Neuroimaging of motor recovery after ischemic stroke - functional reorganization of motor network

The long-term motor outcome of acute stroke patients may be correlated to the reorganization of brain motor network. Abundant neuroimaging studies contribute to understand the pathological changes and recovery of motor networks after stroke. In this review, we summarized how current neuroimaging studies have increased understanding of reorganization and plasticity in post stroke motor recovery. Firstly, we discussed the changes in the motor network over time during the motor-activation and resting states, as well as the overall functional integration trend of the motor network. These studies indicate that the motor network undergoes dynamic bilateral hemispheric functional reorganization, as well as a trend towards network randomization. In the second part, we summarized the current study progress in the application of neuroimaging technology to early predict the post-stroke motor outcome. In the third part, we discuss the neuroimaging techniques commonly used in the post-stroke recovery. These methods provide direct or indirect visualization patterns to understand the neural mechanisms of post-stroke motor recovery, opening up new avenues for studying spontaneous and treatment-induced recovery and plasticity after stroke.

Quantitative evaluation of CTP derived time-density alterations versus CTP for collateral status prediction with stroke

BACKGROUND AND OBJECTIVES

Collateral status is a pivotal determinant of clinical outcomes in acute ischemic stroke (AIS); however, its evaluation can be challenging. We investigated the predictive value of CT perfusion (CTP) derived time and density alterations versus CTP for collateral status prediction in AIS.

METHODS

Consecutive patients with anterior circulation occlusion within 24 h were retrospectively included. Time-density curves of the CTP specified ischemic core, penumbra, and the corresponding contralateral unaffected brain were obtained. The collateral status was dichotomised into robust (4-5 scores) and poor (0-3 scores) using multiphase collateral scoring, as described by Menon et al.. Receiver operating characteristic curves and multivariable regression analysis were performed to assess the predictive ability of CTP-designated tissue time and density alterations, CTP for robust collaterals, and favourable outcomes (mRS score of 0-2 at 90 days).

RESULTS

One-hundred patients (median age, 68 years; interquartile range, 57-80 years; 61 men) were included. A smaller ischemic core, shorter peak time delay, lower peak density decrease, lower cerebral blood volume ratio, and cerebral blood flow ratio in the CTP specified ischemic core were significantly associated with robust collaterals (PFDR ≤ 0.004). The peak time delay demonstrated the highest diagnostic value (AUC, 0.74; P < 0.001) with 66.7 % sensitivity and 73.7 % specificity. Furthermore, the peak time delay of less than 8.5 s was an independent predictor of robust collaterals and favourable clinical outcomes.

CONCLUSIONS

Robust collateral status was significantly associated with the peak time delay in the ischemic core. It is a promising image marker for predicting collateral status and functional outcomes in AIS.

Safety, tolerability, and pharmacokinetic of HY0721 in Chinese healthy subjects: A first-in-human randomized, double-blind, placebo-controlled dose escalation phase I study

BACKGROUND

HY0721 is a novel inhibitor of sulfonylurea receptor 1-transient receptor potential melastatin 4 (SUR1-TRPM4) for the treatment of acute ischemic stroke. This study aimed to evaluate the safety, tolerability, and pharmacokinetic (PK) profiles of single and multiple intravenous administration of HY0721 in Chinese healthy subjects.

METHODS

The study enrolled 48 and 30 healthy volunteers in the single-ascending dose (SAD) cohort (20, 60, 120, 240, and 320 mg) and multiple-ascending dose (MAD) cohort (60, 120, and 160 mg/bid), respectively, to receive the corresponding dosage of HY0721 or placebo. Safety monitoring included but was not limited to recording adverse events (AEs), vital signs, electrocardiograms, and laboratory tests. The blood samples were collected from subjects to determine the concentrations of HY0721 for PK evaluation.

RESULTS

The administration of HY0721 showed good safety and tolerability up to 320 mg in the SAD study and up to 160 mg twice daily in the MAD study. The most common AE was injection site reaction, and no AE led to discontinuation of administration or subject dropout. The exposures of HY0721 increased greater than dose proportional manner at the dosages of 20 to 320 mg in the SAD study. A linear PK profile was observed following multiple doses ranging from 60 to 160 mg twice daily, with no evidence of accumulation. Additionally, the human effective dose of HY0721 was estimated to be 120 mg.

CONCLUSION

This study demonstrated the intravenous administration of HY0721 is safe and well-tolerated in Chinese healthy subjects and provided 60 to 160 mg b.i.d. as the recommended dosing range for further clinical trials.

TRIAL REGISTRATION

ChinaDrugTrials.Org.cn; No. CTR20202604, 18 December 2020.

Leukocyte counts and ratios as potential predictors of large vessel occlusion in acute ischemic stroke: A retrospective cohort study

Leukocyte counts and ratios are independent biomarkers to determine the severity and prognosis of acute ischemic stroke (AIS). In AIS, the connection between leukocytes and large vessel occlusion (LVO) is uncertain. This study aims to determine the relationship between the existence of LVO and leukocyte counts and ratios on admission to AIS. Patients were retrospectively evaluated within six hours of AIS starting between January 2019 and April 2023. On admission, blood specimens were collected, and leukocyte subtype counts were promptly analyzed. Computed tomography or digital subtraction angiography were utilized to verify the existence of LVO. Regression analysis and receiver operating characteristic (ROC) curves were employed to investigate the connections between the counts and ratios of leukocytes and the existence of LVO, as well as the discriminatory ability of these variables in predicting LVO. Total white blood cell (WBC) count, neutrophil count, and neutrophil-to-lymphocyte ratio (NLR) were substantially higher in the LVO existence group compared to the LVO absence group, whereas the ratio of eosinophils to neutrophils (ENR × 102) was lower (P < .001, respectively). Significant associations were observed between total WBC counts, neutrophil counts, NLR, and ENR × 102 and the existence of LVO (P < .001, respectively). Total WBC counts, neutrophil counts, NLR, and ENR × 102 had respective areas under the curves (AUC) of 0.730, 0.748, 0.704, and 0.680 for identifying LVO. Our results show that in AIS patients, the existence of LVO is independently associated with elevated total WBC and neutrophil counts, high NLR, and low ENR × 102 levels. Neutrophil and total WBC counts, as well as NLR and levels of ENR × 102, may serve as potential biomarkers for predicting LVO. Neuroinflammation, based on the existence of LVO, should be given particular attention in future investigations.

Green autofluorescence of the skin and fingernails is a novel biomarker for evaluating the risk for developing acute ischemic stroke

The only existing approach for assessing the risk of developing acute ischemic stroke (AIS) necessitates that individuals possess a strong understanding of their health status. Our research gathered compelling evidence in favor of our hypothesis, suggesting that the likelihood of developing AIS can be assessed by analyzing the green autofluorescence (AF) of the skin and fingernails. Utilizing machine learning-based analyses of AF images, we found that the area under the curve (AUC) for distinguishing subjects with three risk factors from those with zero, one, or two risk factors was 0.79, 0.76, and 0.75, respectively. Our research has revealed that green AF serves as an innovative biomarker for assessing the risk of developing AIS. Our method is objective, non-invasive, efficient, and economic, which shows great promise to boost a technology for screening natural populations for risk of developing AIS.

Subtyping treatment response of tirofiban in acute ischemic stroke based on neuroimaging features

In a previously published clinical trial, we demonstrated that tirofiban was effective and safe in acute ischemic stroke (AIS) patients who did not undergo early recanalization treatments. We aimed to evaluate neuroimaging characteristics and their clinical significance to guide tirofiban treatment. In this post hoc analysis, location of infarcts (anterior circulation stroke [ACS] vs. posterior circulation stroke [PCS]), degree of cerebral artery stenosis (≤69% vs. ≥70% or occlusion), total infarct volume, and ASPECTS were used to predict the treatment effects of tirofiban, defined as the proportions of excellent and favorable functional outcome (modified Rankin Scale [mRS] score of 0-1, 0-2) at 90 days. ACS patients were more likely to achieve excellent (OR 2.08; 95% CI 1.25-3.45; p = 0.004) and favorable functional outcome (OR 2.28; 95% CI 1.24-4.22; p = 0.008) when treated with tirofiban. However, there was no significant difference in PCS patients between tirofiban and the control group. For patients with severe stenosis (≥70% or occlusion), tirofiban treatment improved the proportion of good outcomes (OR 2.84; 95% CI 1.44-5.60; p = 0.002 for mRS 0-1; OR 2.42; 95% CI 1.22-4.77; p = 0.011 for mRS 0-2). Meanwhile, we found that tirofiban improved outcome in patients with ASPECTS 8-10 and was independent of total infarct volume. These findings support the hypothesis that patients with ACS and severe stenosis may be recommended for tirofiban treatment, which can be predicted independent of total infarct volume.

Multimodal Cardiac Imaging in the Assessment of Patients Who Have Suffered a Cardioembolic Stroke: A Review

Cardioembolic strokes account for 20-25% of all ischaemic strokes, with their incidence increasing with age. Cardiac imaging plays a crucial role in identifying cardioembolic causes of stroke, with early and accurate identification affecting treatment, preventing recurrence, and reducing stroke incidence. Echocardiography serves as the mainstay of cardiac evaluation. Transthoracic echocardiography (TTE) is the first line in the basic evaluation of structural heart disorders, valvular disease, vegetations, and intraventricular thrombus. It can be used to measure chamber size and systolic/diastolic function. Trans-oesophageal echocardiography (TOE) yields better results in identifying potential cardioembolic sources of stroke and should be strongly considered, especially if TTE does not yield adequate results. Cardiac computed tomography and cardiac magnetic resonance imaging provide better soft tissue characterisation, high-grade anatomical information, spatial and temporal visualisation, and image reconstruction in multiple planes, especially with contrast. These techniques are useful in cases of inconclusive echocardiograms and can be used to detect and characterise valvular lesions, thrombi, fibrosis, cardiomyopathies, and aortic plaques. Nuclear imaging is not routinely used, but it can be used to assess left-ventricular perfusion, function, and dimensions and may be useful in cases of infective endocarditis. Its use should be considered on a case-by-case basis. The accuracy of each imaging modality depends on the likely source of cardioembolism, and the choice of imaging approach should be tailored to individual patients.

Approach to diagnosis, evaluation, and treatment of generalized and nonlocal dysesthesia: A review

Dysesthesia is an abnormal sensation in the skin that occurs in the absence of any extraordinary stimulus or other primary cutaneous disorders, excluding any delusions or tactile hallucinations. Clinicians have characterized dysesthesias to include sensations such as burning, tingling, pruritus, allodynia, hyperesthesia, or anesthesia. The etiology and pathogenesis of various generalized dysesthesias is largely unknown, though many dysesthesias have been associated with systemic pathologies including malignancy, infection, autoimmune disorders, and neuropathies. Dermatologists are often the first-line clinicians for patients presenting with such cutaneous findings, thus it is crucial for these physicians to be able to methodically work-up generalized dysesthesias to build a working differential diagnosis, follow up with key labs and/or imaging, and offer patients evidence-based treatment to relieve their symptoms. This broad literature review is an attempt to centralize key studies, cases, and series to help guide dermatologists in their assessment and evaluation of complaints of abnormal cutaneous sensations.

Microbiota Metabolites and Immune Regulation Affect Ischemic Stroke Occurrence, Development, and Prognosis

The gut microbiota are not only related to the development and occurrence of digestive system disease, but also have a bidirectional relationship with nervous system diseases via the microbiota-gut-brain axis. At present, correlations between the gut microbiota and neurological diseases, including stroke, are one of the focuses of investigation and attention in the medical community. Ischemic stroke (IS) is a cerebrovascular disease accompanied by focal neurological deficit or central nervous system injury or death. In this review, we summarize the contemporary latest research on correlations between the gut microbiota and IS. Additionally, we discuss the mechanisms of gut microbiota implicated in IS and related to metabolite production and immune regulation. Moreover, the factors of gut microbiota that affecting IS occurrence, and research implicating the gut microbiota as potential therapeutic targets for IS, are highlighted. Our review highlights the evidential relationships and connections between the gut microbiota and IS pathogenesis and prognosis.

Neuroimaging Modalities Used for Ischemic Stroke Diagnosis and Monitoring

Strokes are one of the global leading causes of physical or mental impairment and fatality, classified into hemorrhagic and ischemic strokes. Ischemic strokes happen when a thrombus blocks or plugs an artery and interrupts or reduces blood supply to the brain tissue. Deciding on the imaging modality which will be used for stroke detection depends on the expertise and availability of staff and the infrastructure of hospitals. Magnetic resonance imaging provides valuable information, and its sensitivity for smaller infarcts is greater, while computed tomography is more extensively used, since it can promptly exclude acute cerebral hemorrhages and is more favorable speed-wise. The aim of this article was to give information about the neuroimaging modalities used for the diagnosis and monitoring of ischemic strokes. We reviewed the available literature and presented the use of computed tomography, CT angiography, CT perfusion, magnetic resonance imaging, MR angiography and MR perfusion for the detection of ischemic strokes and their monitoring in different phases of stroke development.

Prognostic Neuroimaging Biomarkers in Acute Vascular Brain Injury and Traumatic Brain Injury

Prognostic imaging biomarkers after acute brain injury inform treatment decisions, track the progression of intracranial injury, and can be used in shared decision-making processes with families. Herein, key established biomarkers and prognostic scoring systems are surveyed in the literature, and their applications in clinical practice and clinical trials are discussed. Biomarkers in acute ischemic stroke include computed tomography (CT) hypodensity scoring, diffusion-weighted lesion volume, and core infarct size on perfusion imaging. Intracerebral hemorrhage biomarkers include hemorrhage volume, expansion, and location. Aneurysmal subarachnoid biomarkers include hemorrhage grading, presence of diffusion-restricting lesions, and acute hydrocephalus. Traumatic brain injury CT scoring systems, contusion expansion, and diffuse axonal injury grading are reviewed. Emerging biomarkers including white matter disease scoring, diffusion tensor imaging, and the automated calculation of scoring systems and volumetrics are discussed.

Phenomic Studies on Diseases: Potential and Challenges

The rapid development of such research field as multi-omics and artificial intelligence (AI) has made it possible to acquire and analyze the multi-dimensional big data of human phenomes. Increasing evidence has indicated that phenomics can provide a revolutionary strategy and approach for discovering new risk factors, diagnostic biomarkers and precision therapies of diseases, which holds profound advantages over conventional approaches for realizing precision medicine: first, the big data of patients' phenomes can provide remarkably richer information than that of the genomes; second, phenomic studies on diseases may expose the correlations among cross-scale and multi-dimensional phenomic parameters as well as the mechanisms underlying the correlations; and third, phenomics-based studies are big data-driven studies, which can significantly enhance the possibility and efficiency for generating novel discoveries. However, phenomic studies on human diseases are still in early developmental stage, which are facing multiple major challenges and tasks: first, there is significant deficiency in analytical and modeling approaches for analyzing the multi-dimensional data of human phenomes; second, it is crucial to establish universal standards for acquirement and management of phenomic data of patients; third, new methods and devices for acquirement of phenomic data of patients under clinical settings should be developed; fourth, it is of significance to establish the regulatory and ethical guidelines for phenomic studies on diseases; and fifth, it is important to develop effective international cooperation. It is expected that phenomic studies on diseases would profoundly and comprehensively enhance our capacity in prevention, diagnosis and treatment of diseases.

Different types of percutaneous endovascular interventions for acute ischemic stroke

BACKGROUND

Acute ischemic stroke (AIS) is the abrupt reduction of blood flow to a certain area of the brain which causes neurologic dysfunction. Different types of percutaneous arterial endovascular interventions have been developed, but as yet there is no consensus on the optimal therapy for people with AIS.

OBJECTIVES

To compare the safety and efficacy of different types of percutaneous arterial endovascular interventions for treating people with AIS.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; Issue 4 of 12, 2022), MEDLINE Ovid (1946 to 13 May 2022), Embase (1947 to 15 May 2022), Science Citation Index Web of Science (1900 to 15 May 2022), Scopus (1960 to 15 May 2022), and China Biological Medicine Database (CBM; 1978 to 16 May 2022). We also searched the ClinicalTrials.gov trials register and the World Health Organization (WHO) International Clinical Trials Registry Platform to 16 May 2022.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing one percutaneous arterial endovascular intervention with another in treating adult patients who have a clinical diagnosis of AIS due to large vessel occlusion and confirmed by imaging evidence, including thrombo-aspiration, stent-retrieval thrombectomy, aspiration-retriever combined technique, and thrombus mechanical fragmentation.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed the literature searches, identified eligible trials, and extracted data. A third review author participated in discussions to reach consensus decisions when any disputes occurred. We assessed risk of bias and applied the GRADE approach to evaluate the quality of the evidence. The primary outcome was rate of modified Rankin Scale (mRS) of 0 to 2 at three months. Secondary outcomes included the rate of modified Thrombolysis In Cerebral Infarction (mTICI) of 2b to 3 postprocedure, all-cause mortality within three months, rate of intracranial hemorrhage on imaging at 24 hours, rate of symptomatic intracranial hemorrhage at 24 hours, and rate of procedure-related adverse events within three months.

MAIN RESULTS

Four RCTs were eligible. The current meta-analysis included two trials with 651 participants comparing thrombo-aspiration with stent-retrieval thrombectomy. We judged the quality of evidence to be high in both trials according to Cochrane's risk of bias tool RoB 2. There were no significant differences between thrombo-aspiration and stent-retrieval thrombectomy in rate of mRS of 0 to 2 at three months (risk ratio [RR] 0.97, 95% confidence interval [CI] 0.82 to 1.13; P = 0.68; 633 participants; 2 RCTs); rate of mTICI of 2b to 3 postprocedure (RR 1.01, 95% CI 0.95 to 1.07; P = 0.77; 650 participants; 2 RCTs); all-cause mortality within three months (RR 1.01, 95% CI 0.74 to 1.37; P = 0.95; 633 participants; 2 RCTs); rate of intracranial hemorrhage on imaging at 24 hours (RR 1.03, 95% CI 0.86 to 1.24; P = 0.73; 645 participants; 2 RCTs); rate of symptomatic intracranial hemorrhage at 24 hours (RR 0.90, 95% CI 0.49 to 1.68; P = 0.75; 645 participants; 2 RCTs); and rate of procedure-related adverse events within three months (RR 0.98, 95% CI 0.68 to 1.41; P = 0.90; 651 participants; 2 RCTs). Another two included studies reported no differences for the comparisons of combined therapy versus stent-retrieval thrombectomy or thrombo-aspiration. One RCT is ongoing.

AUTHORS' CONCLUSIONS

This review did not establish any difference in safety and effectiveness between the thrombo-aspiration approach and stent-retrieval thrombectomy for treating people with AIS. Furthermore, the combined group did not show any obvious advantage over either intervention applied alone.

Nanotechnology in Stroke: New Trails with Smaller Scales

Stroke is a leading cause of death, long-term disability, and socioeconomic costs, highlighting the urgent need for effective treatment. During acute phase, intravenous administration of recombinant tissue plasminogen activator (tPA), a thrombolytic agent, and endovascular thrombectomy (EVT), a mechanical intervention to retrieve clots, are the only FDA-approved treatments to re-establish cerebral blood flow. Due to a short therapeutic time window and high potential risk of cerebral hemorrhage, a limited number of acute stroke patients benefit from tPA treatment. EVT can be performed within an extended time window, but such intervention is performed only in patients with occlusion in a larger, anatomically more proximal vasculature and is carried out at specialty centers. Regardless of the method, in case of successful recanalization, ischemia-reperfusion injury represents an additional challenge. Further, tPA disrupts the blood-brain barrier integrity and is neurotoxic, aggravating reperfusion injury. Nanoparticle-based approaches have the potential to circumvent some of the above issues and develop a thrombolytic agent that can be administered safely beyond the time window for tPA treatment. Different attributes of nanoparticles are also being explored to develop a multifunctional thrombolytic agent that, in addition to a thrombolytic agent, can contain therapeutics such as an anti-inflammatory, antioxidant, neuro/vasoprotective, or imaging agent, i.e., a theragnostic agent. The focus of this review is to highlight these advances as they relate to cerebrovascular conditions to improve clinical outcomes in stroke patients.

A new machine learning algorithm with high interpretability for improving the safety and efficiency of thrombolysis for stroke patients: A hospital-based pilot study

Background

Thrombolysis is the first-line treatment for patients with acute ischemic stroke. Previous studies leveraged machine learning to assist neurologists in selecting patients who could benefit the most from thrombolysis. However, when designing the algorithm, most of the previous algorithms traded interpretability for predictive power, making the algorithms hard to be trusted by neurologists and be used in real clinical practice.

Methods

Our proposed algorithm is an advanced version of classical k-nearest neighbors classification algorithm (KNN). We achieved high interpretability by changing the isotropy in feature space of classical KNN. We leveraged a cohort of 189 patients to prove that our algorithm maintains the interpretability of previous models while in the meantime improving the predictive power when compared with the existing algorithms. The predictive powers of models were assessed by area under the receiver operating characteristic curve (AUC).

Results

In terms of interpretability, only onset time, diabetes, and baseline National Institutes of Health Stroke Scale (NIHSS) were statistically significant and their contributions to the final prediction were forced to be proportional to their feature importance values by the rescaling formula we defined. In terms of predictive power, our advanced KNN (AUC 0.88) outperformed the classical KNN (AUC 0.75, p = 0.0192 ).

Conclusions

Our preliminary results show that the advanced KNN achieved high AUC and identified consistent significant clinical features as previous clinical trials/observational studies did. This model shows the potential to assist in thrombolysis patient selection for improving the successful rate of thrombolysis.

Optimization of electrical stimulation for the treatment of lower limb dysfunction after stroke: A systematic review and Bayesian network meta-analysis of randomized controlled trials

OBJECTIVE

To compare the treatment effect of five electrical stimulation methods commonly used in the treatment of stroke patients with lower limb dysfunction.

METHODS

We implemented a systematic search of 3915 studies published up to January 2023 from eight databases and two clinical trial registries. First, two independent reviewers critically evaluated trial eligibility according to the inclusion and exclusion criteria. Next, they selected and extracted data. Then, they assessed the risk of bias. Pairwise meta-analysis and Bayesian network meta-analysis were conducted to estimate the effectiveness and ranking of the five electrical stimulation methods.

RESULTS

A total of 33 trials with a final total of 2246 subjects were included in the analysis. By combining the comprehensive Rehabilitation Treatment (RT), the treatment effects of using five electrical stimulation methods were surperior to those of using RT only. In the meantime, RT+transcranial Direct Current Stimulation(tDCS) and RT+Functional Electrical Stimulation(FES) could be the optimal electric stimulation schemes for restoring lower limb motor function(SMD 8.35, 95%CI [3.05, 13.34]/ SMD 5.64, 95%CI [3.68, 7.56]), improving balance (SMD 9.80, 95%CI [0.67, 20.93]/ SMD 6.54, 95%CI [3.85, 10.95]) and activities of daily living(SMD 18.95, 95%CI [0.401, 36.9]/ SMD 15.47, 95%CI [7.89, 22.75]), and the treatment effects would be even better using RT+FES+tDCS combination.

CONCLUSION

tDCS and FES superior to other electrical stimulation methods based on RT in the treatment of lower limb dysfunction after stroke.

The feasibility and accuracy of machine learning in improving safety and efficiency of thrombolysis for patients with stroke: Literature review and proposed improvements

In the treatment of ischemic stroke, timely and efficient recanalization of occluded brain arteries can successfully salvage the ischemic brain. Thrombolysis is the first-line treatment for ischemic stroke. Machine learning models have the potential to select patients who could benefit the most from thrombolysis. In this study, we identified 29 related previous machine learning models, reviewed the models on the accuracy and feasibility, and proposed corresponding improvements. Regarding accuracy, lack of long-term outcome, treatment option consideration, and advanced radiological features were found in many previous studies in terms of model conceptualization. Regarding interpretability, most of the previous models chose restrictive models for high interpretability and did not mention processing time consideration. In the future, model conceptualization could be improved based on comprehensive neurological domain knowledge and feasibility needs to be achieved by elaborate computer science algorithms to increase the interpretability of flexible algorithms and shorten the processing time of the pipeline interpreting medical images.

The robust UCATR algorithm enhances the specificity and sensitivity to detect the infarct of acute ischaemic stroke within 6 hours of onset via non-contrast computed tomography images

PROBLEM BACKGROUND

Early detection of acute ischemic stroke (AIS) may provide patients with benefits against harmful health and financial impacts. The use of non-contrast computed tomography images for early detect of the infarct remains controversial.

MATERIALS & METHODS

Here, we used the UCATR algorithm to extract the pixel values of the infarct and the corresponding contralateral healthy area as the control surface in each NCCT slice for the whole brain. Magnetic resonance imaging results were used to verify both areas. We found significant pathological changes in the infarct compared with the corresponding contralateral healthy area in each NCCT slice.

ATTAINED RESULTS

Our approach validated that NCCT can be used to detect the lesion area in the early stage of AIS.

CONCLUSIONS

With obvious advantages such as saving time and the ability to quantify the infarct volume, this approach could help more patients survive the fatal and irreversible pathological process of AIS and improve their quality of life after AIS treatment.

Diagnostic Value of Image Features of Magnetic Resonance Imaging in Intracranial Hemorrhage and Cerebral Infarction

This study aimed to investigate the differential diagnosis value of routine magnetic resonance imaging (MRI) and magnetic resonance diffusion-weighted imaging (DWI) in hyperacute intracranial hemorrhage (HICH) and hyperacute cerebral infarction (HCI). Fifty-five patients with HICH were set as group A, and 55 patients with HCI were selected as group B. All the patients underwent routine MRI and DWI examinations. The morphological distribution and signal characteristics (low, high, or mixed) of the lesions in the two groups were recorded. The diagnostic accuracy, sensitivity, and specificity of routine MRI and DWI were compared for distinguishing HICH and HCI. The results suggested that the lesions in patients with HICH were mainly manifested as mixed signals (40 cases), while those in patients with HCI showed high signals (48 cases). HICH occurred in the basal ganglia in 44 cases, in the brain stem in 6 cases, in the cerebellum in 4 cases, in the cerebral cortex in 0 cases, and in the corpus callosum in 1 case. HCI occurred in the basal ganglia area, brain stem, cerebellum, cerebral cortex, and corpus callosum in 5, 3, 35, 12, and 0 cases, respectively. The diagnostic accuracy, specificity, and sensitivity of DWI for HICH and HCI were significantly higher than those of routine MRI (P < 0.05). It was indicated that compared with routine MRI, DWI was more effective in the diagnosis of HICH and HCI, with clearer and more accurate images and better diagnostic performance.

MRI whole-lesion texture analysis on ADC maps for the prognostic assessment of ischemic stroke

Background

This study aims is to explore whether it is feasible to use magnetic resonance texture analysis (MRTA) in order to distinguish favorable from unfavorable function outcomes and determine the prognostic factors associated with favorable outcomes of stroke.

Methods

The retrospective study included 103 consecutive patients who confirmed unilateral anterior circulation subacute ischemic stroke by computed tomography angiography between January 2018 and September 2019. Patients were divided into favorable outcome (modified Rankin scale, mRS ≤ 2) and unfavorable outcome (mRS > 2) groups according to mRS scores at day 90. Two radiologists manually segmented the infarction lesions based on diffusion-weighted imaging and transferred the images to corresponding apparent diffusion coefficient (ADC) maps in order to extract texture features. The prediction models including clinical characteristics and texture features were built using multiple logistic regression. A univariate analysis was conducted to assess the performance of the mean ADC value of the infarction lesion. A Delong’s test was used to compare the predictive performance of models through the receiver operating characteristic curve.

Results

The mean ADC performance was moderate [AUC = 0.60, 95% confidence interval (CI) 0.49–0.71]. The texture feature model of the ADC map (tADC), contained seven texture features, and presented good prediction performance (AUC = 0.83, 95%CI 0.75–0.91). The energy obtained after wavelet transform, and the kurtosis and skewness obtained after Laplacian of Gaussian transformation were identified as independent prognostic factors for the favorable stroke outcomes. In addition, the combination of the tADC model and clinical characteristics (hypertension, diabetes mellitus, smoking, and atrial fibrillation) exhibited a subtly better performance (AUC = 0.86, 95%CI 0.79–0.93; P > 0.05, Delong’s).

Conclusion

The models based on MRTA on ADC maps are useful to evaluate the clinical function outcomes in patients with unilateral anterior circulation ischemic stroke. Energy obtained after wavelet transform, kurtosis obtained after Laplacian of Gaussian transform, and skewness obtained after Laplacian of Gaussian transform were identified as independent prognostic factors for favorable stroke outcomes.

Cerebral Ischemic Events: An Overlooked Complication of Transthyretin Cardiac Amyloidosis in Afro-Caribbean Patients

Aim

The link between transthyretin cardiac amyloidosis (CATTR), and cerebral ischemic events (CIE) has only been hinted at till now, impeding progress in patient management. We seek to evaluate the frequency and characteristics of CIE in Afro-Caribbean patients followed for CATTR at our institution.

Methods

In this single-center retrospective observational study, Afro-Caribbean patients followed for CATTR between July 2005 and October 2019 were included. Occurrence of CIE was investigated, and their cardioembolic origin determined. Analysis of patient characteristics was conducted according to CIE and CATTR profiles.

Results

Overall, 120 CATTR patients were included: 17 wild-type ATTR (14.2%), 73 ATTR-V122I (60.8%), and 22 ATTR-I107V (18.3%). Thirty-six patients (30.0%) presented with CIE, including three transient ischemic attacks and 33 permanent ischemic strokes (75.8% with a cardioembolic pattern). CIE was concomitant with CATTR diagnosis in 16 (16/36: 44.4%) patients, while 14 patients (14/36: 38.9 %) experienced CIE over a median CATTR follow-up of 2.0 years (min-max range: 0.8–4.4 years). CATTR-CIE patients presented with atrial fibrillation (66.7%), left atrial enlargement (77.8%), a CHA2DS2-VASc ≥ 3 (97.2%) and a high anticoagulant intake (75.0%). Multivariate analysis retained only a high CHA2DS2-VASc score as an independent predictor of CIE risk (Hazard Ratio [95% CI]: 12.03 [1.62–89.24]).

Conclusion

Concomitant CIE, and CATTR diagnosis, potentially carries a worse prognosis. A CHA2DS2-VASc score ≥3 seems to be a strong and independent predictive factor of CIE in CATTR patients. Further studies are needed to assess the efficacy and timeliness of anticoagulation in CATTR patients, independently of atrial fibrillation.

Longitudinal Variations of CDC42 in Patients With Acute Ischemic Stroke During 3-Year Period: Correlation With CD4+ T Cells, Disease Severity, and Prognosis

Objective

Cell division cycle 42 (CDC42) modulates CD4⁺ T-cell differentiation, blood lipids, and neuronal apoptosis and is involved in the pathogenesis of acute ischemic stroke (AIS); however, the clinical role of CDC42 in AIS remains unanswered. This study aimed to evaluate the expression of CDC42 in a 3-year follow-up and its correlation with disease severity, T helper (Th)1/2/17 cells, and the prognosis in patients with AIS.

Methods

Blood CDC42 was detected in 143 patients with AIS at multiple time points during the 3-year follow-up period and in 70 controls at admission by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). In addition, blood Th1, Th2, and Th17 cells and their secreted cytokines (interferon-γ (IFN-γ), interleukin-4 (IL-4), and interleukin-17A (IL-17A)) in patients with AIS were detected by flow cytometry and enzyme-linked immunosorbent assay (ELISA), respectively.

Results

Compared with controls (p < 0.001), CDC42 was reduced in patients with AIS. CDC42 was negatively correlated with the National Institutes of Health Stroke Scale (NIHSS) score (p < 0.001), whereas, in patients with AIS (all p < 0.050), it was positively associated with Th2 cells and IL-4 but negatively correlated with Th17 cells and IL-17A. CDC42 was decreased from admission to 3 days and gradually increased from 3 days to 3 years in patients with AIS (P<0.001). In a 3-year follow-up, 24 patients with AIS recurred and 8 patients died. On the 3rd day, 7th day, 1st month, 3rd month, 6th month, 1st year, 2nd year, and 3rd year, CDC42 was decreased in recurrent patients than that in non-recurrent patients (all p < 0.050). CDC42 at 7 days (p = 0.033) and 3 months (p = 0.023) was declined in reported deceased patients than in survived patients.

Conclusion

CDC42 is used as a biomarker to constantly monitor disease progression and recurrence risk of patients with AIS.

Impact of dose reduction and iterative model reconstruction on multi-detector CT imaging of the brain in patients with suspected ischemic stroke

Non-contrast cerebral computed tomography (CT) is frequently performed as a first-line diagnostic approach in patients with suspected ischemic stroke. The purpose of this study was to evaluate the performance of hybrid and model-based iterative image reconstruction for standard-dose (SD) and low-dose (LD) non-contrast cerebral imaging by multi-detector CT (MDCT). We retrospectively analyzed 131 patients with suspected ischemic stroke (mean age: 74.2 ± 14.3 years, 67 females) who underwent initial MDCT with a SD protocol (300 mAs) as well as follow-up MDCT after a maximum of 10 days with a LD protocol (200 mAs). Ischemic demarcation was detected in 26 patients for initial and in 64 patients for follow-up imaging, with diffusion-weighted magnetic resonance imaging (MRI) confirming ischemia in all of those patients. The non-contrast cerebral MDCT images were reconstructed using hybrid (Philips “iDose4”) and model-based iterative (Philips “IMR3”) reconstruction algorithms. Two readers assessed overall image quality, anatomic detail, differentiation of gray matter (GM)/white matter (WM), and conspicuity of ischemic demarcation, if any. Quantitative assessment included signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) calculations for WM, GM, and demarcated areas. Ischemic demarcation was detected in all MDCT images of affected patients by both readers, irrespective of the reconstruction method used. For LD imaging, anatomic detail and GM/WM differentiation was significantly better when using the model-based iterative compared to the hybrid reconstruction method. Furthermore, CNR of GM/WM as well as the SNR of WM and GM of healthy brain tissue were significantly higher for LD images with model-based iterative reconstruction when compared to SD or LD images reconstructed with the hybrid algorithm. For patients with ischemic demarcation, there was a significant difference between images using hybrid versus model-based iterative reconstruction for CNR of ischemic/contralateral unaffected areas (mean ± standard deviation: SD_IMR: 4.4 ± 3.1, SD_iDose: 3.5 ± 2.3, P < 0.0001; LD_IMR: 4.6 ± 2.9, LD_iDose: 3.2 ± 2.1, P < 0.0001).  In conclusion, model-based iterative reconstruction provides higher CNR and SNR without significant loss of image quality for non-enhanced cerebral MDCT.

Dengzhanxixin Injection Ameliorates Cognitive Impairment Through a Neuroprotective Mechanism Based on Mitochondrial Preservation in Patients With Acute Ischemic Stroke

Acute ischemic stroke (AIS) is a global health burden and cognitive impairment is one of its most serious complication. Adequate interventions for AIS may have the potential to improve cognitive outcomes. In the present study, we selected Erigeron breviscapus (Vaniot) Hand.-Mazz. injection (Dengzhanxixin injection, DZXI), a widely used Chinese herbal injection, in contrast to edaravone as the positive control drug to test its potential to ameliorates neurological and cognitive impairments caused by AIS. We performed a 2-week randomized trial with these two drugs in AIS patients presenting mild to moderate cognitive impairments. Neuropsychological tests and MRI examinations showed that DZXI attenuated the neurological and cognitive impairments of patients and protected the grey matter in specific regions from ischemic damage. Notably, DZXI exerted better effects than edaravone in some neuropsychological tests, probably due to the protective effect of DZXI on grey matter. To explore the therapeutic mechanisms, we carried out an experiment with a middle cerebral artery occlusion rat model. We found that DZXI decreased the infarct volume and increased the survival of neuronal cells in the ischemic penumbra; furthermore, DZXI modulated the mitochondrial respiratory chain process and preserved the mitochondrial structure in the brain tissue. Overall, our data suggested that the administration of DZXI is effective at ameliorating neurological and cognitive impairments in AIS, and the underlying mechanisms are related to the protective effects of DZXI on cerebral neurons and neuronal mitochondria.

Systematic Study of Crucial Transcription Factors of Coptidis rhizoma Alkaloids against Cerebral Ischemia-Reperfusion Injury

Coptidis rhizoma alkaloids (CRAs), extracted from Coptidis rhizoma, have been indicated to play important neuroprotective roles, but the mechanism underlying has not been determined, especially from the perspective of transcription factors (TFs). In this study, crucial TFs involved in the protective activity of CRA were revealed based on RNA-Seq technology, proteomics, and network pharmacological analysis of the effects of CRA on middle cerebral artery occlusion-mediated cerebral ischemia-reperfusion (I/R) injury. Importantly, CRA significantly reduced the infarction rate and neurological deficiency score. Moreover, CRA significantly decreased the levels of TNF-α, MCP-1, and IL-1β. In addition, seven TFs, including Ncor1, Smad1, Bhlhe41, Stat3, Sp100, Satb2, and Lrpprc, were found to be crucial TFs, and five of these TFs were associated with inflammation. Furthermore, eight compounds in CRA were associated with the identified TFs through network pharmacological analysis. The alteration of Lrpprc and Sabt2 was further confirmed by measuring their downstream genes, including Pigg, Hhatl, Wdr77, Mpped1, Arpp21, Ppfia3, Rims1, and Cacna2d1 by reverse transcriptase polymerase chain reaction. Thus, these seven TFs may be important targets in CRA-mediated protection against I/R injury. This research provides a new view of the protective effect of CRA against cerebral I/R injury and reveals new therapeutic targets for treating cerebral ischemia.

Mechanism of ARPP21 antagonistic intron miR-128 on neurological function repair after stroke

OBJECTIVE

Stroke is a cerebrovascular disorder that often causes neurological function defects. ARPP21 is a conserved host gene of miR-128 controlling neurodevelopmental functions. This study investigated the mechanism of ARPP21 antagonistic intron miR-128 on neurological function repair after stroke.

METHODS

Expressions of ARPP21 and miR-128 in stroke patients were detected. The mouse neurons and astrocytes were cultured in vitro and treated with oxygen-glucose deprivation (OGD). The OGD-treated cells were transfected with pc-ARPP21 and miR-128 mimic. The proliferation of astrocytes, and the apoptosis of neurons and astrocytes were detected, and inflammatory factors of astrocytes were measured. The binding relationship between miR-128 and CREB1 was verified. The rat model of middle cerebral artery occlusion (MCAO) was established. ARPP21 expression in model rats was detected. The effects of pc-ARPP21 on neuron injury, brain edema volume, and cerebral infarct in rats were observed.

RESULTS

ARPP21 expression was downregulated and miR-128 expression was upregulated in stroke patients. pc-ARPP21 facilitated the proliferation of astrocytes and inhibited apoptosis of neurons and astrocytes, and reduced inflammation of astrocytes. miR-128 mimic could reverse these effects of pc-ARPP21 on neurons and astrocytes. miR-128 targeted CREB1 and reduced BDNF secretion. In vitro experiments confirmed that ARPP21 expression was decreased in MCAO rats, and pc-ARPP21 promoted neurological function repair after stroke.

CONCLUSION

ARPP21 upregulated CREB1 and BDNF expressions by antagonizing miR-128, thus inhibiting neuronal apoptosis and promoting neurological function repair after stroke. This study may offer a novel target for the management of stroke.

Emergency Care of Patients with Acute Ischemic Stroke

Stroke is a leading cause of morbidity and mortality and a major cause of long-term disability. Management of acute ischemic stroke in the first hours is critical to patient outcomes. This review provides an overview of acute ischemic stroke management, with a focus on the golden hour. Additional topics discussed include prehospital considerations and initial evaluation of the patient with history, examination, and imaging as well as treatment options, including thrombolysis and endovascular therapy.

Krizsan A, Forgács A, Berényi E, Balkay L. Effect of grey-level discretization on texture feature on different weighted MRI images of diverse disease groups

Purpose

Many studies of MRI radiomics do not include the discretization method used for the analyses, which might indicate that the discretization methods used are considered irrelevant. Our goals were to compare three frequently used discretization methods (lesion relative resampling (LRR), lesion absolute resampling (LAR) and absolute resampling (AR)) applied to the same data set, along with two different lesion segmentation approaches.

Methods

We analyzed the effects of altering bin widths or bin numbers for the three different sampling methods using 40 texture indices (TIs). The impact was evaluated on brain MRI studies obtained for 71 patients divided into three different disease groups: multiple sclerosis (MS, N = 22), ischemic stroke (IS, N = 22), cancer patients (N = 27). Two different MRI acquisition protocols were considered for all patients, a T2- and a post-contrast 3D T1-weighted MRI sequence. Elliptical and manually drawn VOIs were employed for both imaging series. Three different types of gray-level discretization methods were used: LRR, LAR and AR. Hypothesis tests were done among all diseased and control areas to compare the TI values in these areas. We also did correlation analyses between TI values and lesion volumes.

Results

In general, no significant differences were reported in the results when employing the AR and LAR discretization methods. It was found that employing 38 TIs introduced variation in the results when the number of bin parameters was altered, suggesting that both the degree and direction of monotonicity between each TI value and binning parameters were characteristic for each TI. Furthermore, while TIs were changing with altering binning values, no changes correlated to neither disease nor the MRI sequence. We found that most indices correlated weakly with the volume, while the correlation coefficients were independent of both diseases analyzed and MR contrast. Several cooccurrence-matrix based texture parameters show a definite higher correlation when employing the LRR discretization method However, with the best correlations obtained for the manually drawn VOI. Hypothesis tests among all disease and control areas (co-lateral hemisphere) revealed that the AR or LAR discretization techniques provide more suitable texture features than LRR. In addition, the manually drawn segmentation gave fewer significantly different TIs than the ellipsoid segmentations. In addition, the amount of TIs with significant differences was increasing with increasing the number of bins, or decreasing bin widths.

Conclusion

Our findings indicate that the AR discretization method may offer the best texture analysis in MR image assessments. Employing too many bins or too large bin widths might reduce the selection of TIs that can be used for differential diagnosis. In general, more statistically different TIs were observed for elliptical segmentations when compared to the manually drawn VOIs. In the texture analysis of MR studies, studies and publications should report on all important parameters and methods related to data collection, corrections, normalization, discretization, and segmentation.

Evaluation of Zhilong Huoxue Tongyu capsule in the treatment of acute cerebral infarction: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Zhilong Huoxue Tongyu capsule (ZL) is a Chinese patent medicine and used for the treatment of acute cerebral infarction (ACI) and its clinical application has gradually been widely recognized in China. However, the effects of ZL for patients with ACI have never been systematically evaluated.

PURPOSE

A systematic review and meta-analysis was performed to evaluate the efficacy of ZL in ACI.

STUDY DESIGN

A systematic review and meta-analysis of randomized clinical trials (RCTs).

MATERIALS AND METHODS

A systematic review and meta-analysis were performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. The comprehensive literature search was accomplished in 6 electronic databases to find relevant randomized controlled trials from their inception until October 31, 2020. The Cochrane Handbook for Systematic Reviews of Interventions was used for methodological quality and independent evaluation. Review Manager 5.3 was used to analyze all the data obtained. The Clinical Effective Rate (CER) was the primary outcome, and the National Institutes of Health Stroke Score (NIHSS), Barthel Index (BI), and Modified Rankin Scale (MRS) were the secondary outcomes.

RESULTS

Seven clinical studies recruiting 571 eligible patients were included in this meta-analysis. The results of meta-analysis suggested that compared with conventional treatment alone, ZL combined with conventional treatment significantly improved CER (RR = 1.20, 95% CI: 1.12-1.29, p < 0.00001), decrease National Institutes of Health Stroke Scale Score (NIHSS) (MD = -2.60, 95% CI: -3.41-1.79, p < 0.00001), Barthel Index (BI) (MD = -9.75, 95% CI: 7.15-12.36, p < 0.00001) and Modified Rankin Scale (MRS) (MD = -0.57, 95% CI: -0.84-0.30, p < 0.00001). There were no reported adverse events in the studies. Most results were robust and the quality of evidence was from moderate to low.

CONCLUSION

ZL combined with conventional treatment can improve the short-term outcomes of ACI patients, indicating ZL is a promising treatment choice for ACI and may be used as adjunctive treatment to the conventional treatment of ACI. However, due to the limitations of included clinical trials, high-quality clinical trials with longer follow-ups are still needed to further assess the effectiveness and safety of ZL for ACI patients.

Compound Dan Zhi tablet attenuates experimental ischemic stroke via inhibiting platelet activation and thrombus formation

BACKGROUND

Compound Dan Zhi tablet (DZT) is a commonly used traditional Chinese medicine formula. It has been used for the treatment of ischemic stroke for many years in clinical. However, its pharmacological mechanism is unclear.

PURPOSE

The aim of the current study was to understand the protective effects and underlying mechanisms of DZT on ischemic stroke.

METHODS

Fifteen representative chemical markers in DZT were determined by ultra-performance liquid chromatography coupled with tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS). The protective effect of DZT against ischemic stroke was studied in a rat model of middle cerebral artery occlusion (MCAO), and the mechanism was further explored through a combination of network pharmacology and experimental verification.

RESULTS

Quantitative analysis showed that the contents of phenolic acids, furan sulfonic acids, tanshinones, flavonoids, saponins and phthalides in DZT were calculated as 7.47, 0.788, 0.627, 0.531 and 0.256 mg/g, respectively. Phenolic acids were the most abundant constituents. Orally administered DZT (1.701 g kg^-1) significantly alleviated the infarct size and neurological scores in MCAO rats. The network analysis predicted that 53 absorbed active compounds in DZT-treated plasma targeted 189 proteins and 47 pathways. Ten pathways were associated with anti-platelet activity. In further experiments, DZT (0.4 and 0.8 mg mL^-1) markedly inhibited in vitro prostaglandin G/H synthase 1 (PTGS1) activity. DZT (0.4 and 0.8 mg mL^-1) significantly inhibited in vitro platelet aggregation in response to ADP or AA. DZT (113 and 226 mg kg^-1, p.o.) also produced a marked inhibition of ADP- or AA-induced ex vivo platelet aggregation with a short duration of action. DZT decreased the level of thromboxane A₂ (TXA₂) in MCAO rats. In the carrageenan-induced tail thrombosis model and ADP-induced acute pulmonary thromboembolism mice model, DZT (113 and 226 mg kg^-1, p.o.) prevented thrombus formation. Importantly, DZT (113 and 226 mg kg^-1, p.o.) exhibited a low bleeding liability.

CONCLUSION

DZT protected against cerebral ischemic injury. The inhibition of TXA₂ level, platelet aggregation and thrombosis formation might involve in the protective mechanism.

Visualising brain capillaries in magnetic resonance images via supramolecular self-assembly

We report the supramolecular self-assembly of one fluorescein and three Gd-chelate conjugated 8-arm polyethylene glycols (8-arm PEG-FGd₃) for visualising the capillaries of the brain in magnetic resonance imaging (MRI).

MRI characteristics in acute ischemic stroke patients with preceding direct oral anticoagulant therapy as compared to vitamin K antagonists

Background

Despite the utility of neuroimaging in the diagnostic and therapeutic management of patients with acute ischemic stroke (AIS), imaging characteristics in patients with preceding direct oral anticoagulants (DOAC) compared to vitamin K antagonists (VKA) have hardly been described. We aimed to determine presence of large vessel occlusion (LVO), thrombus length, infarction diameter, and occurrence of hemorrhagic transformation in AIS patients with preceding DOAC as compared to VKA therapy.

Methods

Using a prospectively collected cohort of AIS patients, we performed univariate and multivariable regression analyses regarding imaging outcomes. Additionally, we provide a sensitivity analysis for the subgroup of patients with confirmed therapeutic anticoagulation.

Results

We included AIS in patients with preceding DOAC (N = 75) and VKA (N = 61) therapy, median age 79 (IQR 70–83), 39% female. Presence of any LVO between DOAC and VKA patients (29.3% versus 37.7%, P = 0.361), and target LVO for endovascular therapy (26.7% versus 27.9%, P = 1.0) was equal with a similar occlusion pattern. DOAC as compared to VKA were associated with a similar rate of target LVO for EVT (aOR 0.835, 95% CI 0.368–1.898). The presence of multiple lesions and characteristics of the thrombus were similar in DOAC and VKA patients. Acute ischemic lesion diameter in real world patients was equal in patients taking DOAC as compared to VKA. Lesion diameter in VKA patients (median 13 mm, IQR 6–26 versus median 20 mm, IQR 7–36, P = 0.001), but not DOAC patients was smaller in the setting of confirmed therapeutic VKA. The frequency of radiological hemorrhagic transformation and symptomatic intracranial hemorrhage in OAC patients was low. Sensitivity analysis considering only patients with confirmed therapeutic anticoagulation did not change any of the results.

Conclusion

Preceding DOAC treatment showed equal rates of LVO and infarct size as compared to VKA in AIS patients. This study adds to the knowledge of imaging findings in AIS patients with preceding anticoagulation.

Nonatrial Fibrillation was Associated With Early Neurological Improvement After Intravenous Thrombolysis With rt-PA in Patients With Acute Ischemic Stroke

BACKGROUND

Intravenous thrombolysis is the only approved pharmacological treatment for acute ischemic stroke (AIS) patients, but the immediate response to thrombolysis varies by patient.

OBJECTIVE

To investigate the factors associated with early neurological improvement (ENI) after the administration of intravenous recombinant tissue plasminogen activator (rt-PA) treatment to AIS patients within 4.5 hours of onset.

METHODS

Demographics, onset to treatment time, risk factors, and clinical and laboratory data of 209 AIS patients undergoing intravenous rt-PA therapy at a Chinese hospital between January 2013 and August 2016 were retrospectively analyzed. The National Institutes of Health Stroke Scale (NIHSS) score was recorded before thrombolytic therapy, 24 hours after the treatment, and 7 days after the treatment to evaluate the recovery of neurological function. ENI was defined as a ≥4-point decrease in NIHSS score compared with baseline or a score of 0 or 1 at 24 hours and 7 days. A multivariate logistic regression analysis was performed to assess the outcomes.

RESULTS

Of the 209 AIS patients treated by intravenous thrombolysis with rt-PA, low-density lipoprotein (LDL) levels were significantly lower (P<0.05) in patients with ENI. The multivariable analysis showed that non-atrial fibrillation (AF) was independently associated with ENI at 24 hours and 7 days after thrombolysis. An overall 40.3% non-AF patients had ENI 24 hours after thrombolysis (odds ratio=2.501, 95% confidence interval: 1.204-5.198; P=0.014), and 65.9% non-AF patients had ENI 7 days after thrombolysis (odds ratio=2.953, 95% confidence interval: 1.434-6.081; P=0.003). Onset to treatment time was an independent predictor (P<0.05) for ENI at 7 days after thrombolysis. The NIHSS score and diastolic blood pressure on admission were associated with symptomatic intracerebral hemorrhagic transformation.

CONCLUSIONS

Non-AF was independently associated with ENI after intravenous thrombolysis in AIS patients, but non-AF was not associated with the occurrence of symptomatic intracerebral hemorrhage. Onset to treatment time was an independent predictor of ENI at 7 days after thrombolysis in AIS patients.

Immunotherapy for Parkinson's disease

With the increasing prevalence of Parkinson’s disease (PD), there is an immediate need to interdict disease signs and symptoms. In recent years this need was met through therapeutic approaches focused on regenerative stem cell replacement and alpha-synuclein clearance. However, neither have shown long-term clinical benefit. A novel therapeutic approach designed to affect disease is focused on transforming the brain’s immune microenvironment. As disordered innate and adaptive immune functions are primary components of neurodegenerative disease pathogenesis, this has emerged as a clear opportunity for therapeutic development. Interventions that immunologically restore the brain’s homeostatic environment can lead to neuroprotective outcomes. These have recently been demonstrated in both laboratory and early clinical investigations. To these ends, efforts to increase the numbers and function of regulatory T cells over dominant effector cells that exacerbate systemic inflammation and neurodegeneration have emerged as a primary research focus. These therapeutics show broad promise in affecting disease outcomes beyond PD, such as for Alzheimer’s disease, stroke and traumatic brain injuries, which share common neurodegenerative disease processes.

Automated label-free detection of injured neuron with deep learning by two-photon microscopy

Stroke is a significant cause of morbidity and long-term disability globally. Detection of injured neuron is a prerequisite for defining the degree of focal ischemic brain injury, which can be used to guide further therapy. Here, we demonstrate the capability of two-photon microscopy (TPM) to label-freely identify injured neurons on unstained thin section and fresh tissue of rat cerebral ischemia-reperfusion model, revealing definite diagnostic features compared with conventional staining images. Moreover, a deep learning model based on convolutional neural network is developed to automatically detect the location of injured neurons on TPM images. We then apply deep learning-assisted TPM to evaluate the ischemic regions based on tissue edema, two-photon excited fluorescence signal intensity, as well as neuronal injury, presenting a novel manner for identifying the infarct core, peri-infarct area, and remote area. These results propose an automated and label-free method that could provide supplementary information to augment the diagnostic accuracy, as well as hold the potential to be used as an intravital diagnostic tool for evaluating the effectiveness of drug interventions and predicting potential therapeutics.

Effects of Urinary Kallidinogenase on NIHSS score, mRS score, and fasting glucose levels in acute ischemic stroke patients with abnormal glucose metabolism: A prospective cohort study

Urinary kallidinogenase may assist recovery acute ischemic stroke. This study evaluated the effect of urinary kallidinogenase on National Institute of Health Stroke Scale (NIHSS) score, modified Rankin scale (mRS) score, and fasting glucose levels in patients with acute ischemic stroke (AIS) combined with diabetes mellitus and impaired fasting glucose.Patients with AIS and abnormal glucose metabolism were enrolled in this prospective cohort study and divided into 2 groups. The human urinary kallidinogenase (HUK) group were treated with urinary kallidinogenase and standard treatment; the control group received standard treatment. NIHSS scores, mRS scores, and fasting blood glucose were evaluated and compared.A total of 113 patients were included: 58 in the HUK group and 55 in the control group. NIHSS scores decreased with treatment in both groups (time effect P < .05), but were lower in the HUK group (main effect P = .026). The mRS score decreased in both groups from 10 until 90 days after treatment (time effect P < .05); the 2 groups were similar (main effect, P = .130). Blood glucose levels decreased in both groups 10 days after treatment (time effect, P < .05), but there was no significant treatment effect (main effect, P = .635). Multivariate analysis showed blood uric acid >420 μmol/L (odds ratio [OR]: 0.053, 95% confidence interval [CI]: 0.008-0.350; P = .002) and application of HUK (OR: 0.217, 95% CI: 0.049-0.954; P = .043) were associated with 90% NIHSS recovery. Baseline NIHSS score was independently associated with poor curative effect.Urinary kallidinogenase with conventional therapy significantly improved NIHSS scores in patients with AIS. Urinary kallidinogenase also showed a trend toward lower fasting blood glucose levels, although the level did not reach significance.

Early diagnosis of cerebral thrombosis by EGFP–EGF1 protein conjugated ferroferric oxide magnetic nanoparticles

Cerebral thrombosis disease is a worldwide problem, with high rates of morbidity, disability, and mortality. Magnetic resonance imaging diffusion-weighted imaging was used as an important early diagnostic method for cerebral thrombotic diseases; however, its diagnosis time is 2 h after onset. In this study, we designed EGFP–EGF1–NP–Fe3O4 for earlier diagnosis of cerebral thrombosis by taking advantage of EGFP–EGF1 fusion protein, in which EGF1 can bind with tissue factor and enhanced green fluorescent protein has previously been widely used as a fluorescent protein marker. EGFP–EGF1–NP–Fe3O4 or NP–Fe3O4 reaches the highest concentration in the infarction areas in 1 h. To evaluate the targeting ability of EGFP–EGF1–NP–Fe3O4, a fluorochrome dye, Dir, was loaded into the nanoparticle. As shown by the in vivo organ multispectral fluorescence imaging, Dir-loaded EGFP–EGF1–NP–Fe3O4 exhibited higher fluorescence than those of model rats treated with Dir-loaded NP–Fe3O4. Coronal frozen sections and transmission electron microscope further showed that EGFP–EGF1–NP–Fe3O4 was mainly accumulated in the tissue factor exposure region of brain. The data indicated that the EGFP–EGF1–NP–Fe3O4 targeted cerebral thrombosis and might be applied in the early diagnosis of intracranial thrombosis.

Association of PAI-1 4G/5G Polymorphism with Ischemic Stroke in Chinese Patients with Type 2 Diabetes Mellitus

BACKGROUND/AIM

To investigate the association of the genetic polymorphisms of the plasminogen activator inhibitor type 1 (PAI-1) gene with the risk of ischemic stroke (IS) in subjects with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

Using a case-control study design, 175 individuals with T2D and IS were enrolled in the case group and 125 patients with T2D without IS were enrolled as controls. The clinical characteristics of the groups were compared, and genotypes were determined by direct DNA sequencing.

RESULTS

Male and hypertensive subjects were higher in the IS group (p = 0.002 and 0.014, respectively). High-density lipoprotein (HDL) and apolipoprotein A1 (APOA1) were lower in the IS group (p = 0.011 and 0.025, respectively); hemoglobin A1c (HbA1c), total homocysteine (tHcy), and FT4 levels were higher in the IS group (p = 0.022, 0.003, and 0.008, respectively). The 4G/4G, 4G/5G, and 5G/5G genotype frequencies were 40.0%, 46.4%, and 13.6% in the control group versus 31.4%, 52.0% and 16.6% in the IS group, respectively. Hypertension (odds ratio [OR] = 1.953, p = 0.020), tHcy (OR = 1.059, p = 0.029), thyroid-stimulating hormone (OR = 0.876, p = 0.039), and the PAI-1 genotype dominant allele model (OR = 1.748, p = 0.047) were associated with IS by multivariate analysis.

CONCLUSION

The PAI-1 genotype dominant allele model was a risk factor for IS in patients with T2DM of Jinan, China.

Superfine Magnetic Resonance Imaging of the Cerebrovasculature Using Self-Assembled Branched Polyethylene Glycol-Gd Contrast Agent

Magnetic resonance angiography is an attractive method for the visualization of the cerebrovasculature, but small-sized vessels are hard to visualize with the current clinically approved agents. In this study, a polymeric contrast agent for the superfine imaging of the cerebrovasculature is presented. Eight-arm polyethylene glycol with a molecular weight of ≈17 000 Da conjugated with a Gd chelate and fluorescein (F-8-arm PEG-Gd) is used. The relaxivity rate is 9.3 × 10^-3 m^-1 s^-1 , which is threefold higher than that of free Gd chelate. Light scattering analysis reveals that F-8-arm PEG-Gd is formed by self-assembly. When the F-8-arm PEG-Gd is intravenously injected, cerebrovasculature as small as 100 µm in diameter is clearly visualized. However, signals are not enhanced when Gd chelate and Gd chelate-conjugated 8-arm PEG are injected. Furthermore, small vasculature around infarct region in rat stroke model can be visualized. These results suggest that F-8-arm PEG-Gd enhances the MR imaging of cerebrovasculature.

Radiological imaging in acute ischaemic stroke

Patients who suffer acute ischaemic stroke can be treated with thrombolysis if therapy is initiated early. Radiological evaluation of the intracranial tissue before such therapy can be given is mandatory. In this review current radiological diagnostic strategies are discussed for this patient group. Beyond non-enhanced computed tomography (CT), the standard imaging method for many years, more sophisticated CT stroke protocols including CT angiography and CT perfusion have been developed, and additionally an increasing number of patients are examined with magnetic resonance imaging as the first imaging method used. Advantages and challenges of the different methods are discussed.

Neuroprotective mechanism of HIF-1α overexpression in the early stage of acute cerebral infarction in rats

The present study aimed to explore the expression and neuroprotective mechanism of hypoxia inducible factor (HIF-1α) in the brain tissue of a rat model of early acute cerebral infarction. A total of 64 Sprague Dawley rats were randomly divided into surgery and sham groups and the model of focal cerebral infarction was established by the suture-occluded method. In the sham group, blood vessels were separated but not occluded. Rats in the surgery and sham groups were subdivided into eight groups (n=4/group). Blood samples was collected at 8 time points including 30 min and 1, 3, 6, 12, 48, 24 and 72 h, respectively, and HIF-1α content was detected using ELISA. Brain tissues of rats in all groups were harvested following blood collection. HIF-1α protein expression was detected by immunohistochemistry and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling was used to analyze the brain cell apoptosis index. ELISA results demonstrated that rats in the surgery group began to express HIF-1α within 30 min, and HIF-1α expression levels gradually increased, peaking at 12 h. HIF-1α expression levels were significantly increased in the surgery group at all time points, as compared with the sham group (P<0.05). The concentration of HIF-1α decreased rapidly in 12 h. At various time points, HIF-1α protein expression in the brain tissue of rats in the sham group was negative. HIF-1α protein expression was significantly increased in the surgery group (P<0.05), peaking at 12 h, and decreasing after this point. As compared with the sham group, the apoptosis indices of the brain tissue of rats in the surgery group exhibited a gradual increasing trend with significant decreases observed after 12 h (P<0.05). Intra-group comparison of all indices in the surgery group, indicated that there was a statistically significant difference between postoperative 12 h and other time points (P<0.05). In conclusion, the present study demonstrated that HIF-1α was highly expressed in the brain tissue of rat models of early acute cerebral infarction. The results also indicated that HIF-1α significantly reduced the apoptosis of infarcted cells, suggesting that HIF-1α may have a neuroprotective role in early acute cerebral infarction.

Recombinant human soluble thrombomodulin ameliorates cerebral ischemic injury through a high-mobility group box 1 inhibitory mechanism without hemorrhagic complications in mice

BACKGROUND

It has been reported that recombinant human soluble thrombomodulin (rhsTM) has a high-mobility group box (HMGB)1 inhibitory effect. Some investigators reported that HMGB1 is associated with ischemic stroke. However, there have been no previous studies to determine whether rhsTM can ameliorate cerebral ischemic injury through its HMGB1 inhibitory mechanism in ischemic stroke. We investigated the effects of rhsTM on cerebral ischemic injury in a 4-h middle cerebral artery occlusion (MCAO) murine model.

METHODS

rhsTM (1 or 5mg/kg, i.v.) was administered immediately after 4-h MCAO. Infarct volume, motor coordination, plasma HMGB1 level, and hemorrhage volume were evaluated 24h after 4-h MCAO.

RESULTS

The infarct volume (P<0.05) was reduced by rhsTM in mice subjected to 4-h MCAO in a dose-dependent manner. Moreover, rhsTM (5mg/kg) significantly improved motor coordination determined by the rotarod test (P<0.05), and significantly decreased plasma HMGB1 level compared with vehicle-treated controls (P<0.001). In addition, there was no difference in hemorrhage volume between vehicle-treated controls and the rhsTM treatment group.

CONCLUSIONS

This represents the first report that rhsTM ameliorates cerebral ischemic injury through an HMGB1 inhibitory mechanism without hemorrhagic complications in mice. Taken together, these observations indicate a palliative effect of rhsTM and suggest new therapeutic possibilities for treatment of ischemic stroke via inhibition of HMGB1.

Fast semi-automated lesion demarcation in stroke

Lesion–behaviour mapping analyses require the demarcation of the brain lesion on each (usually transverse) slice of the individual stroke patient's brain image. To date, this is generally thought to be most precise when done manually, which is, however, both time-consuming and potentially observer-dependent. Fully automated lesion demarcation methods have been developed to address these issues, but these are often not practicable in acute stroke research where for each patient only a single image modality is available and the available image modality differs over patients. In the current study, we evaluated a semi-automated lesion demarcation approach, the so-called Clusterize algorithm, in acute stroke patients scanned in a range of common image modalities. Our results suggest that, compared to the standard of manual lesion demarcation, the semi-automated Clusterize algorithm is capable of significantly speeding up lesion demarcation in the most commonly used image modalities, without loss of either lesion demarcation precision or lesion demarcation reproducibility. For the three investigated acute datasets (CT, DWI, T2FLAIR), containing a total of 44 patient images obtained in a regular clinical setting at patient admission, the reduction in processing time was on average 17.8 min per patient and this advantage increased with increasing lesion volume (up to 60 min per patient for the largest lesion volumes in our datasets). Additionally, our results suggest that performance of the Clusterize algorithm in a chronic dataset with 11 T1 images was comparable to its performance in the acute datasets. We thus advocate the use of the Clusterize algorithm, integrated into a simple, freely available SPM toolbox, for the precise, reliable and fast preparation of imaging data for lesion–behaviour mapping analyses.

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We evaluated a semi-automated lesion demarcation approach in stroke patients.

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We compared our approach to the gold standard of manual lesion demarcation.

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We investigated typically used image modalities in acute clinical settings.

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Precision and reliability of our approach were comparable to the gold standard.

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Our approach was significantly faster than the gold standard.