Current neurovascular research最新文献

Background: Previous studies have demonstrated that statins can relieve inflammatory brain injury after intracerebral hemorrhage (ICH), but the mechanisms remain poorly characterized. This study aims to test whether simvastatin exerts an anti-inflammatory effect by regulating the proresolving mediators.

Methods: First, male Sprague-Dawley rats had an injection of 200 μL autologous blood. Then, rats were randomly divided into groups treated with simvastatin (i.p. 2 mg/kg) or vehicle. Next, all rats underwent pro-resolving mediator lipoxin A4 (LXA4) level detection, flow cytometric, immunofluorescence, brain edema measurement, neurological scoring and western blot analysis.

Results: We found that simvastatin significantly increased the plasma level of LXA4, an endogenous formyl-peptide receptor 2 (FPR2) agonist, in the early stage of ICH. Consistent with the effect of simvastatin, exogenous LXA4 administration also promoted apoptosis of the circulating neutrophils, reduced neutrophils brain infiltration, and ameliorated inflammatory brain injury after ICH. In addition, similar to simvastatin, exogenous LXA4 markedly decreased the level of phosphorylated p38 mitogen-activated protein kinase (MAPK) and the apoptosis-related proteins myeloid cell leukemia 1(Mcl-1)/Bax ratio (a decreased ratio represents the induction of apoptosis) in circulating neutrophils isolated from ICH rats. Notably, all of the aforementioned effects of simvastatin on ICH were significantly abolished by Boc-2, a selective antagonist of FPR2. Moreover, simvastatin led to a similar Mcl-1/Bax ratio reduction as SB203580 (a p38 MAPK inhibitor), but it was abolished by P79350 (a p38 MAPK agonist).

Conclusion: Collectively, these results suggest that simvastatin ameliorates ICH-mediated inflammatory brain injury, possibly by upregulating the level of pro-resolving mediator LXA4 and further stimulating the FPR2/p38 MAPK signaling pathway.

Background: Uric acid (UA) has both antioxidative and pro-oxidative properties. The study aimed to investigate the relationship between serum UA and hemorrhagic transformation (HT) after intravenous thrombolysis in patients with acute ischemic stroke.

Methods: The patients undergoing intravenous thrombolysis from two hospitals in China were retrospectively analyzed. HT was evaluated using computed tomography images reviewed within 24- 36h after thrombolysis. Symptomatic intracranial hemorrhage (sICH) was defined as HT accompanied by worsening neurological function. Multivariate logistic regression and spline regression models were performed to explore the relationship between serum UA levels and the risk of HT and sICH.

Results: Among 503 included patients, 60 (11.9%) were diagnosed with HT and 22 (4.4%) developed sICH. Patients with HT had significant lower serum UA levels than those without HT (245 [214-325 vs. 312 [256-370] μmol/L, p < 0.001). Multivariable logistic regression analysis indicated that patients with higher serum UA levels had a lower risk of HT (OR per 10-μmol/L increase 0.96, 95%CI 0.92-0.99, p = 0.015). Furthermore, multiple-adjusted spline regression models showed a Ushaped association between serum UA levels and HT (p < 0.001 for non-linearity). Similar results were present between serum UA and sICH. Restricted cubic spline models predicted the lowest risk of HT and sICH when the serum UA levels were 386μmol/L.

Conclusion: The data show the U-shaped relationship between serum UA levels and the risk of HT and sICH after intravenous thrombolysis.

Objective: To our knowledge, no previous studies have investigated the impact of stroke severity on the smoking paradox after intravenous thrombolysis (IVT). We aimed to explore the contribution of stroke severity to the association between smoking and stroke prognosis after IVT.

Methods: We enrolled consecutive patients who received IVT within 4.5 hours from stroke onset. A logistic regression model was used to estimate the unadjusted and adjusted odds ratios (ORs) with their 95% confidence intervals (CIs) for poor functional outcome and mortality at 3 months.

Results: Among patients with moderate stroke, smokers experienced a lower risk of 3-month poor outcomes than non-smokers (33.0% vs. 44.4%, unadjusted OR: 0.616; 95% CI: 0.402-0.945). However, among those with severe stroke, smokers had a higher risk of 3-month poor outcomes than non-smokers (81.6% vs. 55.9%, unadjusted OR: 3.496; 95% CI: 1.207-10.127). After adjustment, the negative correlation between smoking and 3-month poor outcome following IVT lost statistical significance in patients with moderate stroke (OR: 0.677 [95% CI: 0.418-1.097]). However, smoking remained a risk factor for 3-month poor outcomes in patients with severe stroke (OR: 4.216 [95% CI: 1.236-14.385]). We also observed a significant interaction between smoking and stroke severity with regard to the risk of poor functional outcomes (p=0.023). However, no such interaction influenced mortality (p=0.901).

Conclusion: Stroke severity affects the association between smoking and 3-month clinical functional outcomes following IVT.

Background and purpose: The purpose of this study was to show dynamic changes in carotid and vertebral artery using carotid Doppler ultrasonography (DUS) through a long-term follow- up exam, and determine their associations with stroke recurrence.

Methods: We consecutively enrolled stroke or transient ischemic attack (TIA) patients who had undergone DUS more than twice with intervals of three months or more. Stroke recurrence during follow-up was also investigated by reviewing medical records. Progress or regress of plaque was defined as more than 0.1 mm change from the initial scan with a semi-quantitative measurement. The development of new plaque was also regarded as plaque progress. Increased intima-media thickness and plaque presence were interpreted at the initial and follow-up scans. Factors related to progression or regression were analyzed. The relationship between plaque change and stroke recurrence was investigated.

Results: A total of 201 patients were enrolled (186 ischemic stroke patients and 15 TIA patients). There were 61 (30.3%) females. Their mean age was 64.2 ± 9.9 years. During a follow-up of 35.0 ± 22.6 (mean ± SD) months, plaque progress was observed in 92 (45.8%) and plaque regress in 13 (6.5%). Stroke recurred in 18 patients. Plaque progression showed no significant association with age, risk factors, statin use, or subtype. After adjustment of age, sex, diabetes, and stroke subtype, multiple logistic regression showed a significant association of plaque progression with stroke recurrence (odds ratio: 3.8, 95% confidence interval: 1.1 to 13.1, p = 0.034). Patients with plaque regress were significantly younger than those without plaque regress (57.8 years vs. 64.6 years, p = 0.041).

Conclusion: Plaque progression occurred in 46% of stroke or TIA patients. Plaque progression was significantly associated with clinical stroke recurrence. Plaque regressed in 6.5% of patients. Patients with regression were younger than those without.

Background: Retinal artery occlusion (RAO) is an emergency condition in both neurology and ophthalmology departments. However, RAO's management and visual outcome in different initial departments remain unclear. Therefore, we aimed to investigate the impact of the initial department on the management and prognosis of RAO.

Methods: Consecutive cases of RAO between January 2011 and December 2021 were retrospectively analyzed. The neurology and ophthalmology departments compared the baseline characteristics, relevant evaluation, and treatment. The primary outcome was the visual recovery rate. The secondary outcomes were newly diagnosed cardiovascular factors, concurrent stroke and new-onset cardiovascular events.

Results: A total of 74 RAO patients were included. The median age was 54 years, and 67.6% were male. 42 (56.8%) patients were admitted to the neurology department and 32 (43.2%) to the ophthalmology department. The visual recovery rate was higher in the neurology department than in the ophthalmology department, although the difference did not reach statistical significance (27.8 vs. 12.5%, p = 0.120). Risk factor evaluation and secondary prevention were taken more frequently in the neurology department (p < 0.001). Cardiovascular risk factors and concurrent stroke were all discovered in the neurology department. However, the incidence of new-onset cardiovascular events was similar between the two departments.

Conclusion: The study demonstrated that the visual prognosis of RAO was devastating regardless of the neurology and ophthalmology department. Given the admission delay, inadequate management, and high risk of cardiovascular risk factors and stroke, stroke centers should be recommended as initial admission departments for RAO patients.

Objective: Mechanical thrombectomy (MT) is an effective treatment for large vessel occlusion (LVO) with a high successful recanalization (SR) rate. However, MT fails in a proportion of patients, leading to poor clinical outcomes. We analyzed the factors associated with the failure of MT.

Methods: A total of 648 consecutive patients with MT were enrolled. MT failure was defined as 0,1, or 2a of modified Thrombolysis in Cerebral Infarction (mTICI) grade. Failed MTs were divided into 3 categories, reaching failure, passage failure, and recanalization failure (RF). Various factors in RF and SR groups were analyzed with 1: 1 propensity score matching.

Results: Failed MT was observed in 97 patients (14.3%). Among them, 69 patients (10.2% of the entire cohort, 71.1% of the failed MT group) were included in the RF group. Propensity matching analysis with 69 patients in each group showed that the RF group had a higher rate of residual intracranial atherosclerotic stenosis (ICAS) than the SR group (30.4% vs. 14.5% P = 0.003). The rates of 4 or more passages and no change of method were significantly higher in the RF group than in the SR group (34.8% vs. 13.0%; P = 0.001 and 28.9% vs. 8.7%; P = 0.001).

Conclusion: The failure rate for all of the MT was approximately 15%, and RF accounted for more than 70% of the failed MT. RF was associated with residual ICAS. In cases with RF, even in repeated attempts for recanalization, an alteration of the thrombectomy method should be considered.

Background: Carotid plaque is often an important factor in ischemic stroke after it changes from stable to vulnerable, and low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) are associated with plaque vulnerability. We aimed to investigate whether the LDL-c/HDL-c ratio, an easily available and novel biomarker, is associated with vulnerable plaques and enhances the warning effect on vulnerability compared to LDL-c or HDL-c alone.

Methods: We conducted a retrospective study of 187 patients with severe CAS admitted to the Department of Vascular Surgery at the Nanjing Drum Tower Hospital from January 2019 to July 2021. They were divided into a stable plaque group and a vulnerable plaque group according to carotid ultrasonography, carotid angiography (CTA), and plaque pathology. Baseline information was collected and compared between the two groups. Correlation analysis was used to determine the degree of correlation between clinical variables. Univariate and multifactor logistic regression analyses were used to examine independent risk factors for vulnerable plaque in patients with severe CAS. Receiver operating characteristic (ROC) curves were used to assess the capacity of LDL-c/HDL-c to predict the occurrence of vulnerable plaque.

Results: The age of the vulnerable plaque group was 68.12 ± 8.90 years, with 85 males (89.91%); the age of the stable plaque group was 68.77 ± 8.43 years, with 70 males (89.74%). Multivariate logistic regression analysis showed that LDL-c/HDL-c, smoking and diabetes were independent risk factors for vulnerable plaque (all P <0.05). The risk of vulnerable plaque was 4.78-fold greater in the highest LDL-c/HDL-c quartile (≥ 2.63) than in the lowest quartile (≤ 1.31) (P-trend <0.001), and the area under the ROC curve for LDL-c/HDL-c (AUC=0.681, P <0.001) was higher than that for LDL-c and HDL-c.

Conclusion: LDL-c/HDL-c, smoking and diabetes were independent risk factors for vulnerable plaque in patients with severe CAS, and LDL-c/HDL-c had a higher predictive value for the presence of vulnerable plaque compared with other lipid parameters.

Objective: We investigated the factors associated with cerebrospinal fluid (CSF) flow artifacts on fluid-attenuated inversion recovery imaging in patients with carotid artery (CA) stenosis.

Methods: Each CSF artifact grade was defined by comparing the highest intensity in a given region of interest (ROI) to those in reference ROIs, as follows: higher than the intensity of normal white matter in the centrum semiovale = 2 points; equal to or less than the white matter, and higher than CSF = 1 point; and equal to CSF = 0. CSF flow scores in eight sites were measured and added to the total score (0 -16). The prevalences of each finding, specifically white matter lesions, CA stenoses and brain atrophy, were compared using multivariate logistic regression models.

Results: We evaluated the findings in 54 patients with CA stenosis treated by CA stenting (CAS) and 200 adults with no history of neurological disorders (control group). Adjusted by stroke risk factors, a CSF flow score ≤ 11 was positively associated with CA stenosis, heart rate > 70 / min, and brain atrophy, and negatively with the female gender. The score was 12.8 ± 1.8 in the control group and 12.0 ± 2.0 in CA stenosis group after CAS, which was significantly higher than before CAS (10.4 ± 2.8, p<0.001).

Conclusion: The CSF flow score was associated with female gender, brain atrophy, heart rate, and severe CA stenosis, and was found to be elevated after revascularization.