bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TMP112: CD133+Exosome Treatment Improves Neuro-cognitive And Cardiac Function After Stroke In Female Adult Type 2 Diabetic Mice
Authors: Zacharek Alex , Chen Zhili , Powell Brianna , Culmone Lauren , Landschoot-Ward Julie , Findeis Elizabeth , Gao Huanjia , Lu Mei , Chopp Michael , Liu Zhongwu , Venkat Poornima
Published: February 2023

Background:
Cardiac complications post-stroke are common, and diabetes exacerbates post-stroke cardiac injury. In this study, we tested whether treatment with exosomes harvested from human umbilical cord blood derived CD133+ cells (CD133+Exo) improve neuro-cognitive and cardiac function in female type 2 diabetes mellitus (T2DM) mice subjected to ischemic stroke.

Methods:
Female, adult non-DM and T2DM mice were randomized to: 1) Non-DM (n=6), 2) Non-DM-stroke (n=15), 3) T2DM (n=8), 4) T2DM-stroke (n=12) and 5) T2DM-stroke+Exo (n=13). CD133+Exo (20μg/200μl PBS, i.v.) was administered 3 days after stroke. Evaluation of neurological function (mNSS, adhesive removal test), cognitive function (novel object recognition (NOR) test, odor test) and cardiac function (echocardiography) was performed, and mice were sacrificed at 28 days after stroke.

Results:
Stroke induces severe neurological deficits and significant short-term and long-term memory deficits which were worse in T2DM mice compared to non-DM mice. CD133+Exo treatment in T2DM-stroke mice significantly improves neurological function and cognitive outcome indicated by improved discrimination index in NOR test and odor test compared to control T2DM-stroke mice. T2DM-stroke induces significant cardiac dysfunction indicated by reduced left ventricular ejection fraction (LVEF) and shortening fraction (LVSF) compared to T2DM-control and non-DM-stroke mice. CD133+Exo treatment significantly improves LVEF, LVSF and heart rate and reduces left ventricular dimension compared to T2DM-stroke mice. T2DM-stroke mice exhibit significantly increased cardiomyocyte hypertrophy, cardiac fibrosis and inflammation compared to T2DM-control and non-DM-stroke mice. Treatment of T2DM-stroke with CD133+Exo significantly reduced cardiomyocyte hypertrophy, cardiac fibrosis and inflammation compared to T2DM-stroke mice. T2DM-stroke increases while CD133+Exo treatment reduces expression of serum inflammatory factors such as MMP-2, DKK-1, CRP, VCAM, CXCL5 and Cystatin-C.

Conclusions:
In T2DM-stroke mice, CD133+Exo treatment significantly improves neurological, cognitive, and cardiac function, and reduces cardiac pathological remodeling compared to T2DM-stroke control mice.
Abstract TMP113: Kynurenine-3-monooxygenase Inhibition Confers Neuroprotection After Ischemic Stroke In Aged Mice
Authors: Venna Venugopal Reddy , Quaicoe Victoria A , Delevati Colpo Gabriela , McCullough Louise D , Teixeira Antonio L
Published: February 2023

Background:
The kynurenine pathway (KP) is the major route of tryptophan catabolism in mammals. KP branches into two major pathways - one (dependent on the kynurenine aminotransferases) implicated in neuroprotection, the other (dependent on the enzyme kynurenine-3-monooxygenase (KMO) in neurotoxicity. Under physiological conditions, the neuroprotective branch is more active, but under inflammatory conditions, such as seen in stroke, metabolism is shifted through the KP via KMO to produce toxic metabolites, including quinolinic acid. Recent studies have demonstrated that stroke leads to the activation of the KP. Here we tested whether inhibiting KMO activity after stroke could prevent and/or minimize the neuronal death and improve outcomes.

Methods:
WT C57Bl6 aged male mice were subjected to a 60-minute reversible middle cerebral artery occlusion (MCAO). Tissues collected from a sub-cohort of these mice was used for metabolomics. Other sub-cohort of mice was used for pharmacological studies. For this, mice received either an inhibitor of KMO (Ro 61-8048, 40mg/kg/day i.p) or vehicle immediately after stroke, and infarct was evaluated at day 3 post-stroke. Neurological deficit scores and open field analysis was performed to assess recovery. A separate cohort of aged WT and KMO knockout (KMO-/-) mice was also subjected to MCAO and assessed for infarct and recovery at 3 days after stroke to further evaluate the involvement of KMO on outcome.

Results:
Stroke caused significant reduction in the aged brain kynurenic acid/quinolinic acid (KYNA/QUIN) ratio, suggesting activation of the neurotoxic/KMO branch of the KP pathway. KMOi treatment administered immediately after the stroke reduced ischemic infarct size (p<.05; n=8 mice/grp) and also improved spontaneous locomotor activity by 72h after stroke compared to vehicle treatment. We also found that genetic deletion of KMO reduces ischemic injury size (p<.05; n=6-7mice/grp) and improves neurological deficit scores.

Conclusions:
Inhibition or deletion of KMO reduces neuronal death and improves motor function after stroke in aged male mice. Further studies are needed to ascertain if beneficial effects of KMOi on post-stroke recovery is not due to smaller injury, using aged animals of both sexes.
Abstract TMP116: A Novel Microfluidic Model Of Ischemic Stroke Recapitulating Arterial Occlusion And Prolonged Retraction
Authors: Rassam Rassam , Mihalko Emily , Nimjee Shahid M , Shea Susan M
Published: February 2023

To our knowledge, an
ex vivo
model of thrombotic occlusion that (1) mimics arterial setting, (2) allows true occlusion, and (3) drug delivery without disturbing the thrombus does not exist. A platform with these capabilities would allow for high-throughput mechanistic study of thrombosis and thrombolysis. Here we present a microfluidic system that achieves these goals, providing a biofidelic
ex vivo
platform to study ischemic stroke.

A mold with an upstream Y and a region of stenosis was fabricated and used to manufacture microfluidic chambers. Channels were coated with collagen at the stenosis. Heparinized blood was collected from healthy human donors (N=3) and platelets were labelled with fluorescent anti-CD41. Samples were perfused at 10000/s and outflow mass collected on a scale. Occlusion was indicated by mass plateau, and thrombi were left to retract
in situ
for 0 or 6 hrs. Kinetic immunofluorescent images were captured and used to derive surface area and the image profile by averaging MFI in each pixel column. Sample from the same donor dosed with 0.7 or 7nM alteplase (ALT) was perfused using the Y inlet using a constant pressure head (1000/s; mimicking middle cerebral artery) for 120 min.

After 6 hours of post-occlusion retraction, thrombi substantially remodeled. The MFI curves (Fig 1) demonstrate even distribution of MFI post-occlusion that shifts to a central peak after 6 hr. Dosed sample from the same donor was able to be delivered upstream of the thrombus without disruption. Immediate reperfusion resulted in a reduction in thrombus surface area of (mean (SD)) 2% (10%) with 0.7nM ALT, 23% (7%) with 7nM, and 15% (1%) with vehicle. Reperfusion after 6 hrs resulted in a reduction of 14% (14%) with 0.7nM, 45% (12%) with 7nM, and 17% (8%) with vehicle.

We have established an
ex vivo
high throughput system capable of recapitulating arterial occlusion, thrombus retraction
in situ
, drug delivery, and thrombolysis. This system can be used for mechanistic inquiry and drug discovery.
Abstract TMP119: Increased Stroke Severity In A Model Of Preeclampsia Is Associated With Poor Collateral Flow, Oxidative Stress, And Elevated Thrombin
Authors: Cipolla Marilyn J , Tremble Sarah
Published: February 2023

Background:
Pregnancy is associated with an increased risk of stroke largely driven by the comorbidity of preeclampsia (PE), a hypertensive disorder that complicates 4-8% of all pregnancies. Although stroke treatment has improved in recent years, pregnant women have been excluded from stroke clinical trials and thus little is known about treatment and stroke outcome in this population. We investigated stroke outcome (infarct and hemorrhagic transformation, HT) in normal pregnancy (Preg; n=13) and in a model of preeclampsia (PE; n=6) induced by feeding pregnant Sprague Dawley rats a high cholesterol diet on gestational days 7-21. Nonpregnant (NP; n=7) rats were a control for pregnancy.

Methods:
Middle cerebral artery occlusion (MCAO) was used to induce focal ischemia for 3 hours with 1 hour of reperfusion. Perfusion deficit in the core MCA and collateral territories were measured using multi-site laser Doppler. Infarction and oxidative stress were determined by cresyl violet and 3-nitrotyrosine staining of fixed brain tissue, respectively. Endothelial oxidative stress and hemostatic factors were measured by ELISA for 8-isoprostane and thrombin.

Results:
Perfusion deficit in core MCA was similar between groups; however, collateral flow was significantly impaired in ePE vs. NP and LP: -51±8% vs. -21±15% and -25±13% (p<0.05). Infarct (%) was increased in ePE vs. NP and LP: 33±5% vs. 22±6% and 14±3% (p<0.05). Importantly, the majority of NP animals had HT (4/7), but none of the Preg or ePE suggesting pregnancy was protective of hemorrhage. The increased incidence of HT in NP was associated with increased 3-NT in brain tissue. However, 8-iso was increased in serum of ePE rats vs. NP and LP: 778±16 vs. 208±25 and 274±54 pg/mL (p<0.01), as was plasma thrombin: 6.6±1.2 vs. 0.49±0.01 and 0.56±0.01 pg/mL (p<0.01).

Conclusions:
Increased stroke severity in ePE animals was associated with poor collateral flow, oxidative stress and elevated thrombin, all of which could contribute to poor ischemic tolerance and increased infarction. Pregnancy-induced protection of HT may be due to high sex steroids that was present in both LP and ePE groups. Understanding contributors to stroke outcome in this population could help manage these high risk patients.
Abstract TMP14: Machine Learning-Enabled Detection Of Unruptured Cerebral Aneurysms Improves Detection Rates And Clinical Care
Authors: Ali Iman , Salazar-Marioni Sergio , Abdelkhaleq Rania , Niktabe Arash , Giancardo Luca , Love Christopher J , Paz Dan , Bibas Orin , Segev Omri , Sheth Sunil
Published: February 2023

Background:
Unruptured cerebral aneurysms (UCAs) have a relatively low prevalence of approximately 3%, but detection can prevent devastating consequences of subarachnoid hemorrhage. Here, we assess the performance of a machine-learning (ML) algorithm to identify UCAs and determine whether routine use of the algorithm would have improved detection rates and patient care.

Methods:
From a prospectively maintained multi-center registry across 8 certified stroke centers (1 comprehensive, 7 primary), we identified patients who underwent CT angiogram for evaluation of stroke from 3/14/21 - 11/31/21. A convolutional deep neural network (Viz.AI) trained to identify UCAs > 2mm analyzed the images. Ground truth was provided by independent expert neuroradiology read. The primary outcome was rate of UCAs detected by the ML algorithm but not detected or addressed in the clinical radiology report or clinical notes, which was determined by two independent researchers.

Results:
Among 1191 CT angiogram scans performed during the study period, 110 were flagged by the ML algorithm as possibly demonstrating an UCA, of which 36 cases were confirmed as true positive (PPV 33%). The most common locations included posterior communicating artery (22%), followed by MCA bifurcation (19%). Of these cases, 13 (26%) were not noted in the clinical radiology report or clinical notes, with a median size of 3 mm [IQR 2.7-4.4 mm], and 28 (78%) were not referred for follow up, with median size of 4.3 mm [IQR 3-9 mm]. Of the 28 cases not referred for follow up, 15 (54%) had been noted in the radiology report. 40% (6/15) of the detected but not referred cases had a diameter greater than 10mm.

Conclusion:
UCAs of sizes and intra-dural locations that may warrant treatment are frequently missed in routine clinical care. An ML algorithm that flags studies and notifies clinicians may minimize missed treatment opportunities.
Abstract TMP16: Mechanoreceptor Dysregulation Found In Human Intracerebral Aneurysms
Authors: Kondrasov Sasha , Yager Brock , Wolfe Stacey Q , Wilson John A , Zhidan Xiang
Published: February 2023

Introduction:
About 500,000 people worldwide die annually from ruptured intracranial aneurysms (IA). The pathophysiology of aneurysm formation is largely unknown. Piezo1 mechanoreceptors are expressed in endothelial and smooth muscle cells of developing blood vessels. In addition to hemodynamic forces, Piezo1 has been shown to play an inflammatory role, as stiffness-sensing macrophages lacking Piezo1 exhibit reduced inflammation and enhanced wound healing responses. Malfunction of Piezo1 mechanoreceptors has been implicated in abdominal aortic aneurysm (AAA) development. With the increasing evidence of relationship between AAA and IAs, it is important to study Piezo1 dysregulation as a potential cause of IA development and/or rupture.

Methods:
During craniotomy for aneurysm clipping of ruptured and unruptured IAs, we excised and collected the aneurysm dome in four patients. Immunohistochemistry (IHC) was performed for Piezo1 and with CD31 to co-localize Piezo1 in the endothelial cells, and a-SMA to co-localize in smooth muscle cells on all aneurysm domes. Additional specimen was saved for genomic analyses.

Results:
Piezo1 mechanoreceptor overexpression was found in the smooth muscle layer of IAs, but not in superficial temporal artery (STA) controls, in all four human cerebral aneurysm domes. Additionally, there was significant dysregulation of Piezo1 mechanoreceptors in the IA compared with the regular appearance seen in the control human STA (Figure 1). Overexpression was not seen in human arteriovenous malformation specimens.

Conclusions:
Our data is the first demonstration of overexpression of Piezo1 mechanoreceptors in a disorganized manner in the walls of human IAs, which may represent a therapeutic target. We hypothesize that vascular shear stress leads to Piezo1-mediated disorganization in arterial smooth muscle cells and pro-inflammatory activation, which may lead to IA development and rupture.
Abstract TMP17: Polymorphisms In DNA Methylated Genes And Risk Of Intracranial Hemorrhage In Brain Arteriovenous Malformation Patients
Authors: Zaw Thinzar , Weinsheimer Shantel , Nelson Jeffrey , McCulloch Charles , Zaroff Jonathan , Kim Helen
Published: February 2023

Background:
Brain arteriovenous malformations (BAVMs) are a tangle of abnormal vessels that directly shunt blood from the arterial to venous circulation and are a significant cause of intracranial hemorrhage (ICH). DNA methylation, an epigenetic mechanism, can regulate gene expression. Previous studies revealed significant correlations between BAVM development and DNA methylation levels of gene promoter regions in
WTAP
,
METTL3
,
NOS1AP
,
PLA2G7
,
CDKN2A
,
CDKN2B
, and
PDGFD
. Therefore, we investigated whether genetic variants in these candidate genes are associated with risk of ICH at clinical presentation in BAVM patients.

Methods:
A total of 383 single nucleotide polymorphisms (SNPs) were investigated using genome-wide data from 338 BAVM Caucasian patients, mapping within 20kb of the genes:
WTAP
(n=15),
METTL3
(n=12),
NOS1AP
(n=190),
PLA2G7
(n=15),
CDKN2A
/
CDKN2B
(n=22), and
PDGFD
(n=129). We used multivariable logistic regression analysis, adjusting for age, sex, and 3 principal components to adjust for population stratification. The Bonferroni method was used to correct for multiple comparisons (p=0.05/383 SNPs=0.00013). RegulomeDB scores were used to identify putative functional variants.

Results:
Two SNPs were associated with increased risk of ICH with BAVM at nominal p<0.05 but were not statistically significant: rs1263806 in
METTL3
(OR=1.45, p=0.04) and rs1964052 in
NOS1AP
(OR=1.69, p=0.04). Ten SNPs were associated with decreased risk at nominal p<0.05: rs10757261, rs10757261, rs2811711, rs575427 in
CDKN2A
/
CDKN2B
; rs528027, rs260866, rs260842, rs260850, rs7128670, and rs7113370 in
PDGFD
. No SNPs in
WTAP
and
PLA2G7
were associated with ICH (p>0.05). One SNP, rs2811710 mapping to
CDKN2A
/
CDKN2B
(OR=0.6, p=0.02), is predicted to be functionally relevant as an expression quantitative trait loci (eQTL).

Conclusions:
Genetic variants in
WTAP
,
METTL3
,
NOS1AP
,
PLA2G7
,
CDKN2A
,
CDKN2B
, and
PDGFD
are not significantly associated with risk of ICH presentation in patients with BAVM.
Abstract TMP18: Multiplexed Histopathological Characterization Of Cerebral Microbleeds In The Aging Brain
Authors: Srinath Abhinav , Bindal Akash , Moore Thomas , Li Ying , Antonopoulos Mira , Debiasse Dorothy , Zha Yuanyuan , Lightle Rhonda , Pytel Peter , Romanos Sharbel , Polster Sean , Girard Romuald , Awad Issam A
Published: February 2023

Background:
Cerebral microbleeds (CMBs) are manifestations of age-related microangiopathies associated with an increased risk of hemorrhagic stroke and cognitive decline. The pathophysiology of this age-related breakdown of the neurovascular unit remain unclear. Understanding CMB cellular architecture is needed for gene, pathway, and mechanism analyses, to pave the way for biomarker and therapeutic development. Herein, we aim to systematically describe histopathological changes in the CMB lesional milieu.

Methods:
Eight CMBs, along with contralateral non-lesional tissue, were identified by gross appearance at autopsy by a neuropathologist. Samples were first stained with H&E, then Prussian blue for non-heme iron, to localize the lesion. This was followed by multiplex fluorescence staining of β-amyloid and individual cell types including astrocytes (GFAP
+
), macrophages (CD163
+
/Iba1
+
), microglia (CD163
-
/Iba1
+
), B-cells (CD20
+
), T-cells (CD3
+
), and endothelium (CD31
+
). The cell types within the lesional milieu, defined as 200μm from the periphery of the CMB, were quantified using QuPath. Astrocyte and microglia morphology were assessed via fluorescence imaging.

Results:
One CMB contained dilated capillaries, 2 contained lipohyalinized arterioles, and 4 contained dystrophic arterioles due to amyloid angiopathy. Astrocytes and macrophages showed higher normalized cell counts in all CMB tissues compared with controls (
p<0.005
and
p<0.05
, respectively). Astrocytes in 7 of 8 CMB milieux showed reactive morphological changes, including larger cell bodies with peripheral nuclei. Microglia had higher normalized cell counts in 4 CMB tissues, with senescence-associated amoeboid, as well as ramified, reactive morphologies. The lesional milieu also showed higher counts of B-cells in 7 CMB tissues and T-cells in 3 CMB tissues when compared with controls.

Conclusions:
We provide the first description of the cellular architecture of the CMB and the associated lesional milieu. Despite heterogeneity of disrupted vasculature, there are common features of glial reactive changes and inflammation in CMBs. These results offer a basis for additional study of the CMB transcriptome and individual roles of respective cell types in CMB pathology.
Abstract TMP21: Association Of A Perioperative Nausea And Vomiting Treatment Protocol With Reduction In Perioperative Strokes In Children And Young Adults With Moyamoya
Authors: Judge Jennifer , Kappel Ari D , Isibor Christopher , OHara Jill , Larson Anna , Kleinman Monica E , Lehman Laura L , See Alfred P , Smith Edward R
Published: February 2023

Introduction:
Perioperative stroke is a major complication of revascularization surgery in patients with moyamoya. Vomiting is common after neurosurgical procedures and may result in acute changes in intracranial pressure and cerebral blood flow. We instituted a standardized perioperative nausea and vomiting protocol for children and young adults with moyamoya undergoing indirect bypass surgery at our institution.

Hypothesis:
Instituting a standardized perioperative nausea and vomiting protocol will be associated with reduction in the number of perioperative strokes in children with moyamoya undergoing indirect bypass surgery.

Methods:
We retrospectively reviewed consecutive cases of children and young adults with moyamoya who underwent indirect bypass surgery before and after implementation of a new perioperative nausea and vomiting protocol. We compared the rate of strokes in the perioperative period (post-operative day 0 and 1) in the 41 months following implementation (155 surgically treated hemispheres) to 155 surgically treated hemispheres (over 30 months) prior to implementation using Fisher’s Exact test.

Results:
The mean age prior to implementation was 8.7 years (SD 5.5 years) and 9.9 years (SD 6.2 years) post implementation which was not significantly different (p=0.17). In the 30 months prior to initiation of the perioperative nausea and vomiting protocol there were 5 strokes in 155 surgically treated hemispheres (3.2%). After initiation of the protocol, there were no strokes in 155 surgically treated hemispheres (p = 0.03).

Conclusions:
Instituting a standardized perioperative nausea and vomiting protocol was associated with reduction in perioperative strokes in children with moyamoya treated with indirect bypass surgery.
Abstract TMP24: Successful Implementation Of A Pediatric Stroke Alert System At A Non-academic Hospital
Authors: Tilley Jo , Schenk Allyson , Acosta Fernando , Herring Rachelle , Torres Marcela
Published: February 2023

Introduction:
Extensive research exists on the acute treatment of adult strokes, but delayed radiologic diagnosis prevents children from receiving the same interventions. Some academic institutions have implemented pediatric stroke protocols to improve early diagnosis, but without 24/7 in-house pediatric stroke coverage, the protocols are challenging to translate to non-academic hospitals. The goal of this study is to assess the implementation of a pediatric stroke alert protocol at a non-academic institution on time to diagnosis and access to acute treatment.

Methods:
This was an observational study. Pre-stroke alert patients admitted Feb. 19, 2014-Feb. 18, 2019 were retrospectively identified by stroke/TIA ICD-10 codes. Post-stroke alert patients were prospectively identified using our hospital notification system beginning Feb. 19, 2019- July 31, 2022 for ED stroke alerts and Feb. 19, 2020-July 31, 2022 for inpatient stroke alerts. Patients transferred with an existing stroke/TIA were excluded from the study. Non-parametric tests were used for statistical analysis.

Results:
19 ED and 25 inpatient pre-stroke alert patients were identified. Post-stroke alert implementation, stroke/TIA was identified in 20/157 ED stroke alerts (12.74%) and 14/33 inpatient stroke alerts (42.42%). No significant difference was seen in time from ED arrival to diagnosis. However, time last seen well to diagnosis of stroke/TIA was significantly decreased for both ED and inpatient alerts (Table 1), resulting in 3 patients receiving intravenous thrombolysis.

Conclusions:
Although no significant difference was observed in time from ED arrival to diagnosis, implementation of a pediatric stroke alert protocol helped decrease time last seen well to stroke diagnosis. We speculate that increased awareness of pediatric stroke within the community and among medical staff, together with a defined stroke alert process, helped decrease the time of symptom onset to diagnosis.
Abstract TMP25: Major Adverse Brain Events: Incidence Rates Of A Novel Composite Vascular Neurologic Outcome
Authors: de Havenon Adam , Sharma Richa , Sarpong Daniel , Forman Rachel , Prabhakaran Shyam , Spatz Erica S , Krumholz Harlan M , Fernandes Claudia , Roy Brita , Sheth Kevin N , Kernan Walter N
Published: February 2023

Background:
The classical 3-point composite outcome MACE (major adverse cardiovascular events) includes incident stroke, myocardial infarction, and cardiovascular death. Conventional use of MACE may fail to account for important neurological consequences of vascular risk factors. We sought to report incidence rates of a novel composite neurologic outcome called major adverse brain events (MABE), comprised of incident stroke, dementia, and impaired balance in individuals with the vascular risk factor of hypertension.

Methods:
We analyzed TriNetX, the Health and Retirement Study (HRS), and Atherosclerosis Risk in Communities (ARIC), three longitudinal, publicly available datasets. We ascertained MABE as well as MACE and MACABE (MABE & MACE) as comparators by applying distinct adjudication methodologies in each dataset. We also evaluated the effect of good vascular health (maintenance of systolic blood pressure <140mm Hg and moderate or high physical activity, GVH) on rates of MABE and MACE in HRS through odds ratios (OR) adjusted for age, sex, and race/ethnicity.

Results:
We included 10,496,366 hypertensive individuals aged ≥40 years in the TriNetX sample with up to 4 years of follow-up, 2,251 hypertensive individuals aged ≥60 years in HRS with 4 years of follow-up, and 1,409 hypertensive individuals in ARIC with a mean of 4.9 years of follow-up. The incidence of MABE was 10.5% in TriNetX (Figure 1), 35.9% in HRS, and 33.3% in ARIC, of MACE was 17.5%, 40.8% and 12.9%, and of MACABE was 21.2%, 56.3%, and 39.9%, respectively. MABE incidence was highest in older, female, and Black individuals. In HRS, the adjusted OR in those with GVH was 0.50 (95% CI 0.34-0.73) for MABE, 0.71 (95% CI 0.51-0.99) for MACE, and 0.59 (95% CI 0.43-0.82) for MACABE.

Conclusions:
These data suggest that MABE is common among patients with hypertension, even in administrative datasets which are expected to have lower event rates. MABE may be useful for interventions that target brain health.
Abstract TMP26: Effect Of Pioglitazone On Recurrent Stroke Risk In Patients With Post-stroke Cognitive Impairment And Insulin Resistance: Subgroup Analysis Of IRIS Trial
Authors: Schmidt Kat , Power Melinda C , Ciarleglio Adam , Nadareishvili Zurab
Published: February 2023

Patients with post-stroke cognitive impairment are at higher risk of recurrent stroke but the effect of pioglitazone on that risk has not been explored. The goal of this study was to determine the effect of pioglitazone on the risk of recurrent vascular events in patients with post-stroke cognitive impairment (PSCI) and insulin resistance (IR). We studied patients enrolled in Insulin Resistance Intervention after Stroke (IRIS) trial with a baseline Modified Mini-Mental State Examination (3MS) cognitive exam at median of 79 days after their stroke. We considered a baseline score of ≤ 88 on the 3MS to indicate global PSCI, and domain-specific summary scores in the lowest quartile to indicate language, attention, orientation, memory and visuospatial impairments. The primary endpoint of the study was recurrent stroke and MI. We studied n=3,338 patients. In fully adjusted Cox proportional hazards models for recurrent stroke, the hazard ratio (HR) for the effect of pioglitazone compared to placebo differed by post-stroke memory impiarment status (interaction p = 0.01). Pioglitazone was associated with 51% lower risk of recurrent stroke in patients with post-stroke memory impairment [HR = 0.49 (95% CI: 0.30 - 0.81); p = 0.005], but not in those without it [HR = 1.01 (95% CI: 0.75- 1.36); p = 0.942]. In fully adjusted Cox proportional hazards models for MI, the HR for the effect of pioglitazone compared to placebo differed by global PSCI status (interaction p = 0.03). Pioglitazone was associated with 77% lower risk of MI in patients with post-stroke global PSCI [HR = 0.23 (95% CI: 0.08, 0.71); p = 0.01], but not in those without it [HR = 0.88 (95% CI: 0.59, 1.31); p = 0.53]. These data indicate that simple cognitive testing after 3 months from stroke may serve as a precision medicine tool to identify patients at higher risk who may benefit from pioglitazone treatment. This approach can be tested in secondary stroke prevention clinical trials.
Abstract TMP32: Genetic Knockout Of CD38 Is Associated With Improved Cognitive Performance And Protection Against Oxidative Stress In Aged Mice
Authors: Hannawi Yousef , Ewees Mohamed , Zweier Jay L
Published: February 2023

Introduction:
CD38 enzymatic activity is the main determinant of the age-dependent decline in nicotinamide adenine dinucleotide (NAD
+
) levels and the loss of CD38 function has been associated with increased longevity in rodents. Therefore, we hypothesize that the loss of CD38 and its enzymatic function will improve cognitive performance in advanced age through the preservation of NAD
+
levels and the protection against oxidative stress.

Methods:
CD38 Knockout (CD38KO) and C57BL/6J (wild type WT) male mice were aged for at least 24 months. The cognitive performance was compared through Barnes maze, Fear conditioning and Y-maze tests. Dihydroethidium (DHE), Diaminofluorescein-2 diacetate (DAF) and nicotinamide adenine dinucleotide phosphate NAD(P)H staining were used to assess the levels of superoxide, nitric oxide (NO) and NAD(P)H in the brain, respectively.

Results:
5 WT and 5 CD38KO mice aged (24-30) months were included. While there were no significant differences in fear conditioning and Y-maze tests, CD38KO mice showed better memory performance in Barnes maze test including shorter distance travelled (CD38KO: 2±0.06 vs WT: 3.7±1.1 m, p=0.008), longer time in proximity of the holes (CD38KO: 51.2±11.1 vs WT: 34.6±8.4 s, p=0.027), and shorter distance from the hole (CD38KO: 0.17±0.025 vs WT: 0.23±0.04 m, p=0.038) and less errors (CD38KO: 3.5±2.3 vs WKY: 6±0.7, p=0.04). Brain tissue analysis showed 58% lower superoxide (p<0.0001), 129% higher NO (p=0.009), and 141% higher NAD(P)H levels (p<0.0001) in CD38KO compared to WT mice.

Conclusions:
The loss of CD38 and its enzymatic function is associated with better memory performance, less oxidative stress, and higher NAD(P)H in older mice suggesting its potential role as a future therapeutic target against age-related dementias.
Abstract TMP33: Obesity And Hyperinsulinemia Impair Insulin Receptor Transport In The Brain Microvascular Endothelium
Authors: DiLucia Stephanie G , Watson Luke , Williams Alexus , Robinson Catrina
Published: February 2023

Introduction:
Obesity afflicts over 650 million individuals worldwide and is a strong risk factor for both stroke and dementia. Hyperinsulinemia-induced insulin resistance, a finding commonly seen in obesity, is linked to brain insulin deficiency. As insulin is neuroprotective, impaired transport from the peripheral circulation into the brain may underlie the enhanced risk of vascular cognitive impairment in obese individuals. Thus, the focus of this study is to understand the role of aberrant insulin receptor endocytosis in impaired brain insulin transport associated with diet-induced obesity.

Methods:
C57Bl/6J mice were placed on a control or high fat diet beginning at 6 weeks of age for 24 weeks (n=3-5) and hippocampi collected to image microvascular receptor transport. To isolate the effects of insulin resistance, primary murine brain microvascular endothelial cells (MBEC) were exposed to hyperinsulinemia (HI; 20nM insulin for 12 hours). Naïve and HI cells were stimulated for 15 minutes with 20nM insulin and processed for immunoblotting, microscopy, and flow cytometry (n=3-12).

Results:
High fat diet fed mice exhibited reduced internalization of insulin receptor-positive vesicles in the vascular endothelium as compared to controls (0.27+/-0.04 v. 0.37+/-0.02). Correspondingly, HI MBECs displayed reduced insulin receptor internalization, disrupted actin architecture, and a decreased abundance of early endosomes as compared to naïve cells (0.90+/-0.12 v. 2.07+/-0.29). HI cells further demonstrated a shift towards increased endocytic vesicle formation and swelling relative to naïve cells (1.90+/-0.21 v. 1.04+/-0.08), the result of which may be due to an observed increase in endoplasmic reticulum stress and impaired nitric oxide synthase capacity.

Conclusion:
Diet-induced obesity impairs insulin receptor endocytosis into the brain vascular endothelium. These data suggest that hyperinsulinemia induces a compensatory shift in endocytic machinery, with receptors potentially becoming trapped within endocytic buds as opposed to trafficking into the cell. By uncovering the mechanisms linking obesity to cognitive decline, this study will help identify novel therapeutic targets for vascular cognitive impairment and dementia.
Abstract TMP34: Association Of Post-stroke Cognitive Impairment With Long-term Patient-reported Outcome Measures
Authors: Carvalho De Oliveira Lara , Ponciano Ana , Tuozzo Carissa , Viswanathan Anand , Etherton Mark , Rost Natalia S
Published: February 2023

Introduction:
Post-stroke cognitive impairment/dementia (PSCID) is highly prevalent and associated with poor long-term outcomes after acute ischemic stroke (AIS). Recognition of early determinants of PSCID allows for individualized interventions to reduce long-term disability. Furthermore, investigating the relation between PSCID and patient-reported outcomes provides insight into personalized impact of post-stroke cognitive dysfunction. We aimed to identify clinical determinants of PSCID and association with patient-reported outcome measures (PROMs) at 3- and 12-month after AIS.

Methods:
138 AIS patients with no previous history of dementia were included. Clinical variables were acquired on hospital admission. Patients underwent a telephone interview at 3- and 12-months post-stroke including the Telephone Interview for Cognitive Status (TICS), modified Rankin scale (mRS), Barthel Index (BI) and PROM-10 questionnaires. PSCID was defined as TICS < 36 at 12-month post-stroke. Linear regression analyses were performed to identify predictors of 12-month TICS score and association with 3- and 12-month PROMs.

Results:
At 12 months post-stroke, 113 participants (82%) had PSCID. AIS patients with PSCID had higher rates of mRS ≥ 2 at 3-months (61.8% vs. 32%, p = 0.01), worse BI at 12-months (93.12 vs. 102, p < 0.01) and lower 12-month PROMs T Mental scores (48.22 vs. 52.41, p < 0.05). In linear regression analysis, worse functional and patient-reported outcomes at 3- and 12-months were independently associated with lower 12-month TICS
(Table)
.

Conclusions:
Large proportion of AIS patients experience PSCID at 12-months after stroke. 3-month PROMs, especially in the physical domain, are independently associated with worse cognitive measures at 12-months post-stroke. Moreover, PROMs at 12-months after AIS are strongly associated with PSCID. Incorporating PROMs in the ambulatory setting may offer additional insight into cognitive impairment after stroke.
Abstract TMP4: BB-031 Reduces Platelet Reactivity And Attenuates Von Willebrand Factor Levels In A Large Vessel Occlusion Stroke Model
Authors: Mandybur Ian , Wheeler Debra , Zakeri Amanda , Carfora Arianna , Kini Aarushi , Stork Taggart , Anderson Cole , Joseph Matthew , Nimjee Shahid M
Published: February 2023

Introduction:
Acute ischemic strokes (AIS) are a leading cause of death and long-term disability worldwide. Von Willebrand Factor (VWF) is an attractive target for anti-thrombotic therapeutics as it plays a pivotal role in platelet adhesion, activation, and aggregation with large vessel occlusion (LVO) stroke. VWF is stored in an ultra large form in platelet α-granules and Weibel-Palade bodies of endothelial cells from where it is released during injury or inflammation. BB-031 is an RNA aptamer that binds and inhibits VWF, and both prevents and lyses an occlusive thrombus.

Hypothesis:
We hypothesize BB-031 treatment will inhibit VWF thereby reducing platelet reactivity and attenuating the increase in VWF levels in a canine model of LVO stroke.

Methods:
A canine embolic MCAO model was used to assess BB-031 efficacy of VWF inhibition and platelet activity compared to placebo. After 6 hours of LVO with an autologous clot, intravenous treatment was initiated with placebo (n=7), or 0.5 (n=8), 1.0 (n=4), and 5.0 (n=4) mg/kg BB-031. Whole blood was collected at baseline, 6 hours after occlusion then at 10, 15, 20, 25, 30, 60 min after treatment and lastly, at time of sacrifice 9 hours after MCAO induction. Enzyme-linked immunosorbent assay (ELISA) was used to measure circulating VWF and platelet function analysis (PFA-100 Siemens) was utilized to determine platelet reactivity.

Results:
VWF levels immediately after LVO in vehicle control were significantly attenuated within 10 minutes of administration with all BB-031 concentrations (p<0.05). Within 15 minutes after vehicle treatment, VWF levels increased by 3.102 ± .382 ng/ml whereas BB-031 administration of 0.5, 1.0, and 5.0 mg/kg reduced VWF levels by 0.223 ± .154 ng/ml, 0.269 ± .304 ng/ml and 1.053 ± .267 ng/ml respectively. Platelet reactivity to ADP/Collagen (PFA-100) revealed significantly increased platelet closing time in all BB-031 treated canines from immediately after administration through 60 minutes. (p<0.05).

Conclusion:
BB-031 treatment demonstrated significant VWF inhibition and reduced platelet reactivity in a canine AIS LVO model compared to placebo. These findings indicate that BB-031 may offer a superior therapeutic treatment paradigm for ischemic stroke.
Abstract TMP41: Machine Learning-Enabled Automated Large Vessel Occlusion Detection Improves Treatment Times: A Multi-Center Cluster Randomized Clinical Trial
Authors: Martinez-Gutierrez Juan Carlos , Salazar-Marioni Sergio , Abdelkhaleq Rania , Niktabe Arash , Rodriguez-Quintero Juan Carlos , Nahhas Michael , Dhanjani Saagar , Ballekere Anjan , Iyyangar Ananya , Giancardo Luca , Dongarwar Deepa , Sheth Sunil , Kim Youngran
Published: February 2023

Introduction:
Automated LVO detection from CT angiography may improve treatment times in LVO acute ischemic stroke (AIS), as suggested by prior single center non-randomized studies. Here, we perform a cluster randomized trial to evaluate this question with improved rigor.

Methods:
We performed a cluster randomized stepped wedge clinical trial across four comprehensive stroke centers January 2021 to February 2022. An automated LVO detection software (Viz.AI) was implemented at the 4 hospitals in a stepped fashion, with a randomly determined order (Figure 1). We included patients who underwent EVT. Patients presenting within the 2-week software transition period were excluded. The primary outcome was door-to-groin puncture time (DTG) adjusted for age, sex and NIHSS and was determined using a mixed-effect linear regression, with a random effect for cluster (hospital site) and fixed effect for exposure status.

Results:
Among 249 patients that met inclusion criteria, median age was 67 [IQR 57-79], NIHSS 17 [IQR 11-22] and 50.6% were female. Median time from last known well to arrival was 222 minutes and 90% had ASPECTS ≥ 8. A total of 199 patients were treated in the unexposed period and 50 in the exposed. In univariable analysis, median DTG improved in the unexposed vs. exposed periods (91 min [IQR 63 - 108 min] vs. 73 [IQR 32-102 min], p<0.05). In multivariable adjusted mixed-effects model, DTG improved by approximately 15 minutes [4 - 26 min, 95% CI, p<0.01].

Discussion:
In a multi-center cluster randomized trial, implementation of an automated LVO detection algorithm improved treatment times in patients with LVO AIS.
Abstract TMP47: IMPROVING Time To Anti-Coagulation Reversal For Hemorrhagic Strokes
Authors: Dymm Braydon , Kolls Brad , Ehrlich Matthew , Monk Lisa , Shah Shreyansh , Iversen Edwin , Roettig Mayme L , Xian Ying , Jollis James , Granger Christopher , Graffagnino Carmelo ,   IMPROVE Stroke Consortium
Published: February 2023

Background:
Oral anticoagulation (OAC) is a risk factor for intracerebral hemorrhage (ICH) which is an important source of disability and mortality. OAC-associated ICH (OAC-ICH) patients have worse outcomes as compared to ICH patients not on OAC, likely because of the associated larger stroke volumes, higher propensity to intraventricular hemorrhage, and a higher risk of rebleeding. Although current guidelines recommend that OAC should be reversed as quickly as possible, many health care systems have not developed a process for optimizing that aspect of care.

Methods:
Through the IMPROVE Stroke Care Consortium, a group of nine Hub hospitals and their regional community hospitals, a systems of care improvement project was implemented. Performance reviews identified best practices which were disseminated throughout all centers. We compared the median door-to-reversal (DTR) time before and after an institutional campaign to speed the process with a target time of 60 minutes.

Results:
Over two years of the study, there were 6,699 ischemic strokes, 152 subarachnoid hemorrhages, and 889 intracranial hemorrhages. During that time, 36 hemorrhagic stroke patients received reversal agents emergently. The baseline median DTR time was 123 minutes (IQR 99, 361 minutes) for all comers. By the end of the program, the median DTR time had been reduced to 92.5 minutes (IQR 59, 163 minutes) which is a trend towards 59% reduction of DTR from baseline (p=0.08).

Conclusions:
Utilizing an integrated stroke systems of care approach we were able to reduce DTR times for patients presenting with acute ICH and concurrent use of anticoagulants in spite of the lack of definitive guidelines as to how quickly reversing agents should be given.
Abstract TMP48: Current State Of Acute Stroke Thrombolysis In The MT2020+ Caribbean Region
Authors: Gordon Perue Gillian L , Segura Esmeralda , Crandon Domini , Gayle Francene A , Charles Jude , Josephs Nycole , Saint Croix Garly R , Etienne Mill , Mansosalva Herbert , Then Ryna , Inoa Violiza
Published: February 2023

Introduction:
Alteplase is the only FDA approved thrombolytic agent for acute ischemic stroke, tenecteplase is rapidly emerging as an alternative. While both agents are readily available worldwide, low to middle income countries have limited access to acute treatment. To our knowledge, there is no validated tool available to objectively measure access to thrombolytic agents or barriers to routine clinical use.

Methods:
We develop the 17-item tPA Spot Check tool to assess utilization of acute stroke thrombolysis in multiple languages. This tool was used to evaluate the current state of clinical practices in the MT2020+ Caribbean Region. Data was analyzed via SPSS.

Results:
The survey was validated by three international experts with an Average Content Validity Index of 1 and a Universal Agreement index of 1 across three domains: local experience, financial constraints, and barriers to utilization.Survey response rate was 64% (73/114 responses) 46 in English, 14 in Spanish and 13 in French. Fifteen out of 44 MT2020+ Caribbean countries (34%) participated: Haiti, Dominican Republic, Jamaica, Puerto Rico, St. Lucia, Bermuda, Bahamas, Cayman Islands, Trinidad and Tobago, Barbados, Dominica, Venezuela, Nicaragua, Honduras, and Guadalupe. There was limited or no access to thrombolytic agents in 40% of countries surveyed, with 13% resorting to the use of streptokinase. Among cases treated with thrombolytics, 43% of patients had to pay out of pocket before treatment provided, 36% of treatment was paid by insurance plus patients and less than 10% were covered by insurance or governmental support respectively. Among 51% of countries survey, no acute thrombolytic treatment was provided for acute stroke in 2021 calendar year. Only 1 center treated more than 100 cases per year. Majority of respondents (88%) agreed there were barriers to acute stroke thrombolysis in the region. Absence of Stroke protocol (p<0.001), upfront cost of alteplase (p= 0.003) and access to CT scan (p=0.03) were independent predictors of fewer patients treated per year.

Conclusion:
This this survey brings light to an enormous disparity in care of stroke patients around the world, specifically in the MT2020+ Caribbean region. We create a valid tool can be used to assess local access to thrombolytic.
Abstract TMP49: Accuracy Of Toast Subtype Classification In Clinical Practice: Implications For The Get With The Guidelines National Stroke Registry
Authors: Rathburn Cecelia M , Mun Katherine T , Sharma Latisha K , Saver Jeffrey L
Published: February 2023

Background:
TOAST is the most commonly used ischemic stroke subtype classification system worldwide and a required field in the US National GWTG-Stroke registry. However, stroke diagnostics have advanced substantially since TOAST was designed 30 years ago, potentially making it difficult to now apply reliably.

Methods:
We analyzed consecutive ischemic stroke patients admitted to a CSC between July-Oct 2021. Clinical practice TOAST diagnoses rendered by the stroke team in the EMR at discharge were retrieved from GWTG-Stroke registry and compared to a reference (“gold”) standard diagnosis derived from agreement between 2 expert raters after review of the EMR and patient imaging.

Results:
Among 49 patients, age was 72.3y (±12.1), 53% female, and presenting NIHSS median 3 (IQR 1-11). Work-up included: brain imaging in 100%; cardiac rhythm assessment in 100%; cervical/cerebral vessel imaging in 98%; TTE±TEE in 92%; and TCD emboli eval in 51%. Reference standard diagnoses were: LAA-6%, SVD-14%, CE-41%, OTH-8%, UND-more than one cause-18%, and UND-cryptogenic-12%. The Figure shows a bubble plot of congruence between EMR/GWTG-Stroke and reference standard diagnoses. GWTG-Stroke TOAST diagnoses agreed with reference standard diagnoses in 29/49 (59%). Among the 6 subtype diagnoses singly, specificity was generally high (83%-100%), but sensitivity suboptimal for LAA (33%), OTH (75%), UND-MT1 (0%), and UND-CRYPT (17%). Positive predictive value was suboptimal for all: LAA (13%), SVD (58%), CE (77%), OTH (75%), SVD OTH (75%), UND-MT1 (0%), and UND-CRYPT (33%).

Conclusion:
Clinical practice subtype diagnoses using TOAST and entered into GWTG-Stroke were accurate in only 59% of patients, hampering the ability of the national registry to provide dependable insights into subtype-related aspects of care. Development of an updated ischemic stroke subtype classification system, with algorithmic logic directly embedded in electronic medical records, is desirable.
Abstract TMP5: Intravenous Thrombolysis Influence After Successful Mechanical Thrombectomy For Large Vessel Occlusion; Not To Skip Tpa Yet!
Authors: Mohamed Ghada A , Sharf Valerie L , Jacks Kevin , Fugatt Robert , Lee William , Myserlis Evangelos Pavlos , Ali Hamid , Holmstedt Christine A
Published: February 2023

Background:
Despite the high rates of successful reperfusion in the randomized mechanical thrombectomy (MT) trials, only 27% of large vessel occlusion (LVO) patients treated successfully with MT achieved functional independence at 90 days. One proposed theory is impaired distal reperfusion with persistent small thrombi within the microcirculation despite complete recanalization “the no-Reflow phenomenon”. These distal small thrombi would be more suitable to dissolve by thrombolytics.

Methods:
This is a retrospective cohort obtained from Get with the guidelines stroke (GWGS) database available at Medical University of South Carolina Comprehensive Stroke Center (CSC) for LVO patients presented within 4.5 hours of last known well (LNW) between January/2018- June/2022. We aim to investigate the influence of intravenous thrombolysis (IVTPA) on the functional independence mRS (0-2) after a successful MT defined as modified thrombolysis score (mTICI2c-3).

Results:
Of 188 LVO patients who achieved successful reperfusion (TICI2c-3) during the study period, 93 (49%) arrived at our CSC within 4.5 hours of LSW, of them 40 patients (43%) received IVTPA. There was no difference in age, gender, race and initial NIHSS between patients who received IVTPA and those who did not receive IVTPA. Patients received IVTPA arrived at the CSC earlier [median LNW 60 min IQR (51 - 151) vs 165 min (IQR 103- 214), p = <0.001), and had higher ASPECTS score [median 9, IQR (8-10) vs 7, IQR (7-10) p= 0.027]. There was no difference in the collaterals score, clot burden score, site of LVO, tandem nature, door to reperfusion times, post-procedural intracranial hemorrhage or stroke etiology between the two groups. Discharge functional independence mRS (0-2) was achieved more in IVTPA group 65% vs 42% p= 0.025. After adjusting for ASPECTS score, IVTPA patients had higher odds of achieving mRS (0-2) at discharge compared to patients who did not receive IVTPA within 4.5 hours of LNW [aOR 2.42, 95%CI (1.02- 5.75), p= 0.046].

Conclusion:
Intravenous thrombolysis can still influence LVO stroke patients' outcomes with complete revascularization. This positive effect might be related to distal microthrombi thrombolysis and subsequent improvement of the microcirculation flow beyond the occlusion site