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Sample records for stroke induced brain

  1. Constraint-induced movement therapy promotes brain functional reorganization in stroke patients with hemiplegia.

    Science.gov (United States)

    Wang, Wenqing; Wang, Aihui; Yu, Limin; Han, Xuesong; Jiang, Guiyun; Weng, Changshui; Zhang, Hongwei; Zhou, Zhiqiang

    2012-11-15

    Stroke patients with hemiplegia exhibit flexor spasms in the upper limb and extensor spasms in the lower limb, and their movement patterns vary greatly. Constraint-induced movement therapy is an upper limb rehabilitation technique used in stroke patients with hemiplegia; however, studies of lower extremity rehabilitation are scarce. In this study, stroke patients with lower limb hemiplegia underwent conventional Bobath therapy for 4 weeks as baseline treatment, followed by constraint-induced movement therapy for an additional 4 weeks. The 10-m maximum walking speed and Berg balance scale scores significantly improved following treatment, and lower extremity motor function also improved. The results of functional MRI showed that constraint-induced movement therapy alleviates the reduction in cerebral functional activation in patients, which indicates activation of functional brain regions and a significant increase in cerebral blood perfusion. These results demonstrate that constraint-induced movement therapy promotes brain functional reorganization in stroke patients with lower limb hemiplegia.

  2. Constraint-induced movement therapy promotes brain functional reorganization in stroke patients with hemiplegia

    Science.gov (United States)

    Wang, Wenqing; Wang, Aihui; Yu, Limin; Han, Xuesong; Jiang, Guiyun; Weng, Changshui; Zhang, Hongwei; Zhou, Zhiqiang

    2012-01-01

    Stroke patients with hemiplegia exhibit flexor spasms in the upper limb and extensor spasms in the lower limb, and their movement patterns vary greatly. Constraint-induced movement therapy is an upper limb rehabilitation technique used in stroke patients with hemiplegia; however, studies of lower extremity rehabilitation are scarce. In this study, stroke patients with lower limb hemiplegia underwent conventional Bobath therapy for 4 weeks as baseline treatment, followed by constraint-induced movement therapy for an additional 4 weeks. The 10-m maximum walking speed and Berg balance scale scores significantly improved following treatment, and lower extremity motor function also improved. The results of functional MRI showed that constraint-induced movement therapy alleviates the reduction in cerebral functional activation in patients, which indicates activation of functional brain regions and a significant increase in cerebral blood perfusion. These results demonstrate that constraint-induced movement therapy promotes brain functional reorganization in stroke patients with lower limb hemiplegia. PMID:25337108

  3. AMPA receptor-induced local brain-derived neurotrophic factor signaling mediates motor recovery after stroke.

    Science.gov (United States)

    Clarkson, Andrew N; Overman, Justine J; Zhong, Sheng; Mueller, Rudolf; Lynch, Gary; Carmichael, S Thomas

    2011-03-09

    Stroke is the leading cause of adult disability. Recovery after stroke shares similar molecular and cellular properties with learning and memory. A main component of learning-induced plasticity involves signaling through AMPA receptors (AMPARs). We systematically tested the role of AMPAR function in motor recovery in a mouse model of focal stroke. AMPAR function controls functional recovery beginning 5 d after the stroke. Positive allosteric modulators of AMPARs enhance recovery of limb control when administered after a delay from the stroke. Conversely, AMPAR antagonists impair motor recovery. The contributions of AMPARs to recovery are mediated by release of brain-derived neurotrophic factor (BDNF) in periinfarct cortex, as blocking local BDNF function in periinfarct cortex blocks AMPAR-mediated recovery and prevents the normal pattern of motor recovery. In contrast to a delayed AMPAR role in motor recovery, early administration of AMPAR agonists after stroke increases stroke damage. These findings indicate that the role of glutamate signaling through the AMPAR changes over time in stroke: early potentiation of AMPAR signaling worsens stroke damage, whereas later potentiation of the same signaling system improves functional recovery.

  4. Regulatory T cells ameliorate tissue plasminogen activator-induced brain haemorrhage after stroke.

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    Mao, Leilei; Li, Peiying; Zhu, Wen; Cai, Wei; Liu, Zongjian; Wang, Yanling; Luo, Wenli; Stetler, Ruth A; Leak, Rehana K; Yu, Weifeng; Gao, Yanqin; Chen, Jun; Chen, Gang; Hu, Xiaoming

    2017-07-01

    Delayed thrombolytic treatment with recombinant tissue plasminogen activator (tPA) may exacerbate blood-brain barrier breakdown after ischaemic stroke and lead to lethal haemorrhagic transformation. The immune system is a dynamic modulator of stroke response, and excessive immune cell accumulation in the cerebral vasculature is associated with compromised integrity of the blood-brain barrier. We previously reported that regulatory T cells, which function to suppress excessive immune responses, ameliorated blood-brain barrier damage after cerebral ischaemia. This study assessed the impact of regulatory T cells in the context of tPA-induced brain haemorrhage and investigated the underlying mechanisms of action. The number of circulating regulatory T cells in stroke patients was dramatically reduced soon after stroke onset (84 acute ischaemic stroke patients with or without intravenous tPA treatment, compared to 115 age and gender-matched healthy controls). Although stroke patients without tPA treatment gradually repopulated the numbers of circulating regulatory T cells within the first 7 days after stroke, post-ischaemic tPA treatment led to sustained suppression of regulatory T cells in the blood. We then used the murine suture and embolic middle cerebral artery occlusion models of stroke to investigate the therapeutic potential of adoptive regulatory T cell transfer against tPA-induced haemorrhagic transformation. Delayed administration of tPA (10 mg/kg) resulted in haemorrhagic transformation in the ischaemic territory 1 day after ischaemia. When regulatory T cells (2 × 106/mouse) were intravenously administered immediately after delayed tPA treatment in ischaemic mice, haemorrhagic transformation was significantly decreased, and this was associated with improved sensorimotor functions. Blood-brain barrier disruption and tight junction damages were observed in the presence of delayed tPA after stroke, but were mitigated by regulatory T cell transfer. Mechanistic

  5. An fMRI study of acupuncture-induced brain activation of aphasia stroke patients.

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    Li, Geng; Yang, Edward S

    2011-01-01

    This investigation aims to test the effect of acupuncture on word generation activation (WGA) in post-stroke aphasia patients. Seven vascular aphasia patients and 14 control subjects were studied using functional magnetic resonance imaging (fMRI). Each performed: (1) a word generation (WG) task alone, followed by (2) repeating WG after insertion of acupuncture needles (WGN) into SJ 8 (a language-implicated acupoint), followed by (3) repeating WGN reinforced by electrical stimulation (WGA) of SJ 8, and finally (4) electrical stimulation (ES) of SJ 8 alone. Significant activation was found in the opercular, triangular, or insula during the ES stimulation in patients when comparing each patient to 14 normal controls. For the WG task, significant activation was found in the inferior frontal gyrus when comparing each patient to 14 normal controls. The signal induced by acupuncture was larger than that of the WG task in the left middle frontal gyrus with the comparison of WGA vs. WGN in seven patients. Further, main significant effects in the right insula in patients were observed when comparing seven patients to 14 normal controls. The activation induced by ES stimulation was only found on the left side in controls. This activation was observed on the lesion side of superior and middle frontal gyrus (SMFG) in patients. This study demonstrates for the first time that language-deficit-implicated acupoint stimulation can selectively activate the brain on the lesion side in post-stroke aphasia patients. These results suggest that acupuncture may have therapeutic benefits in post-stroke aphasia patients. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Ischemic conditioning-induced endogenous brain protection: Applications pre-, per- or post-stroke.

    Science.gov (United States)

    Wang, Yuechun; Reis, Cesar; Applegate, Richard; Stier, Gary; Martin, Robert; Zhang, John H

    2015-10-01

    In the area of brain injury and neurodegenerative diseases, a plethora of experimental and clinical evidence strongly indicates the promise of therapeutically exploiting the endogenous adaptive system at various levels like triggers, mediators and the end-effectors to stimulate and mobilize intrinsic protective capacities against brain injuries. It is believed that ischemic pre-conditioning and post-conditioning are actually the strongest known interventions to stimulate the innate neuroprotective mechanism to prevent or reverse neurodegenerative diseases including stroke and traumatic brain injury. Recently, studies showed the effectiveness of ischemic per-conditioning in some organs. Therefore the term ischemic conditioning, including all interventions applied pre-, per- and post-ischemia, which spans therapeutic windows in 3 time periods, has recently been broadly accepted by scientific communities. In addition, it is extensively acknowledged that ischemia-mediated protection not only affects the neurons but also all the components of the neurovascular network (consisting of neurons, glial cells, vascular endothelial cells, pericytes, smooth muscle cells, and venule/veins). The concept of cerebroprotection has been widely used in place of neuroprotection. Intensive studies on the cellular signaling pathways involved in ischemic conditioning have improved the mechanistic understanding of tolerance to cerebral ischemia. This has added impetus to exploration for potential pharmacologic mimetics, which could possibly induce and maximize inherent protective capacities. However, most of these studies were performed in rodents, and the efficacy of these mimetics remains to be evaluated in human patients. Several classical signaling pathways involving apoptosis, inflammation, or oxidation have been elaborated in the past decades. Newly characterized mechanisms are emerging with the advances in biotechnology and conceptual renewal. In this review we are going to focus on

  7. Tetrahydrocannabinol Induces Brain Mitochondrial Respiratory Chain Dysfunction and Increases Oxidative Stress: A Potential Mechanism Involved in Cannabis-Related Stroke

    Directory of Open Access Journals (Sweden)

    Valérie Wolff

    2015-01-01

    Full Text Available Cannabis has potential therapeutic use but tetrahydrocannabinol (THC, its main psychoactive component, appears as a risk factor for ischemic stroke in young adults. We therefore evaluate the effects of THC on brain mitochondrial function and oxidative stress, key factors involved in stroke. Maximal oxidative capacities Vmax (complexes I, III, and IV activities, Vsucc (complexes II, III, and IV activities, Vtmpd (complex IV activity, together with mitochondrial coupling (Vmax/V0, were determined in control conditions and after exposure to THC in isolated mitochondria extracted from rat brain, using differential centrifugations. Oxidative stress was also assessed through hydrogen peroxide (H2O2 production, measured with Amplex Red. THC significantly decreased Vmax (−71%; P<0.0001, Vsucc (−65%; P<0.0001, and Vtmpd (−3.5%; P<0.001. Mitochondrial coupling (Vmax/V0 was also significantly decreased after THC exposure (1.8±0.2 versus 6.3±0.7; P<0.001. Furthermore, THC significantly enhanced H2O2 production by cerebral mitochondria (+171%; P<0.05 and mitochondrial free radical leak was increased from 0.01±0.01 to 0.10±0.01% (P<0.001. Thus, THC increases oxidative stress and induces cerebral mitochondrial dysfunction. This mechanism may be involved in young cannabis users who develop ischemic stroke since THC might increase patient’s vulnerability to stroke.

  8. Brain-Heart Interaction: Cardiac Complications After Stroke.

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    Chen, Zhili; Venkat, Poornima; Seyfried, Don; Chopp, Michael; Yan, Tao; Chen, Jieli

    2017-08-04

    Neurocardiology is an emerging specialty that addresses the interaction between the brain and the heart, that is, the effects of cardiac injury on the brain and the effects of brain injury on the heart. This review article focuses on cardiac dysfunction in the setting of stroke such as ischemic stroke, brain hemorrhage, and subarachnoid hemorrhage. The majority of post-stroke deaths are attributed to neurological damage, and cardiovascular complications are the second leading cause of post-stroke mortality. Accumulating clinical and experimental evidence suggests a causal relationship between brain damage and heart dysfunction. Thus, it is important to determine whether cardiac dysfunction is triggered by stroke, is an unrelated complication, or is the underlying cause of stroke. Stroke-induced cardiac damage may lead to fatality or potentially lifelong cardiac problems (such as heart failure), or to mild and recoverable damage such as neurogenic stress cardiomyopathy and Takotsubo cardiomyopathy. The role of location and lateralization of brain lesions after stroke in brain-heart interaction; clinical biomarkers and manifestations of cardiac complications; and underlying mechanisms of brain-heart interaction after stroke, such as the hypothalamic-pituitary-adrenal axis; catecholamine surge; sympathetic and parasympathetic regulation; microvesicles; microRNAs; gut microbiome, immunoresponse, and systemic inflammation, are discussed. © 2017 American Heart Association, Inc.

  9. Macrophage-derived osteopontin induces reactive astrocyte polarization and promotes re-establishment of the blood brain barrier after ischemic stroke.

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    Gliem, Michael; Krammes, Kristina; Liaw, Lucy; van Rooijen, Nico; Hartung, Hans-Peter; Jander, Sebastian

    2015-12-01

    Infarcted regions of the brain after stroke are segregated from the intact brain by scar tissue comprising both fibrous and glial components. The extent and quality of scarring is influenced by inflammation. The matricellular glycoprotein osteopontin (OPN) is strongly induced in myeloid cells after stroke and may contribute to repair of ischemic brain lesions. To elucidate the role of OPN in scar formation, we induced photothrombotic brain infarction, characterized by circumscribed cortical infarctions with a well-defined border zone toward the intact brain parenchyma. The cellular source and functional role of OPN was addressed by studies in OPN null (OPN(-/-) ) mice, wild-type mice depleted of hematogenous monocytes/macrophages by clodronate-filled liposome treatment, and CCR2(-/-) bone marrow chimeric mice characterized by impaired hematogenous macrophage influx into the infarctions. OPN was mainly produced by hematogenous macrophages infiltrating into the inner border zone of the infarcts whereas astrocyte activation occurred in the outer border zone. In OPN(-/-) as well as macrophage-depleted mice, reactive astrocytes failed to properly extend processes from the periphery toward the center of the infarctions. This was associated with incomplete coverage of neovessels by astrocytic endfeet and persistent leakiness of the damaged blood brain barrier. In conclusion, OPN produced by hematogenous macrophages induces astrocyte process extension toward the infarct border zone, which may contribute to repair of the ischemic neurovascular unit. © 2015 Wiley Periodicals, Inc.

  10. BRAIN NEURON REGENERATION IN POST-STROKE REHABILITATION TREATMENT USING GRAPE PEEL AND SEED EXTRACT (Vitis vinifera) IN INDUCING ERK1 / 2 PATHWAY

    OpenAIRE

    Zanella Yolanda Lie; Meliantha Tandiono; Lucy Pricillia; Astrid Nandikasari Lukito; Cakra Parindra Gasmara

    2016-01-01

    Background and aims. Ischemic stroke can cause hypoxia in brain tissue and damage the neuron. The defense ability and plasticity is activated by ERK1/2 pathway. Grape peel and seed extract (Vitis vinifera can induce release neurotrophic factor that contribute in ERK1/2 pathway mechanism. This research aiming to prove that grape peel and seed extract can regenerate neuron in anatomical and functional view. Method. This research use true experimental design with sample in this research is 20...

  11. Autoimmune Responses to Brain Following Stroke

    OpenAIRE

    Becker, Kyra

    2012-01-01

    This review provides a synthesis of the work done by our laboratory that demonstrates the presence of cellular immune responses directed towards brain antigens in animals following experimental stroke as well as in patients following ischemic stroke. These responses include both antigenspecific Th1(+) responses, which are associated with worse stroke outcome, and antigen-specific Treg responses, which are associated with better stroke outcome. The likelihood of developing a detrimental Th1(+)...

  12. Prevention of rt-PA induced blood-brain barrier component degradation by the poly(ADP-ribose)polymerase inhibitor PJ34 after ischemic stroke in mice.

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    Teng, Fei; Beray-Berthat, Virginie; Coqueran, Bérard; Lesbats, Clémentine; Kuntz, Mélanie; Palmier, Bruno; Garraud, Marie; Bedfert, Cyrielle; Slane, Niamh; Bérézowski, Vincent; Szeremeta, Frédéric; Hachani, Johan; Scherman, Daniel; Plotkine, Michel; Doan, Bich-Thuy; Marchand-Leroux, Catherine; Margaill, Isabelle

    2013-10-01

    Recombinant tissue plasminogen activator (rt-PA) is the only pharmacological treatment approved for thrombolysis in patients suffering from ischemic stroke, but its administration aggravates the risk of hemorrhagic transformations. Experimental data demonstrated that rt-PA increases the activity of poly(ADP-ribose)polymerase (PARP). The aim of the present study was to investigate whether PJ34, a potent (PARP) inhibitor, protects the blood-brain barrier components from rt-PA toxicity. In our mouse model of cerebral ischemia, administration of rt-PA (10 mg/kg, i.v.) 6h after ischemia aggravated the post-ischemic degradation of ZO-1, claudin-5 and VE-cadherin, increased the hemorrhagic transformations (assessed by brain hemoglobin content and magnetic resonance imaging). Furthermore, rt-PA also aggravated ischemia-induced functional deficits. Combining PJ34 with rt-PA preserved the expression of ZO-1, claudin-5 and VE-cadherin, reduced the hemorrhagic transformations and improved the sensorimotor performances. In vitro studies also demonstrated that PJ34 crosses the blood-brain barrier and may thus exert its protective effect by acting on endothelial and/or parenchymal cells. Thus, co-treatment with a PARP inhibitor seems to be a promising strategy to reduce rt-PA-induced vascular toxicity after stroke. © 2013.

  13. Training the brain to survive stroke.

    Directory of Open Access Journals (Sweden)

    Jeff F Dunn

    Full Text Available Presently, little can be done to repair brain tissue after stroke damage. We hypothesized that the mammalian brain has an intrinsic capacity to adapt to low oxygen which would improve outcome from a reversible hypoxic/ischemic episode. Acclimation to chronic hypoxia causes increased capillarity and tissue oxygen levels which may improve the capacity to survive ischemia. Identification of these adaptations will lead to protocols which high risk groups could use to improve recovery and reduce costs.Rats were exposed to hypoxia (3 weeks living at ½ an atmosphere. After acclimation, capillary density was measured morphometrically and was increased by 30% in the cortex. Novel implantable oxygen sensors showed that partial pressure of oxygen in the brain was increased by 40% in the normal cortex. Infarcts were induced in brain with 1 h reversible middle cerebral artery occlusions. After ischemia (48 h behavioural scores were improved and T2 weighted MRI lesion volumes were reduced by 52% in acclimated groups. There was a reduction in inflammation indicated by reduced lymphocytes (by 27-33%, and ED1 positive cells (by 35-45%.It is possible to stimulate a natural adaptive mechanism in the brain which will reduce damage and improve outcome for a given ischemic event. Since these adaptations occur after factors such as HIF-1α have returned to baseline, protection is likely related more to morphological changes such as angiogenesis. Such pre-conditioning, perhaps with exercise or pharmaceuticals, would not necessarily reduce the incidence of stroke, but the severity of damage could be reduced by 50%.

  14. Biosensors for brain trauma and dual laser doppler flowmetry: enoxaparin simultaneously reduces stroke-induced dopamine and blood flow while enhancing serotonin and blood flow in motor neurons of brain, in vivo.

    Science.gov (United States)

    Broderick, Patricia A; Kolodny, Edwin H

    2011-01-01

    Neuromolecular Imaging (NMI) based on adsorptive electrochemistry, combined with Dual Laser Doppler Flowmetry (LDF) is presented herein to investigate the brain neurochemistry affected by enoxaparin (Lovenox(®)), an antiplatelet/antithrombotic medication for stroke victims. NMI with miniature biosensors enables neurotransmitter and neuropeptide (NT) imaging; each NT is imaged with a response time in milliseconds. A semiderivative electronic reduction circuit images several NT's selectively and separately within a response time of minutes. Spatial resolution of NMI biosensors is in the range of nanomicrons and electrochemically-induced current ranges are in pico- and nano-amperes. Simultaneously with NMI, the LDF technology presented herein operates on line by illuminating the living brain, in this example, in dorso-striatal neuroanatomic substrates via a laser sensor with low power laser light containing optical fiber light guides. NMI biotechnology with BRODERICK PROBE(®) biosensors has a distinct advantage over conventional electrochemical methodologies both in novelty of biosensor formulations and on-line imaging capabilities in the biosensor field. NMI with unique biocompatible biosensors precisely images NT in the body, blood and brain of animals and humans using characteristic experimentally derived half-wave potentials driven by oxidative electron transfer. Enoxaparin is a first line clinical treatment prescribed to halt the progression of acute ischemic stroke (AIS). In the present studies, BRODERICK PROBE(®) laurate biosensors and LDF laser sensors are placed in dorsal striatum (DStr) dopaminergic motor neurons in basal ganglia of brain in living animals; basal ganglia influence movement disorders such as those correlated with AIS. The purpose of these studies is to understand what is happening in brain neurochemistry and cerebral blood perfusion after causal AIS by middle cerebral artery occlusion in vivo as well as to understand consequent enoxaparin

  15. Biosensors for Brain Trauma and Dual Laser Doppler Flowmetry: Enoxaparin Simultaneously Reduces Stroke-Induced Dopamine and Blood Flow while Enhancing Serotonin and Blood Flow in Motor Neurons of Brain, In Vivo

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    Edwin H. Kolodny

    2010-12-01

    Full Text Available Neuromolecular Imaging (NMI based on adsorptive electrochemistry, combined with Dual Laser Doppler Flowmetry (LDF is presented herein to investigate the brain neurochemistry affected by enoxaparin (Lovenox®, an antiplatelet/antithrombotic medication for stroke victims. NMI with miniature biosensors enables neurotransmitter and neuropeptide (NT imaging; each NT is imaged with a response time in milliseconds. A semiderivative electronic reduction circuit images several NT’s selectively and separately within a response time of minutes. Spatial resolution of NMI biosensors is in the range of nanomicrons and electrochemically-induced current ranges are in pico- and nano-amperes. Simultaneously with NMI, the LDF technology presented herein operates on line by illuminating the living brain, in this example, in dorso-striatal neuroanatomic substrates via a laser sensor with low power laser light containing optical fiber light guides. NMI biotechnology with BRODERICK PROBE® biosensors has a distinct advantage over conventional electrochemical methodologies both in novelty of biosensor formulations and on-line imaging capabilities in the biosensor field. NMI with unique biocompatible biosensors precisely images NT in the body, blood and brain of animals and humans using characteristic experimentally derived half-wave potentials driven by oxidative electron transfer. Enoxaparin is a first line clinical treatment prescribed to halt the progression of acute ischemic stroke (AIS. In the present studies, BRODERICK PROBE® laurate biosensors and LDF laser sensors are placed in dorsal striatum (DStr dopaminergic motor neurons in basal ganglia of brain in living animals; basal ganglia influence movement disorders such as those correlated with AIS. The purpose of these studies is to understand what is happening in brain neurochemistry and cerebral blood perfusion after causal AIS by middle cerebral artery occlusion in vivo as well as to understand consequent

  16. BRAIN NEURON REGENERATION IN POST-STROKE REHABILITATION TREATMENT USING GRAPE PEEL AND SEED EXTRACT (Vitis vinifera IN INDUCING ERK1 / 2 PATHWAY

    Directory of Open Access Journals (Sweden)

    Zanella Yolanda Lie

    2016-01-01

    Full Text Available Background and aims. Ischemic stroke can cause hypoxia in brain tissue and damage the neuron. The defense ability and plasticity is activated by ERK1/2 pathway. Grape peel and seed extract (Vitis vinifera can induce release neurotrophic factor that contribute in ERK1/2 pathway mechanism. This research aiming to prove that grape peel and seed extract can regenerate neuron in anatomical and functional view. Method. This research use true experimental design with sample in this research is 20 male 8-10 weeks old wistar strain rats which are induced stroke by internal and external carotid artery occlusion method. There are five groups in this research, negative control, positive control, grape peel and seed extract 50mg/KgBW, 100mg/KgBW, and 200mg/KgBW. After reassurement that rat suffer from stroke with MMP9, cylinder test and ladder rung walking test, rats are given grape peel and seed extract in variable dose to know how extract’s effect in neuron repairment. Results. The repairment is monitored from four parameters, namely cylinder test score, ladder rung walking test score, extensive infarct volume, and number of damaged neuron. Conclusion. The result is 50mg/KgBW is effective in repairing neuron. It is seen from the result of improvement in four parameters explained above.

  17. Structural changes induced by daily music listening in the recovering brain after middle cerebral artery stroke: a voxel-based morphometry study.

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    Särkämö, Teppo; Ripollés, Pablo; Vepsäläinen, Henna; Autti, Taina; Silvennoinen, Heli M; Salli, Eero; Laitinen, Sari; Forsblom, Anita; Soinila, Seppo; Rodríguez-Fornells, Antoni

    2014-01-01

    Music is a highly complex and versatile stimulus for the brain that engages many temporal, frontal, parietal, cerebellar, and subcortical areas involved in auditory, cognitive, emotional, and motor processing. Regular musical activities have been shown to effectively enhance the structure and function of many brain areas, making music a potential tool also in neurological rehabilitation. In our previous randomized controlled study, we found that listening to music on a daily basis can improve cognitive recovery and improve mood after an acute middle cerebral artery stroke. Extending this study, a voxel-based morphometry (VBM) analysis utilizing cost function masking was performed on the acute and 6-month post-stroke stage structural magnetic resonance imaging data of the patients (n = 49) who either listened to their favorite music [music group (MG), n = 16] or verbal material [audio book group (ABG), n = 18] or did not receive any listening material [control group (CG), n = 15] during the 6-month recovery period. Although all groups showed significant gray matter volume (GMV) increases from the acute to the 6-month stage, there was a specific network of frontal areas [left and right superior frontal gyrus (SFG), right medial SFG] and limbic areas [left ventral/subgenual anterior cingulate cortex (SACC) and right ventral striatum (VS)] in patients with left hemisphere damage in which the GMV increases were larger in the MG than in the ABG and in the CG. Moreover, the GM reorganization in the frontal areas correlated with enhanced recovery of verbal memory, focused attention, and language skills, whereas the GM reorganization in the SACC correlated with reduced negative mood. This study adds on previous results, showing that music listening after stroke not only enhances behavioral recovery, but also induces fine-grained neuroanatomical changes in the recovering brain.

  18. Structural changes induced by daily music listening in the recovering brain after middle cerebral artery stroke: a voxel-based morphometry study

    Directory of Open Access Journals (Sweden)

    Teppo eSärkämö

    2014-04-01

    Full Text Available Music is a highly complex and versatile stimulus for the brain that engages many temporal, frontal, parietal, cerebellar, and subcortical areas involved in auditory, cognitive, emotional, and motor processing. Regular musical activities have been shown to effectively enhance the structure and function of many brain areas, making music a potential tool also in neurological rehabilitation. In our previous randomized controlled study, we found that listening to music on a daily basis can improve cognitive recovery and improve mood after an acute middle cerebral artery (MCA stroke. Extending this study, a voxel-based morphometry (VBM analysis utilizing cost-function masking was performed on the acute and 6-month post-stroke stage structural MRI data of the patients (n = 49 who either listened to their favourite music (music group, n = 16 or verbal material (audio book group, n = 18 or did not receive any listening material (control group, n = 15 during the 6-month recovery period. Although all groups showed significant grey matter volume (GMV increases from the acute to the 6-month stage, there was a specific network of frontal areas [left and right superior frontal gyrus (SFG, right medial SFG] and limbic areas [left ventral / subgenual anterior cingulate cortex (SACC and right ventral striatum (VS] in patients with left hemisphere damage in which the GMV increases were larger in the music group than in the audio book and control groups. Moreover, the GM reorganization in the frontal areas correlated with enhanced recovery of verbal memory, focused attention, and language skills, whereas the GM reorganization in the SACC correlated with reduced negative mood. This study adds on previous results, showing that music listening after stroke not only enhances behavioural recovery, but also induces fine-grained neuroanatomical changes in the recovering brain.

  19. Bilateral brain reorganization with memantine and constraint-induced aphasia therapy in chronic post-stroke aphasia: An ERP study.

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    Barbancho, Miguel A; Berthier, Marcelo L; Navas-Sánchez, Patricia; Dávila, Guadalupe; Green-Heredia, Cristina; García-Alberca, José M; Ruiz-Cruces, Rafael; López-González, Manuel V; Dawid-Milner, Marc S; Pulvermüller, Friedemann; Lara, J Pablo

    2015-01-01

    Changes in ERP (P100 and N400) and root mean square (RMS) were obtained during a silent reading task in 28 patients with chronic post-stroke aphasia in a randomized, double-blind, placebo-controlled trial of both memantine and constraint-induced aphasia therapy (CIAT). Participants received memantine/placebo alone (weeks 0-16), followed by drug treatment combined with CIAT (weeks 16-18), and then memantine/placebo alone (weeks 18-20). ERP/RMS values (week 16) decreased more in the memantine group than in the placebo group. During CIAT application (weeks 16-18), improvements in aphasia severity and ERP/RMS values were amplified by memantine and changes remained stable thereafter (weeks 18-20). Changes in ERP/RMS occurred in left and right hemispheres and correlated with gains in language performance. No changes in ERP/RMS were found in a healthy group in two separated evaluations. Our results show that aphasia recovery induced by both memantine alone and in combination with CIAT is indexed by bilateral cortical potentials. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. A functional MRI study of the brain in stroke patients with upper-limb paralysis treated with constraint-induced movement therapy

    International Nuclear Information System (INIS)

    Wen Bo; Ma Lin; Weng Changshui; Zheng Zhixin; Sun Tong

    2009-01-01

    Objective: To investigate and compare the activation patterns of stroke patients with upper-limb paralysis using functional MRI before and after treatment with constraint-induced movement therapy (CIMT) so as to explore the mechanism of CIMT. Methods: Six patients in chronic stage of brain infarction who have functional disturbance in right upper-limb and 9 normal controls were entered into the study. All of the patients were asked to perform the thumb-to-index finger tapping task and underwent functional MRI before and two weeks after CIMT. The controls underwent fMRI of same protocol once. The patients' upper-limb function scores before and after CIMT were analyzed with SPSS 11.5 by paired t test. The fMRI data were analyzed with analysis of functional neurolmages (AFNI) software. The percentage of blood oxygenation level dependent (BOLD) signal change for the normal control was analyzed by one-sample t test to indentify the activated brain regions. The percentage change of BOLD signal for the patients before and after CIMT was compared to control's data by independent-samples t test. The percentage change of BOLD signal for the patients before and after CIMT was analyzed by paired-samples t test. The significant difference level was set P<0.05. Results: The fMRI showed the patients' activated brain regions before CIMT were similar to that of the controls', while the activation level was lower. There were wide areas activated to compensate the impaired function especially for the fight upper-limb. Before CIMT, the patients' score for fight upper-limb on the action research arm test was 27±4. After CIMT, the patients' score was 40±3, and the difference was significant (t=14.626, P<0.05), which indicated the improved function. These subjects also displayed cortical reorganization after CIMT on fMRI. The areas responsible for the right hand movement showed increased activation and the activation level at bilateral corpora striata thalami, and cerebella increased

  1. Investigations into Brain-Computer Interfacing for Stroke Rehabilitation

    OpenAIRE

    Leamy, Darren J.

    2015-01-01

    A stroke is the loss of brain function following the cessation of blood supply to a region of the brain caused by either a blockage or haemorrhage in the vasculature. It is a leading cause of death worldwide but survival rates have increased significantly in the past 25 years with recent estimates putting the number of worldwide stroke survivors at 33 million. Stroke survivors live with lasting effects such as limb weakness, limb paralysis, loss of speech, loss of comprehens...

  2. Brain repair: cell therapy in stroke

    Directory of Open Access Journals (Sweden)

    Kalladka D

    2014-02-01

    Full Text Available Dheeraj Kalladka, Keith W Muir Institute of Neuroscience and Psychology, University of Glasgow, Southern General Hospital, Glasgow, United Kingdom Abstract: Stroke affects one in every six people worldwide, and is the leading cause of adult disability. Some spontaneous recovery is usual but of limited extent, and the mechanisms of late recovery are not completely understood. Endogenous neurogenesis in humans is thought to contribute to repair, but its extent is unknown. Exogenous cell therapy is promising as a means of augmenting brain repair, with evidence in animal stroke models of cell migration, survival, and differentiation, enhanced endogenous angiogenesis and neurogenesis, immunomodulation, and the secretion of trophic factors by stem cells from a variety of sources, but the potential mechanisms of action are incompletely understood. In the animal models of stroke, both mesenchymal stem cells (MSCs and neural stem cells (NSCs improve functional recovery, and MSCs reduce the infarct volume when administered acutely, but the heterogeneity in the choice of assessment scales, publication bias, and the possible confounding effects of immunosuppressants make the comparison of effects across cell types difficult. The use of adult-derived cells avoids the ethical issues around embryonic cells but may have more restricted differentiation potential. The use of autologous cells avoids rejection risk, but the sources are restricted, and culture expansion may be necessary, delaying treatment. Allogeneic cells offer controlled cell numbers and immediate availability, which may have advantages for acute treatment. Early clinical trials of both NSCs and MSCs are ongoing, and clinical safety data are emerging from limited numbers of selected patients. Ongoing research to identify prognostic imaging markers may help to improve patient selection, and the novel imaging techniques may identify biomarkers of recovery and the mechanism of action for cell

  3. Drug-induced Hypothermia by 5HT1A Agonists Provide Neuroprotection in Experimental Stroke

    DEFF Research Database (Denmark)

    Johansen, Flemming Fryd; Hasseldam, Henrik; Nybro Smith, Matthias

    2014-01-01

    BACKGROUND: Drug-induced hypothermia reduces brain damage in animal stroke models and is an undiscovered potential in human stroke treatment. We studied hypothermia induced by the serotonergic agonists S14671 (1-[2-(2-thenoylamino)ethyl]-4[1-(7- methoxynaphtyl)]piperazine) and ipsapirone in a rat...

  4. Glutamate oxaloacetate transaminase enables anaplerotic refilling of TCA cycle intermediates in stroke-affected brain.

    Science.gov (United States)

    Rink, Cameron; Gnyawali, Surya; Stewart, Richard; Teplitsky, Seth; Harris, Hallie; Roy, Sashwati; Sen, Chandan K; Khanna, Savita

    2017-04-01

    Ischemic stroke results in excessive release of glutamate, which contributes to neuronal cell death. Here, we test the hypothesis that otherwise neurotoxic glutamate can be productively metabolized by glutamate oxaloacetate transaminase (GOT) to maintain cellular energetics and protect the brain from ischemic stroke injury. The GOT-dependent metabolism of glutamate was studied in primary neural cells and in stroke-affected C57-BL6 mice using magnetic resonance spectroscopy and GC-MS. Extracellular Glu sustained cell viability under hypoglycemic conditions and increased GOT-mediated metabolism in vitro Correction of stroke-induced hypoxia using supplemental oxygen in vivo lowered Glu levels as measured by 1 H magnetic resonance spectroscopy. GOT knockdown abrogated this effect and caused ATP loss in the stroke-affected brain. GOT overexpression increased anaplerotic refilling of tricarboxylic acid cycle intermediates in mouse brain during ischemic stroke. Furthermore, GOT overexpression not only reduced ischemic stroke lesion volume but also attenuated neurodegeneration and improved poststroke sensorimotor function. Taken together, our results support a new paradigm that GOT enables metabolism of otherwise neurotoxic extracellular Glu through a truncated tricarboxylic acid cycle under hypoglycemic conditions.-Rink, C., Gnyawali, S., Stewart, R., Teplitsky, S., Harris, H., Roy, S., Sen, C. K., Khanna, S. Glutamate oxaloacetate transaminase enables anaplerotic refilling of TCA cycle intermediates in stroke-affected brain. © FASEB.

  5. Inflammatory Stroke Extracellular Vesicles Induce Macrophage Activation.

    Science.gov (United States)

    Couch, Yvonne; Akbar, Naveed; Davis, Simon; Fischer, Roman; Dickens, Alex M; Neuhaus, Ain A; Burgess, Annette I; Rothwell, Peter M; Buchan, Alastair M

    2017-08-01

    Extracellular vesicles (EVs) are protein-lipid complexes released from cells, as well as actively exocytosed, as part of normal physiology, but also during pathological processes such as those occurring during a stroke. Our aim was to determine the inflammatory potential of stroke EVs. EVs were quantified and analyzed in the sera of patients after an acute stroke (size, is significantly increased in stroke patients when compared to age-matched controls. Proteomic analysis reveals an overall increase in acute phase proteins, including C-reactive protein. EV fractions applied to monocyte-differentiated macrophage cultures induced inflammatory gene expression. Together these data show that EVs from stroke patients are proinflammatory in nature and are capable of inducing inflammation in immune cells. © 2017 American Heart Association, Inc.

  6. Brain Function and Upper Limb Outcome in Stroke: A Cross-Sectional fMRI Study.

    Science.gov (United States)

    Buma, Floor E; Raemaekers, Mathijs; Kwakkel, Gert; Ramsey, Nick F

    2015-01-01

    The nature of changes in brain activation related to good recovery of arm function after stroke is still unclear. While the notion that this is a reflection of neuronal plasticity has gained much support, confounding by compensatory strategies cannot be ruled out. We address this issue by comparing brain activity in recovered patients 6 months after stroke with healthy controls. We included 20 patients with upper limb paresis due to ischemic stroke and 15 controls. We measured brain activation during a finger flexion-extension task with functional MRI, and the relationship between brain activation and hand function. Patients exhibited various levels of recovery, but all were able to perform the task. Comparison between patients and controls with voxel-wise whole-brain analysis failed to reveal significant differences in brain activation. Equally, a region of interest analysis constrained to the motor network to optimize statistical power, failed to yield any differences. Finally, no significant relationship between brain activation and hand function was found in patients. Patients and controls performed scanner task equally well. Brain activation and behavioral performance during finger flexion-extensions in (moderately) well recovered patients seems normal. The absence of significant differences in brain activity even in patients with a residual impairment may suggest that infarcts do not necessarily induce reorganization of motor function. While brain activity could be abnormal with higher task demands, this may also introduce performance confounds. It is thus still uncertain to what extent capacity for true neuronal repair after stroke exists.

  7. Structural MRI markers of brain aging early after ischemic stroke.

    Science.gov (United States)

    Werden, Emilio; Cumming, Toby; Li, Qi; Bird, Laura; Veldsman, Michele; Pardoe, Heath R; Jackson, Graeme; Donnan, Geoffrey A; Brodtmann, Amy

    2017-07-11

    To examine associations between ischemic stroke, vascular risk factors, and MRI markers of brain aging. Eighty-one patients (mean age 67.5 ± 13.1 years, 31 left-sided, 61 men) with confirmed first-ever (n = 66) or recurrent (n = 15) ischemic stroke underwent 3T MRI scanning within 6 weeks of symptom onset (mean 26 ± 9 days). Age-matched controls (n = 40) completed identical testing. Multivariate regression analyses examined associations between group membership and MRI markers of brain aging (cortical thickness, total brain volume, white matter hyperintensity [WMH] volume, hippocampal volume), normalized against intracranial volume, and the effects of vascular risk factors on these relationships. First-ever stroke was associated with smaller hippocampal volume ( p = 0.025) and greater WMH volume ( p = 0.004) relative to controls. Recurrent stroke was in turn associated with smaller hippocampal volume relative to both first-ever stroke ( p = 0.017) and controls ( p = 0.001). These associations remained significant after adjustment for age, sex, education, and, in stroke patients, infarct volume. Total brain volume was not significantly smaller in first-ever stroke patients than in controls ( p = 0.056), but the association became significant after further adjustment for atrial fibrillation ( p = 0.036). Cortical thickness and brain volumes did not differ as a function of stroke type, infarct volume, or etiology. Brain structure is likely to be compromised before ischemic stroke by vascular risk factors. Smaller hippocampal and total brain volumes and increased WMH load represent proxies for underlying vascular brain injury. Copyright © 2017 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.

  8. Severe Blood–Brain Barrier Disruption in Cardioembolic Stroke

    OpenAIRE

    Chang Liu; Feina Shi; Zhicai Chen; Shenqiang Yan; Xinfa Ding; Min Lou

    2018-01-01

    BackgroundPrevious studies demonstrated that cardioembolism (CE) was prone to develop hemorrhagic transformation (HT), whereas hyper-permeability of blood–brain barrier (BBB) might be one reason for the development of HT. We, thus, aimed to investigate whether the BBB permeability (BBBP) was higher in CE stroke than other stroke subtypes in acute ischemic stroke (AIS) patients.MethodsThis study was a retrospective review of prospectively collected clinical and imaging database of AIS patients...

  9. Brain repair after stroke--a novel neurological model.

    Science.gov (United States)

    Small, Steven L; Buccino, Giovanni; Solodkin, Ana

    2013-12-01

    Following stroke, patients are commonly left with debilitating motor and speech impairments. This article reviews the state of the art in neurological repair for stroke and proposes a new model for the future. We suggest that stroke treatment--from the time of the ictus itself to living with the consequences--must be fundamentally neurological, from limiting the extent of injury at the outset, to repairing the consequent damage. Our model links brain and behaviour by targeting brain circuits, and we illustrate the model though action observation treatment, which aims to enhance brain network connectivity. The model is based on the assumptions that the mechanisms of neural repair inherently involve cellular and circuit plasticity, that brain plasticity is a synaptic phenomenon that is largely stimulus-dependent, and that brain repair required both physical and behavioural interventions that are tailored to reorganize specific brain circuits. We review current approaches to brain repair after stroke and present our new model, and discuss the biological foundations, rationales, and data to support our novel approach to upper-extremity and language rehabilitation. We believe that by enhancing plasticity at the level of brain network interactions, this neurological model for brain repair could ultimately lead to a cure for stroke.

  10. Deep brain stimulation for stroke: Current uses and future directions.

    Science.gov (United States)

    Elias, Gavin J B; Namasivayam, Andrew A; Lozano, Andres M

    Survivors of stroke often experience significant disability and impaired quality of life related to ongoing maladaptive responses and persistent neurologic deficits. Novel therapeutic options are urgently needed to augment current approaches. One way to promote recovery and ameliorate symptoms may be to electrically stimulate the surviving brain. Various forms of brain stimulation have been investigated for use in stroke, including deep brain stimulation (DBS). We conducted a comprehensive literature review in order to 1) review the use of DBS to treat post-stroke maladaptive responses including pain, dystonia, dyskinesias, and tremor and 2) assess the use and potential utility of DBS for enhancing plasticity and recovery from post-stroke neurologic deficits. A large variety of brain structures have been targeted in post-stroke patients, including motor thalamus, sensory thalamus, basal ganglia nuclei, internal capsule, and periventricular/periaqueductal grey. Overall, the reviewed clinical literature suggests a role for DBS in the management of several post-stroke maladaptive responses. More limited evidence was identified regarding DBS for post-stroke motor deficits, although existing work tentatively suggests DBS-particularly DBS targeting the posterior limb of the internal capsule-may improve paresis in certain circumstances. Substantial future work is required both to establish optimal targets and parameters for treatment of maladapative responses and to further investigate the effectiveness of DBS for post-stroke paresis. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Chromium supplementation improved post-stroke brain infarction and hyperglycemia.

    Science.gov (United States)

    Chen, Wen-Ying; Mao, Frank Chiahung; Liu, Chia-Hsin; Kuan, Yu-Hsiang; Lai, Nai-Wei; Wu, Chih-Cheng; Chen, Chun-Jung

    2016-04-01

    Hyperglycemia is common after acute stroke and is associated with a worse outcome of stroke. Thus, a better understanding of stress hyperglycemia is helpful to the prevention and therapeutic treatment of stroke. Chromium is an essential nutrient required for optimal insulin activity and normal carbohydrate and lipid metabolism. Beyond its nutritional effects, dietary supplement of chromium causes beneficial outcomes against several diseases, in particular diabetes-associated complications. In this study, we investigated whether post-stroke hyperglycemia involved chromium dynamic mobilization in a rat model of permanent focal cerebral ischemia and whether dietary supplement of chromium improved post-stroke injury and alterations. Stroke rats developed brain infarction, hyperglycemia, hyperinsulinemia, glucose intolerance, and insulin resistance. Post-stroke hyperglycemia was accompanied by elevated secretion of counter-regulatory hormones including glucagon, corticosterone, and norepinephrine, decreased insulin signaling in skeletal muscles, and increased hepatic gluconeogenesis. Correlation studies revealed that counter-regulatory hormone secretion showed a positive correlation with chromium loss and blood glucose increased together with chromium loss. Daily chromium supplementation increased tissue chromium levels, attenuated brain infarction, improved hyperglycemia, and decreased plasma levels of glucagon and corticosterone in stroke rats. Our findings suggest that stroke rats show disturbance of tissue chromium homeostasis with a net loss through urinary excretion and chromium mobilization and loss might be an alternative mechanism responsible for post-stroke hyperglycemia.

  12. Blood-brain barrier and cerebral blood flow: Age differences in hemorrhagic stroke

    Directory of Open Access Journals (Sweden)

    Semyachkina-Glushkovskaya Oxana

    2015-11-01

    Full Text Available Neonatal stroke is similar to the stroke that occurs in adults and produces a significant morbidity and long-term neurologic and cognitive deficits. There are important differences in the factors, clinical events and outcomes associated with the stroke in infants and adults. However, mechanisms underlying age differences in the stroke development remain largely unknown. Therefore, treatment guidelines for neonatal stroke must extrapolate from the adult data that is often not suitable for children. The new information about differences between neonatal and adult stroke is essential for identification of significant areas for future treatment and effective prevention of neonatal stroke. Here, we studied the development of stress-induced hemorrhagic stroke and possible mechanisms underlying these processes in newborn and adult rats. Using histological methods and magnetic resonance imaging, we found age differences in the type of intracranial hemorrhages. Newborn rats demonstrated small superficial bleedings in the cortex while adult rats had more severe deep bleedings in the cerebellum. Using Doppler optical coherent tomography, we found higher stress-reactivity of the sagittal sinus to deleterious effects of stress in newborn vs. adult rats suggesting that the cerebral veins are more vulnerable to negative stress factors in neonatal vs. adult brain in rats. However, adult but not newborn rats demonstrated the stroke-induced breakdown of blood brain barrier (BBB permeability. The one of possible mechanisms underlying the higher resistance to stress-related stroke injures of cerebral vessels in newborn rats compared with adult animals is the greater expression of two main tight junction proteins of BBB (occludin and claudin-5 in neonatal vs. mature brain in rats.

  13. The image of a brain stroke in a computed tomograph

    International Nuclear Information System (INIS)

    Just, E.G.

    1982-01-01

    On the basis of 100 findings from patients who suffered brain strokes and by the use of 1500 ensured stroke images it was tested whether or not the stroke-predilection typologie outlined by Zuelch is based on a coincidental summation of individual cases. The radio-computed tomography with the possibility of evaluation of non-lethal cases proved itself as a suited method for confirmation or repudiation of this stroke theory. By means of the consistently achieved association of the frontal, respectively horizontal sectional image for the typology it could be proven and - with the exception of a few rather seldom types - also demonstrated that the basic and predilection types of brain stroke repeated themselves in their pattern. In individual cases a specification of lower types could also be undertaken. (orig./TRV) [de

  14. Hydrogel-delivered brain-derived neurotrophic factor promotes tissue repair and recovery after stroke.

    Science.gov (United States)

    Cook, Douglas J; Nguyen, Cynthia; Chun, Hyun N; L Llorente, Irene; Chiu, Abraham S; Machnicki, Michal; Zarembinski, Thomas I; Carmichael, S Thomas

    2017-03-01

    Stroke is the leading cause of adult disability. Systemic delivery of candidate neural repair therapies is limited by the blood-brain barrier and off-target effects. We tested a bioengineering approach for local depot release of BDNF from the infarct cavity for neural repair in chronic periods after stroke. The brain release levels of a hyaluronic acid hydrogel + BDNF were tested in several stroke models in mouse (strains C57Bl/6, DBA) and non-human primate ( Macaca fascicularis) and tracked with MRI. The behavioral recovery effects of hydrogel + BDNF and the effects on tissue repair outcomes were determined. Hydrogel-delivered BDNF diffuses from the stroke cavity into peri-infarct tissue over 3 weeks in two mouse stroke models, compared with 1 week for direct BDNF injection. Hydrogel delivery of BDNF promotes recovery of motor function. Mapping of motor system connections indicates that hydrogel-BDNF induces axonal sprouting within existing cortical and cortico-striatal systems. Pharmacogenetic studies show that hydrogel-BDNF induces the initial migration of immature neurons into the peri-infarct cortex and their long-term survival. In chronic stroke in the non-human primate, hydrogel-released BDNF can be detected up to 2 cm from the infarct, a distance relevant to human functional recovery in stroke. The hydrogel can be tracked by MRI in mouse and primate.

  15. Brain-machine interfaces in neurorehabilitation of stroke.

    Science.gov (United States)

    Soekadar, Surjo R; Birbaumer, Niels; Slutzky, Marc W; Cohen, Leonardo G

    2015-11-01

    Stroke is among the leading causes of long-term disabilities leaving an increasing number of people with cognitive, affective and motor impairments depending on assistance in their daily life. While function after stroke can significantly improve in the first weeks and months, further recovery is often slow or non-existent in the more severe cases encompassing 30-50% of all stroke victims. The neurobiological mechanisms underlying recovery in those patients are incompletely understood. However, recent studies demonstrated the brain's remarkable capacity for functional and structural plasticity and recovery even in severe chronic stroke. As all established rehabilitation strategies require some remaining motor function, there is currently no standardized and accepted treatment for patients with complete chronic muscle paralysis. The development of brain-machine interfaces (BMIs) that translate brain activity into control signals of computers or external devices provides two new strategies to overcome stroke-related motor paralysis. First, BMIs can establish continuous high-dimensional brain-control of robotic devices or functional electric stimulation (FES) to assist in daily life activities (assistive BMI). Second, BMIs could facilitate neuroplasticity, thus enhancing motor learning and motor recovery (rehabilitative BMI). Advances in sensor technology, development of non-invasive and implantable wireless BMI-systems and their combination with brain stimulation, along with evidence for BMI systems' clinical efficacy suggest that BMI-related strategies will play an increasing role in neurorehabilitation of stroke. Copyright © 2014. Published by Elsevier Inc.

  16. Constraint-induced movement therapy and rehabilitation exercises lessen motor deficits and volume of brain injury after striatal hemorrhagic stroke in rats.

    Science.gov (United States)

    DeBow, Suzanne B; Davies, Melissa L A; Clarke, Heather L; Colbourne, Frederick

    2003-04-01

    Constraint-induced movement therapy (CIMT) promotes motor recovery after occlusive stroke in humans, but its efficacy after intracerebral hemorrhage (ICH) has not been investigated clinically or in the laboratory. In this study we tested whether CIMT and a rehabilitation exercise program would lessen motor deficits after ICH in rats. Rats were subjected to striatal ICH (via infusion of collagenase) or sham stroke. Seven days later, treatment began with CIMT (8 h/d of ipsilateral forelimb restraint), rehabilitation exercises (eg, reaching, walking; 1 h/d), or both for 7 days. Some rats were not treated. Motor deficits were assessed up to the 60-day survival time, after which the volume of tissue lost was determined. Untreated ICH rats made more limb slips traversing a horizontal ladder and showed an asymmetry toward less use of the contralateral paw in the cylinder test of limb use asymmetry (day 28). These rats were also significantly less successful in the Montoya staircase test (days 55 to 59) of skilled reaching. Neither therapy alone provided much benefit. However, the combination of daily exercises and CIMT substantially and persistently improved recovery. Unexpectedly, this group had a statistically smaller volume of tissue lost than untreated ICH rats. The combination of focused rehabilitation exercises and CIMT effectively promotes functional recovery after ICH, while either therapy alone is less effective. This therapy may work in part by reducing the volume of tissue lost, likely through reducing atrophy while promoting remodeling.

  17. Constraint-induced movement therapy after stroke

    NARCIS (Netherlands)

    Kwakkel, G.; Veerbeek, J.M.; van Wegen, E.E.H.; Wolf, S.L.

    2015-01-01

    Constraint-induced movement therapy (CIMT) was developed to overcome upper limb impairments after stroke and is the most investigated intervention for the rehabilitation of patients. Original CIMT includes constraining of the non-paretic arm and task-oriented training. Modified versions also apply

  18. Multisensory stimulation improves functional recovery and resting-state functional connectivity in the mouse brain after stroke

    Directory of Open Access Journals (Sweden)

    Jakob Hakon

    2018-01-01

    Full Text Available Stroke causes direct structural damage to local brain networks and indirect functional damage to distant brain regions. Neuroplasticity after stroke involves molecular changes within perilesional tissue that can be influenced by regions functionally connected to the site of injury. Spontaneous functional recovery can be enhanced by rehabilitative strategies, which provides experience-driven cell signaling in the brain that enhances plasticity. Functional neuroimaging in humans and rodents has shown that spontaneous recovery of sensorimotor function after stroke is associated with changes in resting-state functional connectivity (RS-FC within and across brain networks. At the molecular level, GABAergic inhibitory interneurons can modulate brain plasticity in peri-infarct and remote brain regions. Among this cell-type, a decrease in parvalbumin (PV-immunoreactivity has been associated with improved behavioral outcome. Subjecting rodents to multisensory stimulation through exposure to an enriched environment (EE enhances brain plasticity and recovery of function after stroke. Yet, how multisensory stimulation relates to RS-FC has not been determined. In this study, we investigated the effect of EE on recovery of RS-FC and behavior in mice after stroke, and if EE-related changes in RS-FC were associated with levels of PV-expressing neurons. Photothrombotic stroke was induced in the sensorimotor cortex. Beginning 2 days after stroke, mice were housed in either standard environment (STD or EE for 12 days. Housing in EE significantly improved lost tactile-proprioceptive function compared to mice housed in STD environment. RS-FC in the mouse was measured by optical intrinsic signal imaging 14 days after stroke or sham surgery. Stroke induced a marked reduction in RS-FC within several perilesional and remote brain regions. EE partially restored interhemispheric homotopic RS-FC between spared motor regions, particularly posterior secondary motor

  19. Exacerbation of Brain Injury by Post-Stroke Exercise Is Contingent Upon Exercise Initiation Timing

    Directory of Open Access Journals (Sweden)

    Fengwu Li

    2017-10-01

    Full Text Available Accumulating evidence has demonstrated that post-stroke physical rehabilitation may reduce morbidity. The effectiveness of post-stroke exercise, however, appears to be contingent upon exercise initiation. This study assessed the hypothesis that very early exercise exacerbates brain injury, induces reactive oxygen species (ROS generation, and promotes energy failure. A total of 230 adult male Sprague-Dawley rats were subjected to middle cerebral artery (MCA occlusion for 2 h, and randomized into eight groups, including two sham injury control groups, three non-exercise and three exercise groups. Exercise was initiated after 6 h, 24 h and 3 days of reperfusion. Twenty-four hours after completion of exercise (and at corresponding time points in non-exercise controls, infarct volumes and apoptotic cell death were examined. Early brain oxidative metabolism was quantified by examining ROS, ATP and NADH levels 0.5 h after completion of exercise. Furthermore, protein expressions of angiogenic growth factors were measured in order to determine whether post-stroke angiogenesis played a role in rehabilitation. As expected, ischemic stroke resulted in brain infarction, apoptotic cell death and ROS generation, and diminished NADH and ATP production. Infarct volumes and apoptotic cell death were enhanced (p < 0.05 by exercise that was initiated after 6 h of reperfusion, but decreased by late exercise (24 h, 3 days. This exacerbated brain injury at 6 h was associated with increased ROS levels (p < 0.05, and decreased (p < 0.05 NADH and ATP levels. In conclusion, very early exercise aggravated brain damage, and early exercise-induced energy failure with ROS generation may underlie the exacerbation of brain injury. These results shed light on the manner in which exercise initiation timing may affect post-stroke rehabilitation.

  20. Identification of Multipotent Stem Cells in Human Brain Tissue Following Stroke.

    Science.gov (United States)

    Tatebayashi, Kotaro; Tanaka, Yasue; Nakano-Doi, Akiko; Sakuma, Rika; Kamachi, Saeko; Shirakawa, Manabu; Uchida, Kazutaka; Kageyama, Hiroto; Takagi, Toshinori; Yoshimura, Shinichi; Matsuyama, Tomohiro; Nakagomi, Takayuki

    2017-06-01

    Perivascular regions of the brain harbor multipotent stem cells. We previously demonstrated that brain pericytes near blood vessels also develop multipotency following experimental ischemia in mice and these ischemia-induced multipotent stem cells (iSCs) can contribute to neurogenesis. However, it is essential to understand the traits of iSCs in the poststroke human brain for possible applications in stem cell-based therapies for stroke patients. In this study, we report for the first time that iSCs can be isolated from the poststroke human brain. Putative iSCs were derived from poststroke brain tissue obtained from elderly stroke patients requiring decompressive craniectomy and partial lobectomy for diffuse cerebral infarction. Immunohistochemistry showed that these iSCs were localized near blood vessels within poststroke areas containing apoptotic/necrotic neurons and expressed both the stem cell marker nestin and several pericytic markers. Isolated iSCs expressed these same markers and demonstrated high proliferative potential without loss of stemness. Furthermore, isolated iSCs expressed other stem cell markers, such as Sox2, c-myc, and Klf4, and differentiated into multiple cells in vitro, including neurons. These results show that iSCs, which are likely brain pericyte derivatives, are present within the poststroke human brain. This study suggests that iSCs can contribute to neural repair in patients with stroke.

  1. Behavior outcome after ischemic and hemorrhagic stroke, with similar brain damage, in rats.

    Science.gov (United States)

    Mestriner, Régis Gemerasca; Miguel, Patrícia Maidana; Bagatini, Pamela Brambilla; Saur, Lisiani; Boisserand, Lígia Simões Braga; Baptista, Pedro Porto Alegre; Xavier, Léder Leal; Netto, Carlos Alexandre

    2013-05-01

    Stroke causes disability and mortality worldwide and is divided into ischemic and hemorrhagic subtypes. Although clinical trials suggest distinct recovery profiles for ischemic and hemorrhagic events, this is not conclusive due to stroke heterogeneity. The aim of this study was to produce similar brain damage, using experimental models of ischemic (IS) and hemorrhagic (HS) stroke and evaluate the motor spontaneous recovery profile. We used 31 Wistar rats divided into the following groups: Sham (n=7), ischemic (IS) (n=12) or hemorrhagic (HS) (n=12). Brain ischemia or hemorrhage was induced by endotelin-1 (ET-1) and collagenase type IV-S (collagenase) microinjections, respectively. All groups were evaluated in the open field, cylinder and ladder walk behavioral tests at distinct time points as from baseline to 30 days post-surgery (30 PS). Histological and morphometric analyses were used to assess the volume of lost tissue and lesion length. Present results reveal that both forms of experimental stroke had a comparable long-term pattern of damage, since no differences were found in volume of tissue lost or lesion size 30 days after surgery. However, behavioral data showed that hemorrhagic rats were less impaired at skilled walking than ischemic ones at 15 and 30 days post-surgery. We suggest that experimentally comparable stroke design is useful because it reduces heterogeneity and facilitates the assessment of neurobiological differences related to stroke subtypes; and that spontaneous skilled walking recovery differs between experimental ischemic and hemorrhagic insults. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Radio-induced brain lesions

    Directory of Open Access Journals (Sweden)

    Gorgan Mircea Radu

    2014-03-01

    Full Text Available Introduction : Radiotherapy, an important tool in multimodal oncologic treatment, can cause radio-induced brain lesion development after a long period of time following irradiation.

  3. Do brain lesions in stroke affect basic emotions and attachment?

    Science.gov (United States)

    Farinelli, Marina; Panksepp, Jaak; Gestieri, Laura; Maffei, Monica; Agati, Raffaele; Cevolani, Daniela; Pedone, Vincenzo; Northoff, Georg

    2015-01-01

    The aim of the current study was to investigate basic emotions and attachment in a sample of 86 stroke patients. We included a control group of 115 orthopedic patients (matched for age and cognitive status) without brain lesions to control for unspecific general illness effects of a traumatic recent event on basic emotions and attachment. In order to measure basic emotions and attachment style we applied the Affective Neuroscience Personality Scale (ANPS) and the Attachment Style Questionnaire (ASQ). The stroke patients showed significantly different scores in the SEEKING, SADNESS, and ANGER subscales of the ANPS as well as in the Relationship as Secondary Attachment dimension of the ASQ when compared to the control group. These differences show a pattern influenced by lesion location mainly as concerns basic emotions. Anterior, medial, left, and subcortical patients provide scores significantly lower in ANPS-SEEKING than the control group; ANPS-SADNESS scores in anterior, right, medial, and subcortical patients were significantly higher than those of the control group. ANPS-ANGER scores in posterior, right, and lateral patients were significantly higher than those in the control group; finally, the ANPS-FEAR showed slightly lower scores in posterior patients than in the control group. Minor effects on brain lesions were also individuated in the attachment style. Anterior lesion patients showed a significantly higher average score in the ASQ-Need for Approval subscale than the control group. ASQ-Confidence subscale scores differed significantly in stroke patients with lesions in medial brain regions when compared to control subjects. Scores at ANPS and ASQ subscales appear significantly more correlated in stroke patients than in the control group. Such finding of abnormalities, especially concerning basic emotions in stroke brain-lesioned patients, indicates that the effect of brain lesions may enhance the interrelation between basic emotions and attachment with

  4. Non-invasive brain stimulation in early rehabilitation after stroke.

    Science.gov (United States)

    Blesneag, A V; Popa, L; Stan, A D

    2015-01-01

    The new tendency in rehabilitation involves non-invasive tools that, if applied early after stroke, promote neurorecovery. Repetitive transcranial magnetic stimulation and transcranial direct current stimulation may correct the disruption of cortical excitability and effectively contribute to the restoration of movement and speech. The present paper analyses the results of non-invasive brain stimulation (NIBS) trials, highlighting different aspects related to the repetitive transcranial magnetic stimulation frequency, transcranial direct current stimulation polarity, the period and stimulation places in acute and subacute ischemic strokes. The risk of adverse events, the association with motor or language recovery specific training, and the cumulative positive effect evaluation are also discussed.

  5. An associative Brain-Computer-Interface for acute stroke patients

    DEFF Research Database (Denmark)

    Mrachacz-Kersting, Natalie; Stevenson, Andrew James Thomas; Aliakbaryhosseinabadi, Susan

    2016-01-01

    An efficient innovative Brain-Computer-Interface system that empowers chronic stroke patients to control an artificial activation of their lower limb muscle through task specific motor intent has been tested in the past. In the current study it was applied to acute stroke patients. The system...... (tibialis anterior). This activation is precisely and individually timed such that the sensory signal arising from the stimulation reaches the motor cortex during its maximum activation due to the intention. The output of the motor cortical area representing the dorsiflexor muscles was significantly...

  6. Severe Blood–Brain Barrier Disruption in Cardioembolic Stroke

    Directory of Open Access Journals (Sweden)

    Chang Liu

    2018-02-01

    Full Text Available BackgroundPrevious studies demonstrated that cardioembolism (CE was prone to develop hemorrhagic transformation (HT, whereas hyper-permeability of blood–brain barrier (BBB might be one reason for the development of HT. We, thus, aimed to investigate whether the BBB permeability (BBBP was higher in CE stroke than other stroke subtypes in acute ischemic stroke (AIS patients.MethodsThis study was a retrospective review of prospectively collected clinical and imaging database of AIS patients who underwent CT perfusion. Hypoperfusion was defined as Tmax >6 s. The average relative permeability-surface area product (rPS, reflecting the BBBP, was calculated within the hypoperfusion region (rPShypo. CE was diagnosed according to the international Trial of Org 10172 in Acute Stroke Treatment criteria. Receiver operating characteristics (ROC curve analysis was used to determine predictive value of rPShypo for CE. Logistic regression was used to identify independent predictors for CE.ResultsA total of 187 patients were included in the final analysis [median age, 73 (61–80 years; 75 (40.1% females; median baseline National Institutes of Health Stroke Scale score, 12 (7–16]. Median rPShypo was 65.5 (35.8–110.1%. Ninety-seven (51.9% patients were diagnosed as CE. ROC analysis revealed that the optimal rPShypo threshold for CE was 86.71%. The value of rPShypo and the rate of rPShypo>86.71% were significantly higher in patients with CE than other stroke subtypes (p < 0.05, after adjusting for the potential confounds.ConclusionThe extent of BBB disruption is more severe in CE stroke than other stroke subtypes during the hyperacute stage.

  7. Diffusion tensor and volumetric magnetic resonance imaging using an MR-compatible hand-induced robotic device suggests training-induced neuroplasticity in patients with chronic stroke.

    Science.gov (United States)

    Lazaridou, Asimina; Astrakas, Loukas; Mintzopoulos, Dionyssios; Khanicheh, Azadeh; Singhal, Aneesh B; Moskowitz, Michael A; Rosen, Bruce; Tzika, Aria A

    2013-11-01

    Stroke is the third leading cause of mortality and a frequent cause of long-term adult impairment. Improved strategies to enhance motor function in individuals with chronic disability from stroke are thus required. Post‑stroke therapy may improve rehabilitation and reduce long-term disability; however, objective methods for evaluating the specific impact of rehabilitation are rare. Brain imaging studies on patients with chronic stroke have shown evidence for reorganization of areas showing functional plasticity after a stroke. In this study, we hypothesized that brain mapping using a novel magnetic resonance (MR)-compatible hand device in conjunction with state‑of‑the‑art magnetic resonance imaging (MRI) can serve as a novel biomarker for brain plasticity induced by rehabilitative motor training in patients with chronic stroke. This hypothesis is based on the premises that robotic devices, by stimulating brain plasticity, can assist in restoring movement compromised by stroke-induced pathological changes in the brain and that these changes can then be monitored by advanced MRI. We serially examined 15 healthy controls and 4 patients with chronic stroke. We employed a combination of diffusion tensor imaging (DTI) and volumetric MRI using a 3-tesla (3T) MRI system using a 12-channel Siemens Tim coil and a novel MR-compatible hand‑induced robotic device. DTI data revealed that the number of fibers and the average tract length significantly increased after 8 weeks of hand training by 110% and 64%, respectively (probotics in the molecular medicine era.

  8. Stroke-induced immunodepression and dysphagia independently predict stroke-associated pneumonia - The PREDICT study.

    Science.gov (United States)

    Hoffmann, Sarah; Harms, Hendrik; Ulm, Lena; Nabavi, Darius G; Mackert, Bruno-Marcel; Schmehl, Ingo; Jungehulsing, Gerhard J; Montaner, Joan; Bustamante, Alejandro; Hermans, Marcella; Hamilton, Frank; Göhler, Jos; Malzahn, Uwe; Malsch, Carolin; Heuschmann, Peter U; Meisel, Christian; Meisel, Andreas

    2017-12-01

    Stroke-associated pneumonia is a frequent complication after stroke associated with poor outcome. Dysphagia is a known risk factor for stroke-associated pneumonia but accumulating evidence suggests that stroke induces an immunodepressive state increasing susceptibility for stroke-associated pneumonia. We aimed to confirm that stroke-induced immunodepression syndrome is associated with stroke-associated pneumonia independently from dysphagia by investigating the predictive properties of monocytic HLA-DR expression as a marker of immunodepression as well as biomarkers for inflammation (interleukin-6) and infection (lipopolysaccharide-binding protein). This was a prospective, multicenter study with 11 study sites in Germany and Spain, including 486 patients with acute ischemic stroke. Daily screening for stroke-associated pneumonia, dysphagia and biomarkers was performed. Frequency of stroke-associated pneumonia was 5.2%. Dysphagia and decreased monocytic HLA-DR were independent predictors for stroke-associated pneumonia in multivariable regression analysis. Proportion of pneumonia ranged between 0.9% in the higher monocytic HLA-DR quartile (≥21,876 mAb/cell) and 8.5% in the lower quartile (≤12,369 mAb/cell). In the presence of dysphagia, proportion of pneumonia increased to 5.9% and 18.8%, respectively. Patients without dysphagia and normal monocytic HLA-DR expression had no stroke-associated pneumonia risk. We demonstrate that dysphagia and stroke-induced immunodepression syndrome are independent risk factors for stroke-associated pneumonia. Screening for immunodepression and dysphagia might be useful for identifying patients at high risk for stroke-associated pneumonia.

  9. Automated delineation of stroke lesions using brain CT images

    Directory of Open Access Journals (Sweden)

    Céline R. Gillebert

    2014-01-01

    Full Text Available Computed tomographic (CT images are widely used for the identification of abnormal brain tissue following infarct and hemorrhage in stroke. Manual lesion delineation is currently the standard approach, but is both time-consuming and operator-dependent. To address these issues, we present a method that can automatically delineate infarct and hemorrhage in stroke CT images. The key elements of this method are the accurate normalization of CT images from stroke patients into template space and the subsequent voxelwise comparison with a group of control CT images for defining areas with hypo- or hyper-intense signals. Our validation, using simulated and actual lesions, shows that our approach is effective in reconstructing lesions resulting from both infarct and hemorrhage and yields lesion maps spatially consistent with those produced manually by expert operators. A limitation is that, relative to manual delineation, there is reduced sensitivity of the automated method in regions close to the ventricles and the brain contours. However, the automated method presents a number of benefits in terms of offering significant time savings and the elimination of the inter-operator differences inherent to manual tracing approaches. These factors are relevant for the creation of large-scale lesion databases for neuropsychological research. The automated delineation of stroke lesions from CT scans may also enable longitudinal studies to quantify changes in damaged tissue in an objective and reproducible manner.

  10. MR Vascular Fingerprinting in Stroke and Brain Tumors Models.

    Science.gov (United States)

    Lemasson, B; Pannetier, N; Coquery, N; Boisserand, Ligia S B; Collomb, Nora; Schuff, N; Moseley, M; Zaharchuk, G; Barbier, E L; Christen, T

    2016-11-24

    In this study, we evaluated an MRI fingerprinting approach (MRvF) designed to provide high-resolution parametric maps of the microvascular architecture (i.e., blood volume fraction, vessel diameter) and function (blood oxygenation) simultaneously. The method was tested in rats (n = 115), divided in 3 models: brain tumors (9 L, C6, F98), permanent stroke, and a control group of healthy animals. We showed that fingerprinting can robustly distinguish between healthy and pathological brain tissues with different behaviors in tumor and stroke models. In particular, fingerprinting revealed that C6 and F98 glioma models have similar signatures while 9 L present a distinct evolution. We also showed that it is possible to improve the results of MRvF and obtain supplemental information by changing the numerical representation of the vascular network. Finally, good agreement was found between MRvF and conventional MR approaches in healthy tissues and in the C6, F98, and permanent stroke models. For the 9 L glioma model, fingerprinting showed blood oxygenation measurements that contradict results obtained with a quantitative BOLD approach. In conclusion, MR vascular fingerprinting seems to be an efficient technique to study microvascular properties in vivo. Multiple technical improvements are feasible and might improve diagnosis and management of brain diseases.

  11. Late-onset radiation-induced vasculopathy and stroke in a child with medulloblastoma.

    Science.gov (United States)

    Bansal, Lalit R; Belair, Jeffrey; Cummings, Dana; Zuccoli, Giulio

    2015-05-01

    We report a case of a 15-year-old boy who presented to our institution with left-sided weakness and slurred speech. He had a history of medulloblastoma diagnosed at 3 years of age, status postsurgical resection and craniospinal radiation. Magnetic resonance imaging (MRI) of brain revealed a right paramedian pontine infarction, suspected secondary to late-onset radiation-induced vasculopathy of the vertebrobasilar system. Radiation to the brain is associated with increased incidence of ischemic stroke. Clinicians should have a high index of suspicion for stroke when these patients present with new neurologic symptoms. © The Author(s) 2014.

  12. α-linolenic omega-3 fatty acid for stroke protection: from brain preconditioning paradigm to nutrition

    Directory of Open Access Journals (Sweden)

    Blondeau Nicolas

    2011-09-01

    Full Text Available Stroke is the third leading cause of death, due to its high incidence, the severity of the insult, and lack of treatment options. The only therapeutic is restoration of cerebral blood flow achieved by recombinant tissue plasminogen activator treatment, but only approximately 5% of patients receive it. In addition, therapeutics aimed at achieving neuroprotection by blocking the ischemic cascade, as identified in numerous preclinical studies, failed in clinical trials. This failure in translation from experimental models to clinical trials led to a re-evaluation of properties which would constitute the ‘‘best-in class’’ therapeutics to be used against stroke. Given that neuroprotection appears ineffective per se, an emerging direction is to identify therapies, probably combinatorial in nature, which protect the whole neurovascular unit and target timedependent neurotoxic mechanisms. Molecules that activate complex cellular signaling cascades that render the brain resistant to subsequent ischemia, known as preconditioners, offer a novel perspective in stroke protection. Preconditioning elicits complex endogenous neuroprotective responses that act by pleiotropic mechanisms to block death pathways, promote survival pathways and increase resistance. In addition to chemical preconditioners, natural/endogenous compounds such as adenosine, glutamate, lysophospholipids, and omega-3 polyunsaturated fatty acids have been demonstrated to be excellent preconditioners. Consequently, a major new concept in preconditioning to combat stroke is introduced, which is preconditioning achieved through supplementation of an essential item in diet or as a nutraceutical. Several epidemiologic studies suggested a beneficial effect of a seafood/omega-3-enriched diet in cerebral diseases, but the omega-3-induced protective mechanisms are still poorly identified. This review highlights how α-linolenic acid (ALA, the omega-3 polyunsaturated fatty acid precursor

  13. Decoding post-stroke motor function from structural brain imaging

    Directory of Open Access Journals (Sweden)

    Jane M. Rondina

    2016-01-01

    Full Text Available Clinical research based on neuroimaging data has benefited from machine learning methods, which have the ability to provide individualized predictions and to account for the interaction among units of information in the brain. Application of machine learning in structural imaging to investigate diseases that involve brain injury presents an additional challenge, especially in conditions like stroke, due to the high variability across patients regarding characteristics of the lesions. Extracting data from anatomical images in a way that translates brain damage information into features to be used as input to learning algorithms is still an open question. One of the most common approaches to capture regional information from brain injury is to obtain the lesion load per region (i.e. the proportion of voxels in anatomical structures that are considered to be damaged. However, no systematic evaluation has yet been performed to compare this approach with using patterns of voxels (i.e. considering each voxel as a single feature. In this paper we compared both approaches applying Gaussian Process Regression to decode motor scores in 50 chronic stroke patients based solely on data derived from structural MRI. For both approaches we compared different ways to delimit anatomical areas: regions of interest from an anatomical atlas, the corticospinal tract, a mask obtained from fMRI analysis with a motor task in healthy controls and regions selected using lesion-symptom mapping. Our analysis showed that extracting features through patterns of voxels that represent lesion probability produced better results than quantifying the lesion load per region. In particular, from the different ways to delimit anatomical areas compared, the best performance was obtained with a combination of a range of cortical and subcortical motor areas as well as the corticospinal tract. These results will inform the appropriate methodology for predicting long term motor outcomes

  14. Astrocyte-Derived Pentraxin 3 Supports Blood-Brain Barrier Integrity Under Acute Phase of Stroke.

    Science.gov (United States)

    Shindo, Akihiro; Maki, Takakuni; Mandeville, Emiri T; Liang, Anna C; Egawa, Naohiro; Itoh, Kanako; Itoh, Naoki; Borlongan, Mia; Holder, Julie C; Chuang, Tsu Tshen; McNeish, John D; Tomimoto, Hidekazu; Lok, Josephine; Lo, Eng H; Arai, Ken

    2016-04-01

    Pentraxin 3 (PTX3) is released on inflammatory responses in many organs. However, roles of PTX3 in brain are still mostly unknown. Here we asked whether and how PTX3 contributes to blood-brain barrier dysfunction during the acute phase of ischemic stroke. In vivo, spontaneously hypertensive rats were subjected to focal cerebral ischemia by transient middle cerebral artery occlusion. At day 3, brains were analyzed to evaluate the cellular origin of PTX3 expression. Correlations with blood-brain barrier breakdown were assessed by IgG staining. In vitro, rat primary astrocytes and rat brain endothelial RBE.4 cells were cultured to study the role of astrocyte-derived PTX3 on vascular endothelial growth factor-mediated endothelial permeability. During the acute phase of stroke, reactive astrocytes in the peri-infarct area expressed PTX3. There was negative correlation between gradients of IgG leakage and PTX3-positive astrocytes. Cell culture experiments showed that astrocyte-conditioned media increased levels of tight junction proteins and reduced endothelial permeability under normal conditions. Removing PTX3 from astrocyte-conditioned media by immunoprecipitation increased endothelial permeability. PTX3 strongly bound vascular endothelial growth factor in vitro and was able to decrease vascular endothelial growth factor-induced endothelial permeability. Astrocytes in peri-infarct areas upregulate PTX3, which may support blood-brain barrier integrity by regulating vascular endothelial growth factor-related mechanisms. This response in astrocytes may comprise a compensatory mechanism for maintaining blood-brain barrier function after ischemic stroke. © 2016 American Heart Association, Inc.

  15. Models to Tailor Brain Stimulation Therapies in Stroke

    Directory of Open Access Journals (Sweden)

    E. B. Plow

    2016-01-01

    Full Text Available A great challenge facing stroke rehabilitation is the lack of information on how to derive targeted therapies. As such, techniques once considered promising, such as brain stimulation, have demonstrated mixed efficacy across heterogeneous samples in clinical studies. Here, we explain reasons, citing its one-type-suits-all approach as the primary cause of variable efficacy. We present evidence supporting the role of alternate substrates, which can be targeted instead in patients with greater damage and deficit. Building on this groundwork, this review will also discuss different frameworks on how to tailor brain stimulation therapies. To the best of our knowledge, our report is the first instance that enumerates and compares across theoretical models from upper limb recovery and conditions like aphasia and depression. Here, we explain how different models capture heterogeneity across patients and how they can be used to predict which patients would best respond to what treatments to develop targeted, individualized brain stimulation therapies. Our intent is to weigh pros and cons of testing each type of model so brain stimulation is successfully tailored to maximize upper limb recovery in stroke.

  16. Harnessing the potential of biomaterials for brain repair after stroke

    Science.gov (United States)

    Tuladhar, Anup; Payne, Samantha L.; Shoichet, Molly S.

    2018-03-01

    Stroke is a devastating disease for which no clinical treatment exists to regenerate lost tissue. Strategies for brain repair in animal models of stroke include the delivery of drug or cell-based therapeutics; however, the complex anatomy and functional organization of the brain presents many challenges. Biomaterials may alleviate some of these challenges by providing a scaffold, localizing the therapy to the site of action, and/or modulating cues to brain cells. Here, the challenges associated with delivery of therapeutics to the brain and the biomaterial strategies used to overcome these challenges are described. For example, innovative hydrogel delivery systems have been designed to provide sustained trophic factor delivery for endogenous repair and to support transplanted cell survival and integration. Novel treatments, such as electrical stimulation of transplanted cells and the delivery of factors for the direct reprogramming of astrocytes into neurons, may be further enhanced by biomaterial delivery systems. Ultimately, improved clinical translation will be achieved by combining clinically relevant therapies with biomaterials strategies.

  17. Functional Brain Correlates of Upper Limb Spasticity and Its Mitigation following Rehabilitation in Chronic Stroke Survivors

    Science.gov (United States)

    Pundik, Svetlana; Falchook, Adam D.; McCabe, Jessica; Daly, Janis J.

    2014-01-01

    Background. Arm spasticity is a challenge in the care of chronic stroke survivors with motor deficits. In order to advance spasticity treatments, a better understanding of the mechanism of spasticity-related neuroplasticity is needed. Objective. To investigate brain function correlates of spasticity in chronic stroke and to identify specific regional functional brain changes related to rehabilitation-induced mitigation of spasticity. Methods. 23 stroke survivors (>6 months) were treated with an arm motor learning and spasticity therapy (5 d/wk for 12 weeks). Outcome measures included Modified Ashworth scale, sensory tests, and functional magnetic resonance imaging (fMRI) for wrist and hand movement. Results. First, at baseline, greater spasticity correlated with poorer motor function (P = 0.001) and greater sensory deficits (P = 0.003). Second, rehabilitation produced improvement in upper limb spasticity and motor function (P spasticity correlated with higher fMRI activation in the ipsilesional thalamus (rho = 0.49, P = 0.03). Fourth, following rehabilitation, greater mitigation of spasticity correlated with enhanced fMRI activation in the contralesional primary motor (r = −0.755, P = 0.003), premotor (r = −0.565, P = 0.04), primary sensory (r = −0.614, P = 0.03), and associative sensory (r = −0.597, P = 0.03) regions while controlling for changes in motor function. Conclusions. Contralesional motor regions may contribute to restoring control of muscle tone in chronic stroke. PMID:25101190

  18. Adapting the concepts of brain and cognitive reserve to post-stroke cognitive deficits: Implications for understanding neglect.

    Science.gov (United States)

    Umarova, Roza M

    2017-12-01

    Advanced lesion mapping and connectivity analyses are currently the main tools used to understand the mechanisms underlying post-stroke cognitive deficits. However, the factors contributing to pre-stroke architecture of cognitive networks are often ignored, even though they reportedly play a decisive role in the manifestation of cognitive impairment in neurodegeneration. The present review on post-stroke cognitive deficits therefore adopts the concept of brain and cognitive reserve, which was originally developed to account for the individual differences in the course of aging and neurodegenerative diseases. By focusing on spatial neglect, a typical network disorder, it is discussed how individual susceptibility to stroke lesion might explain the reported discrepancies in lesion anatomy, non-spatial deficits and recovery courses. A detailed analysis of the literature reveals that premorbid brain (age, brain atrophy, previous strokes, leukoaraiosis, genetic factors, etc.) and cognitive reserve (IQ, life experience, education, occupation, premorbid cognitive impairment, etc.) greatly impact the brain's capacity for compensation. Furthermore, the interaction between pre-stroke brain/cognitive reserve and the degree of stroke-induced system impairment (e.g., hypoperfusion, lesion load) determines both the extent of neglect symptoms variability and the course of recovery. Premorbid brain/cognitive reserves should thus be considered to: (i) understand the mechanisms of post-stroke cognitive disorders and sufficiently explain their inter-individual variability; (ii) provide a prognosis for cognitive recovery and hence post-stroke dependency; (iii) identify individual targets for cognitive rehabilitation: in the case of reduced brain/cognitive reserve, neglect might occur even with a confined lesion, and non-spatial training of general attentional capacity should represent the main therapeutic target also for treatment of neglect; this might be true also for non

  19. Protein-Energy Malnutrition Exacerbates Stroke-Induced Forelimb Abnormalities and Dampens Neuroinflammation.

    Science.gov (United States)

    Alaverdashvili, Mariam; Caine, Sally; Li, Xue; Hackett, Mark J; Bradley, Michael P; Nichol, Helen; Paterson, Phyllis G

    2018-02-03

    Protein-energy malnutrition (PEM) pre-existing at stroke onset is believed to worsen functional outcome, yet the underlying mechanisms are not fully understood. Since brain inflammation is an important modulator of neurological recovery after stroke, we explored the impact of PEM on neuroinflammation in the acute period in relation to stroke-initiated sensori-motor abnormalities. Adult rats were fed a low-protein (LP) or normal protein (NP) diet for 28 days before inducing photothrombotic stroke (St) in the forelimb region of the motor cortex or sham surgery; the diets continued for 3 days after the stroke. Protein-energy status was assessed by a combination of body weight, food intake, serum acute phase proteins and corticosterone, and liver lipid content. Deficits in motor function were evaluated in the horizontal ladder walking and cylinder tasks at 3 days after stroke. The glial response and brain elemental signature were investigated by immunohistochemistry and micro-X-ray fluorescence imaging, respectively. The LP-fed rats reduced food intake, resulting in PEM. Pre-existing PEM augmented stroke-induced abnormalities in forelimb placement accuracy on the ladder; LP-St rats made more errors (29 ± 8%) than the NP-St rats (15 ± 3%; P < 0.05). This was accompanied by attenuated astrogliosis in the peri-infarct area by 18% and reduced microglia activation by up to 41 and 21% in the peri-infarct area and the infarct rim, respectively (P < 0.05). The LP diet altered the cortical Zn, Ca, and Cl signatures (P < 0.05). Our data suggest that proactive treatment of pre-existing PEM could be essential for optimal post-stroke recovery.

  20. Effects of vibratory stimulation-induced kinesthetic illusions on the neural activities of patients with stroke.

    Science.gov (United States)

    Kodama, Takayuki; Nakano, Hideki; Ohsugi, Hironori; Murata, Shin

    2016-01-01

    [Purpose] This study evaluated the influence of vibratory stimulation-induced kinesthetic illusion on brain function after stroke. [Subjects] Twelve healthy individuals and 13 stroke patients without motor or sensory loss participated. [Methods] Electroencephalograms were taken at rest and during vibratory stimulation. As a neurophysiological index of brain function, we measured the μ-rhythm, which is present mainly in the kinesthetic cortex and is attenuated by movement or motor imagery and compared the data using source localization analyses in the Standardized Low Resolution Brain Electromagnetic Tomography (sLORETA) program. [Results] At rest, μ-rhythms appeared in the sensorimotor and supplementary motor cortices in both healthy controls and stroke patients. Under vibratory stimulation, no μ-rhythm appeared in the sensorimotor cortex of either group. Moreover, in the supplementary motor area, which stores the motor imagery required for kinesthetic illusions, the μ-rhythms of patients were significantly stronger than those of the controls, although the μ-rhythms of both groups were reduced. Thus, differences in neural activity in the supplementary motor area were apparent between the subject groups. [Conclusion] Kinesthetic illusions do occur in patients with motor deficits due to stroke. The neural basis of the supplementary motor area in stroke patients may be functionally different from that found in healthy controls.

  1. Prediction of stroke thrombolysis outcome using CT brain machine learning

    Directory of Open Access Journals (Sweden)

    Paul Bentley

    2014-01-01

    Full Text Available A critical decision-step in the emergency treatment of ischemic stroke is whether or not to administer thrombolysis — a treatment that can result in good recovery, or deterioration due to symptomatic intracranial haemorrhage (SICH. Certain imaging features based upon early computerized tomography (CT, in combination with clinical variables, have been found to predict SICH, albeit with modest accuracy. In this proof-of-concept study, we determine whether machine learning of CT images can predict which patients receiving tPA will develop SICH as opposed to showing clinical improvement with no haemorrhage. Clinical records and CT brains of 116 acute ischemic stroke patients treated with intravenous thrombolysis were collected retrospectively (including 16 who developed SICH. The sample was split into training (n = 106 and test sets (n = 10, repeatedly for 1760 different combinations. CT brain images acted as inputs into a support vector machine (SVM, along with clinical severity. Performance of the SVM was compared with established prognostication tools (SEDAN and HAT scores; original, or after adaptation to our cohort. Predictive performance, assessed as area under receiver-operating-characteristic curve (AUC, of the SVM (0.744 compared favourably with that of prognostic scores (original and adapted versions: 0.626–0.720; p < 0.01. The SVM also identified 9 out of 16 SICHs, as opposed to 1–5 using prognostic scores, assuming a 10% SICH frequency (p < 0.001. In summary, machine learning methods applied to acute stroke CT images offer automation, and potentially improved performance, for prediction of SICH following thrombolysis. Larger-scale cohorts, and incorporation of advanced imaging, should be tested with such methods.

  2. Stroke and Drug Delivery--In Vitro Models of the Ischemic Blood-Brain Barrier

    DEFF Research Database (Denmark)

    Tornabene, Erica; Brodin, Birger

    2016-01-01

    Stroke is a major cause of death and disability worldwide. Both cerebral hypoperfusion and focal cerebral infarcts are caused by a reduction of blood flow to the brain, leading to stroke and subsequent brain damage. At present, only few medical treatments of stroke are available, with the Food...... and Drug Administration-approved tissue plasminogen activator for treatment of acute ischemic stroke being the most prominent example. A large number of potential drug candidates for treatment of ischemic brain tissue have been developed and subsequently failed in clinical trials. A deeper understanding...... of permeation pathways across the barrier in ischemic and postischemic brain endothelium is important for development of new medical treatments. The blood-brain barrier, that is, the endothelial monolayer lining the brain capillaries, changes properties during an ischemic event. In vitro models of the blood-brain...

  3. Systematic Analysis of RNA Regulatory Network in Rat Brain after Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Juan Liu

    2018-01-01

    Full Text Available Although extensive studies have identified large number of microRNAs (miRNAs and long noncoding RNAs (lncRNAs in ischemic stroke, the RNA regulation network response to focal ischemia remains poorly understood. In this study, we simultaneously interrogate the expression profiles of lncRNAs, miRNAs, and mRNAs changes during focal ischemia induced by transient middle cerebral artery occlusion. A set of 1924 novel lncRNAs were identified and may involve brain injury and DNA repair as revealed by coexpression network analysis. Furthermore, many short interspersed elements (SINE mediated lncRNA:mRNA duplexes were identified, implying that lncRNAs mediate Staufen1-mediated mRNA decay (SMD which may play a role during focal ischemia. Moreover, based on the competitive endogenous RNA (ceRNA hypothesis, a stroke regulatory ceRNA network which reveals functional lncRNA:miRNA:mRNA interactions was revealed in ischemic stroke. In brief, this work reports a large number of novel lncRNAs responding to focal ischemia and constructs a systematic RNA regulation network which highlighted the role of ncRNAs in ischemic stroke.

  4. Inhibition of myeloperoxidase oxidant production by N-acetyl lysyltyrosylcysteine amide reduces brain damage in a murine model of stroke.

    Science.gov (United States)

    Yu, Guoliang; Liang, Ye; Huang, Ziming; Jones, Deron W; Pritchard, Kirkwood A; Zhang, Hao

    2016-05-24

    Oxidative stress plays an important and causal role in the mechanisms by which ischemia/reperfusion (I/R) injury increases brain damage after stroke. Accordingly, reducing oxidative stress has been proposed as a therapeutic strategy for limiting damage in the brain after stroke. Myeloperoxidase (MPO) is a highly potent oxidative enzyme that is capable of inducing both oxidative and nitrosative stress in vivo. To determine if and the extent to which MPO-generated oxidants contribute to brain I/R injury, we treated mice subjected to middle cerebral artery occlusion (MCAO) with N-acetyl lysyltyrosylcysteine amide (KYC), a novel, specific and non-toxic inhibitor of MPO. Behavioral testing, ischemic damage, blood-brain-barrier disruption, apoptosis, neutrophils infiltration, microglia/macrophage activation, and MPO oxidation were analyzed within a 7-day period after MCAO. Our studies show that KYC treatment significantly reduces neurological severity scores, infarct size, IgG extravasation, neutrophil infiltration, loss of neurons, apoptosis, and microglia/macrophage activation in the brains of MCAO mice. Immunofluorescence studies show that KYC treatment reduces the formation of chlorotyrosine (ClTyr), a fingerprint biomarker of MPO oxidation, nitrotyrosine (NO2Tyr), and 4-hydroxynonenal (4HNE) in MCAO mice. All oxidative products colocalized with MPO in the infarcted brains, suggesting that MPO-generated oxidants are involved in forming the oxidative products. MPO-generated oxidants play detrimental roles in causing brain damage after stroke which is effectively reduced by KYC.

  5. Evaluation of role of brain SPECT in diagnosis of post stroke dementia

    International Nuclear Information System (INIS)

    Yousepour, G.; Alavi, M.

    2003-01-01

    Post stroke dementia is one of the most common complications of stroke that is preventable and relatively treatable too. The purpose of the study is comparison between the positive findings in the brain CT scan and brain perfusion SPECT. 15 patients who were complicated by dementia after cerebrovascular accident and also 5 patients as a control group enrolled in this study. Brain CT scan and brain SPECT were performed during at most one week after stroke. Abnormal findings in both brain CT scan and SPECT were seen in 46% of patients. Brain CT scan disclosed more abnormal findings compared to brain SPECT (33.3%). While brain SPECT findings were more information than brain CT scan (20%) this study is indicating that brain CT scan and the brain SPECT concomitantly for each other in better diagnosis of post stroke dementia. We did not find any specific diagnostic pattern in brain SPECT of patients suffering from post stroke dementia. The low quality of brain SPECT in spite of uniformity of gamma camera may be suggestive of low quality of Iran produced ECD kit that needs further evaluation

  6. Burden and outcome of prevalent ischemic brain disease in a national acute stroke registry.

    Science.gov (United States)

    Koton, Silvia; Tsabari, Rakefet; Molshazki, Noa; Kushnir, Moshe; Shaien, Radi; Eilam, Anda; Tanne, David

    2013-12-01

    Previous overt stroke and subclinical stroke are frequent in patients with stroke; yet, their clinical significance and effects on stroke outcome are not clear. We studied the burden and outcome after acute ischemic stroke by prevalent ischemic brain disease in a national registry of hospitalized patients with acute stroke. Patients with ischemic stroke in the National Acute Stroke Israeli prospective hospital-based registry (February to March 2004, March to April 2007, and April to May 2010) with information on previous overt stroke and subclinical stroke per computed tomography/MRI (n=3757) were included. Of them, a subsample (n=787) was followed up at 3 months. Logistic regression models were computed for outcomes in patients with prior overt stroke or subclinical stroke, compared with patients with first stroke, adjusting for age, sex, vascular risk factors, stroke severity, and clinical classification. Two-thirds of patients had a prior overt stroke or subclinical stroke. Death rates were similar for patients with and without prior stroke. Adjusted odds ratios (OR; 95% confidence interval [CI]) for disability were increased for patients with prior overt stroke (OR, 1.31; 95% CI, 1.03-1.66) and subclinical stroke (OR, 1.45; 95% CI, 1.16-1.82). Relative odds of Barthel Index≤60 for patients with prior overt stroke (OR, 2.04; 95% CI, 1.14-3.68) and with prior subclinical stroke (OR, 2.04; 95% CI, 1.15-3.64) were twice higher than for patients with a first stroke. ORs for dependency were significantly increased for patients with prior overt stroke (OR, 1.95; 95% CI, 1.19-3.20) but not for those with subclinical stroke (OR, 1.36; 95% CI, 0.84-2.19). In our national cohort of patients with acute ischemic stroke, nearly two thirds had a prior overt stroke or subclinical stroke. Risk of poor functional outcomes was increased for patients with prior stroke, both overt and subclinical.

  7. MR-visible brain water content in human acute stroke

    DEFF Research Database (Denmark)

    Gideon, P; Rosenbaum, S; Sperling, B

    1999-01-01

    Quantification of metabolite concentrations by proton magnetic resonance spectroscopy (1H-MRS) in the human brain using water as an internal standard is based on the assumption that water content does not change significantly in pathologic brain tissue. To test this, we used 1H-MRS to estimate...... brain water content during the course of cerebral infarction. Measurements were performed serially in the acute, subacute, and chronic phase of infarction. Fourteen patients with acute cerebral infarction were examined as well as 9 healthy controls. To correlate with regional cerebral blood flow (r......CBF) SPECT-scanning using 99mTc-HMPAO as flow tracer was performed in the patients. Mean water content (SD) in the infarct area was 37.7 (5.1); 41.8 (4.8); 35.2 (5.4); and 39.3 (5.1) mol x [kg wet weight](-1) at 0-3; 4-7; 8-21; and >180 days after stroke, respectively. Water content increased between Day 0...

  8. Functional Brain Correlates of Upper Limb Spasticity and Its Mitigation following Rehabilitation in Chronic Stroke Survivors

    Directory of Open Access Journals (Sweden)

    Svetlana Pundik

    2014-01-01

    Full Text Available Background. Arm spasticity is a challenge in the care of chronic stroke survivors with motor deficits. In order to advance spasticity treatments, a better understanding of the mechanism of spasticity-related neuroplasticity is needed. Objective. To investigate brain function correlates of spasticity in chronic stroke and to identify specific regional functional brain changes related to rehabilitation-induced mitigation of spasticity. Methods. 23 stroke survivors (>6 months were treated with an arm motor learning and spasticity therapy (5 d/wk for 12 weeks. Outcome measures included Modified Ashworth scale, sensory tests, and functional magnetic resonance imaging (fMRI for wrist and hand movement. Results. First, at baseline, greater spasticity correlated with poorer motor function (P=0.001 and greater sensory deficits (P=0.003. Second, rehabilitation produced improvement in upper limb spasticity and motor function (P<0.0001. Third, at baseline, greater spasticity correlated with higher fMRI activation in the ipsilesional thalamus (rho=0.49, P=0.03. Fourth, following rehabilitation, greater mitigation of spasticity correlated with enhanced fMRI activation in the contralesional primary motor (r=-0.755, P=0.003, premotor (r=−0.565, P=0.04, primary sensory (r=−0.614, P=0.03, and associative sensory (r=−0.597, P=0.03 regions while controlling for changes in motor function. Conclusions. Contralesional motor regions may contribute to restoring control of muscle tone in chronic stroke.

  9. Diffusion tensor and volumetric magnetic resonance imaging using an MR-compatible hand-induced robotic device suggests training-induced neuroplasticity in patients with chronic stroke

    Science.gov (United States)

    LAZARIDOU, ASIMINA; ASTRAKAS, LOUKAS; MINTZOPOULOS, DIONYSSIOS; KHANICHEH, AZADEH; SINGHAL, ANEESH B.; MOSKOWITZ, MICHAEL A.; ROSEN, BRUCE; TZIKA, ARIA A.

    2013-01-01

    Stroke is the third leading cause of mortality and a frequent cause of long-term adult impairment. Improved strategies to enhance motor function in individuals with chronic disability from stroke are thus required. Post-stroke therapy may improve rehabilitation and reduce long-term disability; however, objective methods for evaluating the specific impact of rehabilitation are rare. Brain imaging studies on patients with chronic stroke have shown evidence for reorganization of areas showing functional plasticity after a stroke. In this study, we hypothesized that brain mapping using a novel magnetic resonance (MR)-compatible hand device in conjunction with state-of-the-art magnetic resonance imaging (MRI) can serve as a novel biomarker for brain plasticity induced by rehabilitative motor training in patients with chronic stroke. This hypothesis is based on the premises that robotic devices, by stimulating brain plasticity, can assist in restoring movement compromised by stroke-induced pathological changes in the brain and that these changes can then be monitored by advanced MRI. We serially examined 15 healthy controls and 4 patients with chronic stroke. We employed a combination of diffusion tensor imaging (DTI) and volumetric MRI using a 3-tesla (3T) MRI system using a 12-channel Siemens Tim coil and a novel MR-compatible hand-induced robotic device. DTI data revealed that the number of fibers and the average tract length significantly increased after 8 weeks of hand training by 110% and 64%, respectively (pneuroplasticity. Our study is an example of personalized medicine using advanced neuroimaging methods in conjunction with robotics in the molecular medicine era. PMID:23982596

  10. Clinical evaluation of patients with migraine induced stroke in mashhad, iran.

    Science.gov (United States)

    Ghandehari, Kavian; Sharifi, Atena; Nikbin, Zeynab; Fadaei, Sahar; Meybodi, Meysam Aghaei; Moshfegh, Mehdi; Hosseini, Mohammad Reza; Sarabi, Mohammad Reza Gerami; Maarufi, Parham

    2010-01-01

    Migraine Induced Stroke (MIS) is an important cause of brain infarction in the young people. Consecutive patients with MIS admitted in Ghaem hospital, Mashhad during 2006-2010 enrolled a prospective clinical study. All of the patients suspected to MIS had brain MRI with a 0.5 Tesla generation, Philips NT Intra, Netherland. All of the MIS patients underwent a standard battery of diagnostic investigations for detecting etiology of stroke. Disability of MIS patients was detected based on the modified Rankin scale at 90 days post stroke. 32 MIS patients (18 females, 14 males) with mean age 37.2 ± 3.8 years ranged 15-58 years were evaluated. Hypodense area of infarction corresponding to clinical manifestations was detected in MRI in 32% of our MIS patients. The mean disability score in our MIS patients was 1.09 ± 0.32, which is significantly lower than other stroke patients (z = 2.55, P = 0.007) MIS is an important cause of stroke in Persian young adults which have good prognosis.

  11. Non-Gaussian diffusion imaging for enhanced contrast of brain tissue affected by ischemic stroke.

    Science.gov (United States)

    Grinberg, Farida; Farrher, Ezequiel; Ciobanu, Luisa; Geffroy, Françoise; Le Bihan, Denis; Shah, N Jon

    2014-01-01

    Recent diffusion MRI studies of stroke in humans and animals have shown that the quantitative parameters characterising the degree of non-Gaussianity of the diffusion process are much more sensitive to ischemic changes than the apparent diffusion coefficient (ADC) considered so far as the "gold standard". The observed changes exceeded that of the ADC by a remarkable factor of 2 to 3. These studies were based on the novel non-Gaussian methods, such as diffusion kurtosis imaging (DKI) and log-normal distribution function imaging (LNDFI). As shown in our previous work investigating the animal stroke model, a combined analysis using two methods, DKI and LNDFI provides valuable complimentary information. In the present work, we report the application of three non-Gaussian diffusion models to quantify the deviations from the Gaussian behaviour in stroke induced by transient middle cerebral artery occlusion in rat brains: the gamma-distribution function (GDF), the stretched exponential model (SEM), and the biexponential model. The main goal was to compare the sensitivity of various non-Gaussian metrics to ischemic changes and to investigate if a combined application of several models will provide added value in the assessment of stroke. We have shown that two models, GDF and SEM, exhibit a better performance than the conventional method and allow for a significantly enhanced visualization of lesions. Furthermore, we showed that valuable information regarding spatial properties of stroke lesions can be obtained. In particular, we observed a stratified cortex structure in the lesions that were well visible in the maps of the GDF and SEM metrics, but poorly distinguishable in the ADC-maps. Our results provided evidence that cortical layers tend to be differently affected by ischemic processes.

  12. Non-Gaussian diffusion imaging for enhanced contrast of brain tissue affected by ischemic stroke.

    Directory of Open Access Journals (Sweden)

    Farida Grinberg

    Full Text Available Recent diffusion MRI studies of stroke in humans and animals have shown that the quantitative parameters characterising the degree of non-Gaussianity of the diffusion process are much more sensitive to ischemic changes than the apparent diffusion coefficient (ADC considered so far as the "gold standard". The observed changes exceeded that of the ADC by a remarkable factor of 2 to 3. These studies were based on the novel non-Gaussian methods, such as diffusion kurtosis imaging (DKI and log-normal distribution function imaging (LNDFI. As shown in our previous work investigating the animal stroke model, a combined analysis using two methods, DKI and LNDFI provides valuable complimentary information. In the present work, we report the application of three non-Gaussian diffusion models to quantify the deviations from the Gaussian behaviour in stroke induced by transient middle cerebral artery occlusion in rat brains: the gamma-distribution function (GDF, the stretched exponential model (SEM, and the biexponential model. The main goal was to compare the sensitivity of various non-Gaussian metrics to ischemic changes and to investigate if a combined application of several models will provide added value in the assessment of stroke. We have shown that two models, GDF and SEM, exhibit a better performance than the conventional method and allow for a significantly enhanced visualization of lesions. Furthermore, we showed that valuable information regarding spatial properties of stroke lesions can be obtained. In particular, we observed a stratified cortex structure in the lesions that were well visible in the maps of the GDF and SEM metrics, but poorly distinguishable in the ADC-maps. Our results provided evidence that cortical layers tend to be differently affected by ischemic processes.

  13. Transcriptomics of Post-Stroke Angiogenesis in the Aged Brain

    OpenAIRE

    Buga, Ana Maria; Margaritescu, Claudiu; Scholz, Claus Juergen; Radu, Eugen; Zelenak, Christine; Popa-Wagner, Aurel

    2014-01-01

    Despite the obvious clinical significance of post-stroke angiogenesis in aged subjects, a detailed transcriptomic analysis of post-stroke angiogenesis has not yet been undertaken in an aged experimental model. In this study, by combining stroke transcriptomics with immunohistochemistry in aged rats and post-stroke patients, we sought to identify an age-specific gene expression pattern that may characterize the angiogenic process after stroke. We found that both young and old infarcted rats in...

  14. Stroke and Cerebrovascular Diseases Registry

    Science.gov (United States)

    2017-09-11

    Stroke; Acute Stroke; Acute Brain Injury; Ischemic Stroke; Hemorrhagic Stroke; Transient Ischemic Attack; Subarachnoid Hemorrhage; Cerebral Ischemia; Cerebral Infarction; Cerebral Stroke; Venous Sinus Thrombosis, Cranial

  15. The impact of large structural brain changes in chronic stroke patients on the electric field caused by transcranial brain stimulation

    Directory of Open Access Journals (Sweden)

    Sena Minjoli

    2017-01-01

    Full Text Available Transcranial magnetic stimulation (TMS and transcranial direct current stimulation (TDCS are two types of non-invasive transcranial brain stimulation (TBS. They are useful tools for stroke research and may be potential adjunct therapies for functional recovery. However, stroke often causes large cerebral lesions, which are commonly accompanied by a secondary enlargement of the ventricles and atrophy. These structural alterations substantially change the conductivity distribution inside the head, which may have potentially important consequences for both brain stimulation methods. We therefore aimed to characterize the impact of these changes on the spatial distribution of the electric field generated by both TBS methods. In addition to confirming the safety of TBS in the presence of large stroke-related structural changes, our aim was to clarify whether targeted stimulation is still possible. Realistic head models containing large cortical and subcortical stroke lesions in the right parietal cortex were created using MR images of two patients. For TMS, the electric field of a double coil was simulated using the finite-element method. Systematic variations of the coil position relative to the lesion were tested. For TDCS, the finite-element method was used to simulate a standard approach with two electrode pads, and the position of one electrode was systematically varied. For both TMS and TDCS, the lesion caused electric field “hot spots” in the cortex. However, these maxima were not substantially stronger than those seen in a healthy control. The electric field pattern induced by TMS was not substantially changed by the lesions. However, the average field strength generated by TDCS was substantially decreased. This effect occurred for both head models and even when both electrodes were distant to the lesion, caused by increased current shunting through the lesion and enlarged ventricles. Judging from the similar peak field strengths compared

  16. The impact of large structural brain changes in chronic stroke patients on the electric field caused by transcranial brain stimulation.

    Science.gov (United States)

    Minjoli, Sena; Saturnino, Guilherme B; Blicher, Jakob Udby; Stagg, Charlotte J; Siebner, Hartwig R; Antunes, André; Thielscher, Axel

    2017-01-01

    Transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (TDCS) are two types of non-invasive transcranial brain stimulation (TBS). They are useful tools for stroke research and may be potential adjunct therapies for functional recovery. However, stroke often causes large cerebral lesions, which are commonly accompanied by a secondary enlargement of the ventricles and atrophy. These structural alterations substantially change the conductivity distribution inside the head, which may have potentially important consequences for both brain stimulation methods. We therefore aimed to characterize the impact of these changes on the spatial distribution of the electric field generated by both TBS methods. In addition to confirming the safety of TBS in the presence of large stroke-related structural changes, our aim was to clarify whether targeted stimulation is still possible. Realistic head models containing large cortical and subcortical stroke lesions in the right parietal cortex were created using MR images of two patients. For TMS, the electric field of a double coil was simulated using the finite-element method. Systematic variations of the coil position relative to the lesion were tested. For TDCS, the finite-element method was used to simulate a standard approach with two electrode pads, and the position of one electrode was systematically varied. For both TMS and TDCS, the lesion caused electric field "hot spots" in the cortex. However, these maxima were not substantially stronger than those seen in a healthy control. The electric field pattern induced by TMS was not substantially changed by the lesions. However, the average field strength generated by TDCS was substantially decreased. This effect occurred for both head models and even when both electrodes were distant to the lesion, caused by increased current shunting through the lesion and enlarged ventricles. Judging from the similar peak field strengths compared to the healthy

  17. Relationships between brain and body temperature, clinical and imaging outcomes after ischemic stroke

    Science.gov (United States)

    Karaszewski, Bartosz; Carpenter, Trevor K; Thomas, Ralph G R; Armitage, Paul A; Lymer, Georgina Katherine S; Marshall, Ian; Dennis, Martin S; Wardlaw, Joanna M

    2013-01-01

    Pyrexia soon after stroke is associated with severe stroke and poor functional outcome. Few studies have assessed brain temperature after stroke in patients, so little is known of its associations with body temperature, stroke severity, or outcome. We measured temperatures in ischemic and normal-appearing brain using 1H-magnetic resonance spectroscopy and its correlations with body (tympanic) temperature measured four-hourly, infarct growth by 5 days, early neurologic (National Institute of Health Stroke Scale, NIHSS) and late functional outcome (death or dependency). Among 40 patients (mean age 73 years, median NIHSS 7, imaged at median 17 hours), temperature in ischemic brain was higher than in normal-appearing brain on admission (38.6°C-core, 37.9°C-contralateral hemisphere, P=0.03) but both were equally elevated by 5 days; both were higher than tympanic temperature. Ischemic lesion temperature was not associated with NIHSS or 3-month functional outcome; in contrast, higher contralateral normal-appearing brain temperature was associated with worse NIHSS, infarct expansion and poor functional outcome, similar to associations for tympanic temperature. We conclude that brain temperature is higher than body temperature; that elevated temperature in ischemic brain reflects a local tissue response to ischemia, whereas pyrexia reflects the systemic response to stroke, occurs later, and is associated with adverse outcomes. PMID:23571281

  18. Exogenous stem cells pioneer a biobridge to the advantage of host brain cells following stroke: New insights for clinical applications

    Directory of Open Access Journals (Sweden)

    Marci G Crowley

    2017-01-01

    Full Text Available Stroke continues to maintain its status as one of the top causes of mortality within the United States. Currently, the only Food and Drug Administration (FDA-approved drug in place for stroke patients, tissue plasminogen activator (tPA, has a rigid therapeutic window, closing at approximately 4.5 h after stroke onset. Due to this short time frame and other restrictions, such as any condition that increases a patient's risk for hemorrhaging, it has been predicted that <5% of ischemic stroke patients benefit from tPA. Given that rehabilitation therapy remains the only other option for stroke victims, there is a clear unmet clinical need for treatment available for the remaining 95%. While still considered an experimental treatment, the utilization of stem cell therapies for stroke holds consistent promise. Copious preclinical studies report the capacity for transplanted stem cells to rescue the brain parenchyma surrounding the stroke-induced infarct core. At present, the exact mechanisms in which stem cells contribute a robust therapeutic benefit remains unclear. Following stem cell administration, researchers have observed cell replacement, an increase in growth factors, and a reduction in inflammation. With a deeper understanding of the precise mechanism of stem cells, these therapies can be optimized in the clinic to afford the greatest therapeutic benefit. Recent studies have depicted a unique method of endogenous stem cell activation as a result of stem cell therapy. In both traumatic brain injury and stroke models, transplanted mesenchymal stromal cells (MSCs facilitated a pathway between the neurogenic niches of the brain and the damaged area through extracellular matrix remodeling. The biobridge pioneered by the MSCs was utilized by the endogenous stem cells, and these cells were able to travel to the damaged areas distal to the neurogenic niches, a feat unachievable without prior remodeling. These studies broaden our understanding of stem

  19. Spontaneous ischaemic stroke lesions in a dog brain: neuropathological characterisation and comparison to human ischaemic stroke

    DEFF Research Database (Denmark)

    Thomsen, Barbara Blicher; Gredal, Hanne; Wirenfeldt, Martin

    2017-01-01

    Background Dogs develop spontaneous ischaemic stroke with a clinical picture closely resembling human ischaemic stroke patients. Animal stroke models have been developed, but it has proved difficult to translate results obtained from such models into successful therapeutic strategies in human....../macrophages and astrocytes. Conclusions The neuropathological changes reported in the present study were similar to findings in human patients with ischaemic stroke. The dog with spontaneous ischaemic stroke is of interest as a complementary spontaneous animal model for further neuropathological studies....... stroke patients. In order to face this apparent translational gap within stroke research, dogs with ischaemic stroke constitute an opportunity to study the neuropathology of ischaemic stroke in an animal species. Case presentation A 7 years and 8 months old female neutered Rottweiler dog suffered...

  20. Post-stroke recovery: the role of activity-dependent release of brain-derived neurotrophic factor.

    Science.gov (United States)

    Berretta, Antonio; Tzeng, Yu-Chieh; Clarkson, Andrew N

    2014-11-01

    Stroke remains the leading cause of long-term disability with no pharmacological approaches available to limit the degree of damage or aid in recovery. Considerable effort has been made to minimize neuronal damage using neuroprotective compounds. However, attempts have so far failed to translate into the clinic. Brain-derived neurotrophic factor (BDNF) and its receptor tropomyosin-related kinase type B are actively produced throughout the brain and are involved in regulating neuronal activity and normal day-to-day function. Further, BDNF has been shown to play a role in both protection and recovery of functions after stroke. This review focuses on the endogenous release of BDNF as well as activity-induced (pharmacological and physical) elevation in BDNF, and the role this plays during both acute (hours to days) and subacute (days to weeks) periods after stroke. Exogenous administration has previously been shown not to cross the blood-brain barrier; therefore, we have focused this review on approaches that allow us to directly stimulate, using pharmacological therapies and mimetics, physical activity and potential drug delivery systems that can be used to administer BDNF. Finally, we also discuss the role of BDNF polymorphisms and the influence of epigenetic regulation of BDNF on post-stroke recovery.

  1. Stroke Rehabilitation

    Science.gov (United States)

    A stroke can cause lasting brain damage. People who survive a stroke need to relearn skills they lost because of ... them relearn those skills. The effects of a stroke depend on which area of the brain was ...

  2. Acute Psychosis Associated with Subcortical Stroke: Comparison between Basal Ganglia and Mid-Brain Lesions

    Directory of Open Access Journals (Sweden)

    Aaron McMurtray

    2014-01-01

    Full Text Available Acute onset of psychosis in an older or elderly individual without history of previous psychiatric disorders should prompt a thorough workup for neurologic causes of psychiatric symptoms. This report compares and contrasts clinical features of new onset of psychotic symptoms between two patients, one with an acute basal ganglia hemorrhagic stroke and another with an acute mid-brain ischemic stroke. Delusions and hallucinations due to basal ganglia lesions are theorized to develop as a result of frontal lobe dysfunction causing impairment of reality checking pathways in the brain, while visual hallucinations due to mid-brain lesions are theorized to develop due to dysregulation of inhibitory control of the ponto-geniculate-occipital system. Psychotic symptoms occurring due to stroke demonstrate varied clinical characteristics that depend on the location of the stroke within the brain. Treatment with antipsychotic medications may provide symptomatic relief.

  3. Plasticity in the developing brain: intellectual, language and academic functions in children with ischaemic perinatal stroke

    OpenAIRE

    Ballantyne, Angela O.; Spilkin, Amy M.; Hesselink, John; Trauner, Doris A.

    2008-01-01

    The developing brain has the capacity for a great deal of plasticity. A number of investigators have demonstrated that intellectual and language skills may be in the normal range in children following unilateral perinatal stroke. Questions have been raised, however, about whether these skills can be maintained at the same level as the brain matures. This study aimed to examine the stability of intellectual, academic and language functioning during development in children with perinatal stroke...

  4. Brain-machine interface in chronic stroke rehabilitation: a controlled study.

    Science.gov (United States)

    Ramos-Murguialday, Ander; Broetz, Doris; Rea, Massimiliano; Läer, Leonhard; Yilmaz, Ozge; Brasil, Fabricio L; Liberati, Giulia; Curado, Marco R; Garcia-Cossio, Eliana; Vyziotis, Alexandros; Cho, Woosang; Agostini, Manuel; Soares, Ernesto; Soekadar, Surjo; Caria, Andrea; Cohen, Leonardo G; Birbaumer, Niels

    2013-07-01

    Chronic stroke patients with severe hand weakness respond poorly to rehabilitation efforts. Here, we evaluated efficacy of daily brain-machine interface (BMI) training to increase the hypothesized beneficial effects of physiotherapy alone in patients with severe paresis in a double-blind sham-controlled design proof of concept study. Thirty-two chronic stroke patients with severe hand weakness were randomly assigned to 2 matched groups and participated in 17.8 ± 1.4 days of training rewarding desynchronization of ipsilesional oscillatory sensorimotor rhythms with contingent online movements of hand and arm orthoses (experimental group, n = 16). In the control group (sham group, n = 16), movements of the orthoses occurred randomly. Both groups received identical behavioral physiotherapy immediately following BMI training or the control intervention. Upper limb motor function scores, electromyography from arm and hand muscles, placebo-expectancy effects, and functional magnetic resonance imaging (fMRI) blood oxygenation level-dependent activity were assessed before and after intervention. A significant group × time interaction in upper limb (combined hand and modified arm) Fugl-Meyer assessment (cFMA) motor scores was found. cFMA scores improved more in the experimental than in the control group, presenting a significant improvement of cFMA scores (3.41 ± 0.563-point difference, p = 0.018) reflecting a clinically meaningful change from no activity to some in paretic muscles. cFMA improvements in the experimental group correlated with changes in fMRI laterality index and with paretic hand electromyography activity. Placebo-expectancy scores were comparable for both groups. The addition of BMI training to behaviorally oriented physiotherapy can be used to induce functional improvements in motor function in chronic stroke patients without residual finger movements and may open a new door in stroke neurorehabilitation. Copyright © 2013 American Neurological

  5. Breaking the Blood-Brain Barrier With Mannitol to Aid Stem Cell Therapeutics in the Chronic Stroke Brain.

    Science.gov (United States)

    Tajiri, Naoki; Lee, Jea Young; Acosta, Sandra; Sanberg, Paul R; Borlongan, Cesar V

    2016-01-01

    Blood-brain barrier (BBB) permeabilizers, such as mannitol, can facilitate peripherally delivered stem cells to exert therapeutic benefits on the stroke brain. Although this BBB permeation-aided stem cell therapy has been demonstrated in the acute stage of stroke, such BBB permeation in the chronic stage of the disease remains to be examined. Adult Sprague-Dawley rats initially received sham surgery or experimental stroke via the 1-h middle cerebral artery occlusion (MCAo) model. At 1 month after the MCAo surgery, stroke animals were randomly assigned to receive human umbilical cord stem cells only (2 million viable cells), mannitol only (1.1 mol/L mannitol at 4°C), combined human umbilical cord stem cells (200,000 viable cells) and mannitol (1.1 mol/L mannitol at 4°C), and vehicle (phosphate-buffered saline) only. Stroke animals that received human umbilical cord blood cells alone or combined human umbilical cord stem cells and mannitol exhibited significantly improved motor performance and significantly better brain cell survival in the peri-infarct area compared to stroke animals that received vehicle or mannitol alone, with mannitol treatment reducing the stem cell dose necessary to afford functional outcomes. Enhanced neurogenesis in the subventricular zone accompanied the combined treatment of human umbilical cord stem cells and mannitol. We showed that BBB permeation facilitates the therapeutic effects of a low dose of peripherally transplanted stem cells to effectively cause functional improvement and increase neurogenesis in chronic stroke.

  6. Ipsilateral motor pathways after stroke: implications for noninvasive brain stimulation

    Directory of Open Access Journals (Sweden)

    Lynley V Bradnam

    2013-05-01

    Full Text Available In humans the two cerebral hemispheres have essential roles in controlling the upper limb. The purpose of this article is to draw attention to the potential importance of ipsilateral descending pathways for functional recovery after stroke, and the use of noninvasive brain stimulation (NBS protocols of the contralesional primary motor cortex (M1. Conventionally NBS is used to suppress contralesional M1, and to attenuate transcallosal inhibition onto the ipsilesional M1. There has been little consideration of the fact that contralesional M1 suppression may also reduce excitability of ipsilateral descending pathways that may be important for paretic upper limb control for some patients. One such ipsilateral pathway is the cortico-reticulo-propriospinal pathway (CRPP. In this review we outline a neurophysiological model to explain how contralesional M1 may gain control of the paretic arm via the CRPP. We conclude that the relative importance of the CRPP for motor control in individual patients must be considered before using NBS to suppress contralesional M1. Neurophysiological, neuroimaging and clinical assessments can assist this decision making and facilitate the translation of NBS into the clinical setting.

  7. Stem cell-paved biobridges facilitate stem transplant and host brain cell interactions for stroke therapy.

    Science.gov (United States)

    Duncan, Kelsey; Gonzales-Portillo, Gabriel S; Acosta, Sandra A; Kaneko, Yuji; Borlongan, Cesar V; Tajiri, Naoki

    2015-10-14

    Distinguished by an infarct core encased within a penumbra, stroke remains a primary source of mortality within the United States. While our scientific knowledge regarding the pathology of stroke continues to improve, clinical treatment options for patients suffering from stroke are extremely limited. Tissue plasminogen activator (tPA) remains the sole FDA-approved drug proven to be helpful following stroke. However, due to the need to administer the drug within 4.5h of stroke onset its usefulness is constrained to less than 5% of all patients suffering from ischemic stroke. One experimental therapy for the treatment of stroke involves the utilization of stem cells. Stem cell transplantation has been linked to therapeutic benefit by means of cell replacement and release of growth factors; however the precise means by which this is accomplished has not yet been clearly delineated. Using a traumatic brain injury model, we recently demonstrated the ability of transplanted mesenchymal stromal cells (MSCs) to form a biobridge connecting the area of injury to the neurogenic niche within the brain. We hypothesize that MSCs may also have the capacity to create a similar biobridge following stroke; thereby forming a conduit between the neurogenic niche and the stroke core and peri-infarct area. We propose that this biobridge could assist and promote interaction of host brain cells with transplanted stem cells and offer more opportunities to enhance the effectiveness of stem cell therapy in stroke. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Prolonged drug-induced hypothermia in experimental stroke

    DEFF Research Database (Denmark)

    Johansen, Flemming Fryd; Jørgensen, Henrik Stig; Reith, Jakob

    2007-01-01

    In experimental and human stroke, hypothermia is strongly related to a favorable outcome. Previous attempts to manipulate the core temperature in focal cerebral ischemia have been based on mechanical cooling. The purpose of the study is to establish a model for long-term drug-induced hypothermia...

  9. Deep into the Brain: Artificial Intelligence in Stroke Imaging.

    Science.gov (United States)

    Lee, Eun-Jae; Kim, Yong-Hwan; Kim, Namkug; Kang, Dong-Wha

    2017-09-01

    Artificial intelligence (AI), a computer system aiming to mimic human intelligence, is gaining increasing interest and is being incorporated into many fields, including medicine. Stroke medicine is one such area of application of AI, for improving the accuracy of diagnosis and the quality of patient care. For stroke management, adequate analysis of stroke imaging is crucial. Recently, AI techniques have been applied to decipher the data from stroke imaging and have demonstrated some promising results. In the very near future, such AI techniques may play a pivotal role in determining the therapeutic methods and predicting the prognosis for stroke patients in an individualized manner. In this review, we offer a glimpse at the use of AI in stroke imaging, specifically focusing on its technical principles, clinical application, and future perspectives.

  10. Clinical course of brain stroke in the persons exposed to ionizing radiation under the production conditions

    International Nuclear Information System (INIS)

    Bouchmanov, A.

    2000-01-01

    The purpose was to study the risk factors and clinical course of brain strokes in professionally exposed workers being employed in plutonium production in comparison with a control group. The method and materials of study -clinical supervision and clinical database creation on 162 cases of brain stroke (128 males and 34 females) developed among professionally exposed workers. Age of patient varied from 21 to 68 years (in average -51.6 y.). The control group consisted of patients with the same diagnosis, worked on the same enterprise, but non-exposed to radiation. Data on the totally accumulated dose of external gamma radiation were received on the base of the individual dosimeters (from 0.1 cSv to 52 cSv, in average about 13 cSv); the plutonium-239 body content was estimated accordingly to the level of urine radionuclide excretion (from 0.4 kBq to 1.6 kBq, in average about 0.33 kBq). Muscle's hypertinsion and pathological great-toe reflexes in paretic legs and hands, hemianopsia, impressive and ataxic aphasia prevailed in the patients with ischemic brain strokes in system of internal carotid artery, exposed to radiation. The changes of muscle's tension, ataxia and nystagmus were marked more often in the professionals with ischemic brain strokes in system of vertebrobasilar artery. The illness proceeded more easy and with smaller frequency of frustration of consciousness and algesthesia, irrespective of a type ischemic brain strokes in the people exposed to ionizing radiation, than in patients of non-irradiated group. It was found that the arterial hypertension appeared to be the main risk factor for the brain stroke in both groups of patients (in 81.48% and 91.15% of cases). There was no marked differences in significance of risk factors and in main clinical parameters of various types of ischemic brain strokes among the patients professionally exposed to radiation in comparison with a control group. (author)

  11. Arginine-Vasopressin Receptor Blocker Conivaptan Reduces Brain Edema and Blood-Brain Barrier Disruption after Experimental Stroke in Mice.

    Directory of Open Access Journals (Sweden)

    Emil Zeynalov

    Full Text Available Stroke is a major cause of morbidity and mortality. Stroke is complicated by brain edema and blood-brain barrier (BBB disruption, and is often accompanied by increased release of arginine-vasopressin (AVP. AVP acts through V1a and V2 receptors to trigger hyponatremia, vasospasm, and platelet aggregation which can exacerbate brain edema. The AVP receptor blockers conivaptan (V1a and V2 and tolvaptan (V2 are used to correct hyponatremia, but their effect on post-ischemic brain edema and BBB disruption remains to be elucidated. Therefore, we conducted this study to investigate if these drugs can prevent brain edema and BBB disruption in mice after stroke.Experimental mice underwent the filament model of middle cerebral artery occlusion (MCAO with reperfusion. Mice were treated with conivaptan, tolvaptan, or vehicle. Treatments were initiated immediately at reperfusion and administered IV (conivaptan or orally (tolvaptan for 48 hours. Physiological variables, neurological deficit scores (NDS, plasma and urine sodium and osmolality were recorded. Brain water content (BWC and Evans Blue (EB extravasation index were evaluated at the end point.Both conivaptan and tolvaptan produced aquaresis as indicated by changes in plasma and urine sodium levels. However plasma and urine osmolality was changed only by conivaptan. Unlike tolvaptan, conivaptan improved NDS and reduced BWC in the ipsilateral hemisphere: from 81.66 ± 0.43% (vehicle to 78.28 ± 0.48% (conivaptan, 0.2 mg, p < 0.05 vs vehicle. Conivaptan also attenuated the EB extravasation from 1.22 ± 0.08 (vehicle to 1.01 ± 0.02 (conivaptan, 0.2 mg, p < 0.05.Continuous IV infusion with conivaptan for 48 hours after experimental stroke reduces brain edema, and BBB disruption. Conivaptan but not tolvaptan may potentially be used in patients to prevent brain edema after stroke.

  12. The sigma-1 receptor enhances brain plasticity and functional recovery after experimental stroke

    DEFF Research Database (Denmark)

    Ruscher, Karsten; Shamloo, Mehrdad; Rickhag, Karl Mattias

    2011-01-01

    Stroke leads to brain damage with subsequent slow and incomplete recovery of lost brain functions. Enriched housing of stroke-injured rats provides multi-modal sensorimotor stimulation, which improves recovery, although the specific mechanisms involved have not been identified. In rats housed......)piperazine dihydrochloride, an agonist of the sigma-1 receptor, starting two days after injury, enhanced the recovery of lost sensorimotor function without decreasing infarct size. The sigma-1 receptor was found in the galactocerebroside enriched membrane microdomains of reactive astrocytes and in neurons. Sigma-1 receptor...... of biomolecules required for brain repair, thereby stimulating brain plasticity. Pharmacological targeting of the sigma-1 receptor provides new opportunities for stroke treatment beyond the therapeutic window of neuroprotection....

  13. Association Between Brain-Derived Neurotrophic Factor Genotype and Upper Extremity Motor Outcome After Stroke.

    Science.gov (United States)

    Chang, Won Hyuk; Park, Eunhee; Lee, Jungsoo; Lee, Ahee; Kim, Yun-Hee

    2017-06-01

    The identification of intrinsic factors for predicting upper extremity motor outcome could aid the design of individualized treatment plans in stroke rehabilitation. The aim of this study was to identify prognostic factors, including intrinsic genetic factors, for upper extremity motor outcome in patients with subacute stroke. A total of 97 patients with subacute stroke were enrolled. Upper limb motor impairment was scored according to the upper limb of Fugl-Meyer assessment score at 3 months after stroke. The prediction of upper extremity motor outcome at 3 months was modeled using various factors that could potentially influence this impairment, including patient characteristics, baseline upper extremity motor impairment, functional and structural integrity of the corticospinal tract, and brain-derived neurotrophic factor genotype. Multivariate ordinal logistic regression models were used to identify the significance of each factor. The independent predictors of motor outcome at 3 months were baseline upper extremity motor impairment, age, stroke type, and corticospinal tract functional integrity in all stroke patients. However, in the group with severe motor impairment at baseline (upper limb score of Fugl-Meyer assessment stroke. Brain-derived neurotrophic factor genotype may be a potentially useful predictor of upper extremity motor outcome in patients with subacute stroke with severe baseline motor involvement. © 2017 American Heart Association, Inc.

  14. Exercise in the Early Stage after Stroke Enhances Hippocampal Brain-Derived Neurotrophic Factor Expression and Memory Function Recovery.

    Science.gov (United States)

    Himi, Naoyuki; Takahashi, Hisashi; Okabe, Naohiko; Nakamura, Emi; Shiromoto, Takashi; Narita, Kazuhiko; Koga, Tomoshige; Miyamoto, Osamu

    2016-12-01

    Exercise in the early stage after stroke onset has been shown to facilitate the recovery from physical dysfunction. However, the mechanism of recovery has not been clarified. In this study, the effect of exercise on spatial memory function recovery in the early stage was shown, and the mechanism of recovery was discussed using a rat model of brain embolism. Intra-arterial microsphere (MS) injection induced small emboli in the rat brain. Treadmill exercise was started at 24 hours (early group) or 8 days (late group) after MS injection. The non-exercise (NE) and sham-operated groups were included as controls. Memory function was evaluated by the Morris water maze test, and hippocampal levels of brain-derived neurotrophic factor (BDNF) were measured by enzyme-linked immunosorbent assays. To further investigate the effect of BDNF on memory function, BDNF was continuously infused into the hippocampus via implantable osmotic pumps in the early or late stage after stroke. Memory function significantly improved only in the early group compared with the late and the NE groups, although hippocampal BDNF concentrations were temporarily elevated after exercise in both the early and the late groups. Rats infused with BDNF in the early stage exhibited significant memory function recovery; however, rats that received BDNF infusion in the late stage showed no improvement. Exercise elevates hippocampal BDNF levels in the early stage after cerebral embolism, and this event facilitates memory function recovery. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  15. Acupuncture stimulation induces neurogenesis in adult brain.

    Science.gov (United States)

    Nam, Min-Ho; Ahn, Kwang Seok; Choi, Seung-Hoon

    2013-01-01

    The discovery of adult neurogenesis was a turning point in the field of neuroscience. Adult neurogenesis offers an enormous possibility to open a new therapeutic paradigm of neurodegenerative diseases and stroke. Recently, several studies suggested that acupuncture may enhance adult neurogenesis. Acupuncture has long been an important treatment for brain diseases in the East Asia. The scientific mechanisms of acupuncture treatment for the diseases, such as Alzheimer's disease, Parkinson's disease, and stroke, have not been clarified yet; however, the neurogenic effect of acupuncture can be a possible reason. Here, we have reviewed the studies on the effect of stimulation at various acupoints for neurogenesis, such as ST36 and GV20. The suggested mechanisms are also discussed including upregulation of brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, basic fibroblast growth factor and neuropeptide Y, and activation of the function of primo vascular system. © 2013 Elsevier Inc. All rights reserved.

  16. Synaptic inputs from stroke-injured brain to grafted human stem cell-derived neurons activated by sensory stimuli.

    Science.gov (United States)

    Tornero, Daniel; Tsupykov, Oleg; Granmo, Marcus; Rodriguez, Cristina; Grønning-Hansen, Marita; Thelin, Jonas; Smozhanik, Ekaterina; Laterza, Cecilia; Wattananit, Somsak; Ge, Ruimin; Tatarishvili, Jemal; Grealish, Shane; Brüstle, Oliver; Skibo, Galina; Parmar, Malin; Schouenborg, Jens; Lindvall, Olle; Kokaia, Zaal

    2017-03-01

    Transplanted neurons derived from stem cells have been proposed to improve function in animal models of human disease by various mechanisms such as neuronal replacement. However, whether the grafted neurons receive functional synaptic inputs from the recipient's brain and integrate into host neural circuitry is unknown. Here we studied the synaptic inputs from the host brain to grafted cortical neurons derived from human induced pluripotent stem cells after transplantation into stroke-injured rat cerebral cortex. Using the rabies virus-based trans-synaptic tracing method and immunoelectron microscopy, we demonstrate that the grafted neurons receive direct synaptic inputs from neurons in different host brain areas located in a pattern similar to that of neurons projecting to the corresponding endogenous cortical neurons in the intact brain. Electrophysiological in vivo recordings from the cortical implants show that physiological sensory stimuli, i.e. cutaneous stimulation of nose and paw, can activate or inhibit spontaneous activity in grafted neurons, indicating that at least some of the afferent inputs are functional. In agreement, we find using patch-clamp recordings that a portion of grafted neurons respond to photostimulation of virally transfected, channelrhodopsin-2-expressing thalamo-cortical axons in acute brain slices. The present study demonstrates, for the first time, that the host brain regulates the activity of grafted neurons, providing strong evidence that transplanted human induced pluripotent stem cell-derived cortical neurons can become incorporated into injured cortical circuitry. Our findings support the idea that these neurons could contribute to functional recovery in stroke and other conditions causing neuronal loss in cerebral cortex. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. The effect of ultrasound on thromboembolic model of brain stroke in rat

    Directory of Open Access Journals (Sweden)

    Shabanzadeh A

    2007-08-01

    Full Text Available Background: Ultrasound (US has been used in neuroprotection after cerebral ischemia; however, its use is controversial. Application of US in combination with fibrinolytic agents may improve fibrinolytic effects. In this study the effects of US, alone or in combination with tissue plasminogen activator (tPA, on brain ischemic injury were examined and we studied whether US is protective in the brain injured by ischemia under normothermic conditions. Methods: We performed two studies. In the first study, rectal and brain temperatures were compared. In the second study, we studied whether US alone or in combination with tPA is neuroprotective in thromboembolic stroke. To induce focal cerebral ischemia, a clot was formed in a catheter. Once the clot had formed, the catheter was advanced 17 mm in the internal carotid artery until its tip was 1-2 mm away from the origin of the middle cerebral artery (MCA. The preformed clot in the catheter was then injected, and the catheter was removed. The wound was then closed and the infarction volume, edema and neurological deficits were measured after MCA occlusion. Results: The temperature in the brain was approximately 0.50 ºC lower than the rectal temperature. In the control, US+low tPA, low tPA, US+high tPA and, high tPA groups, the infarct volume (% was 34.56±4.16, 17.09±6.72, 21.25±7.8, 13.5±10.72 and 20.61±6.17 (mean ±SD at 48 h after MCA occlusion, respectively. The results indicate that US alone reduces the infarct volume by 30% compared to that of the control group (P<0.05. US improved neurological deficits and reduced brain edema significantly (p<0.05. Conclusions: This study indicate that US appears to have a protective effect, alone and in combination with tPA, in an embolic model of stroke.

  18. Sexual dysfunction in male stroke patients: correlation between brain lesions and sexual function.

    Science.gov (United States)

    Jung, Jea-Hun; Kam, Sung-Chul; Choi, Sae-Min; Jae, Sung-Uk; Lee, Seung-Hyun; Hyun, Jae-Seog

    2008-01-01

    To identify the sexual function of, and effect of the location of brain lesions on sexual function in, stroke patients. We conducted a survey on 109 stroke patients (64.93 +/- 8.81 years) and 109 age-matched controls (64.69 +/- 8.85 years). We used a questionnaire that included the five-item version of the International Index of Erectile Function (IIEF-5) and questions about changes in sexual desire, ejaculatory function, and sexual satisfaction after a stroke. We analyzed the correlation between the results of the questionnaire and the locations of brain lesions. Erectile function was significantly decreased in the stroke patient group (IIEF-5, 5.89 +/- 7.08) compared with the control group (IIEF-5, 10.67 +/- 7.10). In most patients, the frequency of intercourse and sexual desire decreased after stroke, and an ejaculation disorder accompanied intercourse, but fear regarding intercourse was not severe. A lack of sexual desire was the largest cause (59.4%) of an absence of sexual intercourse. In cases with lesions in the right cerebellum and the left basal ganglia, a significant ejaculation disorder and decrease of sexual desire were more likely to occur, respectively. The sexual desire, erectile function, and ejaculatory function were impaired after stroke. A lack of sexual desire was the major cause of an absence of sexual intercourse. The specific locations of the stroke lesions, such as the left basal ganglia and right cerebellum, might be associated with sexual desire and ejaculation disorder, respectively.

  19. Non-invasive brain stimulation: an interventional tool for enhancing behavioral training after stroke

    Directory of Open Access Journals (Sweden)

    Maximilian Jonas Wessel

    2015-05-01

    Full Text Available Stroke is the leading cause of disability among adults. Motor deficit is the most common impairment after stroke. Especially, deficits in fine motor skills impair numerous activities of daily life. Re-acquisition of motor skills resulting in improved or more accurate motor performance is paramount to regain function, and is the basis of behavioral motor therapy after stroke. Within the past years, there has been a rapid technological and methodological development in neuroimaging leading to a significant progress in the understanding of the neural substrates that underlie motor skill acquisition and functional recovery in stroke patients. Based on this and the development of novel non-invasive brain stimulation techniques, new adjuvant interventional approaches that augment the response to behavioral training have been proposed. Transcranial direct current (tDCS, transcranial magnetic (TMS and paired associative (PAS stimulation are noninvasive brain stimulation techniques that can modulate cortical excitability, neuronal plasticity and interact with learning and memory in both healthy individuals and stroke patients. These techniques can enhance the effect of practice and facilitate the retention of tasks that mimic daily life activities. The purpose of the present review is to provide a comprehensive overview of neuroplastic phenomena in the motor system during learning of a motor skill, recovery after brain injury, and of interventional strategies to enhance the beneficial effects of customarily used neurorehabilitation after stroke.

  20. [Ischemic stroke induced by a left atrial myxoma].

    Science.gov (United States)

    Hatayama, Sayaka; Ogata, Toshiyasu; Okawa, Masakazu; Higashi, Toshio; Inoue, Tooru; Takano, Koichi; Minematsu, Noritoshi; Tashiro, Tadashi; Sakata, Noriyuki

    2012-10-01

    We reported a case of ischemic stroke induced by a left atrial myxoma. A 76-year-old man was found unconscious and transferred to the emergency ward in our hospital. He experienced consciousness disturbance, motor dominant aphasia, and severe right hemiparesis. His neurological and radiological findings indicated that he had ischemic stroke and was eligible to undergo intravenous thrombolysis. Alteplase was administrated 155 min after the onset of stroke. Intracerebral hemorrhage was not seen 24h after thrombolysis. A tumor in the left atrium was detected on transthoracic echocardiography, and this finding suggested that the tumor was a myxoma. Although cardiac surgery was scheduled, hemorrhagic transformation was found on day 11, which made us postpone the surgery. After the hemorrhage was disappeared, the tumor was resected by open-heart surgery and it was confirmed to be a myxoma. Neither his neurological symptom nor intracerebral hemorrhage was not deteriorated after the operation. Thrombolytic treatment seemed a safe option for ischemic stroke caused by left atrial myxoma. However, we should carefully monitor the extent of anticoagulation therapy because hemorrhagic transformation might alter the timing of surgery for tumor resection.

  1. Brain imaging and cognitive predictors of stroke and Alzheimer disease in the Framingham Heart Study.

    Science.gov (United States)

    Weinstein, Galit; Beiser, Alexa S; Decarli, Charles; Au, Rhoda; Wolf, Philip A; Seshadri, Sudha

    2013-10-01

    Exposure to vascular risk factors has a gradual deleterious effect on brain MRI and cognitive measures. We explored whether a pattern of these measures exists that predicts stroke and Alzheimer disease (AD) risk. A cognitive battery was administered to 1679 dementia and stroke-free Framingham offspring (age, >55 years; mean, 65.7±7.0) between 1999 and 2004; participants were also free of other neurological conditions that could affect cognition and >90% also had brain MRI examination. We related cognitive and MRI measures to risks of incident stroke and AD ≤10 years of follow-up. As a secondary analysis, we explored these associations in The Framingham Heart Study original cohort (mean age, 67.5±7.3 and 84.8±3.3 years at the cognitive assessment and MRI examination, respectively). A total of 55 Offspring participants sustained strokes and 31 developed AD. Offspring who scored stroke (hazard ratio [HR], 2.27; 95% confidence interval [CI], 1.06-4.85) and AD (HR, 3.60; 95% CI, 1.52-8.52); additional cognitive tests also predicted AD. Participants with low (20 percentile) white matter hyperintensity volume had a higher risk of stroke (HR, 1.97; 95% CI, 1.03-3.77 and HR, 2.74; 95% CI, 1.51-5.00, respectively) but not AD. Hippocampal volume at the bottom quintile predicted AD in the offspring and original cohorts (HR, 4.41; 95% CI, 2.00-9.72 and HR, 2.37; 95% CI, 1.12-5.00, respectively). A stepwise increase in stroke risk was apparent with increasing numbers of these cognitive and imaging markers. Specific patterns of cognitive and brain structural measures observed even in early aging predict stroke risk and may serve as biomarkers for risk prediction.

  2. Automated Quantification of Stroke Damage on Brain Computed Tomography Scans: e-ASPECTS

    Directory of Open Access Journals (Sweden)

    James Hampton-Till

    2015-08-01

    Full Text Available Emergency radiological diagnosis of acute ischaemic stroke requires the accurate detection and appropriate interpretation of relevant imaging findings. Non-contrast computed tomography (CT provides fast and low-cost assessment of the early signs of ischaemia and is the most widely used diagnostic modality for acute stroke. The Alberta Stroke Program Early CT Score (ASPECTS is a quantitative and clinically validated method to measure the extent of ischaemic signs on brain CT scans. The CE-marked electronic-ASPECTS (e-ASPECTS software automates the ASPECTS score. Anglia Ruskin Clinical Trials Unit (ARCTU independently carried out a clinical investigation of the e-ASPECTS software, an automated scoring system which can be integrated into the diagnostic pathway of an acute ischaemic stroke patient, thereby assisting the physician with expert interpretation of the brain CT scan. Here we describe a literature review of the clinical importance of reliable assessment of early ischaemic signs on plain CT scans, and of technologies automating these processed scoring systems in ischaemic stroke on CT scans focusing on the e-ASPECTS software. To be suitable for critical appraisal in this evaluation, the published studies needed a sample size of a minimum of 10 cases. All randomised studies were screened and data deemed relevant to demonstration of performance of ASPECTS were appraised. The literature review focused on three domains: i interpretation of brain CT scans of stroke patients, ii the application of the ASPECTS score in ischaemic stroke, and iii automation of brain CT analysis. Finally, the appraised references are discussed in the context of the clinical impact of e-ASPECTS and the expected performance, which will be independently evaluated by a non-inferiority study conducted by the ARCTU.

  3. Cerebellar stroke presenting with isolated dizziness: Brain MRI in 136 patients.

    Science.gov (United States)

    Perloff, Michael D; Patel, Nimesh S; Kase, Carlos S; Oza, Anuja U; Voetsch, Barbara; Romero, Jose R

    2017-11-01

    To evaluate occurrence of cerebellar stroke in Emergency Department (ED) presentations of isolated dizziness (dizziness with a normal exam and negative neurological review of systems). A 5-year retrospective study of ED patients presenting with a chief complaint of "dizziness or vertigo", without other symptoms or signs in narrative history or on exam to suggest a central nervous system lesion, and work-up included a brain MRI within 48h. Patients with symptoms commonly peripheral in etiology (nystagmus, tinnitus, gait instability, etc.) were included in the study. Patient demographics, stroke risk factors, and gait assessments were recorded. One hundred and thirty-six patients, who had a brain MRI for isolated dizziness, were included. There was a low correlation of gait assessment between ED physician and Neurologist (49 patients, Spearman's correlation r 2 =0.17). Based on MRI DWI sequence, 3.7% (5/136 patients) had acute cerebellar strokes, limited to or including, the medial posterior inferior cerebellar artery vascular territory. In the 5 cerebellar stroke patients, mean age, body mass index (BMI), hemoglobin A1c, gender distribution, and prevalence of hypertension were similar to the non-cerebellar stroke patient group. Mean LDL/HDL ratio was 3.63±0.80 and smoking prevalence was 80% in the cerebellar stroke group compared to 2.43±0.79 and 22% (respectively, p values<0.01) in the non-cerebellar stroke group. Though there was preselection bias for stroke risk factors, our study suggests an important proportion of cerebellar stroke among ED patients with isolated dizziness, considering how common this complaint is. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Emerging Molecular Targets for Brain Repair after Stroke

    Directory of Open Access Journals (Sweden)

    Jerzy Krupinski

    2013-01-01

    Full Text Available The field of neuroprotection generated consistent preclinical findings of mechanisms of cell death but these failed to be translated into clinics. The approaches that combine the modulation of the inhibitory environment together with the promotion of intrinsic axonal outgrowth needs further work before combined therapeutic strategies will be transferable to clinic trials. It is likely that only when some answers have been found to these issues will our therapeutic efforts meet our expectations. Stroke is a clinically heterogeneous disease and combinatorial treatments require much greater work in pharmacological and toxicological testing. Advances in genetics and results of the Whole Human Genome Project (HGP provided new unknown information in relation to stroke. Genetic factors are not the only determinants of responses to some diseases. It was recognized early on that “epigenetic” factors were major players in the aetiology and progression of many diseases like stroke. The major players are microRNAs that represent the best-characterized subclass of noncoding RNAs. Epigenetic mechanisms convert environmental conditions and physiological stresses into long-term changes in gene expression and translation. Epigenetics in stroke are in their infancy but offer great promise for better understanding of stroke pathology and the potential viability of new strategies for its treatment.

  5. Brain perfusion-CT in acute stroke patients

    International Nuclear Information System (INIS)

    Andreev, T.; Totsev, N.; Tzvetanov, P.

    2013-01-01

    Since 1979 when Grodfrey Hounsfield and Allan Corman introduced the computed tomography new generations of CT were developed that improved the special resolution and time of acquisition. The role of neuro-imaging in the evaluation of acute stroke has changed dramatically in the past decade. Previously, neuro-imaging was used in this set-ting to provide anatomic imaging that indicated the presence or absence of acute cerebral ischemia and excluded lesions that produce symptoms or signs mimicking those of stroke, such as hemorrhage and neoplasms. More recently, the introduction of thrombolysis has changed the goals of neuro-imaging from providing solely anatomic information to providing physiologic information that could help to determine which patients might benefit from therapy. In particular, significant emphasis has been placed on the delineation of the ischemic penumbra, also called tissue at risk. Modem CT survey, consisting of three indissociable elements; noncontrast CT (NCT) of course, perfusion-CT (PCT) and CT-angiography (CTA), fulfill all the requirements for hyperacute stroke imaging. CTA can define the occlusion site, depict arterial dissection, grade collateral blood flow, and characterize atherosclerotic disease, whereas PCT accurately defines the infarct core and the ischemic penumbra. CT offers a number of practical advantages over other cerebral perfusion imaging methods, including its wide availability. Using PCT and CTA to define new individualized strategies for acute reperfusion will allow more acute stroke patients to benefit from thrombolytic therapy. Key words: Stroke. Penumbra. Computed Tomography. Perfusion-CT. CT Angiography. Outcome

  6. Combination cell therapy with mesenchymal stem cells and neural stem cells for brain stroke in rats.

    Science.gov (United States)

    Hosseini, Seyed Mojtaba; Farahmandnia, Mohammad; Razi, Zahra; Delavari, Somayeh; Shakibajahromi, Benafsheh; Sarvestani, Fatemeh Sabet; Kazemi, Sepehr; Semsar, Maryam

    2015-05-01

    Brain stroke is the second most important events that lead to disability and morbidity these days. Although, stroke is important, there is no treatment for curing this problem. Nowadays, cell therapy has opened a new window for treating central nervous system disease. In some previous studies the Mesenchymal stem cells and neural stem cells. In this study, we have designed an experiment to assess the combination cell therapy (Mesenchymal and Neural stem cells) effects on brain stroke. The Mesenchymal stem cells were isolated from adult rat bone marrow and the neural stem cells were isolated from ganglion eminence of rat embryo 14 days. The Mesenchymal stem cells were injected 1 day after middle cerebral artery occlusion (MCAO) and the neural stem cells transplanted 7 day after MCAO. After 28 days, the neurological outcomes and brain lesion volumes were evaluated. Also, the activity of Caspase 3 was assessed in different groups. The group which received combination cell therapy had better neurological examination and less brain lesion. Also the combination cell therapy group had the least Caspase 3 activity among the groups. The combination cell therapy is more effective than Mesenchymal stem cell therapy and neural stem cell therapy separately in treating the brain stroke in rats.

  7. Erythropoietin reduces brain injury after intracerebral hemorrhagic stroke in rats.

    Science.gov (United States)

    Yu, Zhen; Tang, Ling; Chen, Lifen; Li, Jinfang; Wu, Wanfu; Hu, Changlin

    2013-11-01

    Erythropoietin (EPO) has been shown to be neuroprotective in various models of neuronal injury. The aim of the present study was to investigate the beneficial effect of recombinant human EPO (rhEPO) following intracerebral hemorrhage (ICH) and the underlying molecular and cellular mechanisms. ICH was induced using autologous blood injection in adult rats. rhEPO (5000 IU/kg) or vehicle was administered to rats with ICH 2 h following surgery and every 24 h for 1 or 3 days. To study the involvement of the PI3K signaling pathway in the rhEPO‑mediated effect, the PI3K inhibitor wortmannin (15 µg/kg), was intravenously administered to rats with ICH 90 min prior to rhEPO treatment. Brain edema was measured 3 days following ICH and behavioral outcomes were measured at 1, 7, 14, 21 and 28 days following ICH using the modified neurological severity score (mNSS) and the corner turn test. Proinflammatory cytokines, including tumor necrosis factor (TNF)‑α, interleukin (IL)-1β and IL-6, in the ipsilateral striatum were analyzed using an enzyme-linked immunosorbent assay 24 h following ICH. Neuronal apoptosis in the perihematomal area was determined by NeuN and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) double-staining. The results showed that rhEPO treatment reversed ICH, increased brain water content, upregulated proinflammatory cytokines, neuronal loss and apoptosis in the perihematomal area and rescued behavioral deficits in injured rats. Inhibiting the PI3K pathway with wortmannin abolished the rhEPO‑mediated neuroprotective effects. Moreover, western blot analysis showed that rhEPO induced the upregulation of Akt phosphorylation and downregulation of glycogen synthase kinase (GSK)‑3β phosphorylation, which were reversed by pretreatment with wortmannin, indicating the involvement of PI3K signaling in rhEPO-mediated anti-apoptotic and anti-inflammatory effects following ICH. In conclusion, these results suggested that rhEPO may exert its

  8. Matrix Metalloproteinases and Blood-Brain Barrier Disruption in Acute Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Shaheen E. Lakhan

    2013-04-01

    Full Text Available Ischemic stroke continues to be one of the most challenging diseases in translational neurology. Tissue plasminogen activator (tPA remains the only approved treatment for acute ischemic stroke, but its use is limited to the first hours after stroke onset due to an increased risk of hemorrhagic transformation over time resulting in enhanced brain injury. In this review we discuss the role of matrix metalloproteinases (MMPs in blood-brain barrier (BBB disruption as a consequence of ischemic stroke. MMP-9 in particular appears to play an important role in tPA-associated hemorrhagic complications. Reactive oxygen species can enhance the effects of tPA on MMP activation through the loss of caveolin-1 (cav-1, a protein encoded in the cav-1 gene that serves as a critical determinant of BBB permeability. This review provides an overview of MMPs’ role in BBB breakdown during acute ischemic stroke. The possible role of MMPs in combination treatment of acute ischemic stroke is also examined.

  9. Post-stroke acquired amusia: A comparison between right- and left-brain hemispheric damages.

    Science.gov (United States)

    Jafari, Zahra; Esmaili, Mahdiye; Delbari, Ahmad; Mehrpour, Masoud; Mohajerani, Majid H

    2017-01-01

    Although extensive research has been published about the emotional consequences of stroke, most studies have focused on emotional words, speech prosody, voices, or facial expressions. The emotional processing of musical excerpts following stroke has been relatively unexplored. The present study was conducted to investigate the effects of chronic stroke on the recognition of basic emotions in music. Seventy persons, including 25 normal controls (NC), 25 persons with right brain damage (RBD) from stroke, and 20 persons with left brain damage (LBD) from stroke between the ages of 31-71 years were studied. The Musical Emotional Bursts (MEB) test, which consists of a set of short musical pieces expressing basic emotional states (happiness, sadness, and fear) and neutrality, was used to test musical emotional perception. Both stroke groups were significantly poorer than normal controls for the MEB total score and its subtests (p amusia with greater severity in RBD than LBD. These results supported the "valence hypothesis" of right hemisphere dominance in processing negative emotions.

  10. Paediatric stroke

    African Journals Online (AJOL)

    2011-04-02

    Apr 2, 2011 ... Ischemic Stroke Registry yielded an incidence of 3.3 cases per 100 000 children per year, of ... Neonatal stroke. The newborn period confers the highest risk period for childhood ischaemic stroke. Focal patterns of ischaemic brain injury to the perinatal brain are .... family history of young stroke/ thrombosis.

  11. Applications of Brain-Machine Interface Systems in Stroke Recovery and Rehabilitation.

    Science.gov (United States)

    Venkatakrishnan, Anusha; Francisco, Gerard E; Contreras-Vidal, Jose L

    2014-06-01

    Stroke is a leading cause of disability, significantly impacting the quality of life (QOL) in survivors, and rehabilitation remains the mainstay of treatment in these patients. Recent engineering and technological advances such as brain-machine interfaces (BMI) and robotic rehabilitative devices are promising to enhance stroke neu-rorehabilitation, to accelerate functional recovery and improve QOL. This review discusses the recent applications of BMI and robotic-assisted rehabilitation in stroke patients. We present the framework for integrated BMI and robotic-assisted therapies, and discuss their potential therapeutic, assistive and diagnostic functions in stroke rehabilitation. Finally, we conclude with an outlook on the potential challenges and future directions of these neurotechnologies, and their impact on clinical rehabilitation.

  12. Implications of MMP9 for Blood Brain Barrier Disruption And Hemorrhagic Transformation Following Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Renee Jade Turner

    2016-03-01

    Full Text Available Numerous studies have documented increases in matrix metalloproteinases (MMPs, specifically MMP-9 levels following stroke, with such perturbations associated with disruption of the blood brain barrier (BBB, increased risk of hemorrhagic complications and worsened outcome. Despite this, controversy remains as to which cells release MMP-9 at the normal and pathological BBB, with even less clarity in the context of stroke. This may be further complicated by the influence of tissue plasminogen activator (tPA treatment. The aim of the present review is to examine the relationship between neutrophils, MMP-9 and tPA following ischemic stroke to elucidate which cells are responsible for the increases in MMP-9 and resultant barrier changes and hemorrhage observed following stroke.

  13. Real-time monitoring of ischemic and contralateral brain pO2 during stroke by variable length multisite resonators.

    Science.gov (United States)

    Hou, Huagang; Li, Hongbin; Dong, Ruhong; Khan, Nadeem; Swartz, Harold

    2014-06-01

    Electron paramagnetic resonance (EPR) oximetry using variable length multi-probe implantable resonator (IR), was used to investigate the temporal changes in the ischemic and contralateral brain pO2 during stroke in rats. The EPR signal to noise ratio (S/N) of the IR with four sensor loops at a depth of up to 11 mm were compared with direct implantation of lithium phthalocyanine (LiPc, oximetry probe) deposits in vitro. These IRs were used to follow the temporal changes in pO2 at two sites in each hemisphere during ischemia induced by left middle cerebral artery occlusion (MCAO) in rats breathing 30% O2 or 100% O2. The S/N ratios of the IRs were significantly greater than the LiPc deposits. A similar pO2 at two sites in each hemisphere prior to the onset of ischemia was observed in rats breathing 30% O2. However, a significant decline in the pO2 of the left cortex and striatum occurred during ischemia, but no change in the pO2 of the contralateral brain was observed. A significant increase in the pO2 of only the contralateral non-ischemic brain was observed in the rats breathing 100% O2. No significant difference in the infarct volume was evident between the animals breathing 30% O2 or 100% O2 during ischemia. EPR oximetry with IRs can repeatedly assess temporal changes in the brain pO2 at four sites simultaneously during stroke. This oximetry approach can be used to test and develop interventions to rescue ischemic tissue by modulating cerebral pO2 during stroke. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Role of Transporters in Central Nervous System Drug Delivery and Blood-Brain Barrier Protection: Relevance to Treatment of Stroke

    Directory of Open Access Journals (Sweden)

    Hrvoje Brzica

    2017-03-01

    Full Text Available Ischemic stroke is a leading cause of morbidity and mortality in the United States. The only approved pharmacologic treatment for ischemic stroke is thrombolysis via recombinant tissue plasminogen activator (r-tPA. A short therapeutic window and serious adverse events (ie, hemorrhage, excitotoxicity greatly limit r-tPA therapy, which indicates an essential need to develop novel stroke treatment paradigms. Transporters expressed at the blood-brain barrier (BBB provide a significant opportunity to advance stroke therapy via central nervous system delivery of drugs that have neuroprotective properties. Examples of such transporters include organic anion–transporting polypeptides (Oatps and organic cation transporters (Octs. In addition, multidrug resistance proteins (Mrps are transporter targets in brain microvascular endothelial cells that can be exploited to preserve BBB integrity in the setting of stroke. Here, we review current knowledge on stroke pharmacotherapy and demonstrate how endogenous BBB transporters can be targeted for improvement of ischemic stroke treatment.

  15. Association of reduced folate carrier-1 (RFC-1) polymorphisms with ischemic stroke and silent brain infarction.

    Science.gov (United States)

    Cho, Yunkyung; Kim, Jung O; Lee, Jeong Han; Park, Hye Mi; Jeon, Young Joo; Oh, Seung Hun; Bae, Jinkun; Park, Young Seok; Kim, Ok Joon; Kim, Nam Keun

    2015-01-01

    Stroke is the second leading cause of death in the world and in South Korea. Ischemic stroke and silent brain infarction (SBI) are complex, multifactorial diseases influenced by multiple genetic and environmental factors. Moderately elevated plasma homocysteine levels are a major risk factor for vascular diseases, including stroke and SBI. Folate and vitamin B12 are important regulators of homocysteine metabolism. Reduced folate carrier (RFC), a bidirectional anion exchanger, mediates folate delivery to a variety of cells. We selected three known RFC-1 polymorphisms (-43C>T, 80A>G, 696T>C) and investigated their relationship to cerebral infarction in the Korean population. We used the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to analyze associations between the three RFC-1 polymorphisms, disease status, and folate and homocysteine levels in 584 ischemic stroke patients, 353 SBI patients, and 505 control subjects. The frequencies of the RFC-1 -43TT, 80GG, and 696CC genotypes differed significantly between the stroke and control groups. The RFC-1 80A>G substitution was also associated with small artery occlusion and SBI. In a gene-environment analysis, the RFC-1 -43C>T, 80A>G, and 696T>C polymorphisms in the ischemic stroke group had combined effects with all environmental factors. In summary, we found that the RFC-1 -43C>T, 80A>G, and 696T>C polymorphisms may be risk factors for ischemic stroke.

  16. SPET brain imaging with 201 diethyldithiocarbamate in acute ischaemic stroke

    NARCIS (Netherlands)

    de Bruïne, J. F.; Limburg, M.; van Royen, E. A.; Hijdra, A.; Hill, T. C.; van der Schoot, J. B.

    1990-01-01

    Thirty-five patients with acute ischaemic stroke were studied within 24 h after hospital admission with thallium 201 diethyldithiocarbamate single photon emission tomography (201Tl-DDC SPET) and X-ray computed tomography (CT). 201Tl-DDC is a non-redistributing agent that allows postponed imaging

  17. Transcranial brain stimulation (TMS and tDCS for post-stroke aphasia rehabilitation: Controversies

    Directory of Open Access Journals (Sweden)

    Lucia Iracema Zanotto de Mendonça

    Full Text Available Transcranial brain stimulation (TS techniques have been investigated for use in the rehabilitation of post-stroke aphasia. According to previous reports, functional recovery by the left hemisphere improves recovery from aphasia, when compared with right hemisphere participation. TS has been applied to stimulate the activity of the left hemisphere or to inhibit homotopic areas in the right hemisphere. Various factors can interfere with the brain's response to TS, including the size and location of the lesion, the time elapsed since the causal event, and individual differences in the hemispheric language dominance pattern. The following questions are discussed in the present article: [a] Is inhibition of the right hemisphere truly beneficial?; [b] Is the transference of the language network to the left hemisphere truly desirable in all patients?; [c] Is the use of TS during the post-stroke subacute phase truly appropriate? Different patterns of neuroplasticity must occur in post-stroke aphasia.

  18. Brain-Machine Interface in chronic stroke rehabilitation: A controlled study

    NARCIS (Netherlands)

    Ramos-Murguialday, A.; Brötz, D.; Rea, M.; Laër, L.; Yilmaz, O.; Brasil, F.L.; Liberati, G.; Curado, M.R.; Garcia Cossio, E.; Vyziotis, A.; Cho, W.; Agostini, M.; Soares, E.; Soekadar, S.R.; Caria, A.; Cohen, L.G.; Birbaumer, N.

    2013-01-01

    Objective: Chronic stroke patients with severe hand weakness respond poorly to rehabilitation efforts. Here, we evaluated efficacy of daily brain-machine interface (BMI) training to increase the hypothesized beneficial effects of physiotherapy alone in patients with severe paresis in a double-blind

  19. Mapping causal functional contributions derived from the clinical assessment of brain damage after stroke.

    Science.gov (United States)

    Zavaglia, Melissa; Forkert, Nils D; Cheng, Bastian; Gerloff, Christian; Thomalla, Götz; Hilgetag, Claus C

    2015-01-01

    Lesion analysis reveals causal contributions of brain regions to mental functions, aiding the understanding of normal brain function as well as rehabilitation of brain-damaged patients. We applied a novel lesion inference technique based on game theory, Multi-perturbation Shapley value Analysis (MSA), to a large clinical lesion dataset. We used MSA to analyze the lesion patterns of 148 acute stroke patients together with their neurological deficits, as assessed by the National Institutes of Health Stroke Scale (NIHSS). The results revealed regional functional contributions to essential behavioral and cognitive functions as reflected in the NIHSS, particularly by subcortical structures. There were also side specific differences of functional contributions between the right and left hemispheric brain regions which may reflect the dominance of the left hemispheric syndrome aphasia in the NIHSS. Comparison of MSA to established lesion inference methods demonstrated the feasibility of the approach for analyzing clinical data and indicated its capability for objectively inferring functional contributions from multiple injured, potentially interacting sites, at the cost of having to predict the outcome of unknown lesion configurations. The analysis of regional functional contributions to neurological symptoms measured by the NIHSS contributes to the interpretation of this widely used standardized stroke scale in clinical practice as well as clinical trials and provides a first approximation of a 'map of stroke'.

  20. Plasticity in the Developing Brain: Intellectual, Language and Academic Functions in Children with Ischaemic Perinatal Stroke

    Science.gov (United States)

    Ballantyne, Angela O.; Spilkin, Amy M.; Hesselink, John; Trauner, Doris A.

    2008-01-01

    The developing brain has the capacity for a great deal of plasticity. A number of investigators have demonstrated that intellectual and language skills may be in the normal range in children following unilateral perinatal stroke. Questions have been raised, however, about whether these skills can be maintained at the same level as the brain…

  1. Clinical course of brain stroke in the persons exposed to ionizing radiation under the production conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bouchmanov, A. [State Research Center of Russia, Moscow (Russian Federation). Inst. of Biophysics

    2000-05-01

    The purpose was to study the risk factors and clinical course of brain strokes in professionally exposed workers being employed in plutonium production in comparison with a control group. The method and materials of study -clinical supervision and clinical database creation on 162 cases of brain stroke (128 males and 34 females) developed among professionally exposed workers. Age of patient varied from 21 to 68 years (in average -51.6 y.). The control group consisted of patients with the same diagnosis, worked on the same enterprise, but non-exposed to radiation. Data on the totally accumulated dose of external gamma radiation were received on the base of the individual dosimeters (from 0.1 cSv to 52 cSv, in average about 13 cSv); the plutonium-239 body content was estimated accordingly to the level of urine radionuclide excretion (from 0.4 kBq to 1.6 kBq, in average about 0.33 kBq). Muscle's hypertinsion and pathological great-toe reflexes in paretic legs and hands, hemianopsia, impressive and ataxic aphasia prevailed in the patients with ischemic brain strokes in system of internal carotid artery, exposed to radiation. The changes of muscle's tension, ataxia and nystagmus were marked more often in the professionals with ischemic brain strokes in system of vertebrobasilar artery. The illness proceeded more easy and with smaller frequency of frustration of consciousness and algesthesia, irrespective of a type ischemic brain strokes in the people exposed to ionizing radiation, than in patients of non-irradiated group. It was found that the arterial hypertension appeared to be the main risk factor for the brain stroke in both groups of patients (in 81.48% and 91.15% of cases). There was no marked differences in significance of risk factors and in main clinical parameters of various types of ischemic brain strokes among the patients professionally exposed to radiation in comparison with a control group. (author)

  2. The issues in the study of brain plasticity after stroke

    International Nuclear Information System (INIS)

    Zuo Chuantao

    2004-01-01

    Nowadays, the study on the plasticity of the brain is one of the hotspots in nerve scientific research. PET and fMRI provided powerful weapon to study brain plasticity, but some metholody can conflict the brain function study. The review elucide the the metholody questions from the choice of pantiets and control, defining motor recovery, the choice of motor task, the effect of brian morphological, interpreting changes in activation and analysis methods of PET images. (authors)

  3. The impact of large structural brain changes in chronic stroke patients on the electric field caused by transcranial brain stimulation

    DEFF Research Database (Denmark)

    Minjoli, Sena; Saturnino, Guilherme B.; Blicher, Jakob Udby

    2017-01-01

    . Realistic head models containing large cortical and subcortical stroke lesions in the right parietal cortex were created using MR images of two patients. For TMS, the electric field of a double coil was simulated using the finite-element method. Systematic variations of the coil position relative...... to the lesion were tested. For TDCS, the finite-element method was used to simulate a standard approach with two electrode pads, and the position of one electrode was systematically varied. For both TMS and TDCS, the lesion caused electric field " hot spots" in the cortex. However, these maxima were......Transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (TDCS) are two types of non-invasive transcranial brain stimulation (TBS). They are useful tools for stroke research and may be potential adjunct therapies for functional recovery. However, stroke often causes large...

  4. Formation and function of acute stroke-ready hospitals within a stroke system of care recommendations from the brain attack coalition.

    Science.gov (United States)

    Alberts, Mark J; Wechsler, Lawrence R; Jensen, Mary E Lee; Latchaw, Richard E; Crocco, Todd J; George, Mary G; Baranski, James; Bass, Robert R; Ruff, Robert L; Huang, Judy; Mancini, Barbara; Gregory, Tammy; Gress, Daryl; Emr, Marian; Warren, Margo; Walker, Michael D

    2013-12-01

    Many patients with an acute stroke live in areas without ready access to a Primary or Comprehensive Stroke Center. The formation of care facilities that meet the needs of these patients might improve their care and outcomes and guide them and emergency responders to such centers within a stroke system of care. The Brain Attack Coalition conducted an electronic search of the English medical literature from January 2000 to December 2012 to identify care elements and processes shown to be beneficial for acute stroke care. We used evidence grading and consensus paradigms to synthesize recommendations for Acute Stroke-Ready Hospitals (ASRHs). Several key elements for an ASRH were identified, including acute stroke teams, written care protocols, involvement of emergency medical services and emergency department, and rapid laboratory and neuroimaging testing. Unique aspects include the use of telemedicine, hospital transfer protocols, and drip and ship therapies. Emergent therapies include the use of intravenous tissue-type plasminogen activator and the reversal of coagulopathies. Although many of the care elements are similar to those of a Primary Stroke Center, compliance rates of ≥67% are suggested in recognition of the staffing, logistical, and financial challenges faced by rural facilities. ASRHs will form the foundation for acute stroke care in many settings. Recommended elements of an ASRH build on those proven to improve care and outcomes at Primary Stroke Centers. The ASRH will be a key component for patient care within an evolving stroke system of care.

  5. Results of brain perfusion Temp in acute ischaemic stroke

    International Nuclear Information System (INIS)

    Darcourt, J.; Migneco, O.; Mahagne, M.H.

    1999-01-01

    Perfusion SPECT allows immediate evaluation of cerebral ischaemia during the acute phase of stroke. Its prognostic value has been demonstrated by several studies. This prognostic value increases in comparison to clinical evaluation alone when injection is performed early after the first neurological signs. The classical three patterns fist described on PET studies by Marchal and Baron are also seen using SPECT: (pattern I) severe irreversible ischaemia with poor prognosis, (pattern III) normal study due to spontaneous reperfusion with complete clinical recovery and (pattern II) ischaemic penumbra with unpredictable prognosis. Two recent studies prove that SPECT can identify with high accuracy the extreme hemodynamic situations which are on one hand spontaneous re-perfusions (100 % sensitivity and specificity) and on the other hand the 'malignant middle cerebral artery infarctions' (82 % sensitivity and 98 % specificity). Therefore early SPECT is a valid tool to select stroke patients for thrombolytic therapy. (author)

  6. Computed tomography and brain scintigraphy in ischemic stroke

    International Nuclear Information System (INIS)

    Chiu, L.C.; Fodor, L.B.; Cornell, S.H.; Christie, J.H.

    1976-01-01

    Radionuclide and computed tomographic (CT) scans were reviewed in 215 patients with ischemic stroke. The findings vary depending on the site of vascular occlusion. In middle cerebral artery occlusion, four distinct patterns may be seen on the scintigrams. The CT scans show little variation in appearance. The tentorial confluence sign is an important finding on scintigrams of patients with occipital infarction; the absence of this sign should suggest another diagnosis. During the first week and after the fourth week following an ischemic stroke, the scintigram is usually negative, whereas the lesion is visible by CT. However, there are a significant number of false negative CT scans; therefore, both examinations are advocated in difficult cases

  7. Neurosurgical management of L-asparaginase induced haemorrhagic stroke.

    LENUS (Irish Health Repository)

    Ogbodo, Elisha

    2012-01-01

    The authors describe a case of L-asparaginase induced intracranial thrombosis and subsequent haemorrhage in a newly diagnosed 30-year-old man with acute lymphoblastic leukaemia who was successfully managed by surgical intervention. At presentation, he had a Glasgow Coma Score of 7\\/15, was aphasic and had dense right hemiplegia. Neuroimaging revealed an acute anterior left middle cerebral artery infarct with parenchymal haemorrhagic conversion, mass effect and subfalcine herniation. He subsequently underwent left frontal craniotomy and evacuation of large frontal haematoma and decompressive craniectomy for cerebral oedema. Six months postoperatively he underwent titanium cranioplasty. He had made good clinical recovery and is currently mobilising independently with mild occasional episodes of expressive dysphasia, difficulty with fine motor movement on the right side, and has remained seizure free. This is the first documented case of L-asparaginase induced haemorrhagic stroke managed by neurosurgical intervention. The authors emphasise the possible role of surgery in managing chemotherapy induced intracranial complications.

  8. MR-visible brain water content in human acute stroke

    DEFF Research Database (Denmark)

    Gideon, P; Rosenbaum, S; Sperling, B

    1999-01-01

    Quantification of metabolite concentrations by proton magnetic resonance spectroscopy (1H-MRS) in the human brain using water as an internal standard is based on the assumption that water content does not change significantly in pathologic brain tissue. To test this, we used 1H-MRS to estimate...

  9. Endogenous CNTF mediates stroke-induced adult CNS neurogenesis in mice

    Science.gov (United States)

    Kang, Seong Su; Keasey, Matthew P.; Arnold, Sheila A.; Reid, Rollie; Geralds, Justin; Hagg, Theo

    2013-01-01

    Focal brain ischemia in adult rats rapidly and robustly induces neurogenesis in the subventricular zone (SVZ) but there are few and inconsistent reports in mice, presenting a hurdle to genetically investigate the endogenous neurogenic regulators such as ciliary neurotrophic factor (CNTF). Here, we first provide a platform for further studies by showing that middle cerebral artery occlusion in adult male C57BL/6 mice robustly enhances neurogenesis in the SVZ only under very specific conditions, i.e., 14 days after a 30 min occlusion. CNTF expression paralleled changes in the number of proliferated, BrdU-positive, SVZ cells. Stroke-induced proliferation was absent in CNTF−/− mice, suggesting that it is mediated by CNTF. MCAO-increased CNTF appears to act on C cell proliferation and by inducing FGF2 expression but not via EGF expression or Notch1 signaling of neural stem cells in the SVZ. CNTF is unique, as expression of other gp130 ligands, IL-6 and LIF, did not predict SVZ proliferation or showed no or only small compensatory increases in CNTF−/− mice. Expression of tumor necrosis factor-α, which can inhibit neurogenesis, and the presence of leukocytes in the SVZ were inversely correlated with neurogenesis, but pro-inflammatory cytokines did not affect CNTF expression in cultured astrocytes. These results suggest that slowly up-regulated CNTF in the SVZ mediates stroke-induced neurogenesis and is counteracted by inflammation. Further pharmacological stimulation of endogenous CNTF might be a good therapeutic strategy for cell replacement after stroke as CNTF regulates normal patterns of neurogenesis and is expressed almost exclusively in the nervous system. PMID:22960105

  10. Current trends in stroke rehabilitation. A review with focus on brain plasticity.

    Science.gov (United States)

    Johansson, B B

    2011-03-01

    Current understanding of brain plasticity has lead to new approaches in ischemic stroke rehabilitation. Stroke units that combine good medical and nursing care with task-oriented intense training in an environment that provides confidence, stimulation and motivation significantly improve outcome. Repetitive trans-cranial magnetic stimulation (rTMS), and trans-cranial direct current stimulation (tDCS) are applied in rehabilitation of motor function. The long-term effect, optimal way of stimulation and possibly efficacy in cognitive rehabilitation need evaluation. Methods based on multisensory integration of motor, cognitive, and perceptual processes including action observation, mental training, and virtual reality are being tested. Different approaches of intensive aphasia training are described. Recent data on intensive melodic intonation therapy indicate that even patients with very severe non-fluent aphasia can regain speech through homotopic white matter tract plasticity. Music therapy is applied in motor and cognitive rehabilitation. To avoid the confounding effect of spontaneous improvement, most trials are preformed ≥3 months post stroke. Randomized controlled trials starting earlier after strokes are needed. More attention should be given to stroke heterogeneity, cognitive rehabilitation, and social adjustment and to genetic differences, including the role of BDNF polymorphism in brain plasticity. © 2010 John Wiley & Sons A/S.

  11. Diagnosis of small posterior fossa stroke on brain CT: effect of iterative reconstruction designed for brain CT on detection performance

    International Nuclear Information System (INIS)

    Inoue, Taihei; Yoshida, Morikatsu; Yokoyama, Koichi; Nakaura, Takeshi; Hirata, Kenichiro; Kidoh, Masafumi; Oda, Seitaro; Utsunomiya, Daisuke; Yamashita, Yasuyuki; Harada, Kazunori

    2017-01-01

    In this study, we aimed to determine whether iterative model reconstruction designed for brain CT (IMR-neuro) would improve the accuracy of posterior fossa stroke diagnosis on brain CT. We enrolled 37 patients with ischaemic stroke in the posterior fossa and 37 patients without stroke (controls). Using axial images reconstructed using filtered back-projection (FBP) and IMR-neuro, we compared the CT numbers in infarcted areas, image noise in the pons, and contrast-to-noise ratios (CNRs) of infarcted and non-infarcted areas on scans subjected to IMR-neuro and FBP. To analyse the performance of hypo-attenuation detection, we used receiver-operating characteristic (ROC) curve techniques. The image noise was significantly lower (2.2 ± 0.5 vs. 5.1 ± 0.9 Hounsfield units, p < 0.01) and the difference in CNR between the infarcted and non-infarcted areas was significantly higher with IMR-neuro than with FBP (2.2 ± 1.7 vs. 4.0 ± 3.6, p < 0.01). Furthermore, the average area under the ROC curve was significantly higher with IMR-neuro (0.90 vs. 0.86 for FBP, p = 0.04). IMR-neuro yielded better image quality and improved hypo-attenuation detection in patients with ischaemic stroke. (orig.)

  12. Diagnosis of small posterior fossa stroke on brain CT: effect of iterative reconstruction designed for brain CT on detection performance

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Taihei; Yoshida, Morikatsu; Yokoyama, Koichi [Amakusa Medical Center, Department of Radiology, Amakusa, Kumamoto (Japan); Nakaura, Takeshi; Hirata, Kenichiro; Kidoh, Masafumi; Oda, Seitaro; Utsunomiya, Daisuke; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Graduate School of Life Sciences, Kumamoto (Japan); Harada, Kazunori [Amakusa Medical Center, Department of Surgery, Kumamoto (Japan)

    2017-09-15

    In this study, we aimed to determine whether iterative model reconstruction designed for brain CT (IMR-neuro) would improve the accuracy of posterior fossa stroke diagnosis on brain CT. We enrolled 37 patients with ischaemic stroke in the posterior fossa and 37 patients without stroke (controls). Using axial images reconstructed using filtered back-projection (FBP) and IMR-neuro, we compared the CT numbers in infarcted areas, image noise in the pons, and contrast-to-noise ratios (CNRs) of infarcted and non-infarcted areas on scans subjected to IMR-neuro and FBP. To analyse the performance of hypo-attenuation detection, we used receiver-operating characteristic (ROC) curve techniques. The image noise was significantly lower (2.2 ± 0.5 vs. 5.1 ± 0.9 Hounsfield units, p < 0.01) and the difference in CNR between the infarcted and non-infarcted areas was significantly higher with IMR-neuro than with FBP (2.2 ± 1.7 vs. 4.0 ± 3.6, p < 0.01). Furthermore, the average area under the ROC curve was significantly higher with IMR-neuro (0.90 vs. 0.86 for FBP, p = 0.04). IMR-neuro yielded better image quality and improved hypo-attenuation detection in patients with ischaemic stroke. (orig.)

  13. MECHANISMS OF SECONDARY BRAIN DAMAGE IN COMA DEVELOPED IN ACUTE PERIOD OF ISCHEMIC STROKE

    Directory of Open Access Journals (Sweden)

    Константин Владимирович Лукашев

    2017-06-01

    Conclusions. One of the mechanisms of secondary brain damage in patients in coma in acute period of ischemic stroke is a worsening dysfunction of the brain stem followed bythe cerebral autoregulationdisturbance in the absence of a significant increase of intracranial pressure.This causes disturbances of the central hemodynamics, the mechanical and gas exchange properties,the accumulation of extravascular lung water.These processesresult in acute lung injury, itbeing a critical element in the development and progression of systemic hypoxia as a key mechanism of secondary brain damage.

  14. Correlation between Nerve Growth Factor (NGF with Brain Derived Neurotropic Factor (BDNF in Ischemic Stroke Patient

    Directory of Open Access Journals (Sweden)

    Joko Widodo

    2016-05-01

    Full Text Available Background: The neurotrophins nerve growth factor (NGF and brain-derived neurotrophic factor (BDNF is a family of polypeptides that play critical role during neuronal development, appear to mediate protective role on neurorepair in ischemic stroke. Naturally in adult brain neurorepair process consist of: angiogenesis, neurogenesis, and neuronal plasticity, it can also be stimulated by endogenous neurorepair. In this study we observed correlation between NGF and BDNF ischemic stroke patient’s onset: 7-30 and over 30 days. Methods: This is cross sectional study on 46 subjects aged 38 – 74 years old with ischemic stroke from The Indonesian Central Hospital of Army Gatot Subroto Jakarta. Diagnosis of ischemic stroke was made using clinical examination and magnetic resonance imaging (MRI by neurologist. Subjects were divided into 2 groups based on stroke onset: 7 – 30 days (Group A: 19 subjects and > 30 days (Group B: 27 Subjects. Serum NGF levels were measured with ELISA method and BDNF levels were measured using multiplex method with Luminex Magpix. Results: Levels of NGF and BDNF were significantly different between onset group A and B (NGF p= 0.022, and BDNF p=0.008, with mean levels NGF in group A higher than group B, indicating that BDNF levels is lower in group A than group B. There was no significant correlation between NGF and BDNF levels in all groups. Conclusion: The variations in neurotrophic factor levels reflect an endogenous attempt at neuroprotection against biochemical and molecular changes after ischemic stroke. NGF represents an early marker of brain injury while BDNF recovery is most prominent during the first 14 days after onsite but continuous for more than 30 days. There is no significant correlation between NGF and BDNF in each group.  

  15. Lycium barbarum Extracts Protect the Brain from Blood-Brain Barrier Disruption and Cerebral Edema in Experimental Stroke

    Science.gov (United States)

    Yang, Di; Li, Suk-Yee; Yeung, Chung-Man; Chang, Raymond Chuen-Chung; So, Kwok-Fai; Wong, David; Lo, Amy C. Y.

    2012-01-01

    Background and Purpose Ischemic stroke is a destructive cerebrovascular disease and a leading cause of death. Yet, no ideal neuroprotective agents are available, leaving prevention an attractive alternative. The extracts from the fruits of Lycium barbarum (LBP), a Chinese anti-aging medicine and food supplement, showed neuroprotective function in the retina when given prophylactically. We aim to evaluate the protective effects of LBP pre-treatment in an experimental stroke model. Methods C57BL/6N male mice were first fed with either vehicle (PBS) or LBP (1 or 10 mg/kg) daily for 7 days. Mice were then subjected to 2-hour transient middle cerebral artery occlusion (MCAO) by the intraluminal method followed by 22-hour reperfusion upon filament removal. Mice were evaluated for neurological deficits just before sacrifice. Brains were harvested for infarct size estimation, water content measurement, immunohistochemical analysis, and Western blot experiments. Evans blue (EB) extravasation was determined to assess blood-brain barrier (BBB) disruption after MCAO. Results LBP pre-treatment significantly improved neurological deficits as well as decreased infarct size, hemispheric swelling, and water content. Fewer apoptotic cells were identified in LBP-treated brains by TUNEL assay. Reduced EB extravasation, fewer IgG-leaky vessels, and up-regulation of occludin expression were also observed in LBP-treated brains. Moreover, immunoreactivity for aquaporin-4 and glial fibrillary acidic protein were significantly decreased in LBP-treated brains. Conclusions Seven-day oral LBP pre-treatment effectively improved neurological deficits, decreased infarct size and cerebral edema as well as protected the brain from BBB disruption, aquaporin-4 up-regulation, and glial activation. The present study suggests that LBP may be used as a prophylactic neuroprotectant in patients at high risk for ischemic stroke. PMID:22438957

  16. Robotic devices and brain-machine interfaces for hand rehabilitation post-stroke.

    Science.gov (United States)

    McConnell, Alistair C; Moioli, Renan C; Brasil, Fabricio L; Vallejo, Marta; Corne, David W; Vargas, Patricia A; Stokes, Adam A

    2017-06-28

    To review the state of the art of robotic-aided hand physiotherapy for post-stroke rehabilitation, including the use of brain-machine interfaces. Each patient has a unique clinical history and, in response to personalized treatment needs, research into individualized and at-home treatment options has expanded rapidly in recent years. This has resulted in the development of many devices and design strategies for use in stroke rehabilitation. The development progression of robotic-aided hand physiotherapy devices and brain-machine interface systems is outlined, focussing on those with mechanisms and control strategies designed to improve recovery outcomes of the hand post-stroke. A total of 110 commercial and non-commercial hand and wrist devices, spanning the 2 major core designs: end-effector and exoskeleton are reviewed. The growing body of evidence on the efficacy and relevance of incorporating brain-machine interfaces in stroke rehabilitation is summarized. The challenges involved in integrating robotic rehabilitation into the healthcare system are discussed. This review provides novel insights into the use of robotics in physiotherapy practice, and may help system designers to develop new devices.

  17. Regional brain structural abnormality in ischemic stroke patients: a voxel-based morphometry study

    Directory of Open Access Journals (Sweden)

    Ping Wu

    2016-01-01

    Full Text Available Our previous study used regional homogeneity analysis and found that activity in some brain areas of patients with ischemic stroke changed significantly. In the current study, we examined structural changes in these brain regions by taking structural magnetic resonance imaging scans of 11 ischemic stroke patients and 15 healthy participants, and analyzing the data using voxel-based morphometry. Compared with healthy participants, patients exhibited higher gray matter density in the left inferior occipital gyrus and right anterior white matter tract. In contrast, gray matter density in the right cerebellum, left precentral gyrus, right middle frontal gyrus, and left middle temporal gyrus was less in ischemic stroke patients. The changes of gray matter density in the middle frontal gyrus were negatively associated with the clinical rating scales of the Fugl-Meyer Motor Assessment (r = -0.609, P = 0.047 and the left middle temporal gyrus was negatively correlated with the clinical rating scales of the nervous functional deficiency scale (r = -0.737, P = 0.010. Our findings can objectively identify the functional abnormality in some brain regions of ischemic stroke patients.

  18. Regional brain structural abnormality in ischemic stroke patients: a voxel-based morphometry study.

    Science.gov (United States)

    Wu, Ping; Zhou, Yu-Mei; Zeng, Fang; Li, Zheng-Jie; Luo, Lu; Li, Yong-Xin; Fan, Wei; Qiu, Li-Hua; Qin, Wei; Chen, Lin; Bai, Lin; Nie, Juan; Zhang, San; Xiong, Yan; Bai, Yu; Yin, Can-Xin; Liang, Fan-Rong

    2016-09-01

    Our previous study used regional homogeneity analysis and found that activity in some brain areas of patients with ischemic stroke changed significantly. In the current study, we examined structural changes in these brain regions by taking structural magnetic resonance imaging scans of 11 ischemic stroke patients and 15 healthy participants, and analyzing the data using voxel-based morphometry. Compared with healthy participants, patients exhibited higher gray matter density in the left inferior occipital gyrus and right anterior white matter tract. In contrast, gray matter density in the right cerebellum, left precentral gyrus, right middle frontal gyrus, and left middle temporal gyrus was less in ischemic stroke patients. The changes of gray matter density in the middle frontal gyrus were negatively associated with the clinical rating scales of the Fugl-Meyer Motor Assessment ( r = -0.609, P = 0.047) and the left middle temporal gyrus was negatively correlated with the clinical rating scales of the nervous functional deficiency scale ( r = -0.737, P = 0.010). Our findings can objectively identify the functional abnormality in some brain regions of ischemic stroke patients.

  19. Brain strokes related to aortic aneurysma – the analysis of three cases

    Directory of Open Access Journals (Sweden)

    Pastuszak Żanna

    2017-04-01

    Full Text Available Brain stroke connected with aortic blood flow disturbances is a rare disease and its incidence is difficult to assume. Nevertheless, 10-50% of patients with aortic dissection may not experience any pain. In case of 18-30% patients with aortic dissection neurological signs are first disease presentation and among them ischemic stroke is the most common. The most popular aortic dissection classification is with use of Stanford system. Type A involves the ascending aorta and type B is occurring distal to the subclavian artery. Aortic dissection risk factors include hypertension, cystic medionecrosis, bicuspid aortic valve and Marfan’s or Ehlers-Danlos syndrome.

  20. Optical scatter imaging of cellular and mitochondrial swelling in brain tissue models of stroke

    Science.gov (United States)

    Johnson, Lee James

    2001-08-01

    The severity of brain edema resulting from a stroke can determine a patient's survival and the extent of their recovery. Cellular swelling is the microscopic source of a significant part of brain edema. Mitochondrial swelling also appears to be a determining event in the death or survival of the cells that are injured during a stroke. Therapies for reducing brain edema are not effective in many cases and current treatments of stroke do not address mitochondrial swelling at all. This dissertation is motivated by the lack of a complete understanding of cellular swelling resulting from stroke and the lack of a good method to begin to study mitochondrial swelling resulting from stroke in living brain tissue. In this dissertation, a novel method of detecting mitochondrial and cellular swelling in living hippocampal slices is developed and validated. The system is used to obtain spatial and temporal information about cellular and mitochondrial swelling resulting from various models of stroke. The effect of changes in water content on light scatter and absorption are examined in two models of brain edema. The results of this study demonstrate that optical techniques can be used to detect changes in water content. Mie scatter theory, the theoretical basis of the dual- angle scatter ratio imaging system, is presented. Computer simulations based on Mie scatter theory are used to determine the optimal angles for imaging. A detailed account of the early systems is presented to explain the motivations for the system design, especially polarization, wavelength and light path. Mitochondrial sized latex particles are used to determine the system response to changes in scattering particle size and concentration. The dual-angle scatter ratio imaging system is used to distinguish between osmotic and excitotoxic models of stroke injury. Such distinction cannot be achieved using the current techniques to study cellular swelling in hippocampal slices. The change in the scatter ratio is

  1. Blast-induced Mild Traumatic Brain Injury

    Science.gov (United States)

    2010-01-01

    directly to the brain after craniotomy 154 or 240 kPa Unknown 2.8 or 20 kPa 40 kPa 1 or 10 MPa Redistribution of phosphorylated neurofilament H...m a: 1𔃻) .... !l ~ Blast-induced Mild Traumatic Brain Injury 767 colleagues55 compared neuropsychological test results in a group of primarily...patterns between blast and non-blast-injured subjects, thus providing no support at the neuropsychological level that blast is different. However

  2. Decreased integration and information capacity in stroke measured by whole brain models of resting state activity.

    Science.gov (United States)

    Adhikari, Mohit H; Hacker, Carl D; Siegel, Josh S; Griffa, Alessandra; Hagmann, Patric; Deco, Gustavo; Corbetta, Maurizio

    2017-04-01

    While several studies have shown that focal lesions affect the communication between structurally normal regions of the brain, and that these changes may correlate with behavioural deficits, their impact on brain's information processing capacity is currently unknown. Here we test the hypothesis that focal lesions decrease the brain's information processing capacity, of which changes in functional connectivity may be a measurable correlate. To measure processing capacity, we turned to whole brain computational modelling to estimate the integration and segregation of information in brain networks. First, we measured functional connectivity between different brain areas with resting state functional magnetic resonance imaging in healthy subjects (n = 26), and subjects who had suffered a cortical stroke (n = 36). We then used a whole-brain network model that coupled average excitatory activities of local regions via anatomical connectivity. Model parameters were optimized in each healthy or stroke participant to maximize correlation between model and empirical functional connectivity, so that the model's effective connectivity was a veridical representation of healthy or lesioned brain networks. Subsequently, we calculated two model-based measures: 'integration', a graph theoretical measure obtained from functional connectivity, which measures the connectedness of brain networks, and 'information capacity', an information theoretical measure that cannot be obtained empirically, representative of the segregative ability of brain networks to encode distinct stimuli. We found that both measures were decreased in stroke patients, as compared to healthy controls, particularly at the level of resting-state networks. Furthermore, we found that these measures, especially information capacity, correlate with measures of behavioural impairment and the segregation of resting-state networks empirically measured. This study shows that focal lesions affect the brain's ability to

  3. Dose-response relationships using brain-computer interface technology impact stroke rehabilitation.

    Science.gov (United States)

    Young, Brittany M; Nigogosyan, Zack; Walton, Léo M; Remsik, Alexander; Song, Jie; Nair, Veena A; Tyler, Mitchell E; Edwards, Dorothy F; Caldera, Kristin; Sattin, Justin A; Williams, Justin C; Prabhakaran, Vivek

    2015-01-01

    Brain-computer interfaces (BCIs) are an emerging novel technology for stroke rehabilitation. Little is known about how dose-response relationships for BCI therapies affect brain and behavior changes. We report preliminary results on stroke patients (n = 16, 11 M) with persistent upper extremity motor impairment who received therapy using a BCI system with functional electrical stimulation of the hand and tongue stimulation. We collected MRI scans and behavioral data using the Action Research Arm Test (ARAT), 9-Hole Peg Test (9-HPT), and Stroke Impact Scale (SIS) before, during, and after the therapy period. Using anatomical and functional MRI, we computed Laterality Index (LI) for brain activity in the motor network during impaired hand finger tapping. Changes from baseline LI and behavioral scores were assessed for relationships with dose, intensity, and frequency of BCI therapy. We found that gains in SIS Strength were directly responsive to BCI therapy: therapy dose and intensity correlated positively with increased SIS Strength (p ≤ 0.05), although no direct relationships were identified with ARAT or 9-HPT scores. We found behavioral measures that were not directly sensitive to differences in BCI therapy administration but were associated with concurrent brain changes correlated with BCI therapy administration parameters: therapy dose and intensity showed significant (p ≤ 0.05) or trending (0.05 < p < 0.1) negative correlations with LI changes, while therapy frequency did not affect LI. Reductions in LI were then correlated (p ≤ 0.05) with increased SIS Activities of Daily Living scores and improved 9-HPT performance. Therefore, some behavioral changes may be reflected by brain changes sensitive to differences in BCI therapy administration, while others such as SIS Strength may be directly responsive to BCI therapy administration. Data preliminarily suggest that when using BCI in stroke rehabilitation, therapy frequency may be less important than dose and

  4. Stroke

    Science.gov (United States)

    ... adjust your treatment as needed. Rehabilitation After a stroke, you may need rehabilitation (rehab) to help you recover. Rehab may include working with speech, physical, and occupational therapists. Language, ... may have trouble communicating after a stroke. You may not be able to find the ...

  5. Using Brain Oscillations and Corticospinal Excitability to Understand and Predict Post-Stroke Motor Function

    Directory of Open Access Journals (Sweden)

    Aurore Thibaut

    2017-05-01

    Full Text Available What determines motor recovery in stroke is still unknown and finding markers that could predict and improve stroke recovery is a challenge. In this study, we aimed at understanding the neural mechanisms of motor function recovery after stroke using neurophysiological markers by means of cortical excitability (transcranial magnetic stimulation—TMS and brain oscillations (electroencephalography—EEG. In this cross-sectional study, 55 subjects with chronic stroke (62 ± 14 yo, 17 women, 32 ± 42 months post-stroke were recruited in two sites. We analyzed TMS measures (i.e., motor threshold—MT—of the affected and unaffected sides and EEG variables (i.e., power spectrum in different frequency bands and different brain regions of the affected and unaffected hemispheres and their correlation with motor impairment as measured by Fugl-Meyer. Multiple univariate and multivariate linear regression analyses were performed to identify the predictors of good motor function. A significant interaction effect of MT in the affected hemisphere and power in beta bandwidth over the central region for both affected and unaffected hemispheres was found. We identified that motor function positively correlates with beta rhythm over the central region of the unaffected hemisphere, while it negatively correlates with beta rhythm in the affected hemisphere. Our results suggest that cortical activity in the affected and unaffected hemisphere measured by EEG provides new insights on the association between high-frequency rhythms and motor impairment, highlighting the role of an excess of beta in the affected central cortical region in poor motor function in stroke recovery.

  6. Induction of neuroplasticity and recovery in post-stroke aphasia by non-invasive brain stimulation.

    Science.gov (United States)

    Shah, Priyanka P; Szaflarski, Jerzy P; Allendorfer, Jane; Hamilton, Roy H

    2013-12-24

    Stroke victims tend to prioritize speaking, writing, and walking as the three most important rehabilitation goals. Of note is that two of these goals involve communication. This underscores the significance of developing successful approaches to aphasia treatment for the several hundred thousand new aphasia patients each year and over 1 million stroke survivors with chronic aphasia in the U.S. alone. After several years of growth as a research tool, non-invasive brain stimulation (NBS) is gradually entering the arena of clinical aphasiology. In this review, we first examine the current state of knowledge of post-stroke language recovery including the contributions from the dominant and non-dominant hemispheres. Next, we briefly discuss the methods and the physiologic basis of the use of inhibitory and excitatory repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) as research tools in patients who experience post-stroke aphasia. Finally, we provide a critical review of the most influential evidence behind the potential use of these two brain stimulation methods as clinical rehabilitative tools.

  7. Induction of neuroplasticity and recovery in post-stroke aphasia by non-invasive brain stimulation

    Directory of Open Access Journals (Sweden)

    Priyanka eShah

    2013-12-01

    Full Text Available Stroke victims tend to prioritize speaking, writing and walking as the three most important rehabilitation goals. Of note is that two of these goals involve communication. This underscores the significance of developing successful approaches to aphasia treatment for the several hundred thousand new aphasia patients each year and over 1 million stroke survivors with chronic aphasia in the U.S. alone. After several years of growth as a research tool, noninvasive brain stimulation (NBS is gradually entering the arena of clinical aphasiology. In this review, we first examine the current state of knowledge of post-stroke language recovery including the contributions from the dominant and non-dominant hemispheres. Next, we briefly discuss the methods and the physiologic basis of the use of inhibitory and excitatory repetitive transcranial magnetic stimulation (rTMS and transcranial direct current stimulation (tDCS as research tools in patients who experience post-stroke aphasia. Finally, we provide a critical review of the most influential evidence behind the potential use of these two brain stimulation methods as clinical rehabilitative tools.

  8. Brain-computer interfaces in the completely locked-in state and chronic stroke.

    Science.gov (United States)

    Chaudhary, U; Birbaumer, N; Ramos-Murguialday, A

    2016-01-01

    Brain-computer interfaces (BCIs) use brain activity to control external devices, facilitating paralyzed patients to interact with the environment. In this chapter, we discuss the historical perspective of development of BCIs and the current advances of noninvasive BCIs for communication in patients with amyotrophic lateral sclerosis and for restoration of motor impairment after severe stroke. Distinct techniques have been explored to control a BCI in patient population especially electroencephalography (EEG) and more recently near-infrared spectroscopy (NIRS) because of their noninvasive nature and low cost. Previous studies demonstrated successful communication of patients with locked-in state (LIS) using EEG- and invasive electrocorticography-BCI and intracortical recordings when patients still showed residual eye control, but not with patients with complete LIS (ie, complete paralysis). Recently, a NIRS-BCI and classical conditioning procedure was introduced, allowing communication in patients in the complete locked-in state (CLIS). In severe chronic stroke without residual hand function first results indicate a possible superior motor rehabilitation to available treatment using BCI training. Here we present an overview of the available studies and recent results, which open new doors for communication, in the completely paralyzed and rehabilitation in severely affected stroke patients. We also reflect on and describe possible neuronal and learning mechanisms responsible for BCI control and perspective for future BMI research for communication in CLIS and stroke motor recovery. © 2016 Elsevier B.V. All rights reserved.

  9. 99mTc-HMPAO perfusion indices and brain-mapping in stroke patients

    International Nuclear Information System (INIS)

    Minchev, D.; Klisarova, A.

    1997-01-01

    It is the purpose of the study to establish correlations between 99mTc-HMPAO (hexamethylpropylenaminoxym) perfusion indices and changes in brain-mapping among patients with acute stroke. Forty-six patients with definitely proved stroke syndrome are investigated in the first 72 hours and 15 days after the onset of cerebrovascular accident using clinical, neuro-physiological and 99mTc-HMPAO SPECT methods. Regional and hemispheric perfusion asymmetry correlate with the brain-mapping cerebral disturbance (p < 0.001). In patients presenting focal hypoperfusion there is a significant correlation between perfusion indices and local EEG disturbance (r = 0.87). The dynamic study demonstrates a significant correlation between perfusion indices and electrical cerebral disturbance in the first 72 hours after the onset of the cerebrovascular accident. Fifteen days later no such correlation is documented. The obtained results demonstrate the essential practical bearing of 99mTc-HMPAO SPECT indices on the objective assessment of perfusion hemispheric and regional asymmetry in stroke patients, and the possibility of being used for indirect estimation of the regional cerebral blood flow in acute stroke patients against the background of visual and quantitative EEG changes (author)

  10. Robotics, Stem Cells and Brain Computer Interfaces in Rehabilitation and Recovery from Stroke; Updates and Advances

    Science.gov (United States)

    Boninger, Michael L; Wechsler, Lawrence R.; Stein, Joel

    2014-01-01

    Objective To describe the current state and latest advances in robotics, stem cells, and brain computer interfaces in rehabilitation and recovery for stroke. Design The authors of this summary recently reviewed this work as part of a national presentation. The paper represents the information included in each area. Results Each area has seen great advances and challenges as products move to market and experiments are ongoing. Conclusion Robotics, stem cells, and brain computer interfaces all have tremendous potential to reduce disability and lead to better outcomes for patients with stroke. Continued research and investment will be needed as the field moves forward. With this investment, the potential for recovery of function is likely substantial PMID:25313662

  11. Prediction of prognosis of upper-extremity function following stroke-related paralysis using brain imaging.

    Science.gov (United States)

    Nakashima, Akira; Moriuchi, Takefumi; Mitsunaga, Wataru; Yonezawa, Takehito; Kataoka, Hideki; Nakashima, Ryusei; Koizumi, Tetsuji; Shimizu, Tadashi; Ryu, Nobutoshi; Higashi, Toshio

    2017-08-01

    [Purpose] Diffusion tensor imaging (DTI) has attracted attention as a method for determining prognosis following paralysis after stroke. However, DTI can assess the degree of damage to the corticospinal tract but cannot evaluate other brain regions. In this study, we examined in detail the prognosis of upper-limb function of the paralyzed side following stroke, using DTI and voxel-based morphometry (VBM). [Subjects and Methods] We studied 17 consecutive patients diagnosed with stroke, including hemorrhagic and ischemic types, who exhibited hemiparesis and were treated in our hospital. DTI and VBM were performed 14 days after admission. Outcome measurements that assessed upper limb function were Fugl-Meyer Assessment (FMA) and Motor Activity Log (MAL), which were applied after 3 months. [Results] The fractional anisotropy ratio of the bilateral cerebral peduncles (rFA) was significantly correlated with FMA, amount of use, and quality of movement 3 months after stroke. The precentral gyrus significantly degenerated as compared with the control group for a case with notable motor paralysis, for which rFA was high. [Conclusion] We suggest it may be possible to predict recovery of upper limb function following stroke by combining DTI and VBM visualization methods.

  12. Goreisan Prevents Brain Edema after Cerebral Ischemic Stroke by Inhibiting Aquaporin 4 Upregulation in Mice.

    Science.gov (United States)

    Nakano, Takafumi; Nishigami, Chisa; Irie, Keiichi; Shigemori, Yutaka; Sano, Kazunori; Yamashita, Yuta; Myose, Takayuki; Tominaga, Koji; Matsuo, Koichi; Nakamura, Yoshihiko; Ishikura, Hiroyasu; Kamimura, Hidetoshi; Egawa, Takashi; Mishima, Kenichi

    2018-03-01

    Aquaporin 4 (AQP4) is a water-selective transport protein expressed in astrocytes throughout the central nervous system. AQP4 level increases after cerebral ischemia and results in ischemic brain edema. Brain edema markedly influences mortality and motor function by elevating intracranial pressure that leads to secondary brain damage. Therefore, AQP4 is an important target to improve brain edema after cerebral ischemia. The Japanese herbal Kampo medicine, goreisan, is known to inhibit AQP4 activity. Here, we investigated whether goreisan prevents induction of brain edema by cerebral ischemia via AQP4 using 4-hour middle cerebral artery occlusion (4h MCAO) mice. Goreisan was orally administered at a dose of 500 mg/kg twice a day for 5 days before MCAO. AQP4 expression and motor coordination were measured by Western blotting and rotarod test, respectively. Brain water content of 4h MCAO mice was significantly increased at 24 hours after MCAO. Treatment with goreisan significantly decreased both brain water content and AQP4 expression in the ischemic brain at 24 hours after MCAO. In addition, treatment with goreisan alleviated motor coordination deficits at 24 hours after MCAO. The results of this study suggested that goreisan may be a useful new therapeutic option for ischemic brain edema. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  13. Brain metabolic pattern analysis using a magnetic resonance spectra classification software in experimental stroke.

    Science.gov (United States)

    Jiménez-Xarrié, Elena; Davila, Myriam; Candiota, Ana Paula; Delgado-Mederos, Raquel; Ortega-Martorell, Sandra; Julià-Sapé, Margarida; Arús, Carles; Martí-Fàbregas, Joan

    2017-01-13

    Magnetic resonance spectroscopy (MRS) provides non-invasive information about the metabolic pattern of the brain parenchyma in vivo. The SpectraClassifier software performs MRS pattern-recognition by determining the spectral features (metabolites) which can be used objectively to classify spectra. Our aim was to develop an Infarct Evolution Classifier and a Brain Regions Classifier in a rat model of focal ischemic stroke using SpectraClassifier. A total of 164 single-voxel proton spectra obtained with a 7 Tesla magnet at an echo time of 12 ms from non-infarcted parenchyma, subventricular zones and infarcted parenchyma were analyzed with SpectraClassifier ( http://gabrmn.uab.es/?q=sc ). The spectra corresponded to Sprague-Dawley rats (healthy rats, n = 7) and stroke rats at day 1 post-stroke (acute phase, n = 6 rats) and at days 7 ± 1 post-stroke (subacute phase, n = 14). In the Infarct Evolution Classifier, spectral features contributed by lactate + mobile lipids (1.33 ppm), total creatine (3.05 ppm) and mobile lipids (0.85 ppm) distinguished among non-infarcted parenchyma (100% sensitivity and 100% specificity), acute phase of infarct (100% sensitivity and 95% specificity) and subacute phase of infarct (78% sensitivity and 100% specificity). In the Brain Regions Classifier, spectral features contributed by myoinositol (3.62 ppm) and total creatine (3.04/3.05 ppm) distinguished among infarcted parenchyma (100% sensitivity and 98% specificity), non-infarcted parenchyma (84% sensitivity and 84% specificity) and subventricular zones (76% sensitivity and 93% specificity). SpectraClassifier identified candidate biomarkers for infarct evolution (mobile lipids accumulation) and different brain regions (myoinositol content).

  14. Moderately delayed post-insult treatment with normobaric hyperoxia reduces excitotoxin-induced neuronal degeneration but increases ischemia-induced brain damage

    Directory of Open Access Journals (Sweden)

    Haelewyn Benoit

    2011-04-01

    Full Text Available Abstract Background The use and benefits of normobaric oxygen (NBO in patients suffering acute ischemic stroke is still controversial. Results Here we show for the first time to the best of our knowledge that NBO reduces both NMDA-induced calcium influxes in vitro and NMDA-induced neuronal degeneration in vivo, but increases oxygen and glucose deprivation-induced cell injury in vitro and ischemia-induced brain damage produced by middle cerebral artery occlusion in vivo. Conclusions Taken together, these results indicate that NBO reduces excitotoxin-induced calcium influx and subsequent neuronal degeneration but favors ischemia-induced brain damage and neuronal death. These findings highlight the complexity of the mechanisms involved by the use of NBO in patients suffering acute ischemic stroke.

  15. Stroke And Substance Abuse

    Directory of Open Access Journals (Sweden)

    A Chitsaz

    2017-02-01

    Full Text Available Introduction: stroke in recreational substance users can be an indirect complication, like endocarditis and cardio embolism in parenteral drug users. With some drug like cocaine, stroke appear to be the result of a direct effect. In young subjects without other risk factors provide persuasive evidence for causality . OPIATES: Heroine is the most abused opiate drug, which is administered by injection, by snorting or by smoking. Stroke affects heroin users by diverse mechanisms,. Injectors are at risk of infections endocarditis, which carries risk for both ischemic and hemorrhagic stroke. Cerebral or subarachnoid hemorrhage usually occurs after rupture of a septic (mycotic aneurysm. Heroine users can are also at risk for hemorrhagic stroke secondary to liver failure with deranged clotting and to heroin nephropathy with uremia or malignant hypertension. In some heroin users the drug it self is directly causal due to vasculitis, hypersensitivity and immunologic changes. Embolization of foreign material to brain due to mixed of heroine with quinine can cause cerebral embolism. AMPHETAMINE AND other psychostimulants: In abuser of amphetamine hemorrhagic stroke can occur, oral, intravenous, nasal, and inhalational routes of administration have been reported. Most were chronic user, but in several patients, stroke followed a first exposure. Some of amphetamine induced intracranial hemorrhages are secondary to acute hypertension, some to cerebral vacuities, and some to a combination of two. Decongestants and diet pills: Phenylpropanolamine (PPA, an amphetamine – like drug, in decongestants and diet pills, induce acute hypertension, sever headache, psychiatric symptoms, seizures and hemorrhagic stroke. Ephedrine and pseudo ephedrine are present in decongestants and bronchodilators and induce headache, tachyarrhythmia, hypertensive emergency, and hemorrhagic and occlusive stroke. Ecstasy, 3,4 Methylenedioxymethamphetamin (MDMA with amphetamine like can

  16. Sulforaphane preconditioning of the Nrf2/HO-1 defense pathway protects the cerebral vasculature against blood-brain barrier disruption and neurological deficits in stroke.

    Science.gov (United States)

    Alfieri, Alessio; Srivastava, Salil; Siow, Richard C M; Cash, Diana; Modo, Michel; Duchen, Michael R; Fraser, Paul A; Williams, Steven C R; Mann, Giovanni E

    2013-12-01

    Disruption of the blood-brain barrier (BBB) and cerebral edema are the major pathogenic mechanisms leading to neurological dysfunction and death after ischemic stroke. The brain protects itself against infarction via activation of endogenous antioxidant defense mechanisms, and we here report the first evidence that sulforaphane-mediated preactivation of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream target heme oxygenase-1 (HO-1) in the cerebral vasculature protects the brain against stroke. To induce ischemic stroke, Sprague-Dawley rats were subjected to 70 min middle cerebral artery occlusion (MCAo) followed by 4, 24, or 72 h reperfusion. Nrf2 and HO-1 protein expression was upregulated in cerebral microvessels of peri-infarct regions after 4-72 h, with HO-1 preferentially associated with perivascular astrocytes rather than the cerebrovascular endothelium. In naïve rats, treatment with sulforaphane increased Nrf2 expression in cerebral microvessels after 24h. Upregulation of Nrf2 by sulforaphane treatment prior to transient MCAo (1h) was associated with increased HO-1 expression in perivascular astrocytes in peri-infarct regions and cerebral endothelium in the infarct core. BBB disruption, lesion progression, as analyzed by MRI, and neurological deficits were reduced by sulforaphane pretreatment. As sulforaphane pretreatment led to a moderate increase in peroxynitrite generation, we suggest that hormetic preconditioning underlies sulforaphane-mediated protection against stroke. In conclusion, we propose that pharmacological or dietary interventions aimed to precondition the brain via activation of the Nrf2 defense pathway in the cerebral microvasculature provide a novel therapeutic approach for preventing BBB breakdown and neurological dysfunction in stroke. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  17. Neuroprotective effect of pretreatment with Lavandula officinalis ethanolic extract on blood-brain barrier permeability in a rat stroke model.

    Science.gov (United States)

    Rabiei, Zahra; Rafieian-Kopaei, Mahmoud

    2014-09-01

    To evaluate the protective effect of Lavandula officinalis (L. officinalis) extract against blood-brain barrier (BBB) permeability and its possible mechanisms in an experimental model of stroke. Focal cerebral ischemia was induced by the transient occlusion of the middle cerebral artery for 1 h in rats. Lavender extract (100, 200 mg/kg i.p.) was injected for 20 consecutive days. BBB permeability and oxidative stress biomarkers were evaluated using standard methods. The results of this study showed that L. officinalis ethanolic extract significantly reduced the BBB permeability in experimental groups when compared with ischemia group. The lavender extract significantly reduced malondialdehyde levels of plasma and brain tissue in intact group when compared with control group. L. officinalis extract reduced blood brain barrier permeability and alleviated neurological function in rats, and the mechanism may be related to augmentation in endogenous antioxidant defense and inhibition of oxidative stress in the rat brain. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  18. Preservation of structural brain network hubs is associated with less severe post-stroke aphasia.

    Science.gov (United States)

    Gleichgerrcht, Ezequiel; Kocher, Madison; Nesland, Travis; Rorden, Chris; Fridriksson, Julius; Bonilha, Leonardo

    2015-01-01

    Post-stroke aphasia is typically associated with ischemic damage to cortical areas or with loss of connectivity among spared brain regions. It remains unclear whether the participation of spared brain regions as networks hubs affects the severity of aphasia. We evaluated language performance and magnetic resonance imaging from 44 participants with chronic aphasia post-stroke. The individual structural brain connectomes were constructed from diffusion tensor. Hub regions were defined in accordance with the rich club classification and studied in relation with language performance. Number of remaining left hemisphere rich club nodes was associated with aphasia, including comprehension, repetition and naming sub-scores. Importantly, among participants with relative preservation of regions of interest for language, aphasia severity was lessened if the region was not only spared, but also participated in the remaining network as a rich club node: Brodmann area (BA) 44/45 - repetition (p = 0.009), BA 39 - repetition (p = 0.045) and naming (p hubs is directly associated with aphasia severity after stroke.

  19. Hyper-attenuating brain lesions on CT after ischemic stroke and thrombectomy are associated with final brain infarction.

    Science.gov (United States)

    Cabral, F B; Castro-Afonso, L H; Nakiri, G S; Monsignore, L M; Fábio, Src; Dos Santos, A C; Pontes-Neto, O M; Abud, D G

    2017-12-01

    Purpose Hyper-attenuating lesions, or contrast staining, on a non-contrast brain computed tomography (NCCT) scan have been investigated as a predictor for hemorrhagic transformation after endovascular treatment of acute ischemic stroke (AIS). However, the association of hyper-attenuating lesions and final ischemic areas are poorly investigated in this setting. The aim of the present study was to assess correlations between hyper-attenuating lesions and final brain infarcted areas after thrombectomy for AIS. Methods Data from patients with AIS of the anterior circulation who underwent endovascular treatment were retrospectively assessed. Images of the brain NCCT scans were analyzed in the first hours and late after treatment. The hyper-attenuating areas were compared to the final ischemic areas using the Alberta Stroke Program Early CT Score (ASPECTS). Results Seventy-one of the 123 patients (65.13%) treated were included. The association between the hyper-attenuating region in the post-thrombectomy CT scan and final brain ischemic area were sensitivity (58.3% to 96.9%), specificity (42.9% to 95.6%), positive predictive values (71.4% to 97.7%), negative predictive values (53.8% to 79.5%), and accuracy values (68% to 91%). The highest sensitivity values were found for the lentiform (96.9%) and caudate nuclei (80.4%) and for the internal capsule (87.5%), and the lowest values were found for the M1 (58.3%) and M6 (66.7%) cortices. Conclusions Hyper-attenuating lesions on head NCCT scans performed after endovascular treatment of AIS may predict final brain infarcted areas. The prediction appears to be higher in the deep brain regions compared with the cortical regions.

  20. Brain Stroke Detection by Microwaves Using Prior Information from Clinical Databases

    Directory of Open Access Journals (Sweden)

    Natalia Irishina

    2013-01-01

    Full Text Available Microwave tomographic imaging is an inexpensive, noninvasive modality of media dielectric properties reconstruction which can be utilized as a screening method in clinical applications such as breast cancer and brain stroke detection. For breast cancer detection, the iterative algorithm of structural inversion with level sets provides well-defined boundaries and incorporates an intrinsic regularization, which permits to discover small lesions. However, in case of brain lesion, the inverse problem is much more difficult due to the skull, which causes low microwave penetration and highly noisy data. In addition, cerebral liquid has dielectric properties similar to those of blood, which makes the inversion more complicated. Nevertheless, the contrast in the conductivity and permittivity values in this situation is significant due to blood high dielectric values compared to those of surrounding grey and white matter tissues. We show that using brain MRI images as prior information about brain's configuration, along with known brain dielectric properties, and the intrinsic regularization by structural inversion, allows successful and rapid stroke detection even in difficult cases. The method has been applied to 2D slices created from a database of 3D real MRI phantom images to effectively detect lesions larger than 2.5 × 10−2 m diameter.

  1. A Randomized Controlled Trial of EEG-Based Motor Imagery Brain-Computer Interface Robotic Rehabilitation for Stroke.

    Science.gov (United States)

    Ang, Kai Keng; Chua, Karen Sui Geok; Phua, Kok Soon; Wang, Chuanchu; Chin, Zheng Yang; Kuah, Christopher Wee Keong; Low, Wilson; Guan, Cuntai

    2015-10-01

    Electroencephalography (EEG)-based motor imagery (MI) brain-computer interface (BCI) technology has the potential to restore motor function by inducing activity-dependent brain plasticity. The purpose of this study was to investigate the efficacy of an EEG-based MI BCI system coupled with MIT-Manus shoulder-elbow robotic feedback (BCI-Manus) for subjects with chronic stroke with upper-limb hemiparesis. In this single-blind, randomized trial, 26 hemiplegic subjects (Fugl-Meyer Assessment of Motor Recovery After Stroke [FMMA] score, 4-40; 16 men; mean age, 51.4 years; mean stroke duration, 297.4 days), prescreened with the ability to use the MI BCI, were randomly allocated to BCI-Manus or Manus therapy, lasting 18 hours over 4 weeks. Efficacy was measured using upper-extremity FMMA scores at weeks 0, 2, 4 and 12. ElEG data from subjects allocated to BCI-Manus were quantified using the revised brain symmetry index (rBSI) and analyzed for correlation with the improvements in FMMA score. Eleven and 15 subjects underwent BCI-Manus and Manus therapy, respectively. One subject in the Manus group dropped out. Mean total FMMA scores at weeks 0, 2, 4, and 12 weeks improved for both groups: 26.3±10.3, 27.4±12.0, 30.8±13.8, and 31.5±13.5 for BCI-Manus and 26.6±18.9, 29.9±20.6, 32.9±21.4, and 33.9±20.2 for Manus, with no intergroup differences (P=.51). More subjects attained further gains in FMMA scores at week 12 from BCI-Manus (7 of 11 [63.6%]) than Manus (5 of 14 [35.7%]). A negative correlation was found between the rBSI and FMMA score improvement (P=.044). BCI-Manus therapy was well tolerated and not associated with adverse events. In conclusion, BCI-Manus therapy is effective and safe for arm rehabilitation after severe poststroke hemiparesis. Motor gains were comparable to those attained with intensive robotic therapy (1,040 repetitions/session) despite reduced arm exercise repetitions using EEG-based MI-triggered robotic feedback (136 repetitions/session). The

  2. Radiation-induced brain injury: A review

    International Nuclear Information System (INIS)

    Greene-Schloesser, Dana; Robbins, Mike E.; Peiffer, Ann M.; Shaw, Edward G.; Wheeler, Kenneth T.; Chan, Michael D.

    2012-01-01

    Approximately 100,000 primary and metastatic brain tumor patients/year in the US survive long enough (>6 months) to experience radiation-induced brain injury. Prior to 1970, the human brain was thought to be highly radioresistant; the acute CNS syndrome occurs after single doses >30 Gy; white matter necrosis occurs at fractionated doses >60 Gy. Although white matter necrosis is uncommon with modern techniques, functional deficits, including progressive impairments in memory, attention, and executive function have become important, because they have profound effects on quality of life. Preclinical studies have provided valuable insights into the pathogenesis of radiation-induced cognitive impairment. Given its central role in memory and neurogenesis, the majority of these studies have focused on the hippocampus. Irradiating pediatric and young adult rodent brains leads to several hippocampal changes including neuroinflammation and a marked reduction in neurogenesis. These data have been interpreted to suggest that shielding the hippocampus will prevent clinical radiation-induced cognitive impairment. However, this interpretation may be overly simplistic. Studies using older rodents, that more closely match the adult human brain tumor population, indicate that, unlike pediatric and young adult rats, older rats fail to show a radiation-induced decrease in neurogenesis or a loss of mature neurons. Nevertheless, older rats still exhibit cognitive impairment. This occurs in the absence of demyelination and/or white matter necrosis similar to what is observed clinically, suggesting that more subtle molecular, cellular and/or microanatomic modifications are involved in this radiation-induced brain injury. Given that radiation-induced cognitive impairment likely reflects damage to both hippocampal- and non-hippocampal-dependent domains, there is a critical need to investigate the microanatomic and functional effects of radiation in various brain regions as well as their

  3. Changes in Electroencephalography Complexity using a Brain Computer Interface-Motor Observation Training in Chronic Stroke Patients: A Fuzzy Approximate Entropy Analysis

    Directory of Open Access Journals (Sweden)

    Rui Sun

    2017-09-01

    Full Text Available Entropy-based algorithms have been suggested as robust estimators of electroencephalography (EEG predictability or regularity. This study aimed to examine possible disturbances in EEG complexity as a means to elucidate the pathophysiological mechanisms in chronic stroke, before and after a brain computer interface (BCI-motor observation intervention. Eleven chronic stroke subjects and nine unimpaired subjects were recruited to examine the differences in their EEG complexity. The BCI-motor observation intervention was designed to promote functional recovery of the hand in stroke subjects. Fuzzy approximate entropy (fApEn, a novel entropy-based algorithm designed to evaluate complexity in physiological systems, was applied to assess the EEG signals acquired from unimpaired subjects and stroke subjects, both before and after training. The results showed that stroke subjects had significantly lower EEG fApEn than unimpaired subjects (p < 0.05 in the motor cortex area of the brain (C3, C4, FC3, FC4, CP3, and CP4 in both hemispheres before training. After training, motor function of the paretic upper limb, assessed by the Fugl-Meyer Assessment-Upper Limb (FMA-UL, Action Research Arm Test (ARAT, and Wolf Motor Function Test (WMFT improved significantly (p < 0.05. Furthermore, the EEG fApEn in stroke subjects increased considerably in the central area of the contralesional hemisphere after training (p < 0.05. A significant correlation was noted between clinical scales (FMA-UL, ARAT, and WMFT and EEG fApEn in C3/C4 in the contralesional hemisphere (p < 0.05. This finding suggests that the increase in EEG fApEn could be an estimator of the variance in upper limb motor function improvement. In summary, fApEn can be used to identify abnormal EEG complexity in chronic stroke, when used with BCI-motor observation training. Moreover, these findings based on the fApEn of EEG signals also expand the existing interpretation of training-induced functional

  4. Brain hemorrhage after endovascular reperfusion therapy of ischemic stroke: a threshold-finding whole-brain perfusion CT study

    Science.gov (United States)

    Renú, Arturo; Laredo, Carlos; Tudela, Raúl; Urra, Xabier; Lopez-Rueda, Antonio; Llull, Laura; Oleaga, Laura; Chamorro, Ángel

    2015-01-01

    Endovascular reperfusion therapy is increasingly used for acute ischemic stroke treatment. The occurrence of parenchymal hemorrhage is clinically relevant and increases with reperfusion therapies. Herein we aimed to examine the optimal perfusion CT-derived parameters and the impact of the duration of brain ischemia for the prediction of parenchymal hemorrhage after endovascular therapy. A cohort of 146 consecutive patients with anterior circulation occlusions and treated with endovascular reperfusion therapy was analyzed. Recanalization was assessed at the end of reperfusion treatment, and the rate of parenchymal hemorrhage at follow-up neuroimaging. In regression analyses, cerebral blood volume and cerebral blood flow performed better than Delay Time maps for the prediction of parenchymal hemorrhage. The most informative thresholds (receiver operating curves) for relative cerebral blood volume and relative cerebral blood flow were values lower than 2.5% of normal brain. In binary regression analyses, the volume of regions with reduced relative cerebral blood volume and/or relative cerebral blood flow was significantly associated with an increased risk of parenchymal hemorrhage, as well as delayed vessel recanalization. These results highlight the relevance of the severity and duration of ischemia as drivers of blood-brain barrier disruption in acute ischemic stroke and support the role of perfusion CT for the prediction of parenchymal hemorrhage. PMID:26661254

  5. Role of brain natriuretic peptide as a novel prognostic biomarker in acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    Bindu Menon

    2016-01-01

    Full Text Available Aim: We investigated to study the prognostic importance of brain natriuretic peptide (BNP in ischemic stroke. Materials and Methods: We prospectively enrolled 100 patients with acute ischemic stroke and measured plasma BNP levels and compared with age- and sex-matched healthy controls. Risk factors, biochemical parameters, lipid profile, carotid and vertebral Doppler, imaging, and cardiac evaluation were done. Stroke severity was assessed by the National Institutes of Health Stroke Scale (NIHSS score on admission and functional disability by Barthel Index (BI at 3 months. Ischemic stroke subtype was classified according to the Oxfordshire Community Stroke Project (OCSP. Data were entered in MS Excel, and appropriate statistical analysis was done using the SPSS software version 21.0. A P = 0.05 was considered as significant. Results: Mean age of patients was 55.17 ± 11.37 years with a male:female ratio 3:1. OCSP showed total anterior circulation infarct (TACI 35, partial anterior circulation infarct 9, lacunar infarct 12, and posterior circulation infarct 44. NIHSS on admission was average 10 ± 7 and BI was 57 ± 30. BNP in patients (435 ng/ml was very high as compared to controls (<60 ng/ml (P < 0.001. There was a positive correlation between age and BNP (R2 = 0.34; P < 0.00; NIHSS and BNP (R2 = 0.255; P < 0.01, negative correlation between BI and BNP (R2 = −0.064; P < 0.01. Mean BNP levels across the OCSP showed higher values in TACI (F = 4.609 P = 0.005. Regression analysis showed that BNP can predict BI which was statistically significant. Conclusion: Plasma BNP levels was significantly elevated in patients with ischemic stroke. Our study concludes that high BNP levels are seen in large anterior circulation stroke and is a predictor for the poor functional outcome at 3 months. Determination of BNP levels as a biomarker could be helpful in predicting the outcome in stroke patients.

  6. Totarol prevents neuronal injury in vitro and ameliorates brain ischemic stroke: Potential roles of Akt activation and HO-1 induction

    International Nuclear Information System (INIS)

    Gao, Yuanxue; Xu, Xiaojun; Chang, Sai; Wang, Yunjie; Xu, Yazhou; Ran, Siqi; Huang, Zhangjian; Li, Ping; Li, Jia; Zhang, Luyong; Saavedra, Juan M.; Liao, Hong; Pang, Tao

    2015-01-01

    Totarol activates PI3K/Akt pathway in neurons. • Totarol induces HO-1, GSH and SOD expression in vitro and in vivo. • Totarol exhibits neuroprotective effects in rat brain ischemic stroke model.

  7. Know your tools - concordance of different methods for measuring brain volume change after ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Yassi, Nawaf; Campbell, Bruce C.V.; Davis, Stephen M.; Bivard, Andrew [The University of Melbourne, Departments of Medicine and Neurology, Melbourne Brain Centre rate at The Royal Melbourne Hospital, Parkville, Victoria (Australia); Moffat, Bradford A.; Steward, Christopher; Desmond, Patricia M. [The University of Melbourne, Department of Radiology, The Royal Melbourne Hospital, Parkville (Australia); Churilov, Leonid [The University of Melbourne, The Florey Institute of Neurosciences and Mental Health, Parkville (Australia); Parsons, Mark W. [University of Newcastle and Hunter Medical Research Institute, Priority Research Centre for Translational Neuroscience and Mental Health, Newcastle (Australia)

    2015-07-15

    Longitudinal brain volume changes have been investigated in a number of cerebral disorders as a surrogate marker of clinical outcome. In stroke, unique methodological challenges are posed by dynamic structural changes occurring after onset, particularly those relating to the infarct lesion. We aimed to evaluate agreement between different analysis methods for the measurement of post-stroke brain volume change, and to explore technical challenges inherent to these methods. Fifteen patients with anterior circulation stroke underwent magnetic resonance imaging within 1 week of onset and at 1 and 3 months. Whole-brain as well as grey- and white-matter volume were estimated separately using both an intensity-based and a surface watershed-based algorithm. In the case of the intensity-based algorithm, the analysis was also performed with and without exclusion of the infarct lesion. Due to the effects of peri-infarct edema at the baseline scan, longitudinal volume change was measured as percentage change between the 1 and 3-month scans. Intra-class and concordance correlation coefficients were used to assess agreement between the different analysis methods. Reduced major axis regression was used to inspect the nature of bias between measurements. Overall agreement between methods was modest with strong disagreement between some techniques. Measurements were variably impacted by procedures performed to account for infarct lesions. Improvements in volumetric methods and consensus between methodologies employed in different studies are necessary in order to increase the validity of conclusions derived from post-stroke cerebral volumetric studies. Readers should be aware of the potential impact of different methods on study conclusions. (orig.)

  8. Repeated sessions of noninvasive brain DC stimulation is associated with motor function improvement in stroke patients.

    Science.gov (United States)

    Boggio, Paulo S; Nunes, Alice; Rigonatti, Sergio P; Nitsche, Michael A; Pascual-Leone, Alvaro; Fregni, Felipe

    2007-01-01

    Recent evidence has suggested that a simple technique of noninvasive brain stimulation - transcranial direct current stimulation (tDCS) - is associated with a significant motor function improvement in stroke patients. We tested the motor performance improvement in stroke patients following 4 weekly sessions of sham, anodal- and cathodal tDCS (experiment 1) and the effects of 5 consecutive daily sessions of cathodal tDCS (experiment 2). A blinded rater evaluated motor function using the Jebsen-Taylor Hand Function Test. There was a significant main effect of stimulation condition (p=0.009) in experiment 1. Furthermore there was a significant motor function improvement after either cathodal tDCS of the unaffected hemisphere (p=0.016) or anodal tDCS of the affected hemisphere (p=0.046) when compared to sham tDCS. There was no cumulative effect associated with weekly sessions of tDCS, however consecutive daily sessions of tDCS (experiment 2) were associated with a significant effect on time (pmotor function improvement in stroke patients; and support that consecutive daily sessions of tDCS might increase its behavioral effects. Because the technique of tDCS is simple, safe and non-expensive; our findings support further research on the use of this technique for the rehabilitation of patients with stroke.

  9. [Polymorphism of brain derived neurotrophic factor and recovery of functions after ischemic stroke].

    Science.gov (United States)

    Liepert, J; Heller, A; Behnisch, G; Schoenfeld, A

    2015-10-01

    After ischemic stroke, many factors influence the restitution of functions. In particular they include the patient age, the initial stroke severity and the presence of cognitive and neuropsychological deficits. In this study we investigated whether a polymorphism in the gene encoding for brain derived neurotrophic factor (BDNF) influences improvements of motor functions and everyday activities. Patients with subacute ischemic stroke (n = 67) were examined at the beginning of an inpatient neurological rehabilitation, after 4 weeks of treatment and after 6 months. The Barthel index (BI) and the Rivermead motor assessment (RMA) were used to measure motor functions and everyday activities. Patients were allocated to three groups (valine [Val]/valine, val/methionine [Met] and Met/Met) depending on the BDNF polymorphism at codon 66. The 3 groups (Val/Val, n = 34 patients, Val/Met, n = 26 and Met/Met, n = 7) showed significant improvements in BI and RMA after 4 weeks and after 6 months as compared to the preceding measurements. The BI and RMA were positively correlated. The three groups did not differ with respect to the extent of improvement. After ischemic stroke, motor functions and everyday activities improved continuously over a period of at least 6 months. The BDNF polymorphism did not influence this development.

  10. Overexpression of brain-derived neurotrophic factor in the hippocampus protects against post-stroke depression

    Directory of Open Access Journals (Sweden)

    Hao-hao Chen

    2015-01-01

    Full Text Available Post-stroke depression is associated with reduced expression of brain-derived neurotrophic factor (BDNF. In this study, we evaluated whether BDNF overexpression affects depression-like behavior in a rat model of post-stroke depression. The middle cerebral artery was occluded to produce a model of focal cerebral ischemia. These rats were then subjected to isolation-housing combined with chronic unpredictable mild stress to generate a model of post-stroke depression. A BDNF gene lentiviral vector was injected into the hippocampus. At 7 days after injection, western blot assay and real-time quantitative PCR revealed that BDNF expression in the hippocampus was increased in depressive rats injected with BDNF lentivirus compared with depressive rats injected with control vector. Furthermore, sucrose solution consumption was higher, and horizontal and vertical movement scores were increased in the open field test in these rats as well. These findings suggest that BDNF overexpression in the hippocampus of post-stroke depressive rats alleviates depression-like behaviors.

  11. Early Blood-Brain Barrier Disruption after Mechanical Thrombectomy in Acute Ischemic Stroke.

    Science.gov (United States)

    Shi, Zhong-Song; Duckwiler, Gary R; Jahan, Reza; Tateshima, Satoshi; Szeder, Viktor; Saver, Jeffrey L; Kim, Doojin; Sharma, Latisha K; Vespa, Paul M; Salamon, Noriko; Villablanca, J Pablo; Viñuela, Fernando; Feng, Lei; Loh, Yince; Liebeskind, David S

    2018-02-27

    The impact of blood-brain barrier (BBB) disruption can be detected by intraparenchymal hyperdense lesion on the computed tomography (CT) scan after endovascular stroke therapy. The purpose of this study was to determine whether early BBB disruption predicts intracranial hemorrhage and poor outcome in patients with acute ischemic stroke treated with mechanical thrombectomy. We analyzed patients with anterior circulation stroke treated with mechanical thrombectomy and identified BBB disruption on the noncontrast CT images immediately after endovascular treatment. Follow-up CT or magnetic resonance imaging scan was performed at 24 hours to assess intracranial hemorrhage. We dichotomized patients into those with moderate BBB disruption versus those with minor BBB disruption and no BBB disruption. We evaluated the association of moderate BBB disruption after mechanical thrombectomy with intracranial hemorrhage and clinical outcomes. Moderate BBB disruption after mechanical thrombectomy was found in 56 of 210 patients (26.7%). Moderate BBB disruption was independently associated with higher rates of hemorrhagic transformation (OR 25.33; 95% CI 9.93-64.65; P disruption with intracranial hemorrhage remained in patients with successful reperfusion after mechanical thrombectomy. The location of BBB disruption was not associated with intracranial hemorrhage and poor outcome. Moderate BBB disruption is common after mechanical thrombectomy in a quarter of patients with acute ischemic stroke and increases the risk of intracranial hemorrhage and poor outcome. Copyright © 2018 by the American Society of Neuroimaging.

  12. Participation of MCP-induced protein 1 in lipopolysaccharide preconditioning-induced ischemic stroke tolerance by regulating the expression of proinflammatory cytokines

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    Liang Jian

    2011-12-01

    Full Text Available Abstract Background Lipopolysaccharide (LPS preconditioning-induced neuroprotection is known to be related to suppression of the inflammatory response in the ischemic area. This study seeks to determine if monocyte chemotactic protein-induced protein 1 (MCPIP1, a recently identified CCCH Zn finger-containing protein, plays a role in focal brain ischemia and to elucidate the mechanisms of LPS-induced ischemic brain tolerance. Methods Transcription and expression of MCPIP1 gene was monitored by qRT-PCR and Western blot. Mouse microglia was prepared from cortices of C57BL/6 mouse brain and primary human microglia was acquired from Clonexpress, Inc. Wild type and MCPIP1 knockout mice were treated with LPS (0.2 mg/kg 24 hours before brain ischemia induced by transient middle cerebral artery occlusion (MCAO. The infarct was measured by 2,3,5-triphenyltetrazolium chloride (TTC staining. Results MCPIP1 protein and mRNA levels significantly increased in both mouse and human microglia and mouse brain undergoing LPS preconditioning. MCPIP1 mRNA level significantly increased in mice ipsilateral brain than that of contralateral side after MCAO. The mortality of MCPIP1 knockout mice was significantly higher than that of wild-type after MCAO. MCPIP1 deficiency caused significant increase in the infarct volume compared with wild type mice undergoing LPS preconditioning. MCPIP1 deficiency caused significant upregulation of proinflammatory cytokines in mouse brain. Furthermore, MCPIP1 deficiency increased c-Jun N terminal kinase (JNK activation substantially. Inhibition of JNK signaling decreased the production of proinflammatory cytokines in MCPIP1 knock out mice after MCAO. Conclusions Our data indicate that absence of MCPIP1 exacerbates ischemic brain damage by upregulation of proinflammatory cytokines and that MCPIP1 participates in LPS-induced ischemic stroke tolerance.

  13. Obesity-Induced Hypertension: Brain Signaling Pathways

    Science.gov (United States)

    da Silva, Alexandre A.; Wang, Zhen; Fang, Taolin; Aberdein, Nicola; de Lara Rodriguez, Cecilia E. P.; Hall, John E.

    2017-01-01

    Obesity greatly increases the risk for cardiovascular, metabolic, and renal diseases and is one of the most significant and preventable causes of increased blood pressure (BP) in patients with essential hypertension. This review high-lights recent advances in our understanding of central nervous system (CNS) signaling pathways that contribute to the etiology and pathogenesis of obesity-induced hypertension. We discuss the role of excess adiposity and activation of the brain leptin-melanocortin system in causing increased sympathetic activity in obesity. In addition, we highlight other potential brain mechanisms by which increased weight gain modulates metabolic and cardiovascular functions. Unraveling the CNS mechanisms responsible for increased sympathetic activation and hypertension and how circulating hormones activate brain signaling pathways to control BP offer potentially important therapeutic targets for obesity and hypertension. PMID:27262997

  14. [Higher Brain Dysfunction in Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis and Stroke-Like Episodes (MELAS)].

    Science.gov (United States)

    Ichikawa, Hiroo

    2016-02-01

    Stroke-like episodes are one of the cardinal features of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), and occur in 84-99% of the patients. The affected areas detected on neuroimaging do not have classical vascular distribution, and involve predominantly the temporal, parietal and occipital lobes. Thus, the neurological symptoms including higher brain dysfunction correlate with this topographical distribution. In association with the occipital lobe involvement, the most frequent symptom is cortical blindness. Other symptoms have been occasionally reported in case reports: visual agnosia, prosopagnosia, cortical deafness, auditory agnosia, topographical disorientation, various types of aphasia, hemispatial neglect, and so on. On the other hand, cognitive decline associated with more diffuse brain impairment rather than with focal stroke-like lesions has been postulated. This condition is also known as mitochondrial dementia. Domains of cognitive dysfunction include abstract reasoning, verbal memory, visual memory, language (naming and fluency), executive or constructive functions, attention, and visuospatial function. Cognitive functions and intellectual abilities may decline from initially minimal cognitive impairment to dementia. To date, the neuropsychological and neurologic impairment has been reported to be associated with cerebral lactic acidosis as estimated by ventricular spectroscopic lactate levels.

  15. Deficiency of brain structural sub-network underlying post-ischaemic stroke apathy.

    Science.gov (United States)

    Yang, S; Hua, P; Shang, X; Cui, Z; Zhong, S; Gong, G; William Humphreys, G

    2015-02-01

    This study aimed to reveal the structural basis of post-ischaemic stroke apathy, especially in relation to disruptions in structural connectivity. Eighty-eight participants were included. The Apathy Evaluation Scale, clinician version, was used to characterize the severity of apathy. Diffusion tensor imaging tractography was used to examine white matter integrity and to reconstruct white matter networks using 90 nodes based on the automated anatomical labeling atlas. The degree for each node was extracted to determine the relationship to the severity of apathy. Apathy was not significantly associated with damage to any single brain region. The degrees of 24 nodes (limbic system, three nodes; frontal lobe, six; basal ganglia, two; temporal lobe, three; parietal lobe, three; insula, two; occipital lobe, five) were significantly correlated to the Apathy Evaluation Scale scores. These 24 nodes constituted an apathy-related sub-network and its global and local efficiencies were negatively correlated with apathy levels (global, r = -0.54, P apathy (odds ratio 0.03, 95% confidence interval 0.01-0.04, P = 0.007). Efficiencies of the non-apathy-related sub-network (the remaining 66 nodes) did not correlate or predict the presence of apathy. Post-stroke apathy is not due to the dysfunction of a single region or circuit. Rather, it results from disconnection of a complex sub-network of brain regions. This provides new insights into the neuroanatomical basis of post-stroke apathy. © 2014 EAN.

  16. Identifying the brain regions associated with acute spasticity in patients diagnosed with an ischemic stroke.

    Science.gov (United States)

    Barlow, Susan J

    2016-06-01

    Spasticity is a common impairment found in patients that have been diagnosed with a stroke. Little is known about the pathophysiology of spasticity at the level of the brain. This retrospective study was performed to identify an association between the area of the brain affected by an ischemic stroke and the presence of acute spasticity. Physical and occupational therapy assessments from all patients (n = 441) that had suffered a stroke and were admitted into a local hospital over a 4-year period were screened for inclusion in this study. Subjects that fit the inclusion criteria were grouped according to the presence (n = 42) or absence (n = 129) of acute spasticity by the Modified Ashworth Scale score given during the hospital admission assessment. Magnetic resonance images from 20 subjects in the spasticity group and 52 from the control group were then compared using lesion density plots and voxel-based lesion-symptom mapping. An association of acute spasticity with the gray matter regions of the insula, basal ganglia, and thalamus was found in this study. White matter tracts including the pontine crossing tract, corticospinal tract, internal capsule, corona radiata, external capsule, and the superior fronto-occipital fasciculus were also found to be significantly associated with acute spasticity. This is the first study to describe an association between a region of the brain affected by an infarct and the presence of acute spasticity. Understanding the regions associated with acute spasticity will aid in understanding the pathophysiology of this musculoskeletal impairment at the level of the brain.

  17. Revised and updated recommendations for the establishment of primary stroke centers: a summary statement from the brain attack coalition.

    Science.gov (United States)

    Alberts, Mark J; Latchaw, Richard E; Jagoda, Andy; Wechsler, Lawrence R; Crocco, Todd; George, Mary G; Connolly, E S; Mancini, Barbara; Prudhomme, Stephen; Gress, Daryl; Jensen, Mary E; Bass, Robert; Ruff, Robert; Foell, Kathy; Armonda, Rocco A; Emr, Marian; Warren, Margo; Baranski, Jim; Walker, Michael D

    2011-09-01

    The formation and certification of Primary Stroke Centers has progressed rapidly since the Brain Attack Coalition's original recommendations in 2000. The purpose of this article is to revise and update our recommendations for Primary Stroke Centers to reflect the latest data and experience. We conducted a literature review using MEDLINE and PubMed from March 2000 to January 2011. The review focused on studies that were relevant for acute stroke diagnosis, treatment, and care. Original references as well as meta-analyses and other care guidelines were also reviewed and included if found to be valid and relevant. Levels of evidence were added to reflect current guideline development practices. Based on the literature review and experience at Primary Stroke Centers, the importance of some elements has been further strengthened, and several new areas have been added. These include (1) the importance of acute stroke teams; (2) the importance of Stroke Units with telemetry monitoring; (3) performance of brain imaging with MRI and diffusion-weighted sequences; (4) assessment of cerebral vasculature with MR angiography or CT angiography; (5) cardiac imaging; (6) early initiation of rehabilitation therapies; and (7) certification by an independent body, including a site visit and disease performance measures. Based on the evidence, several elements of Primary Stroke Centers are particularly important for improving the care of patients with an acute stroke. Additional elements focus on imaging of the brain, the cerebral vasculature, and the heart. These new elements may improve the care and outcomes for patients with stroke cared for at a Primary Stroke Center.

  18. DAMP signaling is a key pathway inducing immune modulation after brain injury.

    Science.gov (United States)

    Liesz, Arthur; Dalpke, Alexander; Mracsko, Eva; Antoine, Daniel J; Roth, Stefan; Zhou, Wei; Yang, Huan; Na, Shin-Young; Akhisaroglu, Mustafa; Fleming, Thomas; Eigenbrod, Tatjana; Nawroth, Peter P; Tracey, Kevin J; Veltkamp, Roland

    2015-01-14

    Acute brain lesions induce profound alterations of the peripheral immune response comprising the opposing phenomena of early immune activation and subsequent immunosuppression. The mechanisms underlying this brain-immune signaling are largely unknown. We used animal models for experimental brain ischemia as a paradigm of acute brain lesions and additionally investigated a large cohort of stroke patients. We analyzed release of HMGB1 isoforms by mass spectrometry and investigated its inflammatory potency and signaling pathways by immunological in vivo and in vitro techniques. Features of the complex behavioral sickness behavior syndrome were characterized by homecage behavior analysis. HMGB1 downstream signaling, particularly with RAGE, was studied in various transgenic animal models and by pharmacological blockade. Our results indicate that the cytokine-inducing, fully reduced isoform of HMGB1 was released from the ischemic brain in the hyperacute phase of stroke in mice and patients. Cytokines secreted in the periphery in response to brain injury induced sickness behavior, which could be abrogated by inhibition of the HMGB1-RAGE pathway or direct cytokine neutralization. Subsequently, HMGB1-release induced bone marrow egress and splenic proliferation of bone marrow-derived suppressor cells, inhibiting the adaptive immune responses in vivo and vitro. Furthermore, HMGB1-RAGE signaling resulted in functional exhaustion of mature monocytes and lymphopenia, the hallmarks of immune suppression after extensive ischemia. This study introduces the HMGB1-RAGE-mediated pathway as a key mechanism explaining the complex postischemic brain-immune interactions. Copyright © 2015 the authors 0270-6474/15/350583-16$15.00/0.

  19. Attenuating brain inflammation, ischemia, and oxidative damage by hyperbaric oxygen in diabetic rats after heat stroke

    Directory of Open Access Journals (Sweden)

    Kai-Li Lee

    2013-08-01

    Conclusion: Our results suggest that, in diabetic animals, HBO2 therapy may improve outcomes of HS in part by reducing heat-induced activated inflammation and ischemic and oxidative damage in the hypothalamus and other brain regions.

  20. BRAIN NATRIURETIC PEPTIDE (BNP: BIOMARKER FOR RISK STRATIFICATION AND FUNCTIONAL RECOVERY PREDICTION IN ISCHEMIC STROKE

    Directory of Open Access Journals (Sweden)

    STANESCU Ioana

    2015-02-01

    Full Text Available Functional outcome after cardiovascular and cerebrovascular events is traditionally predicted using demographic and clinical variables like age, gender, blood pressure, cholesterol levels, diabetes status, smoking habits or pre-existing morbidity. Identification of new variables will improve the risk stratification of specific categories of patients. Numerous blood-based biomarkers associated with increased cardiovascular risk have been identified; some of them even predict cardiovascular events. Investigators have tried to produce prediction models by incorporating traditional risk factors and biomarkers. (1. Widely-available, rapidly processed and less expensive biomarkers could be used in the future to guide management of complex cerebrovascular patients in order to maximize their recovery (2 Recently, studies have demonstrated that biomarkers can predict not only the risk for a specific clinical event, but also the risk of death of vascular cause and the functional outcome after cardiovascular or cerebrovascular events. Early prediction of fatal outcome after stroke may improve therapeutic strategies (such as the use of more aggressive treatments or inclusion of patients in clinical trials and guide decision-making processes in order to maximize patient’s chances for survival and recovery. (3 Long term functional outcome after stroke is one of the most difficult variables to predict. Elevated serum levels of brain natriuretic peptide (BNP are powerful predictor of outcomes in patients with cardiovascular disease (heart failure, atrial fibrillation. Potential role of BNP in predicting atrial fibrillation occurrence, cardio-embolic stroke and post-stroke mortality have been proved in many studies. However, data concerning the potential role of BNP in predicting short term and long term functional outcomes after stroke remain controversial.

  1. Association between Severe Upper Limb Spasticity and Brain Lesion Location in Stroke Patients

    Directory of Open Access Journals (Sweden)

    Alessandro Picelli

    2014-01-01

    Full Text Available Association between the site of brain injury and poststroke spasticity is poorly understood. The present study investigated whether lesion analysis could document brain regions associated with the development of severe upper limb poststroke spasticity. A retrospective analysis was conducted on 39 chronic stroke patients. Spasticity was assessed at the affected upper limb with the modified Ashworth scale (shoulder, elbow, wrist, and fingers. Brain lesions were traced from magnetic resonance imaging performed within the first 7 days after stroke and region of interest images were generated. The association between severe upper limb spasticity (modified Ashworth scale ≥2 and lesion location was determined with the voxel-based lesion-symptom mapping method implemented in MRIcro software. Colored maps representing the z statistics were generated and overlaid onto the automated anatomical labeling and the Johns Hopkins University white matter templates provided with MRIcron. Thalamic nuclei were identified with the Talairach Daemon software. Injuries to the insula, the thalamus, the basal ganglia, and white matter tracts (internal capsule, corona radiata, external capsule, and superior longitudinal fasciculus were significantly associated with severe upper limb poststroke spasticity. Further advances in our understanding of the neural correlates of spasticity may lead to early targeted rehabilitation when key regions are damaged.

  2. Assessment of brain perfusion with MRI: methodology and application to acute stroke

    International Nuclear Information System (INIS)

    Grandin, C.B.

    2003-01-01

    We review the methodology of brain perfusion measurements with MRI and their application to acute stroke, with particular emphasis on the work awarded by the 6th Lucien Appel Prize for Neuroradiology. The application of the indicator dilution theory to the dynamic susceptibility-weighted bolus-tracking method is explained, as is the approach to obtaining quantitative measurements of cerebral blood flow (CBF) and volume (CBV). Our contribution to methodological developments, such as CBV measurement with the frequency-shifted burst sequence, development of the PRESTO sequence, comparison of different deconvolution methods and of spin- and gradient-echo sequences, and the validation of MRI measurements against positron emission tomography is summarised. The pathophysiology of brain ischaemia and the role of neuroimaging in the setting of acute stroke are reviewed, with an introduction to the concepts of ischaemic penumbra and diffusion/perfusion mismatch. Our work on the determination of absolute CBF and CBV thresholds for predicting the area of infarct growth, identification of the best perfusion parameters (relative or absolute) for predicting the area of infarct growth and the role of MR angiography is also summarised. We conclude that MRI is a very powerful way to assess brain perfusion and that its use might help in selecting patients who will benefit most from treatment such as thrombolysis. (orig.)

  3. PELATIHAN MIRROR NEURON SYSTEM SAMA DENGAN PELATIHAN CONSTRAINT INDUCED MOVEMENT THERAPY DALAM MENINGKATKAN KEMAMPUAN FUNGSIONAL ANGGOTA GERAK ATAS PASIEN STROKE

    Directory of Open Access Journals (Sweden)

    Abdul chalik meidian

    2014-03-01

    Full Text Available Stroke is an interruption of blood vasculature system in the brain that causes suddenly neurological dysfunction, resulted in clinically brain tissue damage in a relatively long time period, decreased physical mobility and functional ability impaired of upper limb. The purpose of this study is to know an increasing in upper limb functional ability among stroke patients after mirror neuron system exercise and constraint induced movement therapy exercise and to know the comparison of both exercise. This study uses an experimental research with pre-test and post-test control group design. Number of samples of the first group is 13 patients given mirror neuron system exercise for 30-60 minutes , while the second group 13 patients were given constraint induced movement therapy exercise for 30-60 minutes. The research was conducted in 2 month period time. Each patient is taught a variety of upper limb functional ability in accordance with the operational concept guidance and patients were asked to repeat the exercise independently at home as directed. Measuring test of upper limb functional ability is using the wolf motor function test instruments. The result is an increase the upper limb functional ability of 21.7% in the mirror neuron system exercise group and proved a significant difference (p<0.05 and an increase in the upper limb functional ability of 17.1% in the constraint induced movement therapy exercise group and proved a significant difference (p<0.05 while the difference of increasing of upper limb functional ability of the two groups showed no significant difference (p>0,05. It was concluded that the mirror neuron system exercise is similar with constraint induced movement therapy exercise in increasing the upper limb functional ability among stroke patients.

  4. EFFECT OF MODIFIED CONSTRAINT INDUCED THERAPY ON UPPERLIMB FUNCTIONAL RECOVERY IN YOUNG STROKE SUBJECTS

    Directory of Open Access Journals (Sweden)

    Kiran Prakash Pappala

    2014-10-01

    Full Text Available Background: The aim of this study is to evaluate the effect of modified constraint induced therapy on upper limb functional recovery in young stroke subjects. Most of the stroke rehabilitation units following conventional rehabilitation methods for treatment of the stroke patients where these methods have been proved to be less useful especially in the young stroke subjects. Hence the purpose of this study is to see the effect of modified constraint induced therapy which is a task specific training method for upperlimb in young stroke subjects. Methods: Total of 40 young stroke subjects who is having minimal motor criterion and met other inclusion criteria were recruited from department of physiotherapy, g.s.l.general hospital. Pre and post intervention measures were taken using Wolf motor function test and Jebsen Taylor hand function test. Results: In this study had shown significant improvements in the modified constraint induced therapy group when compared to the conventional rehabilitation alone. P value between groups was < 0.05. Conclusion: In this study concludes that addition of 15 minutes modified constraint induced movement therapy to conventional physiotherapy is a useful adjunct in functional recovery of upper limb among young stroke subjects

  5. Diffusion tensor and volumetric magnetic resonance imaging using an MR-compatible hand-induced robotic device suggests training-induced neuroplasticity in patients with chronic stroke

    OpenAIRE

    LAZARIDOU, ASIMINA; ASTRAKAS, LOUKAS; MINTZOPOULOS, DIONYSSIOS; KHANICHEH, AZADEH; SINGHAL, ANEESH B.; MOSKOWITZ, MICHAEL A.; ROSEN, BRUCE; TZIKA, ARIA A.

    2013-01-01

    Stroke is the third leading cause of mortality and a frequent cause of long-term adult impairment. Improved strategies to enhance motor function in individuals with chronic disability from stroke are thus required. Post-stroke therapy may improve rehabilitation and reduce long-term disability; however, objective methods for evaluating the specific impact of rehabilitation are rare. Brain imaging studies on patients with chronic stroke have shown evidence for reorganization of areas showing fu...

  6. Relationship between Brain Lesion Location and Aphasia Type in Persian Speaking Patients with Stroke

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    Hossein Rezai

    2011-01-01

    Full Text Available Objective: It has been many years that brain lesion analysis of different aphasia Syndromes has led the foundation to investigate the language representation and organization in the brain. The aim of this study was to examine the relationship between brain lesion location and Broca's aphasia and Wernecke's aphasia in Persian speakers with stroke. Materials & Methods: In a single system design study, from 120 patients with stroke attending Emam Khomeyni and Loghman hospitals, Rofeyde, Karaj neurology, and Tabassom speech clinics and according to the Farsi Aphasia Test (FAT, syntactic comprehension subscale of Bilingual Aphasia Test (BAT, Farsi Aphasia Naming Test, and Apraxia Assessment inventory, only 9 patients with Broca’s aphasia and 2 with Wernicke’s aphasia were qualified to participate in this study. Patients’ brain lesion sites were determined by MRI. Patients with Broca’s aphasia were 5 male and 4 female Wernecke’s aphasia patients were 2 male. Results: External capsule-insula, rolandic operculum, inferior frontal gyrus, (precentral gyrus and postcentarl gyrus, and the anterior part of temporal gyrus were damaged in Broca’s aphasia patients (64±12.51 years old and the lesions of external capsule-insula, posterior part of temporal gyrus, anterior part of temporal gyrus, inferior parietal lobule were observed in Wernicke’s aphasia patients (66±8.48 years old. Conclusion: In no patient with Broca’s aphasia or Wernicke’s aphasia brain lesion confined only to Broca’s area or Wernicke’s area respectively. However, due to the limited number of participants in the present study, the extrapolation of the findings to other subjects with Broca’s or Wernicke’s aphasia would certainly be difficult.

  7. Comprehensive regional and temporal gene expression profiling of the rat brain during the first 24 h after experimental stroke identifies dynamic ischemia-induced gene expression patterns, and reveals a biphasic activation of genes in surviving tissue

    DEFF Research Database (Denmark)

    Rickhag, Karl Mattias; Wieloch, Tadeusz; Gidö, Gunilla

    2006-01-01

    middle cerebral artery occlusion in the rat. K-means cluster analysis revealed two distinct biphasic gene expression patterns that contained 44 genes (including 18 immediate early genes), involved in cell signaling and plasticity (i.e. MAP2K7, Sprouty2, Irs-2, Homer1, GPRC5B, Grasp). The first gene...... induction phase occurred at 0-3 h of reperfusion, and the second at 9-15 h, and was validated by in situ hybridization. Four gene clusters displayed a progressive increase in expression over time and included 50 genes linked to cell motility, lipid synthesis and trafficking (i.e. ApoD, NPC1, G3P...... tissue, concomitant with a progressive and persistent activation of cell proliferation signifying tissue regeneration, which provide the means for cell survival and postischemic brain plasticity....

  8. Routine physiotherapy does not induce a cardiorespiratory training effect post-stroke, regardless of walking ability.

    Science.gov (United States)

    Kuys, Suzanne; Brauer, Sandra; Ada, Louise

    2006-12-01

    Cardiorespiratory fitness is increasingly being recognized as an impairment requiring physiotherapy intervention after stroke. The present study seeks to investigate if routine physiotherapy treatment is capable of inducing a cardiorespiratory training effect and if stroke patients attending physiotherapy who are unable to walk experience less cardiorespiratory stress during physiotherapy when compared to those who are able to walk. A descriptive, observational study, with heart rate monitoring and video-recording of physiotherapy rehabilitation, was conducted. Thirty consecutive stroke patients from a geriatric and rehabilitation unit of a tertiary metropolitan hospital, admitted for rehabilitation, and requiring physiotherapy were included in the study. The main measures of the study were duration (time) and intensity (percentage of heart rate reserve) of standing and walking activities during physiotherapy rehabilitation for non-walking and walking stroke patients. Stroke patients spent an average of 21 minutes participating in standing and walking activities that were capable of inducing a cardiorespiratory training effect. Stroke patients who were able to walk spent longer in these activities during physiotherapy rehabilitation than non-walking stroke patients (p physiotherapy rehabilitation had insufficient duration and intensity to result in a cardiorespiratory training effect in our group of stroke patients.

  9. Evaluation of differences in brain neurophysiology and morphometry associated with hand function in individuals with chronic stroke.

    Science.gov (United States)

    Borich, Michael R; Neva, Jason L; Boyd, Lara A

    2015-01-01

    Rehabilitation interventions need to be optimized to maximize therapeutic effects and minimize stroke-related disability. However, a comprehensive understanding of the neural substrates underlying recovery is lacking. The purpose of this study was to investigate relationships between brain anatomy, physiology and hand motor function in individuals with chronic stroke. Transcranial magnetic stimulation (TMS) and magnetic resonance imaging (MRI) approaches were used to evaluate cortical excitability and brain structural morphometry in individuals with chronic stroke. Hemispheric differences and relationships between these measures and hand dexterity were evaluated. Hemispheric differences were observed for TMS and MRI measures. Bilateral hand dexterity correlated with TMS resting motor threshold and precentral gyral thickness. Transcallosal inhibition across hemispheres was positively associated with midcallosal white matter volume. Regression modeling results demonstrated that combining TMS and MRI measures predicted unique amounts of variance in hand dexterity. RESULTS confirm and extend findings showing differences in brain structure and function after stroke. RESULTS suggested a structure-function relationship underlying interhemispheric connectivity in chronic stroke. The utility of combined TMS and MRI measures to predict motor function can be used in future investigations to aid identifying optimal biomarkers of stroke recovery to predict response to rehabilitation to maximize treatment outcomes.

  10. Characteristics of Dysphagia in Severe Traumatic Brain Injury Patients: A Comparison With Stroke Patients.

    Science.gov (United States)

    Lee, Won Kyung; Yeom, Jiwoon; Lee, Woo Hyung; Seo, Han Gil; Oh, Byung-Mo; Han, Tai Ryoon

    2016-06-01

    To compare the swallowing characteristics of dysphagic patients with traumatic brain injury (TBI) with those of dysphagic stroke patients. Forty-one patients with TBI were selected from medical records (between December 2004 to March 2013) and matched to patients with stroke (n=41) based on age, sex, and disease duration. Patients' swallowing characteristics were analyzed retrospectively using a videofluoroscopic swallowing study (VFSS) and compared between both groups. Following thorough review of medical records, patients who had a history of diseases that could affect swallowing function at the time of the study were excluded. Dysphagia characteristics and severity were evaluated using the American Speech-Language-Hearing Association National Outcome Measurement System swallowing scale, clinical dysphagia scale, and the videofluoroscopic dysphagia scale. There was a significant difference in radiological lesion location (p=0.024) between the two groups. The most common VFSS finding was aspiration or penetration, followed by decreased laryngeal elevation and reduced epiglottis inversion. Swallowing function, VFSS findings, or quantified dysphagia severity showed no significant differences between the groups. In a subgroup analysis of TBI patients, the incidence of tube feeding was higher in patients with surgical intervention than in those without (p=0.011). The swallowing characteristics of dysphagic patients after TBI were comparable to those of dysphagic stroke patients. Common VFSS findings comprised aspiration or penetration, decreased laryngeal elevation, and reduced epiglottis inversion. Patients who underwent surgical intervention after TBI were at high risk of tube feeding requirement.

  11. Effects of Community Exercise Therapy on Metabolic, Brain, Physical, and Cognitive Function Following Stroke: A Randomized Controlled Pilot Trial.

    Science.gov (United States)

    Moore, Sarah A; Hallsworth, Kate; Jakovljevic, Djordje G; Blamire, Andrew M; He, Jiabao; Ford, Gary A; Rochester, Lynn; Trenell, Michael I

    2015-08-01

    Exercise therapy could potentially modify metabolic risk factors and brain physiology alongside improving function post stroke. To explore the short-term metabolic, brain, cognitive, and functional effects of exercise following stroke. A total of 40 participants (>50 years, >6 months post stroke, independently mobile) were recruited to a single-blind, parallel, randomized controlled trial of community-based exercise (19 weeks, 3 times/wk, "exercise" group) or stretching ("control" group). Primary outcome measures were glucose control and cerebral blood flow. Secondary outcome measures were cardiorespiratory fitness, blood pressure, lipid profile, body composition, cerebral tissue atrophy and regional brain metabolism, and physical and cognitive function. Exercise did not change glucose control (homeostasis model assessment 1·5 ± 0·8 to 1·5 ± 0·7 vs 1·6 ± 0·8 to 1·7 ± 0·7, P = .97; CI = -0·5 to 0·49). Medial temporal lobe tissue blood flow increased with exercise (38 ± 8 to 42 ± 10 mL/100 g/min; P function, and cognition also improved with exercise. Exercise therapy improves short-term metabolic, brain, physical, and cognitive function, without changes in glucose control following stroke. The long-term impact of exercise on stroke recurrence, cardiovascular health, and disability should now be explored. © The Author(s) 2014.

  12. Human neural progenitor cell engraftment increases neurogenesis and microglial recruitment in the brain of rats with stroke.

    Directory of Open Access Journals (Sweden)

    Zahra Hassani

    Full Text Available Stem cell transplantation is to date one of the most promising therapies for chronic ischemic stroke. The human conditionally immortalised neural stem cell line, CTX0E03, has demonstrable efficacy in a rodent model of stroke and is currently in clinical trials. Nonetheless, the mechanisms by which it promotes brain repair are not fully characterised. This study investigated the cellular events occurring after CTX0E03 transplantation in the brains of rats that underwent ischemic stroke.We focused on the endogenous proliferative activity of the host brain in response to cell transplantation and determined the identity of the proliferating cells using markers for young neurons (doublecortin, Dcx and microglia (CD11b. So as to determine the chronology of events occurring post-transplantation, we analysed the engrafted brains one week and four weeks post-transplantation.We observed a significantly greater endogenous proliferation in the striatum of ischemic brains receiving a CTX0E03 graft compared to vehicle-treated ischemic brains. A significant proportion of these proliferative cells were found to be Dcx+ striatal neuroblasts. Further, we describe an enhanced immune response after CTX0E03 engraftment, as shown by a significant increase of proliferating CD11b+ microglial cells.Our study demonstrates that few Dcx+ neuroblasts are proliferative in normal conditions, and that this population of proliferative neuroblasts is increased in response to stroke. We further show that CTX0E03 transplantation after stroke leads to the maintenance of this proliferative activity. Interestingly, the preservation of neuronal proliferative activity upon CTX0E03 transplantation is preceded and accompanied by a high rate of proliferating microglia. Our study suggests that microglia might mediate in part the effect of CTX0E03 transplantation on neuronal proliferation in ischemic stroke conditions.

  13. Regulatory T cells are strong promoters of acute ischemic stroke in mice by inducing dysfunction of the cerebral microvasculature.

    Science.gov (United States)

    Kleinschnitz, Christoph; Kraft, Peter; Dreykluft, Angela; Hagedorn, Ina; Göbel, Kerstin; Schuhmann, Michael K; Langhauser, Friederike; Helluy, Xavier; Schwarz, Tobias; Bittner, Stefan; Mayer, Christian T; Brede, Marc; Varallyay, Csanad; Pham, Mirko; Bendszus, Martin; Jakob, Peter; Magnus, Tim; Meuth, Sven G; Iwakura, Yoichiro; Zernecke, Alma; Sparwasser, Tim; Nieswandt, Bernhard; Stoll, Guido; Wiendl, Heinz

    2013-01-24

    We have recently identified T cells as important mediators of ischemic brain damage, but the contribution of the different T-cell subsets is unclear. Forkhead box P3 (FoxP3)-positive regulatory T cells (Tregs) are generally regarded as prototypic anti-inflammatory cells that maintain immune tolerance and counteract tissue damage in a variety of immune-mediated disorders. In the present study, we examined the role of Tregs after experimental brain ischemia/reperfusion injury. Selective depletion of Tregs in the DEREG mouse model dramatically reduced infarct size and improved neurologic function 24 hours after stroke and this protective effect was preserved at later stages of infarct development. The specificity of this detrimental Treg effect was confirmed by adoptive transfer experiments in wild-type mice and in Rag1(-/-) mice lacking lymphocytes. Mechanistically, Tregs induced microvascular dysfunction in vivo by increased interaction with the ischemic brain endothelium via the LFA-1/ICAM-1 pathway and platelets and these findings were confirmed in vitro. Ablation of Tregs reduced microvascular thrombus formation and improved cerebral reperfusion on stroke, as revealed by ultra-high-field magnetic resonance imaging at 17.6 Tesla. In contrast, established immunoregulatory characteristics of Tregs had no functional relevance. We define herein a novel and unexpected role of Tregs in a primary nonimmunologic disease state.

  14. 6-Hydroxydopamine induces brain vascular endothelial inflammation.

    Science.gov (United States)

    Fu, Qizhi; Song, Runluo; Yang, Zhongxi; Shan, Qi; Chen, Wenna

    2017-11-01

    Disruption of the blood-brain barrier associated with endothelial dysfunction is an important hallmark of Parkinson's disease (PD). 6-Hydroxydopamine (6-OHDA) is a synthetic dopamine derivate often used to model PD as it results in retrograde degeneration of striatal dopaminergic (DA) terminals. Presently, the effects of 6-OHDA on endothelial dysfunction remain unknown. Using a 6-OHDA rodent model of PD, we found that administration of 6-OHDA could increase the expression of endothelial adhesion molecules, such as intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and E-selectin. An in vitro study displayed that treatment with 6-OHDA increased the release of these molecules in human brain microvascular endothelial cells in a dose-dependent manner. Correspondingly, 6-OHDA significantly increased attachment of THP-1 monocytes to brain endothelial cells. In addition, real-time polymerase chain reaction and enzyme-linked immunosorbent assay results indicated that 6-OHDA elevated the production of proinflammatory cytokines, such as interleukin-1β, interleukin-6, and tumor necrosis factor-α. Furthermore, 6-OHDA treatment increased the expression of cyclooxygenase-2 and inducible nitric oxide synthase, as well as the production of prostaglandin E2 and nitric oxide. Importantly, 6-OHDA elevated the transcriptional activity of NF-кB by increasing the phosphorylation, degradation, and subsequent nuclear translocation of p65. Mechanistically, the angiotensin II type 1 receptor was found to mediate 6-OHDA-induced endothelial dysfunction. Our findings suggest that 6-OHDA-induced endothelial inflammation may play an important role in the pathogenesis of PD. © 2017 IUBMB Life, 69(11):887-895, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

  15. Tactile Perception for Stroke Induce Changes in Electroencephalography

    Directory of Open Access Journals (Sweden)

    Si-Nae Ahn

    2016-12-01

    Conclusion: The results of this study provided a neurophysiological evidence on tactile perception in individuals with chronic stroke. Occupational therapists should consider an active tactile exploration as a useful modality on occupational performance in rehabilitation training.

  16. FLAIR lesion segmentation: Application in patients with brain tumors and acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Artzi, Moran, E-mail: artzimy@gmail.com [The Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv Sourasky Medical Center, Tel Aviv (Israel); Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv (Israel); Aizenstein, Orna, E-mail: ornaaize@gmail.com [The Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv Sourasky Medical Center, Tel Aviv (Israel); Jonas-Kimchi, Tali, E-mail: talijk@tlvmc.gov.il [Radiology Department, Tel Aviv Sourasky Medical Center, Tel Aviv (Israel); Myers, Vicki, E-mail: vicki_myers@hotmail.com [The Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv Sourasky Medical Center, Tel Aviv (Israel); Hallevi, Hen, E-mail: hen.hallevi@gmail.com [Neurology Department, Tel Aviv Sourasky Medical Center, Tel Aviv (Israel); Ben Bashat, Dafna, E-mail: dafnab@tlvmc.gov.il [The Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv Sourasky Medical Center, Tel Aviv (Israel); Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv (Israel)

    2013-09-15

    Background: Lesion size in fluid attenuation inversion recovery (FLAIR) images is an important clinical parameter for patient assessment and follow-up. Although manual delineation of lesion areas considered as ground truth, it is time-consuming, highly user-dependent and difficult to perform in areas of indistinct borders. In this study, an automatic methodology for FLAIR lesion segmentation is proposed, and its application in patients with brain tumors undergoing therapy; and in patients following stroke is demonstrated. Materials and methods: FLAIR lesion segmentation was performed in 57 magnetic resonance imaging (MRI) data sets obtained from 44 patients: 28 patients with primary brain tumors; 5 patients with recurrent-progressive glioblastoma (rGB) who were scanned longitudinally during anti-angiogenic therapy (18 MRI scans); and 11 patients following ischemic stroke. Results: FLAIR lesion segmentation was obtained in all patients. When compared to manual delineation, a high visual similarity was observed, with an absolute relative volume difference of 16.80% and 20.96% and a volumetric overlap error of 24.87% and 27.50% obtained for two raters: accepted values for automatic methods. Quantitative measurements of the segmented lesion volumes were in line with qualitative radiological assessment in four patients who received anti-anogiogenic drugs. In stroke patients the proposed methodology enabled identification of the ischemic lesion and differentiation from other FLAIR hyperintense areas, such as pre-existing disease. Conclusion: This study proposed a replicable methodology for FLAIR lesion detection and quantification and for discrimination between lesion of interest and pre-existing disease. Results from this study show the wide clinical applications of this methodology in research and clinical practice.

  17. FLAIR lesion segmentation: Application in patients with brain tumors and acute ischemic stroke

    International Nuclear Information System (INIS)

    Artzi, Moran; Aizenstein, Orna; Jonas-Kimchi, Tali; Myers, Vicki; Hallevi, Hen; Ben Bashat, Dafna

    2013-01-01

    Background: Lesion size in fluid attenuation inversion recovery (FLAIR) images is an important clinical parameter for patient assessment and follow-up. Although manual delineation of lesion areas considered as ground truth, it is time-consuming, highly user-dependent and difficult to perform in areas of indistinct borders. In this study, an automatic methodology for FLAIR lesion segmentation is proposed, and its application in patients with brain tumors undergoing therapy; and in patients following stroke is demonstrated. Materials and methods: FLAIR lesion segmentation was performed in 57 magnetic resonance imaging (MRI) data sets obtained from 44 patients: 28 patients with primary brain tumors; 5 patients with recurrent-progressive glioblastoma (rGB) who were scanned longitudinally during anti-angiogenic therapy (18 MRI scans); and 11 patients following ischemic stroke. Results: FLAIR lesion segmentation was obtained in all patients. When compared to manual delineation, a high visual similarity was observed, with an absolute relative volume difference of 16.80% and 20.96% and a volumetric overlap error of 24.87% and 27.50% obtained for two raters: accepted values for automatic methods. Quantitative measurements of the segmented lesion volumes were in line with qualitative radiological assessment in four patients who received anti-anogiogenic drugs. In stroke patients the proposed methodology enabled identification of the ischemic lesion and differentiation from other FLAIR hyperintense areas, such as pre-existing disease. Conclusion: This study proposed a replicable methodology for FLAIR lesion detection and quantification and for discrimination between lesion of interest and pre-existing disease. Results from this study show the wide clinical applications of this methodology in research and clinical practice

  18. Novel humanized recombinant T cell receptor ligands protect the female brain after experimental stroke.

    Science.gov (United States)

    Pan, Jie; Palmateer, Julie; Schallert, Timothy; Hart, Madison; Pandya, Arushi; Vandenbark, Arthur A; Offner, Halina; Hurn, Patricia D

    2014-10-01

    Transmigration of peripheral leukocytes to the brain is a major contributor to cerebral ischemic cell death mechanisms. Humanized partial major histocompatibility complex class II constructs (pMHC), covalently linked to myelin peptides, are effective for treating experimental stroke in males, but new evidence suggests that some inflammatory cell death mechanisms after brain injury are sex-specific. We here demonstrate that treatment with pMHC constructs also improves outcomes in female mice with middle cerebral artery occlusion (MCAO). HLA-DR2 transgenic female mice with MCAO were treated with RTL1000 (HLA-DR2 moiety linked to human MOG-35-55 peptide), HLA-DRa1-MOG-35-55, or vehicle (VEH) at 3, 24, 48, and 72 h after reperfusion and were recovered for 96 h or 2 weeks post-injury for measurement of histology (TTC staining) or behavioral testing. RTL1000- and DRa1-MOG-treated mice had profoundly reduced infarct volumes as compared to the VEH group, although higher doses of DRa1-MOG were needed for females vs. males evaluated previously. RTL1000-treated females also exhibited strongly improved functional recovery in a standard cylinder test. In novel studies of post-ischemic ultrasonic vocalization (USV), as measured by animal calls to their cage mates, we modeled in mice the post-stroke speech deficits common in human stroke survivors. The number of calls was reduced in injured animals relative to pre-MCAO baseline regardless of RTL1000 treatment status. However, call duration was significantly improved by RTL1000 treatment, suggesting benefit to the animal's recovery of vocalization capability. We conclude that both the parent RTL1000 molecule and the novel non-polymorphic DRα1-MOG-35-55 construct were highly effective immunotherapies for treatment of transient cerebral ischemia in females.

  19. Effects of virtual reality-based bilateral upper-extremity training on brain activity in post-stroke patients.

    Science.gov (United States)

    Lee, Su-Hyun; Kim, Yu-Mi; Lee, Byoung-Hee

    2015-07-01

    [Purpose] This study investigated the therapeutic effects of virtual reality-based bilateral upper-extremity training on brain activity in patients with stroke. [Subjects and Methods] Eighteen chronic stroke patients were divided into two groups: the virtual reality-based bilateral upper-extremity training group (n = 10) and the bilateral upper-limb training group (n = 8). The virtual reality-based bilateral upper-extremity training group performed bilateral upper-extremity exercises in a virtual reality environment, while the bilateral upper-limb training group performed only bilateral upper-extremity exercise. All training was conducted 30 minutes per day, three times per week for six weeks, followed by brain activity evaluation. [Results] Electroencephalography showed significant increases in concentration in the frontopolar 2 and frontal 4 areas, and significant increases in brain activity in the frontopolar 1 and frontal 3 areas in the virtual reality-based bilateral upper-extremity training group. [Conclusion] Virtual reality-based bilateral upper-extremity training can improve the brain activity of stroke patients. Thus, virtual reality-based bilateral upper-extremity training is feasible and beneficial for improving brain activation in stroke patients.

  20. Hibernation-like state induced by an opioid peptide protects against experimental stroke

    Directory of Open Access Journals (Sweden)

    Su Tsung-Ping

    2009-06-01

    Full Text Available Abstract Background Delta opioid peptide [D-ala2,D-leU5]enkephalin (DADLE induces hibernation in summer ground squirrels, and enhances preservation and survival of isolated or transplanted lungs and hearts. In the present study, we investigated the protective effect of DADLE in the central nervous system. Results Adult Sprague-Dawley rats were pretreated with DADLE (4 mg/kg every 2 h × 4 injections, i.p. or saline prior to unilateral occlusion of the middle cerebral artery (MCA. Daily behavioral tests revealed that ischemic animals treated with DADLE did not show any significant behavioral dysfunctions compared with saline-treated ischemic animals. Opioid antagonists only transiently inhibited the protective effect of DADLE, indicating the participation of non-opioid mechanisms in DADLE neuroprotection. Histological examination using triphenyltetrazolium chloride (TTC revealed that brains from ischemic animals treated with DADLE, either alone or with adjuvant opioid blockers, exhibited almost completely intact striata. In contrast, brains from ischemic animals that received saline showed significant infarction in the lateral striatum. Analyses of apoptotic cell death revealed a significant increase in the p-53 mRNA expression in the striatum of ischemic animals that received saline, while those that received DADLE exhibited near normal striatal p-53 expression. This protective effect was accompanied by significant increments in protein levels of glial cell line-derived neurotrophic factor in the striatum of DADLE-treated ischemic animals. Conclusion These results indicate that DADLE protected against necrotic and apoptotic cell death processes associated with ischemia-reperfusion injury. The present study demonstrates that delta opioids are crucially involved in stroke, suggesting that the opioid system is important in the study of brain injury and protection.

  1. Quick Brain Magnetic Resonance Imaging With Diffusion-Weighted Imaging as a First Imaging Modality in Pediatric Stroke.

    Science.gov (United States)

    Christy, Alison; Murchison, Charles; Wilson, Jenny L

    2018-01-01

    Diagnostic delay hinders management of pediatric arterial ischemic stroke. Quick brain MRI with diffusion-weighted imaging sequences may provide a rapid diagnosis without the ionizing radiation of a computed tomography (CT) scan. This was a single center retrospective chart review of children one month to 18 years old with acute arterial ischemic stroke hospitalized between January 2010 and January 2017. We evaluated sensitivity and the time to diagnostic study based on the first imaging study (CT or quick brain MRI with diffusion-weighted imaging). Twenty-five patients were included. Eleven patients (44%) were initially assessed with CT, 10 (40%) with quick brain MRI with diffusion-weighted imaging, and four (16%) with a full MRI. Compared with children undergoing CT, children with quick brain MRI with diffusion-weighted imaging as first study were younger (5.8 versus 14.1 years, P hospitalized at stroke onset (70% versus 18.2%, P = 0.03). Quick brain MRI with diffusion-weighted imaging was more sensitive for ischemia than CT (100% versus 27.3%). The median time from presentation to diagnostic imaging was 4.3 hours, with no differences between CT and quick brain MRI with diffusion-weighted imaging groups, although the quick brain MRI with diffusion-weighted imaging group had a shorter median time from first imaging to diagnostic imaging (P = 0.002). There were no significant missed findings on quick brain MRI with diffusion-weighted imaging. Quick brain MRI with diffusion-weighted imaging was more sensitive than CT for detecting ischemia and may be considered as the first study for some children presenting with suspected arterial ischemic stroke. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Shortened constraint-induced movement therapy in subacute stroke - no effect of using a restraint

    DEFF Research Database (Denmark)

    Brogårdh, Christina; Vestling, Monika; Sjölund, Bengt H

    2009-01-01

    OBJECTIVE: To examine the effect of using a mitt during shortened constraint-induced movement therapy for patients in the subacute phase after stroke. SUBJECTS: Twenty-four patients with stroke (mean age 57.6 (standard deviation (SD) 8.5) years; average 7 weeks post-stroke) with mild to moderate......, no statistically significant differences between the groups were found in any measures at any point in time. CONCLUSION: In this study, no effect of using a restraint in patients with subacute stroke was found. Thus, this component in the constraint-induced therapy concept seems to be of minor importance...... Scale, the Sollerman hand function test, the 2-Point Discrimination test and Motor Activity Log test. RESULTS: Patients in both groups showed significant improvements in arm and hand motor performance and on self-reported motor ability after 2 weeks of therapy and at 3 months follow-up. However...

  3. A Generative Probabilistic Model and Discriminative Extensions for Brain Lesion Segmentation - With Application to Tumor and Stroke

    DEFF Research Database (Denmark)

    Menze, Bjoern H.; Van Leemput, Koen; Lashkari, Danial

    2016-01-01

    We introduce a generative probabilistic model for segmentation of brain lesions in multi-dimensional images that generalizes the EM segmenter, a common approach for modelling brain images using Gaussian mixtures and a probabilistic tissue atlas that employs expectation-maximization (EM...... jointly from the image data. It delineates lesion areas individually in each channel, allowing for differences in lesion appearance across modalities, an important feature of many brain tumor imaging sequences. We also propose discriminative model extensions to map the output of the generative model...... patient scans, and multimodal brain images of patients with acute and subacute ischemic stroke. We find the generative model that has been designed for tumor lesions to generalize well to stroke images, and the extended discriminative-discriminative model to be one of the top ranking methods in the BRATS...

  4. Blood flow and vascular reactivity in collaterally perfused brain tissue. Evidence of an ischemic penumbra in patients with acute stroke

    DEFF Research Database (Denmark)

    Olsen, T S; Larsen, B; Herning, M

    1983-01-01

    In a group of 48 patients with completed stroke, 8 patients had viable collaterally perfused brain tissue which was accessible for rCBF recordings with a two dimensional technique. All 8 had deep subcortical infarcts on CT-scan, and angiographic occlusion of the arteries normally supplying...... the infarcted territory. The brain tissue overlying the deep infarcts appeared normal on CT-scan and was supplied by collateral circulation. rCBF was measured in all within 72 hours after the stroke. The intra-carotid Xe-133 injection method and a 254 multidetector camera were used to study rCBF. Relatively...... ischemic low flow areas were a constant finding in the collaterally perfused tissue. In 6 of the patients, the collaterally perfused part of the brain had low flow values comparable to those of an "ischemic penumbra" (viable, but functionally depressed brain tissue due to inadequate perfusion...

  5. Defining Optimal Brain Health in Adults: A Presidential Advisory From the American Heart Association/American Stroke Association.

    Science.gov (United States)

    Gorelick, Philip B; Furie, Karen L; Iadecola, Costantino; Smith, Eric E; Waddy, Salina P; Lloyd-Jones, Donald M; Bae, Hee-Joon; Bauman, Mary Ann; Dichgans, Martin; Duncan, Pamela W; Girgus, Meighan; Howard, Virginia J; Lazar, Ronald M; Seshadri, Sudha; Testai, Fernando D; van Gaal, Stephen; Yaffe, Kristine; Wasiak, Hank; Zerna, Charlotte

    2017-10-01

    Cognitive function is an important component of aging and predicts quality of life, functional independence, and risk of institutionalization. Advances in our understanding of the role of cardiovascular risks have shown them to be closely associated with cognitive impairment and dementia. Because many cardiovascular risks are modifiable, it may be possible to maintain brain health and to prevent dementia in later life. The purpose of this American Heart Association (AHA)/American Stroke Association presidential advisory is to provide an initial definition of optimal brain health in adults and guidance on how to maintain brain health. We identify metrics to define optimal brain health in adults based on inclusion of factors that could be measured, monitored, and modified. From these practical considerations, we identified 7 metrics to define optimal brain health in adults that originated from AHA's Life's Simple 7: 4 ideal health behaviors (nonsmoking, physical activity at goal levels, healthy diet consistent with current guideline levels, and body mass index brain health but recognize that the truly ideal circumstance may be uncommon because there is a continuum of brain health as demonstrated by AHA's Life's Simple 7. Therefore, there is opportunity to improve brain health through primordial prevention and other interventions. Furthermore, although cardiovascular risks align well with brain health, we acknowledge that other factors differing from those related to cardiovascular health may drive cognitive health. Defining optimal brain health in adults and its maintenance is consistent with the AHA's Strategic Impact Goal to improve cardiovascular health of all Americans by 20% and to reduce deaths resulting from cardiovascular disease and stroke by 20% by the year 2020. This work in defining optimal brain health in adults serves to provide the AHA/American Stroke Association with a foundation for a new strategic direction going forward in cardiovascular health

  6. Tooth Loss Is Associated with Brain White Matter Change and Silent Infarction among Adults without Dementia and Stroke

    Science.gov (United States)

    Minn, Yang-Ki; Park, Hyunyoung; Cheong, Jin-Sung; Yang, Hyunduk; Lee, Sungik; Do, Seung-Yeon; Kang, Ji-Sook

    2013-01-01

    Periodontal disease is a predictor of stroke and cognitive impairment. The association between the number of lost teeth (an indicator of periodontal disease) and silent infarcts and cerebral white matter changes on brain CT was investigated in community-dwelling adults without dementia or stroke. Dental examination and CT were performed in 438 stroke- and dementia-free subjects older than 50 yr (mean age, 63 ± 7.9 yr), who were recruited for an early health check-up program as part of the Prevention of Stroke and Dementia (PRESENT) project between 2009 and 2010. In unadjusted analyses, the odds ratio (OR) for silent cerebral infarcts and cerebral white matter changes for subjects with 6-10 and > 10 lost teeth was 2.3 (95% CI, 1.38-4.39; P = 0.006) and 4.2 (95% CI, 1.57-5.64; P dementia-free adults. PMID:23772160

  7. New approach to detect and classify stroke in skull CT images via analysis of brain tissue densities.

    Science.gov (United States)

    Rebouças Filho, Pedro P; Sarmento, Róger Moura; Holanda, Gabriel Bandeira; de Alencar Lima, Daniel

    2017-09-01

    Cerebral vascular accident (CVA), also known as stroke, is an important health problem worldwide and it affects 16 million people worldwide every year. About 30% of those that have a stroke die and 40% remain with serious physical limitations. However, recovery in the damaged region is possible if treatment is performed immediately. In the case of a stroke, Computed Tomography (CT) is the most appropriate technique to confirm the occurrence and to investigate its extent and severity. Stroke is an emergency problem for which early identification and measures are difficult; however, computer-aided diagnoses (CAD) can play an important role in obtaining information imperceptible to the human eye. Thus, this work proposes a new method for extracting features based on radiological density patterns of the brain, called Analysis of Brain Tissue Density (ABTD). The proposed method is a specific approach applied to CT images to identify and classify the occurrence of stroke diseases. The evaluation of the results of the ABTD extractor proposed in this paper were compared with extractors already established in the literature, such as features from Gray-Level Co-Occurrence Matrix (GLCM), Local binary patterns (LBP), Central Moments (CM), Statistical Moments (SM), Hu's Moment (HM) and Zernike's Moments (ZM). Using a database of 420 CT images of the skull, each extractor was applied with the classifiers such as MLP, SVM, kNN, OPF and Bayesian to classify if a CT image represented a healthy brain or one with an ischemic or hemorrhagic stroke. ABTD had the shortest extraction time and the highest average accuracy (99.30%) when combined with OPF using the Euclidean distance. Also, the average accuracy values for all classifiers were higher than 95%. The relevance of the results demonstrated that the ABTD method is a useful algorithm to extract features that can potentially be integrated with CAD systems to assist in stroke diagnosis. Copyright © 2017 Elsevier B.V. All rights

  8. The influence of meteorological and geomagnetic factors on acute myocardial infarction and brain stroke in Moscow, Russia

    Science.gov (United States)

    Shaposhnikov, Dmitry; Revich, Boris; Gurfinkel, Yuri; Naumova, Elena

    2014-07-01

    Evidence of the impact of air temperature and pressure on cardiovascular morbidity is still quite limited and controversial, and even less is known about the potential influence of geomagnetic activity. The objective of this study was to assess impacts of air temperature, barometric pressure and geomagnetic activity on hospitalizations with myocardial infarctions and brain strokes. We studied 2,833 myocardial infarctions and 1,096 brain strokes registered in two Moscow hospitals between 1992 and 2005. Daily event rates were linked with meteorological and geomagnetic conditions, using generalized linear model with controls for day of the week, seasonal and long-term trends. The number of myocardial infarctions decreased with temperature, displayed a U-shaped relationship with pressure and variations in pressure, and increased with geomagnetic activity. The number of strokes increased with temperature, daily temperature range and geomagnetic activity. Detrimental effects on strokes of low pressure and falling pressure were observed. Relative risks of infarctions and strokes during geomagnetic storms were 1.29 (95 % CI 1.19-1.40) and 1.25 (1.10-1.42), respectively. The number of strokes doubled during cold spells. The influence of barometric pressure on hospitalizations was relatively greater than the influence of geomagnetic activity, and the influence of temperature was greater than the influence of pressure. Brain strokes were more sensitive to inclement weather than myocardial infarctions. This paper provides quantitative estimates of the expected increases in hospital admissions on the worst days and can help to develop preventive health plans for cardiovascular diseases.

  9. Associations of Circulating Growth Differentiation Factor-15 and ST2 Concentrations With Subclinical Vascular Brain Injury and Incident Stroke

    DEFF Research Database (Denmark)

    Andersson, Charlotte; Preis, Sarah R; Beiser, Alexa

    2015-01-01

    BACKGROUND AND PURPOSE: Growth differentiation factor-15 (GDF-15) and soluble (s)ST2 are markers of cardiac and vascular stress. We investigated the associations between circulating concentrations of these biomarkers and incident stroke and subclinical vascular brain injury in a sample from the F...

  10. Succinate-induced neuronal mitochondrial fission and hexokinase II malfunction in ischemic stroke: Therapeutical effects of kaempferol.

    Science.gov (United States)

    Wu, Bin; Luo, Hong; Zhou, Xu; Cheng, Cai-Yi; Lin, Lin; Liu, Bao-Lin; Liu, Kang; Li, Ping; Yang, Hua

    2017-09-01

    Mitochondrial dysfunction is known as one of causative factors in ischemic stroke, leading to neuronal cell death. The present work was undertaken to investigate whether succinate induces neuron apoptosis by regulating mitochondrial morphology and function. In neurons, oxygen-glucose deprivation induced succinate accumulation due to the reversal of succinate dehydrogenase (SDH) activation, leading to mitochondrial fission. Kaempferol inhibited mitochondrial fission and maintained mitochondrial HK-II through activation of Akt, and thereby protected neurons from succinate-mediated ischemi injury. Knockdown of Akt2 with siRNA diminished the effect of kaempferol, indicating that kaempferol suppressed dynamin-related protein 1 (Drp1) activation and promoted HK-II mitochondrial binding dependently on Akt. Moreover, we demonstrated that kaempferol potentiated autophagy during oxygen and glucose deprivation, contributing to protecting neuron survival against succinate insult. In vivo, oral administration of kaempferol in mice attenuated the infract volume after ischemic and reperfusion (I/R) injury and reproduced the similar mitochondrial protective effect in the brain infract area. This study indicates that succinate accumulation plays a pivotal role in I/R injury-induced neuronal mitochondrial dysfunction, and suggests that modulation of Drp1 phosphorylation might be potential therapeutic strategy to protect neuron mitochondrial integrity and treat ischemic stroke. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Cognitive and Neurophysiological Effects of Non-invasive Brain Stimulation in Stroke Patients after Motor Rehabilitation.

    Science.gov (United States)

    D'Agata, Federico; Peila, Elena; Cicerale, Alessandro; Caglio, Marcella M; Caroppo, Paola; Vighetti, Sergio; Piedimonte, Alessandro; Minuto, Alice; Campagnoli, Marcello; Salatino, Adriana; Molo, Maria T; Mortara, Paolo; Pinessi, Lorenzo; Massazza, Giuseppe

    2016-01-01

    The primary aim of this study was to evaluate and compare the effectiveness of two specific Non-Invasive Brain Stimulation (NIBS) paradigms, the repetitive Transcranial Magnetic Stimulation (rTMS), and transcranial Direct Current Stimulation (tDCS), in the upper limb rehabilitation of patients with stroke. Short and long term outcomes (after 3 and 6 months, respectively) were evaluated. We measured, at multiple time points, the manual dexterity using a validated clinical scale (ARAT), electroencephalography auditory event related potentials, and neuropsychological performances in patients with chronic stroke of middle severity. Thirty four patients were enrolled and randomized. The intervention group was treated with a NIBS protocol longer than usual, applying a second cycle of stimulation, after a washout period, using different techniques in the two cycles (rTMS/tDCS). We compared the results with a control group treated with sham stimulation. We split the data analysis into three studies. In this first study we examined if a cumulative effect was clinically visible. In the second study we compared the effects of the two techniques. In the third study we explored if patients with minor cognitive impairment have most benefit from the treatment and if cognitive and motor outcomes were correlated. We found that the impairment in some cognitive domains cannot be considered an exclusion criterion for rehabilitation with NIBS. ERP improved, related to cognitive and attentional processes after stimulation on the motor cortex, but transitorily. This effect could be linked to the restoration of hemispheric balance or by the effects of distant connections. In our study the effects of the two NIBS were comparable, with some advantages using tDCS vs. rTMS in stroke rehabilitation. Finally we found that more than one cycle (2-4 weeks), spaced out by washout periods, should be used, only in responder patients, to obtain clinical relevant results.

  12. Shoulder Subluxation and Shoulder-Hand Syndrome After Stroke; Effect of Brain Lesion Location And Side

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    Levent Ediz

    2011-09-01

    Full Text Available Aim: The effect of brain lesion location and involved brain side in the development of shoulder subluxation (SS and shoulder hand syndrome (SHS is still unclear. The aim of the current study was to evaluate the relationships of SS and SHS with brain lesion location and stroke side. Material and Methods: The inpatient files of the hemiplegic patients, who were hospitalized for rehabilitation, were evaluated resrospectively. Brain lesion location and involved hemisphere side were assessed by brain CT at the insult time. Brain lesion location groups were comprised as following 4 groups which included 35 patients in each group. Group I: Small superficial infarct. This type infarcts involve small area infarct (no more than 20 mm in diameter on a cerebral lobe, such as a small right or left frontal lobe infarct. Group II: Large superficial infarct. Infarcts more than 20 mm in diameter on a cerebral lobe or two or more lobes of one cerebral hemisphere, such as a frontoparietal infarct in the left cerebral hemisphere or frontotemporo- parietal infarct in right or left cerebral hemisphere. Group III: Deep  nfarct. Infarcts of the internal capsule, basal ganglia or thalamus. Group IV:  ombination of deep and large superficial infarcts (combined group II+III. Internal capsule or basal ganglia or thalamic infarct combined with fronto-temporal or fronto-parietal or emporoparieto-occipital infarct on one cerebral hemisphere. A total of 140 hemiplegic patients then devided into 2 groups according to the development of SS and/or SHS.Results: A significant correlation was found between brain lesion locations and SS and/or SHS development. The groups with combined deep and large superficial, and large superficial infarcts showed more frequent SS and/or SHS development. Patients with SS and/or SHS had got low stages at baseline in the upper extremity according to upper extremity Brunnstroma level, upper extremity Ashworth stage and low stages of functional

  13. Pretreatment with Shuanghe-Tang Extract Attenuates Postischemic Brain Injury and Edema in a Mouse Model of Stroke: An Analysis of Medicinal Herbs Listed in Dongui Bogam

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    Min Jae Kim

    2018-01-01

    Full Text Available Aim. Although stroke is among the leading causes of death and long-term disability, there are few effective treatments for limiting the severity of neurological sequelae. We evaluated the effects of 29 medicinal herbs listed in the Pung chapter of the 17th century Korean medical text Dongui Bogam on stroke symptoms in a mouse model of cerebral ischemia. Methods. Focal cerebral ischemia was induced via photothrombosis. Infarct volume, brain edema, and neurological deficits were evaluated. Immunofluorescence staining for tight junction proteins and aquaporin 4 (AQP4 was performed following ischemic injury. Results. Based on our initial findings, we examined the effects of two prescriptions in which the candidate herbs comprised more than 60% of the total formula: Shuanghe-tang and Zengsunsiwu-tang. Pretreatment with Shuanghe-tang significantly reduced infarct volume, decreased blood-brain barrier (BBB breakdown, attenuated edema, and improved neurological and motor functions in a dose-dependent manner (30, 100, and 300 mg/kg, while no such effects were observed in mice pretreated with Zengsunsiwu-tang. Immunohistochemical analysis revealed significant increases in ipsilateral occludin and zonula occludens 1 (ZO-1 expression in Shuanghe-tang-pretreated mice, as well as increased AQP4 immunofluorescence. Conclusions. These results indicate that Shuanghe-tang may protect against brain injury and promote recovery of neurological function following ischemia.

  14. The Neuroprotective Effects of Flaxseed Oil Supplementation on Functional Motor Recovery in a Model of Ischemic Brain Stroke: Upregulation of BDNF and GDNF.

    Science.gov (United States)

    Bagheri, Abolqasem; Talei, Sahand; Hassanzadeh, Negar; Mokhtari, Tahmineh; Akbari, Mohammad; Malek, Fatemeh; Jameie, Seyed Behnamedin; Sadeghi, Yousef; Hassanzadeh, Gholamreza

    2017-12-01

    Cerebral ischemic stroke is a common leading cause of disability. Flaxseed is a richest plant-based source of antioxidants. In this study, the effects of flaxseed oil (FSO) pretreatment on functional motor recovery and gene expression and protein content of neurotrophic factors in motor cortex area in rat model of brain ischemia/reperfusion (I/R) were assessed. Transient middle cerebral artery occlusion (tMCAo) in rats was used as model brain I/R. Rats (6 in each group) were randomly divided into four groups of Control (Co+normal saline [NS]), Sham (Sh+NS), tMCAo+NS and tMCAo+FSO. After three weeks of pretreatment with vehicle or FSO (0.2 ml~800 mg/kg body weight), the rats were operated in sham and ischemic groups. Ischemia was induced for 1 h and then reperfused. After 24 h of reperfusion, neurological examination was performed, and animals were sacrificed, and their brains were used for molecular and histopathological studies. FSO significantly improved the functional motor recovery compared with tMCAo+NS group (Pmotor cortex area following cerebral ischemic stroke by increasing the neurotrophic factors (BDNF, GDNF).

  15. Therapeutic Potential of Umbilical Cord Blood Stem Cells on Brain Damage of a Model of Stroke

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Nikravesh

    2011-11-01

    Full Text Available Introduction: Human cord blood-derived stem cells are a rich source of stem cells as well as precursors. With regard to the researchers have focused on the therapeutic potential of stem cell in the neurological disease such as stroke, the aim of this study was the investiga-tion of the therapeutic effects of human cord blood-derived stem cells in cerebral ischemia on rat. Methods: This study was carried out on young rats. Firstly, to create a laboratory model of ischemic stroke, carotid artery of animals was occluded for 30 minutes. Then, umbilical cord blood cells were isolated and labeled using bromodeoxyuridine and 2×105 cells were injected into the experimental group via the tail vein. Rats with hypoxic condi-tions were used as a sham group. A group of animals did not receive any injection or sur-geries were used as a control. Results: Obtained results were evaluated based on behavior-al responses and immunohistochemistry, with emphasis on areas of putamen and caudate nucleus in the control, sham and experimental groups. Our results indicated that behavioral recovery was observed in the experimental group compared to the either the sham or the control group. However, histological studies demonstrated a low percent of tissue injury in the experimental group in comparison with the sham group. Conclusion: Stem cell trans-plantation is beneficial for the brain tissue reparation after hypoxic ischemic cell death.

  16. Stroke prognosis by applying double thresholds on CT-perfusion-brain images

    Science.gov (United States)

    Chokchaitam, Somchart; Santipromwong, Nittaya; Muengtaweepongsa, Sombat

    2013-03-01

    The CT-perfusion image shows information of brain abnormalities such as its size and location. Generally, neurologist diagnoses stroke disease using CT-perfusion images such as Cerebral blood flow (CBF), cerebral blood volume (CBV). In our previous report, we applied threshold technique to divide amount of CBV and CBF into low and high level. Then, their levels are applied to identify normal tissue areas, dead tissue areas (infract core) and blood-cot tissue areas (infract penumbra). However, it's not totally correct, if the same threshold is applied to the whole area (it must depend on size of blood vessel in that area. In this report, we propose double thresholds to divided CBV and CBF into 3 levels: very low, medium and very high levels. Very low and very high levels are definitely implied to bad areas and good areas, respectively. The proposed double thresholds makes stroke prognosis more accurate. The simulation results confirm that our proposed results closed to results defined from neurologist comparing to the conventional results.

  17. Using non-invasive brain stimulation to augment motor training-induced plasticity

    Directory of Open Access Journals (Sweden)

    Pascual-Leone Alvaro

    2009-03-01

    Full Text Available Abstract Therapies for motor recovery after stroke or traumatic brain injury are still not satisfactory. To date the best approach seems to be the intensive physical therapy. However the results are limited and functional gains are often minimal. The goal of motor training is to minimize functional disability and optimize functional motor recovery. This is thought to be achieved by modulation of plastic changes in the brain. Therefore, adjunct interventions that can augment the response of the motor system to the behavioural training might be useful to enhance the therapy-induced recovery in neurological populations. In this context, noninvasive brain stimulation appears to be an interesting option as an add-on intervention to standard physical therapies. Two non-invasive methods of inducing electrical currents into the brain have proved to be promising for inducing long-lasting plastic changes in motor systems: transcranial magnetic stimulation (TMS and transcranial direct current stimulation (tDCS. These techniques represent powerful methods for priming cortical excitability for a subsequent motor task, demand, or stimulation. Thus, their mutual use can optimize the plastic changes induced by motor practice, leading to more remarkable and outlasting clinical gains in rehabilitation. In this review we discuss how these techniques can enhance the effects of a behavioural intervention and the clinical evidence to date.

  18. Neural network remodeling underlying motor map reorganization induced by rehabilitative training after ischemic stroke.

    Science.gov (United States)

    Okabe, Naohiko; Shiromoto, Takashi; Himi, Naoyuki; Lu, Feng; Maruyama-Nakamura, Emi; Narita, Kazuhiko; Iwachidou, Nobuhisa; Yagita, Yoshiki; Miyamoto, Osamu

    2016-12-17

    Motor map reorganization is believed to be one mechanism underlying rehabilitation-induced functional recovery. Although the ipsilesional secondary motor area has been known to reorganize motor maps and contribute to rehabilitation-induced functional recovery, it is unknown how the secondary motor area is reorganized by rehabilitative training. In the present study, using skilled forelimb reaching tasks, we investigated neural network remodeling in the rat rostral forelimb area (RFA) of the secondary motor area during 4weeks of rehabilitative training. Following photothrombotic stroke in the caudal forelimb area (CFA), rehabilitative training led to task-specific recovery and motor map reorganization in the RFA. A second injury to the RFA resulted in reappearance of motor deficits. Further, when both the CFA and RFA were destroyed simultaneously, rehabilitative training no longer improved task-specific recovery. In neural tracer studies, although rehabilitative training did not alter neural projection to the RFA from other brain areas, rehabilitative training increased neural projection from the RFA to the lower spinal cord, which innervates the muscles in the forelimb. Double retrograde tracer studies revealed that rehabilitative training increased the neurons projecting from the RFA to both the upper cervical cord, which innervates the muscles in the neck, trunk, and part of the proximal forelimb, and the lower cervical cord. These results suggest that neurons projecting to the upper cervical cord provide new connections to the denervated forelimb area of the spinal cord, and these new connections may contribute to rehabilitation-induced task-specific recovery and motor map reorganization in the secondary motor area. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. Multiplex Brain Proteomic Analysis Revealed the Molecular Therapeutic Effects of Buyang Huanwu Decoction on Cerebral Ischemic Stroke Mice.

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    Hong-Jhang Chen

    Full Text Available Stroke is the second-leading cause of death worldwide, and tissue plasminogen activator (TPA is the only drug used for a limited group of stroke patients in the acute phase. Buyang Huanwu Decoction (BHD, a traditional Chinese medicine prescription, has long been used for improving neurological functional recovery in stroke. In this study, we characterized the therapeutic effect of TPA and BHD in a cerebral ischemia/reperfusion (CIR injury mouse model using multiplex proteomics approach. After the iTRAQ-based proteomics analysis, 1310 proteins were identified from the mouse brain with <1% false discovery rate. Among them, 877 quantitative proteins, 10.26% (90/877, 1.71% (15/877, and 2.62% (23/877 of the proteins was significantly changed in the CIR, BHD treatment, and TPA treatment, respectively. Functional categorization analysis showed that BHD treatment preserved the integrity of the blood-brain barrier (BBB (Alb, Fga, and Trf, suppressed excitotoxicity (Grm5, Gnai, and Gdi, and enhanced energy metabolism (Bdh, thereby revealing its multiple effects on ischemic stroke mice. Moreover, the neurogenesis marker doublecortin was upregulated, and the activity of glycogen synthase kinase 3 (GSK-3 and Tau was inhibited, which represented the neuroprotective effects. However, TPA treatment deteriorated BBB breakdown. This study highlights the potential of BHD in clinical applications for ischemic stroke.

  20. In vivo bioimpedance measurement of healthy and ischaemic rat brain: implications for stroke imaging using electrical impedance tomography

    International Nuclear Information System (INIS)

    Dowrick, T; Blochet, C; Holder, D

    2015-01-01

    In order to facilitate the imaging of haemorrhagic and ischaemic stroke using frequency difference electrical impedance tomography (EIT), impedance measurements of normal and ischaemic brain, and clotted blood during haemorrhage, were gathered using a four-terminal technique in an in vivo animal model, a first for ischaemic measurements. Differences of 5–10% in impedance were seen between the frequency spectrums of healthy and ischaemic brain, over the frequency range 0–3 kHz, while the spectrum of blood was predominately uniform. The implications of imaging blood/ischaemia in the brain using electrical impedance tomography are discussed, supporting the notion that it will be possible to differentiate stroke from haemorrhage. (paper)

  1. In vivo bioimpedance measurement of healthy and ischaemic rat brain: implications for stroke imaging using electrical impedance tomography.

    Science.gov (United States)

    Dowrick, T; Blochet, C; Holder, D

    2015-06-01

    In order to facilitate the imaging of haemorrhagic and ischaemic stroke using frequency difference electrical impedance tomography (EIT), impedance measurements of normal and ischaemic brain, and clotted blood during haemorrhage, were gathered using a four-terminal technique in an in vivo animal model, a first for ischaemic measurements. Differences of 5-10% in impedance were seen between the frequency spectrums of healthy and ischaemic brain, over the frequency range 0-3 kHz, while the spectrum of blood was predominately uniform. The implications of imaging blood/ischaemia in the brain using electrical impedance tomography are discussed, supporting the notion that it will be possible to differentiate stroke from haemorrhage.

  2. Borneol Attenuates Ultrasound-Targeted Microbubble Destruction-Induced Blood–Brain Barrier Opening in Focal Cerebral Ischemia

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    Xiao-guang Zhang

    2017-12-01

    Full Text Available Ultrasound-targeted microbubble destruction (UTMD and the herb medicine borneol can both facilitate the delivery of therapeutic agents to diseased brain regions and serve as promising adjuvant neuroprotective therapies. Our preliminary experiments showed that UTMD could exacerbate ischemic blood–brain barrier (BBB opening, while borneol can protect the BBB. In this study, we tested the hypothesis that the combination of UTMD and borneol could attenuate UTMD-induced injury to the BBB under ischemic stroke conditions. Male albino mice were subjected to 60-min middle cerebral artery occlusion (MCAO with reperfusion. Borneol and UTMD was given to mice 3 days before and 24 h after MCAO induction. BBB permeability, brain water contents, ultrastructural changes of the BBB and histopathological alterations were evaluated. Our data demonstrated that UTMD aggravated the leakage of Evans blue dye, ultrastructural alterations of cerebral microvasculature, brain edema, and even induced cerebral hemorrhage in ischemic stroke mice. Pretreatment with borneol significantly attenuated the above detrimental effects of UTMD on the BBB. This study indicates that under ischemic stroke conditions, the BBB becomes vulnerable to UTMD intervention, and the combination of borneol can help to maintain the integrity of the BBB.

  3. Association between neuroserpin and molecular markers of brain damage in patients with acute ischemic stroke.

    Science.gov (United States)

    Rodríguez-González, Raquel; Sobrino, Tomás; Rodríguez-Yáñez, Manuel; Millán, Mónica; Brea, David; Miranda, Elena; Moldes, Octavio; Pérez, Juan; Lomas, David A; Leira, Rogelio; Dávalos, Antoni; Castillo, José

    2011-05-11

    Neuroserpin has shown neuroprotective effects in animal models of cerebral ischemia and has been associated with functional outcome after ischemic stroke. Our aim was to study whether neuroserpin serum levels could be associated to biomarkers of excitotoxicity, inflammation and blood brain barrier disruption. We prospectively included 129 patients with ischemic stroke (58.1% male; mean age, 72.4 ± 9.6 years) not treated with tPA within 12 hours (h) of symptoms onset (mean time, 4.7 ± 2.1 h). Poor functional outcome at 3 months was considered as a modified Rankin scale score >2. Serum levels of neuroserpin, Interleukin 6 (IL-6), Intercellular adhesion molecule-1 (ICAM-1), active Matrix metalloproteinase 9 (MMP-9), and cellular fibronectin (cFn) (determined by ELISA) and glutamate (determined by HPLC) were measured on admission, 24 and 72 h. The main variable was considered the decrease of neuroserpin levels within the first 24 h. ROC analysis was used to select the best predictive value for neuroserpin to predict poor functional outcome due to a lack of linearity. The decrease of neuroserpin levels within the first 24 h was negatively correlated with serum levels at 24 hours of glutamate (r = -0.642), IL-6 (r = -0.678), ICAM-1 (r = -0.345), MMP-9 (r = -0.554) and cFn (r = -0.703) (all P < 0.0001). In the multivariate analysis, serum levels of glutamate (OR, 1.04; CI95%, 1.01-1.06, p = 0.001); IL-6 (OR, 1.4; CI95%, 1.1-1.7, p = 0.001); and cFn (OR, 1.3; CI95%, 1.1-1.6, p = 0.002) were independently associated with a decrease of neuroserpin levels <70 ng/mL at 24 h after adjusting for confounding factors. These findings suggest that neuroprotective properties of neuroserpin may be related to the inhibition of excitotoxicity, inflammation, as well as blood brain barrier disruption that occur after acute ischemic stroke.

  4. Constraint-induced movement therapy for the upper paretic limb in acute or sub-acute stroke : a systematic review

    NARCIS (Netherlands)

    Nijland, Rinske; Kwakkel, Gert; Bakers, Japie; van Wegen, Erwin

    2011-01-01

    Constraint-induced movement therapy is a commonly used intervention to improve upper limb function after stroke. However, the effectiveness of constraint-induced movement therapy and its optimal dosage during acute or sub-acute stroke is still under debate. To examine the literature on the effects

  5. Interventions for dysarthria due to stroke and other adult-acquired, non-progressive brain injury.

    Science.gov (United States)

    Mitchell, Claire; Bowen, Audrey; Tyson, Sarah; Butterfint, Zoe; Conroy, Paul

    2017-01-25

    Dysarthria is an acquired speech disorder following neurological injury that reduces intelligibility of speech due to weak, imprecise, slow and/or unco-ordinated muscle control. The impact of dysarthria goes beyond communication and affects psychosocial functioning. This is an update of a review previously published in 2005. The scope has been broadened to include additional interventions, and the title amended accordingly. To assess the effects of interventions to improve dysarthric speech following stroke and other non-progressive adult-acquired brain injury such as trauma, infection, tumour and surgery. We searched the Cochrane Stroke Group Trials Register (May 2016), CENTRAL (Cochrane Library 2016, Issue 4), MEDLINE, Embase, and CINAHL on 6 May 2016. We also searched Linguistics and Language Behavioral Abstracts (LLBA) (1976 to November 2016) and PsycINFO (1800 to September 2016). To identify further published, unpublished and ongoing trials, we searched major trials registers: WHO ICTRP, the ISRCTN registry, and ClinicalTrials.gov. We also handsearched the reference lists of relevant articles and contacted academic institutions and other researchers regarding other published, unpublished or ongoing trials. We did not impose any language restrictions. We selected randomised controlled trials (RCTs) comparing dysarthria interventions with 1) no intervention, 2) another intervention for dysarthria (this intervention may differ in methodology, timing of delivery, duration, frequency or theory), or 3) an attention control. Three review authors selected trials for inclusion, extracted data, and assessed risk of bias. We attempted to contact study authors for clarification and missing data as required. We calculated standardised mean difference (SMD) and 95% confidence interval (CI), using a random-effects model, and performed sensitivity analyses to assess the influence of methodological quality. We planned to conduct subgroup analyses for underlying clinical

  6. Moving Forward By Stimulating the Brain: Transcranial Direct Current Stimulation in Post-Stroke Hemiparesis: A Mini Review

    Directory of Open Access Journals (Sweden)

    Heather T. Peters

    2016-08-01

    Full Text Available Stroke remains a leading cause of disability worldwide, with a majority of survivors experiencing long term decrements in motor function that severely undermine quality of life. While many treatment approaches and adjunctive strategies exist to remediate motor impairment, many are only efficacious or feasible for survivors with active hand and wrist function, a population who constitute only a minority of stroke survivors. Transcranial direct current stimulation (tDCS, a type of noninvasive brain stimulation, has been increasingly utilized to increase motor function following stroke as it is able to be used with stroke survivors of varying impairment levels, is portable, is relatively inexpensive and has few side effects and contraindications. Accordingly, in recent years the number of studies investigating its efficacy when utilized as an adjunct to motor rehabilitation regimens has drastically increased. While many of these trials have reported positive and promising efficacy, methodologies vary greatly between studies, including differences in stimulation parameters, outcome measures and the nature of physical practice. As such, an urgent need remains, centering on the need to investigate these methodological differences and synthesize the most current evidence surrounding the application of tDCS for post-stroke motor rehabilitation. Accordingly, the purpose of this paper is to provide a detailed overview of the most recent tDCS literature (published 2014-2015, while highlighting these variations in methodological approach, as well to elucidate the mechanisms associated with tDCS and post-stroke motor re-learning and neuroplasticity.

  7. Individualized model predicts brain current flow during transcranial direct-current stimulation treatment in responsive stroke patient.

    Science.gov (United States)

    Datta, Abhishek; Baker, Julie M; Bikson, Marom; Fridriksson, Julius

    2011-07-01

    Although numerous published reports have demonstrated the beneficial effects of transcranial direct-current stimulation (tDCS) on task performance, fundamental questions remain regarding the optimal electrode configuration on the scalp. Moreover, it is expected that lesioned brain tissue will influence current flow and should therefore be considered (and perhaps leveraged) in the design of individualized tDCS therapies for stroke. The current report demonstrates how different electrode configurations influence the flow of electrical current through brain tissue in a patient who responded positively to a tDCS treatment targeting aphasia. The patient, a 60-year-old man, sustained a left hemisphere ischemic stroke (lesion size = 87.42 mL) 64 months before his participation. In this study, we present results from the first high-resolution (1 mm(3)) model of tDCS in a brain with considerable stroke-related damage; the model was individualized for the patient who received anodal tDCS to his left frontal cortex with the reference cathode electrode placed on his right shoulder. We modeled the resulting brain current flow and also considered three additional reference electrode positions: right mastoid, right orbitofrontal cortex, and a "mirror" configuration with the anode over the undamaged right cortex. Our results demonstrate the profound effect of lesioned tissue on resulting current flow and the ability to modulate current pattern through the brain, including perilesional regions, through electrode montage design. The complexity of brain current flow modulation by detailed normal and pathologic anatomy suggest: (1) That computational models are critical for the rational interpretation and design of individualized tDCS stroke-therapy; and (2) These models must accurately reproduce head anatomy as shown here. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Subacute brain atrophy induced by radiation therapy to the malignant brain tumors

    International Nuclear Information System (INIS)

    Asai, Akio; Matsutani, Masao; Takakura, Kintomo.

    1987-01-01

    In order to analyze brain atrophy after radiation therapy to the brain tumors, we calculated a CSF-cranial volume ratio on CT scan as an index of brain atrophy, and estimated dementia-score by Hasegawa's method in 91 post-irradiated patients with malignant brain tumors. Radiation-induced brain atrophy was observed in 51 out of 91 patients (56 %) and dementia in 23 out of 47 patients (49 %). These two conditions were closely related, and observed significantly more often in aged and whole-brain-irradiated patients. As radiation-induced brain atrophy accompanied by dementia appeared 2 - 3 months after the completion of radiation therapy, it should be regarded as a subacute brain injury caused by radiation therapy. (author)

  9. Aerobic stimulus induced by virtual reality games in stroke survivors.

    Science.gov (United States)

    Silva de Sousa, Julio Cesar; Torriani-Pasin, Camila; Tosi, Amanda Barboza; Fecchio, Rafael Yokoyama; Riani da Costa, Luiz Augusto; Forjaz, Cláudia Lúcia de Moraes

    2018-02-08

    To evaluate whether virtual reality games (VRG) in stroke survivors produce significant and reproducible heart rate (HR) and oxygen consumption (VO 2 ) responses during their execution, corresponding to an intensity between the anaerobic threshold (AT) and the respiratory compensation point (RCP). Single subjects repeated measure design SETTING: Stroke survivors registered from a rehabilitation program PARTICIPANTS: Twelve chronic hemiparetic stroke survivors (10 men, 58 ± 12 years) rated at 3 or 4 in the Functional Ambulation Categories (FAC). Subjects underwent, in a random order, two identical sessions of VRG (console Xbox360+Kinect) and one control session (CONT - 38 min watching a movie). The VRG sessions were composed by four sets of VRG (3 min of Boxing, 1 min for changing the game and 4 min of Tennis) interspaced by 2 min of rest. HR and VO 2 were measured during the experimental sessions and compared to HR and VO 2 obtained at AT and RCP assessed in a maximal cardiopulmonary exercise test. HR and VO 2 during VRG presented good reproducibility (intraclass correlation coefficient > 0.91 and > 0.85 and coefficient of variation games of the console XBox360+Kinect promotes reproducible responses of HR and VO 2 that corresponded, respectively, to AT and below AT, characterizing a low intensity aerobic stimulus. Copyright © 2018. Published by Elsevier Inc.

  10. Cryptogenic Stroke

    Directory of Open Access Journals (Sweden)

    Mohammad Saadatnia

    2017-02-01

    Full Text Available Cryptogenic stroke is defined as brain infarction that is not attributable to a source of definite embolism, large artery atherosclerosis, or small artery disease despite a thorough vascular, cardiac, and serologic evaluation. Despite many advances in our understanding of ischemic stroke, cryptogenic strokes remain a diagnostic and therapeutic challenge. The pathophysiology of cryptogenic stroke is likely various. Probable mechanisms include cardiac embolism secondary to occult paroxysmal atrial fibrillation, aortic atheromatous disease or other cardiac sources, paradoxical embolism from atrial septal abnormalities such as patent foramen ovale, hypercoagulable states, and preclinical or subclinical cerebrovascular disease.  Cryptogenic stroke is one-fourth among cerebral infarction, but most of them could be ascribed to embolic stroke. A significant proportion of cryptogenic strokes adhere to embolic infarct topography on brain imaging and improvement in our ability to detect paroxysmal atrial fibrillation in patients with cryptogenic stroke has strengthened the idea that these strokes are embolic in nature. a significant proportion of cryptogenic strokes adhere to embolic infarct topography on brain imaging.embolic stroke of undetermined sources(ESUS was planned for unifying embolic stroke of undetermined source.  The etiologies underlying ESUS included minor-risk potential cardioembolic sources, covert paroxysmal atrial fibrillation, cancer-associated coagulopathy and embolism, arteriogenic emboli, and paroxysmal embolism. Extensive evaluation including transesophageal echocardiography and cardiac monitoring for long time could identify the etiology of these patients. Therefore cryptogenic stroke is a diagnosis of exclusion. Compared with other stroke subtypes, cryptogenic stroke tends to have a better prognosis and lower long-term risk of recurrence.

  11. Peak plasma interleukin-6 and other peripheral markers of inflammation in the first week of ischaemic stroke correlate with brain infarct volume, stroke severity and long-term outcome

    Directory of Open Access Journals (Sweden)

    del Zoppo Gregory J

    2004-01-01

    Full Text Available Abstract Background Cerebral ischaemia initiates an inflammatory response in the brain and periphery. We assessed the relationship between peak values of plasma interleukin-6 (IL-6 in the first week after ischaemic stroke, with measures of stroke severity and outcome. Methods Thirty-seven patients with ischaemic stroke were prospectively recruited. Plasma IL-6, and other markers of peripheral inflammation, were measured at pre-determined timepoints in the first week after stroke onset. Primary analyses were the association between peak plasma IL-6 concentration with both modified Rankin score (mRS at 3 months and computed tomography (CT brain infarct volume. Results Peak plasma IL-6 concentration correlated significantly (p Conclusions These data provide evidence that the magnitude of the peripheral inflammatory response is related to the severity of acute ischaemic stroke, and clinical outcome.

  12. Clinical relevance of cortical spreading depression in neurological disorders: migraine, malignant stroke, subarachnoid and intracranial hemorrhage, and traumatic brain injury

    DEFF Research Database (Denmark)

    Lauritzen, Martin; Dreier, Jens Peter; Fabricius, Martin

    2011-01-01

    to suggest that CSD is involved in the mechanism of migraine, stroke, subarachnoid hemorrhage and traumatic brain injury. The implications of these findings are widespread and suggest that intrinsic brain mechanisms have the potential to worsen the outcome of cerebrovascular episodes or brain trauma...... as a pathophysiological mechanism for this group of acute neurological disorders. The findings have implications for monitoring and treatment of patients with acute brain disorders in the intensive care unit. Drawing on the large body of experimental findings from animal studies of CSD obtained during decades we suggest...... treatment strategies, which may be used to prevent or attenuate secondary neuronal damage in acutely injured human brain cortex caused by depolarization waves....

  13. Stroke increases g protein-coupled estrogen receptor expression in the brain of male but not female mice.

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    Broughton, Brad R S; Brait, Vanessa H; Guida, Elizabeth; Lee, Seyoung; Arumugam, Thiruma V; Gardiner-Mann, Chantelle V; Miller, Alyson A; Tang, Sung-Chun; Drummond, Grant R; Sobey, Christopher G

    2013-01-01

    The novel estrogen receptor, G protein-coupled estrogen receptor (GPER, previously named GPR30), is widely distributed throughout the male and female brain and, thus, could potentially play a role in estrogen-mediated neuroprotective effects in diseases such as stroke. We hypothesized that GPER distribution and expression in the brain of male, intact female, and ovariectomized (OVX) mice is increased after 0.5 h middle cerebral artery occlusion. Using immunohistochemistry, we found that ischemia reperfusion increased GPER distribution in the peri-infarct brain regions of male mice, but surprisingly not in intact females or OVX mice. Similar differences were observed in the male and female human brain after stroke. In contrast, GPER distribution was decreased in the infarct core of all mice examined. Furthermore, GPER immunofluorescence was co-localized with the endothelial cell marker, von Willebrand factor, and the neuronal marker, NeuN. Consistent with the immunohistochemical findings, Western blot analysis showed GPER expression is only elevated in the ischemic hemisphere of male mice. Moreover, GPER mRNA expression in males was elevated at 4 h but had returned to baseline by 24 h. In conclusion, these findings indicate that GPER may be a potential therapeutic target after stroke, especially in males, in whom estrogen therapy is not feasible. Copyright © 2012 S. Karger AG, Basel.

  14. Management of Brain Arteriovenous Malformations: A Scientific Statement for Healthcare Professionals From the American Heart Association/American Stroke Association.

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    Derdeyn, Colin P; Zipfel, Gregory J; Albuquerque, Felipe C; Cooke, Daniel L; Feldmann, Edward; Sheehan, Jason P; Torner, James C

    2017-08-01

    The aim of this statement is to review the current data and to make suggestions for the diagnosis and management of both ruptured and unruptured brain arteriovenous malformations. The writing group met in person and by teleconference to establish search terms and to discuss narrative text and suggestions. Authors performed their own literature searches of PubMed, Medline, or Embase, specific to their allocated section, through the end of January 2015. Prerelease review of the draft statement was performed by expert peer reviewers and by the members of the Stroke Council Scientific Oversight Committee and Stroke Council Leadership Committee. The focus of the scientific statement was subdivided into epidemiology; diagnosis; natural history; treatment, including the roles of surgery, stereotactic radiosurgery, and embolization; and management of ruptured and unruptured brain arteriovenous malformations. Areas requiring more evidence were identified. Brain arteriovenous malformations are a relatively uncommon but important cause of hemorrhagic stroke, especially in young adults. This statement describes the current knowledge of the natural history and treatment of patients with ruptured and unruptured brain arteriovenous malformations, suggestions for management, and implications for future research. © 2017 American Heart Association, Inc.

  15. TGFβ signaling in the brain increases with aging and signals to astrocytes and innate immune cells in the weeks after stroke

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    Buckwalter Marion S

    2010-10-01

    Full Text Available Abstract Background TGFβ is both neuroprotective and a key immune system modulator and is likely to be an important target for future stroke therapy. The precise function of increased TGF-β1 after stroke is unknown and its pleiotropic nature means that it may convey a neuroprotective signal, orchestrate glial scarring or function as an important immune system regulator. We therefore investigated the time course and cell-specificity of TGFβ signaling after stroke, and whether its signaling pattern is altered by gender and aging. Methods We performed distal middle cerebral artery occlusion strokes on 5 and 18 month old TGFβ reporter mice to get a readout of TGFβ responses after stroke in real time. To determine which cell type is the source of increased TGFβ production after stroke, brain sections were stained with an anti-TGFβ antibody, colocalized with markers for reactive astrocytes, neurons, and activated microglia. To determine which cells are responding to TGFβ after stroke, brain sections were double-labelled with anti-pSmad2, a marker of TGFβ signaling, and markers of neurons, oligodendrocytes, endothelial cells, astrocytes and microglia. Results TGFβ signaling increased 2 fold after stroke, beginning on day 1 and peaking on day 7. This pattern of increase was preserved in old animals and absolute TGFβ signaling in the brain increased with age. Activated microglia and macrophages were the predominant source of increased TGFβ after stroke and astrocytes and activated microglia and macrophages demonstrated dramatic upregulation of TGFβ signaling after stroke. TGFβ signaling in neurons and oligodendrocytes did not undergo marked changes. Conclusions We found that TGFβ signaling increases with age and that astrocytes and activated microglia and macrophages are the main cell types that undergo increased TGFβ signaling in response to post-stroke increases in TGFβ. Therefore increased TGFβ after stroke likely regulates glial

  16. Hyperbaric Oxygen Therapy Can Induce Angiogenesis and Regeneration of Nerve Fibers in Traumatic Brain Injury Patients

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    Sigal Tal

    2017-10-01

    Full Text Available Background: Recent clinical studies in stroke and traumatic brain injury (TBI victims suffering chronic neurological injury present evidence that hyperbaric oxygen therapy (HBOT can induce neuroplasticity.Objective: To assess the neurotherapeutic effect of HBOT on prolonged post-concussion syndrome (PPCS due to TBI, using brain microstructure imaging.Methods: Fifteen patients afflicted with PPCS were treated with 60 daily HBOT sessions. Imaging evaluation was performed using Dynamic Susceptibility Contrast-Enhanced (DSC and Diffusion Tensor Imaging (DTI MR sequences. Cognitive evaluation was performed by an objective computerized battery (NeuroTrax.Results: HBOT was initiated 6 months to 27 years (10.3 ± 3.2 years from injury. After HBOT, DTI analysis showed significantly increased fractional anisotropy values and decreased mean diffusivity in both white and gray matter structures. In addition, the cerebral blood flow and volume were increased significantly. Clinically, HBOT induced significant improvement in the memory, executive functions, information processing speed and global cognitive scores.Conclusions: The mechanisms by which HBOT induces brain neuroplasticity can be demonstrated by highly sensitive MRI techniques of DSC and DTI. HBOT can induce cerebral angiogenesis and improve both white and gray microstructures indicating regeneration of nerve fibers. The micro structural changes correlate with the neurocognitive improvements.

  17. Characterizing relationships of DTI, fMRI, and motor recovery in stroke rehabilitation utilizing brain-computer interface technology.

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    Song, Jie; Young, Brittany M; Nigogosyan, Zack; Walton, Leo M; Nair, Veena A; Grogan, Scott W; Tyler, Mitchell E; Farrar-Edwards, Dorothy; Caldera, Kristin E; Sattin, Justin A; Williams, Justin C; Prabhakaran, Vivek

    2014-01-01

    The relationship of the structural integrity of white matter tracts and cortical activity to motor functional outcomes in stroke patients is of particular interest in understanding mechanisms of brain structural and functional changes while recovering from stroke. This study aims to probe these underlying mechanisms using diffusion tensor imaging (DTI) and fMRI measures. We examined the structural integrity of the posterior limb of the internal capsule (PLIC) using DTI and corticomotor activity using motor-task fMRI in stroke patients who completed up to 15 sessions of rehabilitation therapy using Brain-Computer Interface (BCI) technology. We hypothesized that (1) the structural integrity of PLIC and corticomotor activity are affected by stroke; (2) changes in structural integrity and corticomotor activity following BCI intervention are related to motor recovery; (3) there is a potential relationship between structural integrity and corticomotor activity. We found that (1) the ipsilesional PLIC showed significantly decreased fractional anisotropy (FA) values when compared to the contralesional PLIC; (2) lower ipsilesional PLIC-FA values were significantly associated with worse motor outcomes (i.e., ipsilesional PLIC-FA and motor outcomes were positively correlated.); (3) lower ipsilesional PLIC-FA values were significantly associated with greater ipsilesional corticomotor activity during impaired-finger-tapping-task fMRI (i.e., ipsilesional PLIC-FA and ipsilesional corticomotor activity were negatively correlated), with an overall bilateral pattern of corticomotor activity observed; and (4) baseline FA values predicted motor recovery assessed after BCI intervention. These findings suggest that (1) greater vs. lesser microstructural integrity of the ipsilesional PLIC may contribute toward better vs. poor motor recovery respectively in the stroke-affected limb and demand lesser vs. greater cortical activity respectively from the ipsilesional motor cortex; and that (2

  18. Anti-Inflammation of Natural Components from Medicinal Plants at Low Concentrations in Brain via Inhibiting Neutrophil Infiltration after Stroke

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    Jiannan Chen

    2016-01-01

    Full Text Available Inflammation after stroke consists of activation of microglia/astrocytes in situ and infiltration of blood-borne leukocytes, resulting in brain damage and neurological deficits. Mounting data demonstrated that most natural components from medicinal plants had anti-inflammatory effects after ischemic stroke through inhibiting activation of resident microglia/astrocytes within ischemic area. However, it is speculated that this classical activity cannot account for the anti-inflammatory function of these natural components in the cerebral parenchyma, where they are detected at very low concentrations due to their poor membrane permeability and slight leakage of BBB. Could these drugs exert anti-inflammatory effects peripherally without being delivered across the BBB? Factually, ameliorating blood-borne neutrophil recruitment in peripheral circulatory system has been proved to reduce ischemic damage and improve outcomes. Thus, it is concluded that if drugs could achieve effective concentrations in the cerebral parenchyma, they can function via crippling resident microglia/astrocytes activation and inhibiting neutrophil infiltration, whereas the latter will be dominating when these drugs localize in the brain at a low concentration. In this review, the availability of some natural components crossing the BBB in stroke will be discussed, and how these drugs lead to improvements in stroke through inhibition of neutrophil rolling, adhesion, and transmigration will be illustrated.

  19. Longitudinal Brain Functional Connectivity Changes of the Cortical Motor-Related Network in Subcortical Stroke Patients with Acupuncture Treatment

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    Yongxin Li

    2017-01-01

    Full Text Available In clinical practice, the effectiveness of the rehabilitation therapy such as acupuncture combining conventional Western medicine (AG on stroke people’s motor-related brain network and their behaviors has not been systematically studied. In the present study, seventeen adult ischemic patients were collected and divided into two groups: the conventional Western medicine treatment group (CG and the AG. The neurological deficit scores (NDS and resting-state functional MRI data were collected before and after treatment. Compared with the CG patients, AG patients exhibited a significant enhancement of the percent changes of NDS from pre- to posttreatment intervention. All patients showed significant changes of functional connectivity (FC between the pair of cortical motor-related regions. After treatment, both patient groups showed a recovery of brain connectivity to the nearly normal level compared with the controls in these pairs. Moreover, a significant correlation between the percent changes of NDS and the pretreatment FC values of bilateral primary motor cortex (M1 in all patients was found. In conclusion, our results showed that AG therapy can be an effective means for ischemic stroke patients to recover their motor function ability. The FC strengths between bilateral M1 of stroke patients can predict stroke patients’ treatment outcome after rehabilitation therapy.

  20. Associations of Circulating GDF-15 and ST2 concentrations with Subclinical Vascular Brain Injury and Incident Stroke

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    Andersson, Charlotte; Preis, Sarah R.; Beiser, Alexa; DeCarli, Charles; Wollert, Kai C.; Wang, Thomas J; Januzzi, James L.; Vasan, Ramachandran S; Seshadri, Sudha

    2015-01-01

    Background and Purpose Growth differentiation factor-15 (GDF-15) and soluble (s)ST2 are markers of cardiac and vascular stress. We investigated the associations between circulating concentrations of these biomarkers and incident stroke and subclinical vascular brain injury in a sample from the Framingham Offspring cohort. Methods We followed 3374 stroke- and dementia-free individuals (mean age 59.0±9.7 years, 53% women) attending the Framingham Offspring 6th examination cycle 11.8±3.0 years for incident stroke. A subsample of 2463 individuals underwent brain magnetic resonance imaging and neuropsychological testing approximately 4.0±1.7 years after the 6th examination. Results After adjustment for traditional cardiovascular risk factors, B-type natriuretic peptide, high-sensitivity C-reactive protein, and urine albumin levels, higher stress biomarker levels were associated cross-sectionally with lower brain volumes (βs for intracranial volume comparing 4rth [Q4] vs. 1st biomarker [Q1] quartiles −0.71% for GDF-15, p=0.002, and 0.47% for sST2, p=0.02) and worse performance on the visual reproduction test (βs for Q4 vs. Q1=−0.62 for GDF-15, p=0.009, and −0.40 for sST2, p=0.04). Higher GDF-15 concentrations were also associated with greater log-transformed white-matter hyperintensity volumes (β for Q4 vs. Q1=0.19, p=0.01). Prospectively, a total of 203 (6%) individuals developed incident stroke/transient ischemic attack (TIA) during follow-up. After multivariable adjustment, sST2 remained significantly associated with stroke/TIA, hazard ratio for Q4 vs. Q1 of 1.76, 95% confidence interval 1.06–2.92, p=0.03. Conclusions Circulating GDF-15 and sST2 are associated with subclinical brain injury and cognitive impairment. Higher sST2 concentrations are also associated with incident stroke, suggesting potential links between cardiac stress biomarkers and brain injury. PMID:26219649

  1. Robotics, stem cells, and brain-computer interfaces in rehabilitation and recovery from stroke: updates and advances.

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    Boninger, Michael L; Wechsler, Lawrence R; Stein, Joel

    2014-11-01

    The aim of this study was to describe the current state and latest advances in robotics, stem cells, and brain-computer interfaces in rehabilitation and recovery for stroke. The authors of this summary recently reviewed this work as part of a national presentation. The article represents the information included in each area. Each area has seen great advances and challenges as products move to market and experiments are ongoing. Robotics, stem cells, and brain-computer interfaces all have tremendous potential to reduce disability and lead to better outcomes for patients with stroke. Continued research and investment will be needed as the field moves forward. With this investment, the potential for recovery of function is likely substantial.

  2. Effects of the Treatment with ‍Nigella sativa Oil on Brain Injury and Edema in Experimental Model of Stroke in Rats

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    H Panahpour

    2015-09-01

    Full Text Available Background & objectives: Stroke is third leading cause of death and disability in the most of human communities. The use of herbs and medicinal plants in different countries is increasing. Today, herbal medicine is used as alternative or complementary therapies with a fewer side effects. Nigella sativa has a rich medical and religious history. Oxidative stress has important role in the pathophysiology of stroke. As Nigella sativa has antioxidant effects, its administration may produce a protective effect against complications of this disease. We examined the effects of the treatment with Nigella sativa oil on the cerebral infarction and edema. Methods: 48 Male Sprague-Dawley rats were divided into three groups, sham, control ischemic and Nigella sativa oil treated (2 ml/kg ischemic groups. Transient focal cerebral ischemia was induced by 90-min-long occlusion of the left middle cerebral artery followed by 24-h-long reperfusion. Neurological deficit score was evaluated at the end of the reperfusion period. Thereafter, the animals were randomly selected and used for two projects: (i Measurement of the infarct volumes and neurological outcome (ii investigation of ischemic brain edema formation using a wet/dry method. Results: Induction of cerebral ischemia in the control group produced considerable brain infarction in conjunction with impaired motor functions and severely brain edema. Treatment with Nigella sativa oil significantly reduced the infarct volume and improved the motor functions. The water content in the left (lesioned hemisphere was considerably elevated in the control ischemic group. Administration of the Nigella sativa oil significantly lowered the water content in the ischemic lesioned hemisphere. Conclusion: Treatment with Nigella sativa oil can noticeably decrease the ischemic brain injury, attenuate edema formation and improve motor disabilities.

  3. Dizziness in stroke

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    M. V. Zamergrad

    2015-01-01

    Full Text Available Differential diagnosis of new-onset acute vestibular vertigo is chiefly made between vestibular neuronitis and stroke. Dizziness in stroke is usually accompanied by other focal neurological symptoms of brainstem and cerebellar involvement. However, stroke may appear as isolated vestibular vertigo in some cases. An analysis of history data and the results of neurovestibular examination and brain magnetic resonance imaging allows stroke to be diagnosed in patients with acute isolated dizziness. The treatment of patients with stroke-induced dizziness involves a wide range of medications for the reduction of the degree of dizziness and unsteadiness and for the secondary prevention of stroke. Vestibular rehabilitation is an important component of treatment. The paper describes an observation of a patient with poorly controlled hypertension, who developed new-onset acute systemic dizziness. Vestibular neuronitis might be presumed to be a peripheral cause of vestibular disorders, by taking into account the absence of additional obvious neurological symptoms (such as pareses, defective sensation, diplopia, etc. and the nature of nystagmus. However, intention tremor in fingernose and heel-knee tests on the left side, a negative Halmagyi test, and results of Romberg’s test could suggest that stroke was a cause ofdizziness.

  4. Dual activities of the anti-cancer drug candidate PBI-05204 provide neuroprotection in brain slice models for neurodegenerative diseases and stroke.

    Science.gov (United States)

    Van Kanegan, Michael J; Dunn, Denise E; Kaltenbach, Linda S; Shah, Bijal; He, Dong Ning; McCoy, Daniel D; Yang, Peiying; Peng, Jiangnan; Shen, Li; Du, Lin; Cichewicz, Robert H; Newman, Robert A; Lo, Donald C

    2016-05-12

    We previously reported neuroprotective activity of the botanical anti-cancer drug candidate PBI-05204, a supercritical CO2 extract of Nerium oleander, in brain slice and in vivo models of ischemic stroke. We showed that one component of this neuroprotective activity is mediated through its principal cardiac glycoside constituent, oleandrin, via induction of the potent neurotrophic factor brain-derived neurotrophic factor (BDNF). However, we also noted that the concentration-relation for PBI-05204 in the brain slice oxygen-glucose deprivation (OGD) model is considerably broader than that for oleandrin as a single agent. We thus surmised that PBI-05204 contains an additional neuroprotective component(s), distinct from oleandrin. We report here that neuroprotective activity is also provided by the triterpenoid constituents of PBI-05204, notably oleanolic acid. We demonstrate that a sub-fraction of PBI-05204 (Fraction 0-4) containing oleanolic and other triterpenoids, but without cardiac glycosides, induces the expression of cellular antioxidant gene transcription programs regulated through antioxidant transcriptional response elements (AREs). Finally, we show that Fraction 0-4 provides broad neuroprotection in organotypic brain slice models for neurodegeneration driven by amyloid precursor protein (APP) and tau implicated in Alzheimer's disease and frontotemporal dementias, respectively, in addition to ischemic injury modeled by OGD.

  5. Low-level light emitting diode (LED) therapy suppresses inflammasome-mediated brain damage in experimental ischemic stroke.

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    Lee, Hae In; Lee, Sae-Won; Kim, Nam Gyun; Park, Kyoung-Jun; Choi, Byung Tae; Shin, Yong-Il; Shin, Hwa Kyoung

    2017-11-01

    Use of photostimulation including low-level light emitting diode (LED) therapy has broadened greatly in recent years because it is compact, portable, and easy to use. Here, the effects of photostimulation by LED (610 nm) therapy on ischemic brain damage was investigated in mice in which treatment started after a stroke in a clinically relevant setting. The mice underwent LED therapy (20 min) twice a day for 3 days, commencing at 4 hours post-ischemia. LED therapy group generated a significantly smaller infarct size and improvements in neurological function based on neurologic test score. LED therapy profoundly reduced neuroinflammatory responses including neutrophil infiltration and microglia activation in the ischemic cortex. LED therapy also decreased cell death and attenuated the NLRP3 inflammasome, in accordance with down-regulation of pro-inflammatory cytokines IL-1β and IL-18 in the ischemic brain. Moreover, the mice with post-ischemic LED therapy showed suppressed TLR-2 levels, MAPK signaling and NF-kB activation. These findings suggest that by suppressing the inflammasome, LED therapy can attenuate neuroinflammatory responses and tissue damage following ischemic stroke. Therapeutic interventions targeting the inflammasome via photostimulation with LED may be a novel approach to ameliorate brain injury following ischemic stroke. Effect of post-ischemic low-level light emitting diode therapy (LED-T) on infarct reduction was mediated by inflammasome suppression. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Traumatic brain injury-induced sleep disorders

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    Viola-Saltzman M

    2016-02-01

    Full Text Available Mari Viola-Saltzman, Camelia Musleh Department of Neurology, NorthShore University HealthSystem, Evanston, IL, USA Abstract: Sleep disturbances are frequently identified following traumatic brain injury, affecting 30%–70% of persons, and often occur after mild head injury. Insomnia, fatigue, and sleepiness are the most frequent sleep complaints after traumatic brain injury. Sleep apnea, narcolepsy, periodic limb movement disorder, and parasomnias may also occur after a head injury. In addition, depression, anxiety, and pain are common brain injury comorbidities with significant influence on sleep quality. Two types of traumatic brain injury that may negatively impact sleep are acceleration/deceleration injuries causing generalized brain damage and contact injuries causing focal brain damage. Polysomnography, multiple sleep latency testing, and/or actigraphy may be utilized to diagnose sleep disorders after a head injury. Depending on the disorder, treatment may include the use of medications, positive airway pressure, and/or behavioral modifications. Unfortunately, the treatment of sleep disorders associated with traumatic brain injury may not improve neuropsychological function or sleepiness. Keywords: traumatic brain injury, insomnia, hypersomnia, sleep apnea, periodic limb movement disorder, fatigue

  7. Correlation between urinary incontinence and localization of brain lesion and severity of neurological lesion caused by a stroke

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    Vetra A.

    2012-10-01

    Full Text Available Urinary incontinence is one of the medical problems, which may develop as a result of a stroke, and, according to several authors, its occurrence frequency may reach up to 80%. Clinical symptoms of urinary incontinence are considered to be one of the symptoms, which, along with the severity of the stroke and the level of functional limitations, allows to develop reliable predictions and to make targeted use of resources. Aim of the study, materials and methods. The aim of the study is to explore whether post-stroke urinary incontinence correlates with localization of lesion and clinical symptoms. The study includes 180 patients after a stroke, who have received treatment at Riga Eastern Clinic University Hospital Stroke Unit. All had a comprehensive clinical and functional assessment and cerebral computed tomography (CT. The examination took place at the hospital a few days after the stroke had occurred. Results. There are 180 participants to the study. Symptoms of urinary incontinence were reported for 70.6% of study participants. In 64% of cases new incontinence problems had developed, while in 6.5% of cases the previous symptoms of urinary incontinence (prior to the stroke had worsened. The most common types of urinary incontinence in the acute period were urge and mixed incontinence (functional and urge incontinence. Patients with low Barthel Index showed higher frequency of urinary incontinence. A comparison of patient groups with and without symptoms of urinary incontinence showed that patients older than 75 years showed more symptoms of urinary incontinence (p = 0.013, and the same can be said about patients with low indicators of Barthel (p = 0.001 and patients with cognitive disorders (p = 0.001. Severity of paresis, aphasia and sensory disorders show a reliable correlation with the type of urinary incontinence. Conclusion. Symptoms of post-stroke urinary incontinence are linked both to a person's age, and functional and cognitive

  8. Synergistic Association of Valproate and Resveratrol Reduces Brain Injury in Ischemic Stroke

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    Lara Faggi

    2018-01-01

    Full Text Available Histone deacetylation, together with altered acetylation of NF-κB/RelA, encompassing the K310 residue acetylation, occur during brain ischemia. By restoring the normal acetylation condition, we previously reported that sub-threshold doses of resveratrol and entinostat (MS-275, respectively, an activator of the AMP-activated kinase (AMPK-sirtuin 1 pathway and an inhibitor of class I histone deacetylases (HDACs, synergistically elicited neuroprotection in a mouse model of ischemic stroke. To improve the translational power of this approach, we investigated the efficacy of MS-275 replacement with valproate, the antiepileptic drug also reported to be a class I HDAC blocker. In cortical neurons previously exposed to oxygen glucose deprivation (OGD, valproate elicited neuroprotection at 100 nmol/mL concentration when used alone and at 1 nmol/mL concentration when associated with resveratrol (3 nmol/mL. Resveratrol and valproate restored the acetylation of histone H3 (K9/18, and they reduced the RelA(K310 acetylation and the Bim level in neurons exposed to OGD. Chromatin immunoprecipitation analysis showed that the synergistic drug association impaired the RelA binding to the Bim promoter, as well as the promoter-specific H3 (K9/18 acetylation. In mice subjected to 60 min of middle cerebral artery occlusion (MCAO, the association of resveratrol 680 µg/kg and valproate 200 µg/kg significantly reduced the infarct volume as well as the neurological deficits. The present study suggests that valproate and resveratrol may represent a promising ready-to-use strategy to treat post-ischemic brain damage.

  9. Increased brain damage after ischaemic stroke in mice lacking the chemokine receptor CCR5

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    Sorce, S; Bonnefont, J; Julien, S; Marq-Lin, N; Rodriguez, I; Dubois-Dauphin, M; Krause, KH

    2010-01-01

    Background and purpose: The chemokine receptor CCR5 is well known for its function in immune cells; however, it is also expressed in the brain, where its specific role remains to be elucidated. Because genetic factors may influence the risk of developing cerebral ischaemia or affect its clinical outcome, we have analysed the role of CCR5 in experimental stroke. Experimental approach: Permanent cerebral ischaemia was performed by occlusion of the middle cerebral artery in wild-type and CCR5-deficient mice. Locomotor behaviour, infarct size and histochemical alterations were analysed at different time points after occlusion. Key results: The cerebral vasculature was comparable in wild-type and CCR5-deficient mice. However, the size of the infarct and the motor deficits after occlusion were markedly increased in CCR5-deficient mice as compared with wild type. No differences between wild-type and CCR5-deficient mice were elicited by occlusion with respect to the morphology and abundance of astrocytes and microglia. Seven days after occlusion the majority of CCR5-deficient mice displayed neutrophil invasion in the infarct region, which was not observed in wild type. As compared with wild type, the infarct regions of CCR5-deficient mice were characterized by increased neuronal death. Conclusions and implications: Lack of CCR5 increased the severity of brain injury following occlusion of the middle cerebral artery. This is of particular interest with respect to the relatively frequent occurrence of CCR5 deficiency in the human population (1–2% of the Caucasian population) and the advent of CCR5 inhibitors as novel drugs. PMID:20423342

  10. Role of histidine/histamine in carnosine-induced neuroprotection during ischemic brain damage.

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    Bae, Ok-Nam; Majid, Arshad

    2013-08-21

    Urgent need exists for new therapeutic options in ischemic stroke. We recently demonstrated that carnosine, an endogenous dipeptide consisting of alanine and histidine, is robustly neuroprotective in ischemic brain injury and has a wide clinically relevant therapeutic time window. The precise mechanistic pathways that mediate this neuroprotective effect are not known. Following in vivo administration, carnosine is hydrolyzed into histidine, a precursor of histamine. It has been hypothesized that carnosine may exert its neuroprotective activities through the histidine/histamine pathway. Herein, we investigated whether the neuroprotective effect of carnosine is mediated by the histidine/histamine pathway using in vitro primary astrocytes and cortical neurons, and an in vivo rat model of ischemic stroke. In primary astrocytes, carnosine significantly reduced ischemic cell death after oxygen-glucose deprivation, and this effect was abolished by histamine receptor type I antagonist. However, histidine or histamine did not exhibit a protective effect on ischemic astrocytic cell death. In primary neuronal cultures, carnosine was found to be neuroprotective but histamine receptor antagonists had no effect on the extent of neuroprotection. The in vivo effect of histidine and carnosine was compared using a rat model of ischemic stroke; only carnosine exhibited neuroprotection. Taken together, our data demonstrate that although the protective effects of carnosine may be partially mediated by activity at the histamine type 1 receptor on astrocytes, the histidine/histamine pathway does not appear to play a critical role in carnosine induced neuroprotection. Copyright © 2013. Published by Elsevier B.V.

  11. Cerebroprotective Effect of Moringa oleifera against Focal Ischemic Stroke Induced by Middle Cerebral Artery Occlusion

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    Woranan Kirisattayakul

    2013-01-01

    Full Text Available The protection against ischemic stroke is still required due to the limitation of therapeutic efficacy. Based on the role of oxidative stress in stroke pathophysiology, we determined whether Moringa oleifera, a plant possessing potent antioxidant activity, protected against brain damage and oxidative stress in animal model of focal stroke. M. oleifera leaves extract at doses of 100, 200 and 400 mg·kg−1 was orally given to male Wistar rats (300–350 g once daily at a period of 2 weeks before the occlusion of right middle cerebral artery (Rt.MCAO and 3 weeks after Rt.MCAO. The determinations of neurological score and temperature sensation were performed every 7 days throughout the study period, while the determinations of brain infarction volume, MDA level, and the activities of SOD, CAT, and GSH-Px were performed 24 hr after Rt.MCAO. The results showed that all doses of extract decreased infarction volume in both cortex and subcortex. The protective effect of medium and low doses of extract in all areas occurred mainly via the decreased oxidative stress. The protective effect of the high dose extract in striatum and hippocampus occurred via the same mechanism, whereas other mechanisms might play a crucial role in cortex. The detailed mechanism required further exploration.

  12. Environmental factors item development for persons with stroke, traumatic brain injury, and spinal cord injury.

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    Heinemann, Allen W; Magasi, Susan; Hammel, Joy; Carlozzi, Noelle E; Garcia, Sofia F; Hahn, Elizabeth A; Lai, Jin-Shei; Tulsky, David; Gray, David B; Hollingsworth, Holly; Jerousek, Sara

    2015-04-01

    To describe methods used in operationalizing environmental factors; to describe the results of a research project to develop measures of environmental factors that affect participation; and to define an initial item set of facilitators and barriers to participation after stroke, traumatic brain injury, and spinal cord injury. Instrument development included an extensive literature review, item classification and selection, item writing, and cognitive testing following the approach of the Patient-Reported Outcomes Measurement Information System. Community. Content area and outcome measurement experts (n=10) contributed to instrument development; individuals (n=200) with the target conditions participated in focus groups and in cognitive testing (n=15). None. Environmental factor items were categorized in 6 domains: assistive technology; built and natural environment; social environment; services, systems, and policies; access to information and technology; and economic quality of life. We binned 2273 items across the 6 domains, winnowed this pool to 291 items for cognitive testing, and recommended 274 items for pilot data collection. Five of the 6 domains correspond closely to the International Classification of Functioning, Disability and Health taxonomy of environmental factors; the sixth domain, economic quality of life, reflects an important construct that reflects financial resources that affect participation. Testing with a new and larger sample is underway to evaluate reliability, validity, and sensitivity. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  13. Neuroprotective effect of chondroitinase ABC on primary and secondary brain injury after stroke in hypertensive rats.

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    Chen, Xin-ran; Liao, Song-jie; Ye, Lan-xiang; Gong, Qiong; Ding, Qiao; Zeng, Jin-sheng; Yu, Jian

    2014-01-16

    Focal cerebral infarction causes secondary damage in the ipsilateral ventroposterior thalamic nucleus (VPN). Chondroitin sulfate proteoglycans (CSPGs) are a family of putative inhibitory components, and its degradation by chondroitinase ABC (ChABC) promotes post-injury neurogenesis. This study investigated the role of ChABC in the primary and secondary injury post stroke in hypertension. Renovascular hypertensive Sprague-Dawley rats underwent middle cerebral artery occlusion (MCAO), and were subjected to continuous intra-infarct infusion of ChABC (0.12 U/d for 7 days) 24 h later. Neurological function was evaluated by a modified neurologic severity score. Neurons were counted in the peri-infarct region and the ipsilateral VPN 8 and 14 days after MCAO by Nissl staining and NeuN labeling. The expressions of CSPGs, growth-associated protein-43 (GAP-43) and synaptophysin (SYN) were detected with immunofluorescence or Western blotting. The intra-infarct infusion of ChABC, by degrading accumulated CSPGs, rescued neuronal loss and increased the levels of GAP-43 and SYN in both the ipsilateral cortex and VPN, indicating enhancd neuron survival as well as augmented axonal growth and synaptic plasticity, eventually improving overall neurological function. The study demonstrated that intra-infarct ChABC infusion could salvage the brain from both primary and secondary injury by the intervention on the neuroinhibitory environment post focal cerebral infarction. © 2013 Published by Elsevier B.V.

  14. Brain-Computer Interfaces With Multi-Sensory Feedback for Stroke Rehabilitation: A Case Study.

    Science.gov (United States)

    Irimia, Danut C; Cho, Woosang; Ortner, Rupert; Allison, Brendan Z; Ignat, Bogdan E; Edlinger, Guenter; Guger, Christoph

    2017-11-01

    Conventional therapies do not provide paralyzed patients with closed-loop sensorimotor integration for motor rehabilitation. This work presents the recoveriX system, a hardware and software platform that combines a motor imagery (MI)-based brain-computer interface (BCI), functional electrical stimulation (FES), and visual feedback technologies for a complete sensorimotor closed-loop therapy system for poststroke rehabilitation. The proposed system was tested on two chronic stroke patients in a clinical environment. The patients were instructed to imagine the movement of either the left or right hand in random order. During these two MI tasks, two types of feedback were provided: a bar extending to the left or right side of a monitor as visual feedback and passive hand opening stimulated from FES as proprioceptive feedback. Both types of feedback relied on the BCI classification result achieved using common spatial patterns and a linear discriminant analysis classifier. After 10 sessions of recoveriX training, one patient partially regained control of wrist extension in her paretic wrist and the other patient increased the range of middle finger movement by 1 cm. A controlled group study is planned with a new version of the recoveriX system, which will have several improvements. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  15. Application of noninvasive brain stimulation for post-stroke dysphagia rehabilitation

    Directory of Open Access Journals (Sweden)

    Zhuo Wang

    2017-02-01

    Full Text Available Noninvasive brain stimulation (NIBS, commonly consisting of transcranial magnetic stimulation (TMS, transcranial direct-current stimulation (tDCS, as well as paired associative stimulation (PAS, has attracted increased interest and been applied experimentally in the treatment of post-stroke dysphagia (PSD. This review presented a synopsis of the current research for the application of NIBS on PSD. The intention here was to understand the current research progress and limitations in this field and to stimulate potential research questions not yet investigated for the application of NIBS on patients with PSD. Here we successively reviewed advances of repetitive TMS (rTMS, tDCS, and PAS techniques on both healthy participants and PSD patients in three aspects, including scientific researches about dysphagia mechanism, applied studies about stimulation parameters, and clinical trials about their therapeutic effects. The techniques of NIBS, especially rTMS, have been used by the researchers to explore the different mechanisms between swallowing recovery and extremity rehabilitation. The key findings included the important role of intact hemisphere reorganization for PSD recovery, and the use of NIBS on the contra-lesional side as a therapeutic potential for dysphagia rehabilitation. Though significant results were achieved in most studies by using NIBS on swallowing rehabilitation, it is still difficult to draw conclusions for the efficacy of these neurostimulation techniques, considering the great disparities between studies.

  16. Application of noninvasive brain stimulation for post-stroke dysphagia rehabilitation.

    Science.gov (United States)

    Wang, Zhuo; Song, Wei-Qun; Wang, Liang

    2017-02-01

    Noninvasive brain stimulation (NIBS), commonly consisting of transcranial magnetic stimulation (TMS), transcranial direct-current stimulation (tDCS), as well as paired associative stimulation (PAS), has attracted increased interest and been applied experimentally in the treatment of post-stroke dysphagia (PSD). This review presented a synopsis of the current research for the application of NIBS on PSD. The intention here was to understand the current research progress and limitations in this field and to stimulate potential research questions not yet investigated for the application of NIBS on patients with PSD. Here we successively reviewed advances of repetitive TMS (rTMS), tDCS, and PAS techniques on both healthy participants and PSD patients in three aspects, including scientific researches about dysphagia mechanism, applied studies about stimulation parameters, and clinical trials about their therapeutic effects. The techniques of NIBS, especially rTMS, have been used by the researchers to explore the different mechanisms between swallowing recovery and extremity rehabilitation. The key findings included the important role of intact hemisphere reorganization for PSD recovery, and the use of NIBS on the contra-lesional side as a therapeutic potential for dysphagia rehabilitation. Though significant results were achieved in most studies by using NIBS on swallowing rehabilitation, it is still difficult to draw conclusions for the efficacy of these neurostimulation techniques, considering the great disparities between studies. Copyright © 2016. Published by Elsevier Taiwan.

  17. Understanding Life After Stroke

    OpenAIRE

    Hjelmblink, Finn

    2008-01-01

    Stroke is an acute, neurological dysfunction of vascular origin with sudden occurrence and it influences physical, cognitive and psychological functions. Initial treatment aims at eliminating or reducing the brain damage. Soon, however, the influence of the stroke on the entire life of stroke survivors has to be considered. This thesis explores the meaning of life after stroke to 19 elderly stroke survivors during the first year post stroke. Survivors were interviewed twice and the interviews...

  18. Acute Inflammatory Response in Rodent Brain and Blood Following a Blast Induced Traumatic Brain Injury

    Science.gov (United States)

    2014-11-01

    dehydrated with 30% sucrose before storing at -80 °C. Thirty micron coronal sections were stained with a primary antibody against microglia ...strongly Iba-1 stained cells as compared to controls. These results indicate blast exposure induces activation of microglia in the hippocampus... Neuroinflammation after traumatic brain injury: Opportunities for therapeutic intervention. Brain, behaviour and Immunity 26: 1191-1201. Loane, D. J

  19. Acute ischemic stroke update.

    Science.gov (United States)

    Baldwin, Kathleen; Orr, Sean; Briand, Mary; Piazza, Carolyn; Veydt, Annita; McCoy, Stacey

    2010-05-01

    Stroke is the third most common cause of death in the United States and is the number one cause of long-term disability. Legislative mandates, largely the result of the American Heart Association, American Stroke Association, and Brain Attack Coalition working cooperatively, have resulted in nationwide standardization of care for patients who experience a stroke. Transport to a skilled facility that can provide optimal care, including immediate treatment to halt or reverse the damage caused by stroke, must occur swiftly. Admission to a certified stroke center is recommended for improving outcomes. Most strokes are ischemic in nature. Acute ischemic stroke is a heterogeneous group of vascular diseases, which makes targeted treatment challenging. To provide a thorough review of the literature since the 2007 acute ischemic stroke guidelines were developed, we performed a search of the MEDLINE database (January 1, 2004-July 1, 2009) for relevant English-language studies. Results (through July 1, 2009) from clinical trials included in the Internet Stroke Center registry were also accessed. Results from several pivotal studies have contributed to our knowledge of stroke. Additional data support the efficacy and safety of intravenous alteplase, the standard of care for acute ischemic stroke since 1995. Due to these study results, the American Stroke Association changed its recommendation to extend the time window for administration of intravenous alteplase from within 3 hours to 4.5 hours of symptom onset; this recommendation enables many more patients to receive the drug. Other findings included clinically useful biomarkers, the role of inflammation and infection, an expanded role for placement of intracranial stents, a reduced role for urgent carotid endarterectomy, alternative treatments for large-vessel disease, identification of nontraditional risk factors, including risk factors for women, and newly published pediatric stroke guidelines. In addition, new devices for

  20. Rat middle cerebral artery occlusion is not a suitable model for the study of stroke-induced spontaneous infections.

    Directory of Open Access Journals (Sweden)

    Mireia Campos-Martorell

    Full Text Available BACKGROUND: Infections related to stroke-induced immunodepression are an important complication causing a high rate of death in patients. Several experimental studies in mouse stroke models have described this process but it has never been tested in other species such as rats. METHODS: Our study focused on the appearance of secondary systemic and pulmonary infections in ischemic rats, comparing with sham and naive animals. For that purpose, male Wistar rats were subjected to embolic middle cerebral artery occlusion (eMCAO or to transient MCAO (tMCAO inserting a nylon filament. Forty-eight hours after ischemia, blood and lung samples were evaluated. RESULTS: In eMCAO set, ischemic rats showed a significant decrease in blood-peripheral lymphocytes (naive = 58.8±18.1%, ischemic = 22.9±16.4% together with an increase in polymorphonuclears (PMNs (naive = 29.2±14.7%, ischemic = 71.7±19.5%, while no change in monocytes was observed. The increase in PMNs counts was positively correlated with worse neurological outcome 48 hours after eMCAO (r = 0.55, p = 0.043. However, sham animals showed similar changes in peripheral leukocytes as those seen in ischemic rats (lymphocytes: 40.1±19.7%; PMNs: 51.7±19.2%. Analysis of bacteriological lung growth showed clear differences between naive (0±0 CFU/mL; log10 and both sham (3.9±2.5 CFU/mL; log10 and ischemic (4.3±2.9 CFU/mL; log10 groups. Additionally, naive animals presented non-pathological lung histology, while both sham and ischemic showed congestion, edema or hemorrhage. Concordant results were found in the second set of animals submitted to a tMCAO. CONCLUSIONS: Inflammatory and infection changes in Wistar rats subjected to MCAO models may be attributed not only to the brain ischemic injury but to the surgical aggression and/or anaesthetic stress. Consequently, we suggest that stroke-induced immunodepression in ischemic experimental models should be interpreted with caution

  1. Levels of detail analysis of microwave scattering from human head models for brain stroke detection

    Directory of Open Access Journals (Sweden)

    Awais Munawar Qureshi

    2017-11-01

    solvers so as to find out the solution of subject microwave scattering problem in a minimum computational time along with memory resources requirement. It is seen from this study that the microwave imaging may effectively be utilized for the detection, localization and differentiation of different types of brain stroke. The simulation results verified that the microwave imaging can be efficiently exploited to study the significant contrast between electric field values of the normal and abnormal brain tissues for the investigation of brain anomalies. In the end, a specific absorption rate analysis was carried out to compare the ionizing effects of microwave signals to different types of head model using a factor of safety for brain tissues. It is also suggested after careful study of various inversion methods in practice for microwave head imaging, that the contrast source inversion method may be more suitable and computationally efficient for such problems.

  2. GSK-3β inhibitor TWS119 attenuates rtPA-induced hemorrhagic transformation and activates the Wnt/β-catenin signaling pathway after acute ischemic stroke in rats.

    Science.gov (United States)

    Wang, Wei; Li, Mingchang; Wang, Yuefei; Li, Qian; Deng, Gang; Wan, Jieru; Yang, Qingwu; Chen, Qianxue; Wang, Jian

    2016-12-01

    Hemorrhagic transformation (HT) is a devastating complication for patients with acute ischemic stroke who are treated with tissue plasminogen activator (tPA). It is associated with high morbidity and mortality, but no effective treatments are currently available to reduce HT risk. Therefore, methods to prevent HT are urgently needed. In this study, we used TWS119, an inhibitor of glycogen synthase kinase 3β (GSK-3β), to evaluate the role of the Wnt/β-catenin signaling pathway in recombinant tPA (rtPA)-induced HT. Sprague-Dawley rats were subjected to a middle cerebral artery occlusion (MCAO) model of ischemic stroke and then were administered rtPA, rtPA combined with TWS119, or vehicle at 4 h. The animals were sacrificed 24 h after infarct induction. Rats treated with rtPA showed evident HT, had more severe neurologic deficit, brain edema, and blood-brain barrier breakdown, and had larger infarction volume than did the vehicle group. Rats treated with TWS119 had significantly improved outcomes compared with those of rats treated with rtPA alone. In addition, Western blot analysis showed that TWS119 increased the protein expression of β-catenin, claudin-3, and ZO-1 while suppressing the expression of GSK-3β. These results suggest that TWS119 reduces rtPA-induced HT and attenuates blood-brain barrier disruption, possibly through activation of the Wnt/β-catenin signaling pathway. This study provides a potential therapeutic strategy to prevent tPA-induced HT after acute ischemic stroke.

  3. Systematic Review of Parameters of Stimulation: Clinical Trial Design Characteristics and Motor Outcomes in Noninvasive Brain Stimulation in Stroke

    Directory of Open Access Journals (Sweden)

    Bamidele Oyebamiji Adeyemo

    2012-11-01

    Full Text Available Introduction: Repetitive Transcranial Magnetic Stimulation (rTMS and Transcranial Direct Current Stimulation are two powerful non-invasive neuromodulatory therapies that have the potential to alter and evaluate the integrity of the corticospinal tract. Moreover, recent evidence has shown that brain stimulation might be beneficial in stroke recovery. Therefore, investigating and investing in innovative therapies that may improve neurorehabilitative stroke recovery are next steps in research and development.Methods: This article presents an up-to-date systematic review of the treatment effects of rTMS and tDCS on motor function. A literary search was conducted, utilizing search terms stroke and transcranial stimulation. Items were excluded if they failed to: (1 include stroke patients, (2 study motor outcomes, or (3 include rTMS/tDCS as treatments. Other exclusions included: (1 reviews, editorials, and letters, (2 animal or pediatric populations, (3 case reports or sample sizes < or = 2 patients, and (4 primary outcomes of dysphagia, dysarthria, neglect, or swallowing.Results: Investigation of PubMed English Database prior to 01/01/2012 produced 695 applicable results. Studies were excluded based on the aforementioned criteria, resulting in 50 remaining studies. They included 1314 participants (1282 stroke patients and 32 healthy subjects evaluated by motor function pre- and post- tDCS or rTMS. Heterogeneity among studies’ motor assessments was high and could not be accounted for by individual comparison. Pooled effect sizes for the impact of post-treatment improvement revealed consistently demonstrable improvements after tDCS and rTMS therapeutic stimulation. Most studies provided limited follow-up for long-term effects.Conclusions: It is apparent from the available studies that noninvasive stimulation may enhance motor recovery and may lead to clinically-meaningful functional improvements in the stroke population.

  4. Patent foramen ovale closure with GORE HELEX or CARDIOFORM Septal Occluder vs. antiplatelet therapy for reduction of recurrent stroke or new brain infarct in patients with prior cryptogenic stroke: Design of the randomized Gore REDUCE Clinical Study.

    Science.gov (United States)

    Kasner, Scott E; Thomassen, Lars; Søndergaard, Lars; Rhodes, John F; Larsen, Coby C; Jacobson, Joth

    2017-12-01

    Rationale The utility of patent foramen ovale (PFO) closure for secondary prevention in patients with prior cryptogenic stroke is uncertain despite multiple randomized trials completed to date. Aims The Gore REDUCE Clinical Study (REDUCE) aims to establish superiority of patent foramen ovale closure in conjunction with antiplatelet therapy over antiplatelet therapy alone in reducing the risk of recurrent clinical ischemic stroke or new silent brain infarct in patients who have had a cryptogenic stroke. Methods and design This controlled, open-label trial randomized 664 subjects with cryptogenic stroke at 63 multinational sites in a 2:1 ratio to either antiplatelet therapy plus patent foramen ovale closure (with GORE® HELEX® Septal Occluder or GORE® CARDIOFORM Septal Occluder) or antiplatelet therapy alone. Subjects will be prospectively followed for up to five years. Neuroimaging is required for all subjects at baseline and at two years or study exit. Study outcomes The two co-primary endpoints for the study are freedom from recurrent clinical ischemic stroke through at least 24 months post-randomization and incidence of new brain infarct (defined as clinical ischemic stroke or silent brain infarct) through 24 months. The primary analyses are an unadjusted log-rank test and a binomial test of subject-based proportions, respectively, both on the intent-to-treat population, with adjustment for testing multiplicity. Discussion The REDUCE trial aims to target a patient population with truly cryptogenic strokes. Medical therapy is limited to antiplatelet agents in both arms thereby reducing confounding. The trial should determine whether patent foramen ovale closure with the Gore septal occluders is safe and more effective than medical therapy alone for the prevention of recurrent clinical ischemic stroke or new silent brain infarct; the neuroimaging data will provide an opportunity to further support the proof of concept. The main results are anticipated in 2017

  5. Changes of brain response induced by simulated weightlessness

    Science.gov (United States)

    Wei, Jinhe; Yan, Gongdong; Guan, Zhiqiang

    The characteristics change of brain response was studied during 15° head-down tilt (HDT) comparing with 45° head-up tilt (HUT). The brain responses evaluated included the EEG power spectra change at rest and during mental arithmetic, and the event-related potentials (ERPs) of somatosensory, selective attention and mental arithmetic activities. The prominent feature of brain response change during HDT revealed that the brain function was inhibited to some extent. Such inhibition included that the significant increment of "40Hz" activity during HUT arithmetic almost disappeared during HDT arithmetic, and that the positive-potential effect induced by HDT presented in all kinds of ERPs measured, but the slow negative wave reflecting mental arithmetic and memory process was elongated. These data suggest that the brain function be affected profoundly by the simulated weightlessness, therefore, the brain function change during space flight should be studied systematically.

  6. Constraint-induced movement therapy for the upper paretic limb in acute or sub-acute stroke: a systematic review.

    Science.gov (United States)

    Nijland, Rinske; Kwakkel, Gert; Bakers, Japie; van Wegen, Erwin

    2011-10-01

    Constraint-induced movement therapy is a commonly used intervention to improve upper limb function after stroke. However, the effectiveness of constraint-induced movement therapy and its optimal dosage during acute or sub-acute stroke is still under debate. To examine the literature on the effects of constraint-induced movement therapy in acute or sub-acute stroke. A literature search was performed to identify randomized, controlled trials; studies with the same outcome measure were pooled by calculating the mean difference. Separate quantitative analyses for high-intensity and low-intensity constraint-induced movement therapy were applied when possible. Five randomized, controlled trials were included, comprising 106 participants. The meta-analysis demonstrated significant mean differences in favor of constraint-induced movement therapy for the Fugl-Meyer arm, the Action Research Arm Test, the Motor Activity Log, Quality of Movement and the Grooved Pegboard Test. Nonsignificant mean difference in favor of constraint-induced movement therapy were found for the Motor Activity Log, Amount of Use. Separate analyses for high-intensity and low-intensity constraint-induced movement therapy resulted in significant favorable mean differences for low-intensity constraint-induced movement therapy for all outcome measures, in contrast to high-intensity constraint-induced movement therapy. This meta-analysis demonstrates a trend toward positive effects of high-intensity and low-intensity constraint-induced movement therapy in acute or sub-acute stroke, but also suggests that low-intensity constraint-induced movement therapy may be more beneficial during this period than high-intensity constraint-induced movement therapy. However, these results were based on a small number of studies. Therefore, more trials are needed applying different doses of therapy early after stroke and a better understanding is needed about the different time windows in which underlying mechanisms of

  7. A generative probabilistic model and discriminative extensions for brain lesion segmentation – with application to tumor and stroke

    Science.gov (United States)

    Menze, Bjoern H.; Van Leemput, Koen; Lashkari, Danial; Riklin-Raviv, Tammy; Geremia, Ezequiel; Alberts, Esther; Gruber, Philipp; Wegener, Susanne; Weber, Marc-André; Székely, Gabor; Ayache, Nicholas; Golland, Polina

    2016-01-01

    We introduce a generative probabilistic model for segmentation of brain lesions in multi-dimensional images that generalizes the EM segmenter, a common approach for modelling brain images using Gaussian mixtures and a probabilistic tissue atlas that employs expectation-maximization (EM) to estimate the label map for a new image. Our model augments the probabilistic atlas of the healthy tissues with a latent atlas of the lesion. We derive an estimation algorithm with closed-form EM update equations. The method extracts a latent atlas prior distribution and the lesion posterior distributions jointly from the image data. It delineates lesion areas individually in each channel, allowing for differences in lesion appearance across modalities, an important feature of many brain tumor imaging sequences. We also propose discriminative model extensions to map the output of the generative model to arbitrary labels with semantic and biological meaning, such as “tumor core” or “fluid-filled structure”, but without a one-to-one correspondence to the hypo-or hyper-intense lesion areas identified by the generative model. We test the approach in two image sets: the publicly available BRATS set of glioma patient scans, and multimodal brain images of patients with acute and subacute ischemic stroke. We find the generative model that has been designed for tumor lesions to generalize well to stroke images, and the generative-discriminative model to be one of the top ranking methods in the BRATS evaluation. PMID:26599702

  8. Near-infrared spectroscopy (NIRS) as a diagnostic tool in patients with suspected stroke or traumatic brain injury

    Science.gov (United States)

    Goldberg, Sonja; Lott, Carsten; Ostermeyer, M.; Hennes, Hans-Juergen

    2001-10-01

    Near-Infrared Spectroscopy (NIRS) as a diagnostic tool in patients with suspected stroke or brain injury S. Goldberg, C. Lott, M. Ostermeyer, H.-J. Hennes Absorption of Near-Infrared (NIR) light in the brain is mainly caused by hemoglobin. Superficial intracranial hematoma with a higher concentration of hemoglobin causes a higher absorption in NIRS. The existence of hemorrhage can be demonstrated by the difference of optical density, comparing identical measuring points at both hemispheres of the brain: absorption of NIR light is greater at the side of the hemorrhage, causing less reflection in NIRS. In a prospective, blinded study, 100 patients who were scheduled for CCT-scan for brain injury or symptoms of stroke have been measured by NIRS. The measurement results were proved by the CCT-diagnosis. A sensitivity of the NIR measurement of 65% and a specificity of 87% was achieved including all patients with any pathology, whereas the subgroup of 58 patients with suspected superficial hematoma and without other pathology showed pathologic findings by NIRS in all of 16 patients indicating superficial bleeding by CCT, pathology could be excluded by NIRS and CCT in 41 patients, one false positive and no false negative result. The results (sensitivity 98%, specificity 100%) support the hypothesis that NIRS is a reliable device for the detection of superficial intracranial hematoma.

  9. Effect of 3-aminobenzamide, PARP inhibitor, on matrix metalloproteinase-9 level in plasma and brain of ischemic stroke model

    International Nuclear Information System (INIS)

    Koh, Seong-Ho; Chang, Dae-Il; Kim, Hee-Tae; Kim, Juhan; Kim, Myung-Ho; Kim, Kyung Suk; Bae, Inhee; Kim, Haekwon; Kim, Dong Won; Kim, Seung Hyun

    2005-01-01

    We investigated the effect of poly(ADP-ribose) polymerase (PARP) inhibitor on the levels of plasma and brain matrix metalloproteinase-9 (MMP-9) and the expression of nuclear factor kappa B (NF-κB) during experimental focal cerebral ischemia. The 3-aminobenzamide (3-AB), a PARP inhibitor, and saline were administered to 80 Sprague-Dawley rats [3-AB group; 5 rats for plasma sampling, 35 for brain sampling, and 40 for TTC staining] and to 85 rats (10, 35, and 40, respectively), respectively, 10 min before the occlusion of the left middle cerebral artery (MCAo) for 2 h. Infarct volume was measured by TTC staining, the serial levels of plasma and brain MMP-9 were measured by zymography just before and 2, 4, 8, 24, 48, and 72 h after MCAo, brain NF-κB activity was determined by Western blotting, and neutrophil infiltration was evaluated by assessing myeloperoxidase activity. Compared with control group, the levels of plasma and brain MMP-9, brain NF-κB, and MPO activities were significantly reduced in 3-AB group at each time point (p < 0.05). Plasma MMP-9 increased maximally at 4 h and then decreased rapidly, brain MMP-9 increased maximally at 24 h and persisted until 72 h, and NF-κB increased maximally at 24 h and then decreased slowly in both groups. Therefore, the PARP inhibitor reduces the expression of MMP-9 and NF-κB and the infiltration of neutrophils in ischemic stroke

  10. Elevation of brain-enriched miRNAs in cerebrospinal fluid of patients with acute ischemic stroke

    DEFF Research Database (Denmark)

    Sorensen, Sofie Solvsten; Nygaard, Ann-Britt; Carlsen, Anting Liu

    2017-01-01

    RNA qPCR assays, and 3) validation of 24 selected miRNAs with Norgen Biotek RNA extraction protocol and Applied Biosystems qPCR assays. ResultsNGS detected 71 frequently expressed miRNAs in CSF of which brain-enriched miR-9-5p and miR-128-3p were significantly higher in CSF of stroke patients compared...... to controls. When dividing stroke patients into groups according to infarct size several brain-enriched miRNAs (miR-9-5p, miR-9-3p, miR-124-3p, and miR-128-3p) were elevated in patients with infarcts >2 cm3. This trend appeared in data from both NGS, qPCR (Exiqon), and qPCR (Applied Biosystems) but was only......BackgroundThe purpose of this study was to investigate the potential of cerebrospinal fluid miRNAs as diagnostic biomarkers of acute ischemic stroke using three different profiling techniques in order to identify and bypass any influence from technical variation. MethodsCerebrospinal fluid (CSF...

  11. Stroke: First Aid

    Science.gov (United States)

    First aid Stroke: First aid Stroke: First aid By Mayo Clinic Staff A stroke occurs when there's bleeding into your brain or when blood flow to your ... cells start dying. Seek immediate medical assistance. A stroke is a true emergency. The sooner treatment is ...

  12. Relevance of blood-brain barrier disruption after endovascular treatment of ischemic stroke: dual-energy computed tomographic study.

    Science.gov (United States)

    Renú, Arturo; Amaro, Sergio; Laredo, Carlos; Román, Luis San; Llull, Laura; Lopez, Antonio; Urra, Xabier; Blasco, Jordi; Oleaga, Laura; Chamorro, Ángel

    2015-03-01

    Computed tomographic (CT) high attenuation (HA) areas after endovascular therapy for acute ischemic stroke are a common finding indicative of blood-brain barrier disruption. Dual-energy CT allows an accurate differentiation between HA areas related to contrast staining (CS) or to brain hemorrhage (BH). We sought to evaluate the prognostic significance of the presence of CS and BH after endovascular therapy. A prospective cohort of 132 patients treated with endovascular therapy was analyzed. According to dual-energy CT findings, patients were classified into 3 groups: no HA areas (n=53), CS (n=32), and BH (n=47). The rate of new hemorrhagic transformations was recorded at follow-up neuroimaging. Clinical outcome was evaluated at 90 days with the modified Rankin Scale (poor outcome, 3-6). Poor outcome was associated with the presence of CS (odds ratio [OR], 11.3; 95% confidence interval, 3.34-38.95) and BH (OR, 10.4; 95% confidence interval, 3.42-31.68). The rate of poor outcome despite complete recanalization was also significantly higher in CS (OR, 9.7; 95% confidence interval, 2.55-37.18) and BH (OR, 15.1; 95% confidence interval, 3.85-59.35) groups, compared with the no-HA group. Patients with CS disclosed a higher incidence of delayed hemorrhagic transformation at follow-up (OR, 4.5; 95% confidence interval, 1.22-16.37) compared with no-HA patients. Blood-brain barrier disruption, defined as CS and BH on dual-energy CT, was associated with poor clinical outcomes in patients with stroke treated with endovascular therapies. Moreover, isolated CS was associated with delayed hemorrhagic transformation. These results support the clinical relevance of blood-brain barrier disruption in acute stroke. © 2015 American Heart Association, Inc.

  13. Stress-Induced Stroke and Stomach Cancer: Sex Differences in Oxygen Saturation.

    Science.gov (United States)

    Ulanova, Maria; Gekalyuk, Artem; Agranovich, Ilana; Khorovodov, Alexander; Rezunbaeva, Victoria; Borisova, Ekaterina; Sharif, Aly Esmat; Navolokin, Nikita; Shuvalova, Ekaterina; Semyachkina-Glushkovskaya, Oxana

    2016-01-01

    Sex differences in stress-related diseases such as stroke and stomach cancer are well established, but the mechanisms underlying this phenomenon remain unknown. Despite the fact that sexual hormones play an important role in the high resistance of females to harmful effects of stress compared with males, the regulation of oxygenation status can be a potential factor, which might explain sex differences in stress-induced cerebrovascular catastrophes in newborn rats and in mutagens activation in adult rats with stomach cancer.

  14. Traumatic brain injury and obesity induce persistent central insulin resistance.

    Science.gov (United States)

    Karelina, Kate; Sarac, Benjamin; Freeman, Lindsey M; Gaier, Kristopher R; Weil, Zachary M

    2016-04-01

    Traumatic brain injury (TBI)-induced impairments in cerebral energy metabolism impede tissue repair and contribute to delayed functional recovery. Moreover, the transient alteration in brain glucose utilization corresponds to a period of increased vulnerability to the negative effects of a subsequent TBI. In order to better understand the factors contributing to TBI-induced central metabolic dysfunction, we examined the effect of single and repeated TBIs on brain insulin signalling. Here we show that TBI induced acute brain insulin resistance, which resolved within 7 days following a single injury but persisted until 28 days following repeated injuries. Obesity, which causes brain insulin resistance and neuroinflammation, exacerbated the consequences of TBI. Obese mice that underwent a TBI exhibited a prolonged reduction of Akt (also known as protein kinase B) signalling, exacerbated neuroinflammation (microglial activation), learning and memory deficits, and anxiety-like behaviours. Taken together, the transient changes in brain insulin sensitivity following TBI suggest a reduced capacity of the injured brain to respond to the neuroprotective and anti-inflammatory actions of insulin and Akt signalling, and thus may be a contributing factor for the damaging neuroinflammation and long-lasting deficits that occur following TBI. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  15. Blood-brain barrier dysfunction in mice induced by lipopolysaccharide is attenuated by dapsone.

    Science.gov (United States)

    Zhou, Ting; Zhao, Lei; Zhan, Rui; He, Qihua; Tong, Yawei; Tian, Xiaosheng; Wang, Hecheng; Zhang, Tao; Fu, Yaoyun; Sun, Yang; Xu, Feng; Guo, Xiangyang; Fan, Dongsheng; Han, Hongbin; Chui, Dehua

    2014-10-24

    Blood-brain barrier (BBB) dysfunction is a key event in the development of many central nervous system (CNS) diseases, such as septic encephalopathy and stroke. 4,4'-Diaminodiphenylsulfone (DDS, Dapsone) has displayed neuroprotective effect, but whether DDS has protective role on BBB integrity is not clear. This study was designed to examine the effect of DDS on lipopolysaccharide (LPS)-induced BBB disruption and oxidative stress in brain vessels. Using in vivo multiphoton imaging, we found that DDS administration significantly restored BBB integrity compromised by LPS. DDS also increased the expression of tight junction proteins occludin, zona occludens-1 (ZO-1) and claudin-5 in brain vessels. Level of reactive oxygen species (ROS) was reduced by DDS treatment, which may due to decreased nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity and NOX2 expression. Our results showed that LPS-induced BBB dysfunction could be attenuated by DDS, indicated that DDS has a therapeutic potential for treating CNS infection and other BBB related diseases. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Effects of normobaric versus hyperbaric oxygen on cell injury induced by oxygen and glucose deprivation in acute brain slices

    Directory of Open Access Journals (Sweden)

    Laurent Chazalviel

    2016-01-01

    Full Text Available Normobaric oxygen (NBO and hyperbaric oxygen (HBO are emerging as a possible co-treatment of acute ischemic stroke. Both have been shown to reduce infarct volume, to improve neurologic outcome, to promote endogenous tissue plasminogen activator-induced thrombolysis and cerebral blood flow, and to improve tissue oxygenation through oxygen diffusion in the ischemic areas, thereby questioning the interest of HBO compared to NBO. In the present study, in order to investigate and compare the oxygen diffusion effects of NBO and HBO on acute ischemic stroke independently of their effects at the vascular level, we used acute brain slices exposed to oxygen and glucose deprivation, an ex vivo model of brain ischemia that allows investigating the acute effects of NBO (partial pressure of oxygen (pO 2 = 1 atmospheres absolute (ATA = 0.1 MPa and HBO (pO 2 = 2.5 ATA = 0.25 MPa through tissue oxygenation on ischemia-induced cell injury as measured by the release of lactate dehydrogenase. We found that HBO, but not NBO, reduced oxygen and glucose deprivation-induced cell injury, indicating that passive tissue oxygenation (i.e. without vascular support of the brain parenchyma requires oxygen partial pressure higher than 1 ATA.

  17. Automated brain computed tomographic densitometry of early ischemic changes in acute stroke

    NARCIS (Netherlands)

    Stoel, Berend C.; Marquering, Henk A.; Staring, Marius; Beenen, Ludo F.; Slump, Cornelis H.; Roos, Yvo B.; Majoie, Charles B.

    2015-01-01

    The Alberta Stroke Program Early CT score (ASPECTS) scoring method is frequently used for quantifying early ischemic changes (EICs) in patients with acute ischemic stroke in clinical studies. Varying interobserver agreement has been reported, however, with limited agreement. Therefore, our goal was

  18. Reperfusion facilitates reversible disruption of the human blood-brain barrier following acute ischaemic stroke

    International Nuclear Information System (INIS)

    Liu, Chang; Zhang, Sheng; Yan, Shenqiang; Zhang, Ruiting; Shi, Feina; Lou, Min; Ding, Xinfa; Parsons, Mark

    2018-01-01

    We aimed to detect early changes of the blood-brain barrier permeability (BBBP) in acute ischaemic stroke (AIS), with or without reperfusion, and find out whether BBBP can predict clinical outcomes. Consecutive AIS patients imaged with computed tomographic perfusion (CTP) before and 24 h after treatment were included. The relative permeability-surface area product (rPS) was calculated within the hypoperfused region (rPS hypo-i ), non-hypoperfused region of ischaemic hemisphere (rPS nonhypo-i ) and their contralateral mirror regions (rPS hypo-c and rPS nonhypo-c ). The changes of rPS were analysed using analysis of variance (ANOVA) with repeated measures. Logistic regression was used to identify independent predictors of unfavourable outcome. Fifty-six patients were included in the analysis, median age was 76 (IQR 62-81) years and 28 (50%) were female. From baseline to 24 h after treatment, rPS hypo-i , rPS nonhypo-i and rPS hypo-c all decreased significantly. The decreases in rPS hypo-i and rPS hypo-c were larger in the reperfusion group than non-reperfusion group. The rPS hypo-i at follow-up was a predictor for unfavourable outcome (OR 1.131; 95% CI 1.018-1.256; P = 0.022). Early disruption of BBB in AIS is reversible, particularly when greater reperfusion is achieved. Elevated BBBP at 24 h after treatment, not the pretreatment BBBP, predicts unfavourable outcome. (orig.)

  19. Susceptibility weighted imaging of stroke brain in response to normobaric oxygen (NBO) therapy

    Science.gov (United States)

    Zhou, Iris Y.; Igarashi, Takahiro; Guo, Yingkun; Sun, Phillip Z.

    2015-03-01

    The neuroprotective effect of oxygen leads to recent interest in normobaric oxygen (NBO) therapy after acute ischemic stroke. However, the mechanism remains unclear and inconsistent outcomes were reported in human studies. Because NBO aims to improve brain tissue oxygenation by enhancing oxygen delivery to ischemic tissue, monitoring the oxygenation level changes in response to NBO becomes necessary to elucidate the mechanism and to assess the efficacy. Susceptibility weighted imaging (SWI) which provides a new MRI contrast by combining the magnitude and phase images is fit for purpose. SWI is sensitive to deoxyhemoglobin level changes and thus can be used to evaluate the cerebral metabolic rate of oxygen. In this study, SWI was used for in vivo monitoring of oxygenation changes in a rat model of permanent middle cerebral artery occlusion (MCAO) before, during and after 30 min of NBO treatment. Regions of interest in ischemic core, penumbra and contralateral normal area were generated based on diffusionweighted imaging and perfusion imaging. Significant differences in SWI indicating different oxygenation levels were generally found: contralateral normal > penumbra > ischemic core. Ischemic core showed insignificant increase in oxygenation during NBO and returned to pre-treatment level after termination of NBO. Meanwhile, the oxygenation levels slightly increased in contralateral normal and penumbra regions during NBO and significantly decreased to a level lower than pre-treatment after termination of NBO, indicating secondary metabolic disruption upon the termination of transient metabolic support from oxygen. Further investigation of NBO effect combined with reperfusion is necessary while SWI can be used to detect hemorrhagic transformation after reperfusion.

  20. D-galactose-induced brain ageing model

    DEFF Research Database (Denmark)

    Sadigh-Eteghad, Saeed; Majdi, Alireza; McCann, Sarah K.

    2017-01-01

    Animal models are commonly used in brain ageing research. Amongst these, models where rodents are exposed to d-galactose are held to recapitulate a number of features of ageing including neurobehavioral and neurochemical changes. However, results from animal studies are often inconsistent...

  1. RESVERATROL PRECONDITIONING INDUCES A NOVEL EXTENDED WINDOW OF ISCHEMIC TOLERANCE IN THE MOUSE BRAIN

    Science.gov (United States)

    Koronowski, Kevin B.; Dave, Kunjan R.; Saul, Isabel; Camarena, Vladimir; Thompson, John W.; Neumann, Jake T.; Young, Juan I.; Perez-Pinzon, Miguel A.

    2015-01-01

    Background and Purpose Prophylactic treatments that afford neuroprotection against stroke may emerge from the field of preconditioning. Resveratrol mimics ischemic preconditioning, reducing ischemic brain injury when administered two days prior to global ischemia in rats. This protection is linked to Sirt1 and enhanced mitochondrial function possibly through its repression of UCP2. BDNF is another neuroprotective protein associated with Sirt1. In this study we sought to identify the conditions of resveratrol preconditioning (RPC) that most robustly induce neuroprotection against focal ischemia in mice. Methods We tested four different RPC paradigms against a middle cerebral artery occlusion (MCAo) model of stroke. Infarct volume and neurological score were calculated 24 hours following MCAo. Sirt1-chromatin binding was evaluated by ChIP-qPCR. Percoll gradients were used to isolate synaptic fractions and changes in protein expression were determined via Western blot analysis. BDNF concentration was measured using a BDNF-specific ELISA assay. Results While repetitive RPC induced neuroprotection from MCAo, strikingly one application of RPC 14 days prior to MCAo showed the most robust protection, reducing infarct volume by 33% and improving neurological score by 28%. Fourteen days following RPC, Sirt1 protein was increased 1.5 fold and differentially bound to the UCP2 and BDNF promoter regions. Accordingly, synaptic UCP2 protein decreased by 23% and cortical BDNF concentration increased 26%. Conclusions RPC induces a novel extended window of ischemic tolerance in the brain that lasts for at least 14 days. Our data suggest that this tolerance may be mediated by Sirt1, through upregulation of BDNF and downregulation of UCP2. PMID:26159789

  2. Amelioration of cold injury-induced cortical brain edema formation by selective endothelin ETB receptor antagonists in mice.

    Science.gov (United States)

    Michinaga, Shotaro; Nagase, Marina; Matsuyama, Emi; Yamanaka, Daisuke; Seno, Naoki; Fuka, Mayu; Yamamoto, Yui; Koyama, Yutaka

    2014-01-01

    Brain edema is a potentially fatal pathological condition that often occurs in stroke and head trauma. Following brain insults, endothelins (ETs) are increased and promote several pathophysiological responses. This study examined the effects of ETB antagonists on brain edema formation and disruption of the blood-brain barrier in a mouse cold injury model (Five- to six-week-old male ddY mice). Cold injury increased the water content of the injured cerebrum, and promoted extravasation of both Evans blue and endogenous albumin. In the injury area, expression of prepro-ET-1 mRNA and ET-1 peptide increased. Intracerebroventricular (ICV) administration of BQ788 (ETB antagonist), IRL-2500 (ETB antagonist), or FR139317 (ETA antagonist) prior to cold injury significantly attenuated the increase in brain water content. Bolus administration of BQ788, IRL-2500, or FR139317 also inhibited the cold injury-induced extravasation of Evans blue and albumin. Repeated administration of BQ788 and IRL-2500 beginning at 24 h after cold injury attenuated both the increase in brain water content and extravasation of markers. In contrast, FR139317 had no effect on edema formation when administrated after cold injury. Cold injury stimulated induction of glial fibrillary acidic protein-positive reactive astrocytes in the injured cerebrum. Induction of reactive astrocytes after cold injury was attenuated by ICV administration of BQ788 or IRL-2500. These results suggest that ETB receptor antagonists may be an effective approach to ameliorate brain edema formation following brain insults.

  3. Inhibitory non-invasive brain stimulation to homologous language regions as an adjunct to speech and language therapy in post-stroke aphasia: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Begonya eOtal

    2015-04-01

    Full Text Available Chronic communication impairment is common after stroke, and conventional speech and language therapy (SLT strategies have limited effectiveness in post-stroke aphasia. Neurorehabilitation with non-invasive brain stimulation techniques (NIBS ‒ particularly repetitive transcranial magnetic stimulation (rTMS or transcranial direct current stimulation (tDCS ‒ may enhance the effects of SLT in selected patients. Applying inhibitory NIBS to specific homologous language regions may induce neural reorganization and reduce interhemispheric competition. This mini review highlights randomized controlled trials (RCTs and randomized cross-over trials using low-frequency rTMS or cathodal tDCS over the non-lesioned non-language dominant hemisphere and performs an exploratory meta-analysis of those trials considered combinable. Using a random-effects model, a meta-analysis of nine eligible trials involving 215 participants showed a significant mean effect size of 0.51 (95% CI = 0.24 to 0.79 for the main outcome accuracy of naming in language assessment. No heterogeneity was observed (I2 = 0%. More multicenter RCTs with larger populations and homogenous intervention protocols are required to confirm these and the longer-term effects.

  4. Combined rTMS and virtual reality brain-computer interface training for motor recovery after stroke

    Science.gov (United States)

    Johnson, N. N.; Carey, J.; Edelman, B. J.; Doud, A.; Grande, A.; Lakshminarayan, K.; He, B.

    2018-02-01

    Objective. Combining repetitive transcranial magnetic stimulation (rTMS) with brain-computer interface (BCI) training can address motor impairment after stroke by down-regulating exaggerated inhibition from the contralesional hemisphere and encouraging ipsilesional activation. The objective was to evaluate the efficacy of combined rTMS  +  BCI, compared to sham rTMS  +  BCI, on motor recovery after stroke in subjects with lasting motor paresis. Approach. Three stroke subjects approximately one year post-stroke participated in three weeks of combined rTMS (real or sham) and BCI, followed by three weeks of BCI alone. Behavioral and electrophysiological differences were evaluated at baseline, after three weeks, and after six weeks of treatment. Main results. Motor improvements were observed in both real rTMS  +  BCI and sham groups, but only the former showed significant alterations in inter-hemispheric inhibition in the desired direction and increased relative ipsilesional cortical activation from fMRI. In addition, significant improvements in BCI performance over time and adequate control of the virtual reality BCI paradigm were observed only in the former group. Significance. When combined, the results highlight the feasibility and efficacy of combined rTMS  +  BCI for motor recovery, demonstrated by increased ipsilesional motor activity and improvements in behavioral function for the real rTMS  +  BCI condition in particular. Our findings also demonstrate the utility of BCI training alone, as shown by behavioral improvements for the sham rTMS  +  BCI condition. This study is the first to evaluate combined rTMS and BCI training for motor rehabilitation and provides a foundation for continued work to evaluate the potential of both rTMS and virtual reality BCI training for motor recovery after stroke.

  5. Combined rTMS and virtual reality brain-computer interface training for motor recovery after stroke.

    Science.gov (United States)

    Johnson, N N; Carey, J; Edelman, B J; Doud, A; Grande, A; Lakshminarayan, K; He, B

    2018-02-01

    Combining repetitive transcranial magnetic stimulation (rTMS) with brain-computer interface (BCI) training can address motor impairment after stroke by down-regulating exaggerated inhibition from the contralesional hemisphere and encouraging ipsilesional activation. The objective was to evaluate the efficacy of combined rTMS  +  BCI, compared to sham rTMS  +  BCI, on motor recovery after stroke in subjects with lasting motor paresis. Three stroke subjects approximately one year post-stroke participated in three weeks of combined rTMS (real or sham) and BCI, followed by three weeks of BCI alone. Behavioral and electrophysiological differences were evaluated at baseline, after three weeks, and after six weeks of treatment. Motor improvements were observed in both real rTMS  +  BCI and sham groups, but only the former showed significant alterations in inter-hemispheric inhibition in the desired direction and increased relative ipsilesional cortical activation from fMRI. In addition, significant improvements in BCI performance over time and adequate control of the virtual reality BCI paradigm were observed only in the former group. When combined, the results highlight the feasibility and efficacy of combined rTMS  +  BCI for motor recovery, demonstrated by increased ipsilesional motor activity and improvements in behavioral function for the real rTMS  +  BCI condition in particular. Our findings also demonstrate the utility of BCI training alone, as shown by behavioral improvements for the sham rTMS  +  BCI condition. This study is the first to evaluate combined rTMS and BCI training for motor rehabilitation and provides a foundation for continued work to evaluate the potential of both rTMS and virtual reality BCI training for motor recovery after stroke.

  6. Glutamate excitoxicity is the key molecular mechanism which is influenced by body temperature during the acute phase of brain stroke.

    Science.gov (United States)

    Campos, Francisco; Pérez-Mato, María; Agulla, Jesús; Blanco, Miguel; Barral, David; Almeida, Angeles; Brea, David; Waeber, Christian; Castillo, José; Ramos-Cabrer, Pedro

    2012-01-01

    Glutamate excitotoxicity, metabolic rate and inflammatory response have been associated to the deleterious effects of temperature during the acute phase of stroke. So far, the association of temperature with these mechanisms has been studied individually. However, the simultaneous study of the influence of temperature on these mechanisms is necessary to clarify their contributions to temperature-mediated ischemic damage. We used non-invasive Magnetic Resonance Spectroscopy to simultaneously measure temperature, glutamate excitotoxicity and metabolic rate in the brain in animal models of ischemia. The immune response to ischemia was measured through molecular serum markers in peripheral blood. We submitted groups of animals to different experimental conditions (hypothermia at 33°C, normothermia at 37°C and hyperthermia at 39°C), and combined these conditions with pharmacological modulation of glutamate levels in the brain through systemic injections of glutamate and oxaloacetate. We show that pharmacological modulation of glutamate levels can neutralize the deleterious effects of hyperthermia and the beneficial effects of hypothermia, however the analysis of the inflammatory response and metabolic rate, demonstrated that their effects on ischemic damage are less critical than glutamate excitotoxity. We conclude that glutamate excitotoxicity is the key molecular mechanism which is influenced by body temperature during the acute phase of brain stroke.

  7. Predictors and brain connectivity changes associated with arm motor function improvement from intensive practice in chronic stroke [version 2; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    George F. Wittenberg

    2017-02-01

    Full Text Available Background and Purpose: The brain changes that underlie therapy-induced improvement in motor function after stroke remain obscure. This study sought to demonstrate the feasibility and utility of measuring motor system physiology in a clinical trial of intensive upper extremity rehabilitation in chronic stroke-related hemiparesis. Methods: This was a substudy of two multi-center clinical trials of intensive robotic and intensive conventional therapy arm therapy in chronic, significantly hemiparetic, stroke patients. Transcranial magnetic stimulation was used to measure motor cortical output to the biceps and extensor digitorum communus muscles. Magnetic resonance imaging (MRI was used to determine the cortical anatomy, as well as to measure fractional anisotropy, and blood oxygenation (BOLD during an eyes-closed rest state. Region-of-interest time-series correlation analysis was performed on the BOLD signal to determine interregional connectivity. Functional status was measured with the upper extremity Fugl-Meyer and Wolf Motor Function Test. Results: Motor evoked potential (MEP presence was associated with better functional outcomes, but the effect was not significant when considering baseline impairment. Affected side internal capsule fractional anisotropy was associated with better function at baseline. Affected side primary motor cortex (M1 activity became more correlated with other frontal motor regions after treatment. Resting state connectivity between affected hemisphere M1 and dorsal premotor area (PMAd predicted recovery. Conclusions: Presence of motor evoked potentials in the affected motor cortex and its functional connectivity with PMAd may be useful in predicting recovery. Functional connectivity in the motor network shows a trends towards increasing after intensive robotic or non-robotic arm therapy. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00372411 \\& NCT00333983.

  8. Magnetic inductive phase shift: a new method to differentiate hemorrhagic stroke from ischemic stroke on rabbit.

    Science.gov (United States)

    Yan, Qingguang; Jin, Gui; Ma, Ke; Qin, Mingxin; Zhuang, Wei; Sun, Jian

    2017-05-30

    The major therapy for ischemic stroke is thrombolytic treatment, but severe consequences occur when this method is used to treat hemorrhagic stroke. Currently, computed tomography and magnetic resonance imaging are used to differentiate between two types of stroke, but these two methods are ineffective for pre-hospital care. We developed a new brain diagnostic device for rabbits based on electromagnetic induction to non-invasively differentiate two types of stroke. The device includes two coils and a phase difference measurement system that detects the magnetic inductive phase shift (MIPS) value to reflect the tissue's condition. The hemorrhage model was established through the injection of autologous blood into the internal capsule of a rabbit's brain. Ischemia was induced in the brain of a rabbit by bilateral carotid artery occlusion. Two types of animal models were measured with our device. The MIPS value gradually decreased with increasing injected blood and increased with ischemia time. The MIPS changes induced by the two types of strokes were exact opposites, and the absolute values of MIPS variation in the hemorrhagic and the ischemic groups were significantly larger than those of the normal control group (P stroke from hemorrhagic stroke on rabbit brain in a non-invasive, continuous, and bulk monitoring manner by using a simple and inexpensive apparatus.

  9. Mini-Stroke vs. Regular Stroke: What's the Difference?

    Science.gov (United States)

    ... How is a ministroke different from a regular stroke? Answers from Jerry W. Swanson, M.D. When ... brain, spinal cord or retina, which may cause stroke-like symptoms but does not damage brain cells ...

  10. Stroke (For Kids)

    Science.gov (United States)

    ... your friend. Being around friends can help with healing. Preventing Strokes Some strokes can be prevented in ... Why Does Hair Turn Gray? What Are Wrinkles? Alzheimer Disease Your Brain & Nervous System Why Exercise Is ...

  11. Laser-induced breakdown ignition in a gas fed two-stroke engine

    Science.gov (United States)

    Loktionov, E. Y.; Pasechnikov, N. A.; Telekh, V. D.

    2018-01-01

    Laser-induced ignition for internal combustion engines is investigated intensively after demonstration of a compact ‘laser plug’ possibility. Laser spark benefits as compared to traditional spark plugs are higher compression rate, and possibility of almost any fuel ignition, so lean mixtures burning with lower temperatures could reduce harmful exhausts (NO x , CH, etc). No need in electrode and possibility for multi-point, linear or circular ignition can make combustion even more effective. Laser induced combustion wave appears faster and is more stable in time, than electric one, so can be used for ramjets, chemical thrusters, and gas turbines. To the best of our knowledge, we have performed laser spark ignition of a gas fed two-stroke engine for the first time. Combustion temperature and pressure, exhaust composition, ignition timing were investigated at laser and compared to a regular electric spark ignition in a two-stroke model engine. Presented results show possibility for improvement of two-stroke engines performance, in terms of rotation rate increase and NO x emission reduction. Such compact engines using locally mined fuel could be highly demanded in remote Arctic areas.

  12. Cathepsin D deficiency induces oxidative damage in brain pericytes and impairs the blood-brain barrier.

    Science.gov (United States)

    Okada, Ryo; Wu, Zhou; Zhu, Aiqin; Ni, Junjun; Zhang, Jingqi; Yoshimine, Yoshito; Peters, Christoph; Saftig, Paul; Nakanishi, Hiroshi

    2015-01-01

    Recent evidence suggests that peripheral blood mononuclear cells (PBMCs) contribute to the pathogenesis of neuropathological changes in patients with neuronal ceroid lipofuscinosis (NCL) and lysosomal storage diseases. In order to examine the possible increase in the permeability of the blood-brain-barrier (BBB) and resultant infiltration of PBMCs due to cathepsin D (CatD) deficiency, a process underlying the onset of congenital NCL, we examined structural changes in brain vessels in CatD-/- mice. Consequently, the mean diameter of the brain vessels in the cerebral cortex on postnatal day 24 (P24) was significantly larger in CatD-/- mice than in wild-type mice. Furthermore, the mean number of brain pericytes in CatD-/- mice began to decline significantly on P16 and almost disappeared on P24, and oxidative DNA damage was first detected in brain pericytes on P12. Examinations with electron microscopy revealed that brain pericytes were laden with dense granular bodies, cytoplasmic vacuoles and lipid droplets. The infiltration of PBMCs characterized by segmented nucleus laden with dense granular bodies was also noted in the cerebral cortex of CatD-/- mice. When primary cultured microglia prepared from enhanced green fluorescent protein (GFP)-expressing transgenic rats were injected into the common carotid artery, GFP-positive microglia were detected in the brain parenchyma of CatD-/-, but not wild-type, mice. Moreover, pepstatin A, a specific aspartic protease inhibitor, induced mitochondria-derived reactive oxygen species (ROS) production in the isolated brain pericytes, which decreased the cell viability. These observations suggest that increased lysosomal storage due to CatD deficiency causes oxidative damage in brain pericytes, subsequently resulting in an increased vessel diameter, enhanced permeability of the BBB and the infiltration of PBMCs. Therefore, protecting brain pericytes against lysosomal storage-induced oxidative stress may represent an alternative

  13. In vivo evidence of methamphetamine induced attenuation of brain tissue oxygenation as measured by EPR oximetry

    International Nuclear Information System (INIS)

    Weaver, John; Yang, Yirong; Purvis, Rebecca; Weatherwax, Theodore; Rosen, Gerald M.; Liu, Ke Jian

    2014-01-01

    Abuse of methamphetamine (METH) is a major and significant societal problem in the US, as a number of studies have suggested that METH is associated with increased cerebrovascular events, hemorrhage or vasospasm. Although cellular and molecular mechanisms involved in METH-induced toxicity are not completely understood, changes in brain O 2 may play an important role and contribute to METH-induced neurotoxicity including dopaminergic receptor degradation. Given that O 2 is the terminal electron acceptor for many enzymes that are important in brain function, the impact of METH on brain tissue pO 2 in vivo remains largely uncharacterized. This study investigated striatal tissue pO 2 changes in male C57BL/6 mice (16–20 g) following METH administration using EPR oximetry, a highly sensitive modality to measure pO 2 in vivo, in situ and in real time. We demonstrate that 20 min after a single injection of METH (8 mg/kg i.v.), the striatal pO 2 was reduced to 81% of the pretreatment level and exposure to METH for 3 consecutive days further attenuated striatal pO 2 to 64%. More importantly, pO 2 did not recover fully to control levels even 24 h after administration of a single dose of METH and continual exposure to METH exacerbates the condition. We also show a reduction in cerebral blood flow associated with a decreased brain pO 2 indicating an ischemic condition. Our findings suggests that administration of METH can attenuate brain tissue pO 2 , which may lead to hypoxic insult, thus a risk factor for METH-induced brain injury and the development of stroke in young adults. - Highlights: • Explored striatal tissue pO 2 in vivo after METH administration by EPR oximetry. • pO 2 was reduced by 81% after a single dose and 64% after 3 consecutive daily doses. • pO 2 did not recover fully to control levels even 24 h after a single dose. • Decrease in brain tissue pO 2 may be associated with a decrease in CBF. • Administration of methamphetamine may lead to hypoxic

  14. In vivo evidence of methamphetamine induced attenuation of brain tissue oxygenation as measured by EPR oximetry

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, John, E-mail: jmweaver@salud.unm.edu [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Yang, Yirong [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Purvis, Rebecca [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Weatherwax, Theodore [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Rosen, Gerald M. [Center for Biomedical Engineering and Technology, University of Maryland, Baltimore, MD 21201 (United States); Center for EPR Imaging In Vivo Physiology, University of Maryland, Baltimore, MD 21201 (United States); Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201 (United States); Liu, Ke Jian [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States)

    2014-03-01

    Abuse of methamphetamine (METH) is a major and significant societal problem in the US, as a number of studies have suggested that METH is associated with increased cerebrovascular events, hemorrhage or vasospasm. Although cellular and molecular mechanisms involved in METH-induced toxicity are not completely understood, changes in brain O{sub 2} may play an important role and contribute to METH-induced neurotoxicity including dopaminergic receptor degradation. Given that O{sub 2} is the terminal electron acceptor for many enzymes that are important in brain function, the impact of METH on brain tissue pO{sub 2}in vivo remains largely uncharacterized. This study investigated striatal tissue pO{sub 2} changes in male C57BL/6 mice (16–20 g) following METH administration using EPR oximetry, a highly sensitive modality to measure pO{sub 2}in vivo, in situ and in real time. We demonstrate that 20 min after a single injection of METH (8 mg/kg i.v.), the striatal pO{sub 2} was reduced to 81% of the pretreatment level and exposure to METH for 3 consecutive days further attenuated striatal pO{sub 2} to 64%. More importantly, pO{sub 2} did not recover fully to control levels even 24 h after administration of a single dose of METH and continual exposure to METH exacerbates the condition. We also show a reduction in cerebral blood flow associated with a decreased brain pO{sub 2} indicating an ischemic condition. Our findings suggests that administration of METH can attenuate brain tissue pO{sub 2}, which may lead to hypoxic insult, thus a risk factor for METH-induced brain injury and the development of stroke in young adults. - Highlights: • Explored striatal tissue pO{sub 2}in vivo after METH administration by EPR oximetry. • pO{sub 2} was reduced by 81% after a single dose and 64% after 3 consecutive daily doses. • pO{sub 2} did not recover fully to control levels even 24 h after a single dose. • Decrease in brain tissue pO{sub 2} may be associated with a decrease in

  15. Integrated Technologies Like Noninvasive Brain Stimulation (NIBS for Stroke Rehabilitation; New Hopes for Patients, Neuroscientists, and Clinicians in Iran

    Directory of Open Access Journals (Sweden)

    Shahid Bashir

    2010-08-01

    Full Text Available A B S T R A C TThe applications of neurophysiological therapy techniques range far and few in the realm of modern day medicine. However, the concept of electromagnetic stimulation, the basis for many noninvasive brain stimulation (NIBS techniques today, has been of interest to the scientific community since the late nineteenth century. Recently, transcranial direct current stimulation (tDCS and transcranial magnetic stimulation (TMS, two noninvasive neurostimulation techniques, have begun to gain popularity and acceptance in the clinical neurophysiology, neurorehabilitaion, neurology, neuroscience, and psychiatry has spread widely, mostly in research applications, but increasingly with clinical aims in mind. These two neurophysiological techniques have proven to be valuable assets in not only the diagnosis, but also the treatment of many neurological disorders (post-stroke motor deficits, tinnitus, fibromyalgia, depression, epilepsy, autism, ageing and parkinson’s disease. Its effects can be modulated by combination with pharmacological treatment that has undergone resurgence in recent years. In this review we discuss how these integrated technology like NIBS for evaluation in the clinical evidence to date and what mechanism it work for stroke rehabilitation particularly. Then, we will review the current situation of stroke rehabilitation in Iran and new hopes that NIBS could bring for clinicians and patients in this nationally prioritized field.

  16. Changes in functional connectivity correlate with behavioral gains in stroke patients after therapy using a brain-computer interface device

    Directory of Open Access Journals (Sweden)

    Brittany Mei Young

    2014-07-01

    Full Text Available Brain-computer interface (BCI technology is being incorporated into new stroke rehabilitation devices, but little is known about brain changes associated with its use. We collected anatomical and functional MRI of 9 stroke patients with persistent upper extremity motor impairment before, during, and after therapy using a BCI system. Subjects were asked to perform finger tapping of the impaired hand during fMRI. Action Research Arm Test (ARAT, 9-Hole Peg Test (9-HPT, and Stroke Impact Scale (SIS domains of Hand Function (HF and Activities of Daily Living (ADL were also assessed. Group-level analyses examined changes in whole-brain task-based functional connectivity (FC to seed regions in the motor network observed during and after BCI therapy. Whole-brain FC analyses seeded in each thalamus showed FC increases from baseline at mid-therapy and post-therapy (p< 0.05. Changes in FC between seeds at both the network and the connection levels were examined for correlations with changes in behavioral measures. Average motor network FC was increased post-therapy, and changes in average network FC correlated (p < 0.05 with changes in performance on ARAT (R2=0.21, 9-HPT (R2=0.41, SIS HF (R2=0.27, and SIS ADL (R2=0.40. Multiple individual connections within the motor network were found to correlate in change from baseline with changes in behavioral measures. Many of these connections involved the thalamus, with change in each of four behavioral measures significantly correlating with change from baseline FC of at least one thalamic connection. These preliminary results show changes in FC that occur with the administration of rehabilitative therapy using a BCI system. The correlations noted between changes in FC measures and changes in behavioral outcomes indicate that both adaptive and maladaptive changes in FC may develop with this therapy and also suggest a brain-behavior relationship that may be stimulated by the neuromodulatory component of BCI therapy.

  17. Brain mapping for long-term recovery of gait after supratentorial stroke: A retrospective cross-sectional study.

    Science.gov (United States)

    Kim, Dae Hyun; Kyeong, Sunghyon; Do, Kyung Hee; Lim, Seong Kyu; Cho, Hyong Keun; Jung, Suk; Kim, Hye Won

    2018-04-01

    The recovery of independent gait after stroke is a main goal of patients and understanding the relationship between brain lesions and the recovery of gait can help physicians set viable rehabilitation plans. Our study investigated the association between variables of gait parameters and brain lesions.Fifty poststroke patients with a mean age of 67.5 ± 1.3 years and an average duration after onset of 62.2 ± 7.9 months were included. Three-dimensional gait analysis and magnetic resonance imaging were conducted for all patients. Twelve quantified gait parameters of temporal-spatial, kinematic, and kinetic data were used. To correlate gait parameters with specific brain lesions, we used a voxel-based lesion symptom mapping analysis. Statistical significance was set to an uncorrected P value 10 voxels.Based on the location of a brain lesion, the following results were obtained: The posterior limb of the internal capsule was significantly associated with gait speed and increased knee extension in the stance phase. The hippocampus and frontal lobe were significantly associated with cadence. The proximal corona radiata was significantly associated with stride length and affected the hip maximal extension angle in the stance phase. The paracentral lobule was significantly associated with the affected knee maximal flexion angle in the swing phase and with the affected ankle maximal dorsiflexion angle in the stance phase. The frontal lobe, thalamus, and the lentiform nucleus were associated with kinetic gait parameters.Cortical, proximal white matter, and learning-related and motor-related areas are mainly associated with one's walking ability after stroke.

  18. MRI-induced heating of deep brain stimulation leads

    International Nuclear Information System (INIS)

    Mohsin, Syed A; Sheikh, Noor M; Saeed, Usman

    2008-01-01

    The radiofrequency (RF) field used in magnetic resonance imaging is scattered by medical implants. The scattered field of a deep brain stimulation lead can be very intense near the electrodes stimulating the brain. The effect is more pronounced if the lead behaves as a resonant antenna. In this paper, we examine the resonant length effect. We also use the finite element method to compute the near field for (i) the lead immersed in inhomogeneous tissue (fat, muscle, and brain tissues) and (ii) the lead connected to an implantable pulse generator. Electric field, specific absorption rate and induced temperature rise distributions have been obtained in the brain tissue surrounding the electrodes. The worst-case scenario has been evaluated by neglecting the effect of blood perfusion. The computed values are in good agreement with in vitro measurements made in the laboratory.

  19. Patterns of Post-Stroke Brain Damage that Predict Speech Production Errors in Apraxia of Speech and Aphasia Dissociate

    Science.gov (United States)

    Basilakos, Alexandra; Rorden, Chris; Bonilha, Leonardo; Moser, Dana; Fridriksson, Julius

    2015-01-01

    Background and Purpose Acquired apraxia of speech (AOS) is a motor speech disorder caused by brain damage. AOS often co-occurs with aphasia, a language disorder in which patients may also demonstrate speech production errors. The overlap of speech production deficits in both disorders has raised questions regarding if AOS emerges from a unique pattern of brain damage or as a sub-element of the aphasic syndrome. The purpose of this study was to determine whether speech production errors in AOS and aphasia are associated with distinctive patterns of brain injury. Methods Forty-three patients with history of a single left-hemisphere stroke underwent comprehensive speech and language testing. The Apraxia of Speech Rating Scale was used to rate speech errors specific to AOS versus speech errors that can also be associated with AOS and/or aphasia. Localized brain damage was identified using structural MRI, and voxel-based lesion-impairment mapping was used to evaluate the relationship between speech errors specific to AOS, those that can occur in AOS and/or aphasia, and brain damage. Results The pattern of brain damage associated with AOS was most strongly associated with damage to cortical motor regions, with additional involvement of somatosensory areas. Speech production deficits that could be attributed to AOS and/or aphasia were associated with damage to the temporal lobe and the inferior pre-central frontal regions. Conclusion AOS likely occurs in conjunction with aphasia due to the proximity of the brain areas supporting speech and language, but the neurobiological substrate for each disorder differs. PMID:25908457

  20. N-Myc Downstream-Regulated Gene 2 (Ndrg2) Is Involved in Ischemia-Hypoxia-Induced Astrocyte Apoptosis: a Novel Target for Stroke Therapy.

    Science.gov (United States)

    Ma, Yu-Long; Zhang, Li-Xia; Liu, Guang-Lin; Fan, Yanhong; Peng, Ye; Hou, Wu-Gang

    2017-07-01

    Nearly all clinical trials that have attempted to develop effective strategies against ischemic stroke have failed, excluding those for thrombolysis, and most of these trials focused only on preventing neuronal loss. However, astrocytes have gradually become a target for neuroprotection in stroke. In previous studies, we showed that the newly identified molecular N-myc downstream-regulated gene 2 (Ndrg2) is specifically expressed in astrocytes in the brain and involved in some neurodegenerative diseases. However, the role of NDRG2 in ischemic stroke remained unclear. In this study, we investigated the role of NDRG2 in middle cerebral artery occlusion (MCAO)-induced focal cerebral ischemia and in oxygen-glucose deprivation (OGD)-induced cellular apoptosis in the M1800 astrocyte cell line. NDRG2 mRNA and protein expression began to increase at 6 and 2 h after reperfusion and peaked at 24 h in the ischemic penumbra and in M1800 cells, as detected by RT-PCR and Western blotting. Double immunofluorescence staining showed that the number of apoptotic cells increased as the NDRG2-positive signal increased and that the NDRG2 signal was sometimes co-localized with TUNEL-positive cells and translocated from the cytoplasm to the nucleus in both the ischemic penumbra and the M1800 cells. Using a lentivirus, we successfully constructed two stable astrocytic cell lines in which NDRG2 expression was significantly up- or down-regulated. NDRG2 silencing had a proliferative effect and reduced the percentage of apoptotic cells, reactive oxygen species (ROS) production, and cleaved Caspase-3 protein expression following OGD, whereas NDRG2 over-expression had the opposite effects. In conclusion, NDRG2 is involved in astrocyte apoptosis following ischemic-hypoxic injury, and inhibiting NDRG2 expression significantly reduces ROS production and astrocyte apoptosis. These findings provide insight into the role of NDRG2 in ischemic-hypoxic injury and provide potential targets for future

  1. Identification of pro-angiogenic markers in blood vessels from stroked-affected brain tissue using laser-capture microdissection

    Directory of Open Access Journals (Sweden)

    Baldellou Maribel

    2009-03-01

    Full Text Available Abstract Background Angiogenesis correlates with patient survival following acute ischaemic stroke, and survival of neurons is greatest in tissue undergoing angiogenesis. Angiogenesis is critical for the development of new microvessels and leads to re-formation of collateral circulation, reperfusion, enhanced neuronal survival and improved recovery. Results Here, we have isolated active (CD105/Flt-1 positive and inactive (CD105/Flt-1 minus (n=5 micro-vessel rich-regions from stroke-affected and contralateral tissue of patients using laser-capture micro-dissection. Areas were compared for pro- and anti-angiogenic gene expression using targeted TaqMan microfluidity cards containing 46 genes and real-time PCR. Further analysis of key gene de-regulation was performed by immunohistochemistry to define localization and expression patterns of identified markers and de novo synthesis by human brain microvessel endothelial cells (HBMEC was examined following oxygen-glucose deprivation (OGD. Our data revealed that seven pro-angiogenic genes were notably up-regulated in CD105 positive microvessel rich regions. These were, beta-catenin, neural cell adhesion molecule (NRCAM, matrix metalloproteinase-2 (MMP-2, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1, hepatocyte growth factor-alpha (HGF-alpha, monocyte chemottractant protein-1 (MCP-1 and and Tie-2 as well as c-kit. Immunohistochemistry demonstrated strong staining of MMP-2, HGF-alpha, MCP-1 and Tie-2 in stroke-associated regions of active remodeling in association with CD105 positive staining. In vitro, OGD stimulated production of Tie-2, MCP-1 and MMP-2 in HBMEC, demonstrated a de novo response to hypoxia. Conclusion In this work we have identified concurrent activation of key angiogenic molecules associated with endothelial cell migration, differentiation and tube-formation, vessel stabilization and stem cell homing mechanisms in areas of revascularization. Therapeutic stimulation of these

  2. Modulation of Brain Dead Induced Inflammation by Vagus Nerve Stimulation

    NARCIS (Netherlands)

    Hoeger, S.; Bergstraesser, C.; Selhorst, J.; Fontana, J.; Birck, R.; Waldherr, R.; Beck, G.; Sticht, C.; Seelen, M. A.; van Son, W. J.; Leuvenink, H.; Ploeg, R.; Schnuelle, P.; Yard, B. A.

    Because the vagus nerve is implicated in control of inflammation, we investigated if brain death (BD) causes impairment of the parasympathetic nervous system, thereby contributing to inflammation. BD was induced in rats. Anaesthetised ventilated rats (NBD) served as control. Heart rate variability

  3. Hemodynamic and metabolic state of hyperfixation with 99mTc-HMPAO brain SPECT in subacute stroke

    International Nuclear Information System (INIS)

    Cho, Ihnho; Hayashida, Kohei; Imakita, Satoshi; Kume, Norihiko; Fukuchi, Kazuki

    2000-01-01

    By means of positron emission tomography (PET), we investigated the hemodynamic and metabolic state of the hyperfixation identified as the increased accumulation with 99m Tc-d, l-hexamethylpropyleneamine oxime (HMPAO) by single photon emission computed tomography (SPECT) in patients with subacute stroke. We studied four patients with subacute stroke having hyperfixed areas evaluated with CBF, CMRO 2 , OEF and CBV by PET. The hyperfixation rate with 99m Tc-HMPAO was obtained by comparing the surplus rate with standardized CBF. The OEF and CMRO 2 values in the hyperfixed areas of 4 patients were significantly lower than those in normal 5 controls (p 99m Tc-HMPAO in the infarct area revealing a mismatch between CMRO 2 and CBF meant relative luxury perfusion. The hyperfixation rate determined by 99m Tc-HMPAO brain SPECT correlated with CBV in the PET study. We can conclude that one of the main factors which caused hyperfixation was vasodilatation as well as the blood brain barrier disruption and the neovascularization. (author)

  4. Antigen-specific immune reactions to ischemic stroke

    Directory of Open Access Journals (Sweden)

    Xabier eUrra

    2014-09-01

    Full Text Available Brain proteins are detected in the CSF and blood of stroke patients and their concentration is related to the extent of brain damage. Antibodies against brain antigens develop after stroke, suggesting a humoral immune response to the brain injury. Furthermore, induced immune tolerance is beneficial in animal models of cerebral ischemia. The presence of circulating T cells sensitized against brain antigens, and antigen presenting cells (APCs carrying brain antigens in draining lymphoid tissue of stroke patients support the notion that stroke might induce antigen-specific immune responses. After stroke, brain proteins that are normally hidden from the periphery, inflammatory mediators, and danger signals can exit the brain through several efflux routes. They can reach the blood after leaking out of the damaged blood-brain barrier or following the drainage of interstitial fluid to the dural venous sinus, or reach the cervical lymph nodes through the nasal lymphatics following CSF drainage along the arachnoid sheaths of nerves across the nasal submucosa. The route and mode of access of brain antigens to lymphoid tissue could influence the type of response. Central and peripheral tolerance prevents autoimmunity, but the actual mechanisms of tolerance to brain antigens released into the periphery in the presence of inflammation, danger signals, and APCs, are not fully characterized. Stroke does not systematically trigger autoimmunity, but under certain circumstances, such as pronounced systemic inflammation or infection, autoreactive T cells could escape the tolerance controls. Further investigation is needed to elucidate whether antigen-specific immune events could underlie neurological complications impairing stroke outcome.

  5. Biomechanical mechanisms underlying exosuit-induced improvements in walking economy after stroke.

    Science.gov (United States)

    Bae, Jaehyun; Awad, Louis N; Long, Andrew; O'Donnell, Kathleen; Hendron, Katy; Holt, Kenneth G; Ellis, Terry D; Walsh, Conor J

    2018-03-07

    Stroke-induced hemiparetic gait is characteristically asymmetric and metabolically expensive. Weakness and impaired control of the paretic ankle contribute to reduced forward propulsion and ground clearance - walking subtasks critical for safe and efficient locomotion. Targeted gait interventions that improve paretic ankle function after stroke are therefore warranted. We have developed textile-based, soft wearable robots that transmit mechanical power generated by off-board or body-worn actuators to the paretic ankle using Bowden cables (soft exosuits) and have demonstrated the exosuits can overcome deficits in paretic limb forward propulsion and ground clearance, ultimately reducing the metabolic cost of hemiparetic walking. This study elucidates the biomechanical mechanisms underlying exosuit-induced reductions in metabolic power. We evaluated the relationships between exosuit-induced changes in the body center of mass (COM) power generated by each limb, individual joint power and metabolic power. Compared with walking with an exosuit unpowered, exosuit assistance produced more symmetrical COM power generation during the critical period of the step-to-step transition (22.4±6.4% more symmetric). Changes in individual limb COM power were related to changes in paretic ( R 2 =0.83, P= 0.004) and non-paretic ( R 2 = 0.73, P= 0.014) ankle power. Interestingly, despite the exosuit providing direct assistance to only the paretic limb, changes in metabolic power were related to changes in non-paretic limb COM power ( R 2 =0.80, P= 0.007), not paretic limb COM power ( P> 0.05). These findings contribute to a fundamental understanding of how individuals post-stroke interact with an exosuit to reduce the metabolic cost of hemiparetic walking. © 2018. Published by The Company of Biologists Ltd.

  6. Brain control of volitional ankle tasks in people with chronic stroke and in healthy individuals.

    Science.gov (United States)

    Beaulieu, L D; Massé-Alarie, H; Brouwer, B; Schneider, C

    2014-03-15

    This study explored the relationships between motor cortical control of ankle dorsiflexors and clinical impairments of volitional ankle dorsiflexion in people with chronic stroke. Eighteen persons with stroke and 14 controls were evaluated. Clinical tools were used to assess ankle dorsiflexion amplitude and isometric strength. Transcranial magnetic stimulation (TMS) of the primary motor cortex (M1) tested the functional integrity of cortical circuits controlling the tibialis anterior (TA). All clinical scores and most TMS outcomes were impaired in people with chronic stroke. The lower clinical scores were related to the reduction of the strength of corticospinal projections onto spinal motoneurons. Concurrent TMS and clinical testing in chronic stroke provided original data demonstrating relationships between the integrity of cortical and corticospinal components of TA motor control and volitional ankle tasks. Our study proposes that volitional ankle mobilization in chronic stroke may be explained by the residual abnormal M1 circuits which may be responsive for rehabilitation intervention. This should be confirmed in longitudinal studies with larger samples to determine whether TMS outcomes associated with lower limb muscles are predictive of clinical changes or vice versa. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Effect of shivering on brain tissue oxygenation during induced normothermia in patients with severe brain injury.

    Science.gov (United States)

    Oddo, Mauro; Frangos, Suzanne; Maloney-Wilensky, Eileen; Andrew Kofke, W; Le Roux, Peter D; Levine, Joshua M

    2010-02-01

    We analyzed the impact of shivering on brain tissue oxygenation (PbtO(2)) during induced normothermia in patients with severe brain injury. We studied patients with severe brain injury who developed shivering during induced normothermia. Induced normothermia was applied to treat refractory fever (body temperature [BT] > or =38.3 degrees C, refractory to conventional treatment) using a surface cooling device with computerized adjustment of patient BT target to 37 +/- 0.5 degrees C. PbtO(2), intracranial pressure, mean arterial pressure, cerebral perfusion pressure, and BT were monitored continuously. Circulating water temperature of the device system was measured to assess the intensity of cooling. Fifteen patients (10 with severe traumatic brain injury, 5 with aneurysmal subarachnoid hemorrhage) were treated with induced normothermia for an average of 5 +/- 2 days. Shivering caused a significant decrease in PbtO(2) levels both in SAH and TBI patients. Compared to baseline, shivering was associated with an overall reduction of PbtO(2) from 34.1 +/- 7.3 to 24.4 +/- 5.5 mmHg (P shivering-associated decrease of PbtO(2) (DeltaPbtO(2)) and circulating water temperature (R = 0.82, P shivering was associated with a significant decrease of PbtO(2), which correlated with the intensity of cooling. Monitoring of therapeutic cooling with computerized thermoregulatory systems may help prevent shivering and optimize the management of induced normothermia. The clinical significance of shivering-induced decrease in brain tissue oxygenation remains to be determined.

  8. Pathophysiology of brain ischemia as it relates to the therapy of acute ischemic stroke

    DEFF Research Database (Denmark)

    Lassen, N A

    1990-01-01

    Current knowledge of the pathophysiology of cerebral ischemia, summarized in the present study, predicts that neurological deficits caused by moderate ischemia (flows in the penumbral range between 23 and 10 ml/100 g/min) are reversible provided flow is restored within 3-4 h of onset. It also...... predicts that areas of dense ischemia cannot be salvaged and that reperfusion of such areas is risky, because massive edema or even hemorrhage may develop following reperfusion. On this basis, it is argued that selection of stroke cases for thrombolysis or surgical revascularization must be based not only...... on computed tomographic (CT) scanning to exclude hemorrhagic stroke, but also on cerebral blood flow (CBF) tomography to exclude lacunar infarcts, early reperfusion, and dense ischemia. The methods available for routing CBF tomography in acute stroke cases are discussed, and it is concluded that single photon...

  9. Cognitive rehabilitation for executive dysfunction in adults with stroke or other adult non-progressive acquired brain damage.

    Science.gov (United States)

    Chung, Charlie S Y; Pollock, Alex; Campbell, Tanya; Durward, Brian R; Hagen, Suzanne

    2013-04-30

    Executive functions are the controlling mechanisms of the brain and include the processes of planning, initiation, organisation, inhibition, problem solving, self monitoring and error correction. They are essential for goal-oriented behaviour and responding to new and novel situations. A high number of people with acquired brain injury, including around 75% of stroke survivors, will experience executive dysfunction. Executive dysfunction reduces capacity to regain independence in activities of daily living (ADL), particularly when alternative movement strategies are necessary to compensate for limb weakness. Improving executive function may lead to increased independence with ADL. There are various cognitive rehabilitation strategies for training executive function used within clinical practice and it is necessary to determine the effectiveness of these interventions. To determine the effects of cognitive rehabilitation on executive dysfunction for adults with stroke or other non-progressive acquired brain injuries. We searched the Cochrane Stroke Group Trials Register (August 2012), the Cochrane Central Register of Controlled Trials (The Cochrane Library, August 2012), MEDLINE (1950 to August 2012), EMBASE (1980 to August 2012), CINAHL (1982 to August 2012), PsycINFO (1806 to August 2012), AMED (1985 to August 2012) and 11 additional databases. We also searched reference lists and trials registers, handsearched journals and conference proceedings, and contacted experts. We included randomised trials in adults after non-progressive acquired brain injury, where the intervention was specifically targeted at improving cognition including separable executive function data (restorative interventions), where the intervention was aimed at training participants in methods to compensate for lost executive function (compensative interventions) or where the intervention involved the training in the use of an adaptive technique for improving independence with ADL (adaptive

  10. Investigations of primary blast-induced traumatic brain injury

    Science.gov (United States)

    Sawyer, T. W.; Josey, T.; Wang, Y.; Villanueva, M.; Ritzel, D. V.; Nelson, P.; Lee, J. J.

    2018-01-01

    The development of an advanced blast simulator (ABS) has enabled the reproducible generation of single-pulse shock waves that simulate free-field blast with high fidelity. Studies with rodents in the ABS demonstrated the necessity of head restraint during head-only exposures. When the head was not restrained, violent global head motion was induced by pressures that would not produce similar movement of a target the size and mass of a human head. This scaling artefact produced changes in brain function that were reminiscent of traumatic brain injury (TBI) due to impact-acceleration effects. Restraint of the rodent head eliminated these, but still produced subtle changes in brain biochemistry, showing that blast-induced pressure waves do cause brain deficits. Further experiments were carried out with rat brain cell aggregate cultures that enabled the conduct of studies without the gross movement encountered when using rodents. The suspension nature of this model was also exploited to minimize the boundary effects that complicate the interpretation of primary blast studies using surface cultures. Using this system, brain tissue was found not only to be sensitive to pressure changes, but also able to discriminate between the highly defined single-pulse shock waves produced by underwater blast and the complex pressure history exposures experienced by aggregates encased within a sphere and subjected to simulated air blast. The nature of blast-induced primary TBI requires a multidisciplinary research approach that addresses the fidelity of the blast insult, its accurate measurement and characterization, as well as the limitations of the biological models used.

  11. Prospective clinical biomarkers of caspase-mediated apoptosis associated with neuronal and neurovascular damage following stroke and other severe brain injuries: Implications for chronic neurodegeneration

    Directory of Open Access Journals (Sweden)

    Olena Y Glushakova

    2017-01-01

    Full Text Available Acute brain injuries, including ischemic and hemorrhagic stroke, as well as traumatic brain injury (TBI, are major worldwide health concerns with very limited options for effective diagnosis and treatment. Stroke and TBI pose an increased risk for the development of chronic neurodegenerative diseases, notably chronic traumatic encephalopathy, Alzheimer's disease, and Parkinson's disease. The existence of premorbid neurodegenerative diseases can exacerbate the severity and prognosis of acute brain injuries. Apoptosis involving caspase-3 is one of the most common mechanisms involved in the etiopathology of both acute and chronic neurological and neurodegenerative diseases, suggesting a relationship between these disorders. Over the past two decades, several clinical biomarkers of apoptosis have been identified in cerebrospinal fluid and peripheral blood following ischemic stroke, intracerebral and subarachnoid hemorrhage, and TBI. These biomarkers include selected caspases, notably caspase-3 and its specific cleavage products such as caspase-cleaved cytokeratin-18, caspase-cleaved tau, and a caspase-specific 120 kDa αII-spectrin breakdown product. The levels of these biomarkers might be a valuable tool for the identification of pathological pathways such as apoptosis and inflammation involved in injury progression, assessment of injury severity, and prediction of clinical outcomes. This review focuses on clinical studies involving biomarkers of caspase-3-mediated pathways, following stroke and TBI. The review further examines their prospective diagnostic utility, as well as clinical utility for improved personalized treatment of stroke and TBI patients and the development of prophylactic treatment chronic neurodegenerative disease.

  12. Tumor sterilization dose and radiation induced change of the brain tissue in radiotherapy of brain tumors

    International Nuclear Information System (INIS)

    Yoshii, Yoshihiko; Maki, Yutaka; Takano, Shingo

    1987-01-01

    Ninety-seven patients with brain tumors (38 gliomas, 26 brain metastases, 18 sellar tumors, 15 others) were treated by cobalt gamma ray or proton radiotherapy. In this study, normal brain injury due to radiation was analysed in terms of time-dose-fractionation (TDF), nominal standard dose (NSD) by the Ellis formula and NeuNSD by a modification in which the N exponent was -0.44 and the T exponent was -0.06. Their calculated doses were analysed in relationship to the normal brain radiation induced change (RIC) and the tumor sterilization dose. All brain tumors with an exception of many patients with brain metastases were received a surgical extirpation subtotally or partially prior to radiotherapy. And all patients with glioma and brain metastasis received also immuno-chemotherapy in the usual manner during radiotherapy. The calculated dose expressed by NeuNSD and TDF showed a significant relationship between a therapeutic dose and a postradiation time in terms of the appearance of RIC. It was suggested that RIC was caused by a dose over 800 in NeuNSD and a dose over 70 in TDF. Furthermore, it was suggested that an aged patient and a patient who had the vulnerable brain tissue to radiation exposure in the irradiated field had the high risk of RIC. On the other hand, our results suggested that the tumor sterilization dose should be over 1,536 NeuNSD and the irradiated method should be further considered in addition to the radiobiological concepts for various brain tumors. (author)

  13. Non-pharmacological interventions for perceptual disorders following stroke and other adult-acquired, non-progressive brain injury.

    Science.gov (United States)

    Bowen, Audrey; Knapp, Peter; Gillespie, David; Nicolson, Donald J; Vail, Andy

    2011-04-13

    Stroke and other adult-acquired brain injury may impair perception leading to distress and increased dependence on others. Perceptual rehabilitation includes functional training, sensory stimulation, strategy training and task repetition. To examine the evidence for improvement in activities of daily living (ADL) six months post randomisation for active intervention versus placebo or no treatment. We searched the trials registers of the Cochrane Stroke Group and the Cochrane Infectious Diseases Group (May 2009) but not the Injuries Group, the Cochrane Central Register of Controlled Trials (The Cochrane Library 2009, Issue 3), MEDLINE (1950 to August 2009), EMBASE (1980 to August 2009), CINAHL (1982 to August 2009), PsycINFO (1974 to August 2009), REHABDATA and PsycBITE (May to June 2009). We also searched trials and research registers, handsearched journals, searched reference lists and contacted authors. Randomised controlled trials of adult stroke or acquired brain injury. Our definition of perception excluded visual field deficits, neglect/inattention and apraxia. One review author assessed titles, abstracts and keywords for eligibility. At least two review authors independently extracted data. We requested unclear or missing information from corresponding authors. We included six single-site trials in rehabilitation settings, involving 338 participants. Four trials included people with only stroke. All studies provided sensory stimulation, sometimes with another intervention. Sensory stimulation typically involved practising tasks that required visuo-perceptual processing with occupational therapist assistance. Repetition was never used and only one study included functional training. No trials provided data on longer term improvement in ADL scores. Only three trials provided any data suitable for analysis. Two of these trials compared active to placebo intervention. There was no evidence of a difference in ADL scores at the scheduled end of intervention: mean

  14. The effect of pre-nutrition of hydroalcoholic extractof Origanum vulgare on brain edema and neurologic deficits in a rat stroke model

    Directory of Open Access Journals (Sweden)

    Meysam Foroozandeh

    2015-10-01

    Full Text Available Background and Aim: Stroke is one of the most important factors of mortality and disability in the world. Free radicals are produced following ischemic stroke and they play a central role in breaking the blood-brain barrier and  causing brain edema formation. The aim of the current study was to evaluate the effect of hydro- alcoholic extract of Origanum vulgare on brain edema and neurologic deficit in a rat stroke model. Materials and Methods: In thisexperimental study, 35 male Wistar rats were randomly divided into 5 equal groups.  The first  two groups (control and Sham received distilled water, while three treatment groups received oral Origanum vulgare extract for 30days (50,75and 100 mg/kgdaily, respectively.  Two hours after the last dose of Origanum vulgare extract,each main group underwent  a 60 min middle cerebral artery occlusion.  Then, the assessment of blood brain edema, and neurologic deficits analysis were done . Brain edema (brain water content was analyzed by One-Way ANOVA using LSD method and neurologic deficits analysis by means of Mann-Whitney U, and P<0.05 was taken as the significant level. Results: Origanum vulgare extract reduced brain edema in the experimental groups of 50 (82.49±0.47, 75 (80.89±0.63 and 100 mg/kg/day (80.80±0.66 compared to the control group (84.46±0.67. The neurologic deficit scores in the experimental groups of 75and 100mg/kg/day, compared with control group, but neurologic deficit scores did not affect the group receiving the dose 50 mg/kg. Conclusion:  The obtained data indicate that Origanum vulgar extract via reduction of brain edema and neurologic deficits scorescan have a protective effect on the stroke model.

  15. SPET brain imaging with thallium 201 diethyldithiocarbamate in acute ischaemic stroke

    International Nuclear Information System (INIS)

    Bruine, J.F. de; Limburg, M.; Royen, E.A. van; Hijdra, A.; Hill, T.C.; Schoot, J.B. van der; Amsterdam Univ.; New England Deaconess Hospital, Boston, MA

    1990-01-01

    Thirty-five patients with acute ischaemic stroke were studied within 24 h after hospital admission with thallium diethyldithiocarbamate Tl 201 single photon emission tomography ( 201 Tl-DDC SPET) and X-ray computed tomography (CT). 201 Tl-DDC is a non-redistributing agent that allows postponed imaging after early administration and early therapeutic intervention. In 16 patients both investigations were performed within 24 h after stroke onset. The sensitivity of SPET was 94% and of CT 81% in the first 24 h, when hypodensity and obliteration of sulci were used as CT reading criteria. When only hypodensity was used as a criterion, the sensitivity of CT was 50% in this group. Sensitivity of CT compared with SPET became increasingly better in patients with older infarcts (1-18 days). In two-thirds of patients, the lesion demonstrated on SPET was larger than that on CT, and this was especially so with older infarcts. Crossed cerebellar diaschisis occurred in 69% of patients. The high sensitivity of 201 Tl-DDC SPET in the first 24 h after ischaemic stroke and the favourable properties of this radiopharmaceutical make it a method of interest in the assessment of initial perfusion defects in early experimental stroke therapies. (orig.)

  16. Tissue is more important than time: insights into acute ischemic stroke from modern brain imaging.

    Science.gov (United States)

    Bivard, Andrew; Parsons, Mark

    2018-02-01

    The clinical practice of acute ischemic stroke treatment has undergone a major change over the last 5 years, as multimodal imaging becomes more accessible, and evidence mounts that individualized treatment is possible. Multimodal imaging performed before treatment provides invaluable information to treating clinicians, which includes confirmation of the diagnosis, and provides guidance on the appropriateness and the likely outcome of intravenous or endovascular treatment for individual patients (and their families). However, often health systems struggle to keep pace with science; thus, a one-size fits all protocol-driven basic imaging approach is still the norm in many stroke centers. Comprehensive multimodal computed tomography (CT) (incorporating noncontrast CT, CT angiography, and perfusion CT) provides rapid, reliable information about stroke pathophysiology that cannot be provided by more limited imaging prior to treatment. Multimodal CT identifies treatment responders for both intravenous thrombolysis and endovascular therapy. Now we are in the era of thrombectomy, the use of multimodal imaging routinely to guide treatment can no longer be avoided. In light of the ground breaking thrombectomy trial results and previous studies validating the use of multimodal imaging, there is now a strong rationale for performing comprehensive multimodal CT assessments before treatment as a standard of care for all stroke patients.

  17. Experiences of participation in goal setting for people with stroke-induced aphasia in Norway. A qualitative study.

    Science.gov (United States)

    Berg, Karianne; Askim, Torunn; Balandin, Susan; Armstrong, Elizabeth; Rise, Marit By

    2017-06-01

    The body of research into client participation in aphasia rehabilitation is increasing, but the evidence on how it is implemented into clinical practice is still scarce. Particularly, the importance of including the "insider's perspective" has been demanded. The aim of this study was to explore how people with aphasia experienced client participation during the process of goal setting and clinical decision making in language rehabilitation. Fifteen people with stroke-induced aphasia participated in semi-structured in-depth interviews. A qualitative analysis using Systematic Text Condensation was undertaken. Analysis revealed four main themes: (1) pleased with services, (2) vagueness in language rehabilitation, (3) personal goals exist, and (4) desired level of participation. Even though people with stroke-induced aphasia overall are pleased with the language rehabilitation, there is a need for greater emphasis on making the framework of language rehabilitation less vague. Therapists should also spend more time on collaboration with people with stroke-induced aphasia and use available methods to support communication and collaboration. The findings underscore the need for further exploration of the potential outcomes of implementing client participation in goal setting and clinical decision making for persons with stroke-induced aphasia. Implications for rehabilitation All persons with stroke induced aphasia should be asked about their goals for rehabilitation not only once, but during the whole continuum of their rehabilitation journey. Rehabilitation professionals should place greater emphasis on client participation by asking people with stroke induced aphasia how they prefer to participate at different stages of rehabilitation. To ensure active participation for those who wants it, existing tools and techniques which promoted collaborative goal setting should be better incorporated.

  18. 99mTc-bicisate reliably images CBF in chronic brain diseases but fails to show reflow hyperemia in subacute stroke

    DEFF Research Database (Denmark)

    Lassen, N A; Sperling, B

    1994-01-01

    of 115 cases were collected, and of these 105 were considered technically adequate, comprising 18 normal subjects, 18 senile dementia, eight epilepsy, one brain tumor, eight chronic head trauma, and 52 stroke cases. As expected, bicisate gave better spatial resolution than Xe. Agreement between...... a normal or elevated flow (luxury perfusion) as sign of spontaneous thrombolysis with reperfusion; in fact, these seven cases comprised all the reperfusion cases in the series. The results validate bicisate as a tracer of CBF in normal humans and in chronic brain diseases. Only in a subgroup of subacute...... stroke cases does bicisate not follow CBF, as it fails to show reperfusion hyperemia. This suggests the usefulness of bicisate in stroke cases, particularly in the subacute phase, where other SPECT methods often present difficulties due to reflow masking the size and the severity of the lesion....

  19. Prevalence of stenoses and occlusions of brain-supplying arteries in young stroke patients.

    LENUS (Irish Health Repository)

    von Sarnowski, Bettina

    2013-03-06

    OBJECTIVE: Atherosclerosis is believed to be a minor cause of TIA and stroke in younger and middle-aged patients. However, data from large cohorts are limited. This study investigates the prevalence of extracranial and intracranial atherosclerosis in stroke and TIA patients aged 18-55 years in the multinational sifap1 study. METHODS: From the sifap1 cohort (n = 5,023), we analyzed a subset of patients with complete data from carotid ultrasound studies. Patients with arterial dissections, vasculitis, and mobile thrombi were excluded. Among the remaining 2,187 patients (men: n = 1,319; 18-44 years: n = 744), intracranial arteries were additionally examined with ultrasonography in 1,612 patients (73.7%). Patients were stratified by sex and age groups (younger: 18-44 years; middle-aged: 45-55 years). RESULTS: In patients with ischemic stroke, the overall prevalence of carotid artery stenoses and occlusions was 8.9% (younger: 4.9%; middle-aged: 11.0%), of which 81% were symptomatic. Nonstenotic carotid plaques were more common in men than in women (15.8% vs 7.7%; p < 0.001), and in middle-aged than in younger patients (17.0% vs 4.9%; p < 0.001). Supratentorial intracranial artery stenoses and occlusions amounted to 11.8%. Supratentorial stenoses occurred more frequently in middle-aged patients (13.0% vs 7.8%; p < 0.001), whereas occlusions were equally common (both 3.2%; not significant). CONCLUSIONS: We observed a substantial proportion of atherosclerotic carotid artery stenoses and occlusions in younger stroke patients. Intracranial stenoses and occlusions were even more prevalent than extracranial carotid artery disease. Together with nonstenotic plaques, one-fifth of patients (21.2%) had symptomatic or asymptomatic large-artery atherosclerosis, which should encourage future stroke prevention campaigns to target risk factor modification in young people.

  20. Head movement during CT brain perfusion acquisition of patients with suspected acute ischemic stroke

    International Nuclear Information System (INIS)

    Fahmi, F.; Beenen, L.F.M.; Streekstra, G.J.; Janssen, N.Y.; Jong, H.W. de; Riordan, A.; Roos, Y.B.; Majoie, C.B.; Bavel, E. van; Marquering, H.A.

    2013-01-01

    Objective: Computed Tomography Perfusion (CTP) is a promising tool to support treatment decision for acute ischemic stroke patients. However, head movement during acquisition may limit its applicability. Information of the extent of head motion is currently lacking. Our purpose is to qualitatively and quantitatively assess the extent of head movement during acquisition. Methods: From 103 consecutive patients admitted with suspicion of acute ischemic stroke, head movement in 220 CTP datasets was qualitatively categorized by experts as none, minimal, moderate, or severe. The movement was quantified using 3D registration of CTP volume data with non-contrast CT of the same patient; yielding 6 movement parameters for each time frame. The movement categorization was correlated with National Institutes of Health Stroke Scale (NIHSS) score and baseline characteristic using multinomial logistic regression and student's t-test respectively. Results: Moderate and severe head movement occurred in almost 25% (25/103) of all patients with acute ischemic stroke. The registration technique quantified head movement with mean rotation angle up to 3.6° and 14°, and mean translation up to 9.1 mm and 22.6 mm for datasets classified as moderate and severe respectively. The rotation was predominantly in the axial plane (yaw) and the main translation was in the scan direction. There was no statistically significant association between movement classification and NIHSS score and baseline characteristics. Conclusions: Moderate or severe head movement during CTP acquisition of acute stroke patients is quite common. The presented registration technique can be used to automatically quantify the movement during acquisition, which can assist identification of CTP datasets with excessive head movement

  1. The effects of an 8-week computer-based brain training programme on cognitive functioning, QoL and self-efficacy after stroke.

    Science.gov (United States)

    Wentink, M M; Berger, M A M; de Kloet, A J; Meesters, J; Band, G P H; Wolterbeek, R; Goossens, P H; Vliet Vlieland, T P M

    2016-10-01

    Cognitive impairment after stroke has a direct impact on daily functioning and quality of life (QoL) of patients and is associated with higher mortality and healthcare costs. The aim of this study was to determine the effect of a computer-based brain training programme on cognitive functioning, QoL and self-efficacy compared to a control condition in stroke patients. Stroke patients with self-perceived cognitive impairment were randomly allocated to the intervention or control group. The intervention consisted of an 8-week brain training programme (Lumosity Inc.®). The control group received general information about the brain weekly. Assessments consisted of a set of neuropsychological tests and questionnaires. In addition, adherence with trained computer tasks was recorded. No effect of the training was found on cognitive functioning, QoL or self-efficacy when compared to the control condition, except for very limited effects on working memory and speed. This study found very limited effects on neuropsychological tests that were closely related to trained computer tasks, but no transfers to other tests or self-perceived cognitive failures, QoL or self-efficacy. These findings warrant the need for further research into the value of computer-based brain training to improve cognitive functioning in the chronic phase after stroke.

  2. Improving Walking Capacity by Surgical Correction of Equinovarus Foot Deformity in Adult Patients with Stroke Or Traumatic Brain Injury: A Systematic Review

    NARCIS (Netherlands)

    Renzenbrink, G.J.; Buurke, J.H.; Nene, A.V.; Geurts, A.C.H.; Kwakkel, G.; Rietman, J.S.

    2012-01-01

    Objective: Equinovarus foot deformity following stroke or traumatic brain injury compromises walking capacity, interfering with activities of daily living. In soft-tissue surgery the imbalanced muscles responsible for the deviant position of the ankle and foot are lengthened, released and/or

  3. Acupuncture at Waiguan (TE5) influences activation/deactivation of functional brain areas in ischemic stroke patients and healthy people: A functional MRI study.

    Science.gov (United States)

    Chen, Junqi; Huang, Yong; Lai, Xinsheng; Tang, Chunzhi; Yang, Junjun; Chen, Hua; Zeng, Tongjun; Wu, Junxian; Qu, Shanshan

    2013-01-25

    In the present study, 10 patients with ischemic stroke in the left hemisphere and six healthy controls were subjected to acupuncture at right Waiguan (TE5). In ischemic stroke subjects, functional MRI showed enhanced activation in Broadmann areas 5, 6, 7, 18, 19, 24, 32, the hypothalamic inferior lobe, the mamillary body, and the ventral posterolateral nucleus of the left hemisphere, and Broadmann areas 4, 6, 7, 18, 19 and 32 of the right hemisphere, but attenuated activation of Broadmann area 13, the hypothalamic inferior lobe, the posterior lobe of the tonsil of cerebellum, and the culmen of the anterior lobe of hypophysis, in the left hemisphere and Broadmann area 13 in the right hemisphere. In ischemic stroke subjects, a number of deactivated brain areas were enhanced, including Broadmann areas 6, 11, 20, 22, 37, and 47, the culmen of the anterior lobe of hypophysis, alae lingulae cerebella, and the posterior lobe of the tonsil of cerebellum of the left hemisphere, and Broadmann areas 8, 37, 45 and 47, the culmen of the anterior lobe of hypophysis, pars tuberalis adenohypophyseos, inferior border of lentiform nucleus, lateral globus pallidus, inferior temporal gyrus, and the parahippocampal gyrus of the right hemisphere. These subjects also exhibited attenuation of a number of deactivated brain areas, including Broadmann area 7. These data suggest that acupuncture at Waiguan specifically alters brain function in regions associated with sensation, vision, and motion in ischemic stroke patients. By contrast, in normal individuals, acupuncture at Waiguan generally activates brain areas associated with insomnia and other functions.

  4. A hybrid brain-machine interface based on EEG and EMG activity for the motor rehabilitation of stroke patients.

    Science.gov (United States)

    Sarasola-Sanz, Andrea; Irastorza-Landa, Nerea; Lopez-Larraz, Eduardo; Bibian, Carlos; Helmhold, Florian; Broetz, Doris; Birbaumer, Niels; Ramos-Murguialday, Ander

    2017-07-01

    Including supplementary information from the brain or other body parts in the control of brain-machine interfaces (BMIs) has been recently proposed and investigated. Such enriched interfaces are referred to as hybrid BMIs (hBMIs) and have been proven to be more robust and accurate than regular BMIs for assistive and rehabilitative applications. Electromyographic (EMG) activity is one of the most widely utilized biosignals in hBMIs, as it provides a quite direct measurement of the motion intention of the user. Whereas most of the existing non-invasive EEG-EMG-hBMIs have only been subjected to offline testings or are limited to one degree of freedom (DoF), we present an EEG-EMG-hBMI that allows the simultaneous control of 7-DoFs of the upper limb with a robotic exoskeleton. Moreover, it establishes a biologically-inspired hierarchical control flow, requiring the active participation of central and peripheral structures of the nervous system. Contingent visual and proprioceptive feedback about the user's EEG and EMG activity is provided in the form of velocity modulation during functional task training. We believe that training with this closed-loop system may facilitate functional neuroplastic processes and eventually elicit a joint brain and muscle motor rehabilitation. Its usability is validated during a real-time operation session in a healthy participant and a chronic stroke patient, showing encouraging results for its application to a clinical rehabilitation scenario.

  5. Brain damage and neurological symptoms induced by T-2 toxin in rat brain.

    Science.gov (United States)

    Guo, Pu; Liu, Aimei; Huang, Deyu; Wu, Qinghua; Fatima, Zainab; Tao, Yanfei; Cheng, Guyue; Wang, Xu; Yuan, Zonghui

    2018-04-01

    T-2 toxin, a trichothecene mycotoxin, is a common contaminant in food and animal feed, and is also present in processed cereal products. The most common route of T-2 toxin exposure in humans is through dietary ingestion. The cytotoxic effects of T-2 toxin include modifications to feeding behavior, nervous disorders, cardiovascular alterations, immunosuppression, and hemostatic derangements. However, to date, effects on the central nervous system (CNS) have rarely been reported. In the present study, female Wistar rat were given a single dose of T-2 toxin at 2 mg/kg b.w. and were sacrificed at one, three, and seven days post-exposure. Histopathological analysis and transmission electron microscope (TEM) observations were used to investigate injury to the brain and pituitary gland. Damage to the brain and pituitary at the molecular level was detected by real time-polymerase chain reaction (RT-PCR), western blot, and immunohistochemical assays. Liquid chromatograph-mass spectrometer/mass spectrometer (LC-MS/MS) was used to investigate T-2 concentration in the brain. The results showed that pathological lesions were obvious in the brain at three days post-exposure; lesions in the pituitary were not observed until seven days post-exposure. Autophagy in the brain and apoptosis in the pituitary suggest that T-2 toxin may induce different acute reactions in different tissues. Importantly, low concentrations of T-2 toxin in the brain were observed in only one rat. Responsible for the above mentioned, we hypothesize that brain damage caused by this toxin may be due to the ability of the toxin to directly cross the blood-brain barrier (BBB). Therefore, given its widespread pollution in food, we should pay more attention to the neurotoxic effects of the T-2 toxin, which may have widespread implications for human health. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Magnetic resonance imaging of blood-brain barrier permeability in ischemic stroke using diffusion-weighted arterial spin labeling in rats.

    Science.gov (United States)

    Tiwari, Yash V; Lu, Jianfei; Shen, Qiang; Cerqueira, Bianca; Duong, Timothy Q

    2017-08-01

    Diffusion-weighted arterial spin labeling magnetic resonance imaging has recently been proposed to quantify the rate of water exchange (K w ) across the blood-brain barrier in humans. This study aimed to evaluate the blood-brain barrier disruption in transient (60 min) ischemic stroke using K w magnetic resonance imaging with cross-validation by dynamic contrast-enhanced magnetic resonance imaging and Evans blue histology in the same rats. The major findings were: (i) at 90 min after stroke (30 min after reperfusion), group K w magnetic resonance imaging data showed no significant blood-brain barrier permeability changes, although a few animals showed slightly abnormal K w . Dynamic contrast-enhanced magnetic resonance imaging confirmed this finding in the same animals. (ii) At two days after stroke, K w magnetic resonance imaging revealed significant blood-brain barrier disruption. Regions with abnormal K w showed substantial overlap with regions of hyperintense T 2 (vasogenic edema) and hyperperfusion. Dynamic contrast-enhanced magnetic resonance imaging and Evans blue histology confirmed these findings in the same animals. The K w values in the normal contralesional hemisphere and the ipsilesional ischemic core two days after stroke were: 363 ± 17 and 261 ± 18 min -1 , respectively (P < 0.05, n = 9). K w magnetic resonance imaging is sensitive to blood-brain barrier permeability changes in stroke, consistent with dynamic contrast-enhanced magnetic resonance imaging and Evans blue extravasation. K w magnetic resonance imaging offers advantages over existing techniques because contrast agent is not needed and repeated measurements can be made for longitudinal monitoring or averaging.

  7. Music for the ageing brain: Cognitive, emotional, social, and neural benefits of musical leisure activities in stroke and dementia.

    Science.gov (United States)

    Särkämö, Teppo

    2017-01-01

    Music engages an extensive network of auditory, cognitive, motor, and emotional processing regions in the brain. Coupled with the fact that the emotional and cognitive impact of music is often well preserved in ageing and dementia, music is a powerful tool in the care and rehabilitation of many ageing-related neurological diseases. In addition to formal music therapy, there has been a growing interest in self- or caregiver-implemented musical leisure activities or hobbies as a widely applicable means to support psychological wellbeing in ageing and in neurological rehabilitation. This article reviews the currently existing evidence on the cognitive, emotional, and neural benefits of musical leisure activities in normal ageing as well as in the rehabilitation and care of two of the most common and ageing-related neurological diseases: stroke and dementia.

  8. Transtentorial diachisis in stroke patients demonstrated by I-123 HIPDM brain imaging

    International Nuclear Information System (INIS)

    Shih, W.J.; DeKosky, S.; Coupal, J.J.; Clark, D.; Ryo, U.Y.; Kung, H.F.

    1988-01-01

    SPECT and planar images of 35 patients with stroke were compared with images of 26 patients with Alzheimer disease, two with Creutzfeldt-Jakob disease, and one with schizoaffective disorder. Transtentorial diaschisis (TTD) with decreased cerebellar activity was shown in 18 patients with large infarcts of middle cerebral artery (MCA) territory and in four patients with internal capsule and basal ganglia infarcts. No TTD was shown in the 29 patients without stroke and those with small infarcts. Decreased cerebral activity contralateral to cerebral infarct due to interruption of cerebellar flow in TTD was hypothesized. The authors concluded that TTD occurs exclusively in an extensive cerebral infarct of the MCA territory, and an absent cortical perfusion abnormality with presence of TTD may indicate basal ganglia and/or internal capsule infarct

  9. [Elements of system semiotics of the brain and head with cranial vessels of patients with stroke and with risk of stroke development].

    Science.gov (United States)

    Makomela, N M

    2007-01-01

    By means of a multispiral computer and magnetic resonance tomography 211 patients with an ischemic stroke, 109 patients with hemorrhagic stroke, 41 patients with an arterial hypertensia, 43 patients with aneurism, 58 patients with discirculation encephalopathy, 125 patients with ischemic illness of heart, practically healthy 62 have been observed. The author found high frequency of pathological deformations of carotid and vertebral arteries of not closed arterial circle, calcification of the pineal body and vascular plexus of lateral ventricles. cysts of maxillary sinuses of patients with stroke in comparison with patients at risk of the development of stroke and practically healthy subjects.

  10. Cannabidiol reduces brain damage and improves functional recovery in a neonatal rat model of arterial ischemic stroke.

    Science.gov (United States)

    Ceprián, Maria; Jiménez-Sánchez, Laura; Vargas, Carlos; Barata, Lorena; Hind, Will; Martínez-Orgado, Jose

    2017-04-01

    and purpose: Currently there is no effective treatment for neonatal arterial ischemic stroke (AIS). Cannabidiol (CBD) is neuroprotective in models of newborn hypoxic-ischemic brain damage and adult stroke. The purpose of this work was to study the protective effect of CBD in a neonatal rat model of AIS. Middle Cerebral Artery Occlusion (MCAO) was achieved in neonatal Wistar rats by introducing a nylon filament to the left MCA for 3 h; 15 min after removing the occluder vehicle (MCAO-V) or CBD single dose 5 mg/kg (MCAO-C) were administered i. p. Similarly manipulated but non-occluded rats served as controls (SHM). A set of behavioral tests was then conducted one week (P15) or one month (P38) after MCAO. Brain damage was then assessed by magnetic resonance imaging (MRI), proton magnetic resonance spectroscopy (H + -MRS) and histologic (TUNEL for cell death, immunohistochemistry for neuron, astrocyte and microglia identification) studies. CBD administration improved neurobehavioral function regarding strength, hemiparesis, coordination and sensorimotor performance as assessed at P15 and P38. MRI indicated that CBD did not reduce the volume of infarct but reduced the volume of perilesional gliosis. H + -MRS indicated that CBD reduced metabolic derangement and excitotoxicty, and protected astrocyte function. Histologic studies indicated that CBD reduced neuronal loss and apoptosis, and modulated astrogliosis and microglial proliferation and activation. CBD administration after MCAO led to long-term functional recovery, reducing neuronal loss and astrogliosis, and modulating apoptosis, metabolic derangement, excitotoxicity and neuro-inflammation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Prostaglandin E2 EP2 Receptor Deletion Attenuates Intracerebral Hemorrhage-Induced Brain Injury and Improves Functional Recovery

    Directory of Open Access Journals (Sweden)

    Jenna L. Leclerc

    2015-04-01

    Full Text Available Intracerebral hemorrhage (ICH is a devastating type of stroke characterized by bleeding into the brain parenchyma and secondary brain injury resulting from strong neuroinflammatory responses to blood components. Production of prostaglandin E2 (PGE2 is significantly upregulated following ICH and contributes to this inflammatory response in part through its E prostanoid receptor subtype 2 (EP2. Signaling through the EP2 receptor has been shown to affect outcomes of many acute and chronic neurological disorders; although, not yet explored in the context of ICH. Wildtype (WT and EP2 receptor knockout (EP2−/− mice were subjected to ICH, and various anatomical and functional outcomes were assessed by histology and neurobehavioral testing, respectively. When compared with age-matched WT controls, EP2−/− mice had 41.9 ± 4.7% smaller ICH-induced brain lesions and displayed significantly less ipsilateral hemispheric enlargement and incidence of intraventricular hemorrhage. Anatomical outcomes correlated with improved functional recovery as identified by neurological deficit scoring. Histological staining was performed to begin investigating the mechanisms involved in EP2-mediated neurotoxicity after ICH. EP2−/− mice exhibited 45.5 ± 5.8% and 41.4 ± 8.1% less blood and ferric iron accumulation, respectively. Furthermore, significantly less striatal and cortical microgliosis, striatal and cortical astrogliosis, blood–brain barrier breakdown, and peripheral neutrophil infiltration were seen in EP2−/− mice. This study is the first to suggest a deleterious role for the PGE2-EP2 signaling axis in modulating brain injury, inflammation, and functional recovery following ICH. Targeting the EP2 G protein-coupled receptor may represent a new therapeutic avenue for the treatment of hemorrhagic stroke.

  12. Pharmacological targeting of secondary brain damage following ischemic or hemorrhagic stroke, traumatic brain injury, and bacterial meningitis - a systematic review and meta-analysis.

    Science.gov (United States)

    Beez, Thomas; Steiger, Hans-Jakob; Etminan, Nima

    2017-12-07

    The effectiveness of pharmacological strategies exclusively targeting secondary brain damage (SBD) following ischemic stroke, aneurysmal subarachnoid hemorrhage, aSAH, intracerebral hemorrhage (ICH), traumatic brain injury (TBI) and bacterial meningitis is unclear. This meta-analysis studied the effect of SBD targeted treatment on clinical outcome across the pathological entities. Randomized, controlled, double-blinded trials on aforementioned entities with 'death' as endpoint were identified. Effect sizes were analyzed and expressed as pooled risk ratio (RR) estimates with 95% confidence intervals (CI). 123 studies fulfilled the criteria, with data on 66,561 patients. In the pooled analysis, there was a minor reduction of mortality for aSAH [RR 0.93 (95% CI:0.85-1.02)], ICH [RR 0.92 (95% CI:0.82-1.03)] and bacterial meningitis [RR 0.86 (95% CI:0.68-1.09)]. No reduction of mortality was found for ischemic stroke [RR 1.05 (95% CI:1.00-1.11)] and TBI [RR 1.03 (95% CI:0.93-1.15)]. Additional analysis of "poor outcome" as endpoint gave similar results. Subgroup analysis with respect to effector mechanisms showed a tendency towards a reduced mortality for the effector mechanism category "oxidative metabolism/stress" for aSAH with a risk ratio of 0.86 [95% CI: 0.73-1.00]. Regarding specific medications, a statistically significant reduction of mortality and poor outcome was confirmed only for nimodipine for aSAH and dexamethasone for bacterial meningitis. Our results show that only a few selected SBD directed medications are likely to reduce the rate of death and poor outcome following aSAH, and bacterial meningitis, while no convincing evidence could be found for the usefulness of SBD directed medications in ischemic stroke, ICH and TBI. However, a subtle effect on good or excellent outcome might remain undetected. These results should lead to a new perspective of secondary reactions following cerebral injury. These processes should not be seen as suicide mechanisms

  13. Altered Coupling between Motion-Related Activation and Resting-State Brain Activity in the Ipsilesional Sensorimotor Cortex after Cerebral Stroke

    Directory of Open Access Journals (Sweden)

    Jianping Hu

    2017-07-01

    Full Text Available Functional connectivity maps using resting-state functional magnetic resonance imaging (rs-fMRI can closely resemble task fMRI activation patterns, suggesting that resting-state brain activity may predict task-evoked activation or behavioral performance. However, this conclusion was mostly drawn upon a healthy population. It remains unclear whether the predictive ability of resting-state brain activity for task-evoked activation would change under different pathological conditions. This study investigated dynamic changes of coupling between patterns of resting-state functional connectivity (RSFC and motion-related activation in different stages of cerebral stroke. Twenty stroke patients with hand motor function impairment were involved. rs-fMRI and hand motion-related fMRI data were acquired in the acute, subacute, and early chronic stages of cerebral stroke on a 3-T magnetic resonance (MR scanner. Sixteen healthy participants were enrolled as controls. For each subject, an activation map of the affected hand was first created using general linear model analysis on task fMRI data, and then an RSFC map was determined by seeding at the peak region of hand motion activation during the intact hand task. We then measured the extent of coupling between the RSFC maps and motion-related activation maps. Dynamic changes of the coupling between the two fMRI maps were estimated using one-way repeated measures analysis of variance across the three stages. Moreover, imaging parameters were correlated with motor performances. Data analysis showed that there were different coupling patterns between motion-related activation and RSFC maps associating with the affected motor regions during the acute, subacute, and early chronic stages of stroke. Coupling strengths increased as the recovery from stroke progressed. Coupling strengths were correlated with hand motion performance in the acute stage, while coupling recovery was negatively correlated with the recovery

  14. Using transcranial magnetic stimulation of the undamaged brain to identify lesion sites that predict language outcome after stroke.

    Science.gov (United States)

    Lorca-Puls, Diego L; Gajardo-Vidal, Andrea; Seghier, Mohamed L; Leff, Alexander P; Sethi, Varun; Prejawa, Susan; Hope, Thomas M H; Devlin, Joseph T; Price, Cathy J

    2017-06-01

    unguided lesion overlap map; and (iii) a region identified from voxel-based lesion-symptom mapping. Finally, consistent with prior findings from functional imaging and transcranial magnetic stimulation in healthy participants, we show how damage to our transcranial magnetic stimulation-guided regions affected performance on phonologically more than semantically demanding tasks. The observation that phonological processing abilities were impaired years after the stroke, suggests that other brain regions were not able to fully compensate for the contribution that the transcranial magnetic stimulation-guided regions make to language tasks. More generally, our novel transcranial magnetic stimulation-guided lesion-deficit mapping approach shows how non-invasive stimulation of the healthy brain can be used to guide the identification of regions where brain damage is likely to cause persistent behavioural effects. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain.

  15. Penumbra pattern assessment in acute stroke patients: comparison of quantitative and non-quantitative methods in whole brain CT perfusion.

    Directory of Open Access Journals (Sweden)

    Kolja M Thierfelder

    Full Text Available BACKGROUND AND PURPOSE: While penumbra assessment has become an important part of the clinical decision making for acute stroke patients, there is a lack of studies measuring the reliability and reproducibility of defined assessment techniques in the clinical setting. Our aim was to determine reliability and reproducibility of different types of three-dimensional penumbra assessment methods in stroke patients who underwent whole brain CT perfusion imaging (WB-CTP. MATERIALS AND METHODS: We included 29 patients with a confirmed MCA infarction who underwent initial WB-CTP with a scan coverage of 100 mm in the z-axis. Two blinded and experienced readers assessed the flow-volume-mismatch twice and in two quantitative ways: Performing a volumetric mismatch analysis using OsiriX imaging software (MM(VOL and visual estimation of mismatch (MM(EST. Complementarily, the semiquantitative Alberta Stroke Programme Early CT Score for CT perfusion was used to define mismatch (MM(ASPECTS. A favorable penumbral pattern was defined by a mismatch of ≥ 30% in combination with a cerebral blood flow deficit of ≤ 90 ml and an MM(ASPECTS score of ≥ 1, respectively. Inter- and intrareader agreement was determined by Kappa-values and ICCs. RESULTS: Overall, MM(VOL showed considerably higher inter-/intrareader agreement (ICCs: 0.751/0.843 compared to MM(EST (0.292/0.749. In the subgroup of large (≥ 50 mL perfusion deficits, inter- and intrareader agreement of MM(VOL was excellent (ICCs: 0.961/0.942, while MM(EST interreader agreement was poor (0.415 and intrareader agreement was good (0.919. With respect to penumbra classification, MM(VOL showed the highest agreement (interreader agreement: 25 agreements/4 non-agreements/κ: 0.595; intrareader agreement 27/2/0.833, followed by MM(EST (22/7/0.471; 23/6/0.577, and MM(ASPECTS (18/11/0.133; 21/8/0.340. CONCLUSION: The evaluated approach of volumetric mismatch assessment is superior to pure visual and ASPECTS penumbra

  16. Modified constraint-induced therapy in acute stroke: a randomized controlled pilot study.

    Science.gov (United States)

    Page, Stephen J; Levine, Peter; Leonard, Anthony C

    2005-03-01

    To determine modified constraint-induced therapy (mCIT) feasibility and compare its efficacy to traditional rehabilitation (TR) in acute stroke patients exhibiting upper limb hemiparesis. Before-after, multiple baseline, randomized controlled pilot study. Rehabilitation hospital. Ten stroke patients Fugl-Meyer Assessment of Motor Recovery (Fugl-Meyer), Action Research Arm Test (ARA), and Motor Activity Log (MAL). Before intervention, all patients exhibited stable motor deficits and more affected arm nonuse. After intervention, mCIT patients displayed increased affected arm use (+ 2.43 on the MAL amount of use scale), uniformly exhibited increases on the Fugl-Meyer and ARA (mean change scores = + 18.7 and + 21.7, respectively), and were able to again perform valued activities. TR patients exhibited nominal change in affected limb use (+ 0.07 on the MAL amount of use scale) and modest changes on the Fugl-Meyer and ARA (+ 4.4 and + 4.8, respectively). Fugl-Meyer and ARA changes were significant for the mCIT group only (P < 0.01). mCIT is a promising regimen for improving more affected limb use and function in acute cerebrovascular accident. However, larger confirmatory studies need to be performed.

  17. Radiation-induced apoptosis and developmental disturbance of the brain

    International Nuclear Information System (INIS)

    Inouye, Minoru

    1995-01-01

    The developing mammalian brain is highly susceptible to ionizing radiation. A significant increase in small head size and mental retardation has been noted in prenatally exposed survivors of the atomic bombing, with the highest risk in those exposed during 8-15 weeks after fertilization. This stage corresponds to day 13 of pregnancy for mice and day 15 for rats in terms of brain development. The initial damage produced by radiation at this stage is cell death in the ventricular zone (VZ) of the brain mantle, the radiosensitive germinal cell population. During histogenesis of the cerebellum the external granular layer (EGL) is also radiosensitive. Although extensive cell death results in microcephaly and histological abnormlity, both VZ and EGL have an ability to recover from a considerable cell loss and form the normal structure of the central nervous system. The number of cell deaths to induce tissue abnormalities in adult brain rises in the range of 15-25% of the germinal cell population; and the threshold doses are about 0.3 Gy for cerebral defects and 1 Gy for cerebellar anomalies in both mice and rats. A similar threshold level is suggested in human cases in induction of mental retardation. Radiation-induced cell death in the VZ and EGL has been revealed as apoptosis, by the nuclear and cytoplasmic condensation, transglutaminase activation, required macromolecular synthesis, and internucleosomal DNA cleavage. Apoptosis of the germinal cell is assumed to eliminate acquired genetic damage. Once an abnormality in DNA has been induced and fixed in a germinal cell, it would be greatly amplified during future proliferation. These cells would commit suicide when injured for replacement by healthy cells, rather than undertake DNA repair. In fact they show very slow repair of cellular damage. Thus the high sensitivity of undifferentiated neural cells to the lethal effect of radiation may constitute a biological defense mechanism. (author) 69 refs

  18. Bobath Concept versus constraint-induced movement therapy to improve arm functional recovery in stroke patients: a randomized controlled trial.

    Science.gov (United States)

    Huseyinsinoglu, Burcu Ersoz; Ozdincler, Arzu Razak; Krespi, Yakup

    2012-08-01

    To compare the effects of the Bobath Concept and constraint-induced movement therapy on arm functional recovery among stroke patients with a high level of function on the affected side. A single-blinded, randomized controlled trial. Outpatient physiotherapy department of a stroke unit. A total of 24 patients were randomized to constraint-induced movement therapy or Bobath Concept group. The Bobath Concept group was treated for 1 hour whereas the constraint-induced movement therapy group received training for 3 hours per day during 10 consecutive weekdays. Main measures were the Motor Activity Log-28, the Wolf Motor Function Test, the Motor Evaluation Scale for Arm in Stroke Patients and the Functional Independence Measure. The two groups were found to be homogeneous based on demographic variables and baseline measurements. Significant improvements were seen after treatment only in the 'Amount of use' and 'Quality of movement' subscales of the Motor Activity Log-28 in the constraint-induced movement therapy group over the the Bobath Concept group (P = 0.003; P = 0.01 respectively). There were no significant differences in Wolf Motor Function Test 'Functional ability' (P = 0.137) and 'Performance time' (P = 0.922), Motor Evaluation Scale for Arm in Stroke Patients (P = 0.947) and Functional Independence Measure scores (P = 0.259) between the two intervention groups. Constraint-induced movement therapy and the Bobath Concept have similar efficiencies in improving functional ability, speed and quality of movement in the paretic arm among stroke patients with a high level of function. Constraint-induced movement therapy seems to be slightly more efficient than the Bobath Concept in improving the amount and quality of affected arm use.

  19. Baicalin Attenuates Blood-Brain Barrier Disruption and Hemorrhagic Transformation and Improves Neurological Outcome in Ischemic Stroke Rats with Delayed t-PA Treatment: Involvement of ONOO--MMP-9 Pathway.

    Science.gov (United States)

    Chen, Hansen; Guan, Binghe; Chen, Xi; Chen, Xingmiao; Li, Caiming; Qiu, Jinhua; Yang, Dan; Liu, Ke Jian; Qi, Suhua; Shen, Jiangang

    2017-12-23

    Tissue plasminogen activator (t-PA) has a restrictive therapeutic window within 4.5 h after ischemic stroke with the risk of hemorrhagic transformation (HT) and neurotoxicity when it is used beyond the time window. In the present study, we tested the hypothesis that baicalin, an active compound of medicinal plant, could attenuate HT in cerebral ischemia stroke with delayed t-PA treatment. Male Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 4.5 h and then continuously received t-PA infusion (10 mg/kg) for 0.5 h and followed by 19-h reperfusion. Baicalin (50, 100, 150 mg/kg) was administrated via femoral vein at 4.5 h after MCAO cerebral ischemia. Delayed t-PA infusion significantly increased the mortality rate, induced HT, blood-brain barrier (BBB) damage, and apoptotic cell death in the ischemic brains and exacerbated neurological outcomes in cerebral ischemia-reperfusion rats at 24 h after MCAO cerebral ischemia. Co-treatment of baicalin significantly reduced the mortality rates, ameliorated the t-PA-mediated BBB disruption and HT. Furthermore, baicalin showed to directly scavenge peroxynitrite and inhibit MMP-9 expression and activity in the ischemic brains with the delayed t-PA treatment. Baicalin had no effect on the t-PA fibrinolytic function indicated by t-PA activity assay. Taken together, baicalin could attenuate t-PA-mediated HT and improve the outcomes of ischemic stroke treatment possibly via inhibiting peroxynitrite-mediated MMP-9 activation.

  20. Early time course of N-acetylaspartate, creatine and phosphocreatine, and compounds containing choline in the brain after acute stroke. A proton magnetic resonance spectroscopy study

    DEFF Research Database (Denmark)

    Gideon, P; Henriksen, O; Sperling, B

    1992-01-01

    BACKGROUND AND PURPOSE: The early time course after acute stroke of cerebral N-acetylaspartate, creatine and phosphocreatine, and compounds containing choline was studied in vivo by means of localized water-suppressed proton magnetic resonance spectroscopy. METHODS: Eight patients with acute stroke...... were studied serially in the acute phase, 1 week after, and 2-4 weeks after the onset of clinical symptoms. Ten healthy volunteers served as controls. A stimulated echo (STEAM) sequence was used for measurement of the brain metabolites in a volume of interest located within the infarcted area...

  1. What You Need to Know about Stroke

    Science.gov (United States)

    ... the brain. The other kind of stroke, called hemorrhagic stroke, is caused by a blood vessel that breaks ... are very common among African Americans. The best treatment for stroke is prevention. You can reduce your ...

  2. What Are the Warning Signs of Stroke?

    Science.gov (United States)

    ... Cardiovascular Conditions What Are the Warning Signs of Stroke? Brain tissue affected by blockage Stroke is the fifth leading cause of death in ... over 55 years old have more chance of stroke, and the risk gets greater as you get ...

  3. Bevacizumab alleviates radiation-induced brain necrosis: A report of four cases

    Directory of Open Access Journals (Sweden)

    Li Xiang-Pan

    2015-01-01

    Full Text Available To analyze the therapeutic effect of bevacizumab on radiation-induced brain necrosis. Four radiation-induced brain necrosis patients, administered with bevacizumab at a dose of 7.5 mg/kg every 3 weeks, 2 times. One case of brain metastasis of lung cancer and one case of nasopharyngeal carcinoma with brain necrosis after radiotherapy. However, their physical signs disappeared after the treatment with bevacizumab. One case of brainstem lesion and one case of brain glioma patient showed a transient improvement in signs and symptoms after treatment with bevacizumab. Bevacizumab can significantly alleviate the radiation-induced brain edema, and can improve the symptoms successively.

  4. Brain lesion induced by 1319nm laser radiation

    Science.gov (United States)

    Yang, Zaifu; Chen, Hongxia; Wang, Jiarui; Chen, Peng; Ma, Ping; Qian, Huanwen

    2010-11-01

    The laser-tissue interaction has not been well defined at the 1319 nm wavelength for brain exposure. The goal of this research effort was to identify the behavioral and histological changes of brain lesion induced by 1319 nm laser. The experiment was performed on China Kunming mice. Unilateral brain lesions were created with a continuous-wave Nd:YAG laser (1319nm). The brain lesions were identified through behavioral observation and histological haematoxylin and eosin (H&E) staining method. The behavior change was observed for a radiant exposure range of 97~773 J/cm2. The histology of the recovery process was identified for radiant exposure of 580 J/cm2. Subjects were sacrificed 1 hour, 1 week, 2 weeks, 3 months, 7 months and 13 months after laser irradiation. Results showed that after laser exposure, behavioral deficits, including kyphosis, tail entasia, or whole body paralysis could be noted right after the animals recovered from anesthesia while gradually disappeared within several days and never recurred again. Histologically, the laser lesion showed a typical architecture dependent on the interval following laser treatment. The central zone of coagulation necrosis is not apparent right after exposure but becomes obvious within several days. The nerotic tissue though may persist for a long time, will finally be completely resorbed. No carbonization granules formed under our exposure condition.

  5. Default Mode Network Connectivity in Stroke Patients.

    Science.gov (United States)

    Tuladhar, Anil Man; Snaphaan, Liselore; Shumskaya, Elena; Rijpkema, Mark; Fernandez, Guillén; Norris, David G; de Leeuw, Frank-Erik

    2013-01-01

    The pathophysiology of episodic memory dysfunction after infarction is not completely understood. It has been suggested that infarctions located anywhere in the brain can induce widespread effects causing disruption of functional networks of the cortical regions. The default mode network, which includes the medial temporal lobe, is a functional network that is associated with episodic memory processing. We investigated whether the default mode network activity is reduced in stroke patients compared to healthy control subjects in the resting state condition. We assessed the whole brain network properties during resting state functional MRI in 21 control subjects and 20 'first-ever' stroke patients. Patients were scanned 9-12 weeks after stroke onset. Stroke lesions were located in various parts of the brain. Independent component analyses were conducted to identify the default mode network and to compare the group differences of the default mode network. Furthermore, region-of-interest based analysis was performed to explore the functional connectivity between the regions of the default mode network. Stroke patients performed significantly worse than control subjects on the delayed recall score on California verbal learning test. We found decreased functional connectivity in the left medial temporal lobe, posterior cingulate and medial prefrontal cortical areas within the default mode network and reduced functional connectivity between these regions in stroke patients compared with controls. There were no significant volumetric differences between the groups. These results demonstrate that connectivity within the default mode network is reduced in 'first-ever' stroke patients compared to control subjects. This phenomenon might explain the occurrence of post-stroke cognitive dysfunction in stroke patients.

  6. A review of Constraint-Induced Therapy applied to aphasia rehabilitation in stroke patients

    Directory of Open Access Journals (Sweden)

    Joana Bisol Balardin

    Full Text Available Abstract Constraint-induced aphasia therapy (CIAT is an intensive therapy model based on the forced use of verbal oral language as the sole channel of communication, while any alternative communication mode such as writing, gesturing or pointing are prevented. Objectives: This critical review involved the analysis of studies examining CIAT applied to stroke patients. Methods and Results: Using keywords, the Medline database was searched for relevant studies published between 2001 and 2008 (Medline 2001-2008. The critical evaluation of the articles was based on the classifications described by the ASNS (Cicerone adaptation. Two studies were categorized as level Ia, two as level II and one study as level IV. Conclusions: These recommendations should be interpreted with caution, given the small number of studies involved, but serve as a guideline for future studies in aphasia therapy.

  7. Anabolic steroids abuse-induced cardiomyopathy and ischaemic stroke in a young male patient.

    Science.gov (United States)

    Shamloul, Reham Mohammed; Aborayah, Ahmed Fathy; Hashad, Assem; Abd-Allah, Foad

    2014-02-26

    We report a case of a 37-year-old man presented with acute stroke and hepatorenal impairment which were associated with anabolic-androgenic steroids (AAS) abuse over 2 years. Despite the absence of apparent symptoms and signs of congestive heart failure at presentation, an AAS-induced dilated cardiomyopathy with multiple thrombi in the left ventricle was attributed to be the underlying cause of his condition. Awareness of the complications of AAS led to the prompt treatment of the initially unrecognised dilated cardiomyopathy, and improved the liver and kidney functions. However, the patient was exposed to a second severe ischaemic event, which led to his death. This unique and complex presentation of AAS complications opens for better recognition and treatment of their potentially fatal effects.

  8. The Role of Endogenous Neurogenesis in Functional Recovery and Motor Map Reorganization Induced by Rehabilitative Therapy after Stroke in Rats.

    Science.gov (United States)

    Shiromoto, Takashi; Okabe, Naohiko; Lu, Feng; Maruyama-Nakamura, Emi; Himi, Naoyuki; Narita, Kazuhiko; Yagita, Yoshiki; Kimura, Kazumi; Miyamoto, Osamu

    2017-02-01

    Endogenous neurogenesis is associated with functional recovery after stroke, but the roles it plays in such recovery processes are unknown. This study aims to clarify the roles of endogenous neurogenesis in functional recovery and motor map reorganization induced by rehabilitative therapy after stroke by using a rat model of cerebral ischemia (CI). Ischemia was induced via photothrombosis in the caudal forelimb area of the rat cortex. First, we examined the effect of rehabilitative therapy on functional recovery and motor map reorganization, using the skilled forelimb reaching test and intracortical microstimulation. Next, using the same approaches, we examined how motor map reorganization changed when endogenous neurogenesis after stroke was inhibited by cytosine-β-d-arabinofuranoside (Ara-C). Rehabilitative therapy for 4 weeks after the induction of stroke significantly improved functional recovery and expanded the rostral forelimb area (RFA). Intraventricular Ara-C administration for 4-10 days after stroke significantly suppressed endogenous neurogenesis compared to vehicle, but did not appear to influence non-neural cells (e.g., microglia, astrocytes, and vascular endothelial cells). Suppressing endogenous neurogenesis via Ara-C administration significantly inhibited (~50% less than vehicle) functional recovery and RFA expansion (~33% of vehicle) induced by rehabilitative therapy after CI. After CI, inhibition of endogenous neurogenesis suppressed both the functional and anatomical markers of rehabilitative therapy. These results suggest that endogenous neurogenesis contributes to functional recovery after CI related to rehabilitative therapy, possibly through its promotion of motor map reorganization, although other additional roles cannot be ruled out. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  9. A Lesion-Proof Brain? Multidimensional Sensorimotor, Cognitive, and Socio-Affective Preservation Despite Extensive Damage in a Stroke Patient.

    Science.gov (United States)

    García, Adolfo M; Sedeño, Lucas; Herrera Murcia, Eduar; Couto, Blas; Ibáñez, Agustín

    2016-01-01

    In this study, we report an unusual case of mutidimensional sensorimotor, cognitive, and socio-affective preservation in an adult with extensive, acquired bilateral brain damage. At age 43, patient CG sustained a cerebral hemorrhage and a few months later, she suffered a second (ischemic) stroke. As a result, she exhibited extensive damage of the right hemisphere (including frontal, temporal, parietal, and occipital regions), left Sylvian and striatal areas, bilateral portions of the insula and the amygdala, and the splenium. However, against all probability, she was unimpaired across a host of cognitive domains, including executive functions, attention, memory, language, sensory perception (e.g., taste recognition and intensity discrimination), emotional processing (e.g., experiencing of positive and negative emotions), and social cognition skills (prosody recognition, theory of mind, facial emotion recognition, and emotional evaluation). Her functional integrity was further confirmed through neurological examination and contextualized observation of her performance in real-life tasks. In sum, CG's case resists straightforward classifications, as the extent and distribution of her lesions would typically produce pervasive, multidimensional deficits. We discuss the rarity of this patient against the backdrop of other reports of atypical cognitive preservation, expound the limitations of several potential accounts, and highlight the challenges that the case poses for current theories of brain organization and resilience.

  10. Syntactic and Morphosyntactic Processing in Stroke-Induced and Primary Progressive Aphasia

    Directory of Open Access Journals (Sweden)

    Cynthia K. Thompson

    2013-01-01

    Full Text Available The paper reports findings derived from three experiments examining syntactic and morphosyntactic processing in individuals with agrammatic and logopenic variants of primary progressive aphasia (PPA-G and PPA-L, respectively and stroke-induced agrammatic and anomic aphasia (StrAg and StrAn, respectively. We examined comprehension and production of canonical and noncanonical sentence structures and production of tensed and nontensed verb forms using constrained tasks in experiments 1 and 2, using the Northwestern Assessment of Verbs and Sentences (NAVS [57] and the Northwestern Assessment of Verb Inflection (NAVI, Thompson and Lee, experimental version test batteries, respectively. Experiment 3 examined free narrative samples, focusing on syntactic and morphosyntactic measures, i.e. production of grammatical sentences, noun to verb ratio, open-class to closed-class word production ratio, and the production of correctly inflected verbs. Results indicate that the two agrammatic groups (i.e., PPA-G and StrAg pattern alike on syntactic and morphosyntactic measures, showing more impaired noncanonical compared to canonical sentence comprehension and production and greater difficulties producing tensed compared to nontensed verb forms. Their spontaneous speech also contained significantly fewer grammatical sentences and correctly inflected verbs, and they produced a greater proportion of nouns compared to verbs, than healthy speakers. In contrast, PPA-L and StrAn individuals did not display these deficits, and performed significantly better than the agrammatic groups on these measures. The findings suggest that agrammatism, whether induced by degenerative disease or stroke, is associated with characteristic deficits in syntactic and morphosyntactic processing. We therefore recommend that linguistically sophisticated tests and narrative analysis procedures be used to systematically evaluate the linguistic ability of individuals with PPA, contributing to

  11. GSK-3 as a Target for Lithium-induced Neuroprotection against Excitotoxicity in Neuronal Cultures and Animal Models of Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    De-Maw eChuang

    2011-08-01

    Full Text Available The mood stabilizer lithium inhibits glycogen synthase kinase-3 (GSK-3 directly or indirectly by enhancing serine phosphorylation of both alpha and beta isoforms. Lithium robustly protected primary brain neurons from glutamate-induced excitotoxicity; these actions were mimicked by other GSK-3 inhibitors or silencing/inhibiting GSK-3alpha and/or beta isoforms. Lithium rapidly activated Akt to enhance GSK-3 serine phosphorylation and to block glutamate-induced Akt inactivation. Lithium also upregulated Bcl-2 and suppressed glutamate-induced p53 and Bax. Induction of BDNF was required for lithium’s neuroprotection to occur. BDNF promoter IV was activated by GSK-3 inhibition using lithium or other drugs, or through gene silencing/inactivation of either isoform. Further, lithium’s neuroprotective effects were associated with inhibition of NMDA receptor-mediated calcium influx and downstream signaling. In rodent ischemic models, post-insult treatment with lithium decreased infarct volume, ameliorated neurological deficits and improved functional recovery. Upregulation of heat shock protein 70 (HSP70 and Bcl-2 as well as downregulation of p53 likely contributed to lithium’s protective effects. Delayed treatment with lithium improved functional MRI responses, which was accompanied by enhanced angiogenesis. Two GSK-3-regulated pro-angiogenic factors, matrix metalloproteinase-9 (MMP-9 and vascular endothelial growth factor were induced by lithium. Finally, lithium promoted migration of mesenchymal stem cells (MSCs by upregulation of MMP-9 through GSK-3beta inhibition. Notably, transplantation of lithium-primed MSCs into ischemic rats enhanced MSC migration to the injured brain regions and improved the neurological performance. Several other GSK-3 inhibitors have also been reported to be beneficial in rodent ischemic models. Together, GSK-3 inhibition is a rational strategy to combat ischemic stroke and other excitotoxicity-related brain disorders.

  12. Motor rehabilitation after traumatic brain injury and stroke - Advances in assessment and therapy.

    Science.gov (United States)

    Platz, Thomas; Hesse, S.; Mauritz, K.-H.

    1999-01-01

    A long-term goal in motor rehabilitation is that treatment is not selected on the basis of 'schools of thought', but rather, based on knowledge about efficacy and effectiveness of specific interventions for specific situations (e.g. functional syndromes). Motor dysfunction after stroke or TBI can be caused by many different functional syndromes such as paresis, ataxia, deafferentaion, visuo-perceptual deficits, or apraxia. Examples are provided showing that theory-based analysis of motor behavior makes it possible to describe 'syndrome-specific motor deficits'. Its potential implications for motor rehabilitation are that our understanding of altered motor behavior as well as specific therapeutic approaches might be promoted. A methodological prerequisite for clinical trials in rehabilitation is knowledge about test properties of assessment tools in follow-up situations such as test-retest reliability and responsiveness to change. Test-retest reliability assesses whether a test can produce stable measures with test repetition, while sensitivity to change reflects whether a test detects changes that occur over time. Exemplifying these considerations, a reliability and validity study of a kinematic arm movement analysis is summarized. In terms of new therapeutic developments, two examples of clinical therapeutic studies are provided assessing the efficacy of specific inter-ventions for specific situations in arm and gait rehabilitation: the Arm Ability Training for high functioning hemiparetic stroke and TBI patients, and the treadmill training for non-ambulatory hemiparetic patients. In addition, a new technical development, a machine-controlled gait trainer ist introduced.

  13. LSD-induced entropic brain activity predicts subsequent personality change.

    Science.gov (United States)

    Lebedev, A V; Kaelen, M; Lövdén, M; Nilsson, J; Feilding, A; Nutt, D J; Carhart-Harris, R L

    2016-09-01

    Personality is known to be relatively stable throughout adulthood. Nevertheless, it has been shown that major life events with high personal significance, including experiences engendered by psychedelic drugs, can have an enduring impact on some core facets of personality. In the present, balanced-order, placebo-controlled study, we investigated biological predictors of post-lysergic acid diethylamide (LSD) changes in personality. Nineteen healthy adults underwent resting state functional MRI scans under LSD (75µg, I.V.) and placebo (saline I.V.). The Revised NEO Personality Inventory (NEO-PI-R) was completed at screening and 2 weeks after LSD/placebo. Scanning sessions consisted of three 7.5-min eyes-closed resting-state scans, one of which involved music listening. A standardized preprocessing pipeline was used to extract measures of sample entropy, which characterizes the predictability of an fMRI time-series. Mixed-effects models were used to evaluate drug-induced shifts in brain entropy and their relationship with the observed increases in the personality trait openness at the 2-week follow-up. Overall, LSD had a pronounced global effect on brain entropy, increasing it in both sensory and hierarchically higher networks across multiple time scales. These shifts predicted enduring increases in trait openness. Moreover, the predictive power of the entropy increases was greatest for the music-listening scans and when "ego-dissolution" was reported during the acute experience. These results shed new light on how LSD-induced shifts in brain dynamics and concomitant subjective experience can be predictive of lasting changes in personality. Hum Brain Mapp 37:3203-3213, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. Effects of glycyrrhizin pre-treatment on transient ischemic brain ...

    African Journals Online (AJOL)

    Effects of glycyrrhizin pre-treatment on transient ischemic brain injury in mice. ... on transient ischemic brain injury in mice. Chiyeon Lim, Sehyun Lim, Young-Jun Lee, Bokcheul Kong, Byoungho Lee, Chang-Hyun Kim, Buyeo Kim, Suin Cho ... induced brain damage. Keywords: Glycyrrhizin, licorice, stroke, apoptosis ...

  15. Peripheral nerve injury induces adult brain neurogenesis and remodelling.

    Science.gov (United States)

    Rusanescu, Gabriel; Mao, Jianren

    2017-02-01

    Unilateral peripheral nerve chronic constriction injury (CCI) has been widely used as a research model of human neuropathic pain. Recently, CCI has been shown to induce spinal cord adult neurogenesis, which may contribute to the chronic increase in nociceptive sensitivity. Here, we show that CCI also induces rapid and profound asymmetrical anatomical rearrangements in the adult rodent cerebellum and pons. This remodelling occurs throughout the hindbrain, and in addition to regions involved in pain processing, also affects other sensory modalities. We demonstrate that these anatomical changes, partially reversible in the long term, result from adult neurogenesis. Neurogenic markers Mash1, Ngn2, doublecortin and Notch3 are widely expressed in the rodent cerebellum and pons, both under normal and injured conditions. CCI-induced hindbrain structural plasticity is absent in Notch3 knockout mice, a strain with impaired neuronal differentiation, demonstrating its dependence on adult neurogenesis. Grey matter and white matter structural changes in human brain, as a result of pain, injury or learned behaviours have been previously detected using non-invasive neuroimaging techniques. Because neurogenesis-mediated structural plasticity is thought to be restricted to the hippocampus and the subventricular zone, such anatomical rearrangements in other parts of the brain have been thought to result from neuronal plasticity or glial hypertrophy. Our findings suggest the presence of extensive neurogenesis-based structural plasticity in the adult mammalian brain, which may maintain a memory of basal sensory levels, and act as an adaptive mechanism to changes in sensory inputs. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  16. [Brain repair after ischemic stroke: role of neurotransmitters in post-ischemic neurogenesis].

    Science.gov (United States)

    Sánchez-Mendoza, Eduardo; Bellver-Landete, Víctor; González, María Pilar; Merino, José Joaquín; Martínez-Murillo, Ricardo; Oset-Gasque, María Jesús

    2012-11-01

    Brain ischemia and reperfusion produce alterations in the microenvironment of the parenchyma, including ATP depletion, ionic homeostasis alterations, inflammation, release of multiple cytokines and abnormal release of neurotransmitters. As a consequence, the induction of proliferation and migration of neural stem cells towards the peri-infarct region occurs. The success of new neurorestorative treatments for damaged brain implies the need to know, with greater accuracy, the mechanisms in charge of regulating adult neurogenesis, both under physiological and pathological conditions. Recent evidence demonstrates that many neurotransmitters, glutamate in particular, control the subventricular zone, thus being part of the complex signalling network that influences the production of new neurons. Neurotransmitters provide a link between brain activity and subventricular zone neurogenesis. Therefore, a deeper knowledge of the role of neurotransmitters systems, such as glutamate and its transporters, in adult neurogenesis, may provide a valuable tool to be used as a neurorestorative therapy in this pathology.

  17. Effects of neurofeedback training with an electroencephalogram-based brain-computer interface for hand paralysis in patients with chronic stroke: a preliminary case series study.

    Science.gov (United States)

    Shindo, Keiichiro; Kawashima, Kimiko; Ushiba, Junichi; Ota, Naoki; Ito, Mari; Ota, Tetsuo; Kimura, Akio; Liu, Meigen

    2011-10-01

    To explore the effectiveness of neurorehabilitative training using an electroencephalogram-based brain- computer interface for hand paralysis following stroke. A case series study. Eight outpatients with chronic stroke demonstrating moderate to severe hemiparesis. Based on analysis of volitionally decreased amplitudes of sensory motor rhythm during motor imagery involving extending the affected fingers, real-time visual feedback was provided. After successful motor imagery, a mechanical orthosis partially extended the fingers. Brain-computer interface interventions were carried out once or twice a week for a period of 4-7 months, and clinical and neurophysiological examinations pre- and post-intervention were compared. New voluntary electromyographic activity was measured in the affected finger extensors in 4 cases who had little or no muscle activity before the training, and the other participants exhibited improvement in finger function. Significantly greater suppression of the sensory motor rhythm over both hemispheres was observed during motor imagery. Transcranial magnetic stimulation showed increased cortical excitability in the damaged hemisphere. Success rates of brain-computer interface training tended to increase as the session progressed in 4 cases. Brain-computer interface training appears to have yielded some improvement in motor function and brain plasticity. Further controlled research is needed to clarify the role of the brain-computer interface system.

  18. Impact of Low-Level Thyroid Hormone Disruption Induced by Propylthiouracil on Brain Development and Function.*

    Science.gov (United States)

    The critical role of thyroid hormone (TH) in brain development is well established, severe deficiencies leading to significant neurological dysfunction. Much less information is available on more modest perturbations of TH on brain function. The present study induced varying degr...

  19. B vitamins and magnetic resonance imaging-detected ischemic brain lesions in patients with recent transient ischemic attack or stroke: the VITAmins TO Prevent Stroke (VITATOPS) MRI-substudy.

    Science.gov (United States)

    Cavalieri, Margherita; Schmidt, Reinhold; Chen, Christopher; Mok, Vincent; de Freitas, Gabriel R; Song, Swithin; Yi, Qilong; Ropele, Stefan; Grazer, Anja; Homayoon, Nina; Enzinger, Christian; Loh, Katherine; Wong, Ka Sing Lawrence; Wong, Adrian; Xiong, Yunyun; Chang, Hui Meng; Wong, Meng Cheong; Fazekas, Franz; Eikelboom, John W; Hankey, Graeme J

    2012-12-01

    Elevated concentrations of homocysteine are associated with cerebral small vessel disease (CSVD). B-vitamin supplementation with folate and vitamins B12 and B6 reduces homocysteine concentrations. In a substudy of the VITAmins TO Prevent Stroke (VITATOPS) trial, we assessed the hypothesis that the addition of once-daily supplements of B vitamins would reduce the progression of CSVD-related brain lesions. A total of 359 patients with recent stroke or transient ischemic attack, who were randomly allocated to double-blind treatment with placebo or b vitamins, underwent brain MRI at randomization and after 2 years of B-vitamin supplementation. MR images were analyzed blinded to treatment allocation. Outcomes related to the prespecified hypothesis were progression of white matter hyperintensities and incident lacunes. We also explored the effect of B-vitamin supplementation on the incidence of other ischemic abnormalities. After 2 years of treatment with b vitamins or placebo, there was no significant difference in white matter hyperintensities volume change (0.08 vs 0.13 cm3; P=0.419) and incidence of lacunes (8.0% vs 5.9%, P=0.434; odds ratio=1.38). In a subanalysis of patients with MRI evidence of severe CSVD at baseline, b-vitamin supplementation was associated with a significant reduction in white matter hyperintensities volume change (0.3 vs 1.7 cm3; P=0.039). Daily B-vitamin supplementation for 2 years did not significantly reduce the progression of brain lesions resulting from presumed CSVD in all patients with recent stroke or transient ischemic attack but may do so in the subgroup of patients with recent stroke or transient ischemic attack and severe CSVD. http://vitatops.highway1.com.au/. Unique identifier: NCT00097669 and ISRCTN74743444.

  20. Therapy-Induced Neuroplasticity of Language in Chronic Post Stroke Aphasia: A Mismatch Negativity Study of (A)Grammatical and Meaningful/less Mini-Constructions

    Science.gov (United States)

    Lucchese, Guglielmo; Pulvermüller, Friedemann; Stahl, Benjamin; Dreyer, Felix R.; Mohr, Bettina

    2017-01-01

    Clinical language performance and neurophysiological correlates of language processing were measured before and after intensive language therapy in patients with chronic (time post stroke >1 year) post stroke aphasia (PSA). As event-related potential (ERP) measure, the mismatch negativity (MMN) was recorded in a distracted oddball paradigm to short spoken sentences. Critical ‘deviant’ sentence stimuli where either well-formed and meaningful, or syntactically, or lexico-semantically incorrect. After 4 weeks of speech-language therapy (SLT) delivered with high intensity (10.5 h per week), clinical language assessment with the Aachen Aphasia Test battery demonstrated significant linguistic improvements, which were accompanied by enhanced MMN responses. More specifically, MMN amplitudes to grammatically correct and meaningful mini-constructions and to ‘jabberwocky’ sentences containing a pseudoword significantly increased after therapy. However, no therapy-related changes in MMN responses to syntactically incorrect strings including agreement violations were observed. While MMN increases to well-formed meaningful strings can be explained both at the word and construction levels, the neuroplastic change seen for ‘jabberwocky’ sentences suggests an explanation in terms of constructions. The results confirm previous reports that intensive SLT leads to improvements of linguistic skills in chronic aphasia patients and now demonstrate that this clinical improvement is associated with enhanced automatic brain indexes of construction processing, although no comparable change is present for ungrammatical strings. Furthermore, the data confirm that the language-induced MMN is a useful tool to map functional language recovery in PSA. PMID:28111545

  1. Perfusion measurements of the brain: using dynamic CT for the quantitative assessment of cerebral ischemia in acute stroke

    International Nuclear Information System (INIS)

    Klotz, Ernst; Koenig, Matthias

    1999-01-01

    Objective: Perfusion CT has been successfully used as a functional imaging technique for the differential diagnosis of patients with hyperacute stroke. We investigated to what extent this technique can also be used for the quantitative assessment of cerebral ischemia. Methods and material: We studied linearity, spatial resolution and noise behaviour of cerebral blood flow (CBF) determination with computer simulations and phantom measurements. Statistical ROI based analysis of CBF images of a subset of 38 patients from a controlled clinical stroke study with currently more than 75 patients was done to check the power of relative cerebral blood flow (rCBF) values to predict definite infarction and ischemic penumbra. Classification was performed using follow-up CT and MR data. Results: Absolute CBF values were systematically underestimated, the degree depended on the cardiac output of the patients. Phantom measurements and simulations indicated very good linearity allowing reliable calculation of rCBF values. Infarct and penumbra areas in 19 patients receiving standard heparin therapy had mean rCBF values of 0.19 and 0.62, respectively. The corresponding values for 19 patients receiving local intraarterial fibrinolysis were 0.18 and 0.57. The difference between infarct and penumbra values was highly significant (P<0.0001) in both groups. No penumbra area was found with an rCBF value of less than 0.20. While in the heparin group only 25% of all areas with an rCBF between 0.20 and 0.35 survived, in the fibrinolytic group 61% of these areas could be saved (P<0.05). Conclusion: Perfusion CT is a fast and practical technique for routine clinical application. It provides substantial and important additional information for the selection of the optimal treatment strategy for patients with hyperacute stroke. Relative values of cerebral blood flow discriminate very well between areas of reversible and irreversible ischemia; an rCBF value of 0.20 appears to be a definite lower

  2. Effect of Fluoxetine on Expression of Brain-derived Neurotrophic Factor in Patients with Post-stroke Depression

    Directory of Open Access Journals (Sweden)

    DING Zhaosheng

    2014-12-01

    Full Text Available Objective: To observe the effect of Fluoxetine on the expression brain-derived neurotrophic factor (BDNF in patients with post-stroke depression (PSD. Methods: A total of 62 patients with ischemic stroke and post depression were divided into PSD group (32 cases given fluoxetine combined with rehabilitation and Non-PSD group (30 cases given rehabilitation treatment according to the presence of depression after stroke. The degree of depression, activities of daily living and the motor function were evaluated by Hamilton Depression Scale 17 (HAMD-17, Modified Barthel Index (MBI and Fugl-Meyer Assessment (FMA before and after treatment, respectively. And the levels of BDNF were examined using enzyme-linked immunosorbent assay (ELISA. Results: Before treatment, HAMD-17 score and MBI scores were markedly higher in PSD group than in Non-PSD group (P<0.05 or P<0.01. Compared with treatment before, HAMD-17 score decreased significantly, while FMA score increased markedly in PSD group after 3, 6 and 12-month treatment, and MBI score increased from the first-month treatment, and increased along with the time (P<0.05,P<0.01. In Non-PSD group, MBI and FMA scores increased from 1-month treatment and along with the time (P<0.05,P<0.01. Comparison between two groups showed that 12 months after treatment, there were no significant differences in HAMD-17, MBI and FMA scores (P>0.05. After 3, 6 and 12-month treatment, BDNF concentrations in PSD group were significantly higher than in Non-PSD group (P<0.01. Relevant analysis showed that BDNF in patients with PSD was in negative relationship with HAMD-17 (r=-0.784, P=0.000 and in positive association with BMI and FMA (r=0.761, P=0.000; r=0.789, P=0.000. Conclusion: Fluoxetine combined with rehabilitation can regulate depression, improve motor function and activities of daily living through increasing the concentration of BNDF in treating PSD patients.

  3. Efficient neuroplasticity induction in chronic stroke patients by an associative brain-computer interface

    DEFF Research Database (Denmark)

    Mrachacz-Kersting, Natalie; Jiang, Ning; Stevenson, Andrew James Thomas

    2016-01-01

    Brain-computer interfaces (BCIs) have the potential to improve functionality in chronic stoke patients when applied over a large number of sessions. Here, we evaluate the effect and the underlying mechanisms of three BCI training sessions in a double-blind-sham-controlled design. The applied BCI ...

  4. Bacoside A: Role in Cigarette Smoking Induced Changes in Brain

    Directory of Open Access Journals (Sweden)

    G. Vani

    2015-01-01

    Full Text Available Cigarette smoking (CS is a major health hazard that exerts diverse physiologic and biochemical effects mediated by the components present and generated during smoking. Recent experimental studies have shown predisposition to several biological consequences from both active and passive cigarette smoke exposure. In particular, passive smoking is linked to a number of adverse health effects which are equally harmful as active smoking. A pragmatic approach should be considered for designing a pharmacological intervention to combat the adverse effects of passive smoking. This review describes the results from a controlled experimental condition, testing the effect of bacoside A (BA on the causal role of passive/secondhand smoke exposure that caused pathological and neurological changes in rat brain. Chronic exposure to cigarette smoke induced significant changes in rat brain histologically and at the neurotransmitter level, lipid peroxidation states, mitochondrial functions, membrane alterations, and apoptotic damage in rat brain. Bacoside A is a neuroactive agent isolated from Bacopa monnieri. As a neuroactive agent, BA was effective in combating these changes. Future research should examine the effects of BA at molecular level and assess its functional effects on neurobiological and behavioral processes associated with passive smoke.

  5. On the influence of space storms on the frequency of infarct-myocardial, brain strokes, and hard car accidents; possible using of CR for their forecasting

    Science.gov (United States)

    Dorman, L. I.; Iucci, N.; Ptitsyna, N. G.; Villoresi, G.

    We consider the influence of space storms as strong interplanetary shock waves causing great cosmic ray Forbush-decreases and big geomagnetic storms on the people health at the ground level We used data of more than 7 millions ambulance cases in Moscow and St Petersburg included information on daily numbers of the hard traffic accidents infarctions and brain strokes We found that during space storms the average daily numbers of hard traffic accidents with using ambulances as well as infarctions and brain strokes confirmed by medical personal increase by 17 4 pm 3 1 10 5 pm 1 2 and 7 0 pm 1 7 respectively We show that the forecasting of these dangerous apace phenomena can be done partly by using cosmic ray data on pre-increase and pre-decrease effects as well as on the change of 3-D cosmic ray anisotropy

  6. Differentiation of density of ischaemic brain tissue in computed tomography with respect to neurological deficit in acute and subacute period of ischaemic stroke

    International Nuclear Information System (INIS)

    Sobotko-Waszczeniuk, O.; Lukasiewicz, A.; Janica, J.; Lebkowska, U.; Pyd, E.

    2009-01-01

    Background: The detection of ischaemic brain tissue by a CT depends on degree and time of hypoperfusion. The aim of the present study was to establish interrelation between morphologic changes in CT scans and clinical classification of focal neurological deficit. Material/Methods: We analyzed data from 139 consecutive patients enrolled in a prospective cohort study at Clinic of Neurology University Hospital in Bialystok, at which emergency CT for patients suspected of having acute (>6 h) ischaemic stroke was performed. Next follow up nonenhanced CT scans were obtained between 7 and 10 day after admission. Results: In general, the presence of an ischaemic hypo density in a patient with signs and symptoms of acute stroke signifies irreversible infarction. In hyper acute and acute stage of ischaemic stroke focal decreased attenuation was about 10-20 HU. In subacute stage focal parenchymal hypo density further decreased to 20-30 HU. Patients with mild neurological deficit and quick recovery had smaller focal areas of infarct with slight density changes compared to larger territory of infarct extent in patients with severe neurologic symptoms. Conclusions: In subacute stage of ischaemic stroke extent of parenchymal changes and degree of hypo density correlates with stroke severity and may have some prognostic significance. (authors)

  7. Effect of the presence of brain-derived neurotrophic factor val(66)met polymorphism on the recovery in patients with acute subcortical stroke.

    Science.gov (United States)

    Kim, Won-Seok; Lim, Jong Youb; Shin, Joon Ho; Park, Hye Kyung; Tan, Samuel Arnado; Park, Kyoung Un; Paik, Nam-Jong

    2013-06-01

    To investigate the effect of brain-derived neurotrophic factor (BDNF) Val(66)Met polymorphism on the recovery after subcortical stroke, using the modified Rankin Scale (mRS). Subcortical stroke patients with copies of BDNF Val(66)Met polymorphism (n=7) were compared to their controls (n=7) without a copy of BDNF Val(66)Met polymorphism after matching for initial severity, location and type of stroke. The mRS scores at 1 and 3 months after discharge from the neurorehabilitation unit were compared between the groups. A repeated measures ANOVA for mRS revealed significant interaction between time and group (F(2, 24) =37.2, pfactor for recovery and responses to rehabilitation therapies after stroke in Korean patients. There is a need for developing different rehabilitation strategies for the population with BDNF Val(66)Met polymorphism. Further studies assessing different outcomes for various functional domains of stroke recovery are needed to clarify the role of BDNF Val(66)Met polymorphism.

  8. Therapy-induced brain reorganization patterns in aphasia.

    Science.gov (United States)

    Abel, Stefanie; Weiller, Cornelius; Huber, Walter; Willmes, Klaus; Specht, Karsten

    2015-04-01

    Both hemispheres are engaged in recovery from word production deficits in aphasia. Lexical therapy has been shown to induce brain reorganization even in patients with chronic aphasia. However, the interplay of factors influencing reorganization patterns still remains unresolved. We were especially interested in the relation between lesion site, therapy-induced recovery, and beneficial reorganization patterns. Thus, we applied intensive lexical therapy, which was evaluated with functional magnetic resonance imaging, to 14 chronic patients with aphasic word retrieval deficits. In a group study, we aimed to illuminate brain reorganization of the naming network in comparison with healthy controls. Moreover, we intended to analyse the data with joint independent component analysis to relate lesion sites to therapy-induced brain reorganization, and to correlate resulting components with therapy gain. As a result, we found peri-lesional and contralateral activations basically overlapping with premorbid naming networks observed in healthy subjects. Reduced activation patterns for patients compared to controls before training comprised damaged left hemisphere language areas, right precentral and superior temporal gyrus, as well as left caudate and anterior cingulate cortex. There were decreasing activations of bilateral visuo-cognitive, articulatory, attention, and language areas due to therapy, with stronger decreases for patients in right middle temporal gyrus/superior temporal sulcus, bilateral precuneus as well as left anterior cingulate cortex and caudate. The joint independent component analysis revealed three components indexing lesion subtypes that were associated with patient-specific recovery patterns. Activation decreases (i) of an extended frontal lesion disconnecting language pathways occurred in left inferior frontal gyrus; (ii) of a small frontal lesion were found in bilateral inferior frontal gyrus; and (iii) of a large temporo-parietal lesion occurred in

  9. Recovery of post stroke proximal arm function, driven by complex neuroplastic bilateral brain activation patterns and predicted by baseline motor dysfunction severity

    Directory of Open Access Journals (Sweden)

    Svetlana ePundik

    2015-07-01

    Full Text Available Objectives: Neuroplastic changes that drive recovery of shoulder/elbow function after stoke have been poorly understood. The purpose of this study was to determine the relationship between neuroplastic brain changes related to shoulder/elbow movement control in response to treatment and recovery of arm motor function in chronic stroke survivors. Methods: Twenty-three chronic stroke survivors were treated with 12 weeks of arm rehabilitation. Outcome measures included functional Magnetic Resonance Imaging (fMRI for the shoulder/elbow components of reach and a skilled motor function test (Arm Motor Abilities Test (AMAT, collected before and after treatment.Results: We observed two patterns of neuroplastic changes that were associated with gains in motor function: decreased or increased task-related brain activation. Those with significantly better motor function at baseline exhibited a decrease in brain activation in response to treatment, evident in the ipsilesional primary motor and contralesional supplementary motor regions; in contrast, those with greater baseline motor impairment, exhibited increased brain activation in response to treatment. There was an linear relationship between greater functional gain (AMAT and increased activation in bilateral primary motor, contralesional primary and secondary sensory regions, and contralesional lateral premotor area, after adjusting for baseline AMAT, age, and time since stroke. Conclusions: Recovery of functional reach involves recruitment of several contralesional and bilateral primary motor regions. In response to intensive therapy, the direction of functional brain change (i.e. increase or decrease in task-related brain recruitment for shoulder/elbow reach components depends on baseline level of motor function and may represent either different phases or different strategies of neuroplasticity that drive functional recovery.

  10. Acupuncture at Waiguan (SJ5) and sham points influences activation of functional brain areas of ischemic stroke patients: a functional magnetic resonance imaging study

    OpenAIRE

    Qi, Ji; Chen, Junqi; Huang, Yong; Lai, Xinsheng; Tang, Chunzhi; Yang, Junjun; Chen, Hua; Qu, Shanshan

    2014-01-01

    Most studies addressing the specificity of meridians and acupuncture points have focused mainly on the different neural effects of acupuncture at different points in healthy individuals. This study examined the effects of acupuncture on brain function in a pathological context. Sixteen patients with ischemic stroke were randomly assigned to true point group (true acupuncture at right Waiguan (SJ5)) and sham point group (sham acupuncture). Results of functional magnetic resonance imaging revea...

  11. Toward a P300 Based Brain-Computer Interface for Aphasia Rehabilitation after Stroke: Presentation of Theoretical Considerations and a Pilot Feasibility Study

    OpenAIRE

    Kleih, Sonja C.; Gottschalt, Lea; Teichlein, Eva; Weilbach, Franz X.

    2016-01-01

    People with post-stroke motor aphasia know what they would like to say but cannot express it through motor pathways due to disruption of cortical circuits. We present a theoretical background for our hypothesized connection between attention and aphasia rehabilitation and suggest why in this context, Brain-Computer Interfaces (BCI) use might be beneficial for patients diagnosed with aphasia. Not only could BCI technology provide a communication tool, it might support neuronal plasticity by ac...

  12. Acupuncture at Waiguan (TE5) influences activation/deactivation of functional brain areas in ischemic stroke patients and healthy people: A functional MRI study☆

    Science.gov (United States)

    Chen, Junqi; Huang, Yong; Lai, Xinsheng; Tang, Chunzhi; Yang, Junjun; Chen, Hua; Zeng, Tongjun; Wu, Junxian; Qu, Shanshan

    2013-01-01

    In the present study, 10 patients with ischemic stroke in the left hemisphere and six healthy controls were subjected to acupuncture at right Waiguan (TE5). In ischemic stroke subjects, functional MRI showed enhanced activation in Broadmann areas 5, 6, 7, 18, 19, 24, 32, the hypothalamic inferior lobe, the mamillary body, and the ventral posterolateral nucleus of the left hemisphere, and Broadmann areas 4, 6, 7, 18, 19 and 32 of the right hemisphere, but attenuated activation of Broadmann area 13, the hypothalamic inferior lobe, the posterior lobe of the tonsil of cerebellum, and the culmen of the anterior lobe of hypophysis, in the left hemisphere and Broadmann area 13 in the right hemisphere. In ischemic stroke subjects, a number of deactivated brain areas were enhanced, including Broadmann areas 6, 11, 20, 22, 37, and 47, the culmen of the anterior lobe of hypophysis, alae lingulae cerebella, and the posterior lobe of the tonsil of cerebellum of the left hemisphere, and Broadmann areas 8, 37, 45 and 47, the culmen of the anterior lobe of hypophysis, pars tuberalis adenohypophyseos, inferior border of lentiform nucleus, lateral globus pallidus, inferior temporal gyrus, and the parahippocampal gyrus of the right hemisphere. These subjects also exhibited attenuation of a number of deactivated brain areas, including Broadmann area 7. These data suggest that acupuncture at Waiguan specifically alters brain function in regions associated with sensation, vision, and motion in ischemic stroke patients. By contrast, in normal individuals, acupuncture at Waiguan generally activates brain areas associated with insomnia and other functions. PMID:25206592

  13. Effects of Gender and Estrogen Receptors on Iron-Induced Brain Edema Formation.

    Science.gov (United States)

    Xie, Qing; Xi, Guohua; Keep, Richard F; Hua, Ya

    2016-01-01

    Our previous studies have shown that female mice have less brain edema and better recovery in neurological deficits after intracerebral hemorrhage (ICH) and that 17β-estradiol treatment in male mice markedly reduces ICH-induced brain edema. In this study, we investigated the role of gender and the estrogen receptors (ERs) in iron-induced brain edema. There were three parts in this study: (1) either male or female mice received an injection of 10 μL FeCl2 (1 mM) into the right caudate; (2) females received an intracaudate injection of FeCl2 or saline with 1 μg of ICI 182,780 (antagonists of ERs) or vehicle; and (3) males were treated with the ER regulator tamoxifen (5 mg/kg subcutaneously) or vehicle 1 h after FeCl2 injection. Mice were euthanized 24 h later for brain edema determination. FeCl2 induced lower brain edema in females than in males. Co-injection of ICI 182,780 with FeCl2 aggravated iron-induced brain edema in female mice. ICI 182,780 itself did not induce brain edema at the dose of 1 μg. Tamoxifen treatment reduced FeCl2-induced brain edema in male mice. In conclusion, iron induced less brain edema in female mice than in males. ER modification can affect iron-induced brain edema.

  14. Bipyridine, an iron chelator, does not lessen intracerebral iron-induced damage or improve outcome after intracerebral hemorrhagic stroke in rats.

    Science.gov (United States)

    Caliaperumal, Jayalakshmi; Wowk, Shannon; Jones, Sarah; Ma, Yonglie; Colbourne, Frederick

    2013-12-01

    Iron chelators, such as the intracellular ferrous chelator 2,2'-bipyridine, are a potential means of ameliorating iron-induced injury after intracerebral hemorrhage (ICH). We evaluated bipyridine against the collagenase and whole-blood ICH models and a simplified model of iron-induced damage involving a striatal injection of FeCl2 in adult rats. First, we assessed whether bipyridine (25 mg/kg beginning 12 h post-ICH and every 12 h for 3 days) would attenuate non-heme iron levels in the brain and lessen behavioral impairments (neurological deficit scale, corner turn test, and horizontal ladder) 7 days after collagenase-induced ICH. Second, we evaluated bipyridine (20 mg/kg beginning 6 h post-ICH and then every 24 h) on edema 3 days after collagenase infusion. Body temperature was continually recorded in a subset of these rats beginning 24 h prior to ICH until euthanasia. Third, bipyridine was administered (as per experiment 2) after whole-blood infusion to examine tissue loss, neuronal degeneration, and behavioral impairments at 7 days post-stroke, as well as body temperature for 3 days post-stroke. Finally, we evaluated whether bipyridine (25 mg/kg given 2 h prior to surgery and then every 12 h for 3 days) lessens tissue loss, neuronal death, and behavioral deficits after striatal FeCl2 injection. Bipyridine caused a significant hypothermic effect (maximum drop to 34.6 °C for 2-5 h after each injection) in both ICH models; however, in all experiments bipyridine-treated rats were indistinguishable from vehicle controls on all other measures (e.g., tissue loss, behavioral impairments, etc.). These results do not support the use of bipyridine against ICH.

  15. Memory deficit associated with increased brain proinflammatory cytokine levels and neurodegeneration in acute ischemic stroke

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    Bruno Silva

    2015-08-01

    Full Text Available The present study aimed to investigate behavioral changes and neuroinflammatory process following left unilateral common carotid artery occlusion (UCCAO, a model of cerebral ischemia. Post-ischemic behavioral changes following 15 min UCCAO were recorded 24 hours after reperfusion. The novel object recognition task was used to assess learning and memory. After behavioral test, brains from sham and ischemic mice were removed and processed to evaluate central nervous system pathology by TTC and H&E techniques as well as inflammatory mediators by ELISA. UCCAO promoted long-term memory impairment after reperfusion. Infarct areas were observed in the cerebrum by TTC stain. Moreover, the histopathological analysis revealed cerebral necrotic cavities surrounded by ischemic neurons and hippocampal neurodegeneration. In parallel with memory dysfunction, brain levels of TNF-a, IL-1b and CXCL1 were increased post ischemia compared with sham-operated group. These findings suggest an involvement of central nervous system inflammatory mediators and brain damage in cognitive impairment following unilateral acute ischemia.

  16. Combining Growth Factor and Bone Marrow Cell Therapy Induces Bleeding and Alters Immune Response After Stroke in Mice.

    Science.gov (United States)

    Strecker, Jan-Kolja; Olk, Joanna; Hoppen, Maike; Gess, Burkhard; Diederich, Kai; Schmidt, Antje; Schäbitz, Wolf-Rüdiger; Schilling, Matthias; Minnerup, Jens

    2016-03-01

    Bone marrow cell (BMC)-based therapies, either the transplantation of exogenous cells or stimulation of endogenous cells by growth factors like the granulocyte colony-stimulating factor (G-CSF), are considered a promising means of treating stroke. In contrast to large preclinical evidence, however, a recent clinical stroke trial on G-CSF was neutral. We, therefore, aimed to investigate possible synergistic effects of co-administration of G-CSF and BMCs after experimental stroke in mice to enhance the efficacy compared with single treatments. We used an animal model for experimental stroke as paradigm to study possible synergistic effects of co-administration of G-CSF and BMCs on the functional outcome and the pathophysiological mechanism. G-CSF treatment alone led to an improved functional outcome, a reduced infarct volume, increased blood vessel stabilization, and decreased overall inflammation. Surprisingly, the combination of G-CSF and BMCs abrogated G-CSFs' beneficial effects and resulted in increased hemorrhagic infarct transformation, altered blood-brain barrier, excessive astrogliosis, and altered immune cell polarization. These increased rates of infarct bleeding were mainly mediated by elevated matrix metalloproteinase-9-mediated blood-brain barrier breakdown in G-CSF- and BMCs-treated animals combined with an increased number of dilated and thus likely more fragile vessels in the subacute phase after cerebral ischemia. Our results provide new insights into both BMC-based therapies and immune cell biology and help to understand potential adverse and unexpected side effects. © 2016 American Heart Association, Inc.

  17. Clinical usefulness of a biomarker-based diagnostic test for acute stroke: the Biomarker Rapid Assessment in Ischemic Injury (BRAIN) study.

    Science.gov (United States)

    Laskowitz, Daniel T; Kasner, Scott E; Saver, Jeffrey; Remmel, Kerri S; Jauch, Edward C

    2009-01-01

    One of the significant limitations in the evaluation and management of patients with suspected acute cerebral ischemia is the absence of a widely available, rapid, and sensitive diagnostic test. The objective of the current study was to assess whether a test using a panel of biomarkers might provide useful diagnostic information in the early evaluation of stroke by differentiating patients with cerebral ischemia from other causes of acute neurological deficit. A total of 1146 patients presenting with neurological symptoms consistent with possible stroke were prospectively enrolled at 17 different sites. Timed blood samples were assayed for matrix metalloproteinase 9, brain natriuretic factor, d-dimer, and protein S100beta. A separate cohort of 343 patients was independently enrolled to validate the multiple biomarker model approach. A diagnostic tool incorporating the values of matrix metalloproteinase 9, brain natriuretic factor, d-dimer, and S-100beta into a composite score was sensitive for acute cerebral ischemia. The multivariate model demonstrated modest discriminative capabilities with an area under the receiver operating characteristic curve of 0.76 for hemorrhagic stroke and 0.69 for all stroke (likelihood test P<0.001). When the threshold for the logistic model was set at the first quartile, this resulted in a sensitivity of 86% for detecting all stroke and a sensitivity of 94% for detecting hemorrhagic stroke. Moreover, results were reproducible in a separate cohort tested on a point-of-care platform. These results suggest that a biomarker panel may add valuable and time-sensitive diagnostic information in the early evaluation of stroke. Such an approach is feasible on a point-of-care platform. The rapid identification of patients with suspected stroke would expand the availability of time-limited treatment strategies. Although the diagnostic accuracy of the current panel is clearly imperfect, this study demonstrates the feasibility of incorporating a

  18. The role of nitrous oxide in stroke

    Directory of Open Access Journals (Sweden)

    Zhu-wei Zhang

    2017-01-01

    Full Text Available Stroke that is caused by poor blood flow into the brain results in cell death, including ischemia stroke due to lack of blood into brain tissue, and hemorrhage due to bleeding. Both of them will give rise to the dysfunction of brain. In general, the signs and symptoms of stroke are the inability of feeling or moving on one side of body, sometimes loss of vision to one side. Above symptoms will appear soon after the stroke has happened. If the symptoms and signs happen in 1 or 2 hours, we often call them as transient ischemic attack. Moreover, hemorrhagic stroke often leads to severe headache. It is known that neuronal death can happen after stroke, and it depends upon the activation of N-methyl-D-aspartate (NMDA excitatory glutamate receptor which is the goal for a lot of neuroprotective agents. Nitrous oxide was discovered by Joseph Priestley in 1772, and then he and his friends, including the poet Coleridge and Robert Sauce, experimented with the gas. They found this gas could make patients loss the sense of pain and still maintain consciousness after inhalation. Shortly the gas was used as an anesthetic, especially in the field of dentists. Now, accroding to theme of Helene N. David and other scientists, both of nitrous oxide at 75 vol% and xenon at 50 vol% could reduce ischemic neuronal death in the cortex by 70% and decrease NMDA-induced Ca2+ influx by 30%. Therefore, more clinical and experimental studies are important to illuminate the mechanisms of how nitrous oxide protects brain tissue and to explore the best protocol of this gas in stroke treatment.

  19. Microbiota Dysbiosis Controls the Neuroinflammatory Response after Stroke.

    Science.gov (United States)

    Singh, Vikramjeet; Roth, Stefan; Llovera, Gemma; Sadler, Rebecca; Garzetti, Debora; Stecher, Bärbel; Dichgans, Martin; Liesz, Arthur

    2016-07-13

    Acute brain ischemia induces a local neuroinflammatory reaction and alters peripheral immune homeostasis at the same time. Recent evidence has suggested a key role of the gut microbiota in autoimmune diseases by modulating immune homeostasis. Therefore, we investigated the mechanistic link among acute brain ischemia, microbiota alterations, and the immune response after brain injury. Using two distinct models of acute middle cerebral artery occlusion, we show by next-generation sequencing that large stroke lesions cause gut microbiota dysbiosis, which in turn affects stroke outcome via immune-mediated mechanisms. Reduced species diversity and bacterial overgrowth of bacteroidetes were identified as hallmarks of poststroke dysbiosis, which was associated with intestinal barrier dysfunction and reduced intestinal motility as determined by in vivo intestinal bolus tracking. Recolonizing germ-free mice with dysbiotic poststroke microbiota exacerbates lesion volume and functional deficits after experimental stroke compared with the recolonization with a normal control microbiota. In addition, recolonization of mice with a dysbiotic microbiome induces a proinflammatory T-cell polarization in the intestinal immune compartment and in the ischemic brain. Using in vivo cell-tracking studies, we demonstrate the migration of intestinal lymphocytes to the ischemic brain. Therapeutic transplantation of fecal microbiota normalizes brain lesion-induced dysbiosis and improves stroke outcome. These results support a novel mechanism in which the gut microbiome is a target of stroke-induced systemic alterations and an effector with substantial impact on stroke outcome. We have identified a bidirectional communication along the brain-gut microbiota-immune axis and show that the gut microbiota is a central regulator of immune homeostasis. Acute brain lesions induced dysbiosis of the microbiome and, in turn, changes in the gut microbiota affected neuroinflammatory and functional outcome

  20. Ceftriaxone- and N-acetylcysteine-induced brain tolerance to ischemia: Influence on glutamate levels in focal cerebral ischemia.

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    Weronika Krzyżanowska

    Full Text Available One of the major players in the pathophysiology of cerebral ischemia is disrupted homeostasis of glutamatergic neurotransmission, resulting in elevated extracellular glutamate (Glu concentrations and excitotoxicity-related cell death. In the brain, Glu concentrations are regulated by Glu transporters, including Glu transporter-1 (GLT-1 and cystine/Glu antiporter (system xc-. Modulation of these transporters by administration of ceftriaxone (CEF, 200 mg/kg, i.p. or N-acetylcysteine (NAC, 150 mg/kg, i.p. for 5 days before focal cerebral ischemia may induce brain tolerance to ischemia by significantly limiting stroke-related damage and normalizing Glu concentrations. In the present study, focal cerebral ischemia was induced by 90-minute middle cerebral artery occlusion (MCAO. We compared the effects of CEF and NAC pretreatment on Glu concentrations in extracellular fluid and cellular-specific expression of GLT-1 and xCT with the effects of two reference preconditioning methods, namely, ischemic preconditioning and chemical preconditioning in rats. Both CEF and NAC significantly reduced Glu levels in the frontal cortex and hippocampus during focal cerebral ischemia, and this decrease was comparable with the Glu level achieved with the reference preconditioning strategies. The results of immunofluorescence staining of GLT-1 and xCT on astrocytes, neurons and microglia accounted for the observed changes in extracellular Glu levels to a certain extent. Briefly, after MCAO, the expression of GLT-1 on astrocytes decreased, but pretreatment with CEF seemed to prevent this downregulation. In addition, every intervention used in this study seemed to reduce xCT expression on astrocytes and neurons. The results of this study indicate that modulation of Glu transporter expression may restore Glu homeostasis. Moreover, our results suggest that CEF and NAC may induce brain tolerance to ischemia by influencing GLT-1 and system xc- expression levels. These

  1. Intravenous HOE-642 reduces brain edema and Na uptake in the rat permanent middle cerebral artery occlusion model of stroke: evidence for participation of the blood-brain barrier Na/H exchanger.

    Science.gov (United States)

    O'Donnell, Martha E; Chen, Yi-Je; Lam, Tina I; Taylor, Kelleen C; Walton, Jeffrey H; Anderson, Steven E

    2013-02-01

    Cerebral edema forms in the early hours of ischemic stroke by processes involving increased transport of Na and Cl from blood into brain across an intact blood-brain barrier (BBB). Our previous studies provided evidence that the BBB Na-K-Cl cotransporter is stimulated by the ischemic factors hypoxia, aglycemia, and arginine vasopressin (AVP), and that inhibition of the cotransporter by intravenous bumetanide greatly reduces edema and infarct in rats subjected to permanent middle cerebral artery occlusion (pMCAO). More recently, we showed that BBB Na/H exchanger activity is also stimulated by hypoxia, aglycemia, and AVP. The present study was conducted to further investigate the possibility that a BBB Na/H exchanger also participates in edema formation during ischemic stroke. Sprague-Dawley rats were subjected to pMCAO and then brain edema and Na content assessed by magnetic resonance imaging diffusion-weighed imaging and magnetic resonance spectroscopy Na spectroscopy, respectively, for up to 210 minutes. We found that intravenous administration of the specific Na/H exchange inhibitor HOE-642 significantly decreased brain Na uptake and reduced cerebral edema, brain swelling, and infarct volume. These findings support the hypothesis that edema formation and brain Na uptake during the early hours of cerebral ischemia involve BBB Na/H exchanger activity as well as Na-K-Cl cotransporter activity.

  2. Inducible gene manipulations in brain serotonergic neurons of transgenic rats.

    Directory of Open Access Journals (Sweden)

    Tillmann Weber

    Full Text Available The serotonergic (5-HT system has been implicated in various physiological processes and neuropsychiatric disorders, but in many aspects its role in normal and pathologic brain function is still unclear. One reason for this might be the lack of appropriate animal models which can address the complexity of physiological and pathophysiological 5-HT functioning. In this respect, rats offer many advantages over mice as they have been the animal of choice for sophisticated neurophysiological and behavioral studies. However, only recently technologies for the targeted and tissue specific modification of rat genes - a prerequisite for a detailed study of the 5-HT system - have been successfully developed. Here, we describe a rat transgenic system for inducible gene manipulations in 5-HT neurons. We generated a Cre driver line consisting of a tamoxifen-inducible CreERT2 recombinase under the control of mouse Tph2 regulatory sequences. Tissue-specific serotonergic Cre recombinase expression was detected in four transgenic TPH2-CreERT2 rat founder lines. For functional analysis of Cre-mediated recombination, we used a rat Cre reporter line (CAG-loxP.EGFP, in which EGFP is expressed after Cre-mediated removal of a loxP-flanked lacZ STOP cassette. We show an in-depth characterisation of this rat Cre reporter line and demonstrate its applicability for monitoring Cre-mediated recombination in all major neuronal subpopulations of the rat brain. Upon tamoxifen induction, double transgenic TPH2-CreERT2/CAG-loxP.EGFP rats show selective and efficient EGFP expression in 5-HT neurons. Without tamoxifen administration, EGFP is only expressed in few 5-HT neurons which confirms minimal background recombination. This 5-HT neuron specific CreERT2 line allows Cre-mediated, inducible gene deletion or gene overexpression in transgenic rats which provides new opportunities to decipher the complex functions of the mammalian serotonergic system.

  3. Exercise-induced muscle fatigue in the unaffected knee joint and its influence on postural control and lower limb kinematics in stroke patients

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    Sun Wook Park

    2017-01-01

    Full Text Available This study aimed to investigate the effects of exercise-induced muscle fatigue in the unaffected knee joint on postural control and kinematic changes in stroke patients. Forty participants (20 stroke patients, 20 age-matched healthy participants were recruited. To induce fatigue, maximum voluntary isometric contractions were performed in the unaffected knee joint in a Leg Extension Rehab exercise machine using the pneumatic resistance. We measured static and dynamic balance and lower-limb kinematics during gait. Changes in postural control parameters anteroposterior sway speed and total center of pressure distance differed significantly between the stroke and control groups. In addition, changes in gait kinematic parameters knee and ankle angles of initial contact differed significantly between stroke (paretic and non-paretic and control groups. Muscle fatigue in the unaffected knee and ankle impaired postural control and debilitates kinematic movement of ipsilateral and contralateral lower limbs, and may place the fatigued stroke patients at greater risk for falls.

  4. Volumetric Integral Phase-shift Spectroscopy for Noninvasive Detection of Hemispheric Bioimpedance Asymmetry in Acute Brain Pathology

    Science.gov (United States)

    2018-01-18

    Stroke; Stroke, Acute; Ischemic Stroke; Hemorrhage; Clot (Blood); Brain; Subarachnoid Hemorrhage; Cerebral Infarction; Cerebral Hemorrhage; Cerebral Stroke; Intracerebral Hemorrhage; Intracerebral Injury

  5. Rodent stroke induced by photochemical occlusion of proximal middle cerebral artery: Evolution monitored with MR imaging and histopathology

    Energy Technology Data Exchange (ETDEWEB)

    Chen Feng [Department of Radiology, Faculty of Medicine, Catholic University of Leuven (Belgium); Department of Radiology, Zhong Da Hospital, Southeast University, Nanjing (China); Suzuki, Yasuhiro [Department of Molecular and Vascular Biology, Faculty of Medicine, Catholic University of Leuven (Belgium); Department of Pharmacology, Hamamashu University, Hamamashu (Japan); Nagai, Nobuo [Department of Molecular and Vascular Biology, Faculty of Medicine, Catholic University of Leuven (Belgium); Jin, Lixin [Department of Radiology, Faculty of Medicine, Catholic University of Leuven (Belgium); Yu Jie [Department of Radiology, Faculty of Medicine, Catholic University of Leuven (Belgium); Wang Huaijun [Department of Radiology, Faculty of Medicine, Catholic University of Leuven (Belgium); Marchal, Guy [Department of Radiology, Faculty of Medicine, Catholic University of Leuven (Belgium); Ni Yicheng [Department of Radiology, Faculty of Medicine, Catholic University of Leuven (Belgium)]. E-mail: Yicheng.Ni@med.kuleuven.ac.be

    2007-07-15

    Purpose: To longitudinally investigate stroke in rats after photothrombotic occlusion of proximal middle cerebral artery (MCA) with magnetic resonance imaging (MRI) in correlation with histopathology. Materials and methods: Forty-two rats were subjected to photochemical MCA occlusion and MRI at 1.5 T, and sacrificed in seven groups (n = 6 each) at the following time points: 1, 3, 6 and 12 h, and at day 1, 3 and 9. T2-weighted (T2WI) and diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) map was performed in all rats. Contrast-enhanced T1-weighted imaging (CE-T1WI) was compared to intravital staining with Evans blue in one group for assessing blood-brain barrier (BBB) integrity. The brain was stained histochemically with triphenyl tetrazolium chloride (TTC) and processed for pathological assessment. The evolutional changes of relative lesion volume, signal intensity (SI), and the BBB integrity on MRI with corresponding histopathology were evaluated. Results: The ischemic lesion volume reached a maximum around 12 h to day 1 as visualized successively by DWI, ADC map and T2WI, implicating the evolving pathology from cytotoxic edema through vasogenic edema to tissue death. The ADC of brain infarction underwent a significant reversion after 12 h, reflecting the colliquative necrosis. On CE-T1WI, BBB leakage peaked at 6 h and at day 3 with a transitional partial recovery around 24 h. The infarct volume on T2WI, DWI and ADC map matched well with that on TTC staining at 12 h and at day 1 (p > 0.05). Conclusion: The evolution of the present photothrombotic stroke model in rats could be characterized by MRI. The obtained information may help longitudinal studies of cerebral ischemia and anti-stroke agents using the same model.

  6. Protective Effects of L-902,688, a Prostanoid EP4 Receptor Agonist, against Acute Blood-Brain Barrier Damage in Experimental Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Kelly M. DeMars

    2018-02-01

    Full Text Available Ischemic stroke occurs when a clot forms in the brain vasculature that starves downstream tissue of oxygen and nutrients resulting in cell death. The tissue immediately downstream of the blockage, the core, dies within minutes, but the surrounding tissue, the penumbra is potentially salvageable. Prostaglandin E2 binds to four different G-protein coupled membrane receptors EP1–EP4 mediating different and sometimes opposing responses. Pharmacological activation of the EP4 receptor has already been established as neuroprotective in stroke, but the mechanism(s of protection are not well-characterized. In this study, we hypothesized that EP4 receptor activation reduces ischemic brain injury by reducing matrix metalloproteinase (MMP-3/-9 production and blood-brain barrier (BBB damage. Rats underwent transient ischemic stroke for 90 min. Animals received an intravenous injection of either the vehicle or L-902,688, a highly specific EP4 agonist, at the onset of reperfusion. Brain tissue was harvested at 24 h. We established a dose-response curve and used the optimal dose that resulted in the greatest infarct reduction to analyze BBB integrity compared to vehicle-treated rats. The presence of IgG, a blood protein, in the brain parenchyma is a marker of BBB damage, and L-902,688 (1 mg/kg; i.v. dramatically reduced IgG extravasation (P < 0.05. Consistent with these data, we assessed zona occludens-1 and occludin, tight junction proteins integral to the maintenance of the BBB, and found reduced degradation with L-902,688 administration. With immunoblotting, qRT-PCR, and/or a fluorescence resonance energy transfer (FRET-based activity assay, we next measured MMP-3/-9 since they are key effectors of BBB breakdown in stroke. In the cerebral cortex, not only was MMP-3 activity significantly decreased (P < 0.05, but L-902,688 treatment also reduced MMP-9 mRNA, protein, and enzymatic activity (P < 0.001. In addition, post-ischemic administration of the EP4

  7. Mechanisms of Brain Glucocorticoid Resistance in Stress-Induced Psychopathologies.

    Science.gov (United States)

    Merkulov, V M; Merkulova, T I; Bondar, N P

    2017-03-01

    Exposure to stress activates the hypothalamic-pituitary-adrenal axis and leads to increased levels of glucocorticoid (GC) hormones. Prolonged elevation of GC levels causes neuronal dysfunction, decreases the density of synapses, and impairs neuronal plasticity. Decreased sensitivity to glucocorticoids (glucocorticoid resistance) that develops as a result of chronic stress is one of the characteristic features of stress-induced psychopathologies. In this article, we reviewed the published data on proposed molecular mechanisms that contribute to the development of glucocorticoid resistance in brain, including changes in the expression of the glucocorticoid receptor (GR) gene, biosynthesis of GR isoforms, and GR posttranslational modifications. We also present data on alterations in the expression of the FKBP5 gene encoding the main component of cell ultra-short negative feedback loop of GC signaling regulation. Recent discoveries on stress- and GR-induced changes in epigenetic modification patterns as well as normalizing action of antidepressants are discussed. GR and FKBP5 gene polymorphisms associated with stress-induced psychopathologies are described, and their role in glucocorticoid resistance is discussed.

  8. Hydrogels-Assisted Cell Engraftment for Repairing the Stroke-Damaged Brain: Chimera or Reality

    Directory of Open Access Journals (Sweden)

    Daniel González-Nieto

    2018-02-01

    Full Text Available The use of advanced biomaterials as a structural and functional support for stem cells-based therapeutic implants has boosted the development of tissue engineering applications in multiple clinical fields. In relation to neurological disorders, we are still far from the clinical reality of restoring normal brain function in neurodegenerative diseases and cerebrovascular disorders. Hydrogel polymers show unique mechanical stiffness properties in the range of living soft tissues such as nervous tissue. Furthermore, the use of these polymers drastically enhances the engraftment of stem cells as well as their capacity to produce and deliver neuroprotective and neuroregenerative factors in the host tissue. Along this article, we review past and current trends in experimental and translational research to understand the opportunities, benefits, and types of tentative hydrogel-based applications for the treatment of cerebral disorders. Although the use of hydrogels for brain disorders has been restricted to the experimental area, the current level of knowledge anticipates an intense development of this field to reach clinics in forthcoming years.

  9. Complexity in differentiating the expression of truncated or matured forms of MMP-2 and MMP-9 through zymography in rat brain tissues after acute ischaemic stroke.

    Science.gov (United States)

    Alam, Mustafa; Shuaib, Ashfaq

    2013-05-30

    Matrix metalloproteinases (MMPs) play an important role in the pathogenesis of ischaemic stroke. In particular, the mature forms of MMPs 2 and 9 have similar sizes and share gelatine as a common substrate. Both MMPs are upregulated in ischaemic stroke and play detrimental roles during stroke pathogenesis. Throughout this study, we demonstrated that pro-MMP-2 and pro-MMP-9 from ischaemic rat brain tissue homogenate is detected either through immunoblotting or zymography because of the remarkable size difference between these enzymes (72 versus 95 kDa, respectively). However, the mature MMP-2 and MMP-9 cannot be discriminated through zymography because of the almost identical sizes of these forms (66 and 67 kDa, respectively). The use of gelatine zymography on ischaemic rat brain tissue homogenate revealed a 65-kDa MMP band, corresponding to the heterogeneous band of mature MMP-2 and/or MMP-9. Furthermore, we also detected mature MMPs of 65 kDa generated from both recombinant human MMP-2 and MMP-9. Using a pull down assay in rat brain tissue homogenate with gelatine-agarose beads, we showed increased activities for both the pro and mature forms of MMP-2 and MMP-9. However, we could not determine the origin of the respective mature MMPs from the heterogeneous band. Thus, in this study, we demonstrated that the identification and quantification of mature MMP-2 and MMP-9 could not be achieved using zymography alone. Therefore, the development of a reliable technique to identify and measure the respective MMPs is needed to test new stroke therapies targeting MMP-2 and MMP-9. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Recovery in stroke rehabilitation through the rotation of preferred directions induced by bimanual movements: a computational study.

    Directory of Open Access Journals (Sweden)

    Ken Takiyama

    Full Text Available Stroke patients recover more effectively when they are rehabilitated with bimanual movement rather than with unimanual movement; however, it remains unclear why bimanual movement is more effective for stroke recovery. Using a computational model of stroke recovery, this study suggests that bimanual movement facilitates the reorganization of a damaged motor cortex because this movement induces rotations in the preferred directions (PDs of motor cortex neurons. Although the tuning curves of these neurons differ during unimanual and bimanual movement, changes in PD, but not changes in modulation depth, facilitate such reorganization. In addition, this reorganization was facilitated only when encoding PDs are rotated, but decoding PDs are not rotated. Bimanual movement facilitates reorganization because this movement changes neural activities through inter-hemispheric inhibition without changing cortical-spinal-muscle connections. Furthermore, stronger inter-hemispheric inhibition between motor cortices results in more effective reorganization. Thus, this study suggests that bimanual movement is effective for stroke rehabilitation because this movement rotates the encoding PDs of motor cortex neurons.

  11. Sit-to-Stand in People with Stroke: Effect of Lower Limb Constraint-Induced Movement Strategies

    Directory of Open Access Journals (Sweden)

    Charla Krystine Gray

    2014-01-01

    Full Text Available Background. Weight-bearing asymmetry and impaired balance may contribute to the increased fall risk in people with stroke when rising to stand from sitting. Objective. This study investigated the effect of constraint-induced movement (CIM strategies on weight-bearing symmetry and balance during sit-to-stand in people with stroke. Methods. A nonrandom convenience sample of fifteen people with stroke performed the sit-to-stand task using three CIM strategies including a solid or compliant (foam block strategy, with the unaffected limb placed on the block, and an asymmetrical foot position strategy, with the unaffected limb placed ahead of the affected limb. Duration of the task, affected limb weight-bearing, and centre of pressure and centre of mass displacement were measured in the frontal and sagittal plane. Results. Affected limb weight-bearing was increased and frontal plane centre of pressure and centre of mass moved toward the affected limb compared to baseline with all CIM strategies. Centre of mass displacement in the sagittal plane was greater with the compliant block and asymmetrical foot strategies. Conclusions. The CIM strategies demonstrated greater loading of the affected limb and movement of the centre of pressure and centre of mass toward the affected limb. The compliant block and asymmetrical foot conditions may challenge sagittal plane balance during sit-to-stand in people with stroke.

  12. Excess Stroke in Mexican Americans Compared with Non-Hispanic Whites: The Brain Attack Surveillance in Corpus Christi Project

    OpenAIRE

    Morgenstern, Lewis B.; Smith, Melinda A.; Lisabeth, Lynda D.; Risser, Jan M. H.; Uchino, Ken; Garcia, Nelda; Longwell, Paxton J.; McFarling, David A.; Akuwumi, Olubumi; Al-Wabil, Areej; Al-Senani, Fahmi; Brown, Devin L.; Moyé, Lemuel A.

    2004-01-01

    Mexican Americans are the largest subgroup of Hispanics, the largest minority population in the United States. Stroke is the leading cause of disability and third leading cause of death. The authors compared stroke incidence among Mexican Americans and non-Hispanic Whites in a population-based study. Stroke cases were ascertained in Nueces County, Texas, utilizing concomitant active and passive surveillance. Cases were validated on the basis of source documentation by board-certified neurolog...

  13. Primary blast-induced traumatic brain injury: lessons from lithotripsy

    Science.gov (United States)

    Nakagawa, A.; Ohtani, K.; Armonda, R.; Tomita, H.; Sakuma, A.; Mugikura, S.; Takayama, K.; Kushimoto, S.; Tominaga, T.

    2017-11-01

    Traumatic injury caused by explosive or blast events is traditionally divided into four mechanisms: primary, secondary, tertiary, and quaternary blast injury. The mechanisms of blast-induced traumatic brain injury (bTBI) are biomechanically distinct and can be modeled in both in vivo and in vitro systems. The primary bTBI injury mechanism is associated with the response of brain tissue to the initial blast wave. Among the four mechanisms of bTBI, there is a remarkable lack of information regarding the mechanism of primary bTBI. On the other hand, 30 years of research on the medical application of shock waves (SWs) has given us insight into the mechanisms of tissue and cellular damage in bTBI, including both air-mediated and underwater SW sources. From a basic physics perspective, the typical blast wave consists of a lead SW followed by shock-accelerated flow. The resultant tissue injury includes several features observed in primary bTBI, such as hemorrhage, edema, pseudo-aneurysm formation, vasoconstriction, and induction of apoptosis. These are well-described pathological findings within the SW literature. Acoustic impedance mismatch, penetration of tissue by shock/bubble interaction, geometry of the skull, shear stress, tensile stress, and subsequent cavitation formation are all important factors in determining the extent of SW-induced tissue and cellular injury. In addition, neuropsychiatric aspects of blast events need to be taken into account, as evidenced by reports of comorbidity and of some similar symptoms between physical injury resulting in bTBI and the psychiatric sequelae of post-traumatic stress. Research into blast injury biophysics is important to elucidate specific pathophysiologic mechanisms of blast injury, which enable accurate differential diagnosis, as well as development of effective treatments. Herein we describe the requirements for an adequate experimental setup when investigating blast-induced tissue and cellular injury; review SW physics

  14. Feasibility of task-specific brain-machine interface training for upper-extremity paralysis in patients with chronic hemiparetic stroke.

    Science.gov (United States)

    Nishimoto, Atsuko; Kawakami, Michiyuki; Fujiwara, Toshiyuki; Hiramoto, Miho; Honaga, Kaoru; Abe, Kaoru; Mizuno, Katsuhiro; Ushiba, Junichi; Liu, Meigen

    2018-01-10

    Brain-machine interface training was developed for upper-extremity rehabilitation for patients with severe hemiparesis. Its clinical application, however, has been limited because of its lack of feasibility in real-world rehabilitation settings. We developed a new compact task-specific brain-machine interface system that enables task-specific training, including reach-and-grasp tasks, and studied its clinical feasibility and effectiveness for upper-extremity motor paralysis in patients with stroke. Prospective beforeâ€"after study. Twenty-six patients with severe chronic hemiparetic stroke. Participants were trained with the brain-machine interface system to pick up and release pegs during 40-min sessions and 40 min of standard occupational therapy per day for 10 days. Fugl-Meyer upper-extremity motor (FMA) and Motor Activity Log-14 amount of use (MAL-AOU) scores were assessed before and after the intervention. To test its feasibility, 4 occupational therapists who operated the system for the first time assessed it with the Quebec User Evaluation of Satisfaction with assistive Technology (QUEST) 2.0. FMA and MAL-AOU scores improved significantly after brain-machine interface training, with the effect sizes being medium and large, respectively (pbrain-machine interface system is feasible for use in real-world clinical settings.

  15. Brain computed tomography using iterative reconstruction to diagnose acute middle cerebral artery stroke: usefulness in combination of narrow window setting and thin slice reconstruction.

    Science.gov (United States)

    Inoue, Taihei; Nakaura, Takeshi; Yoshida, Morikatsu; Yokoyama, Koichi; Uetani, Hiroyuki; Oda, Seitaro; Utsunomiya, Daisuke; Kitajima, Mika; Harada, Kazunori; Yamashita, Yasuyuki

    2018-04-01

    The purpose of this study is to determine whether iterative model reconstruction (IMR) optimized for brain CT could improve the detection of acute stroke in the setting of thin image slices and narrow window settings. We retrospectively reviewed 27 patients who presented acute middle cerebral artery (MCA) stroke. Images were reconstructed using filtered back projection (FBP; 1- and 5-mm slice thickness) and IMR (1 mm thickness), and contrast-to-noise ratios (CNRs) of infarcted and non-infarcted areas were compared. To analyze the performance of acute MCA stroke detection, we used receiver operating characteristic (ROC) curve techniques and compared 5-mm FBP with standard and narrow window settings, and 1-mm FBP and IMR with narrow window settings. The CNR in 1-mm IMR (1.1 ± 1.0) was significantly higher than in 5- (0.8 ± 0.7) and 1-mm FBP (0.4 ± 0.4) (p window settings (0.90, 95% CI: 0.86, 0.94) than it was with 5-mm FBP (0.78, 95% CI: 0.72, 0.83). The combination of thin image slices and narrow window settings under IMR reconstruction provide better diagnostic performance for acute MCA stroke than conventional reconstruction methods.

  16. An exploratory intervention study suggests clinical benefits of training in chronic stroke to be paralleled by changes in brain activity using repeated fMRI.

    Science.gov (United States)

    Landsmann, Barbara; Pinter, Daniela; Pirker, Eva; Pichler, Gerald; Schippinger, Walter; Weiss, Elisabeth M; Mathie, Gabriel; Gattringer, Thomas; Fazekas, Franz; Enzinger, Christian

    2016-01-01

    Previous studies demonstrated changes in sensorimotor network activation over time after stroke that have been interpreted as partly compensatory. Locomotor and balance trainings may improve both mobility and cognition even in chronic stroke and thereby impact on cerebral activation patterns. We here aimed at testing these assumptions in an exploratory study to inform subsequent larger intervention studies. Eight patients (73.3±4.4 years) with a chronic lacunar stroke (mean interval 3.7 years after the acute event with a range from 2 to 4 years) and residual leg paresis leading to gait disturbance received a guided 5-week training focusing on mobility, endurance, and coordination. Before and afterward, they underwent clinical, neuropsychological, and gait assessments and brain MRI at 3 T including a functional ankle movement paradigm. Sixteen healthy controls (HCs; 68.8±5.4 years) followed the same protocol without intervention. After training, patients had improved in mobility, memory, and delayed recall of memory. While cerebral activations in HC remained completely unaltered, patients showed increased activations in the right precentral gyrus, the right and left superior frontal gyri, and the right frontal lobe, with bipedal ankle movements after training. In this exploratory study of chronic stroke, we found not only significant effects of physical training on mobility but also distinct aspects of cognition already with a small number of highly selected patients. These improvements were paralleled by alterations in cerebral activity possibly reflecting neuronal plasticity. Larger studies including randomization are needed.

  17. Stroke Treatments

    Science.gov (United States)

    ... Month Infographic Stroke Hero F.A.S.T. Quiz Stroke Treatment Stroke used to rank fourth in leading causes of ... type of treatment depends on the type of stroke. Ischemic stroke happens when a clot blocks a ...

  18. Brain Aneurysm

    Science.gov (United States)

    ... thin tissues covering the brain. This type of hemorrhagic stroke is called a subarachnoid hemorrhage. A ruptured aneurysm quickly becomes life-threatening and requires prompt medical treatment. Most brain aneurysms, however, don't rupture, create ...

  19. Mapping cortical hand motor representation using TMS: A method to assess brain plasticity and a surrogate marker for recovery of function after stroke?

    Science.gov (United States)

    Lüdemann-Podubecká, Jitka; Nowak, Dennis Alexander

    2016-10-01

    Stroke is associated with reorganization within motor areas of both hemispheres. Mapping the cortical hand motor representation using transcranial magnetic stimulation may help to understand the relationship between motor cortex reorganization and motor recovery of the affected hand after stroke. A standardized review of the pertinent literature was performed. We identified 20 trials, which analyzed the relationship between the extent and/or location of cortical hand motor representation using transcranial magnetic stimulation and motor function and recovery of the affected hand. Several correlations were found between cortical reorganization and measures of hand motor impairment and recovery. A better understanding of the relationships between the extent and location of cortical hand motor representation and the motor impairment and motor recovery of the affected hand after stroke may contribute to a targeted use of non-invasive brain stimulation protocols. In the future motor mapping may help to guide brain stimulation techniques to the most effective motor area in an affected individual. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. 3D movement correction of CT brain perfusion image data of patients with acute ischemic stroke

    International Nuclear Information System (INIS)

    Fahmi, Fahmi; Marquering, Henk A.; Streekstra, Geert J.; Borst, Jordi; Beenen, Ludo F.M.; Majoie, Charles B.L.; Niesten, Joris M.; Velthuis, Birgitta K.; VanBavel, Ed

    2014-01-01

    Head movement during CT brain perfusion (CTP) acquisition can deteriorate the accuracy of CTP analysis. Most CTP software packages can only correct in-plane movement and are limited to small ranges. The purpose of this study is to validate a novel 3D correction method for head movement during CTP acquisition. Thirty-five CTP datasets that were classified as defective due to head movement were included in this study. All CTP time frames were registered with non-contrast CT data using a 3D rigid registration method. Location and appearance of ischemic area in summary maps derived from original and registered CTP datasets were qualitative compared with follow-up non-contrast CT. A quality score (QS) of 0 to 3 was used to express the degree of agreement. Furthermore, experts compared the quality of both summary maps and assigned the improvement score (IS) of the CTP analysis, ranging from -2 (much worse) to 2 (much better). Summary maps generated from corrected CTP significantly agreed better with appearance of infarct on follow-up CT with mean QS 2.3 versus mean QS 1.8 for summary maps from original CTP (P = 0.024). In comparison to original CTP data, correction resulted in a quality improvement with average IS 0.8: 17 % worsened (IS = -2, -1), 20 % remained unchanged (IS = 0), and 63 % improved (IS = +1, +2). The proposed 3D movement correction improves the summary map quality for CTP datasets with severe head movement. (orig.)

  1. 3D movement correction of CT brain perfusion image data of patients with acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Fahmi, Fahmi [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); University of Sumatera Utara, Department of Electrical Engineering, Medan (Indonesia); Marquering, Henk A.; Streekstra, Geert J. [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Borst, Jordi; Beenen, Ludo F.M.; Majoie, Charles B.L. [Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Niesten, Joris M.; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); VanBavel, Ed [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Collaboration: on behalf of the DUST study

    2014-06-15

    Head movement during CT brain perfusion (CTP) acquisition can deteriorate the accuracy of CTP analysis. Most CTP software packages can only correct in-plane movement and are limited to small ranges. The purpose of this study is to validate a novel 3D correction method for head movement during CTP acquisition. Thirty-five CTP datasets that were classified as defective due to head movement were included in this study. All CTP time frames were registered with non-contrast CT data using a 3D rigid registration method. Location and appearance of ischemic area in summary maps derived from original and registered CTP datasets were qualitative compared with follow-up non-contrast CT. A quality score (QS) of 0 to 3 was used to express the degree of agreement. Furthermore, experts compared the quality of both summary maps and assigned the improvement score (IS) of the CTP analysis, ranging from -2 (much worse) to 2 (much better). Summary maps generated from corrected CTP significantly agreed better with appearance of infarct on follow-up CT with mean QS 2.3 versus mean QS 1.8 for summary maps from original CTP (P = 0.024). In comparison to original CTP data, correction resulted in a quality improvement with average IS 0.8: 17 % worsened (IS = -2, -1), 20 % remained unchanged (IS = 0), and 63 % improved (IS = +1, +2). The proposed 3D movement correction improves the summary map quality for CTP datasets with severe head movement. (orig.)

  2. Lifetime stress cumulatively programs brain transcriptome and impedes stroke recovery: benefit of sensory stimulation.

    Directory of Open Access Journals (Sweden)

    Fabíola C R Zucchi

    Full Text Available Prenatal stress (PS represents a critical variable affecting lifetime health trajectories, metabolic and vascular functions. Beneficial experiences may attenuate the effects of PS and its programming of health outcomes in later life. Here we investigated in a rat model (1 if PS modulates recovery following cortical ischemia in adulthood; (2 if a second hit by adult stress (AS exaggerates stress responses and ischemic damage; and (3 if tactile stimulation (TS attenuates the cumulative effects of PS and AS. Prenatally stressed and non-stressed adult male rats underwent focal ischemic motor cortex lesion and were tested in skilled reaching and skilled walking tasks. Two groups of rats experienced recurrent restraint stress in adulthood and one of these groups also underwent daily TS therapy. Animals that experienced both PS and AS displayed the most severe motor disabilities after lesion. By contrast, TS promoted recovery from ischemic lesion and reduced hypothalamic-pituitary-adrenal axis activity. The data also showed that cumulative effects of adverse and beneficial lifespan experiences interact with disease outcomes and brain plasticity through the modulation of gene expression. Microarray analysis of the lesion motor cortex revealed that cumulative PS and AS interact with genes related to growth factors and transcription factors, which were not affected by PS or lesion alone. TS in PS+AS animals reverted these changes, suggesting a critical role for these factors in activity-dependent motor cortical reorganization after ischemic lesion. These findings suggest that beneficial experience later in life can moderate adverse consequences of early programming to improve cerebrovascular health.

  3. Lifetime Stress Cumulatively Programs Brain Transcriptome and Impedes Stroke Recovery: Benefit of Sensory Stimulation

    Science.gov (United States)

    Zucchi, Fabíola C. R.; Yao, Youli; Ilnytskyy, Yaroslav; Robbins, Jerrah C.; Soltanpour, Nasrin; Kovalchuk, Igor; Kovalchuk, Olga; Metz, Gerlinde A. S.

    2014-01-01

    Prenatal stress (PS) represents a critical variable affecting lifetime health trajectories, metabolic and vascular functions. Beneficial experiences may attenuate the effects of PS and its programming of health outcomes in later life. Here we investigated in a rat model (1) if PS modulates recovery following cortical ischemia in adulthood; (2) if a second hit by adult stress (AS) exaggerates stress responses and ischemic damage; and (3) if tactile stimulation (TS) attenuates the cumulative effects of PS and AS. Prenatally stressed and non-stressed adult male rats underwent focal ischemic motor cortex lesion and were tested in skilled reaching and skilled walking tasks. Two groups of rats experienced recurrent restraint stress in adulthood and one of these groups also underwent daily TS therapy. Animals that experienced both PS and AS displayed the most severe motor disabilities after lesion. By contrast, TS promoted recovery from ischemic lesion and reduced hypothalamic-pituitary-adrenal axis activity. The data also showed that cumulative effects of adverse and beneficial lifespan experiences interact with disease outcomes and brain plasticity through the modulation of gene expression. Microarray analysis of the lesion motor cortex revealed that cumulative PS and AS interact with genes related to growth factors and transcription factors, which were not affected by PS or lesion alone. TS in PS+AS animals reverted these changes, suggesting a critical role for these factors in activity-dependent motor cortical reorganization after ischemic lesion. These findings suggest that beneficial experience later in life can moderate adverse consequences of early programming to improve cerebrovascular health. PMID:24651125

  4. Moving Beyond the Brain: Transcutaneous Spinal Direct Current Stimulation in Post-Stroke Aphasia

    Directory of Open Access Journals (Sweden)

    Paola Marangolo

    2017-08-01

    Full Text Available Over the last 20 years, major advances in cognitive neuroscience have clearly shown that the language function is not restricted into the classical language areas but it involves brain regions, which had never previously considered. Indeed, recent lines of evidence have suggested that the processing of words associated to motor schemata, such as action verbs, modulates the activity of the sensorimotor cortex, which, in turn, facilitates its retrieval. To date, no studies have investigated whether the spinal cord, which is functionally connected to the sensorimotor system, might also work as an auxiliary support for language processing. We explored the combined effect of transcutaneous spinal direct current stimulation (tsDCS and language treatment in a randomized double-blind design for the recovery of verbs and nouns in 14 chronic aphasics. During each treatment, each subject received tsDCS (20 min, 2 mA over the thoracic vertebrae (10th vertebra in three different conditions: (1 anodic, (2 cathodic and (3 sham, while performing a verb and noun naming tasks. Each experimental condition was run in five consecutive daily sessions over 3 weeks. Overall, a significant greater improvement in verb naming was found during the anodic condition with respect to the other two conditions, which persisted at 1 week after the end of the treatment. No significant differences were present for noun naming among the three conditions. The hypothesis is advanced that anodic tsDCS might have influenced activity along the ascending somatosensory pathways, ultimately eliciting neurophysiological changes into the sensorimotor areas which, in turn, supported the retrieval of verbs. These results further support the evidence that action words, due to their sensorimotor semantic properties, are partly represented into the sensorimotor cortex. Moreover, they also document, for the first time, that tsDCS enhances verb recovery in chronic aphasia and it may

  5. Stroke - risk factors

    Science.gov (United States)

    ... Brain cells can die, causing lasting damage. Risk factors are things that increase your chance of getting ... disease or condition. This article discusses the risk factors for stroke and things you can do to ...

  6. Comparison of ADC map with trace map in the normal and infarct areas of the brains of stroke patients

    International Nuclear Information System (INIS)

    Kim, Seung Hyung; Yoon, Pyeong Ho; Jeong, Eun Kee; Oh, Young Taick; Kim, Dong Ik

    1999-01-01

    To compare ADC mapping with trace mapping in normal and infarct areas of the brains of stroke patients. Eighteen patients diagnosed on the basis of clinical and brain MRI examinations as suffering from brain infarction were included in this study (hyperacute-1, acute-4, subacute-12, chronic-1). Diffusion weighted images of three orthogonal directions of a patient's brain were obtained by means of a single shot EPI pulse sequence, using a diffusion gradient with four serial b-factors. Three ADC maps were then reconstructed by post-image processing and were summed pixel by pixel to yield a trace map. ROIs were selected in the normal areas of white matter, gray matter and CSF of one hemisphere, and other ROIs of the same size were selected at the same site of the contralateral hemisphere. ADC and trace values were measured and right/left ratios of ADC and trace values were calculated. Using these values, we then compared the ADC map with the trace map, and compared the degree of anisotropic diffusion between white matter, gray matter and CSF. Except for three, whose infarct lesions were small and lay over white and gray matter, patients were divided into two groups. Those with infarct in the white matter (n=10) were assigned to one group, and those with infarct in the gray matter (n=5) to the other. ROIs were selected in the infarct area and other ROIs of the same size were selected at the same site of the contralateral hemisphere. ADC and trace values were measured and infarct/contralateral ratios were calculated. We then compared ADC ratio with trace ratio in white matter and gray matter infarct. In normal white matter, the Dxx ratio was 0.980±0.098, the Dyy ratio 1.019±0.086, the Dzz ratio 0.999±0.111, and the trace ratio 0.995±0.031. In normal gray matter, the Dxx ratio was 1.001±0.058, the Dyy ratio 0.996±0.063, Dzz ratio 1.005±0.070, and the trace ratio 1.001±0.028. In CSF, the Dxx ratio was 1.002±0.064, the Dyy ratio 1.023±0.055, the Dzz ratio 0.999

  7. Reactive Balance in Individuals With Chronic Stroke: Biomechanical Factors Related to Perturbation-Induced Backward Falling.

    Science.gov (United States)

    Salot, Pooja; Patel, Prakruti; Bhatt, Tanvi

    2016-03-01

    An effective compensatory stepping response is the first line of defense for preventing a fall during sudden large external perturbations. The biomechanical factors that contribute to heightened fall risk in survivors of stroke, however, are not clearly understood. It is known that impending sensorimotor and balance deficits poststroke predispose these individuals to a risk of fall during sudden external perturbations. The purpose of this study was to examine the mechanism of fall risk in survivors of chronic stroke when exposed to sudden, slip-like forward perturbations in stance. This was a cross-sectional study. Fourteen individuals with stroke, 14 age-matched controls (AC group), and 14 young controls (YC group) were exposed to large-magnitude forward stance perturbations. Postural stability was computed as center of mass (COM) position (XCOM/BOS) and velocity (ẊCOM/BOS) relative to the base of support (BOS) at first step lift-off (LO) and touch-down (TD) and at second step TD. Limb support was quantified as vertical hip descent (Zhip) from baseline after perturbation onset. All participants showed a backward balance loss, with 71% of the stroke group experiencing a fall compared with no falls in the control groups (AC and YC groups). At first step LO, no between-group differences in XCOM/BOS and ẊCOM/BOS were noted. At first step TD, however, the stroke group had a significantly posterior XCOM/BOS and backward ẊCOM/BOS compared with the control groups. At second step TD, individuals with stroke were still more unstable (more posterior XCOM/BOS and backward ẊCOM/BOS) compared with the AC group. Individuals with stroke also showed greater peak Zhip compared with the control groups. Furthermore, the stroke group took a larger number of steps with shorter step length and delayed step initiation compared with the control groups. Although the study highlights the reactive balance deficits increasing fall risk in survivors of stroke compared with healthy

  8. Increased Brain-Specific MiR-9 and MiR-124 in the Serum Exosomes of Acute Ischemic Stroke Patients.

    Directory of Open Access Journals (Sweden)

    Qiuhong Ji

    Full Text Available The aims of this study were to examine the alternation in serum exosome concentrations and the levels of serum exosomal miR-9 and miR-124, two brain-specific miRNAs, in acute ischemic stroke (AIS patients and to explore the predictive values of these miRNAs for AIS diagnosis and damage evaluation. Sixty-five patients with AIS at the acute stage were enrolled and 66 non-stroke volunteers served as controls. Serum exosomes isolated by ExoQuick precipitations were characterized by transmission electron microscopy, nanoparticle-tracking analysis and western blotting. The levels of exosomal miR-9 and miR-124 were determined by real-time quantitative PCR. Compared with controls, the concentration of serum exosomes and the median levels of serum exosomal miR-9 and miR-124 were significantly higher in AIS patients (p<0.01. The levels of both miR-9 and miR-124 were positively correlated with National Institutes of Health Stroke Scale (NIHSS scores, infarct volumes and serum concentrations of IL-6. The areas under the curve for exosomal miR-9 and miR-124 were 0.8026 and 0.6976, respectively. This proof of concept study suggests that serum exosomal miR-9 and miR-124 are promising biomarkers for diagnosing AIS and evaluating the degree of damage caused by ischemic injury. However, further studies are needed to explore the potential roles of the exosomes released from brain tissues in post stroke complications.

  9. Stroke mimic diagnoses presenting to a hyperacute stroke unit.

    Science.gov (United States)

    Dawson, Ang; Cloud, Geoffrey C; Pereira, Anthony C; Moynihan, Barry J

    2016-10-01

    Stroke services have been centralised in several countries in recent years. Diagnosing acute stroke is challenging and a high proportion of patients admitted to stroke units are diagnosed as a non-stroke condition (stroke mimics). This study aims to describe the stroke mimic patient group, including their impact on stroke services. We analysed routine clinical data from 2,305 consecutive admissions to a stroke unit at St George's Hospital, London. Mimic groupings were derived from 335 individual codes into 17 groupings. From 2,305 admissions, 555 stroke mimic diagnoses were identified (24.2%) and 72% of stroke mimics had at least one stroke risk factor. Common mimic diagnoses were headache, seizure and syncope. Medically unexplained symptoms and decompensation of underlying conditions were also common. Median length of stay was 1 day; a diagnosis of dementia (p=0.028) or needing MRI (p=0.006) was associated with a longer stay. Despite emergency department assessment by specialist clinicians and computed tomography brain, one in four suspected stroke patients admitted to hospital had a non-stroke diagnosis. Stroke mimics represent a heterogeneous patient group with significant impacts on stroke services. Co-location of stroke and acute neurology services may offer advantages where service reorganisation is being considered. © Royal College of Physicians 2016. All rights reserved.

  10. Impact of Shoulder Abduction Loading on Brain-Machine Interface in Predicting Hand Opening and Closing in Individuals With Chronic Stroke.

    Science.gov (United States)

    Yao, Jun; Sheaff, Clay; Carmona, Carolina; Dewald, Julius P A

    2016-05-01

    Many individuals with moderate and severe stroke are unable to use their paretic hand. Currently, the effect of conventional therapy on regaining meaningful hand function in this population is limited. Efforts have been made to use brain-machine interfaces (BMIs) to control hand function. To date, almost all BMI classification algorithms are designed for detecting hand movements with a resting arm. However, many functional movements require simultaneous movements of the arm and hand. Arm movement will possibly affect the detection of intended hand movements, specifically for individuals with chronic stroke who have muscle synergies. The most prevalent upper-extremity synergy-flexor synergy-is expressed as an abnormal coupling between shoulder abductors and elbow/wrist/finger flexors. We hypothesized that because of flexor synergy, shoulder abductor activity would affect the detection of the hand-opening (a movement inhibited by flexion synergy) but not the hand-closing task (a movement facilitated by the flexion synergy). We evaluated the accuracy of a BMI classification algorithm in detecting hand-opening versus closing after reaching a target with 2 different shoulder-abduction loads in 6 individuals with stroke. We found a decreased accuracy in detecting hand opening when an individual with stroke intends to open the hand while activating shoulder abductors. However, such decreased accuracy with increased shoulder loading was not shown while detecting a hand-closing task. This study supports the idea that one should consider the effect of shoulder abduction activity when designing BMI classification algorithms for the purpose of restoring hand function in individuals with moderate to severe stroke. © The Author(s) 2015.

  11. Themes and strategies for studying the biology of stroke recovery in the poststroke epoch.

    Science.gov (United States)

    Carmichael, S Thomas

    2008-04-01

    This review will focus on the emerging principles of neural repair after stroke, and on the overlap between cellular mechanisms of neural repair in stroke and clinical principles of recovery and rehabilitation. Stroke induces axonal sprouting and neurogenesis. Axonal sprouting occurs in tissue adjacent to the stroke and its connected cortical areas, and from sites that are contralateral to the infarct. Neurogenesis produces newly born immature neurons in peri-infarct striatum and cortex. Stimulation of both axonal sprouting and neurogenesis is associated with improved recovery in animal models of stroke. A unique cellular environment in the poststroke brain supports neural repair: an association of angiogenic and remodeling blood vessels with newly born immature neurons in a neurovasclar niche. Controversies in the field of neural repair after stroke persist, and relate to the locations of axonal sprouting in animal models of stroke and how these correlate to patterns of human remapping and recovery, and to the different models of stroke used in studies of neurogenesis. On a cellular level, the phenomenology of neural repair after stroke has been defined and unique regenerative environments in the poststroke brain identified. As the field moves toward specific studies of causal mechanisms in poststroke repair, it will need to maintain a perspective of the animal models suited to the study of neural repair after stroke as they relate to the patterns of recovery in humans in this disease.

  12. Loss of neuron-astroglial interaction rapidly induces protective CNTF expression after stroke in mice

    Science.gov (United States)

    Kang, Seong Su; Keasey, Matthew P.; Cai, Jun; Hagg, Theo

    2012-01-01

    Ciliary neurotrophic factor (CNTF) is a potent neural cytokine with very low expression in the CNS, predominantly by astrocytes. CNTF increases rapidly and greatly following traumatic or ischemic injury. Understanding the underlying mechanisms would help to design pharmacological treatments to increase endogenous CNTF levels for neuroprotection. Here, we show that astroglial CNTF expression in the adult mouse striatum is increased two-fold within 1 hour and increases up to >30 fold over two weeks following a focal stroke caused by a transient middle cerebral artery occlusion (MCAO). Selective neuronal loss caused by intrastriatal injection of quinolinic acid resulted in a comparable increase. Co-cultured neurons reduced CNTF expression in astrocytes which was prevented by light trypsinization. RGD blocking peptides induced CNTF expression which was dependent on transcription. Astroglial CNTF expression was not affected by diffusible neuronal molecules or by neurotransmitters. The transient ischemia does not seem to directly increase CNTF, as intrastriatal injection of an ischemic solution or exposure of naive mice or cultured cells to severe hypoxia had minimal effects. Inflammatory mechanisms were probably also not involved, as intrastriatal injection of pro-inflammatory cytokines (IFNγ, IL6) in naive mice had no or small effects, and anti-inflammatory treatments did not diminish the increase in CNTF after MCAO. CNTF−/− mice had more extensive tissue loss and similar astrocyte activation after MCAO than their wildtype littermates. These data suggest that contact-mediated integrin signaling between neurons and astrocytes normally represses CNTF expression and that neuronal dysfunction causes a rapid protective response by the CNS. PMID:22764235

  13. Brain death induces renal expression of heme oxygenase-1 and heat shock protein 70

    Directory of Open Access Journals (Sweden)

    van Dullemen Leon FA

    2013-01-01

    Full Text Available Abstract Background Kidneys derived from brain dead donors have lower graft survival and higher graft-function loss compared to their living donor counterpart. Heat Shock Proteins (HSP are a large family of stress proteins involved in maintaining cell homeostasis. We studied the role of stress-inducible genes Heme Oxygenase-1 (HO-1, HSP27, HSP40, and HSP70 in the kidney following a 4 hour period of brain death. Methods Brain death was induced in rats (n=6 by inflating a balloon catheter in the epidural space. Kidneys were analysed for HSPs using RT-PCR, Western blotting, and immunohistochemistry. Results RT-PCR data showed a significant increase in gene expression for HO-1 and HSP70 in kidneys of brain dead rats. Western blotting revealed a massive increase in HO-1 protein in brain dead rat kidneys. Immunohistochemistry confirmed these findings, showing extensive HO-1 protein expression in the renal cortical tubules of brain dead rats. HSP70 protein was predominantly increased in renal distal tubules of brain dead rats treated for hypotension. Conclusion Renal stress caused by brain death induces expression of the cytoprotective genes HO-1 and HSP70, but not of HSP27 and HSP40. The upregulation of these cytoprotective genes indicate that renal damage occurs during brain death, and could be part of a protective or recuperative mechanism induced by brain death-associated stress.

  14. In vivo experimental stroke and in vitro organ culture induce similar changes in vasoconstrictor receptors and intracellular calcium handling in rat cerebral arteries

    DEFF Research Database (Denmark)

    Povlsen, Gro Klitgaard; Waldsee, Roya; Ahnstedt, Hilda

    2012-01-01

    Cerebral arteries subjected to different types of experimental stroke upregulate their expression of certain G-protein-coupled vasoconstrictor receptors, a phenomenon that worsens the ischemic brain damage. Upregulation of contractile endothelin B (ET(B)) and 5-hydroxytryptamine 1B (5-HT(1B)) rec...

  15. Family History in Young Patients With Stroke.

    Science.gov (United States)

    Thijs, Vincent; Grittner, Ulrike; Dichgans, Martin; Enzinger, Christian; Fazekas, Franz; Giese, Anne-Katrin; Kessler, Christof; Kolodny, Edwin; Kropp, Peter; Martus, Peter; Norrving, Bo; Ringelstein, Erich Bernd; Rothwell, Peter M; Schmidt, Reinhold; Tanislav, Christian; Tatlisumak, Turgut; von Sarnowski, Bettina; Rolfs, Arndt

    2015-07-01

    Family history of stroke is an established risk factor for stroke. We evaluated whether family history of stroke predisposed to certain stroke subtypes and whether it differed by sex in young patients with stroke. We used data from the Stroke in Fabry Patients study, a large prospective, hospital-based, screening study for Fabry disease in young patients (aged stroke in whom cardiovascular risk factors and family history of stroke were obtained and detailed stroke subtyping was performed. A family history of stroke was present in 1578 of 4232 transient ischemic attack and ischemic stroke patients (37.3%). Female patients more often had a history of stroke in the maternal lineage (P=0.027) than in the paternal lineage. There was no association with stroke subtype according to Trial of Org 10172 in Acute Stroke Treatment nor with the presence of white matter disease on brain imaging. Patients with dissection less frequently reported a family history of stroke (30.4% versus 36.3%; P=0.018). Patients with a parental history of stroke more commonly had siblings with stroke (3.6% versus 2.6%; P=0.047). Although present in about a third of patients, a family history of stroke is not specifically related to stroke pathogenic subtypes in patients with young stroke. Young women with stroke more often report stroke in the maternal lineage. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00414583. © 2015 American Heart Association, Inc.

  16. Exploratory study on the effects of a robotic hand rehabilitation device on changes in grip strength and brain activity after stroke.

    Science.gov (United States)

    Pinter, Daniela; Pegritz, Sandra; Pargfrieder, Christa; Reiter, Gudrun; Wurm, Walter; Gattringer, Thomas; Linderl-Madrutter, Regina; Neuper, Claudia; Fazekas, Franz; Grieshofer, Peter; Enzinger, Christian

    2013-01-01

    The brain mechanisms underlying successful recovery of hand fuenction after stroke are still not fully understood, although functional MRI (fMRI) studies underline the importance of neuronal plasticity. We explored potential changes in brain activity in 7 patients with subacute to chronic stroke (69 ± 8 years) with moderate- to high-grade distal paresis of the upper limb (Motricity Index: 59.4) after standardized robotic finger-hand rehabilitation training, in addition to conventional rehabilitation therapy for 3 weeks. Behavioral and fMRI assessments were carried out before and after training to characterize changes in brain activity and behavior. The Motricity Index (pre: 59.4, post: 67.2, P hand increased significantly after rehabilitation. On fMRI, active movement of the affected (left) hand resulted in contralesional (ie, ipsilateral) activation of the primary sensorimotor cortex prior to rehabilitation. After rehabilitation, activation appeared "normalized," including the ipsilesional primary sensorimotor cortex and supplementary motor area (SMA). No changes and no abnormalities of activation maps were seen during movement of the unaffected hand. Subsequent region-of-interest analyses showed no significant ipsilesional activation increases after rehabilitation. Despite behavioral improvements, we failed to identify consistent patterns of functional reorganization in our sample. This warrants caution in the use of fMRI as a tool to explore neural plasticity in heterogeneous samples lacking sufficient statistical power.

  17. Measuring and Inducing Brain Plasticity in Chronic Aphasia

    Science.gov (United States)

    Fridriksson, Julius

    2011-01-01

    Brain plasticity associated with anomia recovery in aphasia is poorly understood. Here, I review four recent studies from my lab that focused on brain modulation associated with long-term anomia outcome, its behavioral treatment, and the use of transcranial brain stimulation to enhance anomia treatment success in individuals with chronic aphasia…

  18. Design and Optimization of an EEG-Based Brain Machine Interface (BMI) to an Upper-Limb Exoskeleton for Stroke Survivors

    Science.gov (United States)

    Bhagat, Nikunj A.; Venkatakrishnan, Anusha; Abibullaev, Berdakh; Artz, Edward J.; Yozbatiran, Nuray; Blank, Amy A.; French, James; Karmonik, Christof; Grossman, Robert G.; O'Malley, Marcia K.; Francisco, Gerard E.; Contreras-Vidal, Jose L.

    2016-01-01

    This study demonstrates the feasibility of detecting motor intent from brain activity of chronic stroke patients using an asynchronous electroencephalography (EEG)-based brain machine interface (BMI). Intent was inferred from movement related cortical potentials (MRCPs) measured over an optimized set of EEG electrodes. Successful intent detection triggered the motion of an upper-limb exoskeleton (MAHI Exo-II), to guide movement and to encourage active user participation by providing instantaneous sensory feedback. Several BMI design features were optimized to increase system performance in the presence of single-trial variability of MRCPs in the injured brain: (1) an adaptive time window was used for extracting features during BMI calibration; (2) training data from two consecutive days were pooled for BMI calibration to increase robustness to handle the day-to-day variations typical of EEG, and (3) BMI predictions were gated by residual electromyography (EMG) activity from the impaired arm, to reduce the number of false positives. This patient-specific BMI calibration approach can accommodate a broad spectrum of stroke patients with diverse motor capabilities. Following BMI optimization on day 3, testing of the closed-loop BMI-MAHI exoskeleton, on 4th and 5th days of the study, showed consistent BMI performance with overall mean true positive rate (TPR) = 62.7 ± 21.4% on day 4 and 67.1 ± 14.6% on day 5. The overall false positive rate (FPR) across subjects was 27.74 ± 37.46% on day 4 and 27.5 ± 35.64% on day 5; however for two subjects who had residual motor function and could benefit from the EMG-gated BMI, the mean FPR was quite low (BMI for stroke patients can be designed and optimized to perform well across multiple days without system recalibration. PMID:27065787

  19. Improving Stroke Management through Specialized Stroke Units in ...

    African Journals Online (AJOL)

    ... rehabilitation of the stroke patient. The establishment of stroke units has been found to improve the survival of patients and significantly reduce disability by rendering holistic care. Early intervention to rapidly restore and maintain blood supply to the ischemic area in the brain, minimize brain damage and hence impairment ...

  20. Xiao-Xu-Ming Decoction Protects against Blood-Brain Barrier Disruption and Neurological Injury Induced by Cerebral Ischemia and Reperfusion in Rats.

    Science.gov (United States)

    Lan, Rui; Xiang, Jun; Wang, Guo-Hua; Li, Wen-Wei; Zhang, Wen; Xu, Li-Li; Cai, Ding-Fang

    2013-01-01

    Xiao-Xu-Ming decoction (XXMD) is an effective prescription in the treatment of ischemic stroke, but the mechanisms involved are not well known. In the present study, 120 male Sprague-Dawley rats were randomly divided into 5 groups: sham control (sham), ischemia and reperfusion (IR), and IR plus 15, 30, and 60 g/kg/day XXMD. The stroke model was induced by 90 min of middle cerebral artery occlusion followed by reperfusion. The brain lesion areas were evaluated by 2,3,5-triphenyltetrazolium chloride staining, and neurological deficits were observed at different time points after reperfusion. Blood-brain barrier (BBB) disruption was evaluated by assessing brain water content and Evans blue content. Pathological changes in BBB ultrastructure were observed with transmission electron microscopy. MMP-9, -2, and VEGF expression levels were quantitatively determined by western blotting and immunohistochemistry. We found that XXMD (60 g/kg/day) treatment reduced cerebral infarct area, improved behavioral function, and attenuated ultrastructure damage and permeability of BBB following ischemia and reperfusion. Moreover, XXMD downregulated the expression levels of MMP-9, -2, and VEGF. These findings indicate that XXMD alleviates BBB disruption and cerebral ischemic injury, which may be achieved by inhibiting the expression of MMP-9, -2, and VEGF.

  1. Microparticle Shedding from Neural Progenitor Cells and Vascular Compartment Cells Is Increased in Ischemic Stroke.

    Science.gov (United States)

    Chiva-Blanch, Gemma; Suades, Rosa; Crespo, Javier; Peña, Esther; Padró, Teresa; Jiménez-Xarrié, Elena; Martí-Fàbregas, Joan; Badimon, Lina

    2016-01-01

    Ischemic stroke has shown to induce platelet and endothelial microparticle shedding, but whether stroke induces microparticle shedding from additional blood and vascular compartment cells is unclear. Neural precursor cells have been shown to replace dying neurons at sites of brain injury; however, if neural precursor cell activation is associated to microparticle shedding, and whether this activation is maintained at long term and associates to stroke type and severity remains unknown. We analyzed neural precursor cells and blood and vascular compartment cells microparticle shedding after an acute ischemic stroke. Forty-four patients were included in the study within the first 48h after the onset of stroke. The cerebral lesion size was evaluated at 3-7 days of the stroke. Circulating microparticles from neural precursor cells and blood and vascular compartment cells (platelets, endothelial cells, erythrocytes, leukocytes, lymphocytes, monocytes and smooth muscle cells) were analyzed by flow cytometry at the onset of stroke and at 7 and 90 days. Forty-four age-matched high cardiovascular risk subjects without documented vascular disease were used as controls. Compared to high cardiovascular risk controls, patients showed higher number of neural precursor cell- and all blood and vascular compartment cell-derived microparticles at the onset of stroke, and after 7 and 90 days. At 90 days, neural precursor cell-derived microparticles decreased and smooth muscle cell-derived microparticles increased compared to levels at the onset of stroke, but only in those patients with the highest stroke-induced cerebral lesions. Stroke increases blood and vascular compartment cell and neural precursor cell microparticle shedding, an effect that is chronically maintained up to 90 days after the ischemic event. These results show that stroke induces a generalized blood and vascular cell activation and the initiation of neuronal cell repair process after stroke. Larger cerebral lesions

  2. Effect of prophylactic hyperbaric oxygen treatment for radiation-induced brain injury after stereotactic radiosurgery of brain metastases

    International Nuclear Information System (INIS)

    Ohguri, Takayuki; Imada, Hajime; Kohshi, Kiyotaka; Kakeda, Shingo; Ohnari, Norihiro; Morioka, Tomoaki; Nakano, Keita; Konda, Nobuhide; Korogi, Yukunori

    2007-01-01

    Purpose: The purpose of the present study was to evaluate the prophylactic effect of hyperbaric oxygen (HBO) therapy for radiation-induced brain injury in patients with brain metastasis treated with stereotactic radiosurgery (SRS). Methods and Materials: The data of 78 patients presenting with 101 brain metastases treated with SRS between October 1994 and September 2003 were retrospectively analyzed. A total of 32 patients with 47 brain metastases were treated with prophylactic HBO (HBO group), which included all 21 patients who underwent subsequent or prior radiotherapy and 11 patients with common predictors of longer survival, such as inactive extracranial tumors and younger age. The other 46 patients with 54 brain metastases did not undergo HBO (non-HBO group). Radiation-induced brain injuries were divided into two categories, white matter injury (WMI) and radiation necrosis (RN), on the basis of imaging findings. Results: Radiation-induced brain injury occurred in 5 lesions (11%) in the HBO group (2 WMIs and 3 RNs) and in 11 (20%) in the non-HBO group (9 WMIs and 2 RNs). The WMI was less frequent for the HBO group than for the non-HBO group (p = 0.05), although multivariate analysis by logistic regression showed that WMI was not significantly correlated with HBO (p = 0.07). The 1-year actuarial probability of WMI was significantly better for the HBO group (2%) than for the non-HBO group (36%) (p < 0.05). Conclusions: The present study showed a potential value of prophylactic HBO for Radiation-induced WMIs, which justifies further evaluation to confirm its definite benefit

  3. Principles of Motor Recovery in Post-Stroke Patients using Hand Exoskeleton Controlled by the Brain-Computer Interface Based on Motor Imagery

    Czech Academy of Sciences Publication Activity Database

    Frolov, A. A.; Húsek, Dušan; Biryukova, E. V.; Bobrov, P.; Mokienko, O.; Alexandrov, A.V.

    2017-01-01

    Roč. 27, č. 1 (2017), s. 107-137 ISSN 1210-0552 Grant - others:Russian Ministry of Education and Science(RU) RFMEFI60715X0128 Institutional support: RVO:67985807 Keywords : brain computer interface * motor imagery * post-stroke and post-traumatic patients * arm and hand exoskeleton * proportional derivative controller * motor synergy * clinical application Subject RIV: IN - Informatics, Computer Science OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 0.394, year: 2016

  4. THE USE OF A COMPLEX “BRAIN-COMPUTER INTERFACE AND EXO-SKELETON” AND MOVEMENT IMAGINATION TECHNIQUE FOR POST-STROKE REHABILITATION

    Directory of Open Access Journals (Sweden)

    S. V. Kotov

    2015-01-01

    Full Text Available Background: Efficacy of physical exercise and movement imagination for restoration of motor dysfunction after a stroke is seen as proven. However, the use of movement imagination is complicated by impossibility of objective and subjective control over  the exercise, as well as by the absence of their motor support. The brain-computer interface based on electroencephalography is a technique that enables a feedback during movement imagination.Materials and methods: We assessed 10 patients (6 men and 4 women aged from 30 to 66 years (mean age, 47 ± 7.7 years with an ischemic (n = 9 and hemorrhagic (n = 1 stroke during the last 2 months to 4 years. Online recognition of movement imagination was done by a classifier with a brain computer interface. An exo-skeleton supported passive movements in a paretic hand managed by the brain-computer interface. During 2 weeks the patients had 10 sessions of 45–90 minute duration each. For control, we used data from 5 stroke patients who, in addition to their standard treatment, underwent an imitation of rehabilitation procedures without movement imagination and feedback. To assess efficacy of treatment, we used a modified Ashworth scale, Fugl-Meyer scale, test for evaluation of hand functions ARAT, British scale for assessment of muscle force MRC-SS. Level of everyday activity and working ability was measured with a modified Rankin scale and Bartel index. Cognitive functions were assessed with Schulte tables.Results: Online recognition of movement imagination according to desynchronization of μ rhythm was registered in 50–75% of patients. All patients reported a subjective improvement of motor functions and working ability. Positive results for at least one parameter were observed in all patients; however, there were no significant difference between the parameters before and after rehabilitation procedures, excluding cognitive functions (degree of warming-up, p < 0.02.Conclusion: In post stroke patients

  5. Innate Immunity and Inflammation Post-Stroke: An α7-Nicotinic Agonist Perspective

    Directory of Open Access Journals (Sweden)

    Silke Neumann

    2015-12-01

    Full Text Available Stroke is one of the leading causes of death and long-term disability, with limited treatment options available. Inflammation contributes to damage tissue in the central nervous system across a broad range of neuropathologies, including Alzheimer’s disease, pain, Schizophrenia, and stroke. While the immune system plays an important role in contributing to brain damage produced by ischemia, the damaged brain, in turn, can exert a powerful immune-suppressive effect that promotes infections and threatens the survival of stroke patients. Recently the cholinergic anti-inflammatory pathway, in particular its modulation using α7-nicotinic acetylcholine receptor (α7-nAChR ligands, has shown potential as a strategy to dampen the inflammatory response and facilitate functional recovery in stroke patients. Here we discuss the current literature on stroke-induced inflammation and the effects of α7-nAChR modulators on innate immune cells.

  6. Neuroimaging Correlates of Post-Stroke Aphasia Rehabilitation in a Pilot Randomized Trial of Constraint-Induced Aphasia Therapy.

    Science.gov (United States)

    Nenert, Rodolphe; Allendorfer, Jane B; Martin, Amber M; Banks, Christi; Ball, Angel; Vannest, Jennifer; Dietz, Aimee R; Szaflarski, Jerzy P

    2017-07-18

    BACKGROUND Recovery from post-stroke aphasia is a long and complex process with an uncertain outcome. Various interventions have been proposed to augment the recovery, including constraint-induced aphasia therapy (CIAT). CIAT has been applied to patients suffering from post-stroke aphasia in several unblinded studies to show mild-to-moderate linguistic gains. The aim of the present study was to evaluate the neuroimaging correlates of CIAT in patients with chronic aphasia related to left middle cerebral artery stroke. MATERIAL AND METHODS Out of 24 patients recruited in a pilot randomized blinded trial of CIAT, 19 patients received fMRI of language. Eleven of them received CIAT (trained) and eight served as a control group (untrained). Each patient participated in three fMRI sessions (before training, after training, and 3 months later) that included semantic decision and verb generation fMRI tasks, and a battery of language tests. Matching healthy control participants were also included (N=38; matching based on age, handedness, and sex). RESULTS Language testing showed significantly improved performance on Boston Naming Test (BNT; paphasia with no specific effect from CIAT training.

  7. ECT: its brain enabling effects. A review of electroconvulsive therapy-induced structural brain plasticity

    NARCIS (Netherlands)

    Bouckaert, F.; Sienaert, P.; Obbels, J.; Dols, A.; Vandenbulcke, M.; Stek, M.L.; Bolwig, T.

    2014-01-01

    BACKGROUND: Since the past 2 decades, new evidence for brain plasticity has caused a shift in both preclinical and clinical ECT research from falsifying the "brain damage hypothesis" toward exploring ECT's enabling brain (neuro)plasticity effects. METHODS: By reviewing the available animal and human

  8. Immune interventions in stroke

    Science.gov (United States)

    Fu, Ying; Liu, Qiang; Anrather, Josef

    2016-01-01

    Inflammatory and immune responses in the brain can shape the clinical presentation and outcome of stroke. Approaches for effective management of acute stroke are sparse and many measures for brain protection fail, but our ability to modulate the immune system and modify the disease progression of multiple sclerosis is increasing. As a result, immune interventions are currently being explored as therapeutic interventions in acute stroke. In this Review, we compare the immunological features of acute stroke with those of multiple sclerosis, identify unique immunological features of stroke, and consider the evidence for immune interventions. In acute stroke, microglia activation and cell death products trigger an inflammatory cascade that damages vessels and the parenchyma within minutes to hours of the ischaemia or haemorrhage. Immune interventions that restrict brain inflammation, vascular permeability and tissue oedema must be administered rapidly to reduce acute immune-mediated destruction and to avoid subsequent immunosuppression. Preliminary results suggest that the use of drugs that modify disease in multiple sclerosis might accomplish these goals in ischaemic and haemorrhagic stroke. Further elucidation of the immune mechanisms involved in stroke is likely to lead to successful immune interventions. PMID:26303850

  9. Study to assess the effectiveness of modified constraint-induced movement therapy in stroke subjects: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Priyanka Singh

    2013-01-01

    Full Text Available Background and Purpose: The purpose of this study was to assess the effectiveness of modified constraint induced movement therapy (m-CIMT in stroke subjects. Materials and Methods: A total of forty sub-acute stroke subjects were randomly assigned to either a m-CIMT (n = 20 or in a control group (n = 20. The m-CIMT group (14 men, 6 women; mean age = 55.2 years consisted of structured 2 h therapy sessions emphasizing affected arm use, occurring 5 times/week for 2 weeks. A mitt was used to restrain the unaffected arm for 10 h/day for 2 week. The control group (11 men, 9 women; mean age = 56.4 years consisted of conventional rehabilitation for time-matched exercise program. The outcome measures were evaluated at pre- and post-intervention by using the Wolf Motor Function Test (WMFT and Fugl-Meyer assessment (FMA of motor recovery after stroke. Results: After intervention significant effects were observed in m-CIMT group on WMFT (pre-test and post-test score was 28.04 ± 6.58, 13.59 ± 2.86; P =0.003. Similarly on FMA (pre- and post-test score was 31.15 ± 6.37, 55.7 ± 6.4; P = 0.00. Conclusion: There is a significant improvem ent in upper extremity function so it indicates that m-CIMT is effective in improving the motor function of the affected arm in stroke subjects. However, its long-term effect has not proved since there was no follow-up after intervention.

  10. CSF transthyretin neuroprotection in a mouse model of brain ischemia

    DEFF Research Database (Denmark)

    Santos, Sofia Duque; Lambertsen, Kate Lykke; Clausen, Bettina Hjelm

    2010-01-01

    Brain injury caused by ischemia is a major cause of human mortality and physical/cognitive disability worldwide. Experimentally, brain ischemia can be induced surgically by permanent middle cerebral artery occlusion. Using this model, we studied the influence of transthyretin in ischemic stroke. ...

  11. BHT blocks NF-kappaB activation and ethanol-induced brain damage.

    Science.gov (United States)

    Crews, Fulton; Nixon, Kimberly; Kim, Daniel; Joseph, James; Shukitt-Hale, Barbara; Qin, Liya; Zou, Jian

    2006-11-01

    Binge ethanol administration causes corticolimbic brain damage that models alcoholic neurodegeneration. The mechanism of binge ethanol-induced degeneration is unknown, but is not simple glutamate-N-methyl-D-aspartate (NMDA) excitotoxicity. To test the hypothesis that oxidative stress and inflammation are mechanisms of binge ethanol-induced brain damage, we administered 4 antioxidants, e.g., butylated hydroxytoluene (BHT), ebselen (Eb), vitamin E (VE), and blueberry (BB) extract, during binge ethanol treatment and assessed various measures of neurodegeneration. Adult Sprague-Dawley rats were treated with intragastric ethanol 3 times per day (8-12 g/kg/d) alone or in combination with antioxidants or isocaloric diet for 4 days. Animals were killed, and brains were perfused and extracted for histochemical silver stain determination of brain damage, markers of neurogenesis, or other immunohistochemistry. Some animals were used for determination of nuclear factor kappa B (NF-kappaB)-DNA binding by electrophoretic mobility shift assay (EMSA) or for reverse transcription-polymerase chain reaction (RT-PCR) of cyclooxygenase 2 (COX2). Binge ethanol induced corticolimbic brain damage and reduced neurogenesis. Treatment with BHT reversed binge induced brain damage and blocked ethanol inhibition of neurogenesis in all regions studied. Interestingly, the other antioxidants studied, e.g., Eb, VE, and BB, did not protect against binge-induced brain damage. Binge ethanol treatment also caused microglia activation, increased NF-kappaB-DNA binding and COX2 expression. Butylated hydroxytoluene reduced binge-induced NF-kappaB-DNA binding and COX2 expression. Binge-induced brain damage and activation of NF-kappaB-DNA binding are blocked by BHT. These studies support a neuroinflammatory mechanism of binge ethanol-induced brain damage.

  12. Tunicamycin-induced unfolded protein response in the developing mouse brain

    International Nuclear Information System (INIS)

    Wang, Haiping; Wang, Xin; Ke, Zun-Ji; Comer, Ashley L.; Xu, Mei; Frank, Jacqueline A.; Zhang, Zhuo; Shi, Xianglin; Luo, Jia

    2015-01-01

    Accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) causes ER stress, resulting in the activation of the unfolded protein response (UPR). ER stress and UPR are associated with many neurodevelopmental and neurodegenerative disorders. The developing brain is particularly susceptible to environmental insults which may cause ER stress. We evaluated the UPR in the brain of postnatal mice. Tunicamycin, a commonly used ER stress inducer, was administered subcutaneously to mice of postnatal days (PDs) 4, 12 and 25. Tunicamycin caused UPR in the cerebral cortex, hippocampus and cerebellum of mice of PD4 and PD12, which was evident by the upregulation of ATF6, XBP1s, p-eIF2α, GRP78, GRP94 and MANF, but failed to induce UPR in the brain of PD25 mice. Tunicamycin-induced UPR in the liver was observed at all stages. In PD4 mice, tunicamycin-induced caspase-3 activation was observed in layer II of the parietal and optical cortex, CA1–CA3 and the subiculum of the hippocampus, the cerebellar external germinal layer and the superior/inferior colliculus. Tunicamycin-induced caspase-3 activation was also shown on PD12 but to a much lesser degree and mainly located in the dentate gyrus of the hippocampus, deep cerebellar nuclei and pons. Tunicamycin did not activate caspase-3 in the brain of PD25 mice and the liver of all stages. Similarly, immature cerebellar neurons were sensitive to tunicamycin-induced cell death in culture, but became resistant as they matured in vitro. These results suggest that the UPR is developmentally regulated and the immature brain is more susceptible to ER stress. - Highlights: • Tunicamycin caused a development-dependent UPR in the mouse brain. • Immature brain was more susceptible to tunicamycin-induced endoplasmic reticulum stress. • Tunicamycin caused more neuronal death in immature brain than mature brain. • Tunicamycin-induced neuronal death is region-specific

  13. Tunicamycin-induced unfolded protein response in the developing mouse brain

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Haiping; Wang, Xin [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Ke, Zun-Ji [Department of Biochemistry, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203 (China); Comer, Ashley L.; Xu, Mei; Frank, Jacqueline A. [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Zhang, Zhuo; Shi, Xianglin [Graduate Center for Toxicology, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Luo, Jia, E-mail: jialuo888@uky.edu [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States)

    2015-03-15

    Accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) causes ER stress, resulting in the activation of the unfolded protein response (UPR). ER stress and UPR are associated with many neurodevelopmental and neurodegenerative disorders. The developing brain is particularly susceptible to environmental insults which may cause ER stress. We evaluated the UPR in the brain of postnatal mice. Tunicamycin, a commonly used ER stress inducer, was administered subcutaneously to mice of postnatal days (PDs) 4, 12 and 25. Tunicamycin caused UPR in the cerebral cortex, hippocampus and cerebellum of mice of PD4 and PD12, which was evident by the upregulation of ATF6, XBP1s, p-eIF2α, GRP78, GRP94 and MANF, but failed to induce UPR in the brain of PD25 mice. Tunicamycin-induced UPR in the liver was observed at all stages. In PD4 mice, tunicamycin-induced caspase-3 activation was observed in layer II of the parietal and optical cortex, CA1–CA3 and the subiculum of the hippocampus, the cerebellar external germinal layer and the superior/inferior colliculus. Tunicamycin-induced caspase-3 activation was also shown on PD12 but to a much lesser degree and mainly located in the dentate gyrus of the hippocampus, deep cerebellar nuclei and pons. Tunicamycin did not activate caspase-3 in the brain of PD25 mice and the liver of all stages. Similarly, immature cerebellar neurons were sensitive to tunicamycin-induced cell death in culture, but became resistant as they matured in vitro. These results suggest that the UPR is developmentally regulated and the immature brain is more susceptible to ER stress. - Highlights: • Tunicamycin caused a development-dependent UPR in the mouse brain. • Immature brain was more susceptible to tunicamycin-induced endoplasmic reticulum stress. • Tunicamycin caused more neuronal death in immature brain than mature brain. • Tunicamycin-induced neuronal death is region-specific.

  14. The role of dual energy CT in differentiating between brain haemorrhage and contrast medium after mechanical revascularisation in acute ischaemic stroke

    International Nuclear Information System (INIS)

    Tijssen, M.P.M.; Stadler, A.A.R.; Zwam, W. van; Graaf, R. de; Postma, A.A.; Hofman, P.A.M.; Oostenbrugge, R.J. van; Klotz, E.; Wildberger, J.E.

    2014-01-01

    To assess the feasibility of dual energy computed tomography (DE-CT) in intra-arterially treated acute ischaemic stroke patients to discriminate between contrast extravasation and intracerebral haemorrhage. Thirty consecutive acute ischaemic stroke patients following intra-arterial treatment were examined with DE-CT. Simultaneous imaging at 80 kV and 140 kV was employed with calculation of mixed images. Virtual unenhanced non-contrast (VNC) images and iodine overlay maps (IOM) were calculated using a dedicated brain haemorrhage algorithm. Mixed images alone, as ''conventional CT'', and DE-CT interpretations were evaluated and compared with follow-up CT. Eight patients were excluded owing to a lack of follow-up or loss of data. Mixed images showed intracerebral hyperdense areas in 19/22 patients. Both haemorrhage and residual contrast material were present in 1/22. IOM suggested contrast extravasation in 18/22 patients; in 16/18 patients this was confirmed at follow-up. The positive predictive value (PPV) of mixed imaging alone was 25 %, with a negative predictive value (NPV) of 91 % and accuracy of 63 %. The PPV for detection of haemorrhage with DE-CT was 100 %, with an NPV of 89 % and accuracy improved to 89 %. Dual energy computed tomography improves accuracy and diagnostic confidence in early differentiation between intracranial haemorrhage and contrast medium extravasation in acute stroke patients following intra-arterial revascularisation. (orig.)

  15. Acupuncture at Waiguan (SJ5) and sham points influences activation of functional brain areas of ischemic stroke patients: a functional magnetic resonance imaging study.

    Science.gov (United States)

    Qi, Ji; Chen, Junqi; Huang, Yong; Lai, Xinsheng; Tang, Chunzhi; Yang, Junjun; Chen, Hua; Qu, Shanshan

    2014-02-01

    Most studies addressing the specificity of meridians and acupuncture points have focused mainly on the different neural effects of acupuncture at different points in healthy individuals. This study examined the effects of acupuncture on brain function in a pathological context. Sixteen patients with ischemic stroke