Qingfeng Ma

The rs10947803 SNP of KCNK17 is associated with cerebral hemorrhage but not ischemic stroke in a Chinese population

KCNK17 (potassium channel, subfamily K, member17) was first discovered to associate with the pathogenesis of ischemic stroke in the first genome-wide association study. The rs10947803 SNP in KCNK17 is significantly associated with ischemic stroke in Caucasian populations. The aim of the present study was to investigate the association with strokes in the Chinese population. A total of 1364 stroke patients and 1293 controls were examined using a case-control methodology. The rs10947803 SNP in KCNK17 was genotyped by a TaqMan real-time PCR assay. The rs10947803 SNP (A allele) of KCNK17 was significantly associated with cerebral hemorrhage (for AA+AC versus CC, unadjusted odds ratio [OR]=1.70; 95% confidence interval [CI], 1.08-2.69; P=0.020). After adjustment for age and sex, the association remained significant for AA+AC versus CC, OR=1.65; 95% CI, 1.04-2.62; P=0.033. In addition, the rs10947803 SNP in KCNK17 was not associated with ischemic stroke (for AA+AC versus CC, unadjusted OR=0.92; 95% CI, 0.81-1.05; P=0.212, after age- and sex-adjustment, OR=0.87; 95% CI, 0.72-1.05; P=0.143). The rs10947803 SNP (A allele) in KCNK17 increases the risk of cerebral hemorrhage but not ischemic stroke in the Chinese population.

Normobaric Hyperoxia Reduces Blood Occludin Fragments in Rats and Patients With Acute Ischemic Stroke

Background and Purpose— Damage of the blood–brain barrier (BBB) increases the incidence of neurovascular complications, especially for cerebral hemorrhage after tPA (tissue-type plasminogen activator) therapy. Currently, there is no effective method to evaluate the extent of BBB damage to guide tPA use. Herein, we investigated whether blood levels of tight junction proteins could serve as biomarker of BBB damages in acute ischemic stroke (AIS) in both rats and patients. We examined whether this biomarker could reflect the extent of BBB permeability during cerebral ischemia/reperfusion and the effects of normobaric hyperoxia (NBO) on BBB damage. Methods— Rats were exposed to NBO (100% O2) or normoxia (21% O2) during middle cerebral artery occlusion. BBB permeability was determined. Occludin and claudin-5 in blood and cerebromicrovessels were measured. Patients with AIS were assigned to oxygen therapy or room air for 4 hours, and blood occludin and claudin-5 were measured at different time points after stroke. Results— Cerebral ischemia/reperfusion resulted in the degradation of occludin and claudin-5 in microvessels, leading to increased BBB permeability in rats. In blood samples, occludin increased with 4-hour ischemia and remained elevated during reperfusion, correlating well with its loss from ischemic cerebral microvessels. NBO treatment both prevented occludin degradation in microvessels and reduced occludin levels in blood, leading to improved neurological functions in rats. In patients with AIS receiving intravenous tPA thrombolysis, the blood occludin was already elevated when patients arrived at hospital (within 4.5 hours since symptoms appeared) and remained at a high level for 72 hours. NBO significantly lowered the level of blood occludin and improved neurological functions in patients with AIS. Conclusions— Blood occludin may be a clinically viable biomarker for evaluating BBB damage during ischemia/reperfusion. NBO therapy has the potential to reduce blood occludin, protect BBB, and improve outcome in AIS patients with intravenous tPA thrombolysis. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT02974283.

Association of Variants in KCNK17 Gene with Ischemic Stroke and Cerebral Hemorrhage in a Chinese Population

BACKGROUNDnKCNK17 (potassium channel, subfamily K, member17) has a role in the pathogenesis of stroke. We reported previously that rs10947803 single-nucleotide polymorphism (SNP) in KCNK17 is associated with cerebral hemorrhage in a Chinese population. The aim of the present study was to examine other SNPs in the KCNK17 gene that are associated with cerebral hemorrhage and other subtypes of stroke in the Chinese population.nnnMETHODSnA total of 1356 subjects with stroke and 1225 control patients were examined by a case-control methodology. The SNPs (rs12214600, rs12195376, rs2758912, and rs10807204) in KCNK17 gene were genotyped with the TaqMan real-time polymerase chain reaction assay.nnnRESULTSnrs12214600 SNP in KCNK17 was significantly associated with cerebral hemorrhage (unadjusted odds ratio = .55, 95% confidence interval = .35-.86, P = .008, q = .0328) under the allele model. After adjusting for age, sex, and hypertension, we found that the association remained significant (odds ratio = .56, 95% confidence interval = .35-.90, P = .0158). There was no association detected for other SNPs in KCNK17 with cerebral hemorrhage, and none of the SNPs in KCNK17 had an association with ischemic stroke.nnnCONCLUSIONSnThe T carrier of an SNP (rs12214600) is associated with reduced risk of cerebral hemorrhage in the Chinese population, together with previous findings that SNPs rs10947803 and rs12214600 in the KCNK17 gene are associated with hemorrhagic stroke, but none of the SNPs tested had an association with ischemic stroke. KCNK17 may be important in the pathogenesis of cerebral hemorrhage.

Elevated trimethylamine N-oxide related to ischemic brain lesions after carotid artery stenting

Objectives To investigate whether the plasma level of trimethylamine N-oxide (TMAO), a proatherosclerotic intestinal microbiota metabolite, can be a predictor of ischemic brain injury secondary to carotid artery stenting (CAS). Methods In this multicenter, prospective cohort study, we enrolled patients with severe carotid artery stenosis (>70%) who were prepared for CAS. Plasma TMAO level was measured within 3 days before CAS, and MRI was performed 1 to 3 days after CAS. Results The mean age of the 268 eligible patients was 64.4 years. New lesions on diffusion-weighted imaging (DWI) were detected in 117 patients (43.7%). TMAO level was higher in patients with new (DWI) lesions than in patients without new lesions (median 5.2 vs 3.2 µmol/L; p < 0.001). Increased plasma TMAO levels were associated with an increased risk of having new lesions on DWI after CAS (adjusted odds ratio for the highest vs lowest quartile, 3.85; 95% confidence interval, 1.37–7.56, p < 0.001; adjusted odds ratio for the third vs lowest quartile, 1.86; 95% confidence interval, 1.09–4.66, p = 0.02). The area under the receiver operating characteristic curve of TMAO was 0.706 for new lesions on DWI, and the optimal cutoff value was 4.29 µmol/L. The sensitivity, specificity, positive predictive value, and negative predictive value of TMAO levels ≥4.29 µmol/L for predicting new lesions on DWI were 61.5%, 74.8%, 65.5%, and 65.5%, respectively. Conclusions Increased TMAO levels are associated with an increased risk of new ischemic brain lesions on post-CAS MRI scans.

Abstract 54: Combined Vessel Wall and Perforator Imaging for Prediction of Stroke Subtype

Objective: The aim of the present study was to evaluate atherosclerotic plaque characteristics and perforating arteries together by high-resolution magnetic resonance imaging (HRMRI) and to establi...

Outcome of endovascular treatment for acute basilar artery occlusion in the modern era: a single institution experience

PurposeThe beneficial effect of endovascular treatment (EVT) for patients with acute basilar artery occlusion (ABAO) remains uncertain. The purpose of the present study was to evaluate clinical outcome of EVT for patients with ABAO and analyze prognostic factors of good outcome.MethodsFrom our prospectively established database, we reviewed all patients with ABAO receiving EVT during January 2014 to December 2016. Baseline characteristics and outcomes were evaluated. Favorable functional outcome was defined as modified Rankin Scale score of 0 to 3 assessed at 3-month follow-up. The association between clinical and procedural characteristics and functional outcome was assessed.ResultsOf the 68 patients included, 50 patients (73.5%) received mechanical thrombectomy with stent retriever device. Successful reperfusion (thrombolysis in cerebral infarction grades 2b–3) was achieved in 61 patients (89.7%). Overall favorable functional outcome was reached by 31 patients (45.6%). In univariate analysis, Glasgow Coma Scale sum score, baseline National Institutes of Health stroke scale score (NIHSS), and baseline glycemia level were identified predicting good clinical outcome. Multivariate analysis showed that lower NIHSS was the only independent risk factor of favorable functional outcome (OR 0.832; 95% CI, 0.715–0.968; pu2009=u20090.018). No difference of favorable outcomes was observed between the subgroups of time to EVTu2009<u20096xa0h and ≽xa06xa0h.ConclusionsData in the present study suggests that EVT for ABAO patients should be reasonable within 24xa0h of symptom onset. The most important factor determining clinical outcome is initial stroke severity.

Low Serum Albumin level as a Predictor of Hemorrhage Transformation after Intravenous Thrombolysis in Ischemic Stroke Patients

Serum albumin levels has been shown to predict outcome in ischemic stroke patients. We aimed to investigate the relationship between serum albumin levels and hemorrhagic transformation (HT) after intravenous thrombolysis (IVT) in patients with acute stroke. 428 patients receiving intravenous rt-PA therapy were included from 2013 to 2016 and were categorized into two groups: low level (<35u2009mmol/L) and normal level (35–55u2009mmol/L) group. Demographic, clinical and laboratory information, HT and functional outcomes were analyzed. Hemorrhagic transformation was comfirmed by CT scan or MRI within 7 days. The functional outcome was measured by modified Barthel Index and modified Rankin Scale (mRS) at 7 days and 90 days. Patients with lower albumin had significantly higher risk of HT (15.3% vs. 4.2%, Pu2009=u20090.002) and sICH (6.2% vs. 1.4%, Pu2009=u20090.03) than those with normal level of albumin. In univariate analysis for HT, atrial fibrillation and level of albumin were identified as significant factors (Pu2009<u20090.001, Pu2009=u20090.001 respectively). On multivariate logistic regression analysis, serum albumin level remained independent predictor of HT (ORu2009=u20094.369, 95% CIu2009=u20091.626–11.742, Pu2009=u20090.003). No significantly difference were found in the clinical outcome at 7 days and 90 days between two groups ufeff(Pu2009>u20090.05). Low level of serum albumin within 24u2009hours may be an independent predictor of post-thrombolytic HT.

Relationship between Post-Thrombolysis Blood Pressure and Outcome in Acute Ischemic Stroke Patients Undergoing Thrombolysis Therapy

BACKGROUNDnThe management of blood pressure (BP) for acute ischemic stroke (AIS) patients undergoing thrombolysis is still under debate. The purpose of this study was (1) to explore the association between post-thrombolysis BP and functional outcome and (2) to examine whether post-thrombolysis BP can predict functional outcome in Chinese AIS patients undergoing thrombolysis therapy.nnnMETHODSnFrom December 2012 to November 2016, AIS patients undergoing thrombolysis were reviewed retrospectively in the Department of Neurology at Xuanwu Hospital. The BP levels were measured before and immediately after thrombolysis. Clinical outcomes, which comprised favorable outcome (modified Rankin Scale score 0-2) and unfavorable outcome (modified Rankin Scale score 3-6) at 3 months, were analyzed by logistic regression model. A receiver operating characteristic curve was used to evaluate the predictive value of post-thrombolysis BP.nnnRESULTSnPatients with unfavorable outcome at 3 months had a higher post-thrombolysis systolic BP than those with favorable outcome (Pu2009=u2009.015). Multivariate analysis showed that post-thrombolysis systolic BP below 159.5u2009mmu2009Hg was associated with favorable outcome. According to the receiver operating characteristic curve, post-thrombolysis systolic BP was a predictor of functional outcome with an area under the curve of .573 (95% confidence intervalu2009=u2009.504-.642).nnnCONCLUSIONSnOur study indicated that post-thrombolysis systolic BP is a predictor of functional outcome for Chinese AIS patients undergoing thrombolysis therapy. It is reasonable for AIS patients to keep post-thrombolysis systolic BP below 159.5u2009mmu2009Hg to obtain a favorable outcome.