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While women have greater incidence of dementia, men have higher prevalence of vascular risk factors. This study examined sex differences in risk of screening positive for cognitive impairment after stroke. Ischemic stroke/TIA patients (N = 5969) participated in this prospective, multi-centered study, which screened for cognitive impairment using a validated brief screen. Men showed a higher risk of screening positive for cognitive impairment after adjusting for age, education, stroke severity, and vascular risk factors, suggesting that other factors may be contributing to increased risk among men (OR = 1.34, CI 95% [1.16, 1.55], p < 0.001). The effect of sex on cognitive impairment after stroke warrants further attention.

BackgroundThe DOC screen was developed to identify Depression, Obstructive sleep apnea, and Cognitive impairment (“DOC” comorbidities) after stroke. Each component has its own score, but additional information may be gained from the time to complete the screen. Cognitive screening completion time is rarely used as an outcome measure. We assessed the added value of using DOC screen completion time as a predictor of impairment on detailed cognitive assessments.MethodsConsecutive English-speaking new referrals to the stroke prevention clinic were consented to participate in detailed neuropsychological testing (n=437). DOC screen scores and times were compared to cognitive test scores using multiple linear regression and receiver operating characteristic (ROC) analysis. All linear regression analyses controlled for age, sex, years of education, and functional outcome as assessed by the modified Rankin score.ResultsAverage completion time for the DOC screen was 3.8 ± 1.3 minutes. After accounting for age, sex and cognitive screen score, completion time was a significant independent predictor, of speed of processing (p = .002, 95% CI: -0.016 to -0.004), verbal fluency (p < .001, CI: -0.012 to -0.006) and executive (p = .004, CI: -0.006 to -0.001), but not memory, function. Completion time above 5.5 minutes (332.5 seconds) was associated with a high likelihood of impairment on gold standard executive (likelihood ratios 3.9-5.2) and speed of processing (likelihood ratio = 5.2) tasks.ConclusionsDOC screen completion time is easy to collect in routine care and is independently associated with speed of processing, language and executive dysfunctions after stroke. People who take more than 5.5 minutes to complete the DOC screen are likely to have deficits in executive functioning and speed of processing. These domains can be challenging to screen for in stroke survivors, and this measure provides a simple, clinically feasible method to screen for these under-appreciated concerns.Clinical Trials Registration Identifier:NCT02363114Clinical Trials URL:https://clinicaltrials.gov/ct2/show/NCT02363114

Intravenous thrombolysis with alteplase bolus followed by infusion is a global standard of care for patients with acute ischaemic stroke. We aimed to determine whether tenecteplase given as a single bolus might increase reperfusion compared with this standard of care.In this multicentre, open-label, parallel-group, registry-linked, randomised, controlled trial (AcT), patients were enrolled from 22 primary and comprehensive stroke centres across Canada. Patients were eligible for inclusion if they were aged 18 years or older, with a diagnosis of ischaemic stroke causing disabling neurological deficit, presenting within 4·5 h of symptom onset, and eligible for thrombolysis per Canadian guidelines. Eligible patients were randomly assigned (1:1), using a previously validated minimal sufficient balance algorithm to balance allocation by site and a secure real-time web-based server, to either intravenous tenecteplase (0·25 mg/kg to a maximum of 25 mg) or alteplase (0·9 mg/kg to a maximum of 90mg; 0·09 mg/kg as a bolus and then a 60 min infusion of the remaining 0·81 mg/kg). The primary outcome was the proportion of patients who had a modified Rankin Scale (mRS) score of 0-1 at 90-120 days after treatment, assessed via blinded review in the intention-to-treat (ITT) population (ie, all patients randomly assigned to treatment who did not withdraw consent). Non-inferiority was met if the lower 95% CI of the difference in the proportion of patients who met the primary outcome between the tenecteplase and alteplase groups was more than -5%. Safety was assessed in all patients who received any of either thrombolytic agent and who were reported as treated. The trial is registered with ClinicalTrials.gov, NCT03889249, and is closed to accrual.Between Dec 10, 2019, and Jan 25, 2022, 1600 patients were enrolled and randomly assigned to tenecteplase (n=816) or alteplase (n=784), of whom 1577 were included in the ITT population (n=806 tenecteplase; n=771 alteplase). The median age was 74 years (IQR 63-83), 755 (47·9%) of 1577 patients were female and 822 (52·1%) were male. As of data cutoff (Jan 21, 2022), 296 (36·9%) of 802 patients in the tenecteplase group and 266 (34·8%) of 765 in the alteplase group had an mRS score of 0-1 at 90-120 days (unadjusted risk difference 2·1% [95% CI - 2·6 to 6·9], meeting the prespecified non-inferiority threshold). In safety analyses, 27 (3·4%) of 800 patients in the tenecteplase group and 24 (3·2%) of 763 in the alteplase group had 24 h symptomatic intracerebral haemorrhage and 122 (15·3%) of 796 and 117 (15·4%) of 763 died within 90 days of starting treatment INTERPRETATION: Intravenous tenecteplase (0·25 mg/kg) is a reasonable alternative to alteplase for all patients presenting with acute ischaemic stroke who meet standard criteria for thrombolysis.Canadian Institutes of Health Research, Alberta Strategy for Patient Oriented Research Support Unit.

The ability to resolve an approach-avoidance conflict is critical to adaptive behavior. The ventral CA3 (vCA3) and CA1 (vCA1) subfields of the ventral hippocampus (vHPC) have been shown to facilitate avoidance and approach behavior, respectively, in the face of motivational conflict, but the neural circuits by which this subfield-specific regulation is implemented is unknown. We demonstrate that two distinct pathways from these subfields to lateral septum (LS) contribute to this divergent control. In Long-Evans rats, chemogenetic inhibition of the vCA3- LS caudodorsal (cd) pathway potentiated approach towards a learned conflict-eliciting stimulus, while inhibition of the vCA1-LS rostroventral (rv) pathway potentiated approach non-specifically. Additionally, vCA3-LScd inhibited animals were less hesitant to explore food during environmental uncertainty, while the vCA1- LSrv inhibited animals took longer to initiate food exploration. These findings suggest that the vHPC influences multiple behavioral systems via differential projections to the LS, which in turn send inhibitory projections to motivational centres of the brain.

Oligodendrogliomas are lower-grade, slow-growing gliomas that are ultimately fatal. Although driver mutations are known, the mechanisms underlying their signature slow growth rates are poorly understood. We found evidence for intra-tumoral interactions between neoplastic and non-neoplastic cells in oligodendroglioma tissues. To further study these cell interactions, we used two patient-derived oligodendroglioma cell lines of lower and higher aggressivity. Both oligodendroglioma cell lines released extracellular vesicles that had cytotoxic effects on non-neoplastic and neoplastic cells, but each had distinct vesicular proteomes. Consistent with extracellular vesicles mediating growth inhibitory effects in oligodendrogliomas, higher expression levels of several extracellular vesicle biogenesis genes (SMPD3, TSG101, STAM1) correlates with longer survival in oligodendroglioma patients. Furthermore, SMPD3 overexpression slows oligodendroglioma cell growth in culture. Conversely, SMPD3 knockdown enhances oligodendroglioma proliferation in vitro, in murine xenografts, and in human cerebral organoid co-cultures. Oligodendroglioma-derived extracellular vesicles thus mediate tumor cell microenvironmental interactions that contribute to low aggressivity.

Oligodendrogliomas are lower-grade, slow-growing gliomas that are ultimately fatal. Although driver mutations are known, the mechanisms underlying their signature slow growth rates are poorly understood. We found evidence for intra-tumoral interactions between neoplastic and non-neoplastic cells in oligodendroglioma tissues. To further study these cell interactions, we used two patient-derived oligodendroglioma cell lines of lower and higher aggressivity. Both oligodendroglioma cell lines released extracellular vesicles that had cytotoxic effects on non-neoplastic and neoplastic cells, but each had distinct vesicular proteomes. Consistent with extracellular vesicles mediating growth inhibitory effects in oligodendrogliomas, higher expression levels of several extracellular vesicle biogenesis genes (SMPD3,TSG101, STAM1) correlates with longer survival in oligodendroglioma patients. Furthermore, SMPD3 overexpression slows oligodendroglioma cell growth in culture. Conversely, SMPD3 knockdown enhances oligodendroglioma proliferation in vitro, in murine xenografts, and in human cerebral organoid co-cultures. Oligodendroglioma-derived extracellular vesicles thus mediate tumor cell microenvironmental interactions that contribute to low aggressivity.