Higher Frequency of Premature Atrial Contractions Correlates With Atrial Fibrillation Detection after Cryptogenic Stroke.

BACKGROUND: Covert atrial fibrillation (AF) is a major cause of cryptogenic stroke. This study investigated whether a dose-dependent relationship exists between the frequency of premature atrial contractions (PACs) and AF detection in patients with cryptogenic stroke using an insertable cardiac monitor (ICM). METHODS: We enrolled consecutive patients with cryptogenic stroke who underwent ICM implantation between October 2016 and September 2020 at 8 stroke centers in Japan. Patients were divided into 3 groups according to the PAC count on 24-hour Holter ECG: ≤200 (group L), >200 to ≤500 (group M), and >500 (group H). We defined a high AF burden as above the median of the cumulative duration of AF episodes during the entire monitoring period. We evaluated the association of the frequency of PACs with AF detection using log-rank trend test and Cox proportional hazard model and with high AF burden using logistic regression model, adjusting for age, sex, CHADS2 score. RESULTS: Of 417 patients, we analyzed 381 patients with Holter ECG and ICM data. The median age was 70 (interquartile range, 59.5-76.5), 246 patients (65%) were males, and the median duration of ICM recording was 605 days (interquartile range, 397-827 days). The rate of new AF detected by ICM was higher in groups with more frequent PAC (15.5%/y in group L [n=277] versus 44.0%/y in group M [n=42] versus 71.4%/y in group H [n=62]; log-rank trend P<0.01). Compared with group L, the adjusted hazard ratios for AF detection in groups M and H were 2.11 (95% CI, 1.24-3.58) and 3.23 (95% CI, 2.07-5.04), respectively, and the adjusted odds ratio for high AF burden in groups M and H were 2.57 (95% CI, 1.14-5.74) and 4.25 (2.14-8.47), respectively. CONCLUSIONS: The frequency of PACs was dose-dependently associated with AF detection in patients with cryptogenic stroke.

C-Reactive Protein, Interleukin-6, and Vascular Recurrence After Stroke: An Individual Participant Data Meta-Analysis.

BACKGROUND: Anti-inflammatory therapies reduce recurrent vascular events in coronary disease. Existing studies have reported highly conflicting findings for the association of blood inflammatory markers with vascular recurrence after stroke leading to uncertainty about the potential of anti-inflammatory therapies after stroke and no consensus about the utility of measurement of inflammatory markers in current guidelines. METHODS: We investigated the association between hsCRP (high-sensitivity C-reactive protein), IL-6 (interluekin-6), and recurrent major adverse cardiovascular events (MACE), and stroke from individual participant data from 8420 patients with ischemic stroke/transient ischemic attack from 10 prospective studies. We did within-study multivariable regression analyses and then combined adjusted risk ratio (RR) by random-effects meta-analysis. RESULTS: During 18 920 person-years of follow-up, 1407 (16.7% [95% CI, 15.9-17.5]) patients had MACE and 1191 (14.1% [95% CI, 13.4-14.9]) patients had recurrent stroke. On bivariate analysis, baseline IL-6 was associated with MACE (RR, 1.26 [95% CI, 1.10-1.43]) and recurrent stroke (RR, 1.18 [95% CI, 1.05-1.32]), per unit increase logeIL-6. Similar associations were observed for hsCRP (MACE RR, 1.19 [95% CI, 1.09-1.29]; recurrent stroke RR, 1.12 [95% CI, 1.04-1.21], per unit increase logehsCRP). After adjustment for vascular risk factors and treatment, independent associations remained with MACE (IL-6, RR, 1.12 [95% CI, 1.04-1.21]; hsCRP, RR, 1.09 [95% CI, 1.04-1.15]) and recurrent stroke (IL-6, RR, 1.09 [95% CI, 1.00-1.19]; hsCRP, RR, 1.05 [95% CI, 1.00-1.11]). Comparing the top with the bottom quarters (Q4 versus Q1), IL-6 (RR, 1.35 [95% CI, 1.09-1.67]) and hsCRP (RR, 1.31 [95% CI, 1.07-1.61]) were associated with MACE after adjustment. Similar results were observed for recurrent stroke for IL-6 (RR, 1.33 [95% CI, 1.08-1.65]) but not hsCRP (RR, 1.16 [95% CI, 0.93-1.43]). CONCLUSIONS: Blood markers of inflammation were independently associated with vascular recurrence after stroke, strengthening the rationale for randomized trials of anti-inflammatory therapies for secondary prevention after ischemic stroke/TIA.

Baseline platelet count may predict short-term functional outcome of cerebral infarction.

BACKGROUND AND AIMS: Platelets play an important role in homeostasis however, they have also been associated with increased mortality after myocardial infarction. In the present study, we investigated whether platelet count is associated with differences in the short-term prognosis at the time of hospital discharge and early neurological deterioration in ischemic stroke patients. METHODS: Patients with ischemic stroke were enrolled from among 661 cerebrovascular disease patients admitted between January 2018 and December 2020. Patients who received hyperacute treatment, had a pre-onset modified Rankin scale (mRS) ≥ 3, transient ischemic attack, or active malignant disease were excluded. The platelet count was divided into quartiles (Q1-4) according to the number of patients, and the relationship between platelet count and prognosis was assessed using multivariable analysis. RESULTS: In total, 385 patients were included in the study. Regarding the functional outcome by platelet count, there was a significant increase in mRS ≥ 3 at discharge in the Q4 (range: 243-1327 × 109/L, p = 0.013, ORs: 1.674, 95%CI: 1.253-6.681) group compared to the Q3 (range: 205-242 × 109/L) group even after adjusting for factors with P < 0.2 in univariate analysis. Furthermore, the frequency of neurological deterioration (NIHSS ≥ 4) within 1 week was significantly lower in the Q3 group than in the Q1 (range; 19-173 × 109/L) and Q4 groups even after adjustment (Q1; p = 0.020 ORs: 6.634, 95%CI: 1.352-32.557, Q4; p = 0.007 ORs: 8.765, 95%CI: 1.827-42.035). CONCLUSION: Platelet count at onset may affect the prognosis of cerebral infarction and early neurological deterioration. This study may help clarify the pathogenesis of cerebral infarction to improve prognosis.

Association of blood eicosapentaenoic acid levels with intracerebral hemorrhage during the COVID-19 pandemic: preliminary experience from a single-center in Japan.

BACKGROUND: The COVID-19 pandemic has forced lockdowns and declarations of states of emergency, resulting in marked changes to daily life such as dietary habits in many countries. Though serum omega-3 polyunsaturated fatty acids levels have been shown to be useful markers for recurrent vascular events or worse prognosis in cardiovascular diseases and ischemic stroke, the relationship between serum omega-3 PUFA levels and the occurrence of intracerebral hemorrhage has essentially been unknown. We explored the association of serum omega-3 polyunsaturated fatty acids with intracerebral hemorrhage during the COVID-19 pandemic. METHODS: Participants comprised patients admitted to Juntendo University Hospital (Tokyo, Japan) with intracerebral hemorrhage between January 1, 2016 and April 30, 2020. Clinical characteristics including serum omega-3 polyunsaturated fatty acid levels were compared between patients developing intracerebral hemorrhage during the period from January 1, 2016 to February 29, 2020, and the subsequent COVID-19 pandemic period (March 1 to April 30, 2020). Clinical characteristics independently related to intracerebral hemorrhage during the COVID-19 pandemic were analyzed by comparing these two cohorts of intracerebral hemorrhage patients in different periods. RESULTS: A total of 103 patients (age, 67.0 ± 13.9 years; 67 males) with intracerebral hemorrhage were enrolled. Intracerebral hemorrhage developed in 91 patients before and 12 patients during the COVID-19 pandemic. Monthly averages of intracerebral hemorrhage patients admitted to our hospital during and before the COVID-19 pandemic were 6 and 1.82, respectively. Serum eicosapentaenoic acid levels were significantly lower in intracerebral hemorrhage patients during the COVID-19 pandemic than before (31.87 ± 12.93 µg/ml vs. 63.74 ± 43.29 µg/ml, p = 0.007). Multiple logistic regression analysis showed that, compared to before the COVID-19 pandemic, dyslipidemia (odds ratio 0.163, 95% confidence interval 0.031-0.852; p = 0.032) and eicosapentaenoic acid levels (odds ratio 0.947, 95% confidence interval 0.901-0.994; p = 0.029) were associated with intracerebral hemorrhage during the COVID-19 pandemic. CONCLUSIONS: From our preliminary results, low eicosapentaenoic acid levels were linked with intracerebral hemorrhage during the COVID-19 pandemic. Low levels of eicosapentaenoic acid might be an endogenous surrogate marker for intracerebral hemorrhage during the COVID-19 pandemic.

Impact of D-dimer for pathologic differentiation on transesophageal echocardiography in embolic stroke of undetermined source: a single-center experience.

BACKGROUND: Embolic stroke of undetermined source (ESUS) encompasses diverse embologenic mechanisms, which transesophageal echocardiography (TEE) is critical to detect. Specific markers related to each embolic source in ESUS is not fully studied. We focused on D-dimer levels, and explored the association of D-dimer with potential embolic sources (PES) identified on TEE in ESUS. METHODS: Consecutive patients with ESUS were included in this study. Clinical characteristics including D-dimer levels were compared between ESUS patients with and without TEE, and among none of, one, and at least two PES in ESUS patients undergoing TEE. Factors related to elevation of D-dimer were analyzed. RESULTS: A total of 211 patients (age, 69.3 ± 13.2 years; 149 males) with ESUS were enrolled. Of these, 115 received TEE, displaying significantly younger age and lower D-dimer levels than patients without TEE (P < 0.05), and 20 (17%), 61 (53%), and 34 (30%) patients were classified into none of, one, and ≥ two PES, respectively. On multiple logistic regression analysis, D-dimer levels were related to one PES (odds ratio [OR]: 9.01; 95% confidence interval [CI]: 1.00-81.51; P = 0.050) and PES ≥ two (OR: 9.76; 95% CI: 1.07-88.97; P = 0.043). Right-to-left shunt (RLS) with deep venous thrombosis (DVT)(OR: 13.94; 95% CI: 1.77-109.99; P = 0.012) and without DVT (OR: 3.90; 95% CI: 1.20-12.70; P = 0.024) were associated with elevation of D-dimer. CONCLUSIONS: D-dimer levels were higher in patients with PES. Among PES, RLS, with and without DVT, were associated with increase of D-dimer in ESUS.

Cerebral artery dissection secondary to antiphospholipid syndrome: A report of two cases and a literature review.

INTRODUCTION: Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by thromboembolic events, including ischemic stroke or complications in pregnancy, and the presence of antiphospholipid antibodies. Cervical artery dissection (CAD) is not an uncommon cause of stroke in young adults. The concomitant presence of APS and CAD is extremely rare. METHODS: Two cases with APS who developed acute ischemic strokes related to CAD are reported. A comprehensive systematic literature search using the PubMed database was also conducted. RESULTS: In Case 1, a 36-year-old woman who had been diagnosed with systemic lupus erythematosus and had been repeatedly positive for lupus anticoagulant tests developed an ischemic stroke caused by a vertebral artery dissection (VAD). After admission, she had a recurrent ischemic stroke, followed by considerable changes in steno-occlusive lesions of the vertebrobasilar artery system. In Case 2, a 36-year-old man developed multiple brain infarcts due to bilateral VAD with aneurysmal formations and associated with pulmonary embolism. The anticardiolipin antibody titer was repeatedly elevated after stroke. The literature review identified 8 patients with CAD associated with APS, involving the internal carotid artery in 6 patients and the middle cerebral artery and vertebral artery in 1 patient each. The patients were predominantly young and female, infrequently had atherosclerotic vascular risk factors, and were positive for various antiphospholipid antibodies. CONCLUSIONS: The current report described two rare cases of ischemic stroke caused by CAD secondary to APS, along with a review of the literature; the patients displayed characteristic clinical manifestations, implying specific mechanisms for cerebral artery disorders secondary to APS.

The effects of A1/A2 astrocytes on oligodendrocyte linage cells against white matter injury under prolonged cerebral hypoperfusion.

As oligodendrocyte precursor cells (OPCs) are vulnerable to ischemia, their differentiation to oligodendrocytes (OLG) is impaired in chronic cerebral hypoperfusion. Astrocyte-OLG interaction is important for white matter homeostasis. Recently, reactive astrocytes were separated into two types, A1 (cytotoxic) and A2 (neurotrophic). However, their role in prolonged cerebral hypoperfusion remains unclear. We analyzed the effects of interaction between A1-A2 astrocytes and OPC-OLG under hypoperfusion, focusing on mitochondrial migration. As an in vivo model, chronic hypoperfusion model mice were created by bilateral common carotid artery stenosis (BCAS) using microcoils. As a matching in vitro study, rat primary cells were cocultured with a nonlethal concentration of CoCl2 . At 28 days after hypoperfusion, the number of OPC and astrocytes increased, whereas that of OLG decreased. Increased astrocytes were mainly A1-like astrocytes; however, the number of A2-like type decreased. In cell culture, OPC differentiation was interrupted under mimic chronic ischemia, but improved after astrocyte-conditioned medium (ACM) was added. However, injured-ACM was unable to improve OPC maturation. Incubation with CoCl2 changed astrocytes from A2-like to A1-like, and mitochondrial migration was also reduced. A Trkß agonist was able to maintain astrocytes from A1-like to A2-like even under hyperperfused conditions, and aided in OPC maturation and memory impairment via mitochondrial migration and drug effects in cell culture study and BCAS model. The reduction of A1-like astrocytes protects against white matter injury. Trkß agonists may play an important role in the impairment under chronic ischemic conditions. Mitochondrial migration may be a broad therapeutic strategy for cerebrovascular diseases. MAIN POINTS: Prolonged cerebral hypoperfusion leads to impaired oligodendrocyte (OLG) maturation and increased numbers of A1 astrocytes. Mitochondria migration maintained A2 astrocyte morphology, mature OLG, and myelinated white matter in vivo/vitro.

Antepartum eclampsia with reversible cerebral vasoconstriction and posterior reversible encephalopathy syndromes.

A 39-year-old pregnant woman was experienced thunderclap headache due to reversible cerebral vasoconstriction syndrome (RCVS) as a prodromal symptom. Two days after, she was brought to our hospital after an eclamptic seizure at 35 weeks of gestation. After management with magnesium sulphate, a cesarean delivery was performed, and passed without eclamptic seizure recurrence with calcium channel blocker (CCB) administration for hypertension and prophylaxis of another seizure. Antepartum eclampsia is sometimes complicated by headache as a prodromal symptom. Cerebrovascular diseases in the perinatal period include eclampsia, RCVS and posterior reversible encephalopathy syndrome, which have potentially overlapping pathologies. Here, we first report a case of overlapping those three diseases in the antepartum period. Our best literature review showed that antepartum RCVS is severe and has complications besides thunderclap headache, and there is a case report which CCB administration was shown to be effective in the treatment of antepartum RCVS. If thunderclap headache is recognized, prediction of eclampsia and getting better course of RCVS with CCB administration may be possible.

Pleiotropic Effects of Exosomes as a Therapy for Stroke Recovery.

Stroke is the leading cause of disability, and stroke survivors suffer from long-term sequelae even after receiving recombinant tissue plasminogen activator therapy and endovascular intracranial thrombectomy. Increasing evidence suggests that exosomes, nano-sized extracellular membrane vesicles, enhance neurogenesis, angiogenesis, and axonal outgrowth, all the while suppressing inflammatory reactions, thereby enhancing functional recovery after stroke. A systematic literature review to study the association of stroke recovery with exosome therapy was carried out, analyzing species, stroke model, source of exosomes, behavioral analyses, and outcome data, as well as molecular mechanisms. Thirteen studies were included in the present systematic review. In the majority of studies, exosomes derived from mesenchymal stromal cells or stem cells were administered intravenously within 24 h after transient middle cerebral artery occlusion, showing a significant improvement of neurological severity and motor functions. Specific microRNAs and molecules were identified by mechanistic investigations, and their amplification was shown to further enhance therapeutic effects, including neurogenesis, angiogenesis, axonal outgrowth, and synaptogenesis. Overall, this review addresses the current advances in exosome therapy for stroke recovery in preclinical studies, which can hopefully be preparatory steps for the future development of clinical trials involving stroke survivors to improve functional outcomes.

Analysis of Clinical Symptoms and Brain MRI of Heat Stroke: 2 Case Reports and a Literature Review.

INTRODUCTION: Heat stroke is defined as high body temperature causing multiple organ failure, psychological change, seizure, and consciousness disturbance, which lead to its high mortality rate. However, the involvement of brain injury is rare, and heat-stroke has only been reported in a few case reports or case series. The purpose of this case study was to evaluate the clinical symptoms and radiological features of heat stroke. METHODS: We reviewed our hospital records and previously published reports to find cases of heat stroke. We excluded those with unknown clinical features or radiological findings. RESULTS: We retrieved 2 cases of heat stroke from our hospital, which presented as extensive lesions on brain imaging that led to disseminated intravascular coagulation and death within a few days. In 21 previously reported cases of heat stroke, similar brain lesions were noted. These were classified as infarction/posterior reversible encephalopathy syndrome (PRES)-like lesions. The patients who developed PRES-like lesions and survived often developed cerebellar sequelae. CONCLUSION: The mechanism of heat stroke is presumed to be multifactorial. Ischemic-like lesions result from hypovolemia and unusual coagulation, whereas PRES-like lesions are caused by direct heat and vasogenic edema due to hypercytokinemia. We need to consider the above mentioned conditions when evaluating heat stroke.

Cerebral Microbleeds and Chronic Kidney Disease in Acute Ischemic Stroke Patients with Atrial Fibrillation.

BACKGROUND: Cerebral microbleeds (CMBs) are associated with the risk of intracerebral hemorrhage in stroke patients with atrial fibrillation (AF). We investigated the association between CMBs and chronic kidney disease (CKD) in patients with acute ischemic stroke and AF. METHODS: We retrospectively examined consecutive patients with acute ischemic stroke and AF who underwent brain gradient-echo T2*-weighted magnetic resonance imaging. The number and distribution (lobar, deep or infratentorial, and mixed) of CMBs were assessed. Kidney function was assessed according to the estimated glomerular filtration rate (eGFR), which was calculated using a modified version of the Modification of Diet in Renal Disease equation. RESULTS: Of the 357 included patients, 105 (29.4%) had CMBs. CKD (eGFR < 60 mL/min/1.73 m2) was found in 131 (36.7%) patients. Patients with CKD showed a higher prevalence of any form of CMB (41.2% versus 22.6%, P < .001), deep or infratentorial CMBs (19.9% versus 9.3%, P < .01), and mixed CMBs (14.5% versus 5.3%, P < .01) than those without CKD. After adjusting for age and other confounding factors, CKD was found to be independently associated with the presence of any form of CMB (odds ratio 1.89, P = .02) and mixed CMBs (odds ratio 3.10, P < .01). Moreover, moderate to severe CKD (eGFR < 45 mL/min/1.73 m2) was independently associated with the presence of multiple CMBs (odds ratio 2.31, P = .04). CONCLUSIONS: CMBs and CKD are common in acute ischemic stroke patients with AF, and CKD may be a risk factor for CMBs. Further longitudinal studies are needed to evaluate whether maintaining kidney function can prevent the development of CMBs.

AKAP12 Supports Blood-Brain Barrier Integrity against Ischemic Stroke.

A-kinase anchor protein 12 (AKAP12) is a scaffolding protein that associates with intracellular molecules to regulate multiple signal transductions. Although the roles of AKAP12 in the central nervous system are still relatively understudied, it was previously shown that AKAP12 regulates blood-retinal barrier formation. In this study, we asked whether AKAP12 also supports the function and integrity of the blood-brain barrier (BBB). In a mouse model of focal ischemia, the expression level of AKAP12 in cerebral endothelial cells was upregulated during the acute phase of stroke. Also, in cultured cerebral endothelial cells, oxygen-glucose deprivation induced the upregulation of AKAP12. When AKAP12 expression was suppressed by an siRNA approach in cultured endothelial cells, endothelial permeability was increased along with the dysregulation of ZO-1/Claudin 5 expression. In addition, the loss of AKAP12 expression caused an upregulation/activation of the Rho kinase pathway, and treatment of Rho kinase inhibitor Y-27632 mitigated the increase of endothelial permeability in AKAP12-deficient endothelial cell cultures. These in vitro findings were confirmed by our in vivo experiments using Akap12 knockout mice. Compared to wild-type mice, Akap12 knockout mice showed a larger extent of BBB damage after stroke. However, the inhibition of rho kinase by Y-27632 tightened the BBB in Akap12 knockout mice. These data may suggest that endogenous AKAP12 works to alleviate the damage and dysfunction of the BBB caused by ischemic stress. Therefore, the AKAP12-rho-kinase signaling pathway represents a novel therapeutic target for stroke.

A-Kinase Anchor Protein 12 Is Required for Oligodendrocyte Differentiation in Adult White Matter.

Oligodendrocyte precursor cells (OPCs) give rise to oligodendrocytes in cerebral white matter. However, the underlying mechanisms that regulate this process remain to be fully defined, especially in adult brains. Recently, it has been suggested that signaling via A-kinase anchor protein 12 (AKAP12), a scaffolding protein that associates with intracellular molecules such as protein kinase A, may be involved in Schwann cell homeostasis and peripheral myelination. Here, we asked whether AKAP12 also regulates the mechanisms of myelination in the CNS. AKAP12 knockout mice were compared against wild-type (WT) mice in a series of neurochemical and behavioral assays. Compared with WTs, 2-months old AKAP12 knockout mice exhibited loss of myelin in white matter of the corpus callosum, along with perturbations in working memory as measured by a standard Y-maze test. Unexpectedly, very few OPCs expressed AKAP12 in the corpus callosum region. Instead, pericytes appeared to be one of the major AKAP12-expressing cells. In a cell culture model system, conditioned culture media from normal pericytes promoted in-vitro OPC maturation. However, conditioned media from AKAP12-deficient pericytes did not support the OPC function. These findings suggest that AKAP12 signaling in pericytes may be required for OPC-to-oligodendrocyte renewal to maintain the white matter homeostasis in adult brain. Stem Cells 2018;36:751-760.

Omega-3 Polyunsaturated Fatty Acids and Stroke Burden.

Stroke is a major leading cause of death and disability worldwide. N-3 polyunsaturated fatty acids (PUFAs) including eicosapentaenoic acid and docosahexaenoic acid have potent anti-inflammatory effects, reduce platelet aggregation, and regress atherosclerotic plaques. Since the discovery that the Greenland Eskimo population, whose diet is high in marine n-3 PUFAs, have a lower incidence of coronary heart disease than Western populations, numerous epidemiological studies to explore the associations of dietary intakes of fish and n-3 PUFAs with cardiovascular diseases, and large-scale clinical trials to identify the benefits of treatment with n-3 PUFAs have been conducted. In most of these studies the incidence and mortality of stroke were also evaluated mainly as secondary endpoints. Thus, a systematic literature review regarding the association of dietary intake of n-3 PUFAs with stroke in the epidemiological studies and the treatment effects of n-3 PUFAs in the clinical trials was conducted. Moreover, recent experimental studies were also reviewed to explore the molecular mechanisms of the neuroprotective effects of n-3 PUFAs after stroke.

Temporal Profile of CT and T2*-Weighted Gradient-Echo MRI in a Patient with Unilateral Thalamostriate Vein Thrombosis.

Deep cerebral venous system thrombosis (DCVST) is an uncommon variety of thrombosis that accounts for 11% of cases of cerebral venous thrombosis. Thalamostriate vein (TSV) thrombosis is further rare among patients with DCVST. Although patients with cerebral venous thrombosis commonly have characteristic neurological deficits including headache, deterioration of consciousness, and seizures, patients with DCVST do not necessarily show such symptoms. Therefore, diagnose of DCVST is sometimes difficult. Here we report a case of TSV thrombosis with a unilateral basal ganglion lesion presenting with right-sided hemiparesis. A 61-year-old Japanese female was referred to our hospital. On neurological examination, she had no headache but presented with right facial paresis with dysarthria. Her right hemiparesis was present in the upper and lower extremities. We repeatedly performed brain computed tomography (CT) and T2*-weighted conventional gradient-echo (GRE) magnetic resonance imaging, and conclusively diagnosed as left TSV thrombosis. We firstly report a case of unilateral DCVST associated with TSV thrombosis in which a temporal profile of CT and T2*-weighted GRE images was obtained. Although DCVST is a rare clinical entity, physicians should be aware that repeated radiological observations can be useful for the diagnosis and early medical treatment for DCVST.

Adequate Adherence to Direct Oral Anticoagulant is Associated with Reduced Ischemic Stroke Severity in Patients with Atrial Fibrillation.

BACKGROUND: The impact of adherence to direct oral anticoagulants (DOACs) is unknown. We aimed to assess the effects of preceding anticoagulation treatment on neurologic severity at admission and functional outcomes at discharge in patients with atrial fibrillation (AF) who developed acute ischemic stroke. METHODS: We retrospectively assessed consecutive patients with acute ischemic stroke and AF. Adherence to DOACs was assessed using the 4-item Morisky Medication Adherence Scale. Associations between preceding DOAC treatment and stroke severity at admission and functional outcomes at hospital discharge were examined. RESULTS: Of 387 patients with AF and acute ischemic stroke, 248 (64.1%) were not administered an anticoagulant before stroke onset, 95 (24.5%) had subtherapeutic warfarin with an international normalized ratio less than 2 at the time of stroke, 16 (4.1%) had therapeutic warfarin, 6 (1.6%) had DOACs with nonadherence, and 22 (5.7%) had DOACs with adequate adherence. Multivariate analysis showed that DOAC treatment with adequate adherence was associated with lower odds of severe stroke (National Institute of Health Stroke Scale ≥10 at admission) (odds ratio, .24; 95% confidence interval, .03-.98; P = .04) and higher odds of excellent recovery (modified Rankin Scale score, 0-1 at discharge) (odds ratio, 4.89; 95% confidence interval, 1.51-20.6; P < .01) compared with no anticoagulation therapy. CONCLUSIONS: Preceding DOAC treatment with adequate adherence has beneficial effects on stroke severity at admission and functional outcome at discharge in patients with AF. Hence, our results encourage an increased effort to bolster adherence to DOACs in patients with AF.

Astrocyte-Derived Exosomes Treated With a Semaphorin 3A Inhibitor Enhance Stroke Recovery via Prostaglandin D2 Synthase.

Background and Purpose- Exosomes play a pivotal role in neurogenesis. In the peri-infarct area after stroke, axons begin to regenerate but are inhibited by astrocyte scar formation. The direct effect and underlying molecular mechanisms of astrocyte-derived exosomes on axonal outgrowth after ischemia are not known. Methods- Using a semaphorin 3A (Sema3A) inhibitor, we explored neuronal signaling during axonal outgrowth after ischemia in rats subjected to middle cerebral artery occlusion and in cultured cortical neurons challenged with oxygen-glucose deprivation. Furthermore, we assessed whether this inhibitor suppressed astrocyte activation and regulated astrocyte-derived exosomes to enhance axonal outgrowth after ischemia. Results- In rats subjected to middle cerebral artery occlusion, we administered a Sema3A inhibitor into the peri-infarct area from 7 to 21 days after occlusion. We found that phosphorylated high-molecular weight neurofilament-immunoreactive axons were increased, glial fibrillary acidic protein-immunoreactive astrocytes were decreased, and functional recovery was promoted at 28 days after middle cerebral artery occlusion. In cultured neurons, the Sema3A inhibitor decreased Rho family GTPase 1, increased R-Ras, which phosphorylates Akt and glycogen synthase kinase 3ß (GSK-3ß), selectively increased phosphorylated GSK-3ß in axons, and thereby enhanced phosphorylated high-molecular weight neurofilament-immunoreactive axons after oxygen-glucose deprivation. In cultured astrocytes, the Sema3A inhibitor suppressed activation of astrocytes induced by oxygen-glucose deprivation. Exosomes secreted from ischemic astrocytes treated with the Sema3A inhibitor further promoted axonal elongation and increased prostaglandin D2 synthase expression on microarray analysis. GSK-3ß+ and prostaglandin D2 synthase+ neurons were robustly increased after treatment with the Sema3A inhibitor in the peri-infarct area. Conclusions- Neuronal Rho family GTPase 1/R-Ras/Akt/GSK-3ß signaling, axonal GSK-3ß expression, and astrocyte-derived exosomes with prostaglandin D2 synthase expression contribute to axonal outgrowth and functional recovery after stroke.

Bilateral Caudate Nucleus Infarctions Following Upper Gastrointestinal Bleeding.

A 75-year-old woman presented with consciousness disturbance accompanied by hematemesis. Brain imaging revealed ischemia in the bilateral caudate nuclei and right cerebral watershed area due to stenosis of the right anterior cerebral artery (ACA) and bilateral internal carotid arteries (ICA), and hypoperfusion in the right caudate nucleus. The patient's only symptom was abulia, which gradually resolved. Further brain scans showed that the ICA stenosis had improved, although the right ACA stenosis persisted. This was a rare case of bilateral caudate nucleus infarctions with a hemodynamic etiology.

The Importance of Combined Antithrombotic Treatment for Capsular Warning Syndrome.

INTRODUCTION: Capsular warning syndrome (CWS) is characterized by recurrent conventional episodes of motor and/or sensory deficits without cortical symptoms. The purpose of this case series study was to evaluate the safety and appropriate treatment for CWS to prevent the development of complete stroke. METHODS: We reviewed our hospital records and previous reports to find patients with neurologically fluctuating profiles, and excluded those with unknown details of initial treatment/final treatment of antiplatelet therapy or radiological findings. RESULTS: We retrieved two cases of CWS from our hospital, which presented motor and/or sensory symptoms followed by complete resolution without complete ischemia. The recurring episodes in both were unable to be stabilized by single antiplatelet therapy but were successfully managed using two or more antiplatelet drugs. In 11 previously reported cases of CWS, the recurring episode was frequency stabilized with plural antiplatelet therapy. CONCLUSION: Multiplicate antiplatelet therapy is important for treatment of CWS, and caution is needed regarding hemorrhagic complications.

Conjugate Eye Deviation Caused by Upper Medial Medullary Infarction: A Case Report.

Conjugate eye deviation (CED) is defined as a sustained shift in horizontal gaze toward 1 side, together with gaze failure to the other side, caused by lesions in the brainstem, basal ganglia, or cortical frontal eye fields. To date, very few reports have described CED in patients with medullary infarction. A 76-year-old woman presented with sudden onset of vertigo and right hemiparesis, accompanied by CED to the right with gaze palsy to the left. Her brain magnetic resonance imaging showed left upper medial medullary infarction involving the left nucleus prepositus hypoglossi (NPH) and adjacent to the left inferior olivary nucleus (ION). After treatments with 200 mg of aspirin and 60 mg of edaravone daily, symptoms gradually improved. The NPH and ION constitute NPH-ION-floccus-vestibular nucleus loop and contribute to the inhibitory mechanisms for horizontal eye movements. In addition, NPH projects excitatory neurons to the contralateral vestibular nucleus. In our case, disorders of the NPH and ION might have dysregulated inhibitory and excitatory projections, and thereby cause CED to the right with gaze palsy to the left. This represents a rare case showing CED to the contralesional side in upper medial medullary infarction.