bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 106: Chronic Intermittent Hypoxia Induces Neurovascular Dysfunction through Endothelin-1 and Nox2-Derived Radical
Authors: Capone Carmen , Faraco Giuseppe , Coleman Christal , Anrather Joseph , Pickel Virginia , Iadecola Costantino
Published: July 2021

Obstructive sleep apnea (OSA), a condition resulting in chronic intermittent hypoxia (CIH), is an independent risk factor for ischemic stroke, but the mechanisms of the effect are unknown. We hypothesized that CIH increases stroke risk by altering the regulation of cerebral blood flow (CBF) and increasing the brain’s susceptibility to ischemia. Male C57Bl/6 mice (n=5/group) were subjected to CIH (10% O
2
for 90 sec/room air for 90 sec; during sleep hours) for 14 or 35 days (d). Sham-treated mice received room air according to the same schedule. Somatosensory cortex CBF was assessed by laser-Doppler flowmetry in anesthetized mice equipped with a cranial window. CIH increased mean arterial pressure only at 35d (from 74±2 to 83±3 mmHg (p<0.05). However, CIH attenuated the CBF increase produced by neocortical application of the endothelium-dependent vasodilator acetylcholine (sham: 22±1%; CIH:13±1%;p<0.05)

and by whisker stimulation (sham: 23±1%;CIH: 14±1%;p<0.05) both at 14 and 35d. CIH did not alter the CBF increase evoked by adenosine (sham: 23±3%; CIH: 25±1%; p>0.05), indicating that smooth muscle relaxation was not compromised. The effects of CIH were prevented by neocortical application of the endothelin (ET) type A (ET
A
) receptor antagonist BQ123 (1µM;p<0.05) and were associated with ET1 up-regulation in cerebral blood vessels (sham: 52±26;CIH: 5,486±2,466 pg/mg;p<0.05;by ELISA). The angiotensin-II AT1 receptor inhibitor losartan (5µM) did not affect the dysfunction (p>0.05). CIH increased reactive oxygen species (ROS) by 2.3±0.5 folds (p<0.05), assessed by hydroethidine, an effect blocked by the ROS scavenger MnTBAP (100µM; p<0.05) or by BQ123 (p<0.05). Furthermore, the cerebrovascular dysfunction was absent in mice lacking the Nox2-/- subunit of the superoxide-producing enzyme NADPH oxidase and was reversed by neocortical application of a NADPH oxidase peptide inhibitor. The data show that CIH, induces profound alterations of key regulatory mechanisms of cerebral circulation through ET1 and Nox2-dependent ROS production, and raises the possibility that cerebrovascular dysfunction may underlie the increased stroke risk in patients with OSA.
Abstract 108: Cell-Specific Interference with Endothelial PPARγ Produces Oxidative Stress and Accelerates Vascular Aging
Authors: Modrick Mary L , Kinzenbaw Dale A , Ketsawatsomkron Pimonrat , Sigmund Curt D , Faraci Frank M
Published: July 2021

Despite the fact that aging is the greatest risk factor for vascular disease and stroke, relatively little is known regarding mechanisms that promote or protect against vascular aging in experimental models or people. Endothelial dysfunction is a key contributor to both the initiation and progression of vascular disease. Atherosclerosis in carotid arteries (carotid artery disease) greatly increases the risk for ischemic stroke and may contribute to dementia (including Alzheimer’s disease). Peroxisome proliferator activated receptor-γ (PPARγ) is a ligand-activated transcription factor that exerts diverse effects depending on the cell type. Recent work suggests that PPARγ can have beneficial effects in the vasculature including protection against oxidative stress. Relatively little is known regarding the potential role of PPARγ in aging. We used transgenic mice expressing a dominant negative mutation in human PPARγ (V290M) under control of the endothelial-specific vascular cadherin promoter (designated E-V290M) to examine the hypothesis that interference with endothelial PPARγ will promote age-induced vascular dysfunction. Responses of carotid arteries from adult (6±1 mo) and old (23±1 mo) E-V290M mice and non-transgenic littermates (controls) were examined in vitro. Acetylcholine (an endothelium-dependent agonist) produced similar relaxation of arteries from adult control and E-V290M mice as well as old control mice. In contrast, responses to acetylcholine in arteries from old E-V290M mice were markedly impaired. For example, relaxation of the carotid artery to 10 µmol/L acetylcholine was 84±3 and 40±6% in old control versus old E-V290M mice, respectively (P<0.01). The impaired response to acetylcholine in old E-V290M mice could be restored to normal (81±4% relaxation) by tempol, a scavenger of superoxide. Relaxation of the carotid artery to nitroprusside (a nitric oxide donor that acts directly on vascular muscle) was similar in all groups. These findings provide the first evidence that age-related vascular dysfunction is accelerated following cell-specific interference with endothelial PPARγ function. The mechanism that accounts for this change appears to involve reactive oxygen species. Our findings suggest a major protective role for endothelial PPARγ in age-induced oxidative stress and vascular dysfunction.
Abstract 116: Single-synapse Analysis Of Synaptic Remodeling In The Post-stroke Rodent Brain
Authors: Hiu Takeshi , Bliss Tonya M , Olson Andrew , Micheva Kristina D , Tran Kevin , O’Rourke Nancy , Arac Ahmet , Nishiyama Yasuhiro , Smith Stephen J , Steinberg Gary K
Published: July 2021

Introduction:
The mechanisms of functional recovery after stroke are thought to be based on structural and functional changes in brain circuits adjacent to or connected with the stroke site. Deciphering these changes at the synaptic level is key to understanding the re-organization of the synaptic circuitry (i.e. the connectome). Quantitative information about such synapse rearrangements after stroke has been inadequate however, due to the technical limitations of available methodologies. Here we describe the use of array tomography, a new high-resolution proteomic imaging method, to determine the composition of glutamate and GABA synapses in the post-stroke mouse brain.

Methods:
A cortical lesion was induced in 12-week-old C57BL/6J male mice using the distal middle cerebral artery occlusion model of ischemia. Small tissue sections were removed from the peri-infarct cortex and ribbons of serial ultrathin (70 nm) sections were obtained using an ultramicrotome. Ribbons were stained with antibodies for the synaptic markers SynapsinI, VGlut1, VGlut2, PSD-95, GAD, VGAT. Analysis of the resultant staining pattern was used to identify subtypes of glutamatergic and GABAergic synapses.

Results:
At 1 week post-stroke, an increase in GABAergic synapses was observed in layer 5 of the peri-infarct cortex. A sub-analysis of the type of inhibitory interneurons (e.g. parvalbumin, somatostatin) expressing these synapses is pending. In addition, a trend for an increase of VGlut1+2 synapses was also observed. However, there were no detectable differences in total synapse number between stroke-injured and naïve animals, thus suggesting that VGluT2 expression may be upregulated in existing glutamatergic VGluT1 synapses after stroke. Further analysis will be extended to cortical layers 2/3 and 4.

Conclusion:
These results provide new information about the organization of synaptic circuitry and its plasticity after stroke. Furthermore, it demonstrates how array tomography enables a previously unobtainable level of volumetric visualization and quantification of synapses.
Abstract 117: Therapeutic Impact of Direct Cell Sheet Transplantation Derived from Bone Marrow Stromal Cells for Cerebral Infarct in Rats
Authors: Ito Masaki , Kuroda Satoshi , Sugiyama Taku , Kawabori Masahito , Shichinohe Hideo , Miyamoto Michiyuki , Houkin Kiyohiro
Published: July 2021

Background and Purpose
- Less-invasive and efficient donor cell delivery is quite important for the clinical application of cell transplantation therapy. Recently, cell sheet technology has gained a great interest as a novel tissue engineering technology, but there are no studies that evaluate the validity of the bone marrow stromal cell (BMSC) sheets as the donor for cerebral infarct. The aim of this study is to assess whether the BMSC sheet can be an alternative transplantation technique to promote functional recovery after cerebral infarct.

Methods -
The BMSC were harvested from green fluorescence protein (GFP)-transgenic rat and were cultured on a temperature-responsive culture dishes. The mono-layered BMSC sheet was detached by changing the temperature of culture dishes, and was histologically analyzed. Next, the SD rats were subjected to permanent middle cerebral artery occlusion and were divided into 3 experimental groups. Thus, the vehicle or BMSC suspension was stereotactically transplanted into the ipsilateral striatum, or the BMSC sheet was directly transplanted onto the ipsilateral intact neocortex at 7 days after the insult (n=9, 9, 7, respectively). Motor function was assessed for 28 days after transplantation. Finally, histological analysis was performed.

Results -
BMSC sheet was composed of 9.8 ± 2.4 x10
5
cells (n=10). Stereotactic injection of BMSC significantly enhanced the recovery of motor function after cerebral infarct. Likewise, non-invasive cell sheet transplantation also significantly promoted functional recovery. The therapeutic effect was comparable to stereotactic cell transplantation. Fluorescence immunohistochemistry revealed that the GFP-positive cells were densely distributed in the dorsal neocortex adjacent to cerebral infarct in both groups. Double fluorescence immunohistochemistry demonstrated that the majority of engrafted GFP-positive cells were positive for NeuN and morphologically simulated the neurons in both groups. The density of reactive astrocytes in the ipsilateral striatum was less pronounced in cell sheet transplantation group than in stereotactic transplantation group.

Conclusion
- These findings strongly suggest that cell sheet technology would make it possible to non-invasively deliver the BMSC into the infarct brain and to yield significant therapeutic effects, when compared with stereotactic injection of cell suspension. The technology may be a clinically valuable and less-invasive construct for non-invasive and efficient cell delivery to regenerate the infarct brain.
Abstract 128: The Increasing Utilization of Hemicraniectomy for Acute Ischemic Stroke in the United States
Authors: Bhattacharya Pratik , Kansara Amit , Chaturvedi Seemant , Coplin William
Published: July 2021

Background:
The survival outcome of malignant middle cerebral artery infarcts is dismal. In 2007, the pooled analysis from the DECIMAL (Decompressive craniectomy in malignant middle cerebral artery infarcts), DESTINY (Decompressive surgery for the treatment of malignant infarction of the middle cerebral artery) and HAMLET (Hemicraniectomy after middle cerebral artery infarction with life-threatening edema) trials demonstrated a substantial survival benefit from this procedure with a number needed to treat of two for survival. Our objective was to review the nationwide utilization of this potentially life-saving procedure over the last decade.

Methods:
Data from the Nationwide Inpatient Sample for the years 2001 through 2009 were reviewed. Hospitalizations with a discharge diagnosis of an acute ischemic stroke (ICD-9 codes: 433.01, 433.11, 433.21, 433.31, 433.81, 433.91, 424.01, 434.11, 434.91 and 436) were included. Hemicraniectomy utilization was determined using procedure codes 01.2, 01.25 and 02.01 within this subset. Nationwide estimates of utilization were calculated for each year. The Cochrane Armitage test was used to assess trend across the years.

Results:
From 2001 through 2009, there were an estimated 4,917,217 admissions for acute ischemic stroke. Over the 9 years of the study period, the estimated frequency of hemicraniectomy procedures progressively increased from 123 (0.02% of stroke discharges in 2001) to 850 (0.16% of stroke discharges in 2009); trend p<0.0001. The rate of utilization increased largely after 2006. The increase was noted for younger subjects (age < 45 years; trend p<0.0001) and older subjects (age ≥ 45 years; trend p<0.0001). Utilization significantly increased for males and females (trend p<0.0001 for both subgroups). For each year, utilization of hemi-craniectomy was greater amongst males. In contrast with rural and urban nonteaching hospitals, urban teaching hospitals were responsible for the greatest increase in hemicraniectomy utilization: from 0.05% of stroke discharges in 2001 to 0.30% of stroke discharges in 2009.

Conclusion:
The utilization of hemicraniectomy for acute ischemic stroke has increased significantly, coinciding with the publication of compelling results from clinical trials. Early transfer of patients with large middle cerebral artery infarcts to urban teaching centers could potentially extend the survival benefit to a larger population.
Abstract 165: Pial Synangiosis in Patients with Moyamoya less than 2 Years of Age
Authors: Jackson Eric M , Lin Ning , Baird Lissa , Scott R. Michael , Smith Edward R
Published: July 2021

Introduction:
Moyamoya patients under two years of age represent a therapeutic challenge because of their frequent neurologic instability and concomitant anesthetic risks. We report our experience with pial synangiosis revascularization in this population.

Methods:
We reviewed the clinical and radiographic records of all patients with moyamoya syndrome in a consecutive series of patients under 2 years of age, who underwent cerebral revascularization surgery using pial synangiosis at a single institution.

Results:
During a 12-year period (1994-2005), thirty-four procedures (15 bilateral, 4 unilateral) were performed in 19 patients under two years of age (out of a total of 456 procedures in 240 patients). Eighteen of these patients presented with either stroke or TIA. Average age at first surgery was 1.4 years (range 6 months to 1.9 years). Unanticipated staged operations occurred in three patients, two due to persistent EEG changes during the initial surgery and one due to brain swelling during the procedure requiring ventriculostomy. There were two perioperative strokes; both patients had post-operative seizures but made clinical recoveries. The average follow-up was 7 years (range 1-14). In long term follow-up, 13 patients (68%) were clinically independent for their age, with 8 (42%) having no significant deficit. Late complications included subdural hygroma evacuation (1), additional revascularization procedures years later for frontal lobe ischemia (2), late infarction (1) and asymptomatic ischemic change on routine follow-up MRI studies (1). All patients who had both pre and post-operative angiography demonstrated progression of disease.

Conclusions:
Despite the challenges inherent to this population, the majority of children with moyamoya under 2 years of age have a good long-term prognosis. Our data support the use of pial synangiosis as a safe, effective and durable method for treatment of moyamoya for most children in this potentially high-risk population.
Abstract 177: Hemodynamics and Anatomic Evaluation of Intracranial Arteriovenous Malformations Using Phase-Contrast Magnetic Resonance Velocimetry
Authors: Chang Warren , Ciske Benjamin , Loecher Michael , Johnson Kevin , Wu Yijing , Wieben Oliver , Mistretta Charles , Turski Patrick
Published: July 2021

Introduction:
Arteriovenous Malformations (AVMs) have a high lifetime risk of hemorrhage; however treatment carries a significant risk of morbidity/mortality. Wall Shear Stress (WSS) and other hemodynamic parameters are shown to be altered in patients with symptomatic AVMs. Analysis of hemodynamics may have value in stratifying patients into different risk groups to prioritize treatment. We have recently implemented PC-VIPR, a phase contrast MRA technique that can acquire whole brain angiograms with scan time of 5 minutes with velocity data. PC-VIPR has sufficient spatial resolution for both hemodynamic analysis and assessment of anatomic features such as Spetzler-Martin grading.

Materials & Methods:
10 patients with AVMs were scanned using PC-VIPR; WSS and vessel diameter in vessels feeding the AVMs and in normal contralateral vessels were calculated using PC-VIPR velocity data using automated B-spline interpolation. Spetzler-Martin grading was performed by an experienced neuroradiologist.

Results:
Patients with an asymptomatic presentation or mild symptoms (n=4) had no significant difference in WSS between ipsilateral feeding vessels and normal contralateral vessels (1.555 N/m2 vs 1.494, p=0.31), and showed significant vessel dilation in feeding vessels when compared to normal contralateral vessels (4.57 mm vs 3.66, p=0.005) while patients presenting with hemorrhage, severe headaches/seizures, or focal neurologic deficits (n=6) had significantly higher WSS in feeders compared to contralateral vessels (1.607 N/m2 vs 1.146, p=0.003) but the increase in vessel dilation was not statistically significant. (4.34 vs 3.84, p=0.11) Spetzler-Martin grading was performed in all patients and correlated with grading performed via digital subtraction angiography in all cases.

Discussion:
In this study we demonstrate that both hemodynamic analysis and Spetzler-Martin grading can be obtained non-invasively in patients with AVMs using PC-VIPR. Variation in WSS between feeders and normal vessels appeared to relate to the clinical presentation of the patient. Figure 1a shows a WSS map of a patient with mild stable symptoms demonstrating similar WSS in feeders compared to contralateral vessels, Figure 1b shows a WSS map of a patient presenting with hemorrhage with higher WSS in feeders compared to contralateral vessels. Several reports suggest high WSS in AVM feeders stimulates compensatory dilation, normalizing WSS. Hemodynamic analysis using PC-VIPR may have value in risk stratification by identifying patients in which compensation has not yet occurred, with increased risk of hemorrhage.
Abstract 18: Association of Peri-Infarct N-Acetyl Aspartate with Recovery from Stroke
Authors: Sztriha Laszlo K , O'Gorman Ruth , Barker Gareth , Williams Steve , Kalra Lalit
Published: July 2021

Introduction:
Recovery from stroke has been correlated with specific anatomical lesions in the brain, however much of the variability in recovery remains unexplained. Recent research has indicated that the peri-infarct tissue plays a crucial role in recovery. We hypothesised that N-acetyl aspartate (NAA) can serve as a marker of neural integrity in the structurally intact peri-infarct region following stroke, with the potential to predict recovery. The objective of our study was to measure NAA in a longitudinal MR spectroscopy study in stroke patients, and to correlate these findings with functional outcome.

Methods:
Six patients (age 53±10 y) with a non-lacunar ischemic stroke in the left middle cerebral artery territory underwent MR spectroscopy on a 3.0 T MRI scanner. Patients were scanned at 3 and 15 weeks after stroke onset. Proton spectra were acquired from the structurally intact peri-infarct thalamus, the contralesional thalamus, and the anterior cingulate cortex (ACC) using a point resolved spectroscopy sequence with an echo time of 30 ms. NAA concentrations were calculated with LCModel. Clinical assessment included the Fugl-Meyer (FM) scale for the motor performance of the right arm and the NIHSS. Seven healthy controls (age 53±7 y) were also recruited.

Results:
At baseline, NAA was significantly lower in the patients in the structurally intact ipsilesional thalamus (9.0±2.1 vs 11.3±1.2, p=0.030), but not in the other 2 voxels. Baseline NAA was also significantly lower in the ipsilesional thalamus than in the ACC (9.0±2.1 vs 12.7±1.2, p=0.016) in the patients, but not in the controls. NAA decreased significantly between the 2 visits (9.0±2.1 vs 7.2±1.7, p=0.021) in the patients in the ipsilesional thalamus, but not in the other 2 voxels. The patients demonstrated significant clinical improvement during the course of follow up (median 15-point gain on the FM scale, p=0.042; and a 7-point decline on the NIHSS, p=0.026). NAA in the ipsilateral thalamus at baseline significantly correlated with the final FM (r
s
=0.81, p=0.025) and NIHSS scores (r
s
=-0.84, p=0.018).

Conclusions:
Stroke disturbs neuronal integrity in the structurally intact peri-infarct tissue. Despite clinical improvement, neural damage in the peri-infarct area appears to progress during the first 3-4 months following a non-lacunar ischemic stroke. This decreased neuronal integrity is associated with impaired recovery and may therefore represent a therapeutic target. Peri-infarct NAA is a potential biomarker not only for the prediction of recovery, but also for the monitoring of therapeutic interventions.
Abstract 1910: Hyperperfusion in Acute Ischemic Stroke: Serial Arterial Spin-Labeled MRI of Reperfusion and Hemorrhagic Transformation
Authors: Liebeskind David S , Wang Danny J , Sanossian Nerses , Fong Albert K , Hao Qing , Qiao Joe X , Starkman Sidney , Ali Latisha K , Kim Doojin , Raychev Radoslav , Abcede Hermelinda G , Adamczyk Peter , Jahan Reza , Tateshima Satoshi , Gonzalez Nestor R , Duckwiler Gary R , Vinuela Fernando , Saver Jeffrey L , Salamon Noriko , Alger Jeffry R ,   for the UCLA Stroke Investigators
Published: July 2021

Background:
Arterial spin-labeled (ASL) MRI facilitates repeated noninvasive evaluation of cerebral blood flow without the use of contrast. Hyperperfusion may be readily detected with ASL and serial imaging may therefore chronicle the dynamics of territorial perfusion from acute to chronic phases after stroke. We characterized hyperperfusion on ASL in a prospective series of acute ischemic stroke patients, describing the clinical correlates, time course and association with reperfusion hemorrhage.

Methods:
A consecutive series of acute ischemic stroke patients admitted during a 1-year period were evaluated with pseudo-continuous ASL with background suppressed 3D GRASE (delay=2s, matrix=64x64; 26 slices, resolution 3.4x3.4x5mm, scan time 4min). Post-processed ASL CBF maps were visually inspected for detection of hyperperfusion. DSA measures of collaterals and reperfusion were scored when available and hemorrhagic transformation (HT) was graded on GRE in all 198 cases. Univariate and multivariate statistical analyses delineated clinical correlates, timing and other imaging features of hyperperfusion.

Results:
Among 198 patients, mean age was 69.4±15.7 years and 48.5% were women. Among 77 with serial ASL MRI, interval from initial to follow-up MRI was median 25.0 (IQR 10.3-53.9) hours. Hyperperfusion was detected in 15/198 (7.6%) patients at baseline and 30/77 (39.0%) at follow-up. Trajectories included 7/77 (9.1%) with hyperperfusion at both baseline and follow-up and 38/77 (49.4%) showing hyperperfusion at any timepoint during admission. Hyperperfusion correlated with achievement of reperfusion among patients undergoing endovascular therapy (OR 6.5, 95% CI 1.82-23.25, p=0.018) and history of atrial fibrillation (OR 4.4, 95% CI 1.9-10.6, p<0.001). Analysis of the 42 cases with DSA revealed that hyperperfusion was most common in patients with poor collateral grade followed by more complete TICI reperfusion scores. Overall, HT affected 57/198 (28.8%), including 35/198 (17.7%) HI1, 11/198 (5.6%) HI2, 8/198 (4.1%) PH1 and 3/198 (1.5%) PH2. Multivariate analyses revealed that hyperperfusion at any timepoint was a potent predictor of HT (OR 52.6, 95%CI 12.4-222.6, p<0.001).

Conclusions:
Hyperperfusion in acute ischemic stroke is frequently demonstrated by ASL MRI, providing novel insight on the dynamics of reperfusion and HT. Hyperperfusion increases the risk of HT 50-fold, likely due to autoregulatory loss. Poor collaterals and sudden reperfusion in vulnerable cases such as those with atrial fibrillation may herald hyperperfusion and HT.
Abstract 193: IV TPA Administration to Eligible Patients at Certified Primary Stroke Centers
Authors: Alberts Mark J , Hampel MJ , Range Jean , Cantwell Vicki , Troy Joseph , Eggen Nancy
Published: July 2021

Introduction:
The use of IV TPA at Primary Stroke Centers (PSCs) is a key performance metric that can greatly impact patient outcomes after acute ischemic stroke. Concerns remain about whether PSCs administer IV TPA to most eligible patients.

Methods:
We used data from PSCs certified by The Joint Commission (TJC) from 2008 to 2011. Patients who presented within 2 hours of ischemic stroke onset were included if they met a list of eligibility criteria for IV TPA consistent with current guidelines.Results were further analyzed based on several hospital characteristics, including teaching status, urban vs rural setting, and number of certification cycles.

Results:
Data were available from 34,909 patients at 842 hospitals. The overall rate of TPA use in eligible patients was 81% (28269 of 34909 patients). From 2008 to 2011 the rate of TPA use increased from 79.4% to 83.5% (P < 0.0001). The rate of TPA use at teaching hospitals (n=455) was always greater than at non-teaching hospitals (n=367) overall (82% vs 79%, P < 0.001) and each year (80.4% vs 77.6%, 2008; 82.6% vs 80.2%, 2009; 82.3% vs 77.9%, 2010; 84.7% vs 81.4%, 2011; P < 0.005 for all comparisons). The rate of TPA use always increased with the number of certification cycles that a hospital had completed (absolute increase one cycle vs 4 cycles, 20% in 2008; 12.1% 2009; 12.9% 2010; 5.6% 2011; P < 0.004 for all comparisons). The use of TPA was higher at the 783 urban hospitals compared with the 39 rural hospitals (81.3% vs 72.5%, P < 0.001).

Conclusions:
The rate of IV TPA use in eligible patients has increased from 2008 through 2011, and is higher the longer a hospital has been a PSC, and at teaching and urban facilities. Overall PSCs have a high rate of IV TPA administration.
Abstract 201: Changes In Inflammatory Response To Ischemic Stroke Across The Life Span
Authors: Manwani Bharti , Liu Fudong , Sansing Lauren H , Kuchel George , McCullough Louise D
Published: July 2021

Background/Purpose-
Inflammation plays a critical role in the response to stroke, and post-ischemic inflammatory responses strongly contribute to the extent of ischemic brain injury. Although much is known about the post stroke inflammatory cascade in brain; the contribution of age to post ischemic inflammation has been understudied. Aging is a non-modifiable risk factor for stroke and is a critical determinant to stroke outcome. Since 75-89% of strokes occur in the elderly, it is important to characterize the differential effects of aging on the inflammatory response to stroke before translation of immunomodulatory therapeutic strategies into the clinic. Therefore, the objective of this study was
to
study the
impact of
aging
on
post s
troke inflammatory milieu of

the
brain
.

Methods-
Young(6 months), aging(15 months) and aged(22 months) male and female mice were subjected to 60 minutes of MCAO (n=5-6/ group). The ischemic hemisphere was subjected to mechanical and enzymatic digestion and then brain mononuclear cells were harvested at the 30%-60% interphase of percoll gradient. Cells were stained with fluorophore conjugated antibodies for CD45,CD3,CD11b and Gr1 and counted on LSRII cytometer(BD Biosciences).

Results-
Blood derived leukocytes(CD45high) increased in the brain in stroke(7133+−4514) vs. sham(1081+−279.9). We found a significant main effect of age,
F(2,38)=5,p<0.05
and stroke,
F(2,38)=19.5,p<0.01
in the percentage of T cells(CD45highCD3+). There was also a significant age by stroke interaction in the percentage of T cells,
F(2,38)=0.58,p<0.05.
In the CD45intermediateCD11b+ microglia population, we saw a significant main effect of stroke,
F(1,38)=18.6,p<0.01
(sham 19199.2+−3439 vs. stroke 38365.4+−1111
).
Similarly, there was a significant main effect of stroke on CD45intermediate/CD11b+/Gr1+ microglia numbers,
F(1,38)=12.6,p<0.01
.

Conclusions-
T cells, microglia and Gr1+ microglia numbers increase in the brain after an ischemic stroke. However, only the CD45hiCD3+T cells significantly increased in the aging brain after an ischemic insult in the two sexes. Microglia and Gr1+microglia did increase after stroke in both sexes, but there was no significant effect of age. Our study suggests that aging creates a differential inflammatory milieu in the brain after an ischemic event and that elderly mount a profound T cell response to stroke. Since most of our stroke patients are old, bench to clinic translation of stroke therapies needs to account for this heterogeneity in inflammatory response across different ages.
Abstract 2156: Minocycline-induced Attenuation Of Iron Overload And Brain Injury Following Experimental Intracerebral Hemorrhage
Authors: Zhao Fan , Hua Ya , Keep Richard F , Xi Guohua
Published: July 2021

Background and Purpose:
Brain iron overload plays a detrimental role in brain injury after intracerebral hemorrhage (ICH). A recent study found that minocycline acts as an iron chelator and reduces iron-induced neuronal death in vitro. The present study investigated if minocycline reduces iron overload after ICH and iron-induced brain injury in vivo.

Methods:
This study was divided into three parts. (1) Male Sprague-Dawley rats with different sizes of ICH were euthanized 3 days later for serum total iron and brain edema determination. (2) Rats had an ICH treated with minocycline or vehicle. Rats were euthanized 1, 3 and 7 days later for serum iron, brain iron, and brain iron handling protein measurements. (3) Rats had a 50µl intracaudate injection of either saline, FeCl2, FeCl2+minocycline or FeCl2+macrophage/microglia inhibitory factor and were euthanized at one day later for measurements of brain edema, blood-brain barrier disruption and neuronal death.

Results:
After ICH, serum total iron and brain non-heme iron increased and these changes were reduced by minocycline treatment (e.g. serum total iron at day 3: 158±36 vs. 245±22 µg/dL in the vehicle-treated group, p<0.01). Minocycline also reduced ICH-induced upregulation of brain iron handling proteins and neuronal death. Intracaudate injection of iron caused brain edema, blood-brain barrier leakage and brain cell death, all of which were significantly reduced by co-injection with minocycline (p<0.05).

Conclusions:
The current study found that minocycline reduces iron overload after ICH and iron-induced brain injury. It is also well known minocycline is an inhibitor of microglial activation. Minocycline may be very useful for ICH patients because both iron accumulation and microglia activation contribute to brain damage following ICH.
Abstract 2197: Telestroke: Optimizing Access to Emergency Interventions in Acute Stroke Care
Authors: Johnson Rayetta
Published: July 2021

Background and Issues:
The burden of stroke in North Carolina is one of the highest in the nation (approximately 28,000 stroke hospitalizations from 2003-2007). The number and high costs of stroke have made it incumbent to improve the numbers of patients receiving effective treatment. There are two major barriers for treatment of acute stroke: time and access. The utilization of telestroke in community hospitals aids in decreasing these barriers by providing immediate access to a stroke neurologist. In order for telestroke to be successful, awareness and education regarding acute stroke care must be provided for health care providers as well as the communities. Thus, the development of a telestroke system requires nursing and medical expertise. The Primary Stroke Center Team at Wake Forest Baptist Medical Center in Winston-Salem, N.C. implemented a telestroke network system (Intouch's Health's RP-7 Robotic system) in January of 2010 to provide 24/7 access to the medical center's acute stroke experts and the latest advancements in stroke interventions. There are eight hospitals in the network at the present time.

Methods:
Our team identified that many of the network hospital's staff are not experienced in taking care of a stroke patient and that a “roadmap” is useful to guide them in these steps.The stroke nurse specialist developed a quality improvement plan for the network hospitals which included: an evidence-based algorithm for patient care; stroke education, in particular, neurological assessment and tPA administration classes for the ED staff; quarterly meetings to provide outcome and feedback data with each network hospital; stroke awareness events for the community. Mock telestroke consults were also performed prior to “going live” with telestroke for each of the network hospitals. Of utmost importance is the early involvement and education of the EMS system in the respective county of the network hospital. The buy-in of EMS was found to be a key component in the success of the network. Finally, attention to customized quality improvement efforts for each of the facilities are required to accomplish integration into the telestroke network.

Results:
The data has been analyzed, and thus far, a 24% rate of tPA administration has been seen with our network hospitals (an increase from the 3.6% national average). Comparisons between each of the eight network hospitals' rates of administration of tPA prior to and after joining the network show a trend of increase (10%-40%). The effectiveness of the algorithm has also been explored by analysis of feedback and initial results have shown a positive impact.

Conclusion:
A combination of improving access to stroke neurologists in conjunction with a focus on improving the level of care via evidenced based stroke care teaching and implementation of algorithms at a network hospital is required for implementing and building a successful telestroke network.
Abstract 2206: Trends in Mortality of Acute Ischemic Stroke after Hospital Discharge
Authors: McKinney James S , Deng Yingzi , Paolucci Ugo , Kostis John B
Published: July 2021

Introduction---
Advances in emergent treatment and hospital management of acute ischemic stroke (AIS) have decreased in-hospital mortality. Despite this early reduction in mortality, prior research has indicated that up to 25% of patients hospitalized for AIS will be dead one year after admission. We assessed the trends in prognosis for patients hospitalized for AIS.

Methods---
We used the Myocardial Infarction Data Acquisition System (MIDAS) database, which includes demographic and clinical data on patients discharged with a primary diagnosis of cerebral infarction from all non-federal acute care hospitals in New Jersey between 1996 and 2007. Out-of-hospital deaths were assessed by matching MIDAS records with New Jersey death registration files. In-hospital, 1-year, and interval (discharge to 1-year) mortality were calculated. Total, cardiovascular disease (CVD), and non-CVD mortality were calculated. Log linear regression models were used for trend analysis. Multivariate logistic and Cox regression models were used to measure the effect of year of admission on in-hospital and 1-year mortality, respectively, after adjusting for demographics, comorbid conditions, and treatment. Statistical significance was defined as a
P
-value ≤ 0.05.

Results---
134,441 patients were admitted with a primary diagnosis of cerebral infarction during the study period. Significant declines were observed for in-hospital (10.4% to 8.1%, p<0.05) and 1-year (26.0% to 24.0%, p<0.05) mortality. No significant changes were observed in the interval death rate between hospital discharge and 1-year. Significant declines for in-hospital (7.4% to 5.5%, p<0.05) and 1-year (16.9% to 12.8%, p<0.05) CVD mortality were also observed (
Figure
, Panel A). Trends in interval CVD showed significant declines after 2003, while interval non-CVD death rates steadily increased (
Figure
, Panel B). Multivariate logistic analysis confirmed the declining likelihood of death from CVD versus non-CVD during the study period (OR = 0.954; 95% CI = 0.946 to 0.962).

Conclusion---
Stroke patients admitted to New Jersey hospitals had a significant decline in in-hospital and 1-year mortality over the study period. This reduction was primarily driven by reductions in CVD death. Despite this trend no change was observed in interval mortality due to a 25% increase in non-CVD deaths.
Abstract 2211: Statin Therapy May Increase the Risk of Intracerebral Hemorrhage: A Meta-analysis of 26 Randomized Controlled Trials
Authors: McKinney James S , Kostis William J , Kostis John B
Published: July 2021

Introduction---
Statin therapy decreases the risk of myocardial infarction and ischemic stroke. However, an increased risk of intracerebral hemorrhage (ICH) has been observed in some studies. To investigate this issue we performed a meta-analysis of all randomized controlled trials (RCTs) using statins that reported ICH.

Methods---
We performed a Medline literature search through March 18, 2011 and identified additional RCTs by reviewing reference lists of retrieved studies and prior meta-analyses. All RCTs of statin therapy versus placebo or high dose versus low dose statin therapy that reported ICH or hemorrhagic stroke were included. The primary outcome variable was ICH. 26 RCTs were included. All analyses used random effects models and heterogeneity was not observed in any of the analyses.

Results---
84 831 subjects were included in the Active group, and 84 851 in the Control group. A trend towards a higher incidence of ICH was observed in the Active treatment group compared to Control (OR = 1.15; 95% CI = 0.91 to 1.45,
p
=0.24) (Figure). Significant relationships were not observed between the log OR for ICH with achieved LDL in the Active group (slope = 0.0002; 95% CI = -0.0098 to 0.0101,
p
=0.96) or with the difference in LDL drop between the Active and Control groups (slope = 0.0030; 95% CI = -0.0089 to 0.0149,
p
=0.62). Total stroke (OR = 0.84; 95% CI = 0.78 to 0.91,
p
<0.001) and all-cause mortality (OR = 0.91; 95% CI = 0.86 to 0.96,
p
<0.001) were significantly reduced in the Active group. A significant relationship between all-cause mortality and the difference in LDL drop between the Active and Control groups was observed (slope = -0.0030; 95% CI = -0.0009 to -0.0051, p<0.005). There was not evidence of publication bias in this meta-analysis.

Conclusions---
Active therapy was associated with a trend towards increased ICH in this meta-analysis of 26 RCTs of statin therapy. However, this risk does not appear to be related to the degree of decline or achieved LDL. The risk of ICH is offset by a significant reduction in ischemic stroke and all-cause mortality and should not dissuade practitioners from prescribing statins in otherwise appropriate patients.
Abstract 2212: Vitamin D Intake: A Novel Neuroprotectant?
Authors: Judd Suzanne E , Le Anh , Kleindorfer Dawn O , Kissela Brett , Muntner Paul , Gutierrez Orlando , Unverzagt Fred , Wadley Virginia
Published: July 2021

Introduction
Vitamin D is both a nutrient and hormone and has become increasingly studied as it relates to circulatory and neurological functioning. Vitamin D deficiency has been associated with Parkinson's disease, Alzheimer's disease, stroke, and dementia. It has also been related to hypertension and diabetes. We examined the role of vitamin D intake on incident stroke and incident cognitive impairment in a cohort of middle aged and older adults.

Methods
The Reasons for Geographic And Racial Differences in Stroke (REGARDS), a cohort of 30,239 participants, was recruited between 2003 and 2007 and is comprised of black and white Americans age 45 and older at baseline. Vitamin D intake was measured by the Block 98 food frequency questionnaire and categorized into tertiles. Participants are surveyed every six months for incident strokes which are adjudicated using medical record review. Cognitive functioning is assessed annually using the Six-item Screener (SIS)(score range 0-6). A score of 4 or below indicates impairment. For the incident stroke analysis, we excluded all people with prior history of stroke, and for the incident cognitive impairment analysis we excluded those with SIS scores<5 at baseline.

Results:
26,039 participants were available for this analysis and were followed over a mean of 5 years. Higher intake of vitamin D was more likely for whites but did not differ by gender or age. Compared to the lowest tertile (range: 0-53.1 IU/day vitamin D), the highest tertile (range: 382-1774 IU/day) of vitamin D intake was associated with a 11% reduction in stroke (HR=0.89; 95% CI =0.79, 1.01) and 24% reduction in cognitive impairment (HR=0.76; 95% CI =0.67,0.86) after adjustment for age, race, income, education, hypertension, diabetes, dyslipidemia, history of heart disease, and BMI. When stratifying by race results were similar for both stroke and cognitive decline. Adding dairy intake to the models slightly attenuated the association but did not meaningfully change the interpretation of the results.

Discussion:
Results suggest a potential role of vitamin D in incident stroke and cognitive impairment. Clinical trials could evaluate the potential of Vitamin D as a neuroprotectant.
Abstract 2244: Synergistic Benefit Of Combined Amlodipine Plus Atorvastatin On Neuronal Damage After Stroke In Zucker Metabolic Rat
Authors: Kawai Hriromi , Deguchi Shoko , Deguchi Kentaro , Yamashita Toru , Ohta Yasuyuki , Omote Yoshio , Kurata Tomoko , Ikeda Yoshio , Matsuura Tohru , Abe Koji
Published: July 2021

Stroke is a major neurologic disorder and a leading cause of death in the world. We compared neuroprotective effects of single or combination therapy of amlodipine (AM) and atorvastatin (AT) in such a metabolic syndrome model Zucker rat after 90min of transient middle cerebral artery occlusion (tMCAO). The animals were pretreated with vehicle, AM, AT, or the combination of AM plus AT for 28 days, and at 24 h of tMCAO, infarct volume and immunohistochemical analyses were performed. The combination of AM plus AT treatment decreased the infarct volume stronger than each single treatment withAMor AT. The numbers of positive cells of oxidative stress markers such as 8-hydroxy-2′-deoxyguanosin (8-OHdG), 4-hydroxy-2-nonenal (4-HNE), and advanced end glycation products (AGE) and inflammation markers such as tumor necrosis factor alpha (TNF-α) and monocyte chemoattractant protein-1 (MCP-1) decreased dramatically in the combination-treated group compared with single AM or AT-treated group. The present study showed that single AM or AT treatment showed neuroprotective effects both with antioxidative and anti-inflammatory mechanisms, but combination therapy of AM plus AT presented a further synergistic benefit in acute ischemic neural damages. Moreover, the single treatment with AM or AT itself exerted neuroprotective effects with reducing inductions of MMP-9 and AT2R, as well as with preserving collagen IV, and the combination therapy of AM plus AT showed a further synergistic benefit against acute ischemic neural damages. Single AT was more protective on these 3 molecules than single AM at this time point of 24 h after tMCAO. Thus, the combination therapy with AM plus AT extended the neuroprotectives effect of single treatment with AM or AT on a part of neurovascular unit and a hypertension related receptor.
Abstract 2330: Citicoline Is A Strong Pro-angiogenic Molecule And Protects Brain Endothelial Cells From Apoptosis After Stroke
Authors: Slevin Mark , Grau-Olivares Marta , Matou.Nasri Sabine , Rovira Norma , Justicia Carles , Planas Anna , Li DH , Secades Julio J , Krupinski Jerzy
Published: July 2021

Background and purposes
- Citicoline is neuroprotective agent used in stroke patients. Citicoline induces angiogenesis i
n vitro
; however, the molecular mechanisms induced by citicoline have not been fully investigated. The present study was designed to investigate the key signalling mechanisms through which citicoline modulates angiogenesis-associated with stroke recovery.

Methods
-
In vitro
angiogenesis assays: migration (Bodyen chamber, a chemotaxis assay and wound recovery), proliferation and differentiation into tube-like structures in Matrigel
TM
as well as spheroid development assays were carried out using human brain microvessel endothelial cells (HBMECs). Western blotting was performed on the protein extraction from HBMEC stimulated with citicoline. Citicoline signalling pathway was studied using a phospho-protein screening array performed by Kinexus. A Staurosporin/calcium ionophore-induced apoptosis assay was performed by seeding HBMEC on the glass coverslips. Cells were pre-incubated with citicoline and the apoptosis was induced by addition of the ionophore or staurosporin. Cells were examined by microscoy and/or stained using propidium iodide and Hoechst stain solution and then counted under fluorescence microscope. Transient MCAO was carried out on Sprague Dawley rats (n=4 per group) with and without citicoline treatment (1000mg/Kg) applied at the time of occlusion and subsequently every 3 days until euthanasia (21 days). Vascularity of the stroke-affected regions was examined with antibodies recognising the microvessels (CD34) and active cells (CD105).

Results
- Citicoline presented no mitogenic and chemotactic effects on HBMEC; however, it significantly increased wound recovery, the formation of tube-like structures in Matrigel
TM
-with a stronger effect than FGF-2, and enhanced spheroid development and sprouting. Citicoline induced the expression of ERK-1/2, known to be involved in last step of signalling pathways of angiogenesis. Kinexus results showed an over-expression of ASK-1, HER2, IRS-1 and Jun and inhibition of Hsp27, Integrin alpha4, MEK1 (MAP2K1) and Histone H2B proteins. Knock-down of IRS-1 with targeted siRNA inhibited the pro-angiogenic effects (sprouting and tube-formation) of citicoline in HBMECs. The percentage of surviving cells was higher in the presence of citicoline after inducing apoptosis. Histology of infarcted regions showed that citicoline significantly increased the numbers of new active (CD105-positive) microvessels.

Conclusion
- The findings demonstrate both a pro-angiogenic and protective effect of citicoline on HBMECs in vitro and following MCAO in vitro. Additionally, this molecule may play a key role in the modulation of angiogenesis thereby and ultimately, improving tissue function, revascularisation and neuronal survival after ischaemic stroke.
Abstract 2357: Src Kinase Inhibition Blocks Thrombin-induced Brain Injuries without Cognitive Side Effects
Authors: Liu Da-Zhi , Ander Bradley P , Izadi Ali , Van Ken , Zhan Xinhua , Tian Yingfang , Stamova Boryana , Jickling Glen , Berman Robert F , Lyeth Bruce G , Sharp Frank R
Published: July 2021

Intracerebral hemorrhage (ICH) activates thrombin, a potent mitogen. Thrombin triggers mitosis by modulating several intracellular mitogenic molecules including Src family kinases. These molecules regulate mitogen-activated protein kinases (MAPKs) and cell cycle proteins such as cyclin-dependent kinases (Cdks); and play critical roles in mitogenic signaling pathways and cell cycle progression. Since aberrant cell cycle reentry results in death of mature neurons, cell cycle inhibition appears to be a candidate strategy for the treatment of neurological diseases including ICH. However, this can also block cell cycle (proliferation) of neural progenitor cells (NPCs) and thus impair brain neurogenesis leading to cognitive deficits. We hypothesized that inhibition of cell cycle by blocking mitogenic signaling molecules (i.e., Src family kinase members) blocks cell cycle reentry of mature neurons without injuring NPCs, which will avoid cognitive side effects during cell cycle inhibition treatment for ICH. Our data shows: (1) Thrombin 30U/ml results in apoptosis of mature neurons via neuronal cell cycle reentry
in vitro
; (2) PP2 (Src family kinase inhibitor) 0.3 µM attenuates the thrombin-induced neuronal apoptosis via blocking neuronal cell cycle reentry, but does not affect the viability of NPCs at the same doses
in vitro
; (3) Intracerebral ventricular thrombin injection (20U, i.c.v.) results in neuron loss in hippocampus and cognitive deficits 5 weeks after thrombin injection
in vivo
; (4) PP2 (1mg/kg, i.p.), given immediately after thrombin injection (i.c.v.), blocks the thrombin-induced neuron loss in hippocampus and cognitive deficits, whereas PP2 on its own at the same doses does not affect normal cognition
in vivo
. These suggest that Src kinase inhibition prevents hippocampal neuron death via blocking neuronal cell cycle reentry after ICH, but does not affect survival of NPCs.