bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 419: OLA1 Regulates GSK3β/eIF2-alpha Signaling Axis in Angiotensin II-treated Human Ventricular Cardiomyocytes
Authors: Jeyebal Prince , Shi Zheng-Zheng , Krishnamurthy Prasanna
Published: March 2022

Pathological cardiac hypertrophy in response to stress or disease such as hypertension, myocardial infarction, valvular disease or neurohomonal dysregulation often result in heart failure. Cardiac hypertrophy is associated with changes in key molecular features including protein synthesis, sarcomeric organization, fibrogenesis, cell death and energy metabolism. OBG like ATPase 1 (OLA1) belongs to the translation factor-related (TRAFAC) class, Obg family, and YchF subfamily of P-loop GTPases that play a crucial role in the regulation of diverse cellular processes including protein translation, intracellular transport, signal transduction and growth. Recent study has shown that OLA1 functions as an intrinsic regulator in cellular stress responses, such as oxidative stress and heat shock. However, its role in cardiac hypertrophy is unknown so far. Here, we investigated the effect of OLA1 deficiency on angiotensin II (ANG II)-induced hypertrophic signaling response in immortalized human ventricular cardiomyocytes (hCM) and in heart tissue from OLA1 knockout mice. We observed that ANG II-induced increase in cardiomyocyte cell size was lower in OLA1 knockdown hCM cells as compared to control transfected cells. Interestingly, OLA1 knockdown inhibits the above effect and increases phosphorylation of GSK3β and eIF2α (inactive state). Furthermore, OLA1 homozygous knockout mice showed increase in phosphorylation of GSK3β. Taken together, these findings show that OLA1 deficiency decreases ANG II-induced hypertrophy signaling response in ventricular cardiomyocytes. This study provides the first evidence for the role of OLA1 in ANG II-induced hypertrophic response of human ventricular cardiomyocytes.
Abstract 457: Rad-deletion Provides Dual Therapeutic Benefits for the Heart
Authors: Manning Janet R , Chelvarajan Lakshman , Withers Catherine N , Nagareddy Prabhakara R , Haggerty Christopher M , Fornwalt Brandon K , Tripathi Himi , Abdel-Latif Ahmed , Andres Douglas A , Satin Jonathan
Published: March 2022

Rationale:
Myocardial infarction (MI) compromises the overall mechanical function of the heart, reducing cardiac output and triggering decompensatory remodeling. Rad GTPase is an L-type calcium channel complex (LTCC) constituent that governs trigger calcium in the myocardium. Rad deletion in mice results in increased Ca
2+
handling and a sustained non-pathological improvement in left ventricular function compared to wildtype.

Hypothesis:
Rad-ablation attenuates post-ischemic loss of function, resulting in reduced remodeling and improved long-term contractility.

Methods and Results:
We subjected Rad-deficient (Rad
-/-
) mice to ligation of the left anterior descending (LAD) coronary artery, and monitored cardiac structure and function using echocardiography and single cell Ca
2+
measurements. We found that Rad deletion reduces both mortality and contractile dysfunction after MI, as well as ventricular dilation over five weeks. This improvement is also accompanied by preserved Ca
2+
handling in isolated myocytes. Histological and MRI examination of
ex vivo
global ischemia and
in vivo
24 hour post-MI myocardium revealed that initial infarct size and area at risk are comparable between knockout and wildtype. Rad loss reduced scar spread independent of preserving tissue viability. mRNA microarray findings implicated differential inflammatory pathway activation with Rad-deletion. Rad
-/-
showed reduced neutrophil extravasation and reduced inflammatory cytokines in the left ventricle 24 hours after MI.

Conclusion:
Rad deletion results in reduced cardiac remodeling, diminished myocardial inflammation, and improved contractile function before and after MI. These results suggest that Rad-deletion is a novel therapeutic direction that may serve as a combined positive inotrope and regulator of acute MI inflammatory response.
Abstract 477: Nuclear Receptor Nur77 Modulates Cardiac Function via Neuropeptide Y and Neuropeptide Y Receptor 1 Signalling
Authors: Medzikovic Lejla , van Roomen Cindy P , Baartscheer Antonius , Creemers Esther E , Remme Carol Ann , Arkenbout Karin , de Vries Carlie J , de Waard Vivian
Published: March 2022

Cardiac function is modulated by the sympathetic nervous system via catecholamines released from cardiac sympathetic nerve endings and adrenal chromaffin cells. The co-transmitter Neuropeptide Y (NPY) is co-released with catecholamines and also modulates cardiac function. NPY has previously been reported as an independent predictor of mortality in heart failure patients. In experimental models, NPY induces cardiac hypertrophy and elevates cardiomyocyte intracellular Ca
2+
concentrations and Ca
2+
-dependent signalling. However, not much is known yet about the upstream regulation of NPY in the context of cardiac function modulation.

Interestingly, a robust upregulation of NPY gene expression has been reported in macrophages lacking the nuclear receptor Nur77. We have shown that Nur77 deficiency in mice leads to alterations in cardiomyocyte Ca
2+
homeostasis and adverse cardiac remodelling in response to isoproterenol. As these effects may be explained by enhanced NPY action in Nur77-deficient (Nur77-KO) mice, we hypothesized that Nur77 is a regulator of NPY.

We now show that Nur77 down-regulates NPY expression in and secretion from sympathetic cells
in vitro
. Furthermore, NPY levels are significantly higher in blood plasma and hearts from Nur77-KO compared to wildtype mice. Antagonism of NPY receptor 1 (NPY1R) attenuates cardiac hypertrophy and elevated cardiomyocyte Ca
2+
responses caused by Nur77 deficiency. Interestingly, cardiomyocyte-specific Nur77-deficient mice also exhibit elevated cardiomyocyte Ca
2+
levels, which is partially reduced by NPY1R antagonism, even though plasma and cardiac NPY levels are similar to control mice.

In conclusion, the transcription factor Nur77 regulates cardiac function both via systemic mechanisms and in cardiomyocytes intrinsically, via NPY/NPY1R modulation. These results imply a novel role for Nur77 as a potential modifier gene in heart failure.
Abstract 481: GRK5 as a Novel DNA-Binding Protein in Cardiomyocyte Hypertrophic Stress
Authors: Coleman Ryan
Published: March 2022

Introduction:
The pathogenesis and progression of heart failure (HF) encompasses aberrations in gene regulation, leading to ventricular remodeling and maladaptive cardiac hypertrophy. A common maladaptation in HF is an increase in the expression level of the G protein-coupled receptor kinase, GRK5. Recently, non-canonical roles for GRK5 have been uncovered that are crucial for the development of maladaptive hypertrophy and these are due to nuclear translocation and accumulation of GRK5. We have shown that GRK5 is a histone deacetylase kinase promoting de-repression of hypertrophic gene transcription through MEF2 and can also facilitate transcriptional activity of NFAT through DNA-binding. The latter is consistent with studies revealing that GRK5 contains a DNA-binding domain.

Hypothesis:
We hypothesize that the DNA-dependent roles of GRK5 are a mechanism by which GRK5 contributes to gene reprogramming in myocardial hypertrophic stress.

Methods:
To further study this, neonatal rat ventricular cardiomyocytes overexpressing GRK5 were subjected to α-adrenergic stress with 50μM phenylephrine (PE) or vehicle for 30 minutes to induce nuclear accumulation of GRK5. Chromatin was isolated and GRK5 immunoprecipitation (ChIP) employed to pull-down DNA associated with GRK5 (n=3 PE, n=4 vehicle). Next generation sequencing of this DNA provides an unbiased view of GRK5 DNA binding.

Results:
The GRK5 ChIP-Seq revealed that GRK5 translocation upon hypertrophic stress leads to multiple promoter, exon, and enhancer DNA-binding events. Gene ontology revealed enrichment of pathways known to be involved in hypertrophy, including the NFAT and Ras pathways. Promoters for genes relevant to cardiac hypertrophy, such as bone natriuretic peptide and early growth response 1 were also found to be enriched by GRK5 immunoprecipitation with PE treatment. In conclusion, we show that during hypertrophic stress, GRK5 mobilizes to the nucleus of myocytes and localizes around diverse genes involved in cardiomyocyte hypertrophy. Further studies
in vivo
will reveal whether GRK5 has a causal DNA-dependent role in gene reprogramming in HF.
Abstract 5: Restoring Nitroso-Redox Balance as a Therapeutic Approach for Cardiovascular Disease
Authors: Shettigar Vikram , Wang Honglan , Zhang Bo , Roof Steve R , Janssen Paul M , Davis Jonathan P , Gumina Richard J , Biesiadecki Brandon J , Villamena Frederick A , Ziolo Mark T
Published: March 2022

Anti-oxidant therapy has been an immense clinical disappointment for the treatment of cardiomyopathies. Concurrently with the increase in reactive oxygen species (ROS), there is also a decrease in cardiac levels of nitric oxide (NO), resulting in a nitroso-redox imbalance not addressed by anti-oxidant treatment alone. Key modulators of cardiac function are sensitive to the nitroso-redox balance such as kinases and phosphatases. Thus, along with changes in protein oxidation and/or S-nitrosylation levels, the nitroso-redox imbalance also alters protein phosphorylation. We developed a unique and novel compound (EMEPO) that can correct the nitroso-redox imbalance by simultaneously scavenging ROS and producing NO. We hypothesized that EMEPO is a novel agent that will ameliorate cardiac dysfunction by reestablishing the proper protein post-translational modifications. We demonstrated the efficacy of EMEPO in two cardiac models of nitroso-redox imbalance; a genetic model (NOS1
-/-
) and a disease model- murine myocardial infraction (MI). Both models displayed nitroso-redox imbalance with systolic and diastolic dysfunction. EMEPO treatment had a much greater effect than anti-oxidant treatment alone in palliating the cardiac dysfunction. A major contributor to these dysfunctions observed in cardiomyopathies is altered ryanodine receptor (RyR) activity. EMEPO was able to restore RyR activity and each aberrant post-translational modification (oxidation, S-nitrosylation, and phosphorylation). We believe these EMEPO-induced changes in RyR will occur in many proteins that orchestrate signaling networks and function. Our data highly suggest that simultaneously restoring both ROS and NO levels (i.e., correcting the nitroso-redox imbalance) is a promising therapeutic approach for MI and heart failure patients. Our first designed nitroso-redox balancer, EMEPO, shows great potential as a novel strategy for the treatment of heart disease.
Abstract 52: CagA-Positive Exosomes From Patients With Helicobacter Pylori Infection Impair Endothelial Function in Association With Increased Gata-3 Expression
Authors: Xia Xiujuan , Zhang Linfang , Hu Tingzi , Chi Jingshu , Xu Canxia , LIU Zhenguo
Published: March 2022

A significant link between atherosclerosis and associated cardiovascular diseases especially coronary artery diseases (CAD) and infection with H. pylori (especially CagA-positive) has been established clinically. However, how H. pylori infection leads to atherosclerosis and CAD is unclear. It is well known that endothelial injury and dysfunction plays a critical role in the development of atherosclerosis and CAD. The present study was designed to determine if the effect of cytotoxin associated gene A (CagA) on vascular endothelial cells and related mechanisms. Exosomes were prepared from patients with CagA-positive H. pylori infection and CagA-negative H. pylori infection, and analyzed with electronic microscope and nanoparticle tracking analysis. The presence or absence of CagA in the exosomes from patients was confirmed using Western blot. The exosome preparations were then incubated with human umbilical endothelial cells (HUVEC) for 24 hours. PBS and exosomes from patients without H. pylori infection were used as controls. It was found that the CagA-positive exosomes, not CagA-negative exosomes, significantly inhibited the proliferation of HUVECs and VEGF production in a dose-dependent manner. Incubation with the CagA-positive exosomes, not CagA-negative exosomes, also significantly increased the production of the inflammatory factor CHI3L1 from HUVECs associated with increased expression of GATA-3. The data from the present study demonstrated that CagA-positive exosomes, not CagA-negative exosomes, from patients with H. pylori infection significantly impaired endothelial function in association with increased expression of GATA-3. Further studies are needed to investigate the mechanisms for the action of CagA-positive exosomes on endothelial cells.
Abstract 54: The Effect of Nicotine and Menthol in Secondhand Smoke on Endothelial Function
Authors: Liu* Jiangtao , Nabavizadeh* Pooneh , Derakhshandeh Ronak , Wang Xiaoyin , Glantz Stanton A , Springer Matthew L
Published: March 2022

Introduction:
We have previously shown that even one minute of exposure to secondhand smoke (SHS) of tobacco and marijuana can impair arterial flow-mediated dilation (FMD) in rats. The identity of specific constituents of SHS that cause vascular toxicity remains unclear. Nicotine is a vasoconstrictor that potentially can affect vascular function. Menthol is a cigarette additive popular with African Americans, women, youth, and other ethnicities. Menthol interacts with smoke constituents and irritants such as acrolein through receptor ion channels and also affects the metabolism rate of nicotine.

Hypothesis:
We tested three hypotheses pertaining to acute effects of brief exposures to SHS: (1) nicotine increases the extent of endothelial functional impairment; (2) menthol decreases the extent of endothelial functional impairment; and (3) there is an interaction between the effects of nicotine and menthol.

Methods:
We exposed 8 groups of rats (n=8-10/group) for 10 minutes to two different levels of SHS from the following four different types of research reference tobacco: conventional nicotine (~15 mg/g tobacco), reduced nicotine (~0.4 mg/g tobacco), and both conventional and reduced nicotine with added menthol (~1.15 mg/g tobacco) in a 2x2 factorial (ANOVA) design. We also examined a clean air negative control group (n=9). FMD was measured before and after exposures in each rat. To calculate FMD, the femoral artery diameter was measured with micro-ultrasound before and after a 5-min transient ischemia induced by an external vascular occluder. FMD was quantified as the % vasodilation.

Results:
FMD was not affected in the clean air controls (p=0.13). Higher nicotine levels were associated with increased % reduction of FMD impairment (19.22±9.53% vs. 41.07±4.54% (SD); p=0.047). Adding menthol was associated with decreased % reduction of FMD impairment (40.52±4.85% vs. 18.50±9.81%; p=0.048). These two effects were independent (p for nicotine x menthol interaction = 0.6).

Conclusion:
Reduction of nicotine level and addition of menthol each lessen the acute impairment of FMD in rats exposed briefly to tobacco SHS.
Abstract 57: Pharmacologic Inhibition of BK Channels Affects Cardiac Function
Authors: Patel Nishi H , Johannesen Justin H , Goswami Sumanta K , Ponnalagu Devasena , Kohut Andrew R , Singh Harpreet
Published: March 2022

Calcium and voltage activated potassium channels (BK) are ubiquitously distributed, and have been shown to play roles in cardioprotection and cardiac function. To date, however, the effect of BK channel activation or inhibition in cardiac cells has only been studied using
in vitro
or
ex vivo
models. In this study, for the first time we demonstrate the role of BK channels on cardiac function
in vivo
using an antagonist, Paxilline. Male Sprague Dawley rats had an initial echocardiogram to establish baseline values of cardiac function. Afterwards, the femoral vein was isolated and rats injected with either DMSO or Paxilline of various concentrations ranging from 2 ng/mL/kg to 500 μg/mL/kg. Echocardiograms were then repeated 30 seconds, 15 minutes, and 24 hours after injection. Some rats at higher drug dosage suffered cardiac arrest within 15 minutes. In a separate experiment, a pressure transducer was inserted into the left ventricle (LV) via cannulation of the carotid artery. LV Developed Pressure (LVDP) and Heart Rate (HR) were continuously recorded as rats were infused with DMSO or Paxilline via the femoral vein. In agreement with BK null mutant mice, we found that rats receiving Paxilline had a significant decrease in HR compared to controls, as BK is known to play a role in SA nodal cells. In rats that lived, the transient decrease in HR averaged ~26.20%. Rats receiving Paxilline also had diminished Ejection Fraction (EF) ranging from 26.53% to 100% fold-decrease compared to controls. The decrease in EF occurred in a dose dependent manner, with rats receiving higher doses (> 13 ng/mL/kg) of Paxilline typically suffering cardiac arrest within 15 minutes. Measurements using pressure transduction of the LV showed results similar to those rats assessed using echocardiography, with a significant decrease in LVDP ranging from 36.9% to 100% decrease. Rats that received lower doses (<4 ng/mL/kg) of Paxilline showed improvement in their cardiac function back to baseline by 24 hours post injection, suggesting that the effects we observed are transient and that BK inhibition is reversible. We have shown that inhibition of BK is detrimental to cardiac function, suggesting that BK channels in cardiac tissue are not only functional but essential to maintain normal cardiac function.
Abstract 62: Sildenafil Inhibits Neointimal Hyperplasia After Angioplasty, and Reduces Platelet Aggregation
Authors: Yang Han Mo , Jin Sooryeonhwa , Kim Hyo-Soo , Lee Sahmin
Published: March 2022

Background:
Restenosis and stent thrombosis after stent implantation are one of the devating issues in interventional cardiology. Sildenafil has shown its effect in reducing cardiac hypertrophy as well as improving erectile dysfunction through protein kinase G (PKG) activation. Some studies have demonstrated that PKG occupies a central switching role in modulating vascular smooth muscle cell (VSMC) phenotype in response to vascular injury. In this study, we investigated the effects of PKG activation by sidenafil on platelet aggregation and neointimal hyperplasia.

Methods and Results:
In terms of restenosis after vascular injury, sildenafil significantly reduced neointimal hyperplasia in rat carotid arteries compared to control group. This effect of sildenafil was accompanied by the reduction of viability, cell cycle progression, and migration of VSMCs. This was also confirmed in the injured arteries in vivo. Further studies showed that the increased PKG activity by sildenafil inhibited PDGF-stimulated phenotype change of VSMCs from a contractile to a synthetic form. Conversely, the use of PKG inhibitor or gene transfer of dominant-negative PKG reversed the effects of sildenafil, resulting in the increased viability of VSMCs and neointimal formation. In addition, the mice treated with sidenafil showed the facilitated re-endothelialization, compared to control group. Furthermore, we confirmed the effect of sidenafil through PKG activation using cGK-KO mice. Interestingly, sildenafil significantly inhibited platelet aggregation induced by ADP or thrombin. This effect was reversed by PKG inhibitor, suggesting that sildenafil inhibits platelet aggregation via PKG pathway. Furthermore, assays for VASP phosphorylation and P-selectin activation showed the same inhibitory effect of sildenafil on platelet activation.

Conclusions:
This study showed that sildenafil inhibits not only platelet aggregation, but also neointimal hyperplasia through the PKG pathway. These findings suggest that sildenafil could be a promising candidate drug of drug-eluting stents for the prevention of restenosis without other complications such as stent thrombosis.
Abstract 79: Sex-dependent Role of Macrophage-derived Insulin-like Growth Factor-1 in Body Growth, Cardiac Homeostasis and Responses to Cardiac Tissue Stress
Authors: Ilinykh Alexei , Chan Christopher , McLellan Micheal A , Squiers Galen T , Branca Jane , Drummond Grant R , Rosenthal Nadia A , Pinto Alexander R
Published: March 2022

Biological sex is a key factor influencing the development and progression of cardiovascular disease. While sexual dimorphism has been identified in cardiac physiology and sex-based differences are observed in clinical contexts, the molecular and cellular bases for these differences are not understood.

Recently, we found for the first time that female and male hearts are different in their cellular composition. Female hearts comprise significantly greater numbers of resident mesenchymal cells, including cardiac fibroblasts, compared to male hearts, and female hearts consist of differing proportions of multiple leukocyte subsets. We found that these differences are regulated by gonadal hormones.

Extending on our previous work, this study investigates sexual dimorphism in cell-specific IGF-1 production and its impact on cardiac inflammatory responses. IGF-1 is a growth factor that is essential for development and injury responses, and that has been previously shown to function in a sex-dependent manner.

Using genetic, transcriptomic and high-dimensional flow cytometry approaches, we found that macrophages and fibroblasts are the principle IGF-1 producing cells in the heart, with macrophages from female mouse hearts producing twice as much IGF-1 as in males. This contributed to a ~20% greater level of IGF-1 found in the hearts of females compared to males. Furthermore, constitutive genetic ablation of macrophage-derived IGF-1 resulted in ~30% reduction in total IGF-1 in hearts of female mice, whereas no reduction was observed in male hearts. Surprisingly, we also found that ablation of macrophage-derived IGF-1 reduces body weight in female mice by ~10%. Finally, we found that macrophage-derived IGF-1 regulates cardiac inflammatory responses in a sex-dependent manner.

To our knowledge, this is the first study to demonstrate that a macrophage-derived growth factor is essential for normal body growth and plays a sex-dependent role in cardiac inflammatory responses. Our observations provide a cellular and molecular basis for the sexual dimorphism observed in cardiac physiology and pathology, and underscore the importance of considering biological sex in experimental models of cardiac development and disease.
Microangiopathic Hemolytic Anemia and the Development of the Malignant Phase of Hypertension
Authors: GAVRAS HARALAMBOS , BROWN WILLIAM C. B. , BROWN JEHOIADA J. , LEVER ANTHONY F. , LINTON ADAM L. , MACADAM ROBERT F. , MCNICOL GEORGE P. , ROBERTSON J. IAN S. , WARDROP CHARLES
Published: March 2022

Evidence of microangiopathic hemolytic anemia (MHA) was found in 14 of 22 patients with malignant phase hypertension, and in one of these, a patient with proliferative glomerulonephritis, MHA and malignant hypertension developed together during a three-month period of observation.

Among 61 rats subjected to unilateral nephrectomy, injected with DOCA, and given 1% saline to drink, 42 developed evidence of MHA. Eighty-four per cent of these also had fibrinoid necrosis and/or plasmatic vasculosis in the remaining kidney at autopsy. Blood pressure rose to 150 mm Hg or more in 72% of these DOCA-injected animals. In 29 control rats subjected to unilateral nephrectomy only, blood pressure rose to 150 mm Hg or more in 21%, MHA developed in 14%, and fibrinoid lesions were found in none.

The significance of these observations is discussed in relation to the possibility that MHA is either a consequence of malignant hypertension or a contributory factor in its pathogenesis.
Effectiveness of Drug Therapy in Hypertension: Present Status
Authors: FREIS EDWARD D.
Published: March 2022

Progress in the development of effective antihypertensive agents is briefly reviewed. Evidence that drug treatment reduces the incidence of major complications is presented. The recently completed controlled trial carried out in Veterans Administration hospitals indicates that in men with diastolic blood pressure levels of 90 through 114 mm Hg the risk of developing a morbid event over a five-year period was reduced from 55% to 18% by treatment. The degree of benefit was proportional to the risk, which in turn was related directly to the level of blood pressure.
Increased rate of hemorrhage in SOD2-deficient mice following transient focal cerebral ischemia
Authors: Maier Carolina M , Tannous Nicholas J , Chan Pak H
Published: March 2022

7

The development of knock-out (KO) mice with targeted disruption of the inducible manganese superoxide dismutase (SOD2) provided a model for investigating the effects of free radicals by perturbing the enzymatic machinery responsible for their metabolism. Previous research in our laboratory showed that heterozygous SOD2-KO mutants exhibited a 50% decrease in SOD2 activity. These animals were also more susceptible to ischemic damage than their wild-type (WT) counterparts and had a 30% mortality at 24 h following 1 h of focal ischemia. Mortality among SOD2-KO mice was increased when the reperfusion period was extended to 72 h. Therefore, animals in this study (SOD2-KO n=7; WT n=7) were subjected to 30 min of middle cerebral artery occlusion (MCAO), using the intraluminal suture method, which was sufficient to cause extensive and reproducible infarcts at 3 days post-insult as measured from H&E stained sections. Our results showed that 7 out of 7 SOD2-KO animals had hemorrhagic transformations (HT) at 72 h post-MCAO, while only 3 out of 7 WT animals exhibited HT (p=0.02 by Mann-Whitney U-test). Interestingly, the rate of HT did not always correlate with the size or anatomical distribution of the lesion. Hemorrhagic transformations were observed in the ischemic core and ischemic penumbra of both WT and SOD2-KO animals, however the latter also showed HT in histologically undamaged tissue. Three additional animals per group were also injected with Evan’s blue at 64 h post-insult and were perfusion-fixed at 72 h. Fifty μm coronal sections examined under fluorescence showed that SOD2-KO animals had extensive extravasation of the dye compared with their WT counterparts. Previous studies by our group did not show a significant increase in HT in SOD2-KO animals at 24 h post-insult compared with WT controls. This suggests that SOD2-KO animals undergo delayed disruption of the blood-brain barrier integrity and may serve as an ideal model for studying the effects of free radical mediated injury to the vascular endothelium.
Factors Influencing Outcome and Treatment Effect in PROACT II
Authors: Wechsler Lawrence R , Roberts Robin , Furlan Anthony J , Higashida Randall , Dillon William P , Roberts Heidi C , Pettigrew L. Creed , Callahan Alfred , Bruno Askiel , Smith Wade S , Schulz Gregory A
Published: March 2022

17

PROACT II was a randomized controlled trial of intra-arterial thrombolysis with recombinant prourokinase (r-proUK) plus low-dose heparin vs. low-dose heparin alone. In the primary outcome analysis, 40% of patients treated with r-proUK and 25% of control patients had a good neurological recovery at 90 days defined by a modified Rankin score≤2 (p=.043). Objective: To identify prognostic factors for the primary outcome measure and determine whether the treatment effect of r-proUK was consistent across subgroups stratified according to risk.
Methods:
Twenty-seven baseline categorical variables and 11 quantitative variables were selected. Stepwise logistic regression was used to identify important prognostic factors and to create a score which subdivided the study group into risk quartiles. Treatment effect was calculated as an odds ratio (OR) within each quartile and compared with a Breslow-Day test.
Results:
Three baseline variables were identified as strongly influencing the probability of a good outcome; Age ≤ 68 (p<0.0001, OR=4.3), CT hypodensity ≤ 5.25ml (p=0.038, OR=2.1), NIHSS score: (p= 0.0005, OR(11–20)=0.36, OR(>20)=0.085, relative to NIHSS≤10). The effect of treatment in the risk quartiles is summarized in the Table. Comparison of the size of the treatment effect over risk quartiles was non-significant p=0.91.
Conclusion:
Despite stratification of patients based on important prognostic variables there was no evidence of a difference in treatment effect across risk categories. All PROACT eligible patients stand to benefit from early intra-arterial r-proUK treatment.
Baseline ASPECT Scores predict extent of stroke: Interim CT Analysis of CASES
Authors: Hill Michael D , Barber Philip A , Demchuk Andrew M , Pexman Warwick , Buchan Alastair M
Published: March 2022

21

Background
CT scanning remains the fastest and easiest method of neuro-imaging in acute ischemic stroke. The ASPECT score has been shown to be useful in assessing acute CT scans and has demonstrated validity and reliability. Previous studies have not prospectively evaluated early CT ischemia using ASPECTS.
Methods
115 CT scans from the CASES study have been reviewed to date. All baseline and 24–48h follow-up scans were examined by a panel of 3 reviewers. Rating was done by 1 neuroradiologist and 2 of 3 neurologists per session. Consensus was achieved by majority opinion (2 of 3) on each data point. Reviewers were aware of the symptom side but blind to other patient characteristics.
Results
79% of CT scans showed some degree of early ischemic change (ASPECTS < 10). 4.3% of follow up scans were normal (ASPECTS=10) when the baseline ASPECT score was < 9. The baseline ASPECT score was highly associated with the follow-up score (p<0.001) (Figure)
Discussion
Early ischemic change is common on baseline CT scans. A minority of CT scans may be over-interpreted using ASPECTS. Baseline ASPECT score predicts the regions of infarction in follow-up.
Blood Lipids are Important Independent Risk Factors for Ischemic Stroke or TIA: A prospective Follow-up of Over 11,000 patients in The BIP Registry
Authors: Tanne David , Koren Nira , Goldbourt Uri
Published: March 2022

29

Background:
Despite clear associations between blood lipids and coronary heart disease [CHD], and increasing evidence that HMG-CoA reductase inhibitors (statins) reduce the incidence of stroke the associations of blood lipids with stroke are not clear.
Methods:
We followed up 11,177 patients with documented CHD who were screened for but not included in the Bezafibrate Infarction Prevention (BIP) study, a secondary prevention randomized clinical trial of lipid modification, and had no history of stroke, for subsequent cerebrovascular disease (CVD). During a 6 to 8 year follow- up period 941 patients had a non-hemorrhagic CVD, of whom 487 were verified ischemic strokes or TIAs.
Results:
Age-adjusted rates of non-hemorrhagic CVD (per 1000 person-years)increased with increasing quintiles of total cholesterol and of LDL cholesterol from 10 to 14, increased with increasing quintiles of triglycerides from 9 to 17, and decreased with increasing quintiles of HDL cholesterol and percent of total serum cholesterol contained in the HDL moiety (%HDL) from 15 to 9 and from 18 to 9 per 1000 person years, respectively (p<0.01 for all). Similar trends appeared for the end-point of verified ischemic stroke/TIA. In separate logistic regression models, adjusting for clinical covariates, the following odds ratios (95% CI) were identified for lipid values in the upper versus the lower tertile for the end-point of ischemic stroke/TIA: total cholesterol 1.50 (1.18 to 1.90); LDL cholesterol 1.43 (1.12 to 1.82), HDL cholesterol 0.72 (0.56 to 0.93) and %HDL 0.68 (0.53 to 0.86). Odds ratio associated with triglycerides >200mg/dl compared to lower levels was 1.47 [95%CI 1.19 to 1.80].
Conclusions:
These findings clearly support the role of blood lipids including total cholesterol, LDL cholesterol, HDL cholesterol, %HDL, and triglycerides in prediction of ischemic stroke/TIA among patients with established CHD.
Stroke Risk Profile Predicts Brain Volume and Cognitive Function in Stroke-free Subjects: The Framingham Study
Authors: Seshadri Sudha , Wolf Philip A , Beiser Alexa , Elias Merrill F , Au Rhoda , Kase Carlos S , D’Agostino Ralph B , DeCarli Charles
Published: March 2022

30

Background:
The contribution of stroke risk factors to the pervasive brain atrophy and cognitive impairment seen with aging is controversial. This is partly due to a paucity of longitudinal data in stroke-free subjects. We hypothesize, that even in subjects who remain free of clinical stroke, exposure to stroke risk factors may adversely impact brain volume. Objective: To prospectively examine the association of Framingham Stroke Risk Profile (FSRP) scores at baseline with MRI brain volume on follow-up, and to further evaluate the association of brain volume with cognitive function, in a population-based cohort of stroke- and dementia-free subjects.
Methods:
Framingham Offspring Study subjects were evaluated for stroke risk factors at exam 5 (1991–1995). A sex-specific, composite FSRP score was calculated for each subject, as validated in prior studies. 909 subjects (age range 42–82, mean age: 61 years, 427 men), who remained free of clinical dementia and stroke, underwent quantitative MRI imaging and neuropsychological evaluation, 4 to 9 years later (1999–2000). Using linear regression models adjusted for age and sex, we examined the association between the FSRP score and Total Cerebral Brain Volume- TCBV (expressed as a ratio of total cranial volume). We also evaluated the association of TCBV with age- and education- adjusted scores on a battery of neuropsychological tests administered at the time of imaging.
Results:
There was a strong inverse association between TCBV and the FSRP score (p=0.002). TCBV also showed a significant positive association with performance on tests of manual dexterity (e.g. finger tapping; p<0.05) and visual memory (e.g. delayed visual reproduction (p<0.01) but not with performance on tests of naming or logical memory (p>0.05).
Conclusion:
An adverse stroke risk profile predicted lower MRI brain volume, which in turn was associated with poorer performance on specific neuropsychological tests suggestive of vascular cognitive impairment. Pathogenetic mechanisms for these associations in stroke-free subjects could include various vascular causes for accelerated brain aging and merit further study.
Incidence of Secondary Stroke and Myocardial Infarction Based on Managed Care Administrative Data
Authors: Vickrey Barbara G , Rector Thomas , Sloss Elizabeth , Wickstrom Steven , Garber Steven , McCaffrey Daniel , Guzy Peter , Gorelick Philip B , Levin Regina
Published: March 2022

32

Background:
Little data exist on the incidence of subsequent acute ischemic events in persons with established atherosclerotic vascular disease in managed care plans. Objective: To estimate the incidence of secondary stroke and myocardial infarction (MI) over 3 years.
Methods:
Patients were identified as having atherosclerotic vascular disease (either stroke, MI, or peripheral arterial disease {PAD}) using administrative data from 11 UnitedHealthcare plans (3 with Medicare) from 1995–98. The stroke cohort includes patients ≥ 40 years old hospitalized with a primary or secondary ICD-9-CM code of either 434 or 436, and length of stay ≥ 1 day. Patients with a carotid endarterectomy or claims consistent with cardioembolic strokes were excluded. Persons age ≥ 40 with a primary ICD-9-CM code of 410 and a length of stay ≥ 2 days were included in the MI cohort. The PAD cohort included patients ≥ 40 with a hospital admission or an office visit with an ICD-9-CM code of 440.2x or 440.3. Cumulative incidences of subsequent stroke or MI were estimated for each cohort using Kaplan-Meier survival analysis.
Results:
For stroke, MI, and PAD cohorts, 3527 (49% Medicare), 9039 (26% Medicare), and 10,925 (46% Medicare) members were identified, respectively. Nearly 96% of MI and 89% of stroke patients were discharged alive. During an average follow-up period of 12 months in the stroke cohort, the cumulative incidences of stroke or MI were 4%, 7%, 12% and 14% at 0.5, 1, 2, and 3 years, respectively. Incidences in the MI cohort were 4%, 6%, 8% and 11% at 0.5, 1, 2, and 3 years (mean follow-up=15 months). In the PAD cohort with a mean follow-up of 15 months, the cumulative percentages with subsequent AMI or stroke were 2%, 3%, 5% and 8% after 0.5, 1, 2, and 3 years. Stroke accounted for 79%, 16%, and 39% of the secondary events in the stroke, MI, and PAD cohorts, respectively.
Conclusions:
Among persons with atherosclerotic vascular disease enrolled in managed care plans around the US, the incidence of subsequent ischemic events is consistent with a significant burden of symptomatic disease. Among stroke patients who have a subsequent ischemic event, stroke is the secondary event in the vast majority of cases.
White Matter Damage is Associated with Matrix Metalloproteinases in Binswanger’s Disease
Authors: Rosenberg Gary A , Sullivan Nicky , Esiri Margaret M
Published: March 2022

81

BACKGROUND:
Binswanger’s disease (BD) is a progressive form of vascular dementia (VaD) of the elderly associated pathologically with demyelination and clinically with disturbances of gait and intellect. It is commonly found in patients with fibrinoid and hyaline changes in brain arterioles secondary to long-standing hypertension. Because of the remodeling seen in the blood vessel wall, and the role of the matrix metalloproteinases (MMPs) in extracellular matrix injury and repair, we hypothesized that disturbances in the MMPs may be involved in the BD type of VaD.
METHODS:
To test the hypothesis, brain tissues from five patients with VaD of the BD or multi-infarct type were immunostained with antibodies to glial fibrillary acidic protein (GFAP), a macrophage/microglial cell marker (PG-M1), gelatinase A (MMP-2), stromelysin-1 (MMP-3), and gelatinase B (MMP-9). Control tissues were from eight elderly patients: four with strokes without dementia, and four without neurological diseases.
RESULTS:
Macrophage/microglia (PG-M1)-positive cells appeared around infarcts both in cases with strokes without dementia, and in those with VaD. In two of the three BD patients PG-M1 cells were prominent near damaged arterioles and scattered diffusely in white matter. MMP-2 was seen normally in perivascular macrophages and astrocytic processes near blood vessels, and was present in patients with strokes in reactive astrocytes, particularly those with a gemistocytic shape. MMP-9 was seen only in acute lesions. MMP-3 was seen in PG-M1 staining microglia/macrophage cells around the acute infarctions. In BD MMP-3 persisted in tissue macrophages, disappearing in long-standing white matter gliosis.
CONCLUSIONS:
These observations suggest that MMPs participate in the demyelination associated with injured blood vessels in the BD form of VaD. Chronic inflammation, which may be amenable to treatment, may be a factor in the progressive forms of VaD.
Inflammatory markers in progressing lacunar stroke
Authors: Castellanos Mar , Castillo Jose , Chamorro Angel , Leira Rogelio , Serena Joaquin , Davalos Antonio
Published: March 2022

89

Background:
The mechanisms underlying neurologic deterioration in patients with lacunar infarction have not been established. While accumulating evidence suggest a role for inflammatory-mediated damage after brain ischemia, whether inflammation also intervenes in lacunar stroke progression remains unsettled. Objective: We sought to investigate the role of inflammatory markers in the progression of lacunar infarctions
Methods:
We studied within the first 24 hours after the onset of symptoms 113 consecutive patients (mean age 69.7±9.3, 57% males) with lacunar stroke defined by clinical and CT/MRI criteria (lacunar syndrome + lesion of < 15mm in appropriate location). Neurological deterioration was defined as a fall of 1 or more points in Canadian Stroke Scale (CSS) between inclusion and 48 hours. Interleukine 6 (IL-6), tumor necrosis factor-α (TNF-α) and ICAM-1 were determined by ELISA in blood samples obtained on admission.
Results:
At follow up, 27 patients (23.9%) progressed on the CSS. Among risk factors and clinical characteristics, only a history of hypertension, and a lack of prior treatment with aspirin, were significantly more frequent in patients with neurologic deterioration (p<0.05). Serum TNF-α (17.3±5.02 vs 8.7±4.7 pg/mL), IL-6 (29.2±7.2 vs 13.7±7.5 pg/mL) and ICAM-1 (270.6±65.0 vs 160.6±29.8 pg/mL) were significantly higher in patients who progressed (p<0.001). Logistic regression analyses adjusted for history of hypertension and prior aspirin intake showed that TNF−α [OR=1.36, 95% CI (1.20–1.53)], IL-6 [OR=1.25, 95% CI (1.14–1.36)] and ICAM-1 [by 10 pg/mL, OR=2.85, 95% CI (2.79–2.91)] were related to lacunar stroke progression.
Conclusions:
Our results suggest that inflammation contributes to the progression of lacunar infarctions. Further studies will establish the mechanisms underlying this provocative finding that opens a new therapeutic avenue in lacunar stroke.
Cost effectiveness of new antiplatelet agents in secondary stroke prevention
Authors: Kernan Walter N , Fayad Pierre , Rizzo John A
Published: March 2022

93

Objective.
To determine the cost effectiveness of new antiplatelet agents.
Methods.
From a payor perspective, we performed cost-effectiveness and cost-utility analyses of ticlopidine, clopidogrel, or combination aspirin/dipyridamole, each compared with aspirin alone for secondary prevention of stroke. Our target population was men and women with cerebrovascular disease, divided into 4 groups by severity of baseline symptoms. Simulation models incorporated data on drug effectiveness, drug and stroke treatment costs, and quality of life for stroke survivors. Cost effectiveness was expressed as cost/stroke averted and cost utility as cost/quality-adjusted life year (QALY).
Results.
The average annual cost effectiveness over 2 years for patients with TIA, mild, moderate, or severe stroke was $170,188, $177,304, $206,245, and $220,716, respectively, for clopidogrel; $59,131, $66,247, $95,188, and $109,659 for ticlopidine; and $22,080, $29,196, $58,137, and $72,608 for aspirin/dipyridamole. The annual cost utility for patients with TIA, mild, moderate, or severe stroke was $113,620, $187,421, $436,027, and $933,240, respectively, for clopidogrel; $39,477, $70,027, $201,239, and $463,664 for ticlopidine; and $14,741, $30,862, $122,909, and $307,004 for aspirin/dipyridamole. To fall below the threshold of $50,000, the relative risk reduction among TIA patients would need to increase from 8.7% to 15.1% for clopidogrel. For the cost utility of ticlopidine or aspirin/dipyridamole to rise above $50,000, effectiveness among TIA patients would need to fall from 21.0% to 18.5% and 23.1% to 13.8%, respectively.
Conclusion.
According to criteria of <50,000/QALY, both aspirin/dipyridamole and ticlopidine are cost effective compared to aspirin alone for secondary stroke prevention among patients with TIA. Aspirin/dipyridamole is also cost effective in mild stroke. No agent had a cost utility ratio <$100,000 for moderate or severe stroke. Our findings are limited by the absence of research directly comparing the effectiveness of new antiplatelet agents; conclusions about the relative cost effectiveness of new agents should, therefore, be made cautiously.
Isolated lateral sinus thrombosis: 43 cases
Authors: Crassard Isabelle , Wolff Valerie , Ameri Alain , Biousse Valerie , Bousser Marie-Germaine
Published: March 2022

P4

Background and Objective:
Since the preantibiotic era, where isolated lateral sinus thrombosis (isolated LST) was known as “otitic hydrocephalus”, little attention has been paid to this variety of cerebral venous thrombosis (CVT). We therefore reviewed all cases of isolated LST prospectively collected in our center over 25 years.
Methods:
Among 185 patients with CVT examined between 1975 and April 2000, we identified 135 patients with LST and among them 43 patients with isolated LST. Diagnosis was based on conventional angiography and/or magnetic resonance imaging and/or helical cerebral CT venography. Clinical, etiologic and prognostic features were studied and compared with those of the other 142 CVT cases.
Results:
43 patients (23%; 28 female, 15 male) had isolated LST: right in 17, left in 25, bilateral in 1. The main clinical symptoms were headache (88%), papilledema (44%), seizures (28%), motor or sensory deficit (19%), multiple cranial nerves palsy (19%), altered consciousness (9%), dysphasia (9%). The single common pattern of presentation was isolated intracranial hypertension in 20 patients (47%). Four patients had isolated headaches (9%) and 19 (44%) had at least one focal sign (deficits and/or partial seizures). Compared with the other 142 CVT cases, presentation with isolated headaches or intracranial hypertension was more frequent (p=0.02) and altered consciousness or partial seizure less common (p=0.01; p=0.004). Numerous causes or predisposing factors were identified among them septic and local causes represented respectively 14% and 19%. The association of both was significantly more frequently found that in other CVT patients (p=0.01). Treatment consisted of anticoagulation in 32 patients (74%). Complete recovery occurred in 37 patients (86%), 5 patients had sequelea (12%) and 1 died of a carcinoma (2%), compared with respectively 71.5%, 24% and 4.5% for the other 142 CVT cases (no significant difference).
Conclusion:
The isolated LST is a frequent variety of CVT, presenting in a majority of cases with isolated intracranial hypertension or headache. Septic and local causes are more frequent that in other variety of CVT and require specific treatment. Its prognosis is usually good.
Multifocal signal loss lesions on T2*-weighted gradient echo MRI are not a predictor of hemorrhagic vs. ischemic stroke in patients with advanced leukoaraiosis.
Authors: Kim Dong-Eog , Bae Hee-Joon , Lee Seung-Hoon , Kim Ho , Yoon Byung-Woo , Roh Jae-Kyu
Published: March 2022

P20

Objective:
To determine whether multifocal signal loss lesions (MSLL) on T2*-weighted gradient echo MRI (GE-MRI) are always more strongly associated with hemorrhagic stroke (ICH) than ischemic stroke (infarction).
Background:
MSLL on GE-MRI represent previous microbleeds, which may be a direct marker of increased vascular fragility. Thus, GE-MRI might enable recognition of the bleeding-prone microangiopathy and prediction of a patient’s hemorrhagic risk. However, if MSLL reflect microangiopathy, they will also be associated with leukoaraiosis; the latter is commonly associated with occlusive-type vascular lesions.
Methods:
We studied 72 consecutive acute stroke patients (43 men and 29 women, 64.9 ± 10.5 years, 31 ICH and 41 infarction) with hypertension and no cardiac source of embolism who were admitted to our hospital from March 1997 to July 1998. GE-MRI was used to count MSLL which were defined as focal areas of homogeneous round signal loss with a diameter of up to 5 mm. Leukoaraiosis was classified into none-or-mild (absent, punctate) and advanced (early confluent, confluent) white-matter hyperintensities. We also counted lacunae. Multiple logistic regression analysis was used to evaluate the relative contributions of MSLL, leukoaraiosis, and lacunae in discriminating between ICH and infarction. Leukoaraiosis was analyzed as a dummy variable (none-or-mild vs. advanced).
Results:
The association between MSLL and ICH significantly differed by leukoaraiosis (
p
= 0.003 for MSLL-leukoaraiosis interaction term). The number of MSLL on GE-MRI was significantly more strongly associated with ICH than infarction (odds ratio [OR], 2.06; 95% confidence interval [CI], 1.29 to 3.30) when leukoaraiosis was none-or-mild. However, the presence of advanced leukoaraiosis produced a decrease in the OR of MSLL to 1.01. ([CI], 0.98 to 1.05)
Conclusion:
Our study shows that MSLL on GE-MRI are not a predictor of ICH vs. infarction in patients with advanced leukoaraiosis. Therefore, in the evaluation of GE-MRI for bleeding-prone microangiopathy, the extent of leukoaraiosis should always be considered.