Ischemic Stroke in Patients With Intracranial Dural Arteriovenous Fistulas

Background/PurposeIntracranial dural arteriovenous fistulas (DAVFs) can be complicated by ischemic stroke. This study investigated the frequency and determinants of ischemic stroke in patients with intracranial DAVF.MethodsWe conducted a retrospective study of consecutive patients with intracranial DAVF. Patients with pure hemorrhagic stroke or without available brain imaging for clarifying stroke type were excluded. DAVF was diagnosed by cerebral catheter angiography. Cognard classification and location of DAVFs were ascertained. The clinical characteristics, outcome, and radiographic findings were recorded. Factors associated with occurrence of ischemic stroke in the patients with DAVFs were determined.ResultsA total of 134 patients were enrolled. Six patients (4.5%) had ischemic stroke (mean age: 53.8 ± 13.4 years) and 128 patients were free from stroke (mean age: 55.4 ± 15.2 years). Men accounted for 83% in the ischemic stroke group and 34% in the non-stroke group. Chemosis, exophthalmos and tinnitus were more frequent in the non-stroke group, whereas seizure and mental decline were more frequent in the ischemic stroke group. DAVF was associated with highest risk of ischemic stroke at locations other than the cavernous sinus or large sinuses. Ischemic stroke also correlated with types of DAVF involving cortical venous drainage, including type IIb (18%), III (15%), and IV (100%). No patient with DAVF type I and IIa had ischemic stroke. The rate of ischemic stroke in patients with concomitant DAVF and cerebral sinus thrombosis was higher than in DAVF patients without cerebral sinus thrombosis. Venous infarct was the major subtype of ischemic stroke in five DAVF patients. Endovascular therapy was the most common choice in both groups, and fewer patients in the ischemic stroke group did not receive any treatment for DAVFs.ConclusionLocation and type of DAVF were two important factors related to the occurrence of ischemic stroke in DAVF patients

Association between plasma levels of hyaluronic acid and functional outcome in acute stroke patients

BACKGROUND: Activation of hyaluronic acid (HA) and associated enzyme synthesis has been demonstrated in experimental stroke animal models. Our study aimed to investigate the plasma levels of HA in acute stroke patients and the associations between HA levels and functional outcome. METHODS: This was a multicenter case–control study. Acute stroke patients and age- and sex-matched non-stroke controls were recruited. Plasma levels of HA in acute stroke patients were determined at <48 hours and at 48 to 72 hours after stroke onset by standard ELISA. Favorable functional outcome was defined as modified Rankin scale ≤2 at 3 months after stroke. RESULTS: The study included 206 acute stroke patients, including 43 who had intracerebral hemorrhage and 163 who had ischemic stroke, and 159 controls. The plasma levels of HA in the acute stroke patients were significantly higher than those in the controls (219.7 ± 203.4 ng/ml for <48 hours and 343.1 ± 710.3 ng/ml for 48 to 72 hours versus 170.4 ± 127.9 ng/ml in the controls; both P < 0.05). For intracerebral hemorrhage patients, HA ≤500 ng/ml (<48 hours) was an independent favorable outcome predictor (P = 0.016). For ischemic stroke patients, an inverted U-shaped association between plasma HA (48 to 72 hours) and outcome was noted, indicating that ischemic stroke patients with too high or too low plasma HA levels tended to have an unfavorable outcome. CONCLUSION: HA plasma level was elevated in patients with acute stroke, and can predict 3-month functional outcome, particularly for patients with intracerebral hemorrhage

Localized tail state distribution and hopping transport in ultrathin zinc-tin-oxide thin film transistor

Carrier transport properties of solution processed ultra thin (4 nm) zinc-tin oxide (ZTO) thin film transistor are investigated based on its transfer characteristics measured at the temperature ranging from 310K to 77K. As temperature decreases, the transfer curves show a parellel shift toward more postive voltages. The conduction mechanism of ultra-thin ZTO film and its connection to the density of band tail states have been substantiated by two approaches, including fitting logarithm drain current (log ID) to T-1/3 at 310K to 77K according to the two-dimensional Mott variable range hopping theory and the extraction of density of localized tail states through the energy distribution of trapped carrier density. The linear dependency of log ID vs. T-1/3 indicates that the dominant carrier transport mechanism in ZTO is the variable range hopping. The extracted value of density of tail states at the conduction band minimum is 4.75 x 10(20) cm(-3) eV(-1) through the energy distribution of trapped carrier density. The high density of localized tail states in the ultra thin ZTO film is the key factor leading to the room-temperature hopping transport of carriers among localized tail states. Published by AIP Publishing

Association between genetic variant on chromosome 12p13 and stroke survival and recurrence: a one year prospective study in Taiwan

<p>Abstract</p> <p>Background</p> <p>The association between ischemic stroke and 2 single nucleotide polymorphisms (SNPs) on chromosome 12p13, rs12425791 and rs11833579 appears inconsistent across different samples. These SNPs are close to the ninjurin2 gene which may alter the risk of stroke by affecting brain response to ischemic injury. The purpose of this study was to investigate the association between these two SNPs and ischemic stroke risk, as well as prognostic outcomes in a Taiwanese sample.</p> <p>Methods</p> <p>We examined the relations of these two SNPs to the odds of new-onset ischemic stroke, ischemic stroke subtypes, and to the one year risk of stroke-related death or recurrent stroke following initial stroke in a case-control study. A total of 765 consecutive patients who had first-ever ischemic stroke were compared to 977 stroke-free, age-matched controls. SNPs were genotyped by Taqman fluorescent allelic discrimination assay. The association between ischemic stroke and SNPs were analyzed by multivariate logistic regression. Cox proportional hazard model was used to assess the effect of individual SNPs on stroke-related mortality or recurrent stroke.</p> <p>Results</p> <p>There was no significant association between SNP rs12425791 and rs11833579 and ischemic stroke after multiple testing corrections. However, the marginal significant association was observed between SNP rs12425791 and large artery atherosclerosis under recessive model (OR, 2.30; 95%CI, 1.22-4.34; q-value = 0.062). Among the 765 ischemic stroke patients, 59 died or developed a recurrent stroke. After adjustment for age, sex, vascular risk factors and baseline stroke severity, Cox proportional hazard analysis indicated that the hazard ratios were 2.76 (95%CI, 1.34-5.68; q-value, 0.02) and 2.15 (95%CI, 1.15-4.02; q-value, 0.03) for individuals with homozygous variant allele of rs12425791 and rs11833579, respectively.</p> <p>Conclusions</p> <p>This is a precedent study that found genetic variants of rs12425791 and rs11833579 on chromosome 12p13 are independent predictors of stroke-related mortality or stroke recurrence in patients with incident ischemic stroke in Taiwan. Further study is needed to explore the details of the physiological function and the molecular mechanisms underlying the association of this genetic locus with ischemic stroke.</p

Neuroanatomy- and Pathology-Based Functional Examinations of Experimental Stroke in Rats: Development and Validation of a New Behavioral Scoring System

In experimental stroke studies, a neuroanatomy-based functional examination of behaviors is critical to predict the pathological extent of infarcts because brain-imaging studies are not always available. However, there is a lack of systematic studies to examine the efficiency of a behavioral test for this purpose. Our work aimed to design a new score for this goal in stroke rats, by simplifying the Garcia score (with subscore 1–6) and adding circling as subscore 7. MRI and 2,3,5-triphenyltetrazolium chloride staining were used to determine the pathological extent after transient middle cerebral artery occlusion. The modified summations of subscores were designed according to the predictability of each subscore for locations and sizes of infarcts in one group of stroke rats, and were validated in another group. The original Garcia score was able to predict the pathological extent of edema-adjusted infarct size ≥30%, and the summation of subscore 4, 6, and 7 (4: climbing, 6: vibrissae sensation, 7: circling) also could predict it well. The original Garcia score failed to predict infarct at the primary motor cortex, while the summation of subscore 4, 6, and 7 potentially could predict not only the primary motor cortex, but also the forelimb, hindlimb, and barrel field regions of the primary sensory cortex. Accordingly, this neuroanatomy-correlated functional assessment system composed of subscore 4, 6, and 7 was proposed, with less examination time and better inter-rater reliability than the original Garcia score. In summary, this new scoring system, summation (4,6,7) score, examined motor and sensory functions based on neuroanatomical involvement, having the potential to predict the pathological extent and specific relevant brain areas of infarcts, respectively

Acute dual antiplatelet therapy for minor ischaemic stroke or transient ischaemic attack

International audienc

Tranexamic acid for intracerebral haemorrhage within 2 hours of onset : protocol of a phase II randomised placebo-controlled double-blind multicentre trial

Rationale Haematoma growth is common early after intracerebral haemorrhage (ICH), and is a key determinant of outcome. Tranexamic acid, a widely available antifibrinolytic agent with an excellent safety profile, may reduce haematoma growth. Methods and design Stopping intracerebral haemorrhage with tranexamic acid for hyperacute onset presentation including mobile stroke units (STOP-MSU) is a phase II double-blind, randomised, placebo-controlled, multicentre, international investigator-led clinical trial, conducted within the estimand statistical framework. Hypothesis In patients with spontaneous ICH, treatment with tranexamic acid within 2 hours of onset will reduce haematoma expansion compared with placebo. Sample size estimates A sample size of 180 patients (90 in each arm) would be required to detect an absolute difference in the primary outcome of 20% (placebo 39% vs treatment 19%) under a two-tailed significance level of 0.05. An adaptive sample size re-estimation based on the outcomes of 144 patients will allow a possible increase to a prespecified maximum of 326 patients. Intervention Participants will receive 1 g intravenous tranexamic acid over 10 min, followed by 1 g intravenous tranexamic acid over 8 hours; or matching placebo. Primary efficacy measure The primary efficacy measure is the proportion of patients with haematoma growth by 24 +/- 6 hours, defined as either >= 33% relative increase or >= 6 mL absolute increase in haematoma volume between baseline and follow-up CT scan. Discussion We describe the rationale and protocol of STOP-MSU, a phase II trial of tranexamic acid in patients with ICH within 2 hours from onset, based in participating mobile stroke units and emergency departments.Peer reviewe