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Thrombolysis is the most effective therapy for ischaemic stroke. The current guidelines and approvals have limited its use to patients available for treatment within 4.5 hours of onset and those aged 80 or less. There are also a number of other limitations derived from clinical trial protocols, i.e. minor and major strokes. The available evidence has indicated its possible efficacy in patients treated within 6 hours of onset and not fulfilling other limitations.Last year, the results of the IST-3 (Third International Stroke Trial: Thrombolysis) and a meta-analysis of all available trials including IST-3 were published. They point out the possible benefit of thrombolysis in patients not meeting the current criteria, which has been acknowledged in the Polish guidelines for management of stroke.  相似文献   
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Introduction: The purpose of our study was to examine relations among spasticity, weakness, force variability, and sustained spontaneous motor unit discharges in spastic–paretic biceps brachii muscles in chronic stroke. Methods: Ten chronic stroke subjects produced submaximal isometric elbow flexion force on impaired and non‐impaired sides. Intramuscular EMG (iEMG) was recorded from biceps and triceps brachii muscles. Results: We observed sustained spontaneous motor unit discharges in resting biceps on iEMG. Spontaneous discharges increased after voluntary activation only on the impaired side. The impaired side had greater matching errors and greater fluctuations in isometric force. Spontaneous discharges were not related functionally to spasticity, force variability, or weakness. However, greater strength on the impaired side correlated with less force variability. Conclusion: Weakness rather than spasticity is a main factor interfering with voluntary force control in paretic–spastic biceps brachii muscles in chronic stroke. Muscle Nerve, 2013  相似文献   
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ABSTRACT

Objective: The aim of this study was to evaluate the potential molecular mechanism of resveratrol (RSV) that attenuates brain damage from focal cerebral ischemia.

Methods and materials: To investigate whether phosphatidylinositol 3-kinase/Akt (PI3K/Akt) pathway was involved in RSV anti-inflammatory and neuroprotective properties. Middle cerebral artery occlusion (MCAO) animal model was used in this study. Adult male Sprague–Dawley (SD) rats underwent MCAO, and then received treatment with RSV or vehicle after the onset of ischemia. PI3K inhibitor LY294002 was injected intracerebroventricularly to inhibit the PI3K/Akt signaling pathway. Neurological deficit scores and cerebral water content were assessed 24 h after MCAO. The inflammatory factors interleukin (IL)-1β, tumor necrosis factor (TNFα), and cyclooxygenase-2 (COX2) mRNA level were examined by real-time PCR. The enzymatic activity of myeloperoxidase (MPO) was measured 24 h after MCAO. The protein expression of phospho-Akt and COX2 in ischemic brain were determined by western blot.

Results: RSV significantly reduced neurological deficit scores, cerebral water content and the enzymatic activity of MPO, all of which were abolished by LY294002 administration. Real-time PCR showed that RSV significantly suppressed the upregulation of the inflammatory factors IL-1β, TNFα, COX2 mRNA levels. RSV significantly inhibited upregulated the protein expression of COX2 24 h after MCAO, which effect was abolished by LY294002 administration.

Conclusion: RSV attenuated ischemic brain damage induced by cerebral artery occlusion mainly through PI3K/Akt signaling pathway.

Abbreviation: MCAO: Middle cerebral artery occlusion; RSV: resveratrol; PI3K/Akt: phosphatidylinositol 3-kinase/Akt; TNF: tumor necrosis factor; COX2: cyclooxygenase-2; MPO: myeloperoxidase; IL: interleukin.  相似文献   
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ABSTRACT

Objectives: Inflammation plays a key role in the pathogenesis and progression of ischemic stroke (IS). The high mobility group box 1 (HMGB1) nucleoprotein is involved in the amplification of inflammatory responses during acute ischemic injury. HMGB1 levels in patients with active disease are higher than those in healthy controls. We performed a meta-analysis to assess currently published data pertaining to circulating blood HMGB1 levels in IS and the relationship with stroke severity.

Methods: We systematically searched for studies investigating the circulating blood HMGB1 levels in patients with IS in PubMed/Medline, Embase, the Cochrane Library, Web of science and China National Knowledge Infrastructure (CNKI). Two independent researchers used the Cochrane Collaboration tools for data extraction and quality assessment. Extracted data were analyzed by Review Manager version 5.3.

Results: A total of 28 studies were included with a total of 4497 participants, including 2671 IS patients and 1826 matched controls. The meta-analysis revealed that compared with control, IS patients had higher circulating blood HMGB1 levels (n = 4497, standardized mean difference (SMD) = 5.70, 95%confidence interval (CI) = 4.79 to 6.62, Z = 12.23, P < 0.00001), and the HMGB1 level was positively correlated with severity (n = 507, SMD = ?2.12, 95%CI = ?3.41 to ?0.82, Z = 3.20, P < 0.00001) and infarct volume (n = 582, 95%CI = ?4.06 to ?1.70, Z = 4.79, P < 0.00001).

Conclusions: This meta-analysis demonstrates that circulating blood HMGB1 levels elevate in IS and higher HMGB1 levels may indicate a more serious condition.  相似文献   
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ABSTRACT

Background: The patterns and mechanisms underlying stroke in cancer patients differ from those of the conventional etiology. In this study, we further investigated the characteristics distinguishing cancer-associated ischemic stroke (CAIS) and the relationship of D-dimer value with CAIS.

Methods: Sixty-one acute ischemic stroke patients with cancer (cancer group) and 76 stroke patients without cancer (control group) were recruited. Cerebrovascular distribution was divided into 3 circulations and 23 vascular territories, and acute multiple brain infarcts (AMBIs) were defined as discrete MRI diffusion-weighted imaging (DWI) lesions in >1 vascular territory.

Results: Cancer patients had higher average D-dimer and fibrinogen degradation product values, and fewer stroke risk factors. The numbers of infarct-affected vascular territories, AMBIs, and AMBIs in multiple circulations were significantly higher in the cancer group. Receiver operating characteristic analysis showed that the cutoff value of D-dimer was 2.785 μg/ml; and above features were particularly evident in cancer patients whose D-dimer values were >2.785 μg/ml, while those with D-dimer values ≤2.785 μg/ml were similar to controls.

Conclusions: D-dimer >2.785 μg/ml may be an effective cutoff value and a sensitive index for identifying CAIS patients. AMBIs in ≥3 vascular territories and AMBIs in both the anterior and posterior circulations are two imaging characteristics of CAIS.  相似文献   
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Activation of protein kinase C? (PKC?) confers protection against neuronal ischemia/reperfusion. Activation of PKC? leads to its translocation to multiple intracellular sites, so a mitochondria‐selective PKC? activator was used to test the importance of mitochondrial activation to the neuroprotective effect of PKC?. PKC? can regulate key cytoprotective mitochondrial functions, including electron transport chain activity, reactive oxygen species (ROS) generation, mitochondrial permeability transition, and detoxification of reactive aldehydes. We tested the ability of mitochondria‐selective activation of PKC? to protect primary brain cell cultures or mice subjected to ischemic stroke. Pretreatment with either general PKC? activator peptide, TAT‐Ψ?RACK, or mitochondrial‐selective PKC? activator, TAT‐Ψ?HSP90, reduced cell death induced by simulated ischemia/reperfusion in neurons, astrocytes, and mixed neuronal cultures. The protective effects of both TAT‐Ψ?RACK and TAT‐Ψ?HSP90 were blocked by the PKC? antagonist ?V1–2, indicating that protection requires PKC? interaction with its anchoring protein, TAT‐?RACK. Further supporting a mitochondrial mechanism for PKC?, neuroprotection by TAT‐Ψ?HSP90 was associated with a marked delay in mitochondrial membrane depolarization and significantly attenuated ROS generation during ischemia. Importantly, TAT‐Ψ?HSP90 reduced infarct size and reduced neurological deficit in C57/BL6 mice subjected to middle cerebral artery occlusion and 24 hr of reperfusion. Thus selective activation of mitochondrial PKC? preserves mitochondrial function in vitro and improves outcome in vivo, suggesting potential therapeutic value clinically when brain ischemia is anticipated, including neurosurgery and cardiac surgery. © 2013 Wiley Periodicals, Inc.  相似文献   
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Functional recovery from injuries to the brain or spinal cord represents a major clinical challenge. The transplantation of stem cells, traditionally isolated from embryonic tissue, may help to reduce damage following such events and promote regeneration and repair through both direct cell replacement and neurotrophic mechanisms. However, the therapeutic potential of using embryonic stem/progenitor cells is significantly restricted by the availability of embryonic tissues and associated ethical issues. Populations of stem cells reside within the dental pulp, representing an alternative source of cells that can be isolated with minimal invasiveness, and thus should illicit fewer moral objections, as a replacement for embryonic/fetal‐derived stem cells. Here we discuss the similarities between dental pulp stem cells (DPSCs) and the endogenous stem cells of the central nervous system (CNS) and their ability to differentiate into neuronal cell types. We also consider in vitro and in vivo studies demonstrating the ability of DPSCs to help protect against and repair neuronal damage, suggesting that dental pulp may provide a viable alternative source of stem cells for replacement therapy following CNS damage. © 2013 Wiley Periodicals, Inc.  相似文献   
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