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While few studies investigated the incidence of stroke in Iran, no Iranian cohort has estimated the standardized-incidence rate and early fatality of first-ever-stroke subtypes along with associated factors.Golestan Cohort Study is a prospective study launched in northeastern Iran in 2004, including 50,045 individuals aged 40-75 at baseline. Age-standardized incidence rate of first-ever-stroke was calculated per 100,000 person-years, according to World Standard Population. The 28-day case fatality was calculated by dividing the number of fatal first-ever-stroke during the first 28 days by total events. Cox proportional hazard models were conducted to assess incidence and fatality risk factors. We used Population Attributable Fractions to estimate the incidence and early fatality proportions reduced by ideal risk factor control.1,135 first-ever-strokes were observed during 8.6 (median) years follow-up. First-ever-stroke standardized incidence rate was estimated 185.2 (95% CI: 173.2-197.2) per 100,000 person-years. The 28-day case fatality was 44.1% (95% CI: 40.4-48.2). Hypertension and pre-stroke physical activity were the strongest risk factors associated with first-ever-stroke incidence (Hazard ratio: 2.83; 2.47-3.23) and 28-day case fatality (Hazard ratio: 0.59; 0.44-0.78), respectively. Remarkably, opium consumption was strongly associated with hemorrhagic stroke incidence (Hazard ratio: 1.52; 1.04-2.23) and ischemic stroke fatality (Hazard ratio: 1.44; 1.01-2.09). Overall, modifiable risk factors contributed to 83% and 61% of first-ever-stroke incidence and early fatality, respectively.Efficient risk factor control can considerably reduce stroke occurrence and fatality in our study. Establishing awareness campaigns and 24-hour stroke units seem necessary for improving the stroke management in this area.

Background: There has been increasing attention on cerebrovascular events (CVEs) following SARS-CoV-2. The goal of this study was to better depict the short-term risk of CVEs and its associated factors among SARS-CoV-2 hospitalized patients. Methods: This multicenter, multinational observational study includes hospitalized SARS-CoV-2 patients from North and South America (United States, Canada, and Brazil), Europe (Greece, Italy, Finland, and Turkey), Asia (Lebanon, Iran, and India), and Oceania (New Zealand). The outcome was the risk of subsequent CVEs. The counts and clinical details of the patients with and without a CVE were received according to a predefined protocol. Quality, risk of bias, and heterogeneity assessments were conducted according to ROBINS-E and Cochrane Q-test. The risk of subsequent CVEs was estimated for individual states/districts, countries, continents, and within industrialized countries through meta-analyses with random effect models. Bivariate logistic regression was used to determine the parameters with predictive outcome value. The study was reported according to the STROBE, MOOSE, and EQUATOR guidelines. Findings: We received data from 26,133 hospitalized SARS-CoV-2 patients from 99 tertiary centers in 65 states/districts. A total of 17,774 patients were included in meta-analyses. Among them, 156 patients had a CVE complication—123(78·8%) ischemic stroke, 27(17·3%) intracerebral/subarachnoid hemorrhage, and 6(3·8%) cerebral sinus thrombosis. The meta-analyses indicated an overall 0·3%-1·2% risk of CVEs. Dependency on a ventilator and the presence of ischemic heart disease were predictive of CVEs. Interpretation: Although there is an increased risk of CVEs among SARS-CoV-2 patients, the risk is comparable to other viral infections and critical conditions. Funding: None Declaration of Interest: Neither I (Ramin Zand, corresponding author) nor any of the co-authors have a financial, commercial, legal, or professional relationship with other organizations, or with the people working with them, that could influence our presented research. Ethical Approval: The study receivedapproval bythe Institutional Review Board of Geisinger Health System and other participating institutions when it was required.

BACKGROUND Although intracerebral hemorrhage (ICH) is more common among African-Americans, data on the burden of cerebral microbleeds (CMBs) among different races is limited. The purpose of this study is to compare the number, associated factors, and topography of CMBs between African-American and Caucasian populations in the Mid-South United States. METHODS Using natural language processing, we extracted all brain MRIs performed during a 2-year period (2012-2013) when the report indicated the presence of CMB. All the extracted MRI studies were evaluated for number and location of CMBs, prior stroke, and deep white matter lesion. Negative binomial regression was used to model for the overdispersed count data. RESULTS A total 167 patients (mean age was 63 ± 15 years, 49% men, 77% African-American, median CMB count: 8) with 1 or more CMBs on their brain MRI were included in this study. There was no significant difference between the 2 groups in terms of CMB locations (P = .086), but there was a significant difference between African-American and Caucasian patients in terms of number of CMBs (16.5 ± 18 versus 6.5 ± 5.5, P < .001). The prevalence of multiple CMBs (CMBs ≥ 5) was similar among African-Americans and Caucasians (72% versus 55%, P = .062). After adjusting for potential confounders, the African-American race was not independently associated with a higher CMB burden (P = .073). CONCLUSION African-American race was not independently associated with a higher rate of CMB burden when compared to Caucasians after adjusting for potential confounders. We also did not observe a significant racial difference regarding the location and prevalence of multiple CMBs (CMBs ≥ 5).

There is mounting evidence supporting infection as an independent risk factor for ischemic stroke (IS), while preliminary data indicate that vaccination may prevent IS. We performed a systematic review and meta-analysis of available randomized clinical trials (RCTs) or prospective observational cohorts reporting associations of influenza vaccination (IV) and/or pneumococcal vaccination (PV) with IS. We identified a total of 12 studies (543,311 patients; 47.4% vaccinated). Vaccination was not related to the risk of IS (RR=1.06, 95%CI: 0.74-1.51, p=0.77), with no significant differences (p=0.26) among RCTs (RR=0.66, 95%CI: 0.30-1.47) and observational studies (RR=1.11, 95%CI: 0.76-1.61). Evidence of considerable heterogeneity was identified within observational studies (I2=98%), but not within RCTs (I2=0%). In subgroup analyses according to vaccination type, IV was associated with a significantly lower risk of IS (RR=0.87, 95%CI: 0.79-0.96, p=0.004) with moderate evidence of heterogeneity (I2=53%). No association was seen for PV (RR=1.38, 95%CI: 0.60-3.16, p=0.45), where considerable heterogeneity was identified (I2=97%). In the additional adjusted analyses of observational studies, vaccination tended to be associated with lower risk of IS (HRadjusted=0.87; 95%CI: 0.75-1.01; p=0.07). The findings of this meta-analysis indicate that IV may be associated with a lower risk of IS. This association was not reproduced for PV or the combination of two vaccines. Substantial heterogeneity was detected across observational studies for all outcome events, while moderate to low heterogeneity was identified across included RCTs. These preliminary findings require independent validation in large RCTs.

Background and Aims Data on the epidemiology of cerebral microbleeds (CMBs) among patients with ischemic stroke are limited. This study compared the number, associated factors, and topography of CMBs between African American and Caucasian ischemic stroke patients in the Mid-South United States. Method We evaluated consecutive ischemic stroke patients admitted to our tertiary stroke center, University of Tennessee Health Science Center, Memphis, Tennessee, in a two-year period. We analyzed T2*-weighted magnetic resonance images for the number, location, and topography of CMBs, as well as patients' demographic and clinical information. Results Among 760 ischemic stroke patients who were included (mean age was 62.1 ± 13.9 years, 51.4% men), 450 (59.2%) were African American. In comparison with Caucasians, African Americans were about five years younger ( P = .000) and had a higher rate of hypertension (80.9% vs. 74.5%, P = .036). Similarly, African Americans had a higher prevalence of diabetes mellitus ( P = .001). There was no significant difference between African-Americans and Caucasians in terms of CMBs presence and location. African Americans had a higher number of CMBs in comparison with Caucasians, but the difference was not significant. African Americans were more likely to have CMBs ≥5 ( P = .047). Although African American stroke patients had a higher rate of large confluent white matter lesions, there was no significant racial difference regarding the rate and severity of deep white matter lesions. Conclusion We did not observe any differences between African American and Caucasian patients with ischemic stroke patients regarding the presence, number, and location of CMBs. However, our results suggested that the prevalence of multiple CMBs (CMBs ≥5) might be higher among African American stroke patients.

Objective Despite improvements in treatment, stroke remains a leading cause of mortality and long-term disability. In this study, we leveraged administrative data to build predictive models of short- and long-term post-stroke all-cause-mortality. Methods The study was conducted and reported according to the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guideline. We used patient-level data from electronic health records, three algorithms, and six prediction windows to develop models for post-stroke mortality. Results We included 7144 patients from which 5347 had survived their ischemic stroke after two years. The proportion of mortality was between 8%(605/7144) within 1-month, to 25%(1797/7144) for the 2-years window. The three most common comorbidities were hypertension, dyslipidemia, and diabetes. The best Area Under the ROC curve(AUROC) was reached with the Random Forest model at 0.82 for the 1-month prediction window. The negative predictive value (NPV) was highest for the shorter prediction windows – 0.91 for the 1-month – and the best positive predictive value (PPV) was reached for the 6-months prediction window at 0.92. Age, hemoglobin levels, and body mass index were the top associated factors. Laboratory variables had higher importance when compared to past medical history and comorbidities. Hypercoagulation state, smoking, and end-stage renal disease were more strongly associated with long-term mortality. Conclusion All the selected algorithms could be trained to predict the short and long-term mortality after stroke. The factors associated with mortality differed depending on the prediction window. Our classifier highlighted the importance of controlling risk factors, as indicated by laboratory measures.

Background Stroke patients who have cerebral micro bleeds (CMBs) could be potentially at a greater risk for symptomatic intracerebral hemorrhage (sICH) than those patients without CMBs. The aim of our study was to investigate whether the presence and burden of CMBs are associated with post IVT sICH. Methods In this multicenter study, consecutive patients treated with intravenous tissue plasminogen activator were prospectively identified and analyzed. Patients without magnetic resonance imaging (MRI) within 24 hours of treatment were excluded. CMBs were defined as round or oval, hypointense lesions with associated blooming on T2*-weighted MRI up to 10 mm in diameter. Outcome measures included the occurrence of sICH or death. Results Of 672 patients with IVT (mean age 62 ± 14 years, 52% men, median admission NIHSS: 7 points), 103 patients had CMBs on T2*-MRI. Ten patients had more than 10, whereas the remaining 93 patients had 1-10 CMBs on T2*-MRI. The rates of sICH did not differ between patients with and patients without 1-10 CMBs (5.8% versus 3.5%; P = .27). However, sICH occurred more frequently ( P = .0009) in patients with > 10 CMBs (30%, 95% confidence interval [CI] by the adjusted Wald method: 10%-61%). After adjusting for potential confounders, the presence of >10 CMBs on T2*-MRI was independently ( P = .0004) associated with a higher likelihood for sICH (odds ratio [OR]:13.4, 95%CI:3.2-55.9). Conclusions Our findings indicate an increased risk of sICH after IVT when more than 10 CMBs are present.

No eligibility screening logs were kept in recent mechanical thrombectomy (MT) RCTs establishing safety and efficacy of endovascular reperfusion therapies for acute ischemic stroke (AIS). We sought to evaluate the potential eligibility for MT among consecutive AIS patients in a prospective international multicenter study. We prospectively evaluated consecutive AIS patients admitted in four tertiary-care stroke centers during a twelve-month period. Potential eligibility for MT was evaluated using inclusion criteria from MR CLEAN & REVASCAT. Our study population consisted of 1464 AIS patients (mean age 67±14years, 56% men, median admission NIHSS-score: 5, IQR: 3-10). A total of 123 (8%, 95% CI: 7%-10%) and 82 (6%, 95% CI: 5%-7%) patients fulfilled the inclusion criteria for MR CLEAN&REVASCAT respectively. No evidence of heterogeneity (p>0.100) was found in the eligibility for MT across the participating centers. Absence of proximal intracranial occlusion (69%) and hospital arrival outside the eligible time window (38% for MR CLEAN & 35% for REVASCAT) were the two most common reasons for ineligibility for MT. Our everyday clinical practice experience suggests that approximately one out of thirteen to seventeen consecutive AIS may be eligible for MT if inclusion criteria for MR CLEAN and REVASCAT are strictly adhered to.

Objective Transient cortical blindness (TCB) is a relatively rare but well-recognized complication following cardiovascular and cerebral angiography. Methods A 68-year-old male developed TCB following cerebral angiography along with punctate diffusion lesion evident on emergent magnetic resonance imaging (MRI). The patient received intravenous tissue plasminogen activator (IV-tPA) for suspected stroke. Results Follow-up MRI revealed diffuse hyperintensities in subarachnoid space in fluid-attenuated inversion recovery (FLAIR) sequence mostly in bilateral occipital lobes. Conclusion The finding on the FLAIR as described in this case is an indication of diffuse disruption of the blood–brain barrier perhaps secondary to cerebral angiography, high blood pressure, and IV-tPA. To the best of our knowledge, this is the first reported case of TCB with diffuse postcontrast FLAIR changes.

Myelin basic protein (MBP) represents a candidate autoantigen in multiple sclerosis (MS). We isolated MBP from normal and MS human white matter and purified six components (charge isomers) to compare the post-translational modifications on each. The sites and extent of methylation, deimination, and phosphorylation were documented for all tryptic peptides by mass spectrometry. We found that mono and dimethylated arginine 107 was increased in MS samples; deimination of arginine occurred at a number of sites and was elevated in MS; phosphorylation was observed in 10 peptides in normal samples but was greatly reduced or absent in most peptides from MS samples. Data obtained with MBP isolated from fresh brain obtained from a spontaneously demyelinating mouse model supported the view that the changes observed in human brain were probably related to pathogenesis of demyelination, i.e. we found decreased phosphorylation and decreased amounts of glycogen synthesis kinase in brain homogenates using specific antibodies. This study represents the first to define post-translational modifications in demyelinating disease and suggest an important role in pathogenesis.

The synthesis and characterization of two thermally stable polymers containing a polybenzimidazole and a ladder polymer structure are described. The tetraamino derivative of phenazine required for these syntheses was obtained by the reduction of the commercially available diamino, dinitro derivative of benzene. The polybenzimidazole polymer was synthesized by condensing tetraaminophenzine with terephthaldehyde in dimethylacetamide solvent. The resulting polymer had an intrinsic viscosity of 0.94 g/dl in methanesulfonic acid solvent. The TGA of the polymer showed it to be stable up to 4708C. The ladder polymer was prepared by reacting tetramainophenazine with dihydroquinone in polyphosphoric acid at a temperature of 1468C. The polymer formed a brittle, free-hanging film when cast from methanesulfonic acid. The molecule exhibited high degree of crystallinity and had a tendency to form dendritic-shaped structures. Doping with 15% iodine resulted in a conductivity of 9 £ 10 27 mho/cm. It was thermally stable in air, showing a 10% weight loss at 4108C. q 1999 Elsevier Science Ltd. All rights reserved.

The circular dichroism spectra of the ferri- and ferrocytochromes c derived from horse, beef, chicken, and turtle hearts have been measured over the wavelength range of 240-185 mμ. The spectra in this wavelength region of the ferri and ferro forms appear to be the same within experimental error and indicate that no gross conformational differences appear to exist between the oxidized and reduced forms. The upper limit of the apparent helix content has been estimated to be about 17% with a lower limit in the neighborhood of 10%. The presence of circular dichroism bands characteristic of α-helix conformations are observed along with bands characteristic of β structure. These data strongly suggest the presence of a small but real helical segment (s) in cytochrome c .