Free water in gray matter linked to gut microbiota changes with decreased butyrate producers in Alzheimer's disease and mild cognitive impairment.

Neuroinflammation contributes to the pathology and progression of Alzheimer's disease (AD), and it can be observed even with mild cognitive impairment (MCI), a prodromal phase of AD. Free water (FW) imaging estimates the extracellular water content and has been used to study neuroinflammation across several neurological diseases including AD. Recently, the role of gut microbiota has been implicated in the pathogenesis of AD. The relationship between FW imaging and gut microbiota was examined in patients with AD and MCI. Fifty-six participants underwent neuropsychological assessments, FW imaging, and gut microbiota analysis targeting the bacterial 16S rRNA gene. They were categorized into the cognitively normal control (NC) (n = 19), MCI (n = 19), and AD (n = 18) groups according to the neuropsychological assessments. The correlations of FW values, neuropsychological assessment scores, and the relative abundance of gut microbiota were analyzed. FW was higher in several white matter tracts and in gray matter regions, predominantly the frontal, temporal, limbic and paralimbic regions in the AD/MCI group than in the NC group. In the AD/MCI group, higher FW values in the temporal (superior temporal and temporal pole), limbic and paralimbic (insula, hippocampus and amygdala) regions were the most associated with worse neuropsychological assessment scores. In the AD/MCI group, FW values in these regions were negatively correlated with the relative abundances of butyrate-producing genera Anaerostipes, Lachnospiraceae UCG-004, and [Ruminococcus] gnavus group, which showed a significant decreasing trend in the order of the NC, MCI, and AD groups. The present study showed that increased FW in the gray matter regions related to cognitive impairment was associated with low abundances of butyrate producers in the AD/MCI group. These findings suggest an association between neuroinflammation and decreased levels of the short-chain fatty acid butyrate that is one of the major gut microbial metabolites having a potentially beneficial role in brain homeostasis.

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.

Comparison of primary and secondary stroke prevention in patients with nonvalvular atrial fibrillation: Results from the RAFFINE registry.

OBJECTIVES: Clinical outcome data of primary and secondary prevention in patients with nonvalvular atrial fibrillation (NVAF) after the introduction of direct oral anticoagulant (DOAC) therapy are limited. MATERIALS AND METHODS: A subgroup analysis of the RAFFINE registry, an observational, multicenter, prospective registry of Japanese patients with AF, was performed. Incidence rates of stroke or systemic embolism, all-cause death, major bleeding, and intracranial hemorrhage were compared between patients with and without a history of stroke or transient ischemic attack (TIA). RESULTS: Of 3,706 NVAF patients at baseline, 557 (15.0%) had a history of ischemic stroke or TIA (secondary prevention group), and 3,149 (85.0%) had no history of ischemic stroke or TIA (primary prevention group). The proportion of patients receiving oral anticoagulants was 87.2% (42.5% warfarin, 44.7% DOACs). The secondary prevention group had higher rates of stroke or systemic embolism (2.6% vs 1.0%/year, p<0.001), all-cause death (3.6% vs 2.4%/year, p<0.01), and major bleeding (2.0% vs 1.3%/year, p<0.01), and similar rates of intracranial hemorrhage (0.6% vs 0.5%/year, p=0.66) compared with the primary prevention group. A Cox proportional hazards model showed that a history of ischemic stroke or TIA was independently associated with an increased risk of stroke or systemic embolism (adjusted hazard ratio, 2.22; 95% confidence interval, 1.57 - 3.15; p<0.001). CONCLUSIONS: In a contemporary cohort of NVAF patients, a history of ischemic stroke or TIA was still an independent predictor of stroke or systemic embolism, despite advances in anticoagulation therapy.

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.

Role of the Gut Microbiota in Stroke Pathogenesis and Potential Therapeutic Implications.

BACKGROUND: Major advances have been made in stroke treatment and prevention in the past decades. However, the burden of stroke remains high. Identification of novel targets and establishment of effective interventions to improve stroke outcomes are, therefore, needed. Recent research highlights the contribution of the gut microbiota to stroke pathogenesis. SUMMARY: Compositional and functional alterations of the gut microbiota, termed dysbiosis, are linked to stroke risk factors, such as obesity, metabolic diseases, and atherosclerosis. In acute cerebral ischemia, the gut microbiota plays a key role in bidirectional interactions between the gut and brain, referred to as the microbiota-gut-brain axis. Gut dysbiosis prior to ischemic stroke affects outcomes. Additionally, the brain affects the gut microbiota during acute ischemic brain injury, which in turn impacts outcomes. Interactions between the gut microbiota and stroke pathogenesis are mediated by several factors including bacterial components (e.g., lipopolysaccharide), gut microbiota-related metabolites (e.g., short-chain fatty acids and trimethylamine N-oxide), and the immune and nervous systems. Clinical studies have reported that patients with acute ischemic stroke exhibit gut dysbiosis, which is associated with host metabolism and inflammation, as well as functional outcomes. Modulation of the gut microbiota or its metabolites improves conditions related to stroke pathogenesis, including inflammation, cardiometabolic disease, atherosclerosis, and thrombosis. Key Messages: Accumulating evidence indicates that the gut microbiota plays a possible role in stroke pathogenesis. Modulation of the gut microbiota may provide a novel therapeutic strategy for the treatment and prevention of stroke.

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.

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.

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.

Glycyl-alanyl-histidine protects PC12 cells against hydrogen peroxide toxicity.

BACKGROUND: Peptides with cytoprotective functions, including antioxidants and anti-infectives, could be useful therapeutics. Carnosine, ß-alanine-histidine, is a dipeptide with anti-oxidant properties. Tripeptides of Ala-His-Lys, Pro-His-His, or Tyr-His-Tyr are also of interest in this respect. RESULTS: We synthesized several histidine-containing peptides including glycine or alanine, and tested their cytoprotective effects on hydrogen peroxide toxicity for PC12 cells. Of all these peptides (Gly-His-His, Ala-His-His, Ala-His-Ala, Ala-Ala-His, Ala-Gly-His, Gly-Ala-His (GAH), Ala-His-Gly, His-Ala-Gly, His-His-His, Gly-His-Ala, and Gly-Gly-His), GAH was found to have the strongest cytoprotective activity. GAH decreased lactate dehydrogenase (LDH) leakage, apoptosis, morphological changes, and nuclear membrane permeability changes against hydrogen peroxide toxicity in PC12 cells. The cytoprotective activity of GAH was superior to that of carnosine against hydrogen peroxide toxicity in PC12 cells. GAH also protected PC12 cells against damage caused by actinomycin D and staurosporine. Additionally, it was found that GAH also protected SH-SY5Y and Jurkat cells from damage caused by hydrogen peroxide, as assessed by LDH leakage. CONCLUSION: Thus, a novel tripeptide, GAH, has been identified as having broad cytoprotective effects against hydrogen peroxide-induced cell damage.

Acute Hearing Loss Caused by Decreasing Anterior Inferior Cerebellar Arterial Perfusion in a Patient with Vertebral Artery Stenosis.

We report a case of bilateral hearing loss caused by decreased vascular flow in the anterior inferior cerebellar artery (AICA) territory. A 74-year-old man who experienced right hearing loss 5 months ago presented with bilateral deafness and right cerebellar ataxia; however, no ischemic lesion was detected in the bilateral AICA area. After stroke treatment, hearing loss was improved. One month later, we obtained blood flow improvement in the left AICA territory on single-photon-emission computed tomography and vertebral artery stenosis on magnetic resonance angiography. Therefore, clinicians should recognize that bilateral hearing loss may be related to stroke in the vertebrobasilar artery area.

Analysis of the Usefulness of the WORSEN Score for Predicting the Deterioration of Acute Ischemic Stroke.

BACKGROUND: Early neurological worsening is associated with increased mortality and long-term functional disability. We developed the WORSEN score for predicting whether patients with stroke will deteriorate during the week after stroke onset and investigated its usefulness. PATIENTS AND METHODS: We retrospectively investigated the cases of 478 patients who were admitted to Juntendo University Hospital between April 2007 and March 2009. Neurological deterioration was defined as a worsening of 4 points or higher on the National Institute of Health Stroke Scale score within 1 week of admission. Based on a previous study, we developed the WORSEN score, which was derived from the following factors: wrong (poor) blood sugar control (W), old myocardial infarction (O), radiological findings (R), infarct size (S), elevated low-density lipoprotein cholesterol (E), and neurological findings (N). Next, we investigated the utility of this scoring system in 456 other patients who were admitted to Juntendo University Hospital and Juntendo Urayasu Hospital between October 2013 and December 2014. RESULTS: First, we checked the utility of the WORSEN score for detecting worsening in cases of stroke. In the first patient group, deterioration was noted in 32.5% of the patients with scores higher than 3 points (sensitivity: .704 and specificity: .744). For checking reproductivity on using the second group, deterioration was detected in 36.1% of the patients with WORSEN scores higher than 3 points (sensitivity: .740 and specificity: .835). CONCLUSIONS: Careful attention should be paid to patients with acute stroke with high WORSEN scores. The WORSEN score might become a valuable tool for detecting the neurological deterioration of ischemic stroke.

Limb-Shaking Transient Ischemic Attack Induced by Middle Cerebral Artery Dissection after Lung Surgery.

We report a case of limb-shaking transient ischemic attack (TIA) caused by a dissection of the middle cerebral artery (MCA) following lung surgery under general anesthesia. An 81-year-old male patient who underwent lobectomy for lung cancer suddenly developed transient shaking movements of the neck and the left upper distal limb on postoperative day 1. On the basis of the double-barrel appearance of the right M1 segment of the MCA, a diagnosis of MCA dissection was made. Physicians should be aware that limb-shaking TIA is sometimes caused by MCA dissection and could be precipitated by any condition, including lung surgery under general anesthesia.

Exendin-4 Inhibits Matrix Metalloproteinase-9 Activation and Reduces Infarct Growth After Focal Cerebral Ischemia in Hyperglycemic Mice.

BACKGROUND AND PURPOSE: Admission hyperglycemia is an independent risk factor for poor outcome of ischemic stroke. Amelioration of hyperglycemia by insulin has not been shown to improve the poststroke outcome. Glucagon-like peptide 1 receptor agonists, which modulate glucose levels by stimulating insulin secretion, have been shown to exert cytoprotective effects by inhibiting inflammation and oxidative stress. This study aimed to evaluate whether the glucagon-like peptide 1 receptor agonist exendin-4 could reduce glucose levels and exert protective effects after acute focal ischemia in hyperglycemic mice. METHODS: Hyperglycemia was induced by intraperitoneal injection of dextrose 15 minutes before transient middle cerebral artery occlusion was performed for 60 minutes using an intraluminal thread. We assessed 4 groups: (1) normal glucose (vehicle control), (2) induced hyperglycemia, (3) induced hyperglycemia with insulin treatment, and (4) induced hyperglycemia with exendin-4 treatment. Neurovascular injuries in brains from each group were evaluated 24 hours and 7 days post ischemia. RESULTS: Hyperglycemia significantly increased infarct volume (36.3±1.20 versus 26.9±1.28; P<0.001), brain edema (P<0.05), and hemorrhagic transformation compared with control (P<0.001). This increase in infarct volume was associated with increased blood-brain barrier disruption and matrix metalloproteinase-9 activation. Exendin-4, but not insulin, attenuated matrix metalloproteinase-9 activation, proinflammatory cytokine (tumor necrosis factor-α) release, and biomarkers of oxidative stress and showed significant inhibition of infarct growth at 24 hours (23.6±0.97 versus 36.3±1.20; P<0.001) and at 7 days after ischemia (21.0±0.92 versus 29.3±1.41; P<0.001). CONCLUSIONS: Treatment with exendin-4 could be a potentially useful therapeutic option for treatment of acute ischemic stroke with transient hyperglycemia.