Prevention of stroke: a strategic global imperative

MicroRNA Analysis of Human Stroke Brain Tissue Resected during Decompressive Craniectomy/Stroke-Ectomy Surgery

BACKGROUND

Signaling pathways mediated by microRNAs (miRNAs) have been identified as one of the mechanisms that regulate stroke progression and recovery. Recent investigations using stroke patient blood and cerebrospinal fluid (CSF) demonstrated disease-specific alterations in miRNA expression. In this study, for the first time, we investigated miRNA expression signatures in freshly removed human stroke brain tissue.

METHODS

Human brain samples were obtained during craniectomy and brain tissue resection in severe stroke patients with life-threatening brain swelling. The tissue samples were subjected to histopathological and immunofluorescence microscopy evaluation, next generation miRNA sequencing (NGS), and bioinformatic analysis.

RESULTS

miRNA NGS analysis detected 34 miRNAs with significantly aberrant expression in stroke tissue, as compared to non-stroke samples. Of these miRNAs, 19 were previously identified in stroke patient blood and CSF, while dysregulation of 15 miRNAs was newly detected in this study. miRNA direct target gene analysis and bioinformatics approach demonstrated a strong association of the identified miRNAs with stroke-related biological processes and signaling pathways.

CONCLUSIONS

Dysregulated miRNAs detected in our study could be regarded as potential candidates for biomarkers and/or targets for therapeutic intervention. The results described herein further our understanding of the molecular basis of stroke and provide valuable information for the future functional studies in the experimental models of stroke.

CircDLGAP4 overexpression relieves oxygen-glucose deprivation-induced neuronal injury by elevating NEGR1 through sponging miR-503-3p

Circular RNAs (circRNAs) have been reported to play vital regulatory roles in human diseases. However, the functions of circRNAs in ischemic stroke (IS) are limited. In this study, we aimed to explore the functions and mechanisms of circRNA DLG associated protein 4 (circDLGAP4) in IS development. Oxygen-glucose deprivation (OGD)-treated HCN-2 cells were used to mimic IS environment in vitro. Quantitative real-time polymerase chain reaction (qRT-PCR) assay was used to detect the levels of circDLGAP4, microRNA-503-3p (miR-503-3p) and neuronal growth regulator 1 (NEGR1) mRNA. RNase R assay was conducted to analyze the stability of circDLGAP4. Cell Counting Kit-8 (CCK-8) assay and flow cytometry analysis were adopted for cell viability and death, respectively. Western blot assay was performed for protein levels. Enzyme-linked immunosorbent assay (ELISA) kits were used to examine the concentrations of inflammatory cytokines. Dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull-down assay were employed to analyze the relationships among circDLGAP4, miR-503-3p and NEGR1. CircDLGAP4 level was declined in HCN-2 cells after OGD treatment. CircDLGAP4 overexpression promoted cell viability and suppressed cell death and inflammatory cytokine concentrations in OGD-treated HCN-2 cells. CircDLGAP4 acted as the sponge for miR-503-3p and the impacts of circDLGAP4 overexpression on cell viability, death and inflammation in OGD-treated HCN-2 cells were reversed by miR-503-3p elevation. Furthermore, NEGR1 was the target gene of miR-503-3p. MiR-503-3p inhibition ameliorated OGD-induced HCN-2 cell impairments, but NEGR1 knockdown abolished the effects. CircDLGAP4 alleviated OGD-induced HCN-2 cell damage by regulating miR-503-3p/NEGR1 axis.

Fighting Against Stroke in Latin America: A Joint Effort of Medical Professional Societies and Governments

Introduction: Stroke is one of the leading causes of death in Latin America, a region with countless gaps to be addressed to decrease its burden. In 2018, at the first Latin American Stroke Ministerial Meeting, stroke physician and healthcare manager representatives from 13 countries signed the Declaration of Gramado with the priorities to improve the region, with the commitment to implement all evidence-based strategies for stroke care. The second meeting in March 2020 reviewed the achievements in 2 years and discussed new objectives. This paper will review the 2-year advances and future plans of the Latin American alliance for stroke. Method: In March 2020, a survey based on the Declaration of Gramado items was sent to the neurologists participants of the Stroke Ministerial Meetings. The results were confirmed with representatives of the Ministries of Health and leaders from the countries at the second Latin American Stroke Ministerial Meeting. Results: In 2 years, public stroke awareness initiatives increased from 25 to 75% of countries. All countries have started programs to encourage physical activity, and there has been an increase in the number of countries that implement, at least partially, strategies to identify and treat hypertension, diabetes, and lifestyle risk factors. Programs to identify and treat dyslipidemia and atrial fibrillation still remained poor. The number of stroke centers increased from 322 to 448, all of them providing intravenous thrombolysis, with an increase in countries with stroke units. All countries have mechanical thrombectomy, but mostly restricted to a few private hospitals. Pre-hospital organization remains limited. The utilization of telemedicine has increased but is restricted to a few hospitals and is not widely available throughout the country. Patients have late, if any, access to rehabilitation after hospital discharge. Conclusion: The initiative to collaborate, exchange experiences, and unite societies and governments to improve stroke care in Latin America has yielded good results. Important advances have been made in the region in terms of increasing the number of acute stroke care services, implementing reperfusion treatments and creating programs for the detection and treatment of risk factors. We hope that this approach can reduce inequalities in stroke care in Latin America and serves as a model for other under-resourced environments.

Stroke Risk Factors in United States: An Analysis of the 2013-2018 National Health and Nutrition Examination Survey

Purpose

This research intended to identify significant risk factors of stroke among the elderly population in the United States using the k-means clustering method.

Patients and Methods

In this cross-sectional study, we analyzed data of 4346 subjects aged ≥60 years using the National Health and Nutrition Examination Survey (NHANES) 2013-2018 datasets. Questionnaire data, dietary data, and laboratory data were accessed to acquire measurements of the potential risk factors. A pre-defined classification method was used based on the Medical Condition Questionnaire to define the stroke group. K-means clustering analysis used all potential risk factors for differentiating both groups. A stepwise logistic regression analysis examined the association between significant risk factors and the odds of stroke.

Results

Age (OR:1.053, 95% CI:1.029-1.077), diabetes (OR: 28.019, 95% CI: 19.139-41.020), glycohemoglobin (OR: 2.309, 95% CI: 1.818-2.934), plasma fasting glucose (OR: 1.017, 95% CI: 1.010-1.024), hypertension (OR: 2.343, 95% CI: 1.602-3.426), dietary fiber consumption (OR:0.980, 95% CI:0.964-0.995), and education level (OR:0.541, 95% CI: 0.411-0.713) were identified as significant risk factor for stroke among the elderly population in the k-means clustering method. In the pre-defined grouping method, age (OR:1.093, 95% CI:1.054-1.132), diabetes (OR:2.228, 95% CI: 1.432-3.466), hypertension (OR:2.295, 95% CI:1.338-3.938), and dietary fiber consumption (OR: 0.966, 95CI%:0.947-0.985) were found to influence to the risk of stroke.

Conclusion

Age, hypertension, dietary fiber consumption, and education level are the significant risk factors of stroke among elders aged >60 years. Among all the risk factors, diabetes is the strongest predictor of stroke. Glycohemoglobin and plasma fasting glucose are also associated with stroke risks, implying that glycemic control is particularly crucial in stroke prevention and management among older adults.

Coffee consumption and the risk of cerebrovascular disease: a meta-analysis of prospective cohort studies

Background

Stroke is a crucial health threat to adults worldwide. Despite extensive knowledge of risk-factor mitigation, no primary prevention exists for healthy people. Coffee is a widely consumed beverage globally. Health benefit of coffee for several neurological diseases has been identified; however, the association between stroke risk and coffee consumption in healthy people has not been determined. We investigated the effect of coffee on stroke risk by conducting a meta-analysis of prospective cohort studies.

Methods

Electronic databases, namely PubMed, BioMed Central, Medline, and Google Scholar, were searched using terms related to stroke and coffee. Articles that described clear diagnostic criteria for stroke and details on coffee consumption were included. The reference lists of relevant articles were reviewed to identify eligible studies not shortlisted using these terms. Enrolled studies were grouped into three outcome categories: overall stroke, hemorrhagic stroke, and ischemic stroke.

Results

Seven studies were included and all of them were large-scale, long-term, follow-up cohort studies of a healthy population. Upon comparing the least-coffee-consuming groups from each study, the meta-analysis revealed a reduction in the risk of overall stroke during follow-up (hazard ratio [HR] for overall stroke = 0.922, 95% confidence interval [CI] = 0.855–0.994, P = 0.035). In studies with a clear definition of hemorrhagic and ischemic stroke, coffee consumption reduced the risk of ischemic stroke more robustly than that of hemorrhagic stroke (hemorrhagic, HR = 0.895, 95% CI = 0.824–0.972, P = .008; ischemic, HR = 0.834, 95% CI = 0.739–0.876, P < .001). No obvious dose-dependent or U-shaped effect was observed.

Conclusions

Coffee consumption reduces the risk of overall stroke, especially ischemic stroke. Further investigation is required to identify beneficial components in coffee, including caffeine and phenolic acids, to develop preventive medication for stroke.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-021-02411-5.

Hypoxia conditioned mesenchymal stem cells in tissue regeneration application

Mesenchymal stem cells (MSCs) have been demonstrated as promising cell sources for tissue regeneration due to their capability of self-regeneration, differentiation and immunomodulation. MSCs also exert extensive paracrine effects through release of trophic factors and extracellular vesicles. However, despite extended exploration of MSCs in pre-clinical studies, the results are far from satisfactory due to the poor engraftment and low level of survival after implantation. Hypoxia preconditioning has been proposed as an engineering approach to improve the therapeutic potential of MSCs. During in vitro culture, hypoxic conditions can promote MSC proliferation, survival and migration through various cellular responses to the reduction of oxygen tension. The multilineage differentiation potential of MSCs is altered under hypoxia, with consistent reports of enhanced chondrogenesis. Hypoxia also stimulates the paracrine activities of MSCs and increases the production of secretome both in terms of soluble factors as well as extracellular vesicles. The secretome from hypoxia preconditioned MSCs play important roles in promoting cell proliferation and migration, enhancing angiogenesis while inhibiting apoptosis and inflammation. In this review, we summarise current knowledge of hypoxia-induced changes in MSCs and discuss the application of hypoxia preconditioned MSCs as well as hypoxic secretome in different kinds of disease models.

The Effectiveness of Stroke Riskometer™ in Improving Stroke Risk Awareness in Malaysia: A Study Protocol of a Cluster-Randomized Controlled Trial

BACKGROUND

Stroke is considered the second leading cause of mortality and disability worldwide. The increasing burden of stroke is strong evidence that currently used primary prevention strategies are not sufficiently effective. The Stroke Riskometer™ application (app) represents a new stroke prevention strategy distinctly different from the conventional high-cardiovascular disease risk approach.

OBJECTIVE

This proposed study aims to evaluate the effectiveness of the Stroke Riskometer™ app in improving stroke awareness and stroke risk probability amongst the adult population in Malaysia.

METHODS

A non-blinded, parallel-group cluster-randomized controlled trial with a 1:1 allocation ratio will be implemented in Kelantan, Malaysia. Two groups with a sample size of 66 in each group will be recruited. The intervention group will be equipped with the Stroke Riskometer™ app and informational leaflets, while the control group will be provided with standard management, including information leaflets only. The Stroke Riskometer™ app was developed according to the self-management model of chronic diseases based on self-regulation and social cognitive theories. Data collection will be conducted at baseline and on the third week, sixth week, and sixth month follow-up via telephone interview or online questionnaire survey. The primary outcome measure is stroke risk awareness, including the domains of knowledge, perception, and intention to change. The secondary outcome measure is stroke risk probability within 5 and 10 years adjusted to each participant's socio-demographic and/or socio-economic status. An intention-to-treat approach will be used to evaluate these measures. Pearson's χ2 or independent t test will be used to examine differences between the intervention and control groups. The generalized estimating equation and the linear mixed-effects model will be employed to test the overall effectiveness of the intervention.

CONCLUSION

This study will evaluate the effect of Stroke Riskometer™ app on stroke awareness and stroke probability and briefly evaluate participant engagement to a pre-specified trial protocol. The findings from this will inform physicians and public health professionals of the benefit of mobile technology intervention and encourage more active mobile phone-based disease prevention apps.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT04529681.

Mendelian Randomization Studies in Stroke: Exploration of Risk Factors and Drug Targets With Human Genetic Data

Elucidating the causes of stroke is key to developing effective preventive strategies. The Mendelian randomization approach leverages genetic variants related to an exposure of interest to investigate the effects of varying that exposure on disease risk. The random allocation of genetic variants at conception reduces confounding from environmental factors and thus strengthens causal inference, analogous to treatment allocation in a randomized controlled trial. With the recent explosion in the availability of human genetic data, Mendelian randomization has proven a valuable tool for studying risk factors for stroke. In this review, we provide an overview of recent developments in the application of Mendelian randomization to unravel the pathophysiology of stroke subtypes and identify therapeutic targets for clinical translation. The approach has offered novel insight into the differential effects of risk factors and antihypertensive, lipid-lowering, and anticoagulant drug classes on risk of stroke subtypes. Analyses have further facilitated the prioritization of novel drug targets, such as for inflammatory pathways underlying large artery atherosclerotic stroke and for the coagulation cascade that contributes to cardioembolic stroke. With continued methodological advances coupled with the rapidly increasing availability of genetic data related to a broad range of stroke phenotypes, the potential for Mendelian randomization in this context is expanding exponentially.

Daytime sleepiness and risk of stroke: A Mendelian randomization analysis

OBJECTIVE

Daytime sleepiness is known to be related to stroke, but whether daytime sleepiness is a risk factor for stroke remains unclear. We conducted a two-sample Mendelian randomization study to assess the relationship between daytime sleepiness and stroke, ischemic stroke (IS) and IS subtypes.

METHODS

Thirty-six single-nucleotide polymorphisms (SNPs) associated with daytime sleepiness were selected as instrumental variables, which were identified from a recent genome-wide association study(N = 452,071). Summary statistics of the SNPs on stroke, IS and IS subtypes were derived from the MEGASTROKE consortium with 40,585 stroke cases and 406,111 controls.

RESULTS

We found that daytime sleepiness was associated with large artery stroke (OR, 6.75; 95%CI, 1.49-30.57; p = 0.013), but not with all stroke (OR, 1.29; 95%CI, 0.81-2.05; p = 0.282), all ischemic stroke(OR, 1.46; 95%CI, 0.90-2.39; p = 0.136), cardioembolic stroke(OR, 1.0; 95%CI, 0.39-2.64; p = 0.984), or small artery stroke(OR, 1.52; 95%CI, 0.46-5.05; p = 0.485).

CONCLUSION

Our findings indicated that daytime sleepiness is causally associated with an increased risk of large artery stroke. Further studies are necessary to verify our results and explain the physiological mechanisms.

Habitual flavonoid intake and ischemic stroke incidence in the Danish Diet, Cancer, and Health Cohort

BACKGROUND

Flavonoid-rich foods have antiinflammatory, antiatherogenic, and antithrombotic properties that may contribute to a lower risk of ischemic stroke.

OBJECTIVES

We aimed to investigate the relationship between habitual flavonoid consumption and incidence of ischemic stroke in participants from the Danish Diet, Cancer and Health Study.

DESIGN

In this prospective cohort study, 55,169 Danish residents without a prior ischemic stroke [median (IQR) age at enrolment of 56 y (52-60)], were followed for 21 y (20-22). We used Phenol-Explorer to estimate flavonoid intake from food frequency questionnaires obtained at study entry. Incident cases of ischemic stroke were identified from Danish nationwide registries and restricted cubic splines in Cox proportional hazards models were used to investigate relationships with flavonoid intake.

RESULTS

During follow-up, 4237 individuals experienced an ischemic stroke. Compared with participants in Q1 and after multivariable adjustment for demographics and lifestyle factors, those in Q5-for intake of total flavonoids, flavonols, and flavanol oligo + polymers-had a 12% [HR (95% CI): 0.88 (0.81, 0.96)], 10% [0.90 (0.82, 0.98)], and 18% [0.82 (0.75, 0.89)] lower risk of ischemic stroke incidence, respectively. Multivariable (demographic and lifestyle) adjusted associations for anthocyanins and flavones with risk of ischemic stroke were not linear, with moderate but not higher intakes associated with lower risk [anthocyanins Q3 vs. Q1 HR (95% CI): 0.85 (0.79, 0.93); flavones: 0.90 (0.84, 0.97)]. Following additional adjustment for dietary confounders, similar point estimates were observed; however, significance was only retained for anthocyanins and flavanol oligo + polymers [anthocyanins Q3 vs. Q1 HR (95% CI): 0.86 (0.79, 0.94); flavanol oligo + polymers Q5 vs. Q1 0.86 (0.78, 0.94)].

CONCLUSIONS

These findings suggest that moderate habitual consumption of healthy flavonoid-rich foods is associated with a lower risk of ischemic stroke and further investigation is therefore warranted.

Scalable Bio Marker Combinations for Early Stroke Diagnosis: A Systematic Review

Background: Acute stroke treatment is a time-critical process in which every minute counts. Laboratory biomarkers are needed to aid clinical decisions in the diagnosis. Although imaging is critical for this process, these biomarkers may provide additional information to distinguish actual stroke from its mimics and monitor patient condition and the effect of potential neuroprotective strategies. For such biomarkers to be effectively scalable to public health in any economic setting, these must be cost-effective and non-invasive. We hypothesized that blood-based combinations (panels) of proteins might be the key to this approach and explored this possibility through a systematic review. Methods: We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines for systematic review. Initially, the broader search for biomarkers for early stroke diagnosis yielded 704 hits, and five were added manually. We then narrowed the search to combinations (panels) of the protein markers obtained from the blood. Results: Twelve articles dealing with blood-based panels of protein biomarkers for stroke were included in the systematic review. We observed that NR2 peptide (antibody against the NR2 fragment) and glial fibrillary acidic protein (GFAP) are brain-specific markers related to stroke. Von Willebrand factor (vWF), matrix metalloproteinase 9 (MMP-9), and S100β have been widely used as biomarkers, whereas others such as the ischemia-modified albumin (IMA) index, antithrombin III (AT-III), and fibrinogen have not been evaluated in combination. We herein propose the following new combination of biomarkers for future validation: panel 1 (NR2 + GFAP + MMP-9 + vWF + S100β), panel 2 (NR2 + GFAP + MMP-9 + vWF + IMA index), and panel 3 (NR2 + GFAP + AT-III + fibrinogen). Conclusions: More research is needed to validate, identify, and introduce these panels of biomarkers into medical practice for stroke recurrence and diagnosis in a scalable manner. The evidence indicates that the most promising approach is to combine different blood-based proteins to provide diagnostic precision for health interventions. Through our systematic review, we suggest three novel biomarker panels based on the results in the literature and an interpretation based on stroke pathophysiology.

STO: Stroke Ontology for Accelerating Translational Stroke Research

Introduction

Ontology-based annotation of evidence, using disease-specific ontologies, can accelerate analysis and interpretation of the knowledge domain of diseases. Although many domain-specific disease ontologies have been developed so far, in the area of cardiovascular diseases, there is a lack of ontological representation of the disease knowledge domain of stroke.

Methods

The stroke ontology (STO) was created on the basis of the ontology development life cycle and was built using Protégé ontology editor in the ontology web language format. The ontology was evaluated in terms of structural and functional features, expert evaluation, and competency questions.

Results

The stroke ontology covers a broad range of major biomedical and risk factor concepts. The majority of concepts are enriched by synonyms, definitions, and references. The ontology attempts to incorporate different users’ views on the stroke domain such as neuroscientists, molecular biologists, and clinicians. Evaluation of the ontology based on natural language processing showed a high precision (0.94), recall (0.80), and F-score (0.78) values, indicating that STO has an acceptable coverage of the stroke knowledge domain. Performance evaluation using competency questions designed by a clinician showed that the ontology can be used to answer expert questions in light of published evidence.

Conclusions

The stroke ontology is the first, multiple-view ontology in the domain of brain stroke that can be used as a tool for representation, formalization, and standardization of the heterogeneous data related to the stroke domain. Since this is a draft version of the ontology, the contribution of the stroke scientific community can help to improve the usability of the current version.

Reduced Retinal Microvascular Perfusion in Patients With Stroke Detected by Optical Coherence Tomography Angiography

Currently there is a shortage of biomarkers for stroke, one of the leading causes of death and disability in aging populations. Retinal vessels offer a unique and accessible “window” to study the microvasculature in vivo. However, the relationship between the retinal microvasculature and stroke is not entirely clear. To investigate the retinal microvascular characteristics in stroke, we recruited patients with stroke and age-matched control subjects from a tertiary hospital in China. The macular vessel density (VD) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP), foveal avascular zone (FAZ) metrics, and optical coherence tomography angiography (OCTA) measured optic disc VD were recorded for analysis. A total of 189 patients with stroke and 195 control subjects were included. After adjusting for sex, visual acuity, systolic and diastolic blood pressure, a history of smoking, levels of hemoglobulin (HbA1c), cholesterol, and high-density lipoprotein (HDL), the macular VD of SCP and DCP in all sectors was decreased in patients with stroke. In the stroke group, the VD around the FAZ and the VD of the optic disk were lower. Logistic regression found the parafovea-superior-hemi VD of DCP > 54.53% [odds ratio (OR): 0.169] as a protective factor of stroke. Using the integration of all OCTA parameters and traditional risk factors, the area under the receiver operating characteristic (AUC) curve of distinguishing patients with stroke was 0.962, with a sensitivity of 0.944 and a specificity of 0.871. Our study demonstrates that the retinal VD is decreased in patients with stroke independently of the traditional risk factors of stroke, which may shed light on the monitoring of stroke using the retinal microvascular parameters.

Public Stroke Knowledge, Awareness, and Response to Acute Stroke in Isfahan Iran: What is Less or Misinterpreted in Developing Countries

BACKGROUND

Considering the high burden of stroke in developing countries, it is important for the community to have adequate information and awareness of this disease. In this study, the baseline knowledge of an Iranian population towards stroke has been evaluated.

METHOD

This study was conducted in a governmental hospital in Isfahan, Iran. The participants were selected from the companions of non-cardio-vascular hospitalized patients. A self-administered questionnaire was designed for gathering information RESULTS: A total of 630 questionnaires were analysed. Hypertension and stress were the most frequently identified risk factors (recognised by 83.7% and 75.8% respectively), while pregnancy, oral contraceptives, and anti-coagulants were the least (recognised by 3.5%, 14.2% and 15.8% respectively). Knowledge of other important risk factors such as cardiac diseases was also relatively low (39.4%). Sudden visual difficulties and irrelevant speech were the least identified warning signs of stroke (45.3% and 34.6% respectively), however, knowledge towards all other warning signs was moderately good (each identified by 60-70%). Importantly only 44.2% of respondents were aware that stroke treatment should be started within the first 3 hours. Participants tended to have moderately good insight of most stroke complications and rehabilitation (60-70%). Urban residence, high level of education and knowing someone with a history of stroke were significant predictors of a higher level of stroke awareness.

CONCLUSION

The findings of this study indicate that there is a need to improve general knowledge of cardiac and hypercoagulable related risk factors. Furthermore, understanding of the importance of time critical stroke management and the ineffectiveness of traditional medicine needs to be raised in the general community.

Bayesian Analysis of Population Health Data

The analysis of population-wide datasets can provide insight on the health status of large populations so that public health officials can make data-driven decisions. The analysis of such datasets often requires highly parameterized models with different types of fixed and random effects to account for risk factors, spatial and temporal variations, multilevel effects and other sources on uncertainty. To illustrate the potential of Bayesian hierarchical models, a dataset of about 500,000 inhabitants released by the Polish National Health Fund containing information about ischemic stroke incidence for a 2-year period is analyzed using different types of models. Spatial logistic regression and survival models are considered for analyzing the individual probabilities of stroke and the times to the occurrence of an ischemic stroke event. Demographic and socioeconomic variables as well as drug prescription information are available at an individual level. Spatial variation is considered by means of region-level random effects.

Activin A improves the neurological outcome after ischemic stroke in mice by promoting oligodendroglial ACVR1B-mediated white matter remyelination

Activin A plays important roles in ischemic injury and white matter remyelination, but its mechanisms are unclear. In this study, the adult male C57BL/6 J mice were used to establish the model of 1 h middle cerebral artery occlusion/reperfusion (MCAO/R) 1 d to 28 d-induced ischemic stroke in vivo. We found that the neurological outcome was positively correlated with the levels of myelin associated proteins (include MAG, CNPase, MOG and MBP, n = 6 per group) both in corpus callosum and internal capsule of mice with ischemic stroke. The dynamic changes of Luxol fast blue (LFB) staining intensity, oligodendrocyte (CC1+) and proliferated oligodendrocyte precursor (Ki67+/PDGFRα+) cell numbers indicated demyelination and spontaneous remyelination occurred in the corpus callosum of mice after 1 h MCAO/R 1 d-28 d (n = 6 per group). Activin receptor type I (ACVR1) inhibitor SB431542 aggregated neurological deficits, and reduced MAG, MOG and MBP protein levels of mice with ischemic stroke (n = 6 per group). Meanwhile, recombinant mouse (rm) Activin A enhanced the neurological function recovery, MAG, MOG and MBP protein levels of mice with 1 h MCAO/R 28 d. In addition, the injection of AAV-based ACVR1B shRNA with Olig2 promoter could reverse rmActivin A-induced the increases of CC1+ cell number, LFB intensity, MAG, MOG and MBP protein levels in the corpus callosum (n = 6 per group), and neurological function recovery (n = 10 per group) of mice with 1 h MCAO/R 28 d. These results suggested that Activin A improves the neurological outcome through promoting oligodendroglial ACVR1B-mediated white matter remyelination of mice with ischemic stroke, which may provide a potential therapeutic strategy for ischemic stroke.

Can quantifying morphology and TMEM119 expression distinguish between microglia and infiltrating macrophages after ischemic stroke and reperfusion in male and female mice?

Background

Ischemic stroke is an acquired brain injury with gender-dependent outcomes. A persistent obstacle in understanding the sex-specific neuroinflammatory contributions to ischemic brain injury is distinguishing between resident microglia and infiltrating macrophages—both phagocytes—and determining cell population-specific contributions to injury evolution and recovery processes. Our purpose was to identify microglial and macrophage populations regulated by ischemic stroke using morphology analysis and the presence of microglia transmembrane protein 119 (TMEM119). Second, we examined sex and menopause differences in microglia/macrophage cell populations after an ischemic stroke.

Methods

Male and female, premenopausal and postmenopausal, mice underwent either 60 min of middle cerebral artery occlusion and 24 h of reperfusion or sham surgery. The accelerated ovarian failure model was used to model postmenopause. Brain tissue was collected to quantify the infarct area and for immunohistochemistry and western blot methods. Ionized calcium-binding adapter molecule, TMEM119, and confocal microscopy were used to analyze the microglia morphology and TMEM119 area in the ipsilateral brain regions. Western blot was used to quantify protein quantity.

Results

Post-stroke injury is increased in male and postmenopause female mice vs. premenopause female mice (p < 0.05) with differences primarily occurring in the caudal sections. After stroke, the microglia underwent a region, but not sex group, dependent transformation into less ramified cells (p < 0.0001). However, the number of phagocytic microglia was increased in distal ipsilateral regions of postmenopausal mice vs. the other sex groups (p < 0.05). The number of TMEM119-positive cells was decreased in proximity to the infarct (p < 0.0001) but without a sex group effect. Two key findings prevented distinguishing microglia from systemic macrophages. First, morphological data were not congruent with TMEM119 immunofluorescence data. Cells with severely decreased TMEM119 immunofluorescence were ramified, a distinguishing microglia characteristic. Second, whereas the TMEM119 immunofluorescence area decreased in proximity to the infarcted area, the TMEM119 protein quantity was unchanged in the ipsilateral hemisphere regions using western blot methods.

Conclusions

Our findings suggest that TMEM119 is not a stable microglia marker in male and female mice in the context of ischemic stroke. Until TMEM119 function in the brain is elucidated, its use to distinguish between cell populations following brain injury with cell infiltration is cautioned.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-021-02105-2.

Knowledge of Risk Factors and Warning Signs of Stroke Among Patients with Heart Disease at Tikur Anbessa Specialized Hospital

BACKGROUND

Stroke is a leading cause of mortality and disability worldwide and the economic costs of treatment and post-stroke care are extensive. The inability to identify stroke warning signs accurately is an important cause of delay in seeking medical attention, leading to potential ineligibility for acute intervention and which leads to secondary complications.

PURPOSE

To identify cardiac patients' knowledge of stroke risk factors and warning signs.

PATIENTS AND METHODS

The institutional based cross-sectional study design was employed. Participants were selected using systematic random sampling. Close-ended questionnaires were pre-tested and validated for consistency before data collection. Then after data collection, data were checked and entered into Epi-data 4.6. Finally, the cleaned data were exported to SPSS version 25 for analysis. Statistical analysis using binary logistic regression was done and Predictors with a p-value of <0.05 were considered statistically significant.

RESULTS

A total of 227 patients were included in the study, of which 140 (61.7%) of them identified physical inactivity, followed by hypertension126 (55.5%) as stroke risk factor while 15.4% of them did not know any risk factor of stroke. Amongst the study participants, 45.81% of them had adequate knowledge of stroke risk factors. Regarding stroke warning signs the most identified sign was sudden unilateral weakness 142 (62.6%) while 46 (20.26%) of them did not know at least one warning sign of a stroke. Based on multivariable logistic regression analysis, higher education level AOR 3.05 (95% CI 1.62-5.74) and Urban residence area AOR 2.07 (95% CI 1.05-4.1) were significantly associated with knowledge of stroke risk factors with p-value<0.05.

CONCLUSION

Study participants had inadequate knowledge of stroke risk factors and warning signs. Educational status and information about stroke are significantly associated with adequate knowledge of stroke risk factors, raising stroke awareness is the mainstay to reduce stroke burden.

Impact of Teleconsultation on Patients With Type 2 Diabetes in the Brazilian Public Health System: Protocol for a Randomized Controlled Trial (TELEconsulta Diabetes Trial)

BACKGROUND

Although the Brazilian Unified Health System (SUS) offers universal health coverage, access to quality care is often limited by social inequality and location. Although telemedicine has been shown to be an important tool in the efforts to overcome this problem, because it can provide access to specialist care and break the geographical barriers to health care, there are no national studies demonstrating its use in public health.

OBJECTIVE

This study aims to test the hypothesis that remote consultation can be as effective as standard face-to-face consultation for type 2 diabetes mellitus in the Brazilian public health system and to assess the associated costs related to teleconsultation in public health scenarios, for patients referred from Primary Health Care units of the SUS for specialist care.

METHODS

This is a pragmatic, phase 2, unicentric, open-label, noninferiority, blinded allocation, data-blinded, centrally randomized clinical trial. The inclusion criteria will be adults, both sexes, ≥18 years old, glycated hemoglobin (HbA1c) ≥8%. Outcomes will be evaluated by assessing symptoms, laboratory exams, anthropometric measurements, blood pressure, adverse events, and satisfaction level for 6 months. The costs of the teleconsultation will be assessed using the time-driven activity-based costing (TDABC) method to compare the costs with the face-to-face consultations. The noninferiority margin was set at 0.5%. Assuming an SD of 1.3% for both groups, true difference between the means of zero, and a type I error level of 5% (one-sided), it was estimated that 117 individuals per group would be necessary to achieve 90% power. Statistical analysis of the efficacy will be done using intention-to-treat and per-protocol approaches.

RESULTS

The results from this trial will be reported according to the CONSORT guidelines. The trial was approved by the institutional review board on October 5, 2019. Data collection started in January 2019 and is expected to finish in 2022. At the time of manuscript submission, 18 participants were recruited.

CONCLUSIONS

Our expectations are that providing remote access to health care will result in improvements in the health and quality of life of patients with type 2 diabetes and reduce costs and that both patients and clinicians will benefit from and be satisfied with this technology.

TRIAL REGISTRATION

Registro Brasileiro de Ensaios Clínicos RBR-8gpgyd; https://ensaiosclinicos.gov.br/rg/RBR-8gpgyd.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/23679.

Geranylgeranylacetone ameliorated ischemia/reperfusion induced-blood brain barrier breakdown through HSP70-dependent anti-apoptosis effect

BACKGROUND

Geranylgeranylacetone (GGA) has been recently reported to be centrally active after oral administration and protect against ischemic brain injury. This study was aimed to investigate the underlying mechanism of the protective effect of GGA.

METHODS

In this study, transient middle cerebral artery occlusion (tMCAO) was established. Neurological score and brain water content were adopted to investigate the role of GGA in vivo. Evans-blue (EB), western blot and immunofluorescence staining of tight junction proteins were performed to evaluate blood brain barrier (BBB) permeability. Inflammation response was assessed by immunofluorescence staining of MPO and Iba-1 and quantitative real-time polymerase chain reaction (qRT-PCR) of proinflammatory cytokines. In in vitro experiment, after oxygen-glucose deprivation (OGD), transepithelial electrical resistance (TEER) and endothelial cell monolayer permeability assay were conducted to examine the effects of GGA on barrier integrity. Furthermore, heat shock protein (HSP) 70 expression was knockdown by RNA interference in bEnd.3 cells to verify the involvement of HSP70 in the action of GGA. TEER, endothelial cell monolayer permeability, CCK8 and flow cytometry were performed. Expression of caspase-3 was detected by western blot and immunofluorescence staining.

RESULTS

Our results indicated that pretreatment with a single oral GGA dose (800 mg/kg) reduced the infarct volume and prevented the neurological impairments after tMCAO. Importantly, GGA ameliorated cerebral ischemia/reperfusion (I/R) induced BBB breakdown and rescued tight junction proteins (TJPs). GGA also profoundly decreased neutrophil infiltration, inhibited glial activation and reduced the expression of proinflammatory cytokines. Consistently, GGA significantly decreased OGD-induced BBB hyper-permeability in vitro. Consistent with the previous studies, GGA promoted HSP70 induction after I/R insult. Mechanistic study showed that GGA inhibited OGD-induced apoptosis of bEnd.3 cells. Genetic inhibition of HSP70 attenuated GGA's anti-apoptotic effect and reversed the protective effects of GGA.

Incidence, risk factors, prognosis, and health-related quality of life after stroke in a low-resource community in Chile (ÑANDU): a prospective population-based study

BACKGROUND

Stroke is a leading cause of disability and death worldwide. The best estimates of local, national, and global burden of stroke are derived from prospective population-based studies. We aimed to investigate the incidence, risk factors, long-term prognosis, care, and quality of life after stroke in the Ñuble region of Chile.

METHODS

We did a prospective community-based study with use of multiple overlapping sources of hospitalised, ambulatory, and deceased cases. Standardised diagnostic criteria were used to identify and follow up all cases occurring in the resident population of the Ñuble region, Chile (in a low-income rural-urban population including predominantly people of Indigenous-European heritage), for 1 year. Participants were included if they had a clinical diagnosis of stroke confirmed according to the study criteria. All cases were adjudicated by vascular neurologists. Incidence rates of first-ever stroke were calculated from the population of Ñuble according to the 2017 national census.

FINDINGS

From April 1, 2015, to March 31, 2016, we ascertained 1103 stroke cases, of which 890 (80·7%) were first-ever incident cases. The mean age of patients with first-ever stroke was 70·3 years (SD 14·1) and 443 (49·8%) were women. A CT scan was obtained in 801 (90%) of 890 patients (mean time from symptom onset to scan of 13·4 h (SD 29·8). The incidence of first-ever stroke age-adjusted to the world population was 121·7 (95% CI 113·7-130·1) per 100 000. The age-adjusted incidence rates, per 100 000 inhabitants, by main pathological subtypes were as follows: ischaemic stroke (101·5 [95% CI 90·9-113·0]); intracerebral haemorrhage (17·9 [13·5-23·4]), and subarachnoid haemorrhage (4·2 [2·1-7·3]). The 30-day case-fatality rate was 24·6% (21·9-27·6). At 6 months after the stroke, 55·9% (432 of 773) of cases had died or were disabled, which increased to 61·0% (456 of 747) at 12 months. Health-related quality of life in survivors was low at 6 months, improving slightly at 12 months after the stroke.

INTERPRETATION

The incidence of stroke in this low-resource population was higher than our previous finding in northern Chile and within the mid-range of most population-based stroke studies. This result was due mainly to a higher incidence of ischaemic stroke, probably associated with increasing age and a high prevalence of cardiometabolic risk factors in the population studied. Our findings suggest that more should be done for the prevention and care of stroke in communities like the Ñuble population.

FUNDING

The National Agency for Research and Development and the Technology-Health Research Fund, Clínica Alemana de Santiago, Boehringer Ingelheim, Bristol Meyers Squibb, The Herminda Martin Clinical Hospital of Chillán, Universidad Mayor, and Universidad de Concepción.

Trends and Challenges of Wearable Multimodal Technologies for Stroke Risk Prediction

We review in this paper the wearable-based technologies intended for real-time monitoring of stroke-related physiological parameters. These measurements are undertaken to prevent death and disability due to stroke. We compare the various characteristics, such as weight, accessibility, frequency of use, data continuity, and response time of these wearables. It was found that the most user-friendly wearables can have limitations in reporting high-precision prediction outcomes. Therefore, we report also the trend of integrating these wearables into the internet of things (IoT) and combining electronic health records (EHRs) and machine learning (ML) algorithms to establish a stroke risk prediction system. Due to different characteristics, such as accessibility, time, and spatial resolution of various wearable-based technologies, strategies of applying different types of wearables to maximize the efficacy of stroke risk prediction are also reported. In addition, based on the various applications of multimodal electroencephalography-functional near-infrared spectroscopy (EEG-fNIRS) on stroke patients, the perspective of using this technique to improve the prediction performance is elaborated. Expected prediction has to be dynamically delivered with high-precision outcomes. There is a need for stroke risk stratification and management to reduce the resulting social and economic burden.

Updating NO•/HNO interconversion under physiological conditions: A biological implication overview

Azanone (HNO/NO^-), also called nitroxyl, is a highly reactive compound whose biological role is still a matter of debate. A key issue that remains to be clarified regarding HNO and its biological activity is that of its endogenous formation. Given the overlap of the molecular targets and reactivity of nitric oxide (NO•) and HNO, its chemical biology was perceived to be similar to that of NO• as a biological signaling agent. However, despite their closely related reactivity, NO• and HNO's biochemical pathways are quite different. Moreover, the reduction of nitric oxide to azanone is possible but necessarily coupled to other reactions, which drive the reaction forward, overcoming the unfavorable thermodynamic barrier. The mechanism of this NO•/HNO interplay and its downstream effects in different contexts were studied recently, showing that more than fifteen moderate reducing agents react with NO• producing HNO. Particularly, it is known that the reaction between nitric oxide and hydrogen sulfide (H₂S) produces HNO. However, this rate constant was not reported yet. In this work, firstly the NO•/H₂S effective rate constant was measured as a function of the pH. Then, the implications of these chemical (non-enzymatic), biologically compatible, routes to endogenous HNO formation was discussed. There is no doubt that HNO could be (is?) a new endogenously produced messenger that mediates specific physiological responses, many of which were attributed yet to direct NO• effects.

Variations in knowledge, awareness and treatment of hypertension and stroke risk by country income level

OBJECTIVE

Hypertension is the most important modifiable risk factor for stroke globally. We hypothesised that country-income level variations in knowledge, detection and treatment of hypertension may contribute to variations in the association of blood pressure with stroke.

METHODS

We undertook a standardised case-control study in 32 countries (INTERSTROKE). Cases were patients with acute first stroke (n=13 462) who were matched by age, sex and site to controls (n=13 483). We evaluated the associations of knowledge, awareness and treatment of hypertension with risk of stroke and its subtypes and whether this varied by gross national income (GNI) of country. We estimated OR and population attributable risk (PAR) associated with treated and untreated hypertension.

RESULTS

Hypertension was associated with a graded increase in OR by reducing GNI, ranging from OR 1.92 (99% CI 1.48 to 2.49) to OR 3.27 (2.72 to 3.93) for highest to lowest country-level GNI (p-heterogeneity<0.0001). Untreated hypertension was associated with a higher OR for stroke (OR 5.25; 4.53 to 6.10) than treated hypertension (OR 2.60; 2.32 to 2.91) and younger age of first stroke (61.4 vs 65.4 years; p<0.01). Untreated hypertension was associated with a greater risk of intracerebral haemorrhage (OR 6.95; 5.61 to 8.60) than ischaemic stroke (OR 4.76; 3.99 to 5.68). The PAR associated with untreated hypertension was higher in lower-income regions, PAR 36.3%, 26.3%, 19.8% to 10.4% by increasing GNI of countries. Lifetime non-measurement of blood pressure was associated with stroke (OR 1.80; 1.32 to 2.46).

CONCLUSIONS

Deficits in knowledge, detection and treatment of hypertension contribute to higher risk of stroke, younger age of onset and larger proportion of intracerebral haemorrhage in lower-income countries.

Visualizing Peroxynitrite in Microvessels of the Brain with Stroke Using an Engineered Highly Specific Fluorescent Probe

Stroke is one of the leading causes of death and disability in the world, which is associated with malfunction of reactive oxygen species and reactive nitrogen species (ROS/RNS) in cerebral microvessels. In vivo monitoring these species, such as ONOO^-, with high selectivity in stroke process is of great significance for early diagnoses and therapies of the disease. Herein, by engineering an indoline-2,3-dione moiety as the recognizing domain, we proposed a novel fluorescence probe Rd-PN2 with highly specific response toward ONOO^-, even in the coexistence of other ROS/RNS with high concentration. Rd-PN2 showed high sensitivity and reaction speed in response to ONOO^- and exhibited satisfying performances in tracking the endogenously generated ONOO^- in living cells and zebrafish. Accordingly, Rd-PN2 can furnish real-time and in vivo visualizing of ONOO^- in cerebral microvessels of mice with ischemic and hemorrhagic strokes under two-photon microscopy. This work presented a precisely modulated fluorescence probe for real-time visualizing of ONOO^- production in cerebral micovessels, which will also help to acquire more accurate information in the studies of ONOO^- functions in the future.

Sex differences in quality of life after stroke were explained by patient factors, not clinical care: evidence from the Australian Stroke Clinical Registry

BACKGROUND AND PURPOSE

Women may receive stroke care less often than men. We examined the contribution of clinical care on sex differences and health-related quality of life (HRQoL) after stroke.

METHODS

We included first-ever strokes registered in the Australian Stroke Clinical Registry (2010-2014) with HRQoL assessed between 90 and 180 days after onset (EQ-5D-3L instrument) that were linked to hospital administrative data (up to 2013). Study factors included sociodemographics, comorbidities, walking ability on admission (stroke severity proxy) and clinical care (e.g. stroke unit care). Responses to the EQ-5D-3L were transformed into a total utility value (-0.516 'worse than death' to 1 'best' health). Quantile regression models, adjusted for confounding factors, were used to determine median differences (MD) in utility scores by sex.

RESULTS

Approximately 60% (6852/11 418) of stroke survivors had an EQ-5D-3L assessment (median 139 days; 44% female). Compared with men, women were older (median age 77.1 years vs. men 71.2 years) and fewer could walk on admission (37.9% vs. men 46.1%, P < 0.001). Women had lower utility values than men, and the difference was explained by age and stroke severity, but not clinical care [MD_{adjusted =} -0.039, 95% confidence interval: -0.056, -0.021]. Poorer HRQoL was observed in younger men (aged <65 years), particularly those with more comorbidities, and in older women (aged ≥75 years).

CONCLUSIONS

Stroke severity and comorbidities contribute to the poorer HRQoL in young men and older women. Further studies are needed to understand age-sex interaction to better inform treatments for different subgroups and ensure evidence-based treatments to reduce the severity of stroke are prioritized.

Complementary and alternative medicine use among ischemic stroke survivors in Jeddah, Saudi Arabia

OBJECTIVE

To determine the prevalence and pattern of complementary and alternative medicine (CAM) use and the CAM types used by stroke patients in Jeddah, Kingdom of Saudi Arabia.

METHODS

This cross-sectional study included 152 ischemic stroke survivors who visited King Fahad Hospital, Jeddah, Kingdom of Saudi Arabia, between January 2018 and December 2019. Phone-based and face-to-face surveys were conducted. Data on the patients` demographic characteristics, their use of CAM, and their pattern of CAM use were gathered.

RESULTS

Ninety (59.2%) stroke patients used CAM, mainly cauterization (29.61%) and Quran recitation by a religious sheik (28.95%). Most of the patients (72.22%) used CAM post-hospitalization and within less than one month from stroke onset (62.22%). A minority (6.67%) of the patients stopped their medication while on CAM. Some patients (25.56% to 31.11%) discussed with their physician their use of CAM. The CAM users reported a subjective improvement in their physical weakness (45.6%) and psychological wellbeing (62.2%). The patients learned about CAM mainly from their relatives and friends (96.7%), and the most common reason for their CAM use was their belief in this intervention (42.22%).

CONCLUSION

The CAM use was prevalent among our cohort of Saudi ischemic stroke patients, and cauterization and Quran recitation were the most commonly used CAM interventions. An effective communication was lacking between the medical professionals and the stroke patients as regards CAM use despite the interest of the patients in this intervention.

Cardiovascular Health and Stroke in Older British Men: Prospective Findings From the British Regional Heart Study

BACKGROUND AND PURPOSE

Research exploring the utility of cardiovascular health (CVH) and its Life's Simple 7 (LS7) components (body mass index, blood pressure [BP], glucose, cholesterol, physical activity, smoking, and diet) for prevention of stroke in older adults is limited. In the British Regional Heart Study, we explored (1) prospective associations of LS7 metrics and composite CVH scores with, and their impact on, stroke in middle and older age; and (2) if change in CVH was associated with subsequent stroke.

METHODS

Men without cardiovascular disease were followed from baseline recruitment (1978-1980), and again from re-examination 20 years later, for stroke over a median period of 20 years and 16 years, respectively. LS7 were measured at each time point except baseline diet. Cox models estimated hazard ratios (95% CI) of stroke for (1) ideal and intermediate versus poor levels of LS7; (2) composite CVH scores; and (3) 4 CVH trajectory groups (low-low, low-high, high-low, high-high) derived by dichotomising CVH scores from each time point across the median value. Population attributable fractions measured impact of LS7.

RESULTS

At baseline (n=7274, mean age 50 years), healthier levels of BP, physical activity, and smoking were associated with reduced stroke risk. At 20-year follow-up (n=3798, mean age 69 years) only BP displayed an association. Hazard ratios for intermediate and ideal (versus poor) levels of BP 0.65 (0.52-0.81) and 0.40 (0.24-0.65) at baseline; and 0.84 (0.67-1.05) and 0.57 (0.36-0.90) at 20-year follow-up. With reference to low-low trajectory, the low-high trajectory was associated with 40% reduced risk, hazard ratio 0.60 (0.44-0.83). Associations of CVH scores weakened, and population attributable fractions of LS7 reduced, from middle to old age; population attributable fraction of nonideal BP from 53% to 39%.

CONCLUSIONS

Except for BP, CVH is weakly associated with stroke at older ages. Prevention strategies for older adults should prioritize BP control but also enhance focus beyond traditional risk factors.

hUCMSCs Mitigate LPS-Induced Trained Immunity in Ischemic Stroke

Innate immune memory is a part of the innate immune system that facilitates the elimination of pathogens. However, it may exacerbate neuropathology. In this study, we found that innate immune memory is detrimental in stroke, because it promotes the acute immune response and exacerbates ischemic infarcts. Mesenchymal stem cell therapy has been widely studied for its therapeutic potential in various diseases including stroke, but whether it diminishes innate immune memory has not been studied. Here, our study demonstrates that, after the activation of innate immune memory by lipopolysaccharide, mesenchymal stem cell therapy can diminish innate immune memory though down-regulation of H3 methylation and subsequently protect against stroke. Our results demonstrate that innate immune memory is detrimental in stroke, and we describe a novel potential therapeutic target involving the use of mesenchymal stem cells to treat stroke patients.

Can we stop the stroke tsunami? Mitigating the barriers, amplifying the facilitators

In this narrative review article, by critically appraising the Global Burden of Disease 1990-2017 data on stroke and currently used primary stroke prevention strategies, we show that the global burden of stroke will continue to rise unless new primary stroke and cardiovascular disease (CVD) prevention strategies are urgently implemented. We provide an overview of the advantages and disadvantagesof population-wide and high CVD risk prevention strategies and mobile technologies available for stroke and CVD prevention on individual and population levels. Our recent NZ pilot RCT demonstrated the feasibility, consumer acceptability, motivational value and a clinically important, albeit statistically non-significant, behaviour change, improvement in diet, and awareness of stroke symptoms. We also identify and discuss causes for failure in the currently used primary stroke and CVD prevention strategies and emphasise the importance of complementary use of population-wide and elevated CVD risk strategies (including polypill interventions with blood pressure and lipid-lowering off-patent medications in middle-aged adults with elevated CVD risk) with motivational population-wide strategy to manage lifestyle and behavioural risk factors regardless of the level of stroke risk. The best mix of population-wide and elevated CVD risk-targeted strategiesfor primary stroke and CVD prevention remains to be determined.

Improvement of cerebral ischemia/reperfusion injury by daucosterol palmitate-induced neuronal apoptosis inhibition via PI3K/Akt/mTOR signaling pathway

Traditional Chinese medicine has growing importance in the treatment of ischemia stroke due to its abundance and low drug resistance. In this study, we aim to investigate the therapeutic potential of daucosterol palmitate against ischemia stroke, as well as its neuro-protective mechanism. The dose-response effects of daucosterol palmitate in the protection from brain damage were evaluated in a cerebral ischemia/reperfusion (I/R) rat model. The correlation of neuro-protective effects of daucosterol palmitate with apoptosis inhibition was examined and the possible signaling targets were identified. Our findings revealed that daucosterol palmitate treatment after 2 h' ischemia significantly lowered brain damage, and neuronal cell apoptosis caused by I/R injury in a dose-response mode (20, 40 and 80 mg/kg). Western blot analysis indicated that daucosterol palmitate could reverse the effects of I/R injury on protein expression of PI3K and mTOR, and phosphorylation of Akt. Contrarily, inactivation of PI3K using wortmannin dramatically antagonized the effect of daucosterol palmitate for I/R injury. With these findings, it supports the application potential of daucosterol palmitate in the treatment of ischemia stroke. Besides, the PI3K/Akt/mTOR pathway might be potential cellular targets for daucosterol palmitate.

Effects of statin therapy on outcomes of ischemic stroke: a real-world experience in Brazil

BACKGROUND

Statin therapy has become one of the most important advances in stroke secondary prevention.

OBJECTIVE

To provide evidence from real-world data for evaluating detailed associations between secondary prevention of stroke and statin use in Brazil.

METHODS

We conducted a prospective cohort study including consecutive patients diagnosed with an ischemic stroke. Subjects were classified into non-statin, simvastatin 20 mg, simvastatin 40 mg, and high-potency statin groups. We also registered the onset of statin therapy, previous use of statins, the adherence to medication, and if there was discontinuation of the therapy. After two years, the functional outcome, stroke recurrence, major cardiovascular events, and mortality were assessed.

RESULTS

Among the 513 patients included in our cohort, there were 96 (18.7%) patients without statins, 169 (32.9%) with simvastatin 20 mg, 202 (39.3%) with simvastatin 40 mg, and 46 (9.0%) with high-potency statins. Patients without statins were at increased risk of stroke recurrence and worse functional outcomes. Concerning etiology, evidence of beneficial use of statins was observed in cases of large-artery atherosclerosis, small-vessel occlusion, and stroke of undetermined cause. Those who presented poor adherence to statins or discontinuation of the treatment had worse prognosis after stroke whereas the early onset of statins use was associated with better outcomes. Patients with simvastatin 40 mg and high-potency statins presented the best functional recovery throughout the follow-up.

CONCLUSIONS

Statins play an important role in the treatment of ischemic stroke, preventing stroke recurrence and cardiovascular events, and improving functional performance.

Hypoxia-preconditioned olfactory mucosa mesenchymal stem cells abolish cerebral ischemia/reperfusion-induced pyroptosis and apoptotic death of microglial cells by activating HIF-1α

Microglial cells are the first line immune cells that initiate inflammatory responses following cerebral ischemia/reperfusion(I/R) injury. Microglial cells are also associated with a novel subtype of pro-inflammatory programmed cell death known as pyroptosis. Research has been directed at developing treatments that modulate inflammatory responses and protect against cell death caused by cerebral I/R. Key among such treatments include mesenchymal stem cell (MSC) therapy. A unique type of MSC termed olfactory mucosa mesenchymal stem cell (OM-MSC) confers neuroprotection by promoting the secretion of paracrine factors, and neuroprotection. This study investigated whether hypoxic OM-MSCs could inhibit microglial cell death upon I/R insult in vitro. A traditional oxygen-glucose deprivation/reperfusion (OGD/R) model, analogous to I/R, was established. Results showed that OGD/R induced apoptosis and pyroptosis in microglial cells while hypoxia in OM-MSCs significantly attenuated these effects. Moreover, the effects of OM-MSCs were mediated by Hypoxia-inducible factor 1-alpha (HIF-1α). Taken together, these findings reveal that hypoxia-preconditioned OM-MSC inhibits pyroptotic and apoptotic death of microglial cell in response to cerebral ischemia/reperfusion insult by activating HIF-1α in vitro.

The global burden of neurological disorders: translating evidence into policy

Neurological disorders are the leading cause of disability and the second leading cause of death worldwide. In the past 30 years, the absolute numbers of deaths and people with disabilities owing to neurological diseases have risen substantially, particularly in low-income and middle-income countries, and further increases are expected globally as a result of population growth and ageing. This rise in absolute numbers of people affected suggests that advances in prevention and management of major neurological disorders are not sufficiently effective to counter global demographic changes. Urgent measures to reduce this burden are therefore needed. Because resources for health care and research are already overstretched, priorities need to be set to guide policy makers, governments, and funding organisations to develop and implement action plans for prevention, health care, and research to tackle the growing challenge of neurological disorders.

Treadmill exercise promotes neurogenesis and myelin repair via upregulating Wnt/β‑catenin signaling pathways in the juvenile brain following focal cerebral ischemia/reperfusion

Physical exercise has a neuroprotective effect and is an important treatment after ischemic stroke. Promoting neurogenesis and myelin repair in the penumbra is an important method for the treatment of ischemic stroke. However, the role and potential mechanism of exercise in neurogenesis and myelin repair still needs to be clarified. The goal of the present study was to ascertain the possible effect of treadmill training on the neuroprotective signaling pathway in juvenile rats after ischemic stroke. The model of middle cerebral artery occlusion (MCAO) in juvenile rats was established and then the rats were randomly divided into 9 groups. XAV939 (an inhibitor of the Wnt/β‑catenin pathway) was used to confirm the effects of the Wnt/β‑catenin signaling pathway on exercise‑mediated neurogenesis and myelin repair. Neurological deficits were detected by modified neurological severity score, the injury of brain tissue and the morphology of neurons was detected by hematoxylin‑eosin staining and Nissl staining, and the infarct volume was detected by 2,3,5‑triphenyl tetrazolium chloride staining. The changes in myelin were observed by Luxol fast blue staining. The neuron ultrastructure was observed by transmission electron microscopy. Immunofluorescence and western blots analyzed the molecular mechanisms. The results showed that treadmill exercise improved neurogenesis, enhanced myelin repair, promoted neurological function recovery and reduced infarct volume. These were the results of the upregulation of Wnt3a and nucleus β‑catenin, brain‑derived neurotrophic factor (BDNF) and myelin basic protein (MBP). In addition, XAV939 inhibited treadmill exercise‑induced neurogenesis and myelin repair, which was consistent with the downregulation of Wnt3a, nucleus β‑catenin, BDNF and MBP expression, and the deterioration of neurological function. In summary, treadmill exercise promotes neurogenesis and myelin repair by upregulating the Wnt/β‑catenin signaling pathway, to improve the neurological deficit caused by focal cerebral ischemia/reperfusion.

Completeness of case ascertainment in Swedish hospital-based stroke registers

BACKGROUND

There is a worldwide development toward using data from hospital-based stroke registers to estimate epidemiological trends. However, incomplete case ascertainment may cause selection bias. We examined the completeness of case ascertainment and selection bias in two hospital-based Swedish stroke registers.

METHODS

First-ever stroke cases between March 2015 and February 2016 in the catchment area of Skåne University Hospital, Lund, Sweden, were included from multiple overlapping sources: two hospital-based stroke registers, Riksstroke-Lund and Lund Stroke Register (LSR); local outpatient and inpatient registers; primary care registers; and autopsy registers. The resulting population-based cohort was used as reference to assess completeness of case ascertainment and patient characteristics in Riksstroke-Lund and LSR.

RESULTS

In total, 400 stroke patients were identified. Riksstroke-Lund detected 328 (82%) patients, whereas LSR detected 363 (91%). Patients undetected by hospital-based registers had higher 28-day case fatality than those detected (44% vs 9%; P = .001). Patients only detected in primary care (n = 11) more often lived in healthcare facilities compared with those detected by hospital-based registers (57% vs 7%; P = .001). Patients not detected by Riksstroke-Lund, but detected by population-based sources, had less severe strokes (median NIHSS 3 vs 5; P = .013).

CONCLUSIONS

Some first-ever stroke patients, such as those with high early case fatality and those with mild stroke, may go undetected with hospital-based screening used in clinical stroke registers. This can result in selection bias due to not identifying specific groups of patients including some with high early case fatality and those living in healthcare facilities.

Factors Associated With 90-Day Readmission After Stroke or Transient Ischemic Attack

Background and Purpose—

Readmissions after stroke are common and appear to be associated with comorbidities or disability-related characteristics. In this study, we aimed to determine the patient and health-system level factors associated with all-cause and unplanned hospital readmission within 90 days after acute stroke or transient ischemic attack (TIA) in Australia.

Methods—

We used person-level linkages between data from the Australian Stroke Clinical Registry (2009–2013), hospital admissions data and national death registrations from 4 Australian states. Time to first readmission (all-cause or unplanned) for discharged patients was examined within 30, 90, and 365 days, using competing risks regression to account for deaths postdischarge. Covariates included age, stroke severity (ability to walk on admission), stroke type, admissions before stroke/TIA and the Charlson Comorbidity Index (derived from International Statistical Classification of Diseases and Related Health Problems, Tenth Revision , [Australian modified] coded hospital data in the preceding 5 years).

Results—

Among the 13 594 patients discharged following stroke/TIA (45% female; 65% ischemic stroke; 11% intracerebral hemorrhage; 4% undetermined stroke; and 20% TIA), 25% had an all-cause readmission and 15% had an unplanned readmission within 90 days. In multivariable analyses, the factors independently associated with a greater risk of unplanned readmission within 90 days were being female (subhazard ratio, 1.13 [95% CI, 1.03–1.24]), greater Charlson Comorbidity Index scores (subhazard ratio, 1.11 [95% CI, 1.09–1.12]) and having an admission ≤90 days before the index event (subhazard ratio, 1.85 [95% CI, 1.59–2.15]). Compared with being discharged to rehabilitation or aged care, those who were discharged directly home were more likely to have an unplanned readmission within 90 days (subhazard ratio, 1.44 [95% CI, 1.33–1.55]). These factors were similar for readmissions within 30 and 365 days.

Conclusions—

Apart from comorbidities and patient-level characteristics, readmissions after stroke/TIA were associated with discharge destination. Greater support for transition to home after stroke/TIA may be needed to reduce unplanned readmissions.

Visit-to-Visit Variability of Lipids Measurements and the Risk of Stroke and Stroke Types: A Prospective Cohort Study

BACKGROUND AND PURPOSE

Previous studies suggested increased visit-to-visit variability of total cholesterol (TC) is associated with stroke. This study aimed to investigate the associations of various lipids measurements variability and the risk of stroke and stroke type (ischemic and hemorrhagic stroke).

METHODS

Fifty-one thousand six hundred twenty participants in the Kailuan Study without history of myocardial infarction, stroke, and cancer who underwent three health examinations during 2006 to 2010 were followed for incident stroke. Variability in TC, triglycerides, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) measurements were measured using the coefficient of variation (CV), standard deviation (SD), variability independent of the mean (VIM), and average real variability (ARV).

RESULTS

During a median of 6.04 years of follow-up, 1,189 incident stroke (1,036 ischemic and 160 hemorrhagic stroke) occurred. In the multivariable-adjusted model, the hazard ratio (HR) comparing participants in the highest versus lowest quartile of CV of HDL-C were 1.21 (95% confidence interval [CI], 1.02 to 1.45; P for trend=0.013) for ischemic stroke. The highest quartile of CV of LDL-C was associated with 2.17-fold risk of hemorrhagic stroke (HR, 2.17; 95% CI, 1.25 to 3.75; P for trend=0.002) compared with the lowest quartile. We did not observe any significant association between TC and triglycerides variability with any of stroke. Consistent.

RESULTS

were obtained when calculating variability index using SD, VIM, or ARV.

CONCLUSIONS

These findings suggest the high visit-to-visit HDL-C and LDL-C variability were associated with an increased incidence of ischemic and hemorrhagic stroke, respectively.

Role of Metallothionein-1 and Metallothionein-2 in the Neuroprotective Mechanism of Sevoflurane Preconditioning in Mice

This study investigated the protective effects and mechanisms of sevoflurane preconditioning (SPC) on neurons in ischemic mice. After SPC, mice were subjected to middle cerebral artery occlusion (MCAO). Cerebral infarction area, cell apoptosis, and metallothionein-1 (MT-1) and metallothionein-2 (MT-2) expressions in MCAO mice were analyzed. Mouse primary neurons were isolated and cultured to determine the location of metallothioneins (MTs) using immunofluorescence. Neurons transfected with MT-siRNA, exogenous MTs, or sh-MTF-1 were subjected to SPC and/or oxygen-glucose deprivation (OGD), and MT-1/MT-2 expression and neurotoxin release were assayed. Meanwhile, neurons were treated with the nitric oxide donor SNAP, degraded SNAP, or the peroxide initiator paraquat, and alterations in MT-1/MT-2 expression and neurotoxicity release were observed. SPC attenuated neuronal injury and apoptosis in MCAO mice. SPC could protect neurons against OGD injury and resulted in upregulated MT-1/MT-2 expression. MT-siRNA transfection led to the downregulated expression of MT-1/MT-2 and increased neurotoxicity, and the expression patterns of these neurons were different from those of neurons transfected with exogenous MTs. The knockdown of MTs could hinder the protective effect of SPC against OGD. Pretreatment with SNAP or paraquat could increase MTF-1 expression in the nucleus of neurons, protecting against OGD injury. The inhibition of nitric oxide and peroxide inhibited the protective role of SPC in OGD by downregulating MTF-1 expression. sh-MTF-1 transfection downregulated MT-1/MT-2 expression and enhanced neurotoxicity in neurons. SPC confers neuroprotection in focal cerebral ischemia mouse models by upregulating the expression of MT-1 and MT-2 by activating NO and peroxide and increasing MTF-1 expression in the nucleus.

[The possibility of using neuron-specific enolase as a biomarker in the acute period of stroke]

The article presents a review of the literature on neuron-specific enolase (NSE) as a biomarker of stroke. It is shown that NSE does not allow differentiation of the ischemic and hemorrhagic process in stroke, but is suitable for determining the extent of brain tissue destruction both in the first hours of stroke and in the dynamics. The HSE analysis can be useful for monitoring the course of the disease, control of the dynamics of the pathological process, including when the size of the lesion increases, for evaluating the effectiveness of therapy and as a prognostic biomarker.

Workforce requirements for comprehensive ischaemic stroke care in a developing country: the case of Saudi Arabia

BACKGROUND

Ischaemic stroke care requires a co-ordinated multi-disciplinary approach to optimise patient outcomes. Current care provision in Saudi Arabia is below international recommendations, and with increasing patient numbers, variable access to new therapies, and sub-optimal co-ordination of staff, the Kingdom's Ministry of Health has prioritised strategies to develop stroke care. Our objective was to use local epidemiological data to predict stroke incidence and to combine this with international staffing recommendations to estimate future staff requirements and their costs over a 10-year period.

METHODS

We researched existing stroke services and staff availability within Saudi Arabia to establish current provision, undertook epidemiological modelling to predict stroke incidence, and used international staffing recommendations for acute and rehabilitation services to develop a care pathway to provide state-of-the-art stroke services. This information was used to determine the additional staff requirements, and their costs, across the Kingdom.

RESULTS

Our research concluded that current staff numbers and services are inadequate to cope with the projected increase in the number of stroke cases. In order to provide acute and rehabilitation services which use the latest technologies, re-organisation of existing staff and services would be required, together with significant investment in new staff across several disciplines. An estimated additional 43.8 full-time equivalent stroke neurologists would be required, plus 53.5 full-time equivalent interventional neuroradiologists in addition to expansion of occupational therapy and psychology services. The total cost of additional staff over 10 years was estimated to be 862 390 778 Saudi Riyals ($229 970 874).

CONCLUSIONS

Providing high-quality care for ischaemic stroke patients would involve significant investment in new staff in Saudi Arabia. Further research is required on the applicability of international staffing ratios to countries where there is a significant workforce gap. Nevertheless, this analysis provides a framework to inform stroke care planning and can be adapted to other regions or countries.

Brain oscillatory activity as a biomarker of motor recovery in chronic stroke

In the present work, we investigated the relationship of oscillatory sensorimotor brain activity to motor recovery. The neurophysiological data of 30 chronic stroke patients with severe upper‐limb paralysis are the basis of the observational study presented here. These patients underwent an intervention including movement training based on combined brain–machine interfaces and physiotherapy of several weeks recorded in a double‐blinded randomized clinical trial. We analyzed the alpha oscillations over the motor cortex of 22 of these patients employing multilevel linear predictive modeling. We identified a significant correlation between the evolution of the alpha desynchronization during rehabilitative intervention and clinical improvement. Moreover, we observed that the initial alpha desynchronization conditions its modulation during intervention: Patients showing a strong alpha desynchronization at the beginning of the training improved if they increased their alpha desynchronization. Patients showing a small alpha desynchronization at initial training stages improved if they decreased it further on both hemispheres. In all patients, a progressive shift of desynchronization toward the ipsilesional hemisphere correlates significantly with clinical improvement regardless of lesion location. The results indicate that initial alpha desynchronization might be key for stratification of patients undergoing BMI interventions and that its interhemispheric balance plays an important role in motor recovery.

Multi-level community interventions for primary stroke prevention: A conceptual approach by the World Stroke Organization

The increasing burden of stroke and dementia emphasizes the need for new, well-tolerated and cost-effective primary prevention strategies that can reduce the risks of stroke and dementia worldwide, and specifically in low- and middle-income countries (LMICs).

 This paper outlines conceptual frameworks of three primary stroke prevention strategies: (a) the “polypill” strategy; (b) a “population-wide” strategy; and (c) a “motivational population-wide” strategy.

 (a) A polypill containing generic low-dose ingredients of blood pressure and lipid-lowering medications (e.g. candesartan 16 mg, amlodipine 2.5 mg, and rosuvastatin 10 mg) seems a safe and cost-effective approach for primary prevention of stroke and dementia.

 (b) A population-wide strategy reducing cardiovascular risk factors in the whole population, regardless of the level of risk is the most effective primary prevention strategy. A motivational population-wide strategy for the modification of health behaviors (e.g. smoking, diet, physical activity) should be based on the principles of cognitive behavioral therapy. Mobile technologies, such as smartphones, offer an ideal interface for behavioral interventions (e.g. Stroke Riskometer app) even in LMICs.

 (c) Community health workers can improve the maintenance of lifestyle changes as well as the adherence to medication, especially in resource poor areas. An adequate training of community health workers is a key point.

Conclusion

An effective primary stroke prevention strategy on a global scale should integrate pharmacological (polypill) and lifestyle modifications (motivational population-wide strategy) interventions. Side effects of such an integrative approach are expected to be minimal and the benefits among individuals at low-to-moderate risk of stroke could be significant. In the future, pragmatic field trials will provide more evidence.