FRCPC; for the VISION study groupBackground and Purpose-The risk of a recurrent stroke after transient ischemic attack (TIA) or minor stroke is high.Clinical trials are needed to assess acute treatment options in these patients. We sought to evaluate the type of recurrent events and to identify which subsets of patients are at risk for recurrent events. Methods-One hundred and eighty patients with TIA or minor stroke were examined within 12 hours and underwent brain MRI within 24 hours. Any neurological deterioration was recorded, and a combination of clinical and MRI factors were used to create a combined event classification. Subgroups of patients analyzed included classical TIA, patients with NIHSSϭ0, and patients with NIHSS Ͼ0 in ED. Results-Overall there were 38 events in 36 patients (20% event rate); 20 were symptomatic and 18 were silent (only evident because of the follow up MRI). 18/20 (90%) symptomatic events were associated with progression of presenting symptoms, compared to 2/20 (10%) with a clear recurrent stroke distinct from the original event. We found a low risk of recurrent stroke among classical definition TIA patients (1.1%). Patients with an NIHSSϭ0 in the ED, had an intermediate event rate (6.6%) between TIA (classical -1.1%) and NIHSS Ͼ0 (14.4%; 2 test for trend, Pϭ0.02). All clinical categories of patient (TIA, stroke, NIHSSϭ0) accumulated silent lesions on MRI. Conclusions-Most events were classified as stroke progression or infarct growth rather than a recurrent stroke. A low risk of recurrence was found in patients with classical TIA and those with no neurological deficits on initial assessment.

Recessive mutations in WD repeat domain 62 (WDR62) cause microcephaly and a wide spectrum of severe brain malformations. Disruption of the mouse ortholog results in microcephaly underlain by reduced proliferation of neocortical progenitors during late neurogenesis, abnormalities in asymmetric centrosome inheritance leading to neuronal migration delays, and altered neuronal differentiation. Spindle pole localization of WDR62 and mitotic progression are defective in patient-derived fibroblasts, which, similar to mouse neocortical progenitors, transiently arrest at prometaphase. Expression of WDR62 is closely correlated with components of the chromosome passenger complex (CPC), a key regulator of mitosis. Wild type WDR62, but not disease-associated mutant forms, interacts with the CPC core enzyme Aurora kinase B and staining of CPC components at centromeres is altered in patient-derived fibroblasts. Our findings demonstrate critical and diverse functions of WDR62 in neocortical development and provide insight into the mechanisms by which its disruption leads to a plethora of structural abnormalities.

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Background Slow and asymmetric gait post-stroke may reduce the accuracy of accelerometers (e.g. ActiGraph [AG]) to measure activity. Objectives To (1) determine the validity of AG step counts post-stroke; (2) develop guidelines for low frequency extension filter (LFE) use; and (3) determine the feasibility of daily accelerometer wear. Methods Adults with (n = 33) and without stroke (n = 20) wore three devices for approximately 7 h on a single day: ankle AG, waist AG, and a reference accelerometer at the ankle (REFA). AG step counts processed with and without the LFE were compared to REFA with paired difference tests. Agreement was measured with intraclass correlation coefficients (ICC). Relationships between error (AG - REFA) and motor impairment and gait performance were plotted to determine a threshold for LFE application. A feasibility questionnaire was distributed to participants to investigate the applicability of the AG in clinical populations. Results Step counts from ankle AG in the stroke group (p = 0.53) and waist AG in the healthy group (p = 0.10) were similar to REFA. Waist AG under-counted, and ankle and waist AG with LFE over-counted steps in the stroke group (all p < 0.0001). ICC ranged from 0.70 to 0.82 (stroke) and 0.79-0.92 (healthy). Ankle AG error and stance time symmetry (stroke) were correlated (r = 0.41, p = 0.02); however, no threshold for LFE application was revealed. Ankle AG was rated very comfortable by 26/33 participants with stroke and 12/20 healthy participants. Conclusions The AG worn at the unaffected ankle without LFE produced the most accurate step count in people with stroke. We were unable to establish guidelines for LFE use.