDGF-B NP was distributed specifically in the infarct area. As compared with wNP group, PDGF-B NP group significantly suppressed cerebral infarct volume and improved neurological function at 3 and 7 days after cerebral infarction compared with wNP group. Akt was strongly phosphorylated in the infarction area with PDGF-B NP administration compared with wNP. Moreover, PDGF-B NP significantly induced angiogenesis, NT-3 expression, and reduced cell apoptosis after cerebral infarction compared with wNP.

Conclusion:
PDGF-B NP activated PDGF-B-Akt signaling in infarct area and played various important roles leading to neuroprotection after cerebral infarction. Our results suggested that treatment with PDGF-B NP may be useful for cerebral infarction beyond reperfusion therapy.
Abstract WP153: Post-Stroke Physical Exercise Improves Cognition in Middle-Aged Female Rats
Authors: Saravanan Sharnikha , Zhao Weizhao , Dave Kunjan R , Perez-Pinzon Miguel A , Raval Ami P
Published: June 2021

Background:
A woman’s risk of a stroke increases exponentially following the onset of menopause, andpost-stroke cognitive decline is a significant consequence of stroke survivors. Our earlier study demonstrated that physical exercise (PE) reduced post-stroke brain injury and improved cognitive functions in male rats. The focus of our study is on the improvement of post-stroke cognitive function in female rats.

Methods:
Reproductively senescent Sprague-Dawley female rats were exposed to transient middle cerebral artery occlusion (tMCAO; 90 min) and randomly assigned to either PE or sham-PE groups. After 3-5 days, rats underwent sham-PE (0m/min speed) or PE (15m/min speed) for 30 mins either every day (continuous) or alternate day for five times on treadmill. The rats that underwent the alternate day paradigm were treated with ER-β agonist (DPN; 1mg/kg) or vehicle-DMSO immediately following PE/sham-PE sessions to determine the synergistic effect. Twenty-one days after the last PE/sham-PE, rats were tested for hippocampal-dependent contextual fear conditioning and freeze time was measured. Rat brains were processed for histology and infarct area was measured with MCID software. From a separate cohort of rat subjected to PE or sham-PE, brain tissue was harvested for various biochemical assays and mitochondrial enzyme activity measurements.

Results:
Post-tMCAO continuous PE did not reduce ischemic damage. However, alternate PE regimen with or without ER-β agonist reduced infract volume by 20% (p < 0.05) and 23% (p < 0.05), respectively as compared to no-PE. Similarly, alternate PE showed increased freezing on the second day of fear conditioning by 15% (p < 0.05), indicating improved spatial memory. Individual mitochondrial complex I, II, III and IV enzyme activity measurements demonstrated significant improvement in complex III-IV enzyme activities in the alternate PE treated group as compared to sham-PE.

Conclusion:
An alternate day PE paradigm and ER-β activation improves post-stroke mitochondrial enzyme activities and cognition in reproductively senescent female rats. Future studies delineating underlying mechanism could help identify therapies to prevent/reduce cognitive decline in menopausal female stroke patients.
Abstract WP157: Neuregulin-1 Stimulates Breast Carcinoma Amplified Sequence 1+ Pre-Myelinating Oligodendrocytes Following Ischemic Stroke
Authors: Noll Jessica , Ford Byron
Published: June 2021

Stroke is ranked as the fifth leading cause of death and the leading cause of adult disability in the United States. Tissue Plasminogen Activator (tPA) is the only FDA approved stroke treatment. Unfortunately, tPA is only administered to 2-5% of patients due to risk of hemorrhage, and it has no therapeutic effect on neuroprotection or neurological recovery. Thus, there is no treatment capable of addressing progressive adult disability. However, it has been shown that exogenous Neuregulin-1 (NRG-1) significantly decreases acute neuronal death and neuroinflammation after ischemic injury. Furthermore, NRG-1 has demonstrated a neuroregenerative effect with increased neuronal sprouting, synapse formation markers, and functional recovery after ischemia. NRG-1 also plays critical roles in oligodendrocyte differentiation, survival, and maturation, suggesting that treatment would further enhance remyelination after ischemic injury. In this study, we examined the effect of NRG-1 treatment on a transient pre-myelinating BCAS1+ oligodendrocyte population. BCAS1 is expressed along oligodendrocyte processes when actively myelinating and exhibits a bushy morphology. Mice were given permanent middle cerebral artery occlusion (MCAO) and administered intra-arterial NRG-1(10ug/kg) or equivalent vehicle (0.1% BSA) at the time of reperfusion. Mice were sacrificed 24 hours post-stroke and ischemic lesion was exhibited with Triphenyl tetrazolium chloride (TTC). Immunohistochemistry with FluoroJade B and TUNEL was used to quantify the infarct size. Oligodendrocytes were evaluated with anti-Olig2 and anti-BCAS1. We showed that pre-myelinating BCAS1+ oligodendrocyte populations are present within the sham striatum and cortex but disappear in the injured striatum and cortex after stroke. However, this population increases within the ipsilateral peri-infarct cortex and throughout the contralateral hemisphere. NRG-1 treated mice exhibited an increase in BCAS1+ oligodendrocytes within the injured cortex compared to vehicle treated mice after 24 hours. Thus, NRG-1 may stimulate localized oligodendrocyte differentiation and early remyelination after stroke, suggesting a role as a regenerative agent.
Abstract WP164: National Estimates of Recurrent Ischemic Stroke Among Patients Undergoing Carotid Revascularization: Effect of Treatment Modality
Authors: Chaudhry Saqib A , Fang Yun , Hassan Ameer E , Akhtar Iqra N , Chaudhry Mohammad Rauf A , Gill Mohsain , Suri Fareed K , Siddiq Farhan , Gomez Camilo R , Qureshi Adnan I
Published: June 2021

Background:
The estimates of recurrent ischemic stroke in the post-hospitalization period among patients treated for carotid revascularization are not available outside clinical trials (real-world settings).

Objective:
To determine the rates of ischemic stroke-related hospitalization within 3 months post-hospitalization for treatment of carotid stenosis in a nationwide cohort.

Methods:
We identified all readmissions related to new ischemic stroke in the nationally representative data for all patients hospitalized for carotid revascularization using the Nationwide Readmissions Database (NRD) 2013 and 2014 for carotid stent placement (CAS) and carotid endarterectomy (CEA). Cox proportional hazards analysis was used to assess the relative risk (RR) of recurrent ischemic stroke for patients in treatment cohorts after adjusting for potential confounders. The survival was estimated for both treatment groups by using Kaplan-Meier survival method.

Results:
A total of 120, 923patients with carotid stenosis were treated with either CAS (n = 15, 819; 13.1%) or CEA (n = 105,103; 86.9%).- The estimated 3 month recurrent ischemic stroke free survival was 99.2% and 98.9% in patients who underwent CEA and CAS treatments, respectively (p= 0.014). After adjusting for age, and APDRG severity score, the RRs of recurrent any ischemic stroke was higher women (RR, 1.3; 95% confidence interval (CI), 1.1 -1.6), symptomatic patients (RR, 1.5; 95% CI, 1.1 -2.1) and weekend admission (RR, 1.6; 95% CI, 1.1 -2.3).

Conclusion:
Although the rates of recurrent ischemic stroke-related hospitalization were low among patients undergoing carotid revascularization, there were higher rates among women, symptomatic patients, undergoing carotid stenting and those admitted on weekends.
Abstract WP178: The Presence of Arterial Stenosis in Posterior Reversible Encephalopathy Syndrome
Authors: Scarsella Monica , Purohit Meghan , Mullaguri Naresh , Jillella Dinesh , Uchino Ken
Published: June 2021

Introduction:
Posterior Reversible Encephalopathy Syndrome (PRES) is defined as reversible vasogenic cerebral edema in a characteristic posterior-dominant distribution in patients presenting with focal neurologic findings. It has been shown that some patients with PRES have transient arterial stenosis.

Objectives:
To determine the prevalence of arterial stenosis in PRES patients and demonstrate if patients with arterial stenosis define a subpopulation within PRES.

Methods:
We searched patients with PRES in electronic health records at a single health system from January 2008 to December 2018. Inclusion criteria were age 18 years or older with clinical and radiographic evidence of PRES and arterial imaging (CT or MR angiography or cerebral angiogram.) Age, presenting symptoms, comorbid conditions, and imaging findings were compared between those with arterial stenosis and those without.

Results:
Of 74 patients diagnosed with PRES, 46 had arterial imaging. Arterial stenosis was seen in 28.3% (13/46) of these patients. Stenoses improved in all 4 patients who had followup imaging, 3 with complete resolution. The arterial stenosis group was younger (median age 32 years with arterial stenosis vs 57.5 years without, p= 0.011.) Patients with arterial stenosis did not differ in frequency of presenting symptoms of seizure, encephalopathy, or focal neurologic deficits, nor did they differ in comorbid conditions of hypertension, immune suppression, eclampsia/preeclampsia, or antidepressant use. There were no differences in ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, or frequency of diffusion restriction on MRI between the groups. The occurrence of >50% FLAIR reversibility was less frequent among those with arterial stenosis (40%) than in those without arterial stenosis (81%, p=0.04.)

Conclusions:
A quarter of patients with PRES had transient arterial stenosis. These patients represent a subgroup within PRES patients who are younger age, but lower frequency of reversibility of parenchymal imaging abnormality.
Abstract WP183: Borderzone Infarcts Predict Early Recurrence in Patients With Large Artery Atherosclerotic Subtype Despite Medical Treatment
Authors: Kvernland Alexandra , Prabhakaran Shyam , Khatri Pooja , De Havenon Adam , Yeatts Sharon , Scher Erica , Pirooz Sahnaz , Torres Jose , Ishida Koto , Frontera Jennifer , Lord Aaron , Liebeskind David S , Yaghi Shadi
Published: June 2021

Introduction:
Large artery atherosclerosis subtype carries a high risk of early recurrent stroke despite medical management. Predictors of recurrence remain poorly understood. We hypothesized that borderzone infarcts are associated with a higher risk of recurrence.

Objectives:
We aim to investigate infarct patterns and 90-day recurrence in patients with symptomatic intracranial and/or extracranial atherosclerotic disease.

Methods:
We included consecutive patients admitted to NYU Langone Health (Manhattan and Brooklyn campuses) over 32-months with a diagnosis of acute ischemic stroke secondary to symptomatic intracranial or extracranial atherosclerosis. The primary predictor was infarct pattern (borderzone vs. non-borderzone infarction), defined in accordance to previous studies. Borderzone infarcts were divided into internal borderzone and cortical borderzone. We used univariate and multivariable cox-regression models to determine associations between infarct pattern and recurrent cerebrovascular events (RCVE) at 90-days.

Results:
Fifty-five patients met the inclusion criteria; 38 were intracranial, 3 tandem, 14 extracranial. Nearly 71% of patients were treated with dual antiplatelet therapy and 96% were treated with high intensity statin. The RCVE rate was 23.6%. In multivariable models, borderzone infarcts were associated with increased risk of RCVE (adjusted HR 9.8 95% CI 2.1-44.8, p=0.003). The risk of RCVE was highest among internal borderzone infarcts (47.3%) as opposed to cortical borderzone infarcts (33.3%) or non borderzone infarcts (18.8%).

Conclusions:
Borderzone (and particularly internal borderzone) infarcts are a surrogate marker of impaired distal blood flow and are associated with RCVE despite medical treatment. This highlights the need to develop alternate treatment strategies for this high-risk cohort.
Abstract WP194: Interference of Cognitive Tasks and Upper Limb Movements in Chronic Stroke Patients: A Dual-Task Study
Authors: Kim Hogene , Kim Hyunki , Kim Na Young , Choi Hyun , Shin Joonho , Nam Chang
Published: June 2021

Background:
This study investigated cognitive-motor interference effects after a chronic stroke diagnosis.

Methods:
Ten stroke patients (54.7±12.3 yrs.) and seven age-matched controls (58.4±10.6 yrs.) took part in a series of cognitive-motor tasks. Under single-motor task conditions, participants moved a cursor of the robot arm along the annulus using unaffected hand (
Circle
task), or performed a center-out movement in four directions (
Cross
task). Under single-cognitive task conditions, participants performed the Serial 7 (S7 task) or the Controlled Oral Word Association Test (COWAT task). Under dual-task conditions, participants performed a motor task and a cognitive task simultaneously. The movement accuracy, defined as the percent of movement trajectories within the annulus per total movement trajectories, were measured on motor tasks, and the number of correct answers were recorded on cognitive tasks.

Results:
Results of two-sample t statistic showed that the movement accuracy of the stroke group was lower than that of the control group, in particular under single-motor conditions (Circle: stroke 84.9±11.2% vs control 93.1±5.1%, p=0.094; Cross: stroke 77.2±13.2% vs control 88.6±8.2%, p=0.062). No significant difference was found between the control and stroke groups under single-cognitive task conditions. The control group showed no significant changes in the number of correct answers and movement accuracies between single and dual tasks. On the other hand, the stroke group showed significantly decreased movement accuracy for the Cross task compared to the Circle task (p=0.006). The stroke group’s number of correct answers in the S7 task were significantly decreased when S7 was performed together with the Cross task (10.0±5.3 vs 8.1±4.5, p=0.008). Their movement accuracy was also significantly reduced under dual-task conditions (single 77.2±13.2%, dual (COWAT+Cross) 74.6±12.4, p=0.034).

Conclusions:
This study confirmed that cognitive-motor interference is evident for stroke patients when they performed a cognitive task and a motor task simultaneously, such that performance in one or both of the dual tasks is worse as compared to that of each single task.
Abstract WP21: “Stunned Brain”– Early versus Delayed Clinical Recovery After Neurothrombectomy
Authors: Desai Shashvat , Morrison Andrew A , Starr Matthew , Molyneaux Bradley J , Rocha Marcelo , Gross Bradley A , Jankowitz Brian T , Jovin Tudor G , Jadhav Ashutosh P
Published: June 2021

Introduction:
Heterogeneity in early neurological improvement after neurothrombectomy for large vessel occlusion (LVO) stroke is well documented. Delayed clinical recovery is observed in a subset of patients who do not experience early improvement. Understanding the temporality of clinical recovery after thrombectomy is essential in guiding prognostication and targeting rehabilitation. In this study, we aim to describe the characteristics and incidence of early and delayed clinical recovery and identify their predictors after LVO stroke thrombectomy.

Methods:
A retrospective analysis of prospectively-collected data on patients undergoing anterior circulation LVO stroke thrombectomy. Demographic characteristics, clinical and radiological data, treatment and procedural information were extracted and analyzed. Characteristics and predictors of early clinical recovery (ECR-1-NIHSS <6 at 24 hours and ECR-2-mRS 0-2 at discharge) and delayed clinical recovery (DCR-1 and 2- mRS 0-2 at 90 days) were analyzed. Statistical analyses were performed on SPSS 23 (IBM, Armonk, NY).

Results:
Three hundred and fifty-five patients met study criteria. 55% (195) were females and mean age was 71±15 years. Mean NIHSS score and median ASPECTS were 17±6 and 9 (8-10), respectively. ECR-1 and ECR-2 were observed in 31% (115) and 21% (73) patients, respectively. Among non-ECR patients, delayed recovery was observed in 27-30% of patients. Lower NIHSS [OR-0.83 (0.75-0.91), p=<0.01] and higher ASPECTS [OR-2.14, (1.29-3.54), p=0.003] scores were independent predictors of ECR-1 and younger age [OR-0.96 (0.94-0.99), p=0.01] and absence on parenchymal hemorrhage (PH) [OR-3.1 (1.3-7.1), p=0.007] were independent predictors of DCR-1. Among non-early improvers, patients <80 years and without PH have a 40% chance of DCR compared to no patients over 80 years with parenchymal hemorrhage experiencing DCR.

Conclusion:
About one-third of patients experience early clinical recovery (ECR-1-31%) and approximately one-third (DCR-1-30%) of non-early improvers experience delayed clinical recovery. Lower NIHSS score and higher ASPECTS predict ECR while younger age and absence of parenchymal hemorrhage predict DCR.
Abstract WP212: Arterial Stiffness is Associated With Apolipoprotein B 100, Not LDL-Cholesterol in Patients With Acute Ischemic Stroke
Authors: Park Kwang-Yeol , Kim Jeong-Min
Published: June 2021

Background:
Arterial stiffness has been reported to be associated with hypertension, vascular disease including cerebral small vessel disease and increased mortality. Also, dyslipidemia is one of the potent risk factors for atherosclerosis. We aim to investigate the association of arterial stiffness and various lipid fractions including low density lipoprotein cholesterol (LDL-cholesterol), lipoprotein(a), and apolipoprotein B 100 in patients with acute ischemic stroke.

Methods:
We identified 2187 consecutive patients with acute ischemic stroke confirmed on MR imaging or CT. Brachial-ankle pulse wave velocity (baPWV) was measured using a volume-plethysmography device (VP-1000; Collin, Komaki, Japan). Lipid fractions were measured with blood sample taken after at least 8-hour fast. Vascular risk factors and demographics of patients were assessed by our prospectively collected stroke database. The association between baPWV and lipid fractions was tested using linear regression analysis.

Results:
Mean age of patients was 68.5 +/- 12.3 years and male was 1214 (55.5%). Mean baPWV was 20.85 +/- 5.55 m/sec. On simple regression analysis, baPWV was associated with lipoprotein(a) and LDL-cholesterol (p < 0.05). However, on multivariable linear regression adjusting for age, sex, lipid fractions and other vascular risk factors, apolipoprotein B 100 was the only significant lipid fraction for baPWV (beta 1.42; 95% confidence interval 0.45 - 2.40; p < 0.001). We included LDL-cholesterol instead of apolipoprotein B 100 in another model due to multicollinearity, which showed that neither LDL-cholesterol nor lipoprotein(a) was significant.

Conclusion:
Among lipid fractions, apolipoprotein B 100 is associated with systemic arterial stiffness in patients with acute ischemic stroke. Our finding suggests that apolipoprotein B 100 might be a better predictor for arterial stiffness than LDL-cholesterol and lipoprotein(a).
Abstract WP220: Can’t Breathe, Can’t See, Can’t Think: Chronic Obstructive Pulmonary Disease Increases the Risk of Posterior Reversible Encephalopathy Syndrome
Authors: Bates Molly , Darpel Kyle , Amadife Nneka , Dugan Adam , Lee Jessica D
Published: June 2021

Introduction:
Several theories exist regarding the pathogenesis of posterior reversible encephalopathy syndrome (PRES). One theory suggests that PRES occurs when systemic blood pressure exceeds the upper limit of cerebral autoregulation. Endothelial dysfunction has been proposed as an alternative pathogenesis to account for PRES outside the setting of acute hypertension. This mechanism has been implicated in other conditions associated with PRES including autoimmune diseases, cytotoxic medications, sepsis, and eclampsia. The purpose of this study was to determine if COPD, a disease known to cause endothelial dysfunction, has a causative association with the development of PRES.

Methods:
A single center retrospective, age-matched, case-control study was performed from January 2013 to June 2019 comparing patients discharged with a primary diagnosis of PRES to a control group with acute ischemic stroke. Demographics, medical comorbidities, initial blood pressure, and clinical outcomes were compared between the two groups. For categorical variables, p-values were calculated using χ2 and Fisher’s exact tests. For continuous variables, p-values were calculated using two-sample t-tests. The effect of COPD and acute hypoxic respiratory failure on PRES status was investigated using multivariate logistic regression.

Results:
A total of 94 PRES subjects and 109 control subjects were included for analysis. Mean age did not differ between the two groups; however, the PRES group was more likely to be female (78.7% vs. 49.5%, p<0.001). COPD was present in 26.6% (n=25) of cases and 11% (n= 12) of controls (odds ratio 4.12, p=0.003). Occurrence of hypertension did not differ significantly between the two groups (78.0% vs 86.2%). Among patients with PRES in the setting of COPD (n=25), 60% (n=16) did not meet criteria for hypertensive emergency. Controlling for hypertensive emergency status in a multivariate logistic regression analysis, patients with COPD were 3.21 times more likely to develop PRES (p= 0.004).

Conclusions:
To our knowledge, very few reports of PRES in the setting of COPD have been described in the literature and no association of PRES and COPD has been defined to date. Our data support the role of COPD as a risk factor in the development of PRES.
Abstract WP226: The Association of Green Tea and Coffee Consumption With Mortality From Cardiovascular Disease and All Causes Among Persons With and Without History of Stroke or Myocardial Infarction: The JACC Study
Authors: Teramoto Masayuki , Muraki Isao , Shirai Kokoro , Tamakoshi Akiko , Iso Hiroyasu
Published: June 2021

Background:
Both green tea and coffee consumption have been associated with lower risks of mortality from cardiovascular disease (CVD) and all causes in general population, but little is known about those impact on persons with history of CVD. We examined the association of those consumption with these mortalities among persons with and without history of stroke or myocardial infarction in general population.

Methods:
The study subjects were 60,664 participants (896 stroke and 1751 myocardial infarction survivors and 58,017 persons with no history of stroke or myocardial infarction), aged 40-79 years at the baseline (1988-1990), who completed a lifestyle and medical history questionnaire including self-administered food frequency under the Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC Study).

Results:
During the median follow-up of 18.5 years, a total of 12,745 (7,458 men and 5,287 women) deaths including 3,737 CVD deaths were documented. Green tea and coffee consumption were inversely associated with CVD and all-cause mortality among myocardial infarction survivors as well as persons without history of stroke or myocardial infarction. After adjustment for known cardiovascular risk factors, the lower risks of mortality from CVD and all-causes associated with frequent green tea consumption (5-6 and ≥7 cups/day) or coffee consumption (≥2 cups/day) remained statistical.

Conclusions:
Both green tea and coffee consumption were inversely associated with risks of CVD and all-cause mortality among myocardial infarction survivors and persons without history of stroke or myocardial infarction.