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Stroke has multiple etiologies, but the underlying genes and pathways are largely unknown. We conducted a multiancestry genome-wide-association meta-analysis in 521,612 individuals (67,162 cases and 454,450 controls) and discovered 22 new stroke risk loci, bringing the total to 32. We further found shared genetic variation with related vascular traits, including blood pressure, cardiac traits, and venous thromboembolism, at individual loci (n = 18), and using genetic risk scores and linkage-disequilibrium-score regression. Several loci exhibited distinct association and pleiotropy patterns for etiological stroke subtypes. Eleven new susceptibility loci indicate mechanisms not previously implicated in stroke pathophysiology, with prioritization of risk variants and genes accomplished through bioinformatics analyses using extensive functional datasets. Stroke risk loci were significantly enriched in drug targets for antithrombotic therapy.

Background and Purpose: Accurate diagnosis of acute aortic dissection (AAD) is sometimes difficult because of accompanying central nervous system (CNS) symptoms. The purpose of this study was to investigate the clinical characteristics of Type A AAD (TAAAD) with CNS symptoms., Methods: We retrospectively reviewed the medical records of 8403 patients ambulanced to our emergency and critical care center between April 2009 and May 2014., Results: We identified 59 TAAAD patients for the analysis (mean age, 67.3±10.5years; 37 (62.0%) male). Eleven patients (18.6%) presented CNS symptoms at the onset of TAAAD, and these patients complained less frequently of typical chest and back pain than those without CNS symptoms (p<0.0001). Initial systolic and diastolic blood pressure were lower (p=0.003, and p=0.049, respectively) and involvement of the supra-aortic artery was more frequent in patients with CNS symptoms (p<0.0001)., Conclusion: Because CNS symptom can mask chest and back pain caused by TAAAD, physicians should always consider the possibility of TAAAD in patients with CNS symptoms in emergency medicine settings., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background and purpose Previous studies have suggested that atrial septal aneurysm is a potential risk factor for cerebral embolism. However, the association between the level of atrial septal protrusion and cerebral embolism is still unclear. The purpose of the present study was to assess the association between the maximal distance of atrial septal protrusion and cryptogenic stroke. Methods A total of 588 consecutive acute ischemic stroke patients (70 ± 11 (mean ± SD) years, 401 men) who underwent transesophageal echocardiography were enrolled. The maximal distance of atrial septal protrusion into the right or left atrium was measured. Atrial septal aneurysm was diagnosed when the maximal distance of atrial septal protrusion was >10 mm. Cryptogenic stroke was defined as non-lacunar ischemic stroke without >50% proximal artery stenosis or occlusion, cardioembolic sources, ≥4 mm atherosclerotic plaques in the aortic arch, or carotid or vertebral artery dissection. Results The rate of cryptogenic stroke increased with the increasing maximal distance of atrial septal protrusion. The maximal distance of atrial septal protrusion (multivariate-adjusted odds ratio (OR) per 1 mm, 1.14; 95% confidence interval (CI), 1.04-1.24; P = 0.003) and atrial septal aneurysm (multivariate-adjusted OR, 4.32; 95% CI, 1.22-20.39; P = 0.022) was independently associated with cryptogenic stroke. Conclusions The maximal distance of atrial septal protrusion was independently associated with cryptogenic stroke.

Background and Purpose: The role of early hospital arrival in improving poststroke clinical outcomes in patients without reperfusion treatment remains unclear. This study aimed to determine whether early hospital arrival was associated with favorable outcomes in patients without reperfusion treatment or with minor stroke., Methods: This multicenter, hospital-based study included 6780 consecutive patients (aged, 69.9±12.2 years; 63.9% men) with ischemic stroke who were prospectively registered in Fukuoka, Japan, between July 2007 and December 2014. Onset-to-door time was categorized as T 0-1 , ≤1 hour; T 1-2 , >1 and ≤2 hours; T 2-3 , >2 and ≤3 hours; T 3-6 , >3 and ≤6 hours; T 6-12 , >6 and ≤12 hours; T 12-24 , >12 and ≤24 hours; and T 24- , >24 hours. The main outcomes were neurological improvement (decrease in National Institutes of Health Stroke Scale score of ≥4 during hospitalization or 0 at discharge) and good functional outcome (3-month modified Rankin Scale score of 0-1). Associations between onset-to-door time and main outcomes were evaluated after adjusting for potential confounders using logistic regression analysis., Results: Odds ratios (95% confidence intervals) increased significantly with shorter onset-to-door times within 6 hours, for both neurological improvement ( T 0- 1 , 2.79 [2.28-3.42]; T 1-2 , 2.49 [2.02-3.07]; T 2-3 , 1.52 [1.21-1.92]; T 3-6 , 1.72 [1.44-2.05], with reference to T 24- ) and good functional outcome ( T 0-1 , 2.68 [2.05-3.49], T 1-2 2.10 [1.60-2.77], T 2-3 1.53 [1.15-2.03], T 3-6 1.31 [1.05-1.64], with reference to T 24- ), even after adjusting for potential confounding factors including reperfusion treatment and basal National Institutes of Health Stroke Scale. These associations were maintained in 6216 patients without reperfusion treatment and in 4793 patients with minor stroke (National Institutes of Health Stroke Scale ≤4 on hospital arrival)., Conclusions: Early hospital arrival within 6 hours after stroke onset is associated with favorable outcomes after ischemic stroke, regardless of reperfusion treatment or stroke severity., (© 2017 American Heart Association, Inc.)

Background and Purpose: The prediction of genetic predispositions to ischemic stroke (IS) may allow the identification of individuals at elevated risk and thereby prevent IS in clinical practice. Previously developed weighted multilocus genetic risk scores showed limited predictive ability for IS. Here, we investigated the predictive ability of a newer method, polygenic risk score (polyGRS), based on the idea that a few strong signals, as well as several weaker signals, can be collectively informative to determine IS risk., Methods: We genotyped 13 214 Japanese individuals with IS and 26 470 controls (derivation samples) and generated both multilocus genetic risk scores and polyGRS, using the same derivation data set. The predictive abilities of each scoring system were then assessed using 2 independent sets of Japanese samples (KyushuU and JPJM data sets)., Results: In both validation data sets, polyGRS was shown to be significantly associated with IS, but weighted multilocus genetic risk scores was not. Comparing the highest with the lowest polyGRS quintile, the odds ratios for IS were 1.75 (95% confidence interval, 1.33-2.31) and 1.99 (95% confidence interval, 1.19-3.33) in the KyushuU and JPJM samples, respectively. Using the KyushuU samples, the addition of polyGRS to a nongenetic risk model resulted in a significant improvement of the predictive ability (net reclassification improvement=0.151; P<0.001)., Conclusions: The polyGRS was shown to be superior to weighted multilocus genetic risk scores as an IS prediction model. Thus, together with the nongenetic risk factors, polyGRS will provide valuable information for individual risk assessment and management of modifiable risk factors., (© 2016 The Authors.)

Pericytes are mural cells abundantly present in cerebral microvessels and play important roles, including the formation and maintenance of the blood-brain barrier. Nox4 is a major source of reactive oxygen species in cardiovascular cells and modulate cellular functions, particularly under pathological conditions. In the present study, we found that the expression of Nox4 was markedly induced in microvascular cells, including pericytes, in peri-infarct areas after middle cerebral artery occlusion stroke models in mice. The upregulation of Nox4 was greater in a permanent middle cerebral artery occlusion model compared with an ischemia/reperfusion transient middle cerebral artery occlusion model. We performed permanent middle cerebral artery occlusion on mice with Nox4 overexpression in pericytes (Tg-Nox4). Infarct volume was significantly greater with enhanced reactive oxygen species production and blood-brain barrier breakdown in peri-infarct areas in Tg-Nox4, compared with littermate controls. In cultured brain pericytes, Nox4 was significantly upregulated by hypoxia and was promptly downregulated by reoxygenation. Phosphorylation of NFκB and production of matrix metalloproteinase 9 were significantly increased in both cultured pericytes overexpressing Nox4 and in peri-infarct areas in Tg-Nox4. Collectively, Nox4 is upregulated in pericytes in peri-infarct areas after acute brain ischemia and may enhance blood-brain barrier breakdown through activation of NFκB and matrix metalloproteinase 9, thereby causing enlargement of infarct volume., (© The Author(s) 2015.)

The neurovascular unit (NVU), a minimal unit to exert neurological functions, is composed of neurons, astrocytes, endothelial cells, pericytes, and extracellular matrix proteins forming basal membranes. The cell components interact with one another and function cooperatively under both physiological and pathological conditions. Pericytes and astrocytes participate crucially in the formation and maintenance of the blood-brain barrier (BBB), the tight junction formed by endothelial cells, and regulate cerebral blood flow in response to neurological activities. The BBB actively regulate molecular import and export. The concept of the NVU is also useful for understanding pathogenesis and exploring therapeutic targets in various CNS disorders. In this review, recent research advances regarding the NVU and its components in health and ischemic stroke are summarized.

A 62-year-old man complained of gait disturbance, bladder and bowel dysfunction and paresthesia of both legs one month before admission. His symptoms were suggestive of cauda equina syndrome. After admission, he developed rapid progressive numbness and weakness of both legs and a disturbance of consciousness. A random skin biopsy was performed and a histological diagnosis of intravascular large B cell lymphoma (IVLBCL) was reached. His symptoms were improved after rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) therapy.

Background: Oral anticoagulants (OACs) reduce the incidence of embolic events associated with non-valvular atrial fibrillation (NVAF); however, ischemic stroke can still occur in such patients. Although there are various causes of ischemic stroke in patients with NVAF, their medication status at onset has scarcely been studied. This retrospective study aimed to determine the underlying causes of ischemic stroke in patients with NVAF in relation to pre-stroke anticoagulation., Methods: Among Japanese patients with acute ischemic stroke enrolled in the Fukuoka Stroke Registry from June 2007 to May 2013, 1,302 patients with NVAF who had been hospitalized within 24 h of onset were included in this study, and their backgrounds, pre-stroke use of OACs and prothrombin time-international normalized ratio (PT-INR) on admission were investigated. Strokes were regarded as being non-cardioembolic (CE) type when causes other than NVAF had been identified. The sub-therapeutic range (TR) for warfarin was defined according to Japanese guidelines for pharmacotherapy of atrial fibrillation., Results: Atrial fibrillation had been diagnosed prior to onset of stroke in 704 of 1,302 patients (54%). However, it had not been detected before or on admission, but identified later during hospitalization in 270 patients (21%). Of the patients who had atrial fibrillation on admission but had not been diagnosed as having it, 108 (8%) had not received any medication before onset of stroke and 220 (17%) had received medications other than OACs. OACs had been administered to 415 (59%) of the patients with known atrial fibrillation. The proportion of pre-stroke CHADS2 or CHA2DS2-VASc scores ≥1 ranged from 93 to 99% depending on whether atrial fibrillation had been diagnosed or anticoagulation therapy administered before stroke onset. The PT-INR was in the sub-TR on admission in 283 of 399 patients (71%) receiving warfarin. Male sex, smoking and previous stroke were more prevalent in patients with values within or over the TR of PT-INR than in those in the sub-TR. Non-CE stroke was more prevalent in patients with values above the lower therapeutic limit of the recommended PT-INR than in those in the sub-TR (p < 0.001). The number of CE strokes was much smaller in patients with high admission PT-INR values; this was not observed for non-CE ischemic strokes (p < 0.001)., Conclusions: In the clinical setting, under-diagnosis, underuse and sub-therapeutic doses of OACs are major causes of ischemic stroke in patients with NVAF. However, non-CE ischemic strokes may develop in patients receiving therapeutic doses of warfarin., (© 2016 S. Karger AG, Basel.)

Unlabelled: Elevated levels of reactive oxygen species (ROS) in the vascular wall play a key role in the development of neointimal hyperplasia. Nox4-based NADPH oxidase is a major ROS generating enzyme in the vasculature, but its roles in neointimal hyperplasia remain unclear., Objective: Our purpose was to investigate the role of smooth muscle cell (SMC) Nox4 in neointimal hyperplasia., Approach and Results: Mice overexpressing a human Nox4 mutant form, carrying a P437H dominant negative mutation (Nox4DN) and driven by SM22α promoter, to achieve specific expression in SMC, were generated in a FVB/N genetic background. After wire injury-induced endothelial denudation, Nox4DN had significantly decreased neointima formation compared with non-transgenic littermate controls (NTg). ROS production, serum-induced proliferation and migration, were significantly decreased in aortic SMCs isolated from Nox4DN compared with NTg. Both mRNA and protein levels of thrombospondin 1 (TSP1) were significantly downregulated in Nox4DN SMCs. Downregulation of TSP1 by siRNA decreased cell proliferation and migration in SMCs. Similar to Nox4DN, downregulation of Nox4 by siRNA significantly decreased TSP1 expression level, cell proliferation and migration in SMCs., Conclusions: Downregulation of smooth muscle Nox4 inhibits neointimal hyperplasia by suppressing TSP1, which in part can account for inhibition of SMC proliferation and migration., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Thioredoxin 1 (Trx1) is а antioxidant protein that regulates protein disulfide bond reduction, transnitrosylation, denitrosylation and other redox post-translational modifications. In order to better understand how Trx1 modulates downstream protective cellular signaling events following cardiac ischemia, we conducted an expression proteomics study of left ventricles (LVs) after thoracic aortic constriction stress treatment of transgenic mice with cardiac-specific over-expression of Trx1, an animal model that has been proven to withstand more stress than its non-transgenic littermates. Although previous redox post-translational modifications proteomics studies found that several cellular protein networks are regulated by Trx1-mediated disulfide reduction and transnitrosylation, we found that Trx1 regulates the expression of a limited number of proteins. Among the proteins found to be upregulated in this study was SET and MYND domain-containing protein 1 (SMYD1), a lysine methyltransferase highly expressed in cardiac and other muscle tissues and an important regulator of cardiac development. The observation of SMYD1 induction by Trx1 following thoracic aortic constriction stress is consistent with the retrograde fetal gene cardiac protection hypothesis. The results presented here suggest for the first time that, in addition to being a master redox regulator of protein disulfide bonds and nitrosation, Trx1 may also modulate lysine methylation, a non-redox post-translational modification, via the regulation of SMYD1 expression. Such crosstalk between redox signaling and a non-redox PTM regulation may provide novel insights into the functions of Trx1 that are independent from its immediate function as a protein reductase., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Objectives: The association between hematocrit levels and the risk of cardiovascular disease (CVD) has been reported inconsistently. We aimed to investigate the association of hematocrit levels with the development of stroke and coronary heart disease (CHD) in a general Japanese population., Methods: A total of 2585 community-dwelling Japanese individuals aged 40 years or older in 1988 were followed up for 19 years. These subjects were divided into four groups according to the sex-specific quartiles of hematocrit at baseline., Results: During the follow-up, 301 subjects developed stroke (210 ischemic and 91 hemorrhagic) and 187 developed CHD. The risk of ischemic stroke was higher in both the lowest (Q1: men, ≤44.7%; women, ≤39.3%) and the highest (Q4: men, ≥49.7%; women, ≥43.8%) quartiles than in the third quartile (Q3: men, 47.1%-49.6%; women, 41.7%-43.7%) used as a reference (multivariable-adjusted hazard ratios [95% confidence intervals]: Q1, 1.55 [0.99-2.43]; Q2, 1.44 [0.93-2.23]; Q3, 1.00; and Q4, 1.62 [1.06-2.50]; P = 0.86 for trend). In contrast, hematocrit levels and the risk of hemorrhagic stroke showed a linear inverse association (Q1, 1.91 [1.03-3.54]; Q2, 1.26 [0.68-2.34]; Q3, 1.00; and Q4, 0.81 [0.41-1.61]; P = 0.009 for trend). The risk of CHD increased significantly in Q4 (Q1, 1.13 [0.71-1.80]; Q2, 1.08 [0.69-1.71]; Q3, 1.00; and Q4, 1.60 [1.04-2.46]; P = 0.13 for trend)., Conclusions: Our findings suggest that both elevated and decreased hematocrit levels are associated with an increased risk of CVD, but the influence of hematocrit is different among subtypes of CVD., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Background: Involvement of central nervous system is very common in Behçet disease, known as neuro-Behçet disease (NBD). However, there have been few reports which evaluated stroke-like cerebral small-vessel disease associated with Behçet disease., Objective: We evaluated cerebral small-vessel lesions by using magnetic resonance imaging in 2 patients with NBD., Clinical Cases: In a 41-year-old woman case, who developed dysarthria and left hemiparesis, diffusion-weighted images (DWI) showed small high-intensity areas in the bilateral internal capsule. The right lesion had a low apparent diffusion coefficient (ADC) value, whereas the left one had a high value. In a 59-year-old woman case, who developed dysarthria and left hemihypesthesia, DWI showed high-intensity areas in the right side of the pons and in the right peduncle of the midbrain. The lesion in the pons had a low ADC value, whereas the lesion in the midbrain had a high value. ADC map may be useful to identify symptomatic lesions in the brain, because only the lesions with low ADC values were symptomatic., Conclusions: NBD should be considered in those who had not had any risk factors for ischemic stroke but experienced cerebral small-vessel disease., (Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Background and Purpose: The relationship between blood pressure (BP) variability and functional outcome in patients with acute ischemic stroke remains unclear. This study aimed to elucidate whether in-hospital day-by-day BP variability is associated with functional outcome after acute ischemic stroke., Methods: Using the Fukuoka Stroke Registry, we included 2566 patients with a first-ever ischemic stroke who had been functionally independent before the onset and were hospitalized within 24 hours. BP was measured daily, and its variability was assessed by SD, coefficients of variance, and variations independent of mean. Poor functional outcome was assessed by modified Rankin Scale scores ≥3 at 3 months., Results: After adjustment for multiple confounding factors including age, sex, risk factors, stroke features, baseline severity, thrombolytic therapy, antihypertensive agents, and mean BP, day-by-day BP variability during the subacute stage (4-10 days after onset) was independently associated with a poor functional outcome (multivariable-adjusted odds ratios [95% confidence interval] in the top versus bottom quartile of systolic BP variability, 1.51 [1.09-2.08] for SD; 1.63 [1.20-2.22] for coefficients of variance; 1.64 [1.21-2.24] for variations independent of mean). Similar trends were also observed for diastolic BP variability. These trends were unchanged in patients who were not treated with antihypertensive drugs. In contrast, no association was found between indices of BP variability during the acute stage and functional outcome after adjusting for potential confounders., Conclusions: These data suggest that intraindividual day-by-day BP variability during the subacute stage is associated with the 3-month functional outcome after acute ischemic stroke., (© 2015 American Heart Association, Inc.)

Background and Purpose: Variable sex differences in clinical outcomes after stroke have been reported worldwide. This study aimed to elucidate whether sex is an independent risk factor of poor functional outcome after acute ischemic stroke., Methods: Using the database of patients with acute stroke registered in the Fukuoka Stroke Registry in Japan from 1999 to 2013, 6236 previously independent patients with first-ever ischemic stroke who were admitted within 24 hours of onset were included in this study. Baseline characteristics were assessed on admission. Study outcomes included neurological improvement, neurological deterioration, and poor functional outcome (modified Rankin Scale score, 3-6 at discharge). Logistic regression analyses were performed to evaluate the association between sex and clinical outcomes., Results: Overall, 2398 patients (38.5%) were women. Severe stroke (National Institutes of Health Stroke Scale score, ≥8) on admission was more prevalent in women than in men. The frequency of neurological improvement or deterioration during hospitalization was not different between the sexes. After adjusting for possible confounders, including age, stroke subtype and severity, risk factors, and poststroke treatments, it was found that female sex was independently associated with poor functional outcome at discharge (odds ratio, 1.30; 95% confidence interval, 1.08-1.57). There was heterogeneity of the association between sex and poor outcome according to age: women had higher risk of poor outcome than men among patients aged ≥70 years, but no clear sex difference was found in patients aged <70 years., Conclusions: Female sex was associated with the risk of poor functional outcome at discharge after acute ischemic stroke., (© 2014 American Heart Association, Inc.)

Fibrosis is concomitant with repair processes following injuries in the central nervous system (CNS). Pericytes are considered as an origin of fibrosis-forming cells in the CNS. Here, we examined whether platelet-derived growth factor receptor β (PDGFRβ), a well-known indispensable molecule for migration, proliferation, and survival of pericytes, was involved in the production of extracellular matrix proteins, fibronectin and collagen type I, which is crucial for fibrosis after ischemic stroke. Immunohistochemistry demonstrated induction of PDGFRβ expression in vascular cells of peri-infarct areas at 3-7days in a mouse stroke model. The PDGFRβ-expressing cells extended from peri-infarct areas toward the ischemic core after day 7 while expressing fibronectin and collagen type I in the infarct areas. In contrast, desmin and α-smooth muscle actin, markers of pericytes, were only expressed in vascular cells. In PDGFRβ heterozygous knockout mice, the expression of fibronectin and collagen type I was attenuated at both mRNA and protein levels with an enlargement of the infarct volume after ischemic stroke compared with that in wild-type littermates. In cultured brain pericytes, the expression of PDGF-B, PDGFRβ, fibronectin, and collagen type I, but not desmin, was significantly increased by serum depletion (SD). The SD-induced upregulation of fibronectin and collagen type I was suppressed by SU11652, an inhibitor of PDGFRβ, while PDGF-B further increased the SD-induced upregulation. In conclusion, the expression level of PDGFRβ may be a crucial determinant of fibrosis after ischemic stroke. Moreover, PDGFRβ signaling participates in the production of fibronectin and collagen type I after ischemic stroke., (Copyright © 2014 Elsevier Inc. All rights reserved.)

We herein report the finding of a 62-year-old male, who developed dysarthria and dysphagia, with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy- (CADASIL-) like cerebral lesions. He also suffered from slowly progressive renal failure with the findings of granular deposits similar to electron-dense granular osmiophilic material in the renal arterioles. We found a novel heterozygous missense mutation of the NOTCH3 gene, c.4039G>C in exon 24, resulting in a p.Gly1347Arg substitution in its extracellular domain. The noncysteine substitution may underlie the pathogenesis of white matter lesions in the brain and of the chronic renal failure in the present case.

Objective: Thiazide diuretics are reported to have antioxidant effects and reduce pulse pressure (PP). The aim of this study was to elucidate whether hydrochlorothiazide additionally exerts such effects in stroke patients under treatment with losartan., Methods: This study was an open-label, randomized, multicenter study. Patients with a history of chronic stroke and treatment with angiotensin receptor blockers or angiotensin-converting enzyme inhibitors for essential hypertension were enrolled. Fifty-five hypertensive patients were randomly assigned to two groups: those further treated with hydrochlorothiazide and those further treated with non-diuretic antihypertensive drugs., Results: Both groups showed a significant decrease in PP over six months (hydrochlorothiazide group: 67±12 mmHg to 58±12, p<0.001; non-diuretic group: 72±12 to 61±12, p<0.001), although no significant differences were observed between the two groups. The malondialdehyde-modified low-density lipoprotein levels did not change significantly after treatment in either group., Conclusion: In this study, hydrochlorothiazide treatment did not provide any additional benefits over non-diuretic antihypertensive drugs in terms of antioxidant effects or reducing PP.

Vascular endothelial cells (ECs) are responsible for post-ischemic angiogenesis, a process that is regulated by reactive oxygen species. Recent studies indicate that endothelial Nox4 based NADPH oxidase may have a key role. This study examines the role of endothelial Nox4 in ischemia-induced angiogenesis and explores the potential mechanisms involved. Mouse lines overexpressing human Nox4 wild type (EWT) or its dominant negative form P437H (EDN) specifically in the endothelium were used. Non-transgenic littermate mice (NTg) were used as controls. Following hind limb ischemia, blood flow recovery was enhanced in EWT and was impaired in EDN compared with NTg. The critical angiogenesis regulating genes vascular endothelial growth factor receptor2 (VEGFR2), endothelial nitric oxide synthase (eNOS) and transforming growth factor beta1 (TGFbeta1) were upregulated in EWT both in the ischemic muscle and in heart ECs, while TGFbeta1 was downregulated in EDNECs. In EC, both VEGFA and TGFbeta1 stimulated EC proliferation, migration, and capillary-like network formation in EWT but failed to do so in EDN. Application of TGFbeta1 increased both VEGFR2 and eNOS expression levels,whereas blocking TGFbeta1 or addition of catalase inhibited the phosphorylation of VEGFR2 and eNOS, indicating H2O2 and TGFbeta1 signaling downstream of Nox4 is critical to maintain EC angiogenic functions. Use of cell specific transgenic mice with both upregulation and downregulation of endothelial Nox4 indicate several mechanisms linked to Nox4 play a role in angiogenesis. Endothelial Nox4 regulates ischemia-induced angiogenesis, likely through H2O2- and TGFbeta1-mediated activation of cell signaling pathways essential for endothelial function.

Objectives: The benefit of intravenous recombinant tissue plasminogen activator (rt-PA) therapy for very old patients with acute ischemic stroke remains unclear. The aim of this study was to elucidate the efficacy and safety of intravenous rt-PA therapy for patients over 80 years old., Methods: Of 13,521 stroke patients registered in the Fukuoka Stroke Registry in Japan from June 1999 to February 2013, 953 ischemic stroke patients who were over 80 years old, hospitalized within 3 h of onset, and not treated with endovascular therapy were included in this study. Among them, 153 patients were treated with intravenous rt-PA (0.6 mg/kg). For propensity score (PS)-matched case-control analysis, 148 patients treated with rt-PA and 148 PS-matched patients without rt-PA therapy were selected by 1:1 matching with propensity for using rt-PA. Clinical outcomes were neurological improvement, good functional outcome at discharge, in-hospital mortality, and hemorrhagic complications (any intracranial hemorrhage [ICH], symptomatic ICH, and gastrointestinal bleeding)., Results: In the full cohort of 953 patients, rt-PA use was associated positively with neurological improvement and good functional outcome, and negatively with in-hospital mortality after adjustment for multiple confounding factors. In PS-matched case-control analysis, patients treated with rt-PA were still at lower risk for unfavorable clinical outcomes than non-treated patients (neurological improvement, odds ratio 2.67, 95% confidence interval 1.61-4.40; good functional outcome, odds ratio 2.23, 95% confidence interval 1.16-4.29; in-hospital mortality, odds ratio 0.30, 95% confidence interval 0.13-0.65). There was no significant association between rt-PA use and risk of hemorrhagic complications in the full and PS-matched cohorts., Conclusions: Intravenous rt-PA therapy was associated with improved clinical outcomes without significant increase in risk of hemorrhagic complications in very old patients (aged>80 years) with acute ischemic stroke.

Aim: The present study aimed to determine the efficacy and safety of thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA) therapy in older patients compared with younger patients., Methods: Using the Fukuoka Stroke Registry, a prospective multicenter study for acute stroke in Japan, we analyzed data of 401 patients with acute ischemic stroke (aged 74.5 ± 13.1 years) treated with thrombolytic therapy using rt-PA. Patients were categorized into two groups according to age: those aged ≥ 75 years (n=240) and <75 years (n=161). Neurological improvement was defined as a decrease in the National Institute of Health Stroke Scale (NIHSS) score of ≥ 4 during hospitalization or an NIHSS score of 0 at discharge. Good functional outcome was defined as a modified Rankin scale score of 0-2 at 3 months after onset., Results: Neurological symptoms at admission were more severe in older patients than in younger patients. Old age (≥ 75 years) was not associated with neurological deterioration (multivariate-adjusted odds ratio [OR] 0.90, 95% confidence interval [CI] 0.46-1.77), neurological improvement (multivariate-adjusted OR 0.91, 95% CI 0.54-1.53) and symptomatic intracranial hemorrhage (multivariate-adjusted OR 1.11, 95% CI 0.19-8.87). Old age was negatively associated with good functional outcome (multivariate-adjusted OR 0.29, 95% CI 0.16-0.52) and positively associated with in-hospital mortality (multivariate-adjusted OR 19.3, 95% CI 2.4-474.9)., Conclusions: In patients treated with rt-PA, old age is associated with poor functional outcome and in-hospital mortality. However, the probability of neurological improvement and symptomatic intracranial hemorrhage in older patients is comparable with that in younger patients., (© 2013 Japan Geriatrics Society.)

Objective: Although adiponectin is a major adipocytokine that affects the pathogenesis of various cardiovascular diseases, its clinical significance in stroke remains controversial. We investigated the clinical significance of plasma adiponectin for the diagnosis, neurological severity and functional outcomes of patients with ischemic stroke., Methods: We prospectively enrolled 171 patients with ischemic stroke and 171 age- and sex-matched healthy controls. Blood samples and clinical information were obtained at day 0, 3, 7, 14 and 90 after stroke onset., Results: Average adiponectin values at day 0 did not significantly differ between the controls and the patients, but were significantly lower and higher in patients with atherothrombotic brain (ATBI) (p=0.047) and cardioembolic (CE) (p=0.008) infarction, respectively, than in the controls. Multivariate logistic regression analyses showed that the adiponectin value at day 0 could predict ATBI (odds ratio, 0.75; 95% confidence interval, 0.58 to 0.91, p=0.009, per 1-μg/mL increase). Adiponectin values at day 0 were positively associated with neurological severity as evaluated by the National Institute of Health Stroke Scale upon admission (r=0.420, p=0.003) and were higher in the groups with poor outcomes (modified Rankin Scale (mRS) ≥ 3 on day 90) than in those with good ones (mRS ≤ 2) in all stroke subtypes, with statistical significance in ATBI (p=0.015)., Conclusions: Plasma adiponectin values may help to classify stroke subtypes and predict neurological severity and functional outcome in ischemic stroke patients., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: Gastrointestinal (GI) hemorrhage is a potentially serious complication of acute stroke, but its incidence appears to be decreasing. The aim of this study was to elucidate the etiology of GI bleeding and its impact on clinical outcomes in patients with acute ischemic stroke in recent years., Methods: Using the database of the Fukuoka Stroke Registry, 6,529 patients with acute ischemic stroke registered between June 2007 and December 2012 were included in this study. We recorded clinical data including any previous history of peptic ulcer, prestroke drug history including the use of antiplatelets, anticoagulants, steroids and nonsteroidal anti-inflammatory drugs (NSAIDs), and poststroke treatment with suppressing gastric acidity. GI bleeding was defined as any episode of hematemesis or melena on admission or during hospitalization. The cause and origin of bleeding were diagnosed endoscopically. Logistic regression analysis was used to identify risk factors for GI bleeding and its influence on deteriorating neurologic function, death, and poor outcome., Results: GI bleeding occurred in 89 patients (1.4%) under the condition that 66% of the total patients received acid-suppressing agents after admission. Multivariate analysis revealed that GI bleeding was associated with the absence of dyslipidemia (p = 0.03), a previous history of peptic ulcer (p < 0.001), and the severity of baseline neurologic deficit (p = 0.002) but not with antiplatelet drugs, anticoagulants, and NSAIDs. The source was the upper GI tract in 51% of the cases; causes included peptic ulceration (28%) and malignancies (12%), and other or unidentified causes accounted for 60%. GI bleeding mostly occurred within 1 week after stroke onset. Hemoglobin concentration fell by a median value of 2.5 g/dl in patients with GI bleeding. Among them, 28 patients underwent blood transfusion (31.5%). After adjustment for confounding factors, GI bleeding was independently associated with neurologic deterioration (OR 3.9, 95% CI 2.3-6.6, p < 0.001), in-hospital death (OR 6.1, 95% CI 3.1-12.1, p < 0.001), and poor outcome at 3 months (OR 6.8, 95% CI 3.7-12.7, p < 0.001). These associations were significant irrespective of whether patients underwent red blood cell transfusion., Conclusions: GI bleeding infrequently occurred in patients with acute ischemic stroke, which was mostly due to etiologies other than peptic ulcer. GI bleeding was associated with poor clinical outcomes including neurologic deterioration, in-hospital mortality, and poor functional outcome.

Background: Epidemiologic studies have elucidated that the 1425G/A single-nucleotide polymorphism (rs2230500 single-nucleotide polymorphism) in exon 9 of the protein kinase C eta (PRKCH) gene is an independent risk factor for ischemic stroke: stroke incidence is significantly higher in the subjects with AA than those with AG or GG genotype. However, its impact on stroke recurrence remains unknown. The aim of the present study was to clarify whether the polymorphism is also a risk factor for recurrent stroke in patients with acute ischemic stroke., Methods: We enrolled 2418 consecutive patients with acute and first-ever ischemic stroke and investigated the 1425G/A polymorphism of PRKCH. Patients were followed up for a median of 733 days. The association between the polymorphism and stroke recurrence was investigated using the Cox proportional hazard model., Results: In the enrolled patients, the GG genotype was the most prevalent (63%), followed by AG (32%) and AA genotypes (5%). Recurrent stroke occurred in 302 patients during the follow-up period. Kaplan-Meier analyses revealed no difference in the rate of recurrent stroke after first-ever stroke among the 3 genotypes. The incidence of recurrent stroke was not significantly different in patients with AA (hazard ratio [HR] 1.02, 95% confidence interval .59-1.64, P=.94) or AG (HR .89, 95% confidence interval .69-1.14, P=.36) genotypes compared with those with the GG genotype after adjusting for multiple confounders., Conclusions: The 1425G/A polymorphism in PRKCH is not a significant predictor of stroke recurrence in patients with acute ischemic stroke during a 2-year follow-up period., (Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Objective: We aimed to evaluate the influence of prestroke cognitive impairment (PSCI) on outcomes in stroke patients treated with IV recombinant tissue plasminogen activator (rtPA)., Methods: OPHELIE-COG was a prospective observational multicenter study conducted in French and Japanese patients treated with IV rtPA for cerebral ischemia. The preexisting cognitive status was evaluated by the short version of the Informant Questionnaire on Cognitive Decline in the Elderly. PSCI was defined as a mean score >3. The primary endpoint was a favorable outcome (modified Rankin Scale [mRS] score 0-1) after 3 months. Secondary endpoints were symptomatic intracerebral hemorrhage (sICH), mRS scores 0-2, and mortality at 3 months. We performed a pooled analysis with Biostroke and Strokdem., Results: Of 205 patients, 62 (30.2%) met criteria for PSCI. They were 11 years older (p < 0.001). Although they had more sICH and were less frequently independent after 3 months, they did not differ for any endpoint after adjustment for age, baseline NIH Stroke Scale score, and onset-to-needle time: sICH (odds ratio [OR] 2.78; 95% confidence interval [CI] 0.65-11.86), mRS 0-1 (OR 0.82; 95% CI 0.41-1.65), mRS 0-2 (OR 0.62; 95% CI 0.28-1.37), death (OR 0.40; 95% CI 0.08-2.03). The pooled analysis found no association of PSCI with any endpoint., Conclusions: Ischemic stroke patients with PSCI should receive rtPA if they are eligible. This conclusion cannot be extended to severe cognitive impairment or severe strokes., Classification of Evidence: This study provides Class IV evidence that in patients with PSCI presenting with acute ischemic stroke, IV rtPA improves outcomes., (© 2014 American Academy of Neurology.)

Background: Ischemic stroke is accompanied by an inflammatory response, which exacerbates brain injury and deteriorates functional outcome. S100A12 is expressed abundantly in granulocytes, and has been implicated to play an important role on inflammatory reactions in various disease states. We aimed to determine the association between plasma S100A12 levels and a functional outcome in patients with acute ischemic stroke., Methods: We prospectively included 171 patients with acute ischemic stroke within 24h after onset in this study. Plasma samples were collected for the measurement of S100A12 levels. Poor functional outcome was defined as a modified Rankin Scale of 2-6 at day 90 after stroke onset., Results: Of 171 patients, 74 (43.3%) had a poor functional outcome at day 90 after stroke onset. Plasma S100A12 levels on admission were significantly higher in patients with a poor functional outcome (2.1 [1.2-5.1] ng/mL, median [interquartile]) than in those with a favorable outcome (1.1 [0.5-2.0] ng/mL; p<0.001). Multivariate analysis showed that the highest quartile of plasma S100A12 levels on admission showed a significantly higher risk for a poor functional outcome (odds ratio, 4.01; 95% confidence interval, 1.09-16.10; p=0.03) than the lowest quartile., Conclusions: High plasma S100A12 levels on admission are associated with a poor functional outcome in patients with acute ischemic stroke., (Copyright © 2014 Elsevier B.V. All rights reserved.)

5'-AMP-activated protein kinase (AMPK) is a key regulator of metabolism and survival during energy stress. Dysregulation of AMPK is strongly associated with oxidative-stress-related disease. However, whether and how AMPK is regulated by intracellular redox status remains unknown. Here we show that the activity of AMPK is negatively regulated by oxidation of Cys130 and Cys174 in its α subunit, which interferes with the interaction between AMPK and AMPK kinases (AMPKK). Reduction of Cys130/Cys174 is essential for activation of AMPK during energy starvation. Thioredoxin1 (Trx1), an important reducing enzyme that cleaves disulfides in proteins, prevents AMPK oxidation, serving as an essential cofactor for AMPK activation. High-fat diet consumption downregulates Trx1 and induces AMPK oxidation, which enhances cardiomyocyte death during myocardial ischemia. Thus, Trx1 modulates activation of the cardioprotective AMPK pathway during ischemia, functionally linking oxidative stress and metabolism in the heart., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background and Purpose: Several risk scores have been developed to predict the stroke risk after transient ischemic attack (TIA). However, the validation of these scores in different cohorts is still limited. The objective of this study was to elucidate whether these scores were able to predict short-term and long-term risks of stroke in patients with TIA., Methods: From the Fukuoka Stroke Registry, 693 patients with TIA were followed up for 3 years. Multivariable-adjusted Cox proportional hazards model was used to assess the hazard ratio of risk factors for stroke. The discriminatory ability of each risk score for incident stroke was estimated by using C-statistics and continuous net reclassification improvement., Results: The multivariable-adjusted Cox proportional hazards model revealed that dual TIA and carotid stenosis were both significant predictors for stroke after TIA, whereas abnormal diffusion-weighted image was not. ABCD3 (C-statistics 0.61) and ABCD3-I (C-statistics 0.66) scores improved the short-term predictive ability for stroke (at 7 days) compared with the ABCD2 score (C-statistics 0.54). Addition of intracranial arterial stenosis (at 3 years, continuous net reclassification improvement 30.5%; P<0.01) and exclusion of abnormal diffusion-weighted imaging (at 3 years, continuous net reclassification improvement 24.0%; P<0.05) further improved the predictive ability for stroke risk until 3 years after TIA., Conclusions: The present study demonstrates that ABCD3 and ABCD3-I scores are superior to the ABCD2 score for the prediction of subsequent stroke in patients with TIA. Addition of neuroimaging in the ABCD3 score may enable prediction of long-term stroke risk after TIA.

Background: Pericytes are multifunctional cells surrounding capillaries and postcapillary venules. In brain microvasculature, pericytes play a pivotal role under physiological and pathological conditions by producing reactive oxygen species (ROS). The aims of this study were to elucidate the source of ROS and its regulation in human brain pericytes., Methods: The expression of Nox enzymes in the cells was evaluated using RT-PCR and western blot. Superoxide production was determined by superoxide dismutase-inhibitable chemiluminescence. Silencing of Nox4 was performed using RNAi, and cell proliferation was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay., Results: Nox4 was predominant among the Nox family in human brain pericytes. Membrane fractions of cells produced superoxide in the presence of NAD(P)H. Superoxide production was almost abolished with diphenileneiodonium, a Nox inhibitor; however, inhibitors of other possible superoxide-producing enzymes had no effect on NAD(P)H-dependent superoxide production. Pericytes expressed angiotensin II (Ang II) receptors, and Ang II upregulated Nox4 expression. Hypoxic conditions also increased the Nox4 expression. Silencing of Nox4 significantly reduced ROS production and attenuated cell proliferation., Conclusion: Our study showed that Nox4 is a major superoxide-producing enzyme and that its expression is regulated by Ang II and hypoxic stress in human brain pericytes. In addition, Nox4 may promote cell growth., (© 2015 S. Karger AG, Basel.)

The relationship between the poststroke blood pressure (BP) and functional outcomes in patients with acute ischemic stroke is still controversial. The aim of the present study was to elucidate the impact of the poststroke BP on the clinical outcomes of acute ischemic stroke. Among the patients in the Fukuoka Stroke Registry, 1874 patients with first-ever acute ischemic stroke (within 24 hours of onset) who had been functionally independent before onset were prospectively enrolled in the present study. The poststroke BP levels were defined as the average values during the 48 hours after onset. The study outcomes were a good neurological recovery, neurological deterioration, and a poor functional outcome. The higher poststroke BP levels were significantly associated with a lower probability of a good neurological recovery and elevated risks of neurological deterioration and a poor functional outcome after adjusting for potential confounding factors. The multivariate-adjusted odds ratios (95% confidence interval) in the highest quintile of systolic BP (versus the lowest quintile as a reference) were 0.51 (0.37-0.71) for a good neurological recovery, 1.92 (1.15-3.27) for neurological deterioration, and 2.51 (1.69-3.74) for a poor functional outcome. Similar associations were observed when we applied the poststroke diastolic BP or pulse pressure. No evidence of the J-curve phenomenon was observed for each association. These results suggest that a high poststroke BP was significantly associated with unfavorable clinical outcomes in patients with acute ischemic stroke. There was no evidence of the J-curve phenomenon between the poststroke BP levels and the clinical outcomes.

A 73-year-old man was admitted to our hospital because of a decrease in spontaneity. His medical history included two stroke episodes, probably related to hypertension. Brain MRI on admission demonstrated acute infarction in the right caudate nucleus and left putamen. Intravenous infusion of a low molecular-weight heparin added to oral antiplatelets was started. Following admission, he developed a low grade fever and severe inflammatory reaction. The focus of infection was not evident, and none of the antibiotics tried were effective. Ten days after admission, he developed right hemiparesis, and an additional brain MRI showed new multiple infarctions. We also determined the presence of a high MPO-ANCA titer (57 EU), and we diagnosed the patient's condition to be ANCA-associated vasculitis (AAV). Steroid therapy improved his inflammatory reaction and stroke recurrence was not observed. We suggest that vasculitis should be considered as a potential risk factor for repeated small infarctions with fever of unknown origin, especially those of perforating artery territories.

Background: The incidence of intracranial bleeding during dabigatran treatment is lower than that during warfarin treatment. The characteristics of intracranial hemorrhage during dabigatran therapy, however, remain unclear., Methods and Results: The clinical data and treatment summaries of 9 intracranial bleeds that developed during dabigatran treatment in 8 patients with non-valvular atrial fibrillation were retrospectively reviewed. Five patients had small-moderate subdural hematomas, 2 had intracerebral hemorrhage and 1 had traumatic subarachnoid and parenchymal hemorrhage associated with cerebral contusion. Activated partial thromboplastin time upon admission ranged from 31.6 to 72.4s. After admission, systolic blood pressure in the 2 patients with intracerebral hemorrhage was maintained below 140 mmHg, and the subdural hematomas in 4 patients were surgically treated. None of the hematomas became enlarged and outcome was good in most cases., Conclusions: Hematomas that arise due to acute intracranial bleeding during dabigatran treatment seem to remain small to moderate, hard to expand, and manageable.

A 60-year-old man was admitted to our hospital complaining of fever, headache and vertigo. Neurological examination on admission showed mild ataxic gait. Brain magnetic resonance imaging showed linear high intensity in the left parietal lobe on diffusion-weighted imaging (DWI) and laboratory data revealed elevated serum lactate dehydrogenase and soluble interleukin-2 receptor. Although intravascular lymphoma was suspected from these findings, bone marrow and skin biopsies were negative. Two months later, he presented with sensory disturbance of the left upper limb, and new lesions in the right frontal and bilateral parietal lobes were detected on DWI. A systemic evaluation showed multiple low-density lesions in the bilateral kidneys on computed tomography. Based on the results of a renal biopsy, we made a histological diagnosis of intravascular large B-cell lymphoma (IVLBCL). As IVLBCL is quite rare and often has a poor prognosis, a systemic evaluation to determine the proper biopsy site is needed for early diagnosis.

Background and Purpose: The findings of recent clinical trials suggest that treatment with high-dose statins reduces the risk of stroke recurrence. However, the doses approved in Japan are much lower than those in the previous studies. This study aimed to elucidate whether prescribed doses of statins reduce the risks of cerebrovascular events (CVEs: stroke recurrence or transient ischemic attack) and all-cause mortality in a cohort of Japanese patients with first-ever ischemic stroke., Methods: The 2822 eligible patients registered in the Fukuoka Stroke Registry with first-ever acute ischemic stroke from June 2007 to February 2011 were classified into statin users (n = 993) and non-users (n = 1829) at discharge, and followed up until March 2012. We assessed the cumulative risks of CVE and all-cause mortality by the Kaplan-Meier method, and calculated hazard ratios (HRs) and 95% confidential intervals (CIs) using the Cox proportional hazards model., Results: During the follow-up time (median, 2.0 years), 305 patients had CVEs and 345 died. The cumulative risks of CVE and death after 4 years were significantly lower in statin users than in non-users (13.8% versus 19.5%, P = 0.005 for CVE; 11.8% versus 21.7%, P < 0.001 for death). After adjusting for multiple confounding factors, statin treatment significantly reduced the risks of CVE (HR, 0.70; 95% CI, 0.53 to 0.92; P = 0.011) and all-cause mortality (HR, 0.67; 95% CI, 0.50 to 0.89; P = 0.006)., Conclusions: Our findings suggest that low-dose statin may reduce the risks of CVE and death in Japanese patients with acute ischemic stroke., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Objectives: We investigated the clinical characteristics of patients with stroke recurrence in the first year after cardioembolic stroke, and determined the predictors associated with recurrence., Design: A prospective cohort study., Setting: Multicentre study at the Fukuoka prefecture in Japan., Participants: We enroled 2084 consecutive patients who were hospitalised in stroke centres within 7 days of onset from June 2007 to October 2009. The clinical characteristics of patients were assessed on admission, and the clinical course of all patients was followed for 1 year., Results: Of all patients, 425 (234 men, 76±11 years of age) had cardioembolic stroke and were included in this study. Fifty-one patients (12%) suffered a recurrence during the follow-up period. Age (HR 1.04, 95% CI 1.01 to 1.06, p=0.014), and level of C reactive protein (HR 1.01, 95% CI 1.00 to 1.02, p=0.018) on admission were significantly associated with recurrence in the univariate analyses. Male gender (HR 0.61, 95% CI 0.35 to 1.05, p=0.076), body mass index (HR 0.94, 95% CI 0.87 to 1.01, p=0.093), hypertension (HR 0.59, 95% CI 0.33 to 1.06, p=0.079), diastolic blood pressure (HR 0.99, 95% CI 0.97 to 1.00, p=0.087) and haematocrit (HR 0.95, 95% CI 0.91 to 1.00, p=0.052) were marginally significant in the univariate Cox analyses. Multivariate Cox proportional hazards analysis showed that age (HR 1.03, 95% CI 1.00 to 1.06, p=0.031, per 1-year increase), and C reactive protein (HR 1.01, 95% CI 1.00 to 1.02, p=0.022, per 1 mg/L increase) were independent predictors of a recurrence in the first year after cardioembolic stroke., Conclusions: In patients with cardioembolic ischaemic stroke, age and C reactive protein are independent risk factors for recurrence in the first year after onset.

Background and Purpose: The relationship between the intensity of anticoagulation at the onset of acute cardioembolic stroke and clinical outcome after stroke is unclear. Here, we elucidated the relationship between prothrombin time-international normalized ratio (PT-INR) values on admission and clinical outcomes in patients with acute cardioembolic stroke., Methods: A total of 602 patients from the Fukuoka Stroke Registry in Japan who had been treated with warfarin but developed cardioembolic stroke were enrolled. The patients were classified into 3 groups according to their PT-INR values on admission: PT-INR <1.50, 411 patients; PT-INR 1.50 to 1.99, 146 patients; and PT-INR ≥2.00, 45 patients. The associations between PT-INR categories and severe neurological deficits (National Institutes of Health Stroke Scale ≥10) on admission and poor functional outcome (modified Rankin scale 4-6) at discharge were investigated using a logistic regression analysis., Results: Neurological deficits on admission were less severe, and functional outcome at discharge was more favorable as the PT-INR level on admission increased. The multivariate analysis revealed that severe neurological deficits were inversely associated with PT-INR on admission (PT-INR 1.50-1.99: odds ratio, 0.66; 95% confidence interval, 0.43-1.00; PT-INR ≥2.00: odds ratio, 0.41; 95% confidence interval, 0.20-0.83; compared with a reference group of PT-INR <1.50). Poor functional outcome was less likely in patients with PT-INR ≥2.00 (odds ratio, 0.20; 95% confidence interval, 0.06-0.55) after adjustment for confounders., Conclusions: Prestroke PT-INR ≥2.0 is associated with favorable clinical outcomes after acute cardioembolic stroke.

Regulated upon Activation, Normal T-cell Expressed, and Secreted (RANTES) is a well-known pro-inflammatory chemokine and its role in ischemic stroke remains controversial. We examined the significance of RANTES in ischemic stroke and aimed to elucidate the direct effect of RANTES on neurons. Plasma concentrations of major C-C chemokines, including RANTES, and neurotrophic factors were examined in 171 ischemic stroke patients and age- and gender- matched healthy subjects. Plasma concentrations of RANTES at day 0 after onset were significantly elevated in stroke patients, compared with controls, and were highly correlated with those of BDNF, EGF, and VEGF. In a mouse middle cerebral artery occlusion model (MCAO), plasma RANTES was significantly elevated and the expression of RANTES was markedly upregulated in neurons particularly in peri-infarct areas. The expression of CCR3 and CCR5, receptors for RANTES, was also induced in neurons, while another receptor, CCR1, was observed in vascular cells, in peri-infarct areas after MCAO. We examined the effects of RANTES on differentiated PC12 cells, a model of neuronal cells. Treatment with RANTES induced the activation of Akt and Erk1/2, and attenuated the cleavage of caspase-3 in the cells. RANTES increased the expression of BDNF, EGF, and VEGF in the cells. Moreover, RANTES maintained the number of cells under serum free conditions. The RANTES-mediated upregulation of neurotrophic factors and cell survival were significantly attenuated by the inhibition of Akt or Erk1/2. Taken together, RANTES is an interesting chemokine that is produced from neurons after ischemic stroke and has the potential to protect neurons directly or indirectly through the production of neurotrophic factors in peri-infarct areas., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Rationale: NADPH oxidase (Nox) 2 and Nox4 are major components of the Nox family which purposefully produce reactive oxidative species, namely O2(-) and H2O2, in the heart. The isoform-specific contribution of Nox2 and Nox4 to ischemia/reperfusion (I/R) injury is poorly understood., Objective: We investigated the role of Nox2 and Nox4 in mediating oxidative stress and myocardial injury during I/R using loss-of-function mouse models., Methods and Results: Systemic (s) Nox2 knockout (KO), sNox4 KO, and cardiac-specific (c) Nox4 KO mice were subjected to I/R (30 minutes/24 hours, respectively). Both myocardial infarct size/area at risk and O2(-) production were lower in sNox2 KO, sNox4 KO, and cNox4 KO than in wild-type mice. Unexpectedly, however, the myocardial infarct size/area at risk was greater, despite less O2(-) production, in sNox2 KO+cNox4 KO (double-KO) mice and transgenic mice (Tg) with cardiac-specific expression of dominant-negative Nox, which suppresses both Nox2 and Nox4, than in wild-type or single KO mice. Hypoxia-inducible factor-1α was downregulated whereas peroxisome proliferator-activated receptor-α was upregulated in Tg-dominant-negative Nox mice. A cross with mice deficient in prolyl hydroxylase 2, which hydroxylates hypoxia-inducible factor-1α, rescued the I/R injury and prevented upregulation of peroxisome proliferator-activated receptor-α in Tg-dominant-negative Nox mice. A cross with peroxisome proliferator-activated receptor-α KO mice also attenuated the injury in Tg- dominant-negative Nox mice., Conclusions: Both Nox2 and Nox4 contribute to the increase in reactive oxidative species and injury by I/R. However, low levels of reactive oxidative species produced by either Nox2 or Nox4 regulate hypoxia-inducible factor-1α and peroxisome proliferator-activated receptor-α, thereby protecting the heart against I/R, suggesting that Noxs also act as a physiological sensor for myocardial adaptation.

Background: Vascular endothelial growth factor (VEGF) is a well-known molecule mediating neuronal survival and angiogenesis. However, its clinical significance in ischemic stroke is still controversial. The goal of this study was to examine the temporal profile of plasma VEGF value and its clinical significance in ischemic stroke with taking its subtypes into consideration., Methods: We prospectively enrolled 171 patients with ischemic stroke and age- and gender-matched healthy subjects. The stroke patients were divided into 4 subtypes: atherothrombotic infarction (ATBI, n = 34), lacunar infarction (LAC, n = 45), cardioembolic infarction (CE, n = 49) and other types (OT, n = 43). Plasma VEGF values were measured as a part of multiplex immunoassay (Human MAP v1.6) and we obtained clinical information at 5 time points (days 0, 3, 7, 14 and 90) after the stroke onset., Results: Plasma VEGF values were significantly higher in all stroke subtypes but OT than those in the controls throughout 90 days after stroke onset. There was no significant difference in the average VEGF values among ATBI, LAC, and CE. VEGF values were positively associated with neurological severity in CE patients, while a negative association was found in ATBI patients. After adjustment for possible confounding factors, plasma VEGF value was an independent predictor of poor functional outcome in CE patients., Conclusions: Although plasma VEGF value increases immediately after the stroke onset equally in all stroke subtypes, its significance in functional outcome may be different among the stroke subtypes.

Rationale: Oxidation of cysteine residues in class II histone deacetylases (HDACs), including HDAC4, causes nuclear exit, thereby inducing cardiac hypertrophy. The cellular source of reactive oxygen species responsible for oxidation of HDAC4 remains unknown., Objective: We investigated whether nicotinamide adenine dinucleotide phosphate oxidase 4 (Nox4), a major nicotinamide adenine dinucleotide phosphate oxidase, mediates cysteine oxidation of HDAC4., Methods and Results: Phenylephrine (100 μmol/L), an α1 adrenergic agonist, induced upregulation of Nox4 (1.5-fold; P<0.05) within 5 minutes, accompanied by increases in O(2)(-) (3.5-fold; P<0.01) from the nuclear membrane and nuclear exit of HDAC4 in cardiomyocytes. Knockdown of Nox4, but not Nox2, attenuated O(2)(-) production in the nucleus and prevented phenylephrine-induced oxidation and nuclear exit of HDAC4. After continuous infusion of phenylephrine (20 mg/kg per day) for 14 days, wild-type and cardiac-specific Nox4 knockout mice exhibited similar aortic pressures. Left ventricular weight/tibial length (5.7±0.2 versus 6.4±0.2 mg/mm; P<0.05) and cardiomyocytes cross-sectional area (223±13 versus 258±12 μm(2); P<0.05) were significantly smaller in cardiac-specific Nox4 knockout than in wild-type mice. Nuclear O(2)(-)production in the heart was significantly lower in cardiac-specific Nox4 knockout than in wild-type mice (4116±314 versus 7057±1710 relative light unit; P<0.05), and cysteine oxidation of HDAC4 was decreased. HDAC4 oxidation and cardiac hypertrophy were also attenuated in cardiac-specific Nox4 knockout mice 2 weeks after transverse aortic constriction., Conclusions: Nox4 plays an essential role in mediating cysteine oxidation and nuclear exit of HDAC4, thereby mediating cardiac hypertrophy in response to phenylephrine and pressure overload.

Objective: We have previously shown that Na(+)/H(+) exchanger isoform 1 (NHE1) plays an important role in Ca(2+) signaling and cell proliferation in human central nervous system (CNS) pericytes. The aims of the present study were to elucidate how NHE1-induced Ca(2+) signaling during acidosis is transformed into cellular responses in CNS pericytes., Methods and Results: Human CNS pericytes were cultured, and the activation of cAMP responsive element-binding protein (CREB) was evaluated by Western blotting analysis, immunofluorescence, and luciferase assays. In human CNS pericytes, low extracellular Na(+) or low pH generated Ca(2+) oscillation and subsequently phosphorylated Ca(2+)/calmodulin-dependent kinase II (CaMKII) and CREB in a time-dependent manner. Focal cerebral ischemia was applied using photothrombotic distal middle cerebral artery occlusion in mice, and the phosphorylation of CREB and the production of interleukin-6 were observed in pericytes migrating into the peri-infarct penumbra during the early phase after ischemic insult., Conclusions: Our results indicate that extracellular acidosis induces Ca(2+) oscillation via NHE1, leading to Ca(2+)/CaMKII-dependent CREB activation in human CNS pericytes. Acidosis may upregulate a variety of proteins, such as interleukin-6, through the NHE1-Ca2+/CaMKII-CREB pathway in brain pericytes and may thus modulate brain ischemic insult.

Post-ischemic inflammation is an essential step in the progression of ischemic stroke. This review focuses on the function of infiltrating immune cells, macrophages, and T cells, in ischemic brain injury. The brain is a sterile organ; however, the activation of Toll-like receptor (TLR) 2 and TLR4 is pivotal in the beginning of post-ischemic inflammation. Some endogenous TLR ligands are released from injured brain cells, including high mobility group box 1 and peroxiredoxin family proteins, and activate the infiltrating macrophages and induce the expression of inflammatory cytokines. Following this step, T cells also infiltrate into the ischemic brain and mediate post-ischemic inflammation in the delayed phase. Various cytokines from helper T cells and γδT cells function as neurotoxic (IL-23/IL-17, IFN-γ) or neuroprotective (IL-10, IL-4) mediators. Novel neuroprotective strategies should therefore be developed through more detailed understanding of this process and the regulation of post-ischemic inflammation., (© 2012 The Authors Journal of Neurochemistry © International Society for Neurochemistry.)

Background and Purpose: Particulate matter is increasingly recognized as a cause of human diseases, including cardiovascular diseases. However, the association between Asian dust (AD), a windblown sand dust originating from mineral soil in the deserts of China and Mongolia, and the incidence of cardiovascular diseases is unclear. The aim of the present study was to elucidate whether AD is associated with the incidence of ischemic stroke., Methods: This study investigated the onset time of 7429 consecutive patients with ischemic stroke who were admitted to seven stroke centers in Fukuoka, Japan, between June 1999 and March 2010. Meteorologic variables and air pollutants, including AD and suspended particulate matters, were investigated during the identical period. A time-stratified case-crossover study was conducted to assess the association between AD and stroke incidence using a conditional logistic regression analysis., Results: Although AD was not significantly associated with the overall incidence of ischemic stroke, there was a relationship specific to the stroke subtypes. AD was significantly associated with the incidence of atherothrombotic brain infarction after adjusting for expected confounders, including meteorologic variables and other air pollutants. No association was detected in other types of ischemic stroke., Conclusion: These data suggest that AD does not increase the overall incidence of ischemic stroke, but it is specifically associated with the risk of atherothrombotic brain infarction.

Background: Despite recent progress in treatments for secondary prevention, ischemic stroke recurs in 8% to 12% of stroke survivors. We investigated the predisposing factors associated with recurrence within the first 12 months after an ischemic event to explore more effective preventive strategies., Methods: Between June 2007 and April 2008, acute (within 7 days of onset) ischemic stroke patients were registered in the Fukuoka Stroke Registry (FSR), a multicenter, prospective, observational database. The clinical characteristics on admission were analyzed, and the patients were followed for 12 months., Results: Two hundred sixty patients (151 males and 109 females, 71 ± 11 years of age) were registered; 25 (9.6%) had recurrence of ischemic stroke during the follow-up period. Kaplan-Meier curve analysis revealed a significant difference in recurrence-free survival between patients with high-density lipoprotein (HDL) cholesterol <40 mg/dL on admission and those with HDL cholesterol ≥ 40 mg/dL (P = .042). Adjusted multivariate logistic regression analysis showed that age (odds ratio 1.06; 95% CI, 1.00-1.11; P = .035) and HDL cholesterol <40 mg/dL (odds ratio 2.73; 95% CI, 1.01-7.38; P = .048) on admission were independently associated with a recurrence of ischemic stroke within 12 months of the initial onset., Conclusions: Aging and low HDL cholesterol levels are considered independent risk factors for a recurrence of ischemic stroke., (Copyright © 2012 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Neurotrophins are crucial regulators of neuronal survival and death. Evidence suggests that cells comprising the neurovascular unit (NVU) cooperatively mediate neuronal development, survival and regeneration. The aim of this study was to test whether cerebrovascular cells, endothelial cells and pericytes, produce neurotrophins and play neuroprotective roles during hypoxic insults. We examined the expression of neurotrophins and their receptors in cultured human cerebral microvascular endothelial cells and pericytes, astrocytes and the rat neuronal cell line PC12. Differentiated PC12 cells expressed TrkA, the NGF receptor, which was significantly upregulated by hypoxia at 1% O(2) and regulated neuronal survival. Both pericytes and astrocytes expressed three neurotrophins, i.e. NGF, BDNF and NT-3, while TrkB and TrkC, specific receptors for BDNF and NT-3, were expressed in astrocytes, but not pericytes. In response to hypoxia, among the neurotrophins expressed in pericytes and astrocytes only NT-3 expression was significantly upregulated in pericytes. Treatment of astrocytes with NT-3 significantly activated Erk1/2 and increased the expression of NGF both at mRNA and protein levels. The MEK1 inhibitor U0126 or siRNA-mediated knockdown of TrkC abolished the NT-3-induced upregulation of NGF in astrocytes. Taken together, cerebral microvascular pericytes and astrocytes are potent producers of neurotrophins in the NVU. In response to hypoxia, pericytes increase NT-3 production, which induces astrocytes to increase NGF production through the TrkC-Erk1/2 pathway. The interplay between pericytes and astrocytes through neurotrophins in the NVU may play an important role in neuronal survival under hypoxic conditions., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Brain pericytes regulate a variety of functions, such as microcirculation, angiogenesis, and the blood brain barrier in the brain. Recent studies have also shown that they are pluripotent in a manner similar to mesenchymal stem cells. Since, brain pericytes actively control these functions, these cells probably play an important role not only during brain ischemia, but also in the post-stroke period.

Background: The prognosis in ischemic stroke is poor in diabetic patients. However, scant research has so far been done on the predisposing factors associated with poor outcomes., Methods: We prospectively investigated the background characteristics and prognosis at 3 months in 241 consecutive diabetic patients having their first ischemic stroke (153 males, 88 females, mean age ± SD, 71 ± 10 years). Poor functional outcome was defined as modified Rankin scale ≥ 3 at 3 months after onset., Results: Univariate analysis showed that age, dementia, initial National Institutes of Health Stroke Scale (NIHSS) score, systolic blood pressure on admission, proteinuria, stroke subtype, and prior use of angiotensin receptor blocker (ARB) were significantly related to an outcome at 3 months after onset. A multivariate logistic regression analysis showed that age (odds ratio (OR) 1.07, 95% confidence interval (CI) 1.01 to 1.13, p=0.017, per 1-year increase), NIHSS score (OR 1.22, 95% CI 1.12 to 1.35, p<0.001, per 1-score increase), and proteinuria (OR 4.22, 95% CI 1.71 to 10.92, p=0.002) were significantly and independently associated with poor clinical outcome after ischemic stroke in diabetic patients. Conversely, prior use of ARB (OR 0.28, 95% CI 0.09 to 0.79, p=0.023) was associated with a better outcome., Conclusions: In diabetic patients, proteinuria was independently associated with a poor clinical outcome after ischemic stroke, whereas the prior use of ARB appeared to be beneficial., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Platelet derived growth factor (PDGF)-B plays a neuroprotective role in brain damages, including ischemic stroke. It has been suggested recently that PDGF receptor β (PDGFRβ) expressed in brain pericytes as well as in neurons and astrocytes may mediate the neuroprotective role of PDGF-B. The aims of this study were to elucidate the roles of PDGFRβ signaling in brain pericytes after ischemic stroke. In a rat middle cerebral artery occlusion (MCAO) model, PDGFRβ expression was induced specifically in the pericytes in peri-infarct areas and its level was gradually increased. PDGF-B induced marked phosphorylation of Akt in cultured brain pericytes. Consistently, PDGF-B was upregulated in endothelial cells in per-infarct areas and Akt was strongly phosphorylated in the PDGFRβ-expressing pericytes in periinfarct areas after MCAO. In the cultured pericytes, PDGF-B induced cell growth and anti-apoptotic responses through Akt. Furthermore, PDGF-B significantly increased the expression of nerve growth factor (NGF) and neurotrophin-3 (NT-3) through Akt in the pericytes. Thus, the PDGFRβ-Akt signaling in brain pericytes may play various important roles leading to neuroprotection after ischemic stroke.