Detecting prokaryote-specific gene and other bacterial signatures in thrombi from patients with acute ischemic stroke.

BACKGROUND AND PURPOSE: Microbial infection has been associated with thrombogenesis. This study aimed to detect bacterium-specific genes and other signatures in thrombi from patients with acute ischemic stroke and to relate these signatures to clinical characteristics. METHODS: Blood samples were collected before thrombectomy procedures, and thrombus samples were obtained during the procedure. Identification and classification of bacteria in the samples were accomplished using 16 S rRNA gene sequencing. Bacterium-specific structures were observed with transmission electron microscopy. Bacterium-specific biomarkers were detected through immunohistochemical staining. RESULTS: 16 S rRNA gene was detected in 32.1% of the thrombus samples from 81 patients. Bacillus (0.04% vs. 0.00046%, p = 0.003), Parabacteroides (0.20% vs. 0.09%, p = 0.029), Prevotella (1.57% vs. 0.38%, p = 0.010), Streptococcus (1.53% vs. 0.29%, p = 0.001), Romboutsia (0.18% vs. 0.0070%, p = 0.029), Corynebacterium (1.61% vs. 1.26%, p = 0.026) and Roseburia (0.53% vs. 0.05%, p = 0.005) exhibited significantly higher abundance in thrombi compared to arterial blood. Bacteria-like structures were observed in 22 (27.1%), while whole bacteria-like structures were observed in 7 (8.6%) thrombi under transmission electron microscopy. Immunohistochemical staining detected bacterium-specific monocyte/macrophage markers in 51 (63.0%) out of 81 thrombi. Logistic regression analysis indicated that alcohol consumption was associated with a higher bacteria burden in thrombi (odds ratio = 3.19; 95% CI, 1.10-9.27; p = 0.033). CONCLUSION: Bacterial signatures usually found in the oral cavity and digestive tract were detected in thrombi from patients with ischemic stroke. This suggests a potential involvement of bacterial infection in the development of thrombosis. Long-term alcohol consumption may potentially enhance this possibility.

Effects of intravenous rtPA in patients with minor stroke.

BACKGROUND: Whether minor ischemic stroke (MIS) patients can benefit from intravenous thrombolysis (IVT) remains controversial. The association between the efficacy of IVT and baseline National Institute of Health Stroke Scale (NIHSS) score is unclear in MIS, while the association in moderate and severe stroke is known. This study aimed to explore the effect of IVT in patients with MIS and analyze its efficacy in patients with different baseline NIHSS scores. METHODS: Patients with a NIHSS score ≤5 within 4.5 h of stroke onset were screened in 32 centers. Patients with and without IVT were matched to a ratio of 1:1 with propensity scores. An excellent outcome was defined as a modified Rankin Scale (mRS) score ≤1 at three months after stroke onset. Safety outcomes included mortality and symptomatic intracranial hemorrhage (sICH). Multivariate analysis was used to compute the adjusted odds ratio (OR) for excellent outcomes. The effect of IVT was further analyzed in subgroups according to the baseline NIHSS score. RESULTS: Of the 23,853 screened, 3336 patients with MIS who arrived at the hospital within 4.5 h of onset were included. The 1163 patients treated with IVT were matched with 1163 patients without IVT. IVT in minor strokes generated an adjusted OR of 1.38 (95% CI: 1.09-1.75, p = 0.009) for excellent outcomes. There were no significant differences in mortality (0.17% vs. 0.09%, p = 1.000) and sICH (0.69% vs. 0.86%, p = 0.813) between patients with and without IVT. Subgroup analysis showed that there was no significant effect of IVT in the baseline NIHSS 0-1 or 2-3 subgroups, with adjusted OR of 0.816 (95% CI 0.437-1.53, p = 0.525) and1.22 (95% CI 0.845-1.77, p = 0.287), respectively. In patients with NIHSS score of 4-5, IVT was significantly effective, with an adjusted OR of 1.53 (95% CI 1.02-2.30, p = 0.038). CONCLUSION: IVT can improve MIS outcomes. The risks of sICH and mortality did not increase, especially in patients with NIHSS scores 4 to 5, who could benefit from IVT significantly.

Overall, intravenous thrombolysis can improve the outcomes of patients with minor stroke.Minor stroke patients with a baseline NIHSS score of 4-5 can benefit the most from intravenous thrombolysis.

Dietary Flavonoid Intake and Carotid Calcification in Patients with Ischemic Stroke.

INTRODUCTION: Owing to the antioxidant and anti-inflammatory effects, flavonoids can influence the initiation and development of atherosclerosis, but the underlying mechanisms remain largely undetermined. This study aimed to evaluate the associations between dietary flavonoids and carotid calcification in patients with ischemic stroke. METHODS: This study screened consecutive patients with ischemic stroke via Nanjing Stroke Registry Program from February 2016 to April 2021. A semiquantitative food frequency questionnaire was used to evaluate dietary consumption of flavonoids and other nutritional components. Presence and degree of carotid calcification were determined according to Agatston scores on computer tomography angiography. Logistic regression was performed to evaluate the association between dietary flavonoids (total flavonoids, flavonols, flavones, flavanones, flavan-3-ols, anthocyanins, and isoflavones) and carotid calcification. RESULTS: Of the 601 enrolled patients, 368 (61.2%) were detected with carotid calcification. Patients with high intake of total flavonoids (the fifth quintile) had a 52% lower carotid calcification risk than those with low intake (the first quintile; odds ratio [OR] = 0.48; 95% confidence interval [CI], 0.26-0.90; p = 0.007 for trends) after adjusting for major confounders. Patients with high intake of flavan-3-ols (the fifth quintile) had a 51% lower carotid calcification risk than those with low intake (the first quintile; OR = 0.49; 95% CI, 0.25-0.97; p = 0.016 for trends). CONCLUSION: Dietary flavonoid intake is associated with carotid calcification, and, therefore, may influence the risk of stroke occurrence and recurrence.

Chronic gastritis may predict risk of cerebral small vessel disease.

BACKGROUND AND PURPOSE: Chronic gastritis, especially that caused by helicobacter pylori (HP) infection, has been associated with increased risk of ischemic stroke. But the relationship between chronic gastritis and cerebral small vessel disease (CSVD) remains largely undetermined. This study aimed to determine the potential predictors for CSVD, with chronic gastritis and its proxies as alternatives. METHOD: Patients aged 18 years or older with indications for electronic gastroscopy were enrolled. Presence of CSVD was evaluated with brain magnetic resonance imaging (MRI) results. Degree of CSVD was scored according to established criteria. Logistic regression analysis was used for identifying possible risk factors for CSVD. RESULTS: Of the 1191 enrolled patients, 757 (63.6%) were identified as with, and 434 (36.4%) as without CSVD. Multivariate analysis indicated that patients with chronic atrophic gastritis had an increased risk for CSVD than those without (adjusted odds ratio = 1.58; 95% CI, 1.08-2.32; P < 0.05). CONCLUSIONS: Chronic atrophic gastritis is associated with the presence of CSVD. We should routinely screen the presence of CSVD for patients with chronic atrophic gastritis.

Genotype analysis of rotaviruses isolated from children during a phase III clinical trial with the hexavalent rotavirus vaccine in China.

The oral hexavalent live human-bovine reassortant rotavirus vaccine (RV6) developed by Wuhan Institute of Biological Products Co., Ltd (WIBP) has finished a randomized, placebo-controlled phase III clinical trial in four provinces of China in 2021. The trail demonstrated that RV6 has a high vaccine efficacy against the prevalent strains and is safe for use in infants. During the phase III clinical trial (2019-2021), 200 rotavirus-positive fecal samples from children with RV gastroenteritis (RVGE) were further studied. Using reverse transcription-polymerase chain reaction and high-throughput sequencing, VP7 and VP4 sequences were obtained and their genetic characteristics, as well as the differences in antigenic epitopes of VP7, were analyzed in detail. Seven rotavirus genotypes were identified. The predominant rotavirus genotype was G9P [8] (77.0%), followed by prevalent strains G8P [8] (8.0%), G3P [8] (3.5%), G3P [9] (1.5%), G1P [8] (1.0%), G2P [4] (1.0%), and G4P [6] (1.0%). The amino acid sequence identities of G1, G2, G3, G4, G8, and G9 genotypes of isolates compared to the vaccine strains were 98.8%, 98.2%-99.7%, 88.4%-99.4%, 98.2%, 94.2%-100%, and 93.9%-100%, respectively. Notably, the vaccine strains exhibited high similarity in amino acid sequence, with only minor differences in antigenic epitopes compared to the Chinese endemic strains. This supports the potential application of the vaccine in preventing diseases caused by rotaviruses.

Intravascular ultrasonography assisted carotid artery stenting for treatment of carotid stenosis: Two case reports.

BACKGROUND: Digital subtraction angiography (DSA), the gold standard of cerebrovascular disease diagnosis, is limited in its diagnostic ability to evaluate arterial diameter. Intravascular ultrasonography (IVUS) has advantages in assessing stenosis and plaque nature and improves the evaluation and effectiveness of carotid artery stenting (CAS). CASE SUMMARY: Case 1: A 65-year-old man presented with a five-year history of bilateral lower limb weakness due to stroke. Physical examination showed decreased strength (5-/5) in both lower limbs. Carotid artery ultrasound, magnetic resonance angiography, and computed tomography angiography (CTA) showed a right proximal internal carotid artery (ICA) stenosis (70%-99%), acute cerebral infarction, and severe right ICA stenosis, respectively. We performed IVUS-assisted CAS to measure the stenosis and detected a low-risk plaque at the site of stenosis prior to stent implantation. Post-stent balloon dilatation was performed and postoperative IVUS demonstrated successful expansion and adherence. CTA six months postoperatively showed no significant increase in in-stent stenosis. Case 2: A 36-year-old man was admitted with a right common carotid artery (CCA) dissection detected by ultrasound. Physical examination showed no positive neurological signs. Carotid ultrasound and CTA showed lumen dilation in the proximal CCA with an intima-like structure and bulging in the proximal segment of the right CCA with strip-like low-density shadow (dissection or carotid web). IVUS-assisted DSA confirmed right CCA dissection. CAS was performed and intraoperative IVUS suggested a large residual false lumen. Post-stent balloon dilatation was performed reducing the false lumen. DSA three months postoperatively indicated good stent expansion with mild stenosis. CONCLUSION: IVUS aids decision-making during CAS by accurately assessing carotid artery wall lesions and plaque nature preoperatively, dissection and stenosis morphology intraoperatively, and visualizing and confirming CAS postoperatively.

Immunogenicity and safety of a new hexavalent rotavirus vaccine in Chinese infants: A randomized, double-blind, placebo-controlled phase 2 clinical trial.

Rotavirus remains a major cause of diarrhea among 5-y-old children, and vaccination is currently the most effective and economical measure. We conducted a randomized, double-blind, placebo-controlled phase II clinical trial designed to determine the dosage, immunogenicity, and safety profile of a novel hexavalent rotavirus vaccine. In total, 480 eligible healthy infants, who were 6-12 weeks of age at the time of randomization were randomly allocated (1:1:1) to receive 105.5 focus-forming unit (FFU) or 106.5FFU of vaccine or placebo on a 0, 28 and 56-d schedule. Blood samples were collected 28 d after the third dose to assess rotavirus immunoglobulin A (IgA) antibody levels. Adverse events (AEs) up to 28 d after each dose and serious adverse events (SAEs) up to 6 months after the third dose were recorded as safety measurements. The anti-rotavirus IgA seroconversion rate of the vaccine groups reached more than 70.00%, ranging from 74.63% to 76.87%. The postdose 3 (PD3) geometric mean concentrations (GMCs) of anti-rotavirus IgA among vaccine recipients ranged from 76.97 U/ml to 84.46 U/ml. At least one solicited AE was recorded in 114 infants (71.25%) in the high-dose vaccine group, 106 infants (66.25%) in the low-dose vaccine group and 104 infants (65.00%) in the placebo group. The most frequently solicited AE was fever. The novel oral hexavalent rotavirus vaccine was safe and immunogenic in infants support the conclusion to advance the candidate vaccine for phase 3 efficacy trials.

Association between dietary antioxidant capacity and atherosclerotic carotid stenosis in patients with ischemic stroke.

BACKGROUND AND PURPOSE: The aim of this study was to evaluate the relationship between dietary total antioxidant capacity (DTAC) and atherosclerotic carotid stenosis in patients with ischemic stroke. METHODS: Patients with acute ischemic stroke were consecutively enrolled. Daily food consumption was estimated by a semi-quantitative food frequency questionnaire (FFQ). DTAC was calculated based on classified food intake. Antioxidant potential value was measured by ferric-reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) methods. Evaluation of carotid artery stenosis was based on computed tomography angiography (CTA). Logistic regression was used to assess the relationship between DTAC and degree of carotid stenosis. RESULTS: Of the 608 enrolled, 232 patients (38.2%) had moderate or severe carotid stenosis. After adjusting for major confounding factors, FRAP (OR =0.640; 95% CI: 0.410-0.998; P =0.049) and ORAC (OR =0.625; 95% CI: 0.400-0.976; P =0.039) were associated with lower degree of carotid artery stenosis (third vs first tertile). Spearman analysis indicated that FRAP (r =-0.121, P =0.003) and ORAC (r =-0.147, P <0.001) were correlated with degree of carotid stenosis. CONCLUSIONS: DTAC may influence the initiation and development of atherosclerosis, and, therefore, the risk of ischemic stroke.

Impacts of stress hyperglycemia ratio on early neurological deterioration and functional outcome after endovascular treatment in patients with acute ischemic stroke.

Background and Purpose: Hyperglycemia has been associated with unfavorable outcome of acute ischemic stroke, but this association has not been verified in patients with endovascular thrombectomy treatment. This study aimed to assess the impact of stress hyperglycemia ratio on early neurological deterioration and favorable outcome after thrombectomy in patients with acute ischemic stroke. Methods: Stroke patients with endovascular thrombectomy in two comprehensive centers were enrolled. Early neurological deterioration was defined as ≥4 points increase of National Institutes of Health Stroke Scale (NIHSS) at 24 hours after endovascular procedure. Favorable outcome was defined as modified Rankin Scale (mRS) score of 0-2 at 90 days of stroke onset. Multivariate regression analysis was used to identify the predictors for early neurological deterioration and favorable outcome. Results: Among the 559 enrolled, 74 (13.2%) patients developed early neurological deterioration. The predictors for early neurological deterioration were high stress hyperglycemia ratio at baseline (OR =5.77; 95% CI, 1.878-17.742; P =0.002), symptomatic intracranial hemorrhage (OR =4.90; 95% CI, 2.439-9.835; P <0.001) and high NIHSS score after 24 hours (OR =1.11; 95% CI, 1.071-1.151; P <0.001). The predictors for favorable outcome were stress hyperglycemia ratio (OR =0.196, 95% CI, 0.077-0.502; P =0.001), age (OR =0.942, 95% CI, 0.909-0.977; P =0.001), NIHSS score 24 hours after onset (OR =0.757, 95% CI =0.693-0.827; P <0.001), groin puncture to recanalization time (OR =0.987, 95% CI, 0.975-0.998; P =0.025), poor collateral status before treatment (ASITN/SIR grade 0-3, OR =62.017, 95% CI, 25.920-148.382; P <0.001), successful recanalization (mTICI 2b or 3, OR =7.415, 95% CI, 1.942-28.313; P =0.001). Conclusion: High stress hyperglycemia ratio may be related to early neurological deterioration and decreased likelihood of favourable outcomes after endovascular thrombectomy in patients with acute ischemic stroke.

The Association between Migraine and Fetal-Type Posterior Cerebral Artery in Patients with Ischemic Stroke.

OBJECTIVE: The aim of the study was to determine if migraine is associated with fetal-type posterior cerebral artery (PCA) in patients with ischemic stroke. METHOD: In this cross-sectional study, patients with acute ischemic stroke were enrolled from two hospitals. The history of migraine headache was evaluated during a face-to-face interview. The variants of fetal-type PCA were assessed with MRA, CTA, or DSA. Patients with and without migraine were compared in terms of fetal-type PCA status and other clinic characteristics. Multivariate logistic regression analyses were performed to adjust for confounders and provide risk estimates for observed associations. RESULT: In 750 patients qualified for analysis, 85 (11.3%) were determined with migraine. Patients with migraine had a higher proportion of female gender (51.8% vs. 31.0%, p < 0.001), hypertension (72.9% vs. 57.7%, p = 0.007), and fetal-type PCA (36.5% vs. 20.1%, p = 0.001), while lower proportion of current smoking (25.9% vs. 38.3%, p = 0.025) than patients without migraine. National Institutes of Health Stroke Scale (NIHSS) score (3 vs. 2, p = 0.016) was also higher in migraineurs than in non-migraineurs. After adjustment for confounders, fetal-type PCA status was independently associated with migraine (odds ratio [OR] = 2.06; 95% confidence interval [CI], 1.25-3.38; p = 0.005). Other factors associated to migraine included female gender (OR = 2.03; 95% CI, 1.13-3.62; p = 0.017), hypertension (OR = 1.97; 95% CI, 1.17-3.34; p = 0.011), and NIHSS score (OR = 1.08; 95% CI, 1.01-1.16; p = 0.018). CONCLUSION: Migraine was associated with fetal-type PCA in patients with ischemic stroke. This finding supported the hypothesis that vascular mechanisms get involved in the migraine-stroke association.

Endothelial caveolin-1 regulates cerebral thrombo-inflammation in acute ischemia/reperfusion injury.

BACKGROUND: Thrombo-inflammation is an important checkpoint that orchestrates infarct development in ischemic stroke. However, the underlying mechanism remains largely unknown. Here, we explored the role of endothelial Caveolin-1 (Cav-1) in cerebral thrombo-inflammation. METHODS: The correlation between serum Cav-1 level and clinical outcome was analyzed in acute ischemic stroke patients with successful recanalization. Genetic manipulations by endothelial-specific adeno-associated virus (AAV) and siRNA were applied to investigate the effects of Cav-1 in thrombo-inflammation in a transient middle cerebral artery occlusion (tMCAO) model. Thrombo-inflammation was analyzed by microthrombosis formation, myeloid cell infiltration, and endothelial expression of adhesion molecules as well as inflammatory factors. FINDINGS: Reduced circulating Cav-1, with the potential to predict microembolic signals, was more frequently detected in recanalized stroke patients without early neurological improvement. At 24 h after tMCAO, serum Cav-1 was consistently reduced in mice. Endothelial Cav-1 was decreased in the peri-infarct region. Cav-1-/- endothelium, with prominent barrier disruption, displayed extensive microthrombosis, accompanied by increased myeloid cell inflammatory infiltration after tMCAO. Specific enhanced expression of endothelial Cav-1 by AAV-Tie1-Cav-1 remarkably reduced infarct volume, attenuated vascular hyper-permeability and alleviated thrombo-inflammation in both wild-type and Cav-1-/- tMCAO mice. Transcriptome analysis after tMCAO further designated Rxrg as the most significantly changed molecule resulting from the knockdown of Cav-1. Supplementation of RXR-γ siRNA reversed AAV-Tie1-Cav-1-induced amelioration of thrombo-inflammation without affecting endothelial tight junction. INTERPRETATION: Endothelial Cav-1/RXR-γ may regulate infarct volume and neurological impairment, possibly through selectively controlling thrombo-inflammation coupling, in cerebral ischemia/reperfusion. FUNDING: This work was supported by National Natural Science Foundation of China.

High-frequency repetitive transcranial magnetic stimulation (rTMS) protects against ischemic stroke by inhibiting M1 microglia polarization through let-7b-5p/HMGA2/NF-κB signaling pathway.

BACKGROUND: Microglia assume opposite phenotypes in response to ischemic brain injury, exerting neurotoxic and neuroprotective effects under different ischemic stages. Modulating M1/M2 polarization is a potential therapy for treating ischemic stroke. Repetitive transcranial magnetic stimulation (rTMS) held the capacity to regulate neuroinflammation and astrocytic polarization, but little is known about rTMS effects on microglia. Therefore, the present study aimed to examine the rTMS influence on microglia polarization and the underlying possible molecular mechanisms in ischemic stroke models. METHODS: Previously reported 10 Hz rTMS protocol that regulated astrocytic polarization was used to stimulate transient middle cerebral artery occlusion (MCAO) rats and oxygen and glucose deprivation/reoxygenation (OGD/R) injured BV2 cells. Specific expression levels of M1 marker iNOS and M2 marker CD206 were measured by western blotting and immunofluorescence. MicroRNA expression changes detected by high-throughput second-generation sequencing were validated by RT-PCR and fluorescence in situ hybridization (FISH) analysis. Dual-luciferase report assay and miRNA knock-down were applied to verify the possible mechanisms regulated by rTMS. Microglia culture medium (MCM) from different groups were collected to measure the TNF-α and IL-10 concentrations, and detect the influence on neuronal survival. Finally, TTC staining and modified Neurological Severity Score (mNSS) were used to determine the effects of MCM on ischemic stroke volume and neurological functions. RESULTS: The 10 Hz rTMS inhibited ischemia/reperfusion induced M1 microglia and significantly increased let-7b-5p level in microglia. HMGA2 was predicted and proved to be the target protein of let-7b-5p. HMGA2 and its downstream NF-κB signaling pathway were inhibited by rTMS. Microglia culture medium (MCM) collected from rTMS treated microglia contained lower TNF-α concentration but higher IL-10 concentration than no rTMS treated MCM, reducing ischemic volumes and neurological deficits of MCAO mice. However, knockdown of let-7b-5p by antagomir reversed rTMS effects on microglia phenotype and associated HMGA/NF-κB activation and neurological recovery. CONCLUSION: High-frequency rTMS could alleviate ischemic stroke injury through inhibiting M1 microglia polarization via regulating let-7b-5p/HMGA2/NF-κB signaling pathway in MCAO models.

Extracellular vesicles carrying proinflammatory factors may spread atherosclerosis to remote locations.

Most cells involved in atherosclerosis release extracellular vesicles (EVs), which can carry bioactive substances to downstream tissues via circulation. We hypothesized that EVs derived from atherosclerotic plaques could promote atherogenesis in remote locations, a mechanism that mimics the blood metastasis of cancer. Ldlr gene knockout (Ldlr KO) rats were fed on a high cholesterol diet and underwent partial carotid ligation to induce local atherosclerosis. EVs were separated from carotid artery tissues and downstream blood of carotid ligation by centrifugation. MiRNA sequencing and qPCR were then performed to detect miRNA differences in EVs from rats with and without induced carotid atherosclerosis. Biochemical analyses demonstrated that EVs derived from atherosclerosis could increase the expression of ICAM-1, VCAM-1, and E-selectin in endothelial cells in vitro. EVs derived from atherosclerosis contained a higher level of miR-23a-3p than those derived from controls. MiR-23a-3p could promote endothelial inflammation by targeting Dusp5 and maintaining ERK1/2 phosphorylation in vitro. Inhibiting EV release could attenuate atherogenesis and reduce macrophage infiltration in vivo. Intravenously administrating atherosclerotic plaque-derived EVs could induce intimal inflammation, arterial wall thickening and lumen narrowing in the carotids of Ldlr KO rats, while simultaneous injection of miR-23a-3p antagomir could reverse this reaction. The results suggested that EVs may transfer atherosclerosis to remote locations by carrying proinflammatory factors, particularly miR-23a-3p.

Venous Flow Profiles on Perfusion CT are Associated with Futile Recanalization After Thrombectomy.

Background and Purpose: Robust venous outflow (VO) reflects favourable tissue reperfusion in acute ischaemic stroke (AIS) patients with large vessel occlusion (LVO). We aimed to investigate the association of the venous outflow profile on computed tomographic perfusion (CTP) and futile recanalization in anterior circulation AIS patients with LVO after thrombectomy. Methods: This was a retrospective study of consecutive AIS patients due to anterior circulation LVO who underwent CTP before thrombectomy. Patients who achieved successful recanalization defined as a modified Thrombolysis in Cerebral Infarction (mTICI) score of 2b or 3 after thrombectomy were included. Based on the venous time-intensity curve of CTP, the peak time of venous outflow (PTV), total venous outflow time (TVT), and difference value of arteriovenous peak time (D-value) were recorded. A modified mRS score of 3-6 at 3 months was regarded as futile recanalization (FR). Logistic regression analysis was applied to assess risk factors for FR. We used receiver operating characteristic curves (ROCs) to evaluate the predictive value of venous outflow time parameters based on VO for FR. Results: Eighty patients were included; 35 (43.8%) achieved good functional outcomes, and 45 (56.3%) had unfavourable functional outcomes, that is, FR. Adjusting confounding factors, binary stepwise logistic regression analysis showed that delayed PTV was independently associated with FR (odds ratio, 1.374 [95% CI, 1.093-1.726], P = 0.007). ROCs indicated that PTV effectively predicted unfavourable outcomes at 3 months (area under the curve (AUC) = 0.729, p< 0.001). The combined model was a powerful predictor of FR with an AUC of 0.824 and a cut-off value of 0.631 (p< 0.001). Conclusion: Delayed PTV is independently related to FR in anterior circulation AIS patients with LVO achieving successful recanalization after thrombectomy. Our results highlight that the time of VO may be a potential marker for FR.

Cystatin C predicts futile recanalization in patients with acute ischemic stroke after endovascular treatment.

BACKGROUND: A previous study reported that cystatin C was related to acute ischemic stroke. The association between cystatin C and the clinical outcome in acute ischaemic stroke patients with successful recanalization after endovascular thrombectomy has rarely been reported. This study aimed to evaluate the association between cystatin C and futile recanalization in AIS patients who underwent endovascular thrombectomy. METHODS: We carried out a retrospective study of acute ischaemic stroke patients with anterior circulation proximal arterial occlusion who achieved complete arterial recanalization after mechanical thrombectomy from May 2017 to April 2020. The patients with complete recanalization were divided into a useful recanalization group and a futile recanalization group according to their 3-month modified Rankin scale score. FR was defined as a modified mRS score of 3-6 at 3 months. Logistic regression analysis was used to identify the risk factors for FR. Receiver operating characteristic curves were used to assess the predictive value of cystatin C for FR. RESULTS: Of 241 patients, 125 underwent futile recanalization and 116 underwent useful recanalization. Baseline serum cystatin C levels were higher in the futile recanalization group than in the useful recanalization group. After adjustment for potential confounding factors, multivariable adjusted regression models showed that cystatin C was an independent predictor of futile recanalization (odds ratio, 4.111 [95% CI 1.427-11.840], P = 0.009). Receiver operator characteristic (ROC) curve analysis indicated that the model combining cystatin C with other factors model effectively predicted unfavourable outcomes at 3 months (area under the curve = 0.782, p < 0.01). CONCLUSIONS: A higher level of cystatin C is associated with unfavourable outcomes at 3 months in anterior circulation acute ischaemic stroke patients with endovascular thrombectomy.

Increased Renal Dysfunction, Apoptosis, and Fibrogenesis Through Sympathetic Hyperactivity After Focal Cerebral Infarction.

Sympathetic nervous system plays an important role in secondary injury of diseases. Accumulating evidence has observed association between ischemic stroke and renal dysfunction, but the mechanisms are incompletely clear. In this study, we investigated whether sympathetic hyperactivity can cause the development of renal dysfunction, apoptosis, and fibrogenesis after focal cerebral infarction. To determine the renal consequences of focal cerebral ischemia, we subjected a mice model of transient middle cerebral artery occlusion (tMCAO) and examined systolic blood pressure, heart rate, renal structure and function, serum catecholamine, and cortisol levels, and the expression of active caspase-3 bcl-2, bax, and phosphorylated p38 MAPK after 8 weeks. We also analyzed the relationship between insular cortex infarction and acute kidney injury (AKI) in 172 acute anterior circulation ischemic stroke (ACIS) patients. Transient right middle cerebral artery occlusion induced sympathetic hyperactivity, renal dysfunction, upregulation of apoptosis, and fibrogenesis in kidneys of mice. Metoprolol treatment relieves the development of renal injury. Study in stroke patients demonstrated that insular cortex infarction, especially the right insular cortex infarction, is an independent risk factor of AKI. Focal cerebral ischemia in mice leads to the development of renal injury driven by sympathetic hyperactivity. Right insular cortex infarction is an independent risk factor of AKI in older patients. Understanding the brain-kidney interaction after stroke would have clinical implications for the treatment and overall patient outcome.

A Co-Doped Fe3O4 Nanozyme Shows Enhanced Reactive Oxygen and Nitrogen Species Scavenging Activity and Ameliorates the Deleterious Effects of Ischemic Stroke.

Acute ischemic stroke has become the major cause of mortality and disability worldwide. Following ischemic stroke, the reperfusion injury is mainly mediated by the burst of reactive oxygen and nitrogen species (RONS). Therefore, blocking the excessive production or removing RONS holds great promise as a potential therapeutic strategy. Herein, we developed a Co-doped Fe3O4 nanozyme that is capable of scavenging H2O2, O2•-, •NO, and ONOO- in vitro and in vivo and provides neuroprotection against ischemic stroke. In vitro experiments showed that pre-incubation with the Co-Fe3O4 nanozyme could prevent neurotoxicity and neuroinflammation induced by H2O2 or lipopolysaccharide, respectively, in HT22 cells. After intravenous administration, the Co-Fe3O4 nanozyme showed no signs of toxicity in peripheral organs of C57BL/6J mice, even after prolonged delivery for 4 weeks. In permanent photothrombotic stroke model and transient middle cerebral artery occlusion stroke model, the Co-Fe3O4 nanozyme specifically accumulated in the infarct rim at 72 h post-stroke and was endocytosed by neurons, astrocytes, microglia, and endothelial cells. Importantly, the Co-Fe3O4 nanozyme delivery reduced the infarct volume in both stroke models. The observation that the Co-Fe3O4 nanozyme was efficacious in two well-characterized ischemic stroke models provides strong evidence that it represents a powerful tool for targeting oxidative and nitrosative stress in the ischemic brain.

Delayed Stroke Treatment during COVID-19 Pandemic in China.

BACKGROUND: Social distance, quarantine, pathogen testing, and other preventive strategies implemented during CO-VID-19 pandemic may negatively influence the management of acute ischemic stroke (AIS). OBJECTIVE: The current study aimed to evaluate the impacts of COVID-19 pandemic on treatment delay of AIS in China. METHODS: This study included patients with AIS admitted in 2 hospitals in Jiangsu, China. Patients admitted before and after the COVID-19 pandemic outbreak (January 31, 2020, as officially announced by the Chinese government) were screened to collect sociodemographic data, medical history information, and symptom onset status from clinical medical records and compared for pre- (measured as onset-to-door time [ODT]) and posthospital delay (measured as door-to-needle time [DNT]). The influencing factors for delayed treatment (indicated as onset-to-needle time >4.5 h) were analyzed with multivariate logistic regression analysis. RESULTS: A total of 252 patients were included, of which 153 (60.7%) were enrolled before and 99 (39.3%) after the COVID-19 pandemic. ODT increased from 202 min (interquartile range [IQR] 65-492) before to 317 min (IQR 75-790) after the COVID-19 pandemic (p = 0.001). DNT increased from 50 min (IQR 40-75) before to 65 min (IQR 48-84) after the COVID-19 pandemic (p = 0.048). The proportion of patients with intravenous thrombolysis in those with AIS was decreased significantly after the pandemic (15.4% vs. 20.1%; p = 0.030). Multivariate logistic regression analysis indicated that patients after COVID-19 pandemic, lower educational level, rural residency, mild symptoms, small artery occlusion, and transported by other means than ambulance were associated with delayed treatment. CONCLUSIONS: COVID-19 pandemic has remarkable impacts on the management of AIS. Both pre- and posthospital delays were prolonged significantly, and proportion of patients arrived within the 4.5-h time window for intravenous thrombolysis treatment was decreased. Given that anti-COVID-19 measures are becoming medical routines, efforts are warranted to shorten the delay so that the outcomes of stroke could be improved.

Early Neurological Deterioration and Hypoperfusion Volume Ratio on Arterial Spin Labeling in Patients with Acute Ischemic Stroke.

BACKGROUND: Arterial spin labeling (ASL) is a magnetic resonance imaging (MRI) technique used to quantify cerebral blood perfusion by labeling blood water as it flows throughout the brain. Hypoperfusion volume ratio (HVR) can be calculated using proportional hypoperfusion volume on ASL-based cerebral blood flow (CBF). This study aimed to explore the relation between HVR and early neurological deterioration (END) in AIS patients. SUBJECTS AND METHODS: Patients with AIS were recruited consecutively, and ASL and regular MRI scans were performed. HVR was calculated from 1.5 and 2.5s post labeling delay (PLD) ASL-CBF maps. END was defined as ≥2 points increment of NIHSS within 72 hours of stroke onset. Univariate and multivariate analysis were used to evaluate the relation between HVR and END. Receiver operating characteristic (ROC) curves were used to determine the ability of HVR in predicting END. RESULTS: Of the 52 enrolled patients, 18 (34.5%) were determined with END. In patients with END, the median hypoperfusion volume was 20 mL [Inter Quartile Range)IQR, 6-72.5 mL] at 1.5s PLD, and 11.2 mL (IQR, 5.3-26 mL) at 2.5s PLD; Sixteen (88.9%) patients had HVR ≥50%, and 13 (72.2%) patients hypoperfusion volume at 2.5s PLD ASL were greater than diffusion-weighted imaging (DWI) infarct volume. In patients without END, median hypoperfusion volume was 7 mL (IQR, 4-30 mL) at 1.5s PLD, and 4 mL (IQR, 1.5-8.5 mL) at 2.5s; Eleven (32.4%) patients had HVR ≥50%, and 10 (29.4%) patients hypoperfusion volume at 2.5s PLD ASL were greater than DWI infarct volume. The proportion of HVR ≥50% and hypoperfusion volume >DWI infarct volume were more frequent in patients with END than patients without (all P<0.001). After adjusted for age, admission NIHSS, proportion of hypoperfusion volume > DWI infarct and arterial transit artifact (ATA) by logistic regression analysis, HVR ≥50% (OR=13.1, P=0.003) was an independent risk factor for END. ROC analysis demonstrated that the HVR could predict END with an area under the curve of 0.794 (P=0.001). CONCLUSIONS: HVR obtained from the 1.5 and 2.5s PLD ASL may be a useful predictor of END in AIS. The value of HVR may be a marker for hemodynamic impairments.