Time filter

Source Type

Umeå, Sweden

Gu W.,Umea Stroke Center | Gu W.,Umea University | Gu C.,Umea Stroke Center | Jiang W.,Umea Stroke Center | Wester P.,Umea Stroke Center
Stem Cell Research | Year: 2010

Neurogenesis occurs in the cerebral cortex of adult rats after focal cerebral ischemia. Whether or not the newborn neurons could synthesize neurotransmitters is unknown. To elucidate such a possibility, a photothrombotic ring stroke model with spontaneous reperfusion was induced in adult male Wistar rats. The DNA duplication marker BrdU was repeatedly injected, and the rats were sacrificed at various times after stroke. To detect BrdU nuclear incorporation and various neurotransmitters, brain sections were processed for single/double immunocytochemistry and single/double/triple immunofluorescence. Stereological cell counting was performed to assess the final cell populations. At 48 h, 5 days, 7 days, 30 days, 60 days and 90 days after stroke, numerous cells were BrdU-immunolabeled in the penumbral cortex. Some of these were doubly immunopositive to the cholinergic neuron-specific marker ChAT or GABAergic neuron-specific marker GAD. As analyzed by 3-D confocal microscopy, the neurotransmitters acetylcholine and GABA were colocalized with BrdU in the same cortical cells. In addition, GABA was colocalized with the neuron-specific marker Neu N in the BrdU triple-immunolabeled cortical cells. This study suggests that the newborn neurons are capable of synthesizing the neurotransmitters acetylcholine and GABA in the penumbral cortex, which is one of the fundamental requisites for these neurons to function in the poststroke recovery. © 2009 Elsevier B.V. All rights reserved.

Johansson E.,Umea Stroke Center | Cuadrado-Godia E.,Neurovascular Research Group | Hayden D.,Materials University Hospital | Bjellerup J.,Umea Stroke Center | And 4 more authors.
Neurology | Year: 2016

Objective: We aimed to quantify the risk and predictors of ipsilateral ischemic stroke in patients with symptomatic carotid stenosis awaiting revascularization (carotid endarterectomy [CEA] or carotid artery stenting) by pooling individual patient data from recent prospective studies with high rates of treatment with modern stroke prevention medications. Methods: Data were included from 2 prospective hospital-based registries (Umeå, Barcelona) and one prospective population-based study (Dublin). Patients with symptomatic 50%-99% carotid stenosis eligible for carotid revascularization were included and followed for early recurrent ipsilateral stroke or retinal artery occlusion (RAO). Results: Of 607 patients with symptomatic 50%-99% carotid stenosis, 377 met prespecified inclusion criteria. Ipsilateral recurrent ischemic stroke/RAO risk pre-revascularization was 2.7% (1 day), 5.3% (3 days), 11.5% (14 days), and 18.8% (90 days). On bivariate analysis, presentation with a cerebral vs ocular event was associated with higher recurrent stroke risk (log-rank p 0.04). On multivariable Cox regression, recurrence was associated with older age (adjusted hazard ratio [HR] per 10-year increase 1.5, p 0.02) with a strong trend for association with cerebral (stroke/TIA) vs ocular symptoms (adjusted HR 2.7, p 0.06), but not degree of stenosis, smoking, vascular risk factors, or medications. Conclusions: We found high risk of recurrent ipsilateral ischemic events within the 14-day time period currently recommended for CEA. Randomized trials are needed to determine the benefits and safety of urgent vs subacute carotid revascularization within 14 days after symptom onset. © 2016 American Academy of Neurology.

Discover hidden collaborations