Science.gov

Sample records for experimental stroke severity

  1. Sleep deprivation attenuates experimental stroke severity in rats.

    PubMed

    Moldovan, Mihai; Constantinescu, Alexandra Oana; Balseanu, Adrian; Oprescu, Nicoleta; Zagrean, Leon; Popa-Wagner, Aurel

    2010-03-01

    Indirect epidemiological and experimental evidence suggest that the severity of injury during stroke is influenced by prior sleep history. The aim of our study was to test the effect of acute sleep deprivation on early outcome following experimental stroke. Young male Sprague-Dawley rats (n=20) were subjected to focal cerebral ischemia by reversible right middle cerebral artery occlusion (MCAO) for 90 min. In 10 rats, MCAO was performed just after 6-h of total sleep deprivation (TSD) by "gentle handling", whereas the other rats served as controls. Neurological function during the first week after stroke was monitored using a battery of behavioral tests investigating the asymmetry of sensorimotor deficit (tape removal test and cylinder test), bilateral sensorimotor coordination (rotor-rod and Inclined plane) and memory (T-maze and radial maze). Following MCAO, control rats had impaired behavioral performance in all tests. The largest impairment was noted in the tape test where the tape removal time from the left forelimb (contralateral to MCAO) was increased by approximately 10 fold (p<0.01). In contrast, rats subjected to TSD had complete recovery of sensorimotor performance consistent with a 2.5 fold smaller infarct volume and reduced morphological signs of neuronal injury at day 7 after MCAO. Our data suggest that brief TSD induces a neuroprotective response that limits the severity of a subsequent stroke, similar to rapid ischemic preconditioning. PMID:20045410

  2. Pre-stroke living situation and depression contribute to initial stroke severity and stroke recovery

    PubMed Central

    Aron, Abraham W.; Staff, Ilene; Fortunato, Gilbert; McCullough, Louise D.

    2014-01-01

    Substantial evidence from both experimental and clinical studies has demonstrated that social isolation can increase stroke incidence and impair recovery. Social isolation leads to higher rates of recurrent stroke but is often not reported as a risk factor. We examined prospectively collected stroke center database variables, which included pre-stroke living situation, to determine if social isolation could be determined from existing data using living arrangement as a proxy. Patients were categorized into 4 groups hypothesized to represent increasing levels of social isolation: Living with Spouse, Living with Family, Living alone with visiting services and Living Alone. Initial stroke severity and recovery were measured using the National Institutes of Health Stroke Scale and Barthel Index, respectively. A multivariate model was used to determine the relationship between pre-stroke living situation, stroke severity and functional outcome. Patients living alone had less severe strokes on admission and better recovery at 3 months compared to the other cohorts. Patients living alone or those that lived with a spouse had less severe strokes on presentation and better recovery at both 3 and 12 months after stroke compared to the other cohorts. However, upon detailed examination, it was found that these patients also had significantly higher pre-stroke function. Pre-existing depression was significantly higher in women and depressed patients had poorer outcomes 3 months after stroke. Information regarding isolation is notably absent from most large stroke databases. A more comprehensive evaluation of social interaction should be obtained to more accurately measure social isolation. PMID:25524014

  3. Prestroke living situation and depression contribute to initial stroke severity and stroke recovery.

    PubMed

    Aron, Abraham W; Staff, Ilene; Fortunato, Gilbert; McCullough, Louise D

    2015-02-01

    Substantial evidence from both experimental and clinical studies has demonstrated that social isolation can increase stroke incidence and impair recovery. Social isolation leads to higher rates of recurrent stroke but is often not reported as a risk factor. We examined prospectively collected stroke center database variables, which included prestroke living situation, to determine if social isolation could be determined from existing data using living arrangement as a proxy. Patients were categorized into 4 groups hypothesized to represent increasing levels of social isolation: living with spouse, living with family, living alone with visiting services, and living alone. Initial stroke severity and recovery were measured using the National Institutes of Health Stroke Scale and Barthel Index, respectively. A multivariate model was used to determine the relationship among prestroke living situation, stroke severity, and functional outcome. Patients living alone had less severe strokes on admission and better recovery at 3 months compared with the other cohorts. Patients living alone or those who lived with a spouse had less severe strokes on presentation and better recovery at both 3 and 12 months after stroke compared with the other cohorts. However, on detailed examination, it was found that these patients also had significantly higher prestroke function. Pre-existing depression was significantly higher in women, and depressed patients had poorer outcomes 3 months after stroke. Information regarding isolation is notably absent from most large stroke databases. A more comprehensive evaluation of social interaction should be obtained to more accurately measure social isolation.

  4. Severe stroke: which medicine for which results?

    PubMed

    Woimant, F; Biteye, Y; Chaine, P; Crozier, S

    2014-02-01

    In face of any severe stroke, the questions for health professionals in charge of the patient are: will the handicap be acceptable for the patient? But can we predict an acceptable handicap for the patient? For his family? When we know that the cognitive disorders, consequences of severe stroke often modify, in a major way, the behaviour of these patients? Given these difficulties for estimate vital and functional prognosis and even more the quality of life of patients with severe stroke, collective reflexions between physicians and nurses are essential, reflexions taking into account preferences and values of patients. Use of resuscitation resources for severe stroke patients implies to offer them the best rehabilitation. So, questions about health pathways for severe stroke are essential: which structures for these patients, which technologies, which medical, medico-social and social supports, which human accompaniment the society can propose to the patients and to their family, so that they have an acceptable quality of life.

  5. Sex Disparities in Stroke: Women Have More Severe Strokes but Better Survival Than Men

    PubMed Central

    Dehlendorff, Christian; Andersen, Klaus Kaae; Olsen, Tom Skyhøj

    2015-01-01

    Background Uncertainty remains about whether stroke affects men and women similarly. We studied differences between men and women with regard to stroke severity and survival. Methods and Results We used the Danish Stroke Registry, with information on all hospital admissions for stroke in Denmark between 2003 and 2012 (N=79 617), and the Danish Register of Causes of Death. Information was available on age, sex, marital status, stroke severity, stroke subtype, socioeconomic status, and cardiovascular risk profile. We studied only deaths due to the index stroke, with the assumption that death reported on death certificates as due to stroke was related to the index stroke if death occurred within the first week or month after stroke. Multivariate Cox regression analysis and multiple imputation were applied. Stroke was the cause of death for 4373 and 5512 of the 79 617 patients within 1 week (5.5%) or 1 month (6.9%), respectively. After the age of 60 years, women had more severe strokes than men. Up to ages in the mid-60s, no difference in the risk of death from stroke was seen between the 2 sexes. For people aged >65 years, however, the risk gradually became greater in men than in women and significantly so (>15%) from the mid-70s (adjusted for age, marital status, stroke severity, stroke subtype, socioeconomic status, and cardiovascular risk factors). Results were essentially the same when analyzing deaths within 1 week, 1 month and ischemic and hemorrhagic stroke separately. Conclusions Stroke affects women and men differently. Elderly women were affected more severely than elderly men but were more likely to survive. PMID:26150479

  6. Mitochondrial Impairment in Cerebrovascular Endothelial Cells is Involved in the Correlation between Body Temperature and Stroke Severity

    PubMed Central

    Hu, Heng; Doll, Danielle N.; Sun, Jiahong; Lewis, Sara E.; Wimsatt, Jeffrey H.; Kessler, Matthew J.; Simpkins, James W.; Ren, Xuefang

    2016-01-01

    Stroke is the second leading cause of death worldwide. The prognostic influence of body temperature on acute stroke in patients has been recently reported; however, hypothermia has confounded experimental results in animal stroke models. This work aimed to investigate how body temperature could prognose stroke severity as well as reveal a possible mitochondrial mechanism in the association of body temperature and stroke severity. Lipopolysaccharide (LPS) compromises mitochondrial oxidative phosphorylation in cerebrovascular endothelial cells (CVECs) and worsens murine experimental stroke. In this study, we report that LPS (0.1 mg/kg) exacerbates stroke infarction and neurological deficits, in the mean time LPS causes temporary hypothermia in the hyperacute stage during 6 hours post-stroke. Lower body temperature is associated with worse infarction and higher neurological deficit score in the LPS-stroke study. However, warming of the LPS-stroke mice compromises animal survival. Furthermore, a high dose of LPS (2 mg/kg) worsens neurological deficits, but causes persistent severe hypothermia that conceals the LPS exacerbation of stroke infarction. Mitochondrial respiratory chain complex I inhibitor, rotenone, replicates the data profile of the LPS-stroke study. Moreover, we have confirmed that rotenone compromises mitochondrial oxidative phosphorylation in CVECs. Lastly, the pooled data analyses of a large sample size (n=353) demonstrate that stroke mice have lower body temperature compared to sham mice within 6 hours post-surgery; the body temperature is significantly correlated with stroke outcomes; linear regression shows that lower body temperature is significantly associated with higher neurological scores and larger infarct volume. We conclude that post-stroke body temperature predicts stroke severity and mitochondrial impairment in CVECs plays a pivotal role in this hypothermic response. These novel findings suggest that body temperature is prognostic for

  7. Mitochondrial Impairment in Cerebrovascular Endothelial Cells is Involved in the Correlation between Body Temperature and Stroke Severity.

    PubMed

    Hu, Heng; Doll, Danielle N; Sun, Jiahong; Lewis, Sara E; Wimsatt, Jeffrey H; Kessler, Matthew J; Simpkins, James W; Ren, Xuefang

    2016-01-01

    Stroke is the second leading cause of death worldwide. The prognostic influence of body temperature on acute stroke in patients has been recently reported; however, hypothermia has confounded experimental results in animal stroke models. This work aimed to investigate how body temperature could prognose stroke severity as well as reveal a possible mitochondrial mechanism in the association of body temperature and stroke severity. Lipopolysaccharide (LPS) compromises mitochondrial oxidative phosphorylation in cerebrovascular endothelial cells (CVECs) and worsens murine experimental stroke. In this study, we report that LPS (0.1 mg/kg) exacerbates stroke infarction and neurological deficits, in the mean time LPS causes temporary hypothermia in the hyperacute stage during 6 hours post-stroke. Lower body temperature is associated with worse infarction and higher neurological deficit score in the LPS-stroke study. However, warming of the LPS-stroke mice compromises animal survival. Furthermore, a high dose of LPS (2 mg/kg) worsens neurological deficits, but causes persistent severe hypothermia that conceals the LPS exacerbation of stroke infarction. Mitochondrial respiratory chain complex I inhibitor, rotenone, replicates the data profile of the LPS-stroke study. Moreover, we have confirmed that rotenone compromises mitochondrial oxidative phosphorylation in CVECs. Lastly, the pooled data analyses of a large sample size (n=353) demonstrate that stroke mice have lower body temperature compared to sham mice within 6 hours post-surgery; the body temperature is significantly correlated with stroke outcomes; linear regression shows that lower body temperature is significantly associated with higher neurological scores and larger infarct volume. We conclude that post-stroke body temperature predicts stroke severity and mitochondrial impairment in CVECs plays a pivotal role in this hypothermic response. These novel findings suggest that body temperature is prognostic for

  8. Recombinant T Cell Receptor Ligand (RTL) Treats Experimental Stroke

    PubMed Central

    Subramanian, Sandhya; Zhang, Bing; Kosaka, Yasuharu; Burrows, Gregory G.; Grafe, Marjorie R.; Vandenbark, Arthur A.; Hurn, Patricia D.; Offner, Halina

    2009-01-01

    Background and Purpose Experimental stroke induces a biphasic effect on the immune response that involves early activation of peripheral leukocytes followed by severe immunodepression and atrophy of spleen and thymus. In tandem, the developing infarct is exacerbated by influx of numerous inflammatory cell types, including T and B lymphocytes. These features of stroke prompted our use of Recombinant T Cell Receptor Ligands (RTL), partial MHC class II molecules covalently bound to myelin peptides. We tested the hypothesis that RTL would improve ischemic outcome in brain without exacerbating defects in peripheral immune system function. Methods Four daily doses of RTL were administered subcutaneously to C57BL/6 mice after middle cerebral artery occlusion (MCAO), and lesion size and cellular composition were assessed in brain, and cell numbers were assessed in spleen and thymus. Results Treatment with RTL551 (I-Ab molecule linked to MOG-35−55 peptide) reduced cortical and total stroke lesion size by ∼50%, inhibited the accumulation of inflammatory cells, particularly macrophages/activated microglial cells and dendritic cells, and mitigated splenic atrophy. Treatment with RTL1000 (HLA-DR2 moiety linked to human MOG-35−55 peptide) similarly reduced the stroke lesion size in HLA-DR2 transgenic mice. In contrast, control RTL with a non-neuroantigen peptide or a mismatched MHC class II moiety had no effect on stroke lesion size. Conclusions These data are the first to demonstrate successful treatment of experimental stroke using a neuroantigen specific immunomodulatory agent administered after ischemia, suggesting therapeutic potential in human stroke. PMID:19443805

  9. Comparative Effectiveness of Prestroke Aspirin on Stroke Severity and Outcome

    PubMed Central

    Park, Jong‐Moo; Kang, Kyusik; Cho, Yong‐Jin; Hong, Keun‐Sik; Lee, Kyung Bok; Park, Tai Hwan; Lee, Soo Joo; Ko, Youngchai; Han, Moon‐Ku; Lee, Jun; Cha, Jae‐Kwan; Kim, Dae‐Hyun; Kim, Dong‐Eog; Kim, Joon‐Tae; Choi, Jay Chol; Yu, Kyung‐Ho; Lee, Byung‐Chul; Lee, Ji Sung; Lee, Juneyoung; Gorelick, Philip B.

    2016-01-01

    Objective The effect of prestroke aspirin use on initial severity, hemorrhagic transformation, and functional outcome of ischemic stroke is uncertain. Methods Using a multicenter stroke registry database, patients with acute ischemic stroke of three subtypes (large artery atherosclerosis [LAA], small vessel occlusion [SVO], or cardioembolism [CE]) were identified. NIH stroke scale (NIHSS) and hemorrhagic transformation at presentation and discharge modified Rankin Scale (mRS) were compared between prestroke aspirin users and nonusers. Results Among the 10,433 patients, 1,914 (18.3%) reported prestroke aspirin use. On crude analysis, initial NIHSS scores of aspirin users were higher than nonusers (mean difference: 0.35; 95% confidence interval [CI]: 0.04–0.66). However, a multivariable analysis with an application of inverse probability of treatment weighting based on a propensity score of prestroke aspirin, having an interaction effect of prestroke aspirin use and stroke subtype in the model, showed less stroke severity for aspirin users in LAA, but not in SVO and CE than for nonusers; mean difference in NIHSS scores in LAA was –0.97 (95% CI: –1.45 to –0.49). With respect to hemorrhagic transformation and mRS, no significant interaction effects were found. Prestroke aspirin use increased the risk of hemorrhagic transformation (adjusted odd ratio: 1.34; 95% CI: 1.05–1.73), but decreased the odds of the higher discharge mRS (0.86; 0.76–0.96). Interpretation Prestroke aspirin use may reduce initial stroke severity in atherothrombotic stroke and can improve functional outcome at discharge despite an increase of hemorrhagic transformation irrespective of stroke subtype. Ann Neurol 2016;79:560–568 PMID:26754410

  10. Effect of experience of severe stroke on subjective valuations of quality of life after stroke

    PubMed Central

    Murphy, R; Sackley, C; Miller, P; Harwood, R

    2001-01-01

    Previous work suggests that the quality of life associated with severe disability after stroke is rated very poorly by members of the public, often as being worse than death. Other evidence suggests that experience of illness alters perceptions of its severity. This was tested for severe stroke. Eleven patients with severely disabling stroke, but able to complete a standard gamble interview, 22 age and sex matched controls, and 20 health professionals participated. A standard gamble interview was carried out to determine the quality of life (utility) associated with three hypothetical scenarios representing mild, moderate, and severe stroke, and current health. A sample was retested for reliability, and comparisons were made with other measures of health status. All three subject groups showed wide variation in the utilities they attached to each of the scenarios. The control subjects' valuations were lower than those of either patients or staff members, especially for moderate stroke (median 0.30, 0.73, and 0.68 respectively). There were weak to moderate correlations between utilities and other measures of health status including the Barthel index (r=0.51) and Rivermead mobility score (r=0.24). Test retest-reliability was modest (reliability coefficient 0.75), but indicators of the internal validity of the results were good. In conclusion, it cannot be assumed that general population valuations are valid for patient groups. In clinical practice it is unsafe to make any assumption about subjective quality of life after stroke, due to the wide range of valuations given, although many people rate severe and moderate stroke at least as bad as death.

 PMID:11309467

  11. Interactions between Age, Sex, and Hormones in Experimental Ischemic Stroke

    PubMed Central

    Liu, Fudong; McCullough, Louise D.

    2012-01-01

    Age, sex, and gonadal hormones have profound effects on ischemic stroke outcomes, although how these factors impact basic stroke pathophysiology remains unclear. There is a plethora of inconsistent data reported throughout the literature, primarily due to differences in the species examined, the timing and methods used to evaluate injury, the models used, and confusion regarding differences in stroke incidence as seen in clinical populations versus effects on acute neuroprotection or neurorepair in experimental stroke models. Sex and gonadal hormone exposure have considerable independent impact on stroke outcome, but these factors also interact with each other, and the contribution of each differs throughout the lifespan. The contribution of sex and hormones to experimental stroke will be the focus of this review. Recent advances and our current understanding of age, sex, and hormone interactions in ischemic stroke with a focus on inflammation will be discussed. PMID:23068990

  12. Neuroanatomical correlates of severe cardiac arrhythmias in acute ischemic stroke.

    PubMed

    Seifert, Frank; Kallmünzer, Bernd; Gutjahr, Isabell; Breuer, Lorenz; Winder, Klemens; Kaschka, Iris; Kloska, Stephan; Doerfler, Arnd; Hilz, Max-Josef; Schwab, Stefan; Köhrmann, Martin

    2015-05-01

    Neurocardiological interactions can cause severe cardiac arrhythmias in patients with acute ischemic stroke. The relationship between the lesion location in the brain and the occurrence of cardiac arrhythmias is still discussed controversially. The aim of the present study was to correlate the lesion location with the occurrence of cardiac arrhythmias in patients with acute ischemic stroke. Cardiac arrhythmias were systematically assessed in patients with acute ischemic stroke during the first 72 h after admission to a monitored stroke unit. Voxel-based lesion-symptom mapping (VLSM) was used to correlate the lesion location with the occurrence of clinically relevant severe arrhythmias. Overall 150 patients, 56 with right-hemispheric and 94 patients with a left-hemispheric lesion, were eligible to be included in the VLSM study. Severe cardiac arrhythmias were present in 49 of these 150 patients (32.7%). We found a significant association (FDR correction, q < 0.05) between lesions in the right insular, right frontal and right parietal cortex as well as the right amygdala, basal ganglia and thalamus and the occurrence of cardiac arrhythmias. Because left- and right-hemispheric lesions were analyzed separately, the significant findings rely on the 56 patients with right-hemispheric lesions. The data indicate that these areas are involved in central autonomic processing and that right-hemispheric lesions located to these areas are associated with an elevated risk for severe cardiac arrhythmias.

  13. Decoding upper limb residual muscle activity in severe chronic stroke

    PubMed Central

    Ramos-Murguialday, Ander; García-Cossio, Eliana; Walter, Armin; Cho, Woosang; Broetz, Doris; Bogdan, Martin; Cohen, Leonardo G; Birbaumer, Niels

    2015-01-01

    Objective Stroke is a leading cause of long-term motor disability. Stroke patients with severe hand weakness do not profit from rehabilitative treatments. Recently, brain-controlled robotics and sequential functional electrical stimulation allowed some improvement. However, for such therapies to succeed, it is required to decode patients' intentions for different arm movements. Here, we evaluated whether residual muscle activity could be used to predict movements from paralyzed joints in severely impaired chronic stroke patients. Methods Muscle activity was recorded with surface-electromyography (EMG) in 41 patients, with severe hand weakness (Fugl-Meyer Assessment [FMA] hand subscores of 2.93 ± 2.7), in order to decode their intention to perform six different motions of the affected arm, required for voluntary muscle activity and to control neuroprostheses. Decoding of paretic and nonparetic muscle activity was performed using a feed-forward neural network classifier. The contribution of each muscle to the intended movement was determined. Results Decoding of up to six arm movements was accurate (>65%) in more than 97% of nonparetic and 46% of paretic muscles. Interpretation These results demonstrate that some level of neuronal innervation to the paretic muscle remains preserved and can be used to implement neurorehabilitative treatments in 46% of patients with severe paralysis and extensive cortical and/or subcortical lesions. Such decoding may allow these patients for the first time after stroke to control different motions of arm prostheses through muscle-triggered rehabilitative treatments. PMID:25642429

  14. Severe amnesia following a unilateral temporal lobe stroke.

    PubMed

    Grewal, Raji P

    2003-01-01

    A 60 year old right-handed man developed severe amnesia following a left medial temporal stroke as documented by cerebral MRI, MRA and SPECT scans. Neuropsychological evaluation 13 weeks after the stroke showed a profound retrograde amnesia characterised by memory loss for public facts and events over the previous four decades. In addition, autobiographical memory showed selective loss of personal episodic memory with relative preservation of personal semantic memory. The development of this degree of amnesia with these features following a unilateral temporal lobe lesion is unusual. The possible neuroanatomical mechanisms underlying the amnesia and how they relate to current theories of memory loss are discussed. PMID:12464535

  15. Biomaterial Applications in Cell-Based Therapy in Experimental Stroke

    PubMed Central

    Boisserand, Ligia S. B.; Kodama, Tomonobu; Papassin, Jérémie; Auzely, Rachel; Moisan, Anaïck; Rome, Claire; Detante, Olivier

    2016-01-01

    Stroke is an important health issue corresponding to the second cause of mortality and first cause of severe disability with no effective treatments after the first hours of onset. Regenerative approaches such as cell therapy provide an increase in endogenous brain structural plasticity but they are not enough to promote a complete recovery. Tissue engineering has recently aroused a major interesting development of biomaterials for use into the central nervous system. Many biomaterials have been engineered based on natural compounds, synthetic compounds, or a mix of both with the aim of providing polymers with specific properties. The mechanical properties of biomaterials can be exquisitely regulated forming polymers with different stiffness, modifiable physical state that polymerizes in situ, or small particles encapsulating cells or growth factors. The choice of biomaterial compounds should be adapted for the different applications, structure target, and delay of administration. Biocompatibilities with embedded cells and with the host tissue and biodegradation rate must be considerate. In this paper, we review the different applications of biomaterials combined with cell therapy in ischemic stroke and we explore specific features such as choice of biomaterial compounds and physical and mechanical properties concerning the recent studies in experimental stroke. PMID:27274738

  16. Methodological standards for experimental research on stroke using scalp acupuncture.

    PubMed

    Zheng, Guo-qing

    2009-01-01

    Scalp acupuncture (SA) is a modality based on different physiologic functions of different brain areas, using needles to stimulate different scalp zones so as to excite the reflex-related nervous tissue. The findings of several studies showed that the clinical effect of SA on stroke was significant, but the exact mechanism is still unclear. In this research, some new ways of thinking and new methodological standards on stroke experiment using SA are put forward. They are as follows: A, establishment of standard animal model of stroke; B, simulation of head acupoint line on animal model following traditional Chinese medicine localization; C, acupuncture manipulation and quantity of stimulus for SA in animal model; D, optimal curative opportunity and instant effect of SA therapy on stroke; E, mechanism study of SA on stroke. This research may provide methodological reference for future mechanism study on stroke experiment using SA. PMID:19711771

  17. Of mice and men: modelling post-stroke depression experimentally

    PubMed Central

    Kronenberg, G; Gertz, K; Heinz, A; Endres, M

    2014-01-01

    At least one-third of stroke survivors suffer from depression. The development of comorbid depression after stroke is clinically highly significant because post-stroke depression is associated with increased mortality, slows recovery and leads to worse functional outcomes. Here, we review the evidence that post-stroke depression can be effectively modelled in experimental rodents via a variety of approaches. This opens an exciting new window onto the neurobiology of depression and permits probing potential underlying mechanisms such as disturbed cellular plasticity, neuroendocrine dysregulation, neuroinflammation, and neurodegeneration in a novel context. From the point of view of translational stroke research, extending the scope of experimental investigations beyond the study of short-term end points and, in particular, acute lesion size, may help improve the relevance of preclinical results to human disease. Furthermore, accumulating evidence from both clinical and experimental studies offers the tantalizing prospect of 5-hydroxytryptaminergic antidepressants as the first pharmacological therapy for stroke that would be available during the subacute and chronic phases of recovery. Interdisciplinary neuropsychiatric research will be called on to dissect the mechanisms underpinning the beneficial effects of antidepressants on stroke recovery. Linked Articles This article is part of a themed section on Animal Models in Psychiatry Research. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-20 PMID:24838087

  18. Ultrasonic Vocalization Changes and FOXP2 expression after Experimental Stroke

    PubMed Central

    Doran, Sarah J; Trammel, Cassandra; Benashaski, Sharon E; Venna, Venugopal Reddy; McCullough, Louise D

    2015-01-01

    Speech impairments affect one in four stroke survivors. However, animal models of post-ischemic vocalization deficits are limited. Male mice vocalize at ultrasonic frequencies when exposed to an estrous female mouse. In this study we assessed vocalization patterns and quantity in male mice after cerebral ischemia. FOXP2, a gene associated with verbal dyspraxia in humans, with known roles in neurogenesis and synaptic plasticity, was also examined after injury. Using a transient middle cerebral artery occlusion (MCAO) model, we assessed correlates of vocal impairment at several time-points after stroke. Further, to identify possible lateralization of vocalization deficits induced by left and right hemispheric strokes were compared. Significant differences in vocalization quantity were observed between stroke and sham animals that persisted for a month after injury. Injury to the left hemisphere reduced early vocalizations more profoundly than those to the right hemisphere. Nuclear expression of Foxp2 was elevated early after stroke (at 6 hours), but significantly decreased 24 hours after injury in both the nucleus and the cytoplasm. Neuronal Foxp2 expression increased in stroke mice compared to sham animals 4 weeks after injury. This study demonstrates that quantifiable deficits in ultrasonic vocalizations (USVs) are seen after stroke. USV may be a useful tool to assess chronic behavioral recovery in murine models of stroke. PMID:25644653

  19. Ultrasonic vocalization changes and FOXP2 expression after experimental stroke.

    PubMed

    Doran, Sarah J; Trammel, Cassandra; Benashaski, Sharon E; Venna, Venugopal Reddy; McCullough, Louise D

    2015-04-15

    Speech impairments affect one in four stroke survivors. However, animal models of post-ischemic vocalization deficits are limited. Male mice vocalize at ultrasonic frequencies when exposed to an estrous female mouse. In this study we assessed vocalization patterns and quantity in male mice after cerebral ischemia. FOXP2, a gene associated with verbal dyspraxia in humans, with known roles in neurogenesis and synaptic plasticity, was also examined after injury. Using a transient middle cerebral artery occlusion (MCAO) model, we assessed correlates of vocal impairment at several time-points after stroke. Further, to identify possible lateralization of vocalization deficits induced by left and right hemispheric strokes were compared. Significant differences in vocalization quantity were observed between stroke and sham animals that persisted for a month after injury. Injury to the left hemisphere reduced early vocalizations more profoundly than those to the right hemisphere. Nuclear expression of Foxp2 was elevated early after stroke (at 6h), but significantly decreased 24h after injury in both the nucleus and the cytoplasm. Neuronal Foxp2 expression increased in stroke mice compared to sham animals 4 weeks after injury. This study demonstrates that quantifiable deficits in ultrasonic vocalizations (USVs) are seen after stroke. USV may be a useful tool to assess chronic behavioral recovery in murine models of stroke.

  20. Methylene blue treatment in experimental ischemic stroke: a mini review

    PubMed Central

    Jiang, Zhao; Duong, Timothy Q

    2016-01-01

    Stroke is a leading cause of death and long-term disability. Methylene blue, a drug grandfathered by the Food and Drug Administration with a long history of safe usage in humans for treating methemoglobinemia and cyanide poisoning, has recently been shown to be neuroprotective in neurodegenerative diseases and brain injuries. The goal of this paper is to review studies on methylene blue in experimental stroke models. PMID:27042692

  1. Neurological Symptom Severity after a Recent Non-cardioembolic Stroke and Recurrent Vascular Risk

    PubMed Central

    Park, Jong-Ho; Ovbiagele, Bruce

    2015-01-01

    Background There is a well-established relation of symptom severity with functional status and mortality after an index stroke. However, little is known about the impact of symptom severity of a recent index stroke on risk of recurrent vascular events. Methods We reviewed the dataset of a multicenter trial involving 3680 recent non-cardioembolic stroke patients aged ≥35 years and followed for 2 years. Independent associations of stroke severity (as measured by National Institutes of Health Stroke Scale [NIHSS] score) with recurrent stroke (primary outcome) and stroke/coronary heart disease (CHD)/vascular death (secondary outcome) were analyzed. NIHSS score was analyzed as a dichotomous (<4 vs. ≥4) and a continuous variable. Results Among study subjects, 550 (15%) had NIHSS scores ≥4 (overall scores ranged from 0 to 18, median score was 1 [25th to 75th percentile 0 to 2]). NIHSS was measured at a median 35 days after the index stroke. After adjusting for multiple covariates, NIHSS ≥4 was independently linked to higher risk of recurrent stroke (HR 1.37, 95% CI: 1.01–1.84) and risk of stroke/CHD/vascular death (HR 1.32, 95% CI: 1.07–1.64). Analysis of NIHSS score as a continuous variable also showed a higher risk of recurrent stroke (HR 1.06, 95% CI: 1.00–1.12) and stroke/CHD/vascular death (HR 1.05, 95% CI: 1.01–1.09) with increasing index stroke symptom severity. Conclusions Greater residual symptom severity after a recent stroke is associated with higher risk of recurrent vascular events. Future studies are needed to confirm this relationship and to clarify its underlying mechanisms. PMID:25817617

  2. Cortisol levels and the severity and outcomes of acute stroke: a systematic review.

    PubMed

    Barugh, Amanda Jayne; Gray, Paul; Shenkin, Susan Deborah; MacLullich, Alasdair Maurice Joseph; Mead, Gillian Elizabeth

    2014-03-01

    Studies in non-stroke patients have shown an association between dysregulation of the hypothalamic-pituitary-adrenal axis and morbidity and mortality. We conducted a systematic review to evaluate cortisol levels in acute stroke and their associations with outcome. We searched MEDLINE and EMBASE for articles up to April 2013 and PsychINFO for articles up to July 2013, using the keywords "cortisol" and "stroke" and associated terms or synonyms. We included studies published in peer-reviewed journals that recruited 10 or more participants and measured cortisol at least once in the first year following stroke. Data were extracted regarding cortisol levels, including changes over time and their relationship to stroke severity, and outcome. Of 11,240 abstracts, 101 full texts were obtained and 48 fulfilled our inclusion criteria. Cortisol levels were high in the first week after stroke in the majority of studies (26 studies, n = 1,340). Higher cortisol was associated with dependency (8/11 studies, n = 822), delirium (5/6 studies, n = 269) depression (3/5 studies n = 117) and mortality (8/10 studies, n = 856). Five studies adjusted for stroke severity; one found an association between higher cortisol and dependency, and three found an association between higher cortisol and mortality. Cortisol levels are high for at least 7 days after stroke. Elevated cortisol after stroke is associated with dependency, morbidity, and mortality; however, there is insufficient evidence to conclude that these relationships are independent of stroke severity.

  3. The Number of Stenotic Intracranial Arteries Is Independently Associated with Ischemic Stroke Severity

    PubMed Central

    Yang, Chunhua; Wang, Wenming; Li, Xianglin; Zhang, Shuping; Li, Xuri; Tian, Geng; Bergquist, Jonas; Wang, Bin; Mi, Jia

    2016-01-01

    Background The severity of ischemic stroke symptoms varies among patients and is a critical determinant of patient outcome. To date, the association between the number of stenotic intracranial arteries and stroke severity remains unclear. Aims We aimed to investigate the association between the number of stenotic major intracranial arteries (NSMIA) and ischemic stroke severity, as well as the degree of stenosis and common stroke risk factors. Methods We performed a retrospective analysis of patients with digital subtraction angiography (DSA)-confirmed ischemic stroke. Clinical stroke severity was measured using the National Institutes of Health Stroke Scale (NIHSS). The number of stenotic vessels was counted from the internal carotid arteries and vertebral arteries, bilaterally. Results Eighty three patients were recruited from a single center and included in the study. NSMIA was significantly correlated with stroke severity (Pearson Correlation Coefficient = 0.485, P < 0.001), but not with the degree of stenosis (Pearson Correlation Coefficient = 0.01, P = 0.90). Multivariate regression analysis revealed that NSMIA was significantly associated with the NIHSS score after adjusting for stroke risk factors. The adjusted odds ratio (per lateral) was 2.092 (95% CI, 0.865 to 3.308, P = 0.001). The degree of stenosis was also significantly associated with the NIHSS score after adjusting for common risk factors. The odds ratio (per 10%) was 0.712 (95% CI, 0.202 to 1.223, P = 0.007). Conclusions The number of stenotic intracranial major arteries is associated with the severity of ischemic stroke independent of the degree of stenosis and other stroke risk factors. To the best of our knowledge, this has not been previosuly studied in great detail using DSA. Our data highlight the importance of examining all major arteries in stroke patients. PMID:27649086

  4. Stress as necessary component of realistic recovery in animal models of experimental stroke

    PubMed Central

    Walker, Frederick R; Jones, Kimberley A; Patience, Madeleine J; Zhao, Zidan; Nilsson, Michael

    2014-01-01

    Over the last decade there has been a considerable effort directed toward reformulating the standard approach taken to preclinically model stroke and stroke recovery. The principal objective of this undertaking has been to improve the success with which preclinical findings can be translated. Although several advancements have already been introduced, one potentially critical feature that appears to have been overlooked is psychological stress. Stroke is well recognized to produce high levels of stress in patients, and ongoing exposure to stress is recognized to deleteriously interfere with recovery. The presence of high levels of stress (distress) in stroke patients is also relevant because nearly all clinically deployed neurorestorative interventions occur against this background. Somewhat perplexingly, however, we could find no preclinical stroke studies concerned with investigating the efficacy of putative neurorestorative compounds that did so in the presence of stress. The following article will make the case that failure to recognize or compensate for the effects of ongoing stress in standard preclinical experimental models of recovery is likely to result in overestimation of the effectiveness of pharmacological or behavioral neurorestorative interventions. PMID:24326386

  5. Effect of prior medical treatments on ischemic stroke severity and outcome

    PubMed Central

    Sacco, Simona; Toni, Danilo; Bignamini, Angelo A.; Zaninelli, Augusto; Gensini, Gian Franco; Carolei, Antonio

    Summary Antiplatelets, antihypertensives, and statins might reduce the severity of the event or improve outcome in patients who, despite prior medical treatment, have a stroke. We evaluated, in patients who had an ischemic stroke, the effect, on stroke severity and outcome, of prior treatment with antiplatelets, antihypertensives, and statins, used either alone or in a three-drug combination. Stroke in Italy and Related Impact on Outcome (SIRIO) was a prospective, nationwide, multicenter, hospital-based, observational study that included patients aged ≥18 years with acute ischemic stroke. We studied 2,529 acute ischemic stroke patients from the SIRIO population: 887 were antiplatelet users, 1,497 antihypertensive users, 231 statin users, and 138 three-drug combination users prior to the index event. The adjusted logistic regression analysis showed an association between prior treatment with statins and good functional outcome at discharge, while prior treatment with antiplatelets, antihypertensives or the three-drug combination did not influence severity or outcome. The absolute probability of a good functional outcome was 46.3% (95% CI: 40.3%–53.2%) in statin users and 36.7% (95% CI: 34.7%–38.7%) in non-users of statins; the absolute risk difference was 9.6% (95% CI: 2.9%–16.4%; p=0.004). Prior treatment with antiplatelets, antihypertensives, or the three-drug combination did not influence stroke severity or outcome, while prior treatment with statins did not influence stroke severity but was associated with a better functional outcome. PMID:22152434

  6. Stroke

    MedlinePlus

    ... emergency. Strokes happen when blood flow to your brain stops. Within minutes, brain cells begin to die. There are two kinds ... blocks or plugs a blood vessel in the brain. The other kind, called hemorrhagic stroke, is caused ...

  7. Genetically-Defined Deficiency of Mannose-Binding Lectin Is Associated with Protection after Experimental Stroke in Mice and Outcome in Human Stroke

    PubMed Central

    Cervera, Alvaro; Planas, Anna M.; Justicia, Carles; Urra, Xabier; Jensenius, Jens C.; Torres, Ferran; Lozano, Francisco; Chamorro, Angel

    2010-01-01

    Background The complement system is a major effector of innate immunity that has been involved in stroke brain damage. Complement activation occurs through the classical, alternative and lectin pathways. The latter is initiated by mannose-binding lectin (MBL) and MBL-associated serine proteases (MASPs). Here we investigated whether the lectin pathway contributes to stroke outcome in mice and humans. Methodology/Principal Findings Focal cerebral ischemia/reperfusion in MBL-null mice induced smaller infarctions, better functional outcome, and diminished C3 deposition and neutrophil infiltration than in wild-type mice. Accordingly, reconstitution of MBL-null mice with recombinant human MBL (rhMBL) enhanced brain damage. In order to investigate the clinical relevance of these experimental observations, a study of MBL2 and MASP-2 gene polymorphism rendering the lectin pathway dysfunctional was performed in 135 stroke patients. In logistic regression adjusted for age, gender and initial stroke severity, unfavourable outcome at 3 months was associated with MBL-sufficient genotype (OR 10.85, p = 0.008) and circulating MBL levels (OR 1.29, p = 0.04). Individuals carrying MBL-low genotypes (17.8%) had lower C3, C4, and CRP levels, and the proinflammatory cytokine profile was attenuated versus MBL-sufficient genotypes. Conclusions/Significance In conclusion, genetically defined MBL-deficiency is associated with a better outcome after acute stroke in mice and humans. PMID:20140243

  8. Age-related changes in brain support cells: Implications for stroke severity.

    PubMed

    Sohrabji, Farida; Bake, Shameena; Lewis, Danielle K

    2013-10-01

    Stroke is one of the leading causes of adult disability and the fourth leading cause of mortality in the US. Stroke disproportionately occurs among the elderly, where the disease is more likely to be fatal or lead to long-term supportive care. Animal models, where the ischemic insult can be controlled more precisely, also confirm that aged animals sustain more severe strokes as compared to young animals. Furthermore, the neuroprotection usually seen in younger females when compared to young males is not observed in older females. The preclinical literature thus provides a valuable resource for understanding why the aging brain is more susceptible to severe infarction. In this review, we discuss the hypothesis that stroke severity in the aging brain may be associated with reduced functional capacity of critical support cells. Specifically, we focus on astrocytes, that are critical for detoxification of the brain microenvironment and endothelial cells, which play a crucial role in maintaining the blood brain barrier. In view of the sex difference in stroke severity, this review also discusses studies of middle-aged acyclic females as well as the effects of the estrogen on astrocytes and endothelial cells.

  9. Functional recovery in aging mice after experimental stroke.

    PubMed

    Manwani, Bharti; Liu, Fudong; Xu, Yan; Persky, Rebecca; Li, Jun; McCullough, Louise D

    2011-11-01

    Aging is a non-modifiable risk factor for stroke. Since not all strokes can be prevented, a major emerging area of research is the development of effective strategies to enhance functional recovery after stroke. However, in the vast majority of pre-clinical stroke studies, the behavioral tests used to assess functional recovery have only been validated for use in young animals, or are designed for rats. Mice are increasingly utilized in stroke models but well validated behavioral tests designed for rats are not necessarily reproducible in mice. We examined a battery of behavioral tests to evaluate functional recovery in an aging murine model of stroke. We found that the vertical pole, hanging wire and open field can accurately assess acute behavioral impairments after stroke in both young and aging male mice, but animals recover rapidly on these tasks. The corner test can accurately and repeatedly differentiate stroke from sham animals up to 30 days post stroke and can be performed reliably in aging mice. Aging male mice had significantly worse behavioral impairment compared to young male mice in the first two weeks after stroke but eventually recovered to the same degree as young mice. In contrast, chronic infarct size, as measured by ipsilateral cerebral atrophy, was significantly lower in aging male mice compared to young male mice. Reactive gliosis, formation of glial scar, and an enhanced innate immune response was seen in the aging brain and may contribute to the delayed behavioral recovery seen in the aging animals.

  10. Experimental reproduction of severe bluetongue in sheep.

    PubMed

    MacLachlan, N J; Crafford, J E; Vernau, W; Gardner, I A; Goddard, A; Guthrie, A J; Venter, E H

    2008-05-01

    Sheep inoculated with a virulent South African strain of bluetongue (BT) virus serotype 4 developed severe clinical signs and lesions characteristic of fulminant BT, including coronitis, hemorrhage and ulceration of the mucosal lining of the oral cavity and forestomaches, hemorrhage in the wall of the pulmonary artery, and focally extensive necrosis of skeletal muscle, especially of the neck. At necropsy, up to 14 days after infection, the infected sheep exhibited striking pulmonary edema, edema of the subcutaneous tissues and fascial planes of the head and neck, and pleural and pericardial effusion of varying severity. A reliable model for experimental reproduction of fulminant BT in sheep will facilitate future studies to better characterize the pathogenesis of this disease, particularly as it regards the mechanisms responsible for the increased vascular permeability that characterizes BT and related orbiviral diseases such as African horse sickness. PMID:18487487

  11. The Effects of Interspersed Maintenance Tasks on Academic Performance in a Severe Childhood Stroke Victim.

    ERIC Educational Resources Information Center

    Koegel, Lynn Kern; Koegel, Robert L.

    1986-01-01

    The study examined effects of task-sequencing variables on the academic performance of an 8-year-old severe stroke victim. Previously acquired (maintenance) task trials were systematically interspersed among new (acquisition) task trials. Results showed improvements in both academic responding and subjective ratings of motivation in spelling,…

  12. Arterial Hypertension Aggravates Innate Immune Responses after Experimental Stroke

    PubMed Central

    Möller, Karoline; Pösel, Claudia; Kranz, Alexander; Schulz, Isabell; Scheibe, Johanna; Didwischus, Nadine; Boltze, Johannes; Weise, Gesa; Wagner, Daniel-Christoph

    2015-01-01

    Arterial hypertension is not only the leading risk factor for stroke, but also attributes to impaired recovery and poor outcome. The latter could be explained by hypertensive vascular remodeling that aggravates perfusion deficits and blood–brain barrier disruption. However, besides vascular changes, one could hypothesize that activation of the immune system due to pre-existing hypertension may negatively influence post-stroke inflammation and thus stroke outcome. To test this hypothesis, male adult spontaneously hypertensive rats (SHRs) and normotensive Wistar Kyoto rats (WKYs) were subjected to photothrombotic stroke. One and 3 days after stroke, infarct volume and functional deficits were evaluated by magnetic resonance imaging and behavioral tests. Expression levels of adhesion molecules and chemokines along with the post-stroke inflammatory response were analyzed by flow cytometry, quantitative real-time PCR and immunohistochemistry in rat brains 4 days after stroke. Although comparable at day 1, lesion volumes were significantly larger in SHR at day 3. The infarct volume showed a strong correlation with the amount of CD45 highly positive leukocytes present in the ischemic hemispheres. Functional deficits were comparable between SHR and WKY. Brain endothelial expression of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and P-selectin (CD62P) was neither increased by hypertension nor by stroke. However, in SHR, brain infiltrating myeloid leukocytes showed significantly higher surface expression of ICAM-1 which may augment leukocyte transmigration by leukocyte–leukocyte interactions. The expression of chemokines that primarily attract monocytes and granulocytes was significantly increased by stroke and, furthermore, by hypertension. Accordingly, ischemic hemispheres of SHR contain considerably higher numbers of monocytes, macrophages and granulocytes. Exacerbated brain inflammation in SHR may finally be responsible for

  13. Two cases of acute atraumatic compartment syndrome complicated with severe heat stroke.

    PubMed

    Ikegami, Yukihiro; Hasegawa, Arifumi; Tsukada, Yasuhiko; Abe, Yoshinobu; Shimada, Jiro; Tase, Choichiro

    2010-12-01

    Acute compartment syndrome is a life-threatening complication in trauma patients. Not only regional neuromuscular disability, but also systemic organ disorders can result from prolonged tissue ischemia. In this report, we describe 2 cases of acute atraumatic compartment syndrome complicated with severe heat stroke. In both cases, emergency fasciotomy was rapidly performed after recognition of the syndrome, but serious regional neuromuscular disabilities remained. Microvascular endothelial injury is an important mechanism of acute atraumatic compartment syndrome. Thrombi diffusely formed in the compartmental space hinder establishment of reperfusion even after fasciotomy. Furthermore, disruption of fibrinolysis due to heat stroke could enhance this damage.

  14. Use of telemedicine to manage severe ischaemic strokes in a rural area with an elderly population.

    PubMed

    Richard, Sébastien; Lavandier, K; Zioueche, Y; Pelletier, S; Vezain, A; Ducrocq, X

    2014-05-01

    The rural district of the Meuse (East France) has a high number of elderly patients for whom prognosis of ischaemic strokes is poor with high-haemorrhagic transformation risk of intravenous tissue plasminogen activator (rt-PA). This disadvantage is made worse by the distances a patient has to travel to the nearest stroke unit. We set out to assess the effectiveness of a telestroke system implemented in this area. Between October 2010 and February 2012, data from each "tele-expertised" patient were collected. 53 patients were examined. Diagnosis of ischaemic stroke was confirmed in 43 cases (81 %), and intravenous rt-PA treatment performed in 21 cases (40 %). In the treated patient group, median age was 73 years, with 29 % of octogenarians. Baseline National Institutes of Health Stroke Scale (NIHSS) was 16, with 29 % ≥ 20. The median onset to needle time was 169 min, and the median door to needle time was 69 min. Intracranial haemorrhage occurred in 3 cases (14 %), and was symptomatic in two (10 %). At 3 months, median NIHSS was 6, 6 patients (29 %) presented a favourable outcome (modified Rankin scale ≤ 1) and 3 (14 %) had died. In rural areas, for elderly patients with severe ischaemic strokes, telemedicine appears to be a way of improving accessibility and benefits of rt-PA treatment. PMID:24277200

  15. Experimental animal models and inflammatory cellular changes in cerebral ischemic and hemorrhagic stroke

    PubMed Central

    Yan, Tao; Chopp, Michael; Chen, Jieli

    2015-01-01

    Stroke, including cerebral ischemia, intracerebral hemorrhage, and subarachnoid hemorrhage, is the leading cause of long-term disability and death worldwide. Animal models have greatly contributed to our understanding of the risk factors and the pathophysiology of stroke, as well as the development of therapeutic strategies for its treatment. Further development and investigation of experimental models, however, are needed to elucidate the pathogenesis of stroke and to enhance and expand novel therapeutic targets. In this article, we provide an overview of the characteristics of commonly-used animal models of stroke and focus on the inflammatory responses to cerebral stroke, which may provide insights into a framework for developing effective therapies for stroke in humans. PMID:26625873

  16. [Stroke].

    PubMed

    Luft, A R; Weller, M

    2009-11-01

    Ischemic stroke is a very frequent neurological disorder. It's incidence is increasing as western societies are aging. Effective therapies that reduce mortality and increase the chances of living symptom-free or, at least, in independence are available. Intravenous or intraarterial thrombolysis is an effective treatment with a number needed to treat of 6 if given within 4.5 hours after symptom onset. The safe use of thrombolysis requires an effective and repeatedly trained workflow established within a team of a neurologist and specialized nursing staff in an optimized environment (admission, imaging facility, laboratory, stroke unit). After peracute treatment, the patient should be transferred to a stroke unit. This unit is a spatially defined intermediate care unit with specifically trained personnel (physicians, nurses, therapists). Treating the patient in a stroke unit is as effective in improving outcome as thrombolysis and also reduces the length of hospital stay. In contrast to thrombolysis, which can be provided, on average, to only 5% of stroke patients, stroke unit care is applicable to most. The organization of medical care in most European countries and in Switzerland separate the acute phase from subacute rehabilitation and chronic stroke treatment. This can be highly confusing for the patient who, during the course of the disease, meets different physicians, nurses and therapists with often diverging opinions about prognosis and therapies. Consistent treatment approaches and patient/caregiver information is necessary and can only be implemented by providing a homogeneous pathway for continuous stroke care. PMID:20029781

  17. The crossed leg sign indicates a favorable outcome after severe stroke

    PubMed Central

    Rémi, J.; Pfefferkorn, T.; Owens, R.L.; Schankin, C.; Dehning, S.; Birnbaum, T.; Bender, A.; Klein, M.; Adamec, J.; Pfister, H.-W.; Straube, A.

    2011-01-01

    Objective: We investigated whether crossed legs are a prognostic marker in patients with severe stroke. Methods: In this controlled prospective observational study, we observed patients with severe stroke who crossed their legs during their hospital stay and matched them with randomly selected severe stroke patients who did not cross their legs. The patients were evaluated upon admission, on the day of leg crossing, upon discharge, and at 1 year after discharge. The Glasgow Coma Scale, the NIH Stroke Scale (NIHSS), the modified Rankin Scale (mRS), and the Barthel Index (BI) were obtained. Results: Patients who crossed their legs (n = 34) and matched controls (n = 34) did not differ in any scale upon admission. At the time of discharge, the GCS did not differ, but the NIHSS was better in crossed legs patients (6.5 vs 10.6; p = 0.0026), as was the mRS (3.4 vs 5.1, p < 0.001), and the BI (34.0 vs 21.1; p = 0.0073). At 1-year follow-up, mRS (2.9 vs 5.1, p < 0.001) and the BI (71.3 vs 49.2; p = 0.045) were also better in the crossed leg group. The mortality between the groups differed grossly; only 1 patient died in the crossing group compared to 18 in the noncrossing group (p < 0.001). Conclusion: Leg crossing is an easily obtained clinical sign and is independent of additional technical examinations. Leg crossing within the first 15 days after severe stroke indicates a favorable outcome which includes less neurologic deficits, better independence in daily life, and lower rates of death. PMID:21987641

  18. Prevention of experimental stroke by hypercapnic-hypoxic preconditioning.

    PubMed

    Yakushev, N N; Bespalov, A G; Kulikov, V P

    2008-09-01

    The effectiveness of hypercapnic hypoxic training in the prevention of acute disturbances in cerebral circulation was studied under experimental conditions. Hypercapnic hypoxic training was followed by a significant decrease in the severity of neurological deficit and locomotor and coordination disorders after cerebral ischemic injury. PMID:19240841

  19. Feasibility of a bimanual, lever-driven wheelchair for people with severe arm impairment after stroke.

    PubMed

    Smith, Brendan W; Zondervan, Daniel K; Lord, Thomas J; Chan, Vicky; Reinkensmeyer, David J

    2014-01-01

    Individuals with severe arm impairment after stroke are thought to be unable to use a manual wheelchair in the conventional bimanual fashion, because they cannot grip and push the pushrim with their impaired hand. Instead, they are often taught to propel a wheelchair with their good arm and leg, a compensatory strategy that encourages disuse and may cause asymmetric tone. Here, we show that four stroke survivors (9, 27 50 and 16 months post stroke) with severe arm impairment (upper extremity Fugl Meyer scores of 21, 17, 16 and 15 of 66 respectively) were able to propel themselves overground during ten, 3.3 meter movement trials, using a specially designed lever-driven wheelchair adapted with a splint and elastic bands. Their average speed on the tenth trial was about 0.1 m/sec. These results suggest that individuals with stroke could use bimanual wheelchair propulsion for mobility, both avoiding the problems associated with good-arm/good-leg propulsion and increasing the number of daily arm movements they achieve, which may improve arm movement recovery.

  20. Effect of anticoagulation on cardioembolic stroke severity, outcomes and response to intravenous thrombolysis.

    PubMed

    Illán-Gala, Ignacio; Martínez-Sánchez, Patricia; Fuentes, Blanca; Llamas-Osorio, Yudy; Díaz de Terán, Javier; Báez, Melissa; Ruiz-Ares, Gerardo; Sanz-Cuesta, Borja Enrique; Lara-Lara, Manuel; Díez-Tejedor, Exuperio

    2016-07-01

    Our objective was to evaluate the effect of anticoagulation on cardioembolic stroke (CS) severity, outcomes, and response to intravenous thrombolysis (IVT). Observational study of CS patients admitted to a Stroke Center (2010-2013). The sample was classified into three groups based on pre-stroke oral anticoagulants (OAC) treatment (all acenocumarol) and the international normalized ratio (INR) on admission: (1) non-anticoagulated or anticoagulated patients with INR <1.5, (2) anticoagulated with INR 1.5-1.9 and (3) anticoagulated with INR ≥2. We compared demographic data, vascular risk factors, symptomatic intracranial hemorrhage, severity on admission (NIHSS) and 3 month outcomes (mRS). Overall 475 patients were included, 47.2 % male, mean age 75.5 (SD 10.7) years old, 31.8 % were on OAC. 76 % belonged to the INR <1.5 group, 13.3 % to the INR 1.5-1.9 and 10.5 % to the INR >2. 35 %of patients received IVT. Multivariate analyses showed that an INR ≥2 on admission was a factor associated with a higher probability of mild stroke (NIHSS <10) (OR 2.026, 95 % CI 1.006-4.082). Previous OAC in general (OR 2.109, 95 % CI 1.173-3.789) as well as INR 1.5-1.9 (OR 3.676, 95 % CI 1.510-8.946) were associated with favorable outcomes (mRS ≤2). OAC was not related to stroke outcomes in the subgroup of IVT patients. Therapeutic OAC levels are associated with lesser CS severity, and prior OAC treatment with favorable outcomes. In this study, OAC are not related with response to IVT. PMID:26860861

  1. The effects of interspersed maintenance tasks on academic performance in a severe childhood stroke victim.

    PubMed

    Koegel, L K; Koegel, R L

    1986-01-01

    We examined the effects of task-sequencing variables on the academic performance of an 8-year-old severe stroke victim. Within a multiple baseline design, previously acquired (maintenance) task trials were systematically interspersed at designated points in treatment among new (acquisition) task trials. The results showed improvements in both academic responding and subjective ratings of motivation in each of four treated areas (spelling, reading, word-finding, and memory). Social validation data obtained from standardized school placement examinations suggested marked improvement in a variety of related areas of academic functioning. Results suggest that children suffering severe strokes may be capable of learning more than has previously been suspected, and that behavioral treatments may improve such children's functioning.

  2. Several practical issues toward implementing myoelectric pattern recognition for stroke rehabilitation.

    PubMed

    Li, Yun; Chen, Xiang; Zhang, Xu; Zhou, Ping

    2014-06-01

    High density surface electromyogram (sEMG) recording and pattern recognition techniques have demonstrated that substantial motor control information can be extracted from neurologically impaired muscles. In this study, a series of pattern recognition parameters were investigated in classification of 20 different movements involving the affected limb of 12 chronic stroke subjects. The experimental results showed that classification performance could be improved with spatial filtering and be maintained with a limited number of electrodes. It was also found that appropriate adjustment of analysis window length, sampling rate, and high-pass cut-off frequency in sEMG conditioning and processing would be potentially useful in reducing computational cost and meanwhile ensuring classification performance. The quantitative analyses are useful for practical myoelectric control toward improved stroke rehabilitation.

  3. Functional electrical stimulation therapy for recovery of reaching and grasping in severe chronic pediatric stroke patients.

    PubMed

    Kapadia, Naaz M; Nagai, Mary K; Zivanovic, Vera; Bernstein, Janet; Woodhouse, Janet; Rumney, Peter; Popovic, Milos R

    2014-04-01

    Stroke affects 2.7 children per 100,000 annually, leaving many of them with lifelong residual impairments despite intensive rehabilitation. In the present study the authors evaluated the effectiveness of 48 hours of transcutaneous functional electrical stimulation therapy for retraining voluntary reaching and grasping in 4 severe chronic pediatric stroke participants. Participants were assessed using the Rehabilitation Engineering Laboratory Hand Function Test, Quality of Upper Extremity Skills Test, Pediatric Evaluation of Disability Inventory, and Assisting Hand Assessment. All participants improved on all measures. The average change scores on selected Rehabilitation Engineering Laboratory Hand Function Test components were 14.5 for object manipulation (P = .042), 0.78 Nm for instrumented cylinder (P = .068), and 14 for wooden blocks (P = .068) and on the grasp component of Quality of Upper Extremity Skills Test was 25.93 (P = .068). These results provide preliminary evidence that functional electrical stimulation therapy has the potential to improve upper limb function in severe chronic pediatric stroke patients. PMID:23584687

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

    PubMed Central

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

    2016-01-01

    Objective To compare the swallowing characteristics of dysphagic patients with traumatic brain injury (TBI) with those of dysphagic stroke patients. Methods 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. Results 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). Conclusion 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. PMID:27446779

  5. Safety and Efficacy of Acute Clopidogrel Load in Patients with Moderate and Severe Ischemic Strokes

    PubMed Central

    Monlezun, Dominique J.; Rincon, Natalia; Tiu, Jonathan; Valmoria, Melisa

    2016-01-01

    Objective. To study the safety and efficacy of a clopidogrel loading dose in patients with moderate and severe acute ischemic strokes. Background. The safety of clopidogrel loading has been extensively investigated in patients with minor strokes and transient ischemic attacks. Methods. Acute ischemic stroke patients presenting consecutively to our center from 07/01/08 to 07/31/13 were screened. Clopidogrel loading was defined as at least 300 mg dose (with or without aspirin) given within 6 hours of admission. We compared outcomes in patients with baseline NIHSS > 3 with and without clopidogrel loading. Results. Inclusion criteria were met for 1011 patients (43.6% females, 69.1% black, median age 63). Patients with clopidogrel loading had lower baseline NIHSS than patients who were not loaded (8 versus 9, p = 0.005). The two groups had similar risk for hemorrhagic transformation (p = 0.918) and symptomatic hemorrhage (p = 0.599). Patients who were loaded had a lower rate of neurological worsening (38.9% versus 48.3%, p = 0.031) and less in-hospital mortality (4.3% versus 13.4%, p = 0.001) compared to those who were not loaded. The likelihood of having a poor functional outcome did not differ between the two groups after adjusting for NIHSS on admission (OR = 0.71, 95% CI 0.4633–1.0906, p = 0.118). Conclusion. Clopidogrel loading dose was not associated with increased risk for hemorrhagic transformation or symptomatic intracranial hemorrhage in our retrospective study and was associated with reduced rates of neuroworsening following moderate and severe stroke.

  6. Severity of Spatial Neglect During Acute Inpatient Rehabilitation Predicts Community Mobility After Stroke

    PubMed Central

    Oh-Park, Mooyeon; Hung, Cynthia; Chen, Peii; Barrett, A.M.

    2014-01-01

    Objective To examine whether stroke survivors with more severe spatial neglect during their acute inpatient rehabilitation had poorer mobility after returning to their communities. Design A prospective observational study. Setting Acute inpatient rehabilitation and follow-up in the community. Participants Thirty-one consecutive stroke survivors with right-brain damage (women, n = 15 [48.4%]), with the mean (standard deviation) age of 60 ± 11.5 years, were included in the study if they demonstrated spatial neglect within 2 months after stroke. Methods Spatial neglect was assessed with the Behavioral Inattention Test (BIT) (range, 0-146 [a lower score indicates more severity]) and the Catherine Bergego Scale (range, 0-30 [a higher score indicates more severity]). A score of the Behavioral Inattention Test <129 or of the Catherine Bergego Scale >0 defined the presence of spatial neglect. Main Outcome Measurements The outcome measure is community mobility, defined by the extent and frequency of traveling within the home and in the community, and is assessed with the University of Alabama at Birmingham Study of Aging Life-Space Assessment (range, 0-120 [a lower score indicates less mobile]). This measure was assessed after participants returned home ≥6 months after stroke. The covariates were age, gender, functional independence at baseline; follow-up interval; and depressed mood, which may affect the relationship between spatial neglect and community mobility. Results A lower Behavioral Inattention Test score was a significant predictor of a lower Life-Space Assessment score after controlling for all the covariates (β = 0.009 [95% confidence interval, 0.008-0.017]); P = .020). The proportion of participants unable to travel independently beyond their homes was 0%, 27.3%, and 72.7% for those with mild, moderate, and severe acute neglect, respectively (Catherine Bergego Scale range, 1-10, 11-20, and 21-30, respectively). Conclusions Our result indicates that acute

  7. The causality quandary in a patient with stroke, Takotsubo syndrome and severe coronary artery disease.

    PubMed

    Y-Hassan, Shams; Winter, Reidar; Henareh, Loghman

    2015-01-01

    Takotsubo-like left ventricular dysfunction syndrome (TLVDS) and acute coronary syndrome have almost always the same clinical presentation and ECG findings. Both diseases may become a potential cardioembolic source to the cerebrovascular system. Stroke has been linked to TLVDS either as the trigger or as a complication. We report on a 67-year-old female patient who presented with an acute ischemic stroke confirmed by computed tomographic scan of the brain. She also had electrocardiographic features and laboratory findings suggestive of both acute myocardial infarction (AMI) and TLVDS. Coronary angiography revealed severe coronary artery stenoses but the coronary lesions did not have any of the features suggestive of an acute pathology. Echocardiography and left ventriculography showed a striking apical ballooning of the left ventricle, which resolved completely within 1 week, a clinical picture and course typical for TLVDS. There were no signs of left ventricular thrombus. A few burning questions arose from this case: what was the acute cardiac disease - TLVDS or AMI? Which disease came first - the stroke or the acute cardiac illness? An intricate cause-effect relationship is discussed; and finally, does an obstructive coronary artery disease rule out TLVDS?

  8. Decoding of motor intentions from epidural ECoG recordings in severely paralyzed chronic stroke patients

    NASA Astrophysics Data System (ADS)

    Spüler, M.; Walter, A.; Ramos-Murguialday, A.; Naros, G.; Birbaumer, N.; Gharabaghi, A.; Rosenstiel, W.; Bogdan, M.

    2014-12-01

    Objective. Recently, there have been several approaches to utilize a brain-computer interface (BCI) for rehabilitation with stroke patients or as an assistive device for the paralyzed. In this study we investigated whether up to seven different hand movement intentions can be decoded from epidural electrocorticography (ECoG) in chronic stroke patients. Approach. In a screening session we recorded epidural ECoG data over the ipsilesional motor cortex from four chronic stroke patients who had no residual hand movement. Data was analyzed offline using a support vector machine (SVM) to decode different movement intentions. Main results. We showed that up to seven hand movement intentions can be decoded with an average accuracy of 61% (chance level 15.6%). When reducing the number of classes, average accuracies up to 88% can be achieved for decoding three different movement intentions. Significance. The findings suggest that ipsilesional epidural ECoG can be used as a viable control signal for BCI-driven neuroprosthesis. Although patients showed no sign of residual hand movement, brain activity at the ipsilesional motor cortex still shows enough intention-related activity to decode different movement intentions with sufficient accuracy.

  9. Serum Levels of Substance P and Mortality in Patients with a Severe Acute Ischemic Stroke.

    PubMed

    Lorente, Leonardo; Martín, María M; Almeida, Teresa; Pérez-Cejas, Antonia; Ramos, Luis; Argueso, Mónica; Riaño-Ruiz, Marta; Solé-Violán, Jordi; Hernández, Mariano

    2016-01-01

    Substance P (SP), a member of tachykinin family, is involved in the inflammation of the central nervous system and in the appearance of cerebral edema. Higher serum levels of SP have been found in 18 patients with cerebral ischemia compared with healthy controls. The aim of our multi-center study was to analyze the possible association between serum levels of SP and mortality in ischemic stroke patients. We included patients with malignant middle cerebral artery infarction (MMCAI) and a Glasgow Coma Scale (GCS) lower than 9. Non-surviving patients at 30 days (n = 31) had higher serum concentrations of SP levels at diagnosis of severe MMCAI than survivors (n = 30) (p < 0.001). We found in multiple regression an association between serum concentrations of SP higher than 362 pg/mL and mortality at 30 days (Odds Ratio = 5.33; 95% confidence interval = 1.541-18.470; p = 0.008) after controlling for age and GCS. Thus, the major novel finding of our study was the association between serum levels of SP and mortality in patients suffering from severe acute ischemic stroke. PMID:27338372

  10. Serum Levels of Substance P and Mortality in Patients with a Severe Acute Ischemic Stroke

    PubMed Central

    Lorente, Leonardo; Martín, María M.; Almeida, Teresa; Pérez-Cejas, Antonia; Ramos, Luis; Argueso, Mónica; Riaño-Ruiz, Marta; Solé-Violán, Jordi; Hernández, Mariano

    2016-01-01

    Substance P (SP), a member of tachykinin family, is involved in the inflammation of the central nervous system and in the appearance of cerebral edema. Higher serum levels of SP have been found in 18 patients with cerebral ischemia compared with healthy controls. The aim of our multi-center study was to analyze the possible association between serum levels of SP and mortality in ischemic stroke patients. We included patients with malignant middle cerebral artery infarction (MMCAI) and a Glasgow Coma Scale (GCS) lower than 9. Non-surviving patients at 30 days (n = 31) had higher serum concentrations of SP levels at diagnosis of severe MMCAI than survivors (n = 30) (p < 0.001). We found in multiple regression an association between serum concentrations of SP higher than 362 pg/mL and mortality at 30 days (Odds Ratio = 5.33; 95% confidence interval = 1.541–18.470; p = 0.008) after controlling for age and GCS. Thus, the major novel finding of our study was the association between serum levels of SP and mortality in patients suffering from severe acute ischemic stroke. PMID:27338372

  11. Protection against Experimental Stroke by Ganglioside GM1 Is Associated with the Inhibition of Autophagy

    PubMed Central

    Li, Li; Tian, Jinghua; Long, Mitchell King-Wei; Chen, Yong; Lu, Jianfei; Zhou, Changman; Wang, Tianlong

    2016-01-01

    Ganglioside GM1, which is particularly abundant in the central nervous system (CNS), is closely associated with the protection against several CNS disorders. However, controversial findings have been reported on the role of GM1 following ischemic stroke. In the present study, using a rat middle cerebral artery occlusion (MCAO) model, we investigated whether GM1 can protect against ischemic brain injury and whether it targets the autophagy pathway. GM1 was delivered to Sprague-Dawley male rats at 3 doses (25 mg/kg, 50 mg/kg, 100 mg/kg) by intraperitoneal injection soon after reperfusion and then once daily for 2 days. The same volume of saline was given as a control. Tat–Beclin-1, a specific autophagy inducer, was administered by intraperitoneal injection at 24 and 48 hours post-MCAO. Infarction volume, mortality and neurological function were assessed at 72 hours after ischemic insult. Immunofluorescence and Western blotting were performed to determine the expression of autophagy-related proteins P62, LC3 and Beclin-1 in the penumbra area. No significant changes in mortality and physiological variables (heart rate, blood glucose levels and arterial blood gases) were observed between the different groups. However, MCAO resulted in enhanced conversion of LC3-I into LC3-II, P62 degradation, high levels of Beclin-1, a large area infarction (26.3±3.6%) and serious neurobehavioral deficits. GM1 (50 mg/kg) treatment significantly reduced the autophagy activation, neurobehavioral dysfunctions, and infarction volume (from 26.3% to 19.5%) without causing significant adverse side effects. However, this biological function could be abolished by Tat–Beclin-1. In conclusion: GM1 demonstrated safe and robust neuroprotective effects that are associated with the inhibition of autophagy following experimental stroke. PMID:26751695

  12. Blocking Sympathetic Nervous System Reverses Partially Stroke-Induced Immunosuppression but does not Aggravate Functional Outcome After Experimental Stroke in Rats.

    PubMed

    Deng, Qi-Wen; Yang, Heng; Yan, Fu-Ling; Wang, Huan; Xing, Fang-Lan; Zuo, Lei; Zhang, Han-Qing

    2016-08-01

    Stoke results in activation of the sympathetic nervous system (SNS), inducing systemic immunosuppression. However, the potential mechanisms underlying stroke-induced immunosuppression remain unclear. Here, we determined the SNS effects on functional outcome and explored the interactions among SNS, β-arrestin2 and nuclear factor-κB (NF-κB) after experimental stroke in rats. In the current study, stroke was induced by a transient middle cerebral artery occlusion (MCAO) in rats, and SNS activity was inhibited by intraperitoneal injection of 6-hydroxydopamine HBr (6-OHDA). 7.0 T Micro-MRI and Longa score were employed to assess the functional outcome after stroke. Flow cytometry and ELISA assay were used to measure the expression of MHC class II, tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). Western blot was conducted to analyze β-arrestin2 and NF-κB protein expression levels after experimental stroke. We found significantly increased infarct volumes and functional impairment after MCAO at different post-surgery time points, which were not aggravated by 6-OHDA treatment. SNS blockade partially reversed the expression of MHC class II after stroke over time, as well as TNF-α and IFN-γ levels in lipopolysaccharide-stimulated macrophages in vitro. Treatment of MCAO rats with SNS-inhibitor significantly diminished NF-κB activation and enhanced β-arrestin2 expression after stroke. This study suggests that pharmacological SNS inhibition dose not aggravate functional outcome after stroke. Stroke-induced immunosuppression may be involved in the SNS-β-arrestin2-NF-κB pathway. PMID:27059792

  13. Somatosensory and Brainstem Auditory Evoked Potentials Assessed between 4 and 7 Days after Severe Stroke Onset Predict Unfavorable Outcome.

    PubMed

    Zhang, Yan; Su, Ying Ying; Xiao, Shu Ying; Liu, Yi Fei

    2015-01-01

    Our objective was to explore the best predictive timing of short-latency somatosensory evoked potentials (SLSEP) and brainstem auditory evoked potentials (BAEP) for unfavorable outcomes in patients with early stage severe stroke. One hundred fifty-six patients with acute severe supratentorial stroke were monitored according to SLSEP, BAEP, and the Glasgow Coma Scale (GCS) at 1-3 days and 4-7 days after the onset of stroke. All patients were followed up for outcomes at 6 months after onset using the modified Rankin Scale (mRS), with a score of 5-6 considered unfavorable. The predictive values of SLSEP, BAEP, and the GCS at 1-3 days were compared with 4-7 days after onset. Our results show that, according to the analysis of prognostic authenticity, the predictive values of SLSEP and BAEP at 4-7 days after stroke onset improved when compared with the values at 1-3 days for unfavorable outcomes. Most of the patients with change of worsening evoked potentials from 1-3 days to 4-7 days after onset had unfavorable outcomes. In conclusion, SLSEP and BAEP assessed at 4-7 days after onset predicted unfavorable outcomes for acute severe stroke patients. The worsening values of SLSEP and BAEP between 1-3 days and 4-7 days also present a prognostic value.

  14. Percutaneous Recanalization of Acute Internal Carotid Artery Occlusions in Patients with Severe Stroke

    SciTech Connect

    Dabitz, Rainer; Triebe, Stefan; Leppmeier, Ullrich; Ochs, Guenther; Vorwerk, Dierk

    2007-02-15

    Background. Sudden symptomatic occlusions of the proximal internal carotid artery (ICA) resulting in severe middle cerebral artery (MCA) ischemia and stroke are usually not accessible by rt-PA thrombolysis and the prognosis is usually very poor. Mechanical recanalization of the proximal ICA combined with intravenous and intra-arterial thrombolysis was therefore used as a rescue procedure. Methods. Ten patients (9 men, 1 woman; mean age 56.1 years) were treated with emergency recanalization of the proximal carotid artery by using stents and/or balloon angioplasty as a rescue procedure. Three patients showed dissection, and 7 had atherothrombotic occlusions. Nine of 10 presented with an initial modified Rankin Scale (mRS) of 5, the remaining patient with mRS 4 (average NIHSS 21.4). After sonographic confirmation of ICA with associated MCA/distal ICA occlusion and bridging with rt-PA (without abciximab) an emergency angiography was performed with subsequent mechanical recanalization by percutaneous transluminal angioplasty (PTA) (n = 1) or primary stenting (n = 9) using self-expanding stents. Distal protection was used in 1 of 10 patients. Results. Recanalization of the proximal ICA was achieved in all. At least partial recanalization of the intracerebral arteries was achieved in all, and complete recanalization in 5. In 4 of 10 patients limited hemorrhage was detected during CT controls. Major complications included 2 patients who had to undergo hemicraniectomy. One patient died from malignant infarction. At the time of discharge from the stroke unit 9 of 10 patients had improved markedly, 5 patients having an mRS of {<=}2, and 3 patients a mRS of 3. At control after a mean of 20 weeks, 7 of 8 (88%) patients had a mRS {<=}2, and 1 a mRS of 3. Conclusions. Primary mechanical recanalization of ICA occlusions by stent and PTA combined with fibrinolysis and/or GPIIb/IIIa-receptor antagonists seems to be feasible to improve patient outcome significantly.

  15. Altered hypothalamic inflammatory gene expression correlates with heat stroke severity in a conscious rodent model.

    PubMed

    Audet, Gerald N; Dineen, Shauna M; Quinn, Carrie M; Leon, Lisa R

    2016-04-15

    It has been suggested that heat-induced hypothalamic damage mediates core temperature (Tc) disturbances during heat stroke (HS) recovery; this is significant as hypothermia and/or fever have been linked to severity and overall pathological insult. However, to date there has been a lack of histological evidence in support of these claims. We hypothesized that local hypothalamic cytokines and/or chemokines, known regulators of Tc, are mediating the elevation in Tc during HS recovery even in the absence of histological damage. In experiment 1, the hypothalamus of Fischer 344 rats was examined for 84 cytokine/chemokine genes (real-time PCR) at multiple time points (Tc,Max, 1, 3, and 10 days) during mild HS recovery. In experiment 2, the hypothalamus of three different HS severities (MILD, moderate [MOD], and severe [SEV]) in rats were examined for the same genes as experiment 1 as well as six oxidative damage markers, at a single intermediate time point (1 day). Systemic cytokines were also analyzed in experiment 2 across the three severities. There were significant alterations in 25 cytokines/chemokines expression at Tc,Max, but little or no changes in expression at longer time points in experiment 1. In experiment 2 there were significant changes in gene expression in SEV rats only, with MILD and MOD rats showing baseline expression at 1 day, despite an absence of systemic cytokine expression in any severity. There was also no change in any oxidative marker of damage at 1 day, regardless of severity. In conclusion, we show only limited changes during long term recovery from HS, but demonstrate differences in hypothalamic gene expression patterns that may be driving HS pathology and morbidity. These findings contribute to our overall understanding of HS pathology in the CNS, as well as providing avenues for future pharmacological intervention. PMID:26876741

  16. Stroke

    MedlinePlus

    ... a clot within a blood vessel of the brain or neck, called thrombosis the movement of a clot from ... body, such as from the heart to the neck or brain, called an embolism a severe narrowing of an ...

  17. Genetic variation in retinal vascular patterning predicts variation in pial collateral extent and stroke severity.

    PubMed

    Prabhakar, Pranay; Zhang, Hua; Chen, De; Faber, James E

    2015-01-01

    The presence of a native collateral circulation in tissues lessens injury in occlusive vascular diseases. However, differences in genetic background cause wide variation in collateral number and diameter in mice, resulting in large variation in protection. Indirect estimates of collateral perfusion suggest that wide variation also exists in humans. Unfortunately, methods used to obtain these estimates are invasive and not widely available. We sought to determine whether differences in genetic background in mice result in variation in branch patterning of the retinal arterial circulation, and whether these differences predict strain-dependent differences in pial collateral extent and severity of ischemic stroke. Retinal patterning metrics, collateral extent, and infarct volume were obtained for 10 strains known to differ widely in collateral extent. Multivariate regression was conducted, and model performance was assessed using K-fold cross-validation. Twenty-one metrics varied with strain (p<0.01). Ten metrics (e.g., bifurcation angle, lacunarity, optimality) predicted collateral number and diameter across seven regression models, with the best model closely predicting (p<0.0001) number (±1.2-3.4 collaterals, K-fold R2=0.83-0.98), diameter (±1.2-1.9 μm, R2=0.73-0.88), and infarct volume (±5.1 mm3, R2=0.85-0.87). An analogous set of the most predictive metrics, obtained for the middle cerebral artery (MCA) tree in a subset of the above strains, also predicted (p<0.0001) collateral number (±3.3 collaterals, K-fold R2=0.78) and diameter (±1.6 μm, R2=0.86). Thus, differences in arterial branch patterning in the retina and the MCA trees are specified by genetic background and predict variation in collateral extent and stroke severity. If also true in human, and since genetic variation in cerebral collaterals extends to other tissues at least in mice, a similar "retinal predictor index" could serve as a non- or minimally invasive biomarker for collateral extent in

  18. Improved Therapeutic Benefits by Combining Physical Cooling With Pharmacological Hypothermia After Severe Stroke in Rats

    PubMed Central

    Lee, Jin Hwan; Wei, Ling; Gu, Xiaohuan; Won, Soonmi; Wei, Zheng Zachory; Dix, Thomas A.

    2016-01-01

    Background and Purpose— Therapeutic hypothermia is a promising strategy for treatment of acute stroke. Clinical translation of therapeutic hypothermia, however, has been hindered because of the lack of efficiency and adverse effects. We sought to enhance the clinical potential of therapeutic hypothermia by combining physical cooling (PC) with pharmacologically induced hypothermia after ischemic stroke. Methods— Wistar rats were subjected to 90-minute middle cerebral artery occlusion by insertion of an intraluminal filament. Mild-to-moderate hypothermia was induced 120 minutes after the onset of stroke by PC alone, a neurotensin receptor 1 (NTR1) agonist HPI-201 (formally ABS-201) alone or the combination of both. The outcomes of stroke were evaluated at 3 and 21 days after stroke. Results— PC or HPI-201 each showed hypothermic effect and neuroprotection in stroke rats. The combination of PC and HPI-201 exhibited synergistic effects in cooling process, reduced infarct formation, cell death, and blood-brain barrier damages and improved functional recovery after stroke. Importantly, coapplied HPI-201 completely inhibited PC-associated shivering and tachycardia. Conclusions— The centrally acting hypothermic drug HPI-201 greatly enhanced the efficiency and efficacy of conventional PC; this combined cooling therapy may facilitate clinical translation of hypothermic treatment for stroke. PMID:27301934

  19. [Withdrawal of artificial nutrition and hydration in severe stroke: medical, legal and ethical considerations].

    PubMed

    Tannier, C; Crozier, S; Zuber, M; Constantinides, Y; Delezie, E; Gisquet, E; Grignoli, N; Lamy, C; Louvet, F; Pinel, J-F

    2015-02-01

    In the majority of cases, severe stroke is accompanied by difficulty in swallowing and an altered state of consciousness requiring artificial nutrition and hydration. Because of their artificial nature, nutrition and hydration are considered by law as treatment rather basic care. Withdrawal of these treatments is dictated by the refusal of unreasonable obstinacy enshrined in law and is justified by the risk of severe disability and very poor quality of life. It is usually the last among other withholding and withdrawal decisions which have already been made during the long course of the disease. Reaching a collegial consensus on a controversial decision such as artificial nutrition and hydration withdrawal is a difficult and complex process. The reluctance for such decisions is mainly due to the symbolic value of food and hydration, to the fear of "dying badly" while suffering from hunger and thirst, and to the difficult distinction between this medical act and euthanasia. The only way to overcome such reluctance is to ensure flawless accompaniment, associating sedation and appropriate comfort care with a clear explanation (with relatives but also caregivers) of the rationale and implications of this type of decision. All teams dealing with this type of situation must have thoroughly thought through the medical, legal and ethical considerations involved in making this difficult decision.

  20. Machine-based, self-guided home therapy for individuals with severe arm impairment after stroke: a randomized controlled trial

    PubMed Central

    Zondervan, DK; Augsburger, R; Bodenhoefer, B; Friedman, N; Reinkensmeyer, DJ; Cramer, SC

    2015-01-01

    Background Few therapeutic options exist for the millions of persons living with severe arm impairment after stroke to increase their dose of arm rehabilitation. This study compared self-guided, high-repetition home therapy with a mechanical device (the Resonating Arm Exerciser - RAE) to conventional therapy in patients with chronic stroke, and explored RAE use for patients with subacute stroke. Methods Sixteen participants with severe upper extremity impairment (mean Fugl-Meyer (FM) score = 21.4 ± 8.8 out of 66) > 6 months post stroke were randomized to three-weeks of exercise with RAE or conventional exercises. Primary outcome measure was FM score one month post-therapy. Secondary outcome measures included MAL, Visual Analog Pain scale, and Ashworth spasticity scale. After a one-month break, individuals in the conventional group also received a three-week course of RAE therapy. Results The change in FM score was significant in both the RAE and conventional groups after training (2.6 ± 1.4 and 3.4 ± 2.4, p = 0.008 and 0.016, respectively). These improvements were not significant at one-month. Exercise with RAE led to significantly greater improvements in distal FM score than conventional therapy at the one-month follow-up (p = 0.02). In a separate cohort of patients with subacute stroke, RAE was found feasible for exercise. Discussion In subjects with severe arm impairment after chronic stroke, home-based training with RAE was feasible and significantly reduced impairment without increasing pain or spasticity. Gains with RAE were comparable to those found with conventional training, and also included distal arm improvement. PMID:25273359

  1. Neuroprotective properties and mechanisms of resveratrol in in vitro and in vivo experimental cerebral stroke models.

    PubMed

    Singh, Nilendra; Agrawal, Megha; Doré, Sylvain

    2013-08-21

    Resveratrol, a natural stilbene present at relatively high concentrations in grape skin and seeds and red wine, is known for its purported antioxidant activity in the vascular and nervous systems. In contrast to its direct antioxidant role within the central nervous system, recent research supports a protective mechanism through increasing endogenous cellular antioxidant defenses, which triggers a cascade of parallel neuroprotective pathways. A growing body of in vitro and in vivo evidence indicates that resveratrol acts through multiple pathways and reduces ischemic damage in vital organs, such as the heart and the brain, in various rodent models. Most of the protective biological actions of resveratrol have been associated with its antioxidative, anti-inflammatory, and antiapoptotic properties and other indirect pathways. Continued public interest and increasing resveratrol supplements on the market warrant a review of the available in vitro and in vivo science reported in the stroke-related literature. Rigorous clinical trials evaluating the effects of resveratrol in stroke are absent, though the general population consumption appears to be relatively safe. Resveratrol has shown potential for treating stroke in laboratory animals and in vitro human cell studies, yet there is still a need for human research in preclinical settings. This review summarizes many of the findings on the neuroprotective potential of resveratrol in cerebral stroke, focusing on both the in vitro and in vivo experimental models and some proposed mechanisms of action.

  2. Severe envenomation by Cerastes cerastes viper: an unusual mechanism of acute ischemic stroke.

    PubMed

    Rebahi, Houssam; Nejmi, Hicham; Abouelhassan, Taoufik; Hasni, Khadija; Samkaoui, Mohamed-Abdenasser

    2014-01-01

    Cerebral complications after snake bites--particularly ischemic complications--are rare. Very few cases of cerebral infarction resulting from a viper bite have been reported, and we call attention to this uncommon etiology. We discuss 3 authenticated reports of acute ischemic cerebrovascular accidents after 3 typical severe envenomations by Cerastes cerastes vipers. The 3 patients developed extensive local swelling and life-threatening systemic envenomation characterized by disseminated intravascular coagulopathy, increased fibrinolysis, thrombocytopenia, microangiopathic hemolytic anemia, and acute renal failure. This clinical picture involved atypical neurologic manifestations. These patients had either low Glasgow Coma Scale (GCS) or hemiparesis within hours to 4 days after being bitten, and they were found to have computed tomographic evidence of single or multiple ischemic (nonhemorrhagic) strokes of small- to large-vessel territories of the brain. One patient had good clinical recovery without neurologic deficits. Thrombotic complications occurred an average of 36 hours after being bitten, and their importance depends on the degree of envenomation. The possible mechanisms for cerebral infarction in these cases include generalized prothrombotic action of the venom (consumptive coagulopathy), toxin-induced vasculitis, and endothelial damage.

  3. Clearance of serum solutes by hemofiltration in dogs with severe heat stroke

    PubMed Central

    2014-01-01

    Background We have previously reported that hemofiltration (HF) may be an effective additional means of treating heat stroke when rapid cooling is not effective. Methods Dogs were assigned to a heat stroke (control) or heat stroke + hemofiltration (HF) group (n = 8 each group). After heat stroke induction, dogs in the HF group received HF for 3 h. Serum concentrations of interleukin (IL)-10, tumor necrosis factor (TNF)-α, IL-6, blood urea nitrogen (BUN) and creatinine were measured at baseline and 1, 2, and 3 h after heat stroke. Clearance rates of solutes were determined 1, 2, and 3 h after the start of HF. Results Serum concentrations of all solutes tended to increase with time after heat stroke in the control group, but decreased (BUN, creatinine) or remained relatively unchanged (TNF-α, IL-6, IL-10) with time in the HF group. Concentrations of all solutes were significantly lower in the HF group compared with the control group at 2 and 3 h (P < 0.05). Clearance rates for small molecular weight solutes were high, while those for larger molecular weight solutes were low. Conclusion HF prevents heat stroke-induced increases in serum cytokine concentrations and is effective for clearing small molecular weight solutes from serum, but less effective for clearing larger molecular weight solutes, including TNF-α, IL-6, and IL-10. PMID:25145441

  4. A novel snake venom-derived GPIb antagonist, anfibatide, protects mice from acute experimental ischaemic stroke and reperfusion injury

    PubMed Central

    Li, Ting-Ting; Fan, Man-Li; Hou, Shi-Xiang; Li, Xiao-Yi; Barry, Devin M; Jin, Hui; Luo, Sheng-Yong; Kong, Feng; Lau, Lit-Fui; Dai, Xiang-Rong; Zhang, Guo-Hui; Zhou, Lan-Lan

    2015-01-01

    Background and Purpose Ischaemic stroke is a serious disease with limited therapy options. Glycoprotein (GP)Ib binding to von Willebrand factor (vWF) exposed at vascular injury initiates platelet adhesion and contributes to platelet aggregation. GPIb has been suggested as an effective target for antithrombotic therapy in stroke. Anfibatide is a GPIb antagonist derived from snake venom and we investigated its protective effect on experimental brain ischaemia in mice. Experimental Approach Focal cerebral ischaemia was induced by 90 min of transient middle cerebral artery occlusion (MCAO). These mice were then treated with anfibatide (4, 2, 1 μg·kg−1), injected i.v., after 90 min of MCAO, followed by 1 h of reperfusion. Tirofiban, a GPIIb/IIIα antagonist, was used as a positive control. Key Results Twenty-four hours after MCAO, anfibatide-treated mice showed significantly improved ischaemic lesions in a dose-dependent manner. The mice had smaller infarct volumes, less severe neurological deficits and histopathology of cerebrum tissues compared with the untreated MCAO mice. Moreover, anfibatide decreased the amount of GPIbα, vWF and accumulation of fibrin(ogen) in the vasculature of the ischaemic hemisphere. Tirofiban had similar effects on infarct size and fibrin(ogen) deposition compared with the MCAO group. Importantly, the anfibatide-treated mice showed a lower incidence of intracerebral haemorrhage and shorter tail bleeding time compared with the tirofiban-treated mice. Conclusions and Implications Our data indicate anfibatide is a safe GPIb antagonist that exerts a protective effect on cerebral ischaemia and reperfusion injury. Anfibatide is a promising candidate that could be beneficial for the treatment of ischaemic stroke. PMID:25917571

  5. Multicenter Evaluation of Geometric Accuracy of MRI Protocols Used in Experimental Stroke

    PubMed Central

    Milidonis, Xenios; Lennen, Ross J.; Jansen, Maurits A.; Mueller, Susanne; Boehm-Sturm, Philipp; Holmes, William M.; Sena, Emily S.; Macleod, Malcolm R.; Marshall, Ian

    2016-01-01

    It has recently been suggested that multicenter preclinical stroke studies should be carried out to improve translation from bench to bedside, but the accuracy of magnetic resonance imaging (MRI) scanners routinely used in experimental stroke has not yet been evaluated. We aimed to assess and compare geometric accuracy of preclinical scanners and examine the longitudinal stability of one scanner using a simple quality assurance (QA) protocol. Six 7 Tesla animal scanners across six different preclinical imaging centers throughout Europe were used to scan a small structural phantom and estimate linear scaling errors in all orthogonal directions and volumetric errors. Between-scanner imaging consisted of a standard sequence and each center’s preferred sequence for the assessment of infarct size in rat models of stroke. The standard sequence was also used to evaluate the drift in accuracy of the worst performing scanner over a period of six months following basic gradient calibration. Scaling and volumetric errors using the standard sequence were less variable than corresponding errors using different stroke sequences. The errors for one scanner, estimated using the standard sequence, were very high (above 4% scaling errors for each orthogonal direction, 18.73% volumetric error). Calibration of the gradient coils in this system reduced scaling errors to within ±1.0%; these remained stable during the subsequent 6-month assessment. In conclusion, despite decades of use in experimental studies, preclinical MRI still suffers from poor and variable geometric accuracy, influenced by the use of miscalibrated systems and various types of sequences for the same purpose. For effective pooling of data in multicenter studies, centers should adopt standardized procedures for system QA and in vivo imaging. PMID:27603704

  6. Multicenter Evaluation of Geometric Accuracy of MRI Protocols Used in Experimental Stroke.

    PubMed

    Milidonis, Xenios; Lennen, Ross J; Jansen, Maurits A; Mueller, Susanne; Boehm-Sturm, Philipp; Holmes, William M; Sena, Emily S; Macleod, Malcolm R; Marshall, Ian

    2016-01-01

    It has recently been suggested that multicenter preclinical stroke studies should be carried out to improve translation from bench to bedside, but the accuracy of magnetic resonance imaging (MRI) scanners routinely used in experimental stroke has not yet been evaluated. We aimed to assess and compare geometric accuracy of preclinical scanners and examine the longitudinal stability of one scanner using a simple quality assurance (QA) protocol. Six 7 Tesla animal scanners across six different preclinical imaging centers throughout Europe were used to scan a small structural phantom and estimate linear scaling errors in all orthogonal directions and volumetric errors. Between-scanner imaging consisted of a standard sequence and each center's preferred sequence for the assessment of infarct size in rat models of stroke. The standard sequence was also used to evaluate the drift in accuracy of the worst performing scanner over a period of six months following basic gradient calibration. Scaling and volumetric errors using the standard sequence were less variable than corresponding errors using different stroke sequences. The errors for one scanner, estimated using the standard sequence, were very high (above 4% scaling errors for each orthogonal direction, 18.73% volumetric error). Calibration of the gradient coils in this system reduced scaling errors to within ±1.0%; these remained stable during the subsequent 6-month assessment. In conclusion, despite decades of use in experimental studies, preclinical MRI still suffers from poor and variable geometric accuracy, influenced by the use of miscalibrated systems and various types of sequences for the same purpose. For effective pooling of data in multicenter studies, centers should adopt standardized procedures for system QA and in vivo imaging. PMID:27603704

  7. The efficacy of SMART Arm training early after stroke for stroke survivors with severe upper limb disability: a protocol for a randomised controlled trial

    PubMed Central

    2013-01-01

    Background Recovery of upper limb function after stroke is poor. The acute to subacute phase after stroke is the optimal time window to promote the recovery of upper limb function. The dose and content of training provided conventionally during this phase is however, unlikely to be adequate to drive functional recovery, especially in the presence of severe motor disability. The current study concerns an approach to address this shortcoming, through evaluation of the SMART Arm, a non-robotic device that enables intensive and repetitive practice of reaching by stroke survivors with severe upper limb disability, with the aim of improving upper limb function. The outcomes of SMART Arm training with or without outcome-triggered electrical stimulation (OT-stim) to augment movement and usual therapy will be compared to usual therapy alone. Methods/Design A prospective, assessor-blinded parallel, three-group randomised controlled trial is being conducted. Seventy-five participants with a first-ever unilateral stroke less than 4 months previously, who present with severe arm disability (three or fewer out of a possible six points on the Motor Assessment Scale [MAS] Item 6), will be recruited from inpatient rehabilitation facilities. Participants will be randomly allocated to one of three dose-matched groups: SMART Arm training with OT-stim and usual therapy; SMART Arm training without OT-stim and usual therapy; or usual therapy alone. All participants will receive 20 hours of upper limb training over four weeks. Blinded assessors will conduct four assessments: pre intervention (0-weeks), post intervention (4-weeks), 26 weeks and 52 weeks follow-up. The primary outcome measure is MAS item 6. All analyses will be based on an intention-to-treat principle. Discussion By enabling intensive and repetitive practice of a functional upper limb task during inpatient rehabilitation, SMART Arm training with or without OT-stim in combination with usual therapy, has the potential to

  8. Combining Robotic Training and Non-Invasive Brain Stimulation in Severe Upper Limb-Impaired Chronic Stroke Patients

    PubMed Central

    Di Lazzaro, Vincenzo; Capone, Fioravante; Di Pino, Giovanni; Pellegrino, Giovanni; Florio, Lucia; Zollo, Loredana; Simonetti, Davide; Ranieri, Federico; Brunelli, Nicoletta; Corbetto, Marzia; Miccinilli, Sandra; Bravi, Marco; Milighetti, Stefano; Guglielmelli, Eugenio; Sterzi, Silvia

    2016-01-01

    Previous studies suggested that both robot-assisted rehabilitation and non-invasive brain stimulation can produce a slight improvement in severe chronic stroke patients. It is still unknown whether their combination can produce synergistic and more consistent improvements. Safety and efficacy of this combination has been assessed within a proof-of-principle, double-blinded, semi-randomized, sham-controlled trial. Inhibitory continuous Theta Burst Stimulation (cTBS) was delivered on the affected hemisphere, in order to improve the response to the following robot-assisted therapy via a homeostatic increase of learning capacity. Twenty severe upper limb-impaired chronic stroke patients were randomized to robot-assisted therapy associated with real or sham cTBS, delivered for 10 working days. Eight real and nine sham patients completed the study. Change in Fugl-Meyer was chosen as primary outcome, while changes in several quantitative indicators of motor performance extracted by the robot as secondary outcomes. The treatment was well-tolerated by the patients and there were no adverse events. All patients achieved a small, but significant, Fugl-Meyer improvement (about 5%). The difference between the real and the sham cTBS groups was not significant. Among several secondary end points, only the Success Rate (percentage of targets reached by the patient) improved more in the real than in the sham cTBS group. This study shows that a short intensive robot-assisted rehabilitation produces a slight improvement in severe upper-limb impaired, even years after the stroke. The association with homeostatic metaplasticity-promoting non-invasive brain stimulation does not augment the clinical gain in patients with severe stroke. PMID:27013950

  9. Experimental Evaluation of a Method for Turbocharging Four-Stroke, Single Cylinder, Internal Combustion Engines

    NASA Astrophysics Data System (ADS)

    Buchman, Michael; Winter, Amos

    2015-11-01

    Turbocharging an engine increases specific power, improves fuel economy, reduces emissions, and lowers cost compared to a naturally aspirated engine of the same power output. These advantages make turbocharging commonplace for multi-cylinder engines. Single cylinder engineers are not commonly turbocharged due to the phase lag between the exhaust stroke, which powers the turbocharger, and the intake stroke, when air is pumped into the engine. Our proposed method of turbocharging single cylinder engines is to add an ``air capacitor'' to the intake manifold, an additional volume that acts as a buffer to store compressed air between the exhaust and intake strokes, and smooth out the pressure pulses from the turbocharger. This talk presents experimental results from a single cylinder, turbocharged diesel engine fit with various sized air capacitors. Power output from the engine was measured using a dynamometer made from a generator, with the electrical power dissipated with resistive heating elements. We found that intake air density increases with capacitor size as theoretically predicted, ranging from 40 to 60 percent depending on heat transfer. Our experiment was able to produce 29 percent more power compared to using natural aspiration. These results validated that an air capacitor and turbocharger may be a simple, cost effective means of increasing the power density of single cylinder engines.

  10. Progesterone treatment for experimental stroke: an individual animal meta-analysis.

    PubMed

    Wong, Raymond; Renton, Cheryl; Gibson, Claire L; Murphy, Stephanie J; Kendall, David A; Bath, Philip M W

    2013-09-01

    Preclinical studies suggest progesterone is neuroprotective after cerebral ischemia. The gold standard for assessing intervention effects across studies within and between subgroups is to use meta-analysis based on individual animal data (IAD). Preclinical studies of progesterone in experimental stroke were identified from searches of electronic databases and reference lists. Corresponding authors of papers of interest were contacted to obtain IAD and, if unavailable, summary data were obtained from the publication. Data are given as standardized mean differences (SMDs, continuous data) or odds ratios (binary data), with 95% confidence intervals (95% CIs). In an unadjusted analysis of IAD and summary data, progesterone reduced standardized lesion volume (SMD -0.766, 95% CI -1.173 to -0.358, P<0.001). Publication bias was apparent on visual inspection of a Begg's funnel plot on lesion volume and statistically using Egger's test (P=0.001). Using individual animal data alone, progesterone was associated with an increase in death in adjusted analysis (odds ratio 2.64, 95% CI 1.17 to 5.97, P=0.020). Although progesterone significantly reduced lesion volume, it also appeared to increase the incidence of death after experimental stroke, particularly in young ovariectomized female animals. Experimental studies must report the effect of interactions on death and on modifiers, such as age and sex.

  11. Effects of Tetramethylpyrazine on Functional Recovery and Neuronal Dendritic Plasticity after Experimental Stroke

    PubMed Central

    Lin, Jun-Bin; Zheng, Chan-Juan; Zhang, Xuan; Chen, Juan; Liao, Wei-Jing; Wan, Qi

    2015-01-01

    The 2,3,5,6-tetramethylpyrazine (TMP) has been widely used in the treatment of ischemic stroke by Chinese doctors. Here, we report the effects of TMP on functional recovery and dendritic plasticity after ischemic stroke. A classical model of middle cerebral artery occlusion (MCAO) was established in this study. The rats were assigned into 3 groups: sham group (sham operated rats treated with saline), model group (MCAO rats treated with saline) and TMP group (MCAO rats treated with 20 mg/kg/d TMP). The neurological function test of animals was evaluated using the modified neurological severity score (mNSS) at 3 d, 7 d, and 14 d after MCAO. Animals were euthanized for immunohistochemical labeling to measure MAP-2 levels in the peri-infarct area. Golgi-Cox staining was performed to test effect of TMP on dendritic plasticity at 14 d after MCAO. TMP significantly improved neurological function at 7 d and 14 d after ischemia, increased MAP-2 level at 14 d after ischemia, and enhanced spine density of basilar dendrites. TMP failed to affect the spine density of apical dendrites and the total dendritic length. Data analyses indicate that there was significant negative correlation between mNSS and plasticity measured at 14 d after MCAO. Thus, enhanced dendritic plasticity contributes to TMP-elicited functional recovery after ischemic stroke. PMID:26379744

  12. Automating arm movement training following severe stroke: functional exercises with quantitative feedback in a gravity-reduced environment.

    PubMed

    Sanchez, Robert J; Liu, Jiayin; Rao, Sandhya; Shah, Punit; Smith, Robert; Rahman, Tariq; Cramer, Steven C; Bobrow, James E; Reinkensmeyer, David J

    2006-09-01

    An important goal in rehabilitation engineering is to develop technology that allows individuals with severe motor impairment to practice arm movement without continuous supervision from a rehabilitation therapist. This paper describes the development of such a system, called Therapy WREX or ("T-WREX"). The system consists of an orthosis that assists in arm movement across a large workspace, a grip sensor that detects hand grip pressure, and software that simulates functional activities. The arm orthosis is an instrumented, adult-sized version of the Wilmington Robotic Exoskeleton (WREX), which is a five degrees-of-freedom mechanism that passively counterbalances the weight of the arm using elastic bands. After providing a detailed design description of T-WREX, this paper describes two pilot studies of the system's capabilities. The first study demonstrated that individuals with chronic stroke whose arm function is compromised in a normal gravity environment can perform reaching and drawing movements while using T-WREX. The second study demonstrated that exercising the affected arm of five people with chronic stroke with T-WREX over an eight week period improved unassisted movement ability (mean change in Fugl-Meyer score was 5 points +/- 2 SD; mean change in range of motion of reaching was 10%, p < 0.001). These results demonstrate the feasibility of automating upper-extremity rehabilitation therapy for people with severe stroke using passive gravity assistance, a grip sensor, and simple virtual reality software.

  13. In Vivo Inhibition of miR-155 Promotes Recovery after Experimental Mouse Stroke

    PubMed Central

    Caballero-Garrido, Ernesto; Pena-Philippides, Juan Carlos; Lordkipanidze, Tamar; Bragin, Denis; Yang, Yirong; Erhardt, Erik Barry

    2015-01-01

    A multifunctional microRNA, miR-155, has been recently recognized as an important modulator of numerous biological processes. In our previous in vitro studies, miR-155 was identified as a potential regulator of the endothelial morphogenesis. The present study demonstrates that in vivo inhibition of miR-155 supports cerebral vasculature after experimental stroke. Intravenous injections of a specific miR-155 inhibitor were initiated at 48 h after mouse distal middle cerebral artery occlusion (dMCAO). Microvasculature in peri-infarct area, infarct size, and animal functional recovery were assessed at 1, 2, and 3 weeks after dMCAO. Using in vivo two-photon microscopy, we detected improved blood flow and microvascular integrity in the peri-infarct area of miR-155 inhibitor-injected mice. Electron microscopy revealed that, in contrast to the control group, these animals demonstrated well preserved capillary tight junctions (TJs). Western blot analysis data indicate that improved TJ integrity in the inhibitor-injected animals could be associated with stabilization of the TJ protein ZO-1 and mediated by the miR-155 target protein Rheb. MRI analysis showed significant (34%) reduction of infarct size in miR-155 inhibitor-injected animals at 21 d after dMCAO. Reduced brain injury was confirmed by electron microscopy demonstrating decreased neuronal damage in the peri-infarct area of stroke. Preservation of brain tissue was reflected in efficient functional recovery of inhibitor-injected animals. Based on our findings, we propose that in vivo miR-155 inhibition after ischemia supports brain microvasculature, reduces brain tissue damage, and improves the animal functional recovery. SIGNIFICANCE STATEMENT In the present study, we investigated an effect of the in vivo inhibition of a microRNA, miR-155, on brain recovery after experimental cerebral ischemia. To our knowledge, this is the first report describing the efficiency of intravenous anti-miRNA injections in a mouse model

  14. A discussion of the several types of two-stroke-cycle engines

    NASA Technical Reports Server (NTRS)

    Venediger, Herbert J

    1935-01-01

    This report discusses different types of two-stroke engines as well as the three most important design factors: volume of scavenge and charge delivery, scavenging process (scavenging result), and result of charge. Some of the types of engines discussed include: single cylinder with crank-chamber scavenge pump and auxiliary suction piston linked to working connecting rod; and two cylinder engines with a rotary scavenge pump arrangement. Three and four cylinder engines are also discussed in various designs.

  15. Human Urinary Kallidinogenase Promotes Angiogenesis and Cerebral Perfusion in Experimental Stroke

    PubMed Central

    Chen, Yanting; Zhang, Meijuan; Qian, Lai; Chen, Yan; Wu, Zhengzheng; Xu, Yun; Li, Jingwei

    2015-01-01

    Angiogenesisis a key restorative mechanism in response to ischemia, and pro-angiogenic therapy could be beneficial in stroke. Accumulating experimental and clinical evidence suggest that human urinary kallidinogenase (HUK) improves stroke outcome, but the underlying mechanisms are not clear. The aim of current study was to verify roles of HUK in post-ischemic angiogenesis and identify relevant mediators. In rat middle cerebral artery occlusion (MCAO) model, we confirmed that HUK treatment could improve stroke outcome, indicated by reduced infarct size and improved neurological function. Notably, the 18F-FDG micro-PET scan indicated that HUK enhanced cerebral perfusion in rats after MCAO treatment. In addition, HUK promotespost-ischemic angiogenesis, with increased vessel density as well as up-regulated VEGF andapelin/APJ expression in HUK-treated MCAO mice. In endothelial cell cultures, induction of VEGF and apelin/APJ expression, and ERK1/2 phosphorylation by HUK was further confirmed. These changes were abrogated by U0126, a selective ERK1/2 inhibitor. Moreover, F13A, a competitive antagonist of APJ receptor, significantly suppressed HUK-induced VEGF expression. Furthermore, angiogenic functions of HUK were inhibited in the presence of selective bradykinin B1 or B2 receptor antagonist both in vitro and in vivo. Our findings indicate that HUK treatment promotes post-ischemic angiogenesis and cerebral perfusion via activation of bradykinin B1 and B2 receptors, which is potentially due to enhancement expression of VEGF and apelin/APJ in ERK1/2 dependent way. PMID:26222055

  16. Dopamine receptor activation increases glial cell line-derived neurotrophic factor in experimental stroke.

    PubMed

    Kuric, Enida; Wieloch, Tadeusz; Ruscher, Karsten

    2013-09-01

    Treatment with levodopa enhances functional recovery after experimental stroke but its mechanisms of action are elusive. Reactive astrocytes in the ischemic hemisphere are involved in mechanisms promoting recovery and also express dopamine 1 (D1) and dopamine 2 (D2) receptors. Here we investigated if the activation of astrocytic dopamine receptors (D1 and D2) regulates the expression of glial cell line-derived neurotrophic factor (GDNF) after combined in vitro hypoxia/aglycemia (H/A) and studied the expression of GDNF in the ischemic brain after treatment with levodopa/benserazide following transient occlusion of the middle cerebral artery (tMCAO) in the rat. Twenty-four hours after H/A, GDNF levels were upregulated in exposed astrocytes compared to normoxic control cultures and further elevated by the addition of the selective D1 receptor agonist (R)-(+)-SKF-38393 hydrochloride while D1 receptor antagonism by R(+)-SCH-23390 hydrochloride significantly reduced GDNF. No effect on GDNF levels was observed by the application of the D2 receptor agonist R(-)-2,10,11-trihydroxy-N-propyl-noraporphine hydrobromide hydrate or S-(-)-eticlopride hydrochloride (D2 receptor antagonist). After tMCAO, GDNF was upregulated in D1 expressing reactive astrocytes in the peri-infarct area. In addition, treatment with levodopa/benserazide significantly increased GDNF levels in the infarct core and peri-infarct area after tMCAO without affecting the expression of glial fibrillar acidic protein (GFAP), an intermediate filament and marker of reactive gliosis. After stroke, GDNF levels increase in the ischemic hemisphere in rats treated with levodopa, implicating GDNF in the mechanisms of tissue reorganization and plasticity and in l-DOPA enhanced recovery of lost brain function. Our results support levodopa treatment as a potential recovery enhancing therapy in stroke patients.

  17. Cannabinoids in experimental stroke: a systematic review and meta-analysis

    PubMed Central

    England, Timothy J; Hind, William H; Rasid, Nadiah A; O'Sullivan, Saoirse E

    2015-01-01

    Cannabinoids (CBs) show promise as neuroprotectants with some agents already licensed in humans for other conditions. We systematically reviewed CBs in preclinical stroke to guide further experimental protocols. We selected controlled studies assessing acute administration of CBs for experimental stroke, identified through systematic searches. Data were extracted on lesion volume, outcome and quality, and analyzed using random effect models. Results are expressed as standardized mean difference (SMD) with 95% confidence intervals (CIs). In all, 144 experiments (34 publications) assessed CBs on infarct volume in 1,473 animals. Cannabinoids reduced infarct volume in transient (SMD −1.41 (95% CI −1.71), −1.11) P<0.00001) and permanent (−1.67 (−2.08, −1.27), P<0.00001) ischemia and in all subclasses: endocannabinoids (−1.72 (−2.62, −0.82), P=0.0002), CB1/CB2 ligands (−1.75 (−2.19, −1.31), P<0.00001), CB2 ligands (−1.65 (−2.09, −1.22), P<0.00001), cannabidiol (−1.20 (−1.63, −0.77), P<0.00001), Δ9-tetrahydrocannabinol (−1.43 (−2.01, −0.86), P<0.00001), and HU-211 (−2.90 (−4.24, −1.56), P<0.0001). Early and late neuroscores significantly improved with CB use (−1.27 (−1.58, −0.95), P<0.00001; −1.63 (−2.64, −0.62), P<0.002 respectively) and there was no effect on survival. Statistical heterogeneity and publication bias was present, median study quality was 4 (range 1 to 6/8). Overall, CBs significantly reduced infarct volume and improve functional outcome in experimental stroke. Further studies in aged, female and larger animals, with other co-morbidities are required. PMID:25492113

  18. Post-stroke depression therapy: where are we now?

    PubMed

    Nabavi, Seyed Fazel; Turner, Alyna; Dean, Olivia; Sureda, Antoni; Mohammad, Seyed

    2014-01-01

    Post-stroke depression is an important psychological consequence of ischemic stroke, and affects around one third of stroke patients at any time post-stroke. It has a negative impact on patient morbidity and mortality, and as such development of effective post-stroke recognition and treatment strategies are very important. There are several therapeutic strategies for post-stroke depression, including both pharmacological and non-pharmacological approaches. In this review, we present evidence regarding the underlying biology of post-stroke depression, commonalities between post-stroke depression and Major Depressive Disorder and explore several treatment approaches, including antidepressant therapy, psychotherapy, surgical therapy, electroconvulsive therapy, acupuncture, music therapy and natural products. Further experimental and clinical studies are required, particularly in emerging fields such as the role of nutraceuticals in the treatment of stroke.

  19. Glibenclamide enhances the effects of delayed hypothermia after experimental stroke in rats.

    PubMed

    Wu, Zhou; Zhu, Shu-Zhen; Hu, Ya-Fang; Gu, Yong; Wang, Sheng-Nan; Lin, Zhen-Zhou; Xie, Zuo-Shan; Pan, Su-Yue

    2016-07-15

    In order to evaluate whether glibenclamide can extend the therapeutic window during which induced hypothermia can protect against stroke, we subjected adult male Sprague-Dawley rats to middle cerebral artery occlusion (MCAO). We first verified the protective effects of hypothermia induced at 0, 2, 4 or 6h after MCAO onset, and then we assessed the effects of the combination of glibenclamide and hypothermia at 6, 8 or 10h after MCAO onset. At 24h after MCAO, we assessed brain edema, infarct volume, modified neurological severity score, Evans Blue leakage and expression of Sulfonylurea receptor 1 (SUR1) protein and pro-inflammatory factors. No protective effects were observed when hypothermia was induced too long after MCAO. At 6h after MCAO onset, hypothermia alone failed to decrease cerebral edema and infarct volume, but the combination of glibenclamide and hypothermia decreased both. The combination also improved neurological outcome, ameliorated blood-brain barrier damage and decreased levels of COX-2, TNF-α and IL-1β. These results suggest that glibenclamide enhances and extends the therapeutic effects of delayed hypothermia against ischemia stroke, potentially by ameliorating blood-brain barrier damage and declining levels of pro-inflammatory factors. PMID:27134036

  20. [The effect of nitrates on the outcome of acute experimental ischemic stroke].

    PubMed

    Kuzenkov, V S; Krushinskiĭ, A L; Reutov, V P

    2012-01-01

    Effects of nitrates NaNO(3), KNO(3), Mg(NO(3)) 2 on animals (Wistar rats) were studied on the basis of the experimental model of ischemic stroke induced by the occlusion of two carotid arteries. The animals were divided into two groups: the main group (n=60) and the control group (n=30). Three series of experiments were conducted. In each experiment, the rats of the main group were treated with one of nitrates and the control group was treated with physiological solution. It has been shown that nitrates exert either positive or negative effect depending on the cation type, nitrate concentration and the duration of their action on the dynamics of neurologic disturbances. Conditions of the development of neuroprotective effect of nitrates are discussed.

  1. Autophagy Activation by Rapamycin Reduces Severity of Experimental Osteoarthritis

    PubMed Central

    Caramés, Beatriz; Hasegawa, Akihiko; Taniguchi, Noboru; Miyaki, Shigeru; Blanco, Francisco J.; Lotz, Martin

    2012-01-01

    Objectives Osteoarthritis (OA) is associated with cell death and extracellular matrix degradation in articular cartilage. Autophagy is an essential cellular homeostasis mechanism that was found to be deficient in aging and OA cartilage. This study determined whether pharmacological inhibition of the mammalian target of rapamycin (mTOR), a key inhibitor of autophagy, has disease-modifying activity in experimental OA. Methods Experimental OA was induced by transection of the medial meniscotibial ligament and the medial collateral ligament in 2-month old C57Bl/6 mice (n=36). Rapamycin (1 mg/kg weight/day) (n=18 mice) or DMSO vehicle control (n=18 mice) was administered intraperitoneally for 10 weeks. Histopathological changes in articular cartilage and synovium were examined by using semiquantitative scoring systems. Rapamycin effects on mTOR signaling, autophagy, cartilage homeostasis and inflammation were analyzed by immunohistochemistry and immunofluorescence staining. Results Rapamycin affected the mTOR signaling pathway in mouse knee joints as indicated by inhibition of ribosomal protein S6 phosphorylation, a target of mTOR and activation of LC3, a main marker of autophagy. The severity of cartilage degradation was significantly (P < 0.01) reduced in the rapamycin treated group compared to the control group and this was associated with a significant (P < 0.05) decrease in synovitis. Rapamycin treatment also maintained cartilage cellularity, and decreased ADAMTS-5 and IL-1β expression in articular cartilage. Conclusions These results suggest that rapamycin, at least in part by autophagy activation, reduces the severity of experimental OA. Pharmacological activation of autophagy may be an effective therapeutic approach for OA. PMID:22084394

  2. Reduced severity of ischemic stroke and improvement of mitochondrial function after dietary treatment with the anaplerotic substance triheptanoin.

    PubMed

    Schwarzkopf, T M; Koch, K; Klein, J

    2015-08-01

    Triheptanoin, an oily substance, consists of glycerol bound to three molecules of heptanoic acid, a C7 odd-chain fatty acid. A triheptanoin-rich diet has anaplerotic effects because heptanoate metabolism yields succinate which delivers substrates to the Krebs cycle. While previous studies on the effects of triheptanoin focused on metabolic disorders and epilepsy, we investigated triheptanoin's effect on ischemic stroke. Mice were fed a triheptanoin-enriched diet for 14days; controls received soybean oil. Only mice fed triheptanoin had measurable quantities of odd-numbered fatty acids in the plasma and brain. Transient ischemia was induced in the brain by occlusion of the middle cerebral artery (MCAO) for 60min. One day later, mice were tested for neurological function (chimney, rotarod and corner tests) which was found to be better preserved in the triheptanoin group. Microdialysis demonstrated that the strong, neurotoxic increase of extracellular glutamate, which was observed in the mouse striatum during MCAO, was strongly reduced in triheptanoin-fed mice while glucose levels were not affected. Triheptanoin diet reduced the infarct area in stroked mice by about 40%. In ex vivo-experiments with isolated mitochondria, ischemia was found to cause a reduction of mitochondrial respiratory activity. This reduction was attenuated by triheptanoin diet in complex II and IV. In parallel measurements, ATP levels and mitochondrial membrane potential were reduced in control animals but were preserved in triheptanoin-fed mice. We conclude that triheptanoin-fed mice which sustained an experimental stroke had a significantly improved neurological outcome. This beneficial effect is apparently due to an improvement of mitochondrial function and preservation of the cellular energy state. Our findings identify triheptanoin as a promising new dietary agent for neuroprotection. PMID:25982559

  3. Docosahexaenoic acid complexed to albumin provides neuroprotection after experimental stroke in aged rats.

    PubMed

    Eady, Tiffany N; Khoutorova, Larissa; Obenaus, Andre; Mohd-Yusof, Alena; Bazan, Nicolas G; Belayev, Ludmila

    2014-02-01

    Recently we have shown that docosahexaenoic acid complexed to albumin (DHA-Alb) is neuroprotective after experimental stroke in young rats. The purpose of this study was to determine whether treatment with DHA-Alb would be protective in aged rats after focal cerebral ischemia. Isoflurane/nitrous oxide-anesthetized normothermic (brain temperature 36-36.5°C) Sprague-Dawley aged rats (18-months old) received 2h middle cerebral artery occlusion (MCAo) by poly-l-lysine-coated intraluminal suture. The neurological status was evaluated during occlusion (60min) and on days 1, 2, 3 and 7 after MCAo; a grading scale of 0-12 was employed. DHA (5mg/kg), Alb (0.63g/kg), DHA-Alb (5mg/kg+0.63g/kg) or saline was administered i.v. 3h after onset of stroke (n=8-10 per group). Ex vivo T2-weighted imaging (T2WI) of the brains was conducted on an 11.7T MRI on day 7 and 3D reconstructions were generated. Infarct volumes and number of GFAP (reactive astrocytes), ED-1 (activated microglia/microphages), NeuN (neurons)-positive cells and SMI-71 (positive vessels) were counted in the cortex and striatum at the level of the central lesion. Physiological variables were entirely comparable between groups. Animals treated with DHA-Alb showed significantly improved neurological scores compared to vehicle rats; 33% improvement on day 1; 39% on day 2; 41% on day 3; and 45% on day 7. Total and cortical lesion volumes computed from T2WI were significantly reduced by DHA-Alb treatment (62 and 69%, respectively). In addition, treatment with DHA-Alb reduced cortical and total brain infarction while promoting cell survival. We conclude that DHA-Alb therapy is highly neuroprotective in aged rats following focal cerebral ischemia and has potential for the effective treatment of ischemic stroke in aged individuals. PMID:24063996

  4. Combination therapy with normobaric oxygen (NBO) plus thrombolysis in experimental ischemic stroke

    PubMed Central

    Fujiwara, Norio; Murata, Yoshihiro; Arai, Ken; Egi, Yasuhiro; Lu, Jie; Wu, Ona; Singhal, Aneesh B; Lo, Eng H

    2009-01-01

    Background The widespread use of tissue plasminogen activator (tPA), the only FDA-approved acute stroke treatment, remains limited by its narrow therapeutic time window and related risks of brain hemorrhage. Normobaric oxygen therapy (NBO) may be a useful physiological strategy that slows down the process of cerebral infarction, thus potentially allowing for delayed or more effective thrombolysis. In this study we investigated the effects of NBO started simultaneously with intravenous tPA, in spontaneously hypertensive rats subjected to embolic middle cerebral artery (MCA) stroke. After homologous clot injection, animals were randomized into different treatment groups: saline injected at 1 hour; tPA at 1 hour; saline at 1 hour plus NBO; tPA at 1 hour plus NBO. NBO was maintained for 3 hours. Infarct volume, brain swelling and hemorrhagic transformation were quantified at 24 hours. Outcome assessments were blinded to therapy. Results Upon clot injection, cerebral perfusion in the MCA territory dropped below 20% of pre-ischemic baselines. Both tPA-treated groups showed effective thrombolysis (perfusion restored to nearly 100%) and smaller infarct volumes (379 ± 57 mm3 saline controls; 309 ± 58 mm3 NBO; 201 ± 78 mm3 tPA; 138 ± 30 mm3 tPA plus NBO), showing that tPA-induced reperfusion salvages ischemic tissue and that NBO does not significantly alter this neuroprotective effect. NBO had no significant effect on hemorrhagic conversion, brain swelling, or mortality. Conclusion NBO can be safely co-administered with tPA. The efficacy of tPA thrombolysis is not affected and there is no induction of brain hemorrhage or edema. These experimental results require clinical confirmation. PMID:19604385

  5. Detrimental role of the EP1 prostanoid receptor in blood-brain barrier damage following experimental ischemic stroke

    PubMed Central

    Frankowski, Jan C.; DeMars, Kelly M.; Ahmad, Abdullah S.; Hawkins, Kimberly E.; Yang, Changjun; Leclerc, Jenna L.; Doré, Sylvain; Candelario-Jalil, Eduardo

    2015-01-01

    Cyclooxygenase-2 (COX-2) is activated in response to ischemia and significantly contributes to the neuroinflammatory process. Accumulation of COX-2-derived prostaglandin E2 (PGE2) parallels the substantial increase in stroke-mediated blood-brain barrier (BBB) breakdown. Disruption of the BBB is a serious consequence of ischemic stroke, and is mainly mediated by matrix metalloproteinases (MMPs). This study aimed to investigate the role of PGE2 EP1 receptor in neurovascular injury in stroke. We hypothesized that pharmacological blockade or genetic deletion of EP1 protects against BBB damage and hemorrhagic transformation by decreasing the levels and activity of MMP-3 and MMP-9. We found that post-ischemic treatment with the EP1 antagonist, SC-51089, or EP1 genetic deletion results in a significant reduction in BBB disruption and reduced hemorrhagic transformation in an experimental model of transient focal cerebral ischemia. These neurovascular protective effects of EP1 inactivation are associated with a significant reduction in MMP-9/-3, less peripheral neutrophil infiltration, and a preservation of tight junction proteins (ZO-1 and occludin) composing the BBB. Our study identifies the EP1 signaling pathway as an important link between neuroinflammation and MMP-mediated BBB breakdown in ischemic stroke. Targeting the EP1 receptor could represent a novel approach to diminish the devastating consequences of stroke-induced neurovascular damage. PMID:26648273

  6. In vivo and ex vivo magnetic resonance spectroscopy of the infarct and the subventricular zone in experimental stroke

    PubMed Central

    Jiménez-Xarrié, Elena; Davila, Myriam; Gil-Perotín, Sara; Jurado-Rodríguez, Andrés; Candiota, Ana Paula; Delgado-Mederos, Raquel; Lope-Piedrafita, Silvia; García-Verdugo, José Manuel; Arús, Carles; Martí-Fàbregas, Joan

    2015-01-01

    Ex vivo high-resolution magic-angle spinning (HRMAS) provides metabolic information with higher sensitivity and spectral resolution than in vivo magnetic resonance spectroscopy (MRS). Therefore, we used both techniques to better characterize the metabolic pattern of the infarct and the neural progenitor cells (NPCs) in the ipsilateral subventricular zone (SVZi). Ischemic stroke rats were divided into three groups: G0 (non-stroke controls, n=6), G1 (day 1 after stroke, n=6), and G7 (days 6 to 8 after stroke, n=12). All the rats underwent MRS. Three rats per group were analyzed by HRMAS. The remaining rats were used for immunohistochemical studies. In the infarct, both techniques detected significant metabolic changes. The most relevant change was in mobile lipids (2.80 ppm) in the G7 group (a 5.53- and a 3.95-fold increase by MRS and HRMAS, respectively). In the SVZi, MRS did not detect any significant metabolic change. However, HRMAS detected a 2.70-fold increase in lactate and a 0.68-fold decrease in N-acetylaspartate in the G1 group. None of the metabolites correlated with the 1.37-fold increase in NPCs detected by immunohistochemistry in the G7 group. In conclusion, HRMAS improves the metabolic characterization of the brain in experimental ischemic stroke. However, none of the metabolites qualifies as a surrogate biomarker of NPCs. PMID:25605287

  7. Cerebral Hemodynamics and Vascular Reactivity in Mild and Severe Ischemic Rodent Middle Cerebral Artery Occlusion Stroke Models

    PubMed Central

    Sim, Jeongeun; Jo, Areum; Kang, Bok-Man; Lee, Sohee; Bang, Oh Young; Heo, Chaejeong; Jhon, Gil-Ja; Lee, Youngmi

    2016-01-01

    Ischemia can cause decreased cerebral neurovascular coupling, leading to a failure in the autoregulation of cerebral blood flow. This study aims to investigate the effect of varying degrees of ischemia on cerebral hemodynamic reactivity using in vivo real-time optical imaging. We utilized direct cortical stimulation to elicit hyper-excitable neuronal activation, which leads to induced hemodynamic changes in both the normal and middle cerebral artery occlusion (MCAO) ischemic stroke groups. Hemodynamic measurements from optical imaging accurately predict the severity of occlusion in mild and severe MCAO animals. There is neither an increase in cerebral blood volume nor in vessel reactivity in the ipsilateral hemisphere (I.H) of animals with severe MCAO. The pial artery in the contralateral hemisphere (C.H) of the severe MCAO group reacted more slowly than both hemispheres in the normal and mild MCAO groups. In addition, the arterial reactivity of the I.H in the mild MCAO animals was faster than the normal animals. Furthermore, artery reactivity is tightly correlated with histological and behavioral results in the MCAO ischemic group. Thus, in vivo optical imaging may offer a simple and useful tool to assess the degree of ischemia and to understand how cerebral hemodynamics and vascular reactivity are affected by ischemia. PMID:27358581

  8. Progesterone in experimental permanent stroke: a dose-response and therapeutic time-window study

    PubMed Central

    Wali, Bushra; Ishrat, Tauheed; Won, Soonmi; Stein, Donald G.

    2014-01-01

    Currently, the only approved treatment for ischaemic stroke is tissue plasminogen activator, a clot-buster. This treatment can have dangerous consequences if not given within the first 4 h after stroke. Our group and others have shown progesterone to be beneficial in preclinical studies of stroke, but a progesterone dose-response and time-window study is lacking. We tested male Sprague-Dawley rats (12 months old) with permanent middle cerebral artery occlusion or sham operations on multiple measures of sensory, motor and cognitive performance. For the dose-response study, animals received intraperitoneal injections of progesterone (8, 16 or 32 mg/kg) at 1 h post-occlusion, and subcutaneous injections at 6 h and then once every 24 h for 7 days. For the time-window study, the optimal dose of progesterone was given starting at 3, 6 or 24 h post-stroke. Behavioural recovery was evaluated at repeated intervals. Rats were killed at 22 days post-stroke and brains extracted for evaluation of infarct volume. Both 8 and 16 mg/kg doses of progesterone produced attenuation of infarct volume compared with the placebo, and improved functional outcomes up to 3 weeks after stroke on locomotor activity, grip strength, sensory neglect, gait impairment, motor coordination and spatial navigation tests. In the time-window study, the progesterone group exhibited substantial neuroprotection as late as 6 h after stroke onset. Compared with placebo, progesterone showed a significant reduction in infarct size with 3- and 6-h delays. Moderate doses (8 and 16 mg/kg) of progesterone reduced infarct size and improved functional deficits in our clinically relevant model of stroke. The 8 mg/kg dose was optimal in improving motor, sensory and memory function, and this effect was observed over a large therapeutic time window. Progesterone shows promise as a potential therapeutic agent and should be examined for safety and efficacy in a clinical trial for ischaemic stroke. PMID:24374329

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

    PubMed Central

    Zeynalov, Emil; Jones, Susan M.; Seo, Jeong-Woo; Snell, Lawrence D.; Elliott, J. Paul

    2015-01-01

    Background 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. Methods 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. Results 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). Conclusion 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. PMID:26275173

  10. Renin-angiotensin system as a potential therapeutic target in stroke and retinopathy: experimental and clinical evidence.

    PubMed

    Fouda, Abdelrahman Y; Artham, Sandeep; El-Remessy, Azza B; Fagan, Susan C

    2016-02-01

    As our knowledge expands, it is now clear that the renin-angiotensin (Ang) system (RAS) mediates functions other than regulating blood pressure (BP). The RAS plays a central role in the pathophysiology of different neurovascular unit disorders including stroke and retinopathy. Moreover, the beneficial actions of RAS modulation in brain and retina have been documented in experimental research, but not yet exploited clinically. The RAS is a complex system with distinct yet interconnected components. Understanding the different RAS components and their functions under brain and retinal pathological conditions is crucial to reap their benefits. The aim of the present review is to provide an experimental and clinical update on the role of RAS in the pathophysiology and treatment of stroke and retinopathy. Combining the evidence from both these disorders allows a unique opportunity to move both fields forward.

  11. Experimental analysis of precursors to severe problem behavior.

    PubMed

    Fritz, Jennifer N; Iwata, Brian A; Hammond, Jennifer L; Bloom, Sarah E

    2013-01-01

    Some individuals engage in both mild and severe forms of problem behavior. Research has shown that when mild behaviors precede severe behaviors (i.e., the mild behaviors serve as precursors), they can (a) be maintained by the same source of reinforcement as severe behavior and (b) reduce rates of severe behavior observed during assessment. In Study 1, we developed an objective checklist to identify precursors via videotaped trials for 16 subjects who engaged in problem behavior and identified at least 1 precursor for every subject. In Study 2, we conducted separate functional analyses of precursor and severe problem behaviors for 8 subjects, and obtained correspondence between outcomes in 7 cases. In Study 3, we evaluated noncontingent reinforcement schedule thinning plus differential reinforcement of alternative behavior to reduce precursors, increase appropriate behavior, and maintain low rates of severe behavior during 3 treatment analyses for 2 subjects. Results showed that this treatment strategy was effective for behaviors maintained by positive and negative reinforcement.

  12. Charge effect of a liposomal delivery system encapsulating simvastatin to treat experimental ischemic stroke in rats

    PubMed Central

    Campos-Martorell, Mireia; Cano-Sarabia, Mary; Simats, Alba; Hernández-Guillamon, Mar; Rosell, Anna; Maspoch, Daniel; Montaner, Joan

    2016-01-01

    Background and aims Although the beneficial effects of statins on stroke have been widely demonstrated both in experimental studies and in clinical trials, the aim of this study is to prepare and characterize a new liposomal delivery system that encapsulates simvastatin to improve its delivery into the brain. Materials and methods In order to select the optimal liposome lipid composition with the highest capacity to reach the brain, male Wistar rats were submitted to sham or transitory middle cerebral arterial occlusion (MCAOt) surgery and treated (intravenous [IV]) with fluorescent-labeled liposomes with different net surface charges. Ninety minutes after the administration of liposomes, the brain, blood, liver, lungs, spleen, and kidneys were evaluated ex vivo using the Xenogen IVIS® Spectrum imaging system to detect the load of fluorescent liposomes. In a second substudy, simvastatin was assessed upon reaching the brain, comparing free and encapsulated simvastatin (IV) administration. For this purpose, simvastatin levels in brain homogenates from sham or MCAOt rats at 2 hours or 4 hours after receiving the treatment were detected through ultra-high-protein liquid chromatography. Results Whereas positively charged liposomes were not detected in brain or plasma 90 minutes after their administration, neutral and negatively charged liposomes were able to reach the brain and accumulate specifically in the infarcted area. Moreover, neutral liposomes exhibited higher bioavailability in plasma 4 hours after being administered. The detection of simvastatin by ultra-high-protein liquid chromatography confirmed its ability to cross the blood–brain barrier, when administered either as a free drug or encapsulated into liposomes. Conclusion This study confirms that liposome charge is critical to promote its accumulation in the brain infarct after MCAOt. Furthermore, simvastatin can be delivered after being encapsulated. Thus, simvastatin encapsulation might be a promising

  13. Accessing Inpatient Rehabilitation after Acute Severe Stroke: Age, Mobility, Prestroke Function and Hospital Unit Are Associated with Discharge to Inpatient Rehabilitation

    ERIC Educational Resources Information Center

    Hakkennes, Sharon; Hill, Keith D.; Brock, Kim; Bernhardt, Julie; Churilov, Leonid

    2012-01-01

    The objective of this study was to identify the variables associated with discharge to inpatient rehabilitation following acute severe stroke and to determine whether hospital unit contributed to access. Five acute hospitals in Victoria, Australia participated in this study. Patients were eligible for inclusion if they had suffered an acute severe…

  14. Acute stroke after intravitreal bevacizumab to treat choroidal neovascularization due to angioid streaks in pseudoxanthoma elasticum : a severe systemic adverse event after an off-label procedure.

    PubMed

    Besozzi, Gianluca; Ferrara, Andrea; Epifani, Enrico; Intini, Daniela; Apruzzese, Margherita; Provenzano, Antonio; Vetrugno, Michele

    2013-04-01

    To report the occurrence of acute stroke after intravitreal bevacizumab administration to treat choroidal neovascularization due to angioid streaks in a patient affected by pseudoxanthoma elasticum. A 54-year-old man with pseudoxanthoma elasticum had vision loss because of choroidal neovascularization due to angioid streaks. He underwent two intravitreal bevacizumab injections. Three days after the second procedure the patient was afflicted by acute stroke. Intravitreal injection of bevacizumab to treat choroidal neovascularization due to angioid streaks in pseudoxanthoma elasticum could lead to severe systemic adverse events. PMID:23065017

  15. Acupuncture for neurogenesis in experimental ischemic stroke: a systematic review and meta-analysis

    PubMed Central

    Lu, Lin; Zhang, Xiao-guang; Zhong, Linda L.D.; Chen, Zi-xian; Li, Yan; Zheng, Guo-qing; Bian, Zhao-xiang

    2016-01-01

    Acupuncture has been used for patients with stroke and post-stroke rehabilitation for thousands of years. Previous studies reported that acupuncture enhanced stroke recovery through neurogenesis. Hence, we conducted a systematic review and meta-analysis for preclinical studies to assess the current evidence for acupuncture effect on neurogenesis in treating ischaemic stroke. Studies were obtained from six databases, including PubMed, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure, VIP information database, and Chinese Biomedical Literature Database, Ultimately, 34 studies containing 1617 animals were identified. Neurogenesis markers of Brdu, Nestin, PSA-NCAM, NeuN and GFAP were selected as major outcomes. The pooled results of 15 studies marked with Brdu showed significant effects of acupuncture for improving proliferation when compared with control groups (P < 0.01); 13 studies marked with Nestin showed significant effects of acupuncture for increasing proliferation when compared with control groups (P < 0.01); 4 studies marked with PSA-NCAM showed significant effects of acupuncture for enhancing migration when compared with control groups (P < 0.01); 4 studies marked with NeuN showed significant effects of acupuncture for stimulating differentiation when compared with control groups (P < 0.01). The findings suggest that acupuncture is a prospective therapy targeting neurogenesis for ischemic stroke. PMID:26786869

  16. Therapeutic outcomes of transplantation of amniotic fluid-derived stem cells in experimental ischemic stroke

    PubMed Central

    Tajiri, Naoki; Acosta, Sandra; Portillo-Gonzales, Gabriel S.; Aguirre, Daniela; Reyes, Stephanny; Lozano, Diego; Pabon, Mibel; Dela Peña, Ike; Ji, Xunming; Yasuhara, Takao; Date, Isao; Solomita, Marianna A.; Antonucci, Ivana; Stuppia, Liborio; Kaneko, Yuji; Borlongan, Cesar V.

    2014-01-01

    Accumulating preclinical evidence suggests the use of amnion as a source of stem cells for investigations of basic science concepts related to developmental cell biology, but also for stem cells’ therapeutic applications in treating human disorders. We previously reported isolation of viable rat amniotic fluid-derived stem (AFS) cells. Subsequently, we recently reported the therapeutic benefits of intravenous transplantation of AFS cells in a rodent model of ischemic stroke. Parallel lines of investigations have provided safety and efficacy of stem cell therapy for treating stroke and other neurological disorders. This review article highlights the need for investigations of mechanisms underlying AFS cells’ therapeutic benefits and discusses lab-to-clinic translational gating items in an effort to optimize the clinical application of the cell transplantation for stroke. PMID:25165432

  17. Noninvasive ventilatory correction as an adjunct to an experimental systemic reperfusion therapy in acute ischemic stroke.

    PubMed

    Barlinn, Kristian; Balucani, Clotilde; Palazzo, Paola; Zhao, Limin; Sisson, April; Alexandrov, Andrei V

    2010-01-01

    Background. Obstructive sleep apnea (OSA) is a common condition in patients with acute ischemic stroke and associated with early clinical deterioration and poor functional outcome. However, noninvasive ventilatory correction is hardly considered as a complementary treatment option during the treatment phase of acute ischemic stroke. Summary of Case. A 55-year-old woman with an acute middle cerebral artery (MCA) occlusion received intravenous tissue plasminogen activator (tPA) and enrolled into a thrombolytic research study. During tPA infusion, she became drowsy, developed apnea episodes, desaturated and neurologically deteriorated without recanalization, re-occlusion or intracerebral hemorrhage. Urgent noninvasive ventilatory correction with biphasic positive airway pressure (BiPAP) reversed neurological fluctuation. Her MCA completely recanalized 24 hours later. Conclusions. Noninvasive ventilatory correction should be considered more aggressively as a complementary treatment option in selected acute stroke patients. Early initiation of BiPAP can stabilize cerebral hemodynamics and may unmask the true potential of other therapies. PMID:21052540

  18. Streptococcus pneumoniae capsule determines disease severity in experimental pneumococcal meningitis

    PubMed Central

    Grandgirard, Denis; Valente, Luca G.; Täuber, Martin G.; Leib, Stephen L.

    2016-01-01

    Streptococcus pneumoniae bacteria can be characterized into over 90 serotypes according to the composition of their polysaccharide capsules. Some serotypes are common in nasopharyngeal carriage whereas others are associated with invasive disease, but when carriage serotypes do invade disease is often particularly severe. It is unknown whether disease severity is due directly to the capsule type or to other virulence factors. Here, we used a clinical pneumococcal isolate and its capsule-switch mutants to determine the effect of capsule, in isolation from the genetic background, on severity of meningitis in an infant rat model. We found that possession of a capsule was essential for causing meningitis. Serotype 6B caused significantly more mortality than 7F and this correlated with increased capsule thickness in the cerebrospinal fluid (CSF), a stronger inflammatory cytokine response in the CSF and ultimately more cortical brain damage. We conclude that capsule type has a direct effect on meningitis severity. This is an important consideration in the current era of vaccination targeting a subset of capsule types that causes serotype replacement. PMID:27009189

  19. Critical role of sphingosine-1-phosphate receptor-2 in the disruption of cerebrovascular integrity in experimental stroke

    PubMed Central

    Kim, Gab Seok; Yang, Li; Zhang, Guoqi; Zhao, Honggang; Selim, Magdy; McCullough, Louise D.; Kluk, Michael J.; Sanchez, Teresa

    2015-01-01

    The use and effectiveness of current stroke reperfusion therapies are limited by the complications of reperfusion injury, which include increased cerebrovascular permeability and haemorrhagic transformation. Sphingosine-1-phosphate (S1P) is emerging as a potent modulator of vascular integrity via its receptors (S1PR). By using genetic approaches and a S1PR2 antagonist (JTE013), here we show that S1PR2 plays a critical role in the induction of cerebrovascular permeability, development of intracerebral haemorrhage and neurovascular injury in experimental stroke. In addition, inhibition of S1PR2 results in decreased matrix metalloproteinase (MMP)-9 activity in vivo and lower gelatinase activity in cerebral microvessels. S1PR2 immunopositivity is detected only in the ischemic microvessels of wild-type mice and in the cerebrovascular endothelium of human brain autopsy samples. In vitro, S1PR2 potently regulates the responses of the brain endothelium to ischaemic and inflammatory injury. Therapeutic targeting of this novel pathway could have important translational relevance to stroke patients. PMID:26243335

  20. Meta-Analysis and Systematic Review of Neural Stem Cells therapy for experimental ischemia stroke in preclinical studies

    PubMed Central

    Chen, Lukui; Zhang, Guilong; Gu, Yuchun; Guo, Xiaoyuan

    2016-01-01

    To evaluate the preclinical studies using NSCs transplantation therapy for experimental ischemic stroke, and determine the effect size of NSCs therapy and the correlations between different clinical measures. We firstly searched literatures to identify studies of NSCs therapy in animal cerebral ischemia models, and then calculated the quality score of studies, assessed the effect size of NSCs therapy relative to behavioral and histologic endpoints by meta-analysis. A total of 37 studies and 54 independent treated interventions were used for systematic review and meta-analysis. The median quality score was 5 of 10. 36 studies (53 intervention arms) reported functional outcome, 22 studies (34 intervention arms) reported structural outcome. After adjusted by subgroup and sensitivity analysis, the mean effect sizes were improved by 1.35 for mNSS, 1.84 for rotarod test, 0.61 for cylinder test, and 0.84 for infarct volume. Furthermore, effect size had a certain interaction with clinical variables, for example early NSCs therapy etc. In this preclinical studies, we demonstrated that transplanted NSCs significantly improved outcomes (both functional and structural outcome) in ischemic stroke. It is suggested that future preclinical animal model studies of stroke should improve study quality validity and reduce potentially confounded publication bias. PMID:27554433

  1. Isolation and purification of self-renewable human neural stem cells for cell therapy in experimental model of ischemic stroke.

    PubMed

    Azevedo-Pereira, Ricardo L; Daadi, Marcel M

    2013-01-01

    Human embryonic stem cells (hESCs) are pluripotent with a strong self-renewable ability making them a virtually unlimited source of neural cells for structural repair in neurological disorders. Currently, hESCs are one of the most promising cell sources amenable for commercialization of off-shelf cell therapy products. However, along with this strong proliferative capacity of hESCs comes the tumorigenic potential of these cells after transplantation. Thus, the isolation and purification of a homogeneous, population of neural stem cells (hNSCs) are of paramount importance to avoid tumor formation in the host brain. This chapter describes the isolation, neuralization, and long-term perpetuation of hNSCs derived from hESCs through use of specific mitogenic growth factors and the preparation of hNSCs for transplantation in an experimental model of stroke. Additionally, we describe methods to analyze the stroke and size of grafts using magnetic resonance imaging and Osirix software, and neuroanatomical tracing procedures to study axonal remodeling after stroke and cell transplantation.

  2. Propensity of Withania somnifera to Attenuate Behavioural, Biochemical, and Histological Alterations in Experimental Model of Stroke.

    PubMed

    Sood, Abhilasha; Kumar, Aditya; Dhawan, Devinder K; Sandhir, Rajat

    2016-10-01

    The present study was designed to evaluate the beneficial effects of Withania somnifera (WS) pre-supplementation on middle cerebral artery occlusion (MCAO) model of ischemic stroke. Ischemic stroke was induced in the rats by inserting intraluminal suture for 90 min, followed by reperfusion injury for 24 h. The animals were assessed for locomotor functions (by neurological deficit scores, narrow beam walk and rotarod test), cognitive and anxiety-like behavioural functions (by morris water maze and elevated plus maze test). MCAO animals showed significant impairment in locomotor and cognitive functions. Neurobehavioural changes were accompanied by decreased acetylcholinesterase activity, increased oxidative stress in terms of enhanced lipid peroxidation and lowered thiol levels in the MCAO animals. In addition, MCAO animals had cerebral infarcts and the presence of pycnotic nuclei. Single-photon emission computerized tomography (SPECT) of MCAO animals revealed a cerebral infarct as a hypoactive area. On the other hand, pre-supplementation with WS (300 mg/kg body weight) for 30 days to MCAO animals was effective in restoring the acetylcholinesterase activity, lipid peroxidation, thiols and attenuated MCAO induced behavioural deficits. WS significantly reduced the cerebral infarct volume and ameliorated histopathological alterations. Improved blood flow was observed in the SPECT images from the brain regions of ischemic rats pre-treated with WS. The results of the study showed a protective effect of WS supplementation in ischemic stroke and are suggestive of its potential application in stroke management.

  3. Propensity of Withania somnifera to Attenuate Behavioural, Biochemical, and Histological Alterations in Experimental Model of Stroke.

    PubMed

    Sood, Abhilasha; Kumar, Aditya; Dhawan, Devinder K; Sandhir, Rajat

    2016-10-01

    The present study was designed to evaluate the beneficial effects of Withania somnifera (WS) pre-supplementation on middle cerebral artery occlusion (MCAO) model of ischemic stroke. Ischemic stroke was induced in the rats by inserting intraluminal suture for 90 min, followed by reperfusion injury for 24 h. The animals were assessed for locomotor functions (by neurological deficit scores, narrow beam walk and rotarod test), cognitive and anxiety-like behavioural functions (by morris water maze and elevated plus maze test). MCAO animals showed significant impairment in locomotor and cognitive functions. Neurobehavioural changes were accompanied by decreased acetylcholinesterase activity, increased oxidative stress in terms of enhanced lipid peroxidation and lowered thiol levels in the MCAO animals. In addition, MCAO animals had cerebral infarcts and the presence of pycnotic nuclei. Single-photon emission computerized tomography (SPECT) of MCAO animals revealed a cerebral infarct as a hypoactive area. On the other hand, pre-supplementation with WS (300 mg/kg body weight) for 30 days to MCAO animals was effective in restoring the acetylcholinesterase activity, lipid peroxidation, thiols and attenuated MCAO induced behavioural deficits. WS significantly reduced the cerebral infarct volume and ameliorated histopathological alterations. Improved blood flow was observed in the SPECT images from the brain regions of ischemic rats pre-treated with WS. The results of the study showed a protective effect of WS supplementation in ischemic stroke and are suggestive of its potential application in stroke management. PMID:26718711

  4. Neuroprotection by glutamate oxaloacetate transaminase in ischemic stroke: an experimental study.

    PubMed

    Campos, Francisco; Sobrino, Tomás; Ramos-Cabrer, Pedro; Argibay, Bárbara; Agulla, Jesús; Pérez-Mato, María; Rodríguez-González, Raquel; Brea, David; Castillo, José

    2011-06-01

    As ischemic stroke is associated with an excessive release of glutamate into the neuronal extracellular space, a decrease in blood glutamate levels could provide a mechanism to remove it from the brain tissue, by increasing the brain-blood gradient. In this regard, the ability of glutamate oxaloacetate transaminase (GOT) to metabolize glutamate in blood could represent a potential neuroprotective tool for ischemic stroke. This study aimed to determine the neuroprotective effects of GOT in an animal model of cerebral ischemia by means of a middle cerebral arterial occlusion (MCAO) following the Stroke Therapy Academic Industry Roundtable (STAIR) group guidelines. In this animal model, oxaloacetate-mediated GOT activation inhibited the increase of blood and cerebral glutamate after MCAO. This effect is reflected in a reduction of infarct size, smaller edema volume, and lower sensorimotor deficits with respect to controls. Magnetic resonance spectroscopy confirmed that the increase of glutamate levels in the brain parenchyma after MCAO is inhibited after oxaloacetate-mediated GOT activation. These findings show the capacity of the GOT to remove glutamate from the brain by means of blood glutamate degradation, and suggest the applicability of this enzyme as an efficient and novel neuroprotective tool against ischemic stroke.

  5. Barrier mechanisms in neonatal stroke

    PubMed Central

    Kratzer, Ingrid; Chip, Sophorn; Vexler, Zinaida S.

    2014-01-01

    Clinical data continue to reveal that the incidence of perinatal stroke is high, similar to that in the elderly. Perinatal stroke leads to significant morbidity and severe long-term neurological and cognitive deficits, including cerebral palsy. Experimental models of cerebral ischemia in neonatal rodents have shown that the pathophysiology of perinatal brain damage is multifactorial. Cerebral vasculature undergoes substantial structural and functional changes during early postnatal brain development. Thus, the state of the vasculature could affect susceptibility of the neonatal brain to cerebral ischemia. In this review, we discuss some of the most recent findings regarding the neurovascular responses of the immature brain to focal arterial stroke in relation to neuroinflammation. We also discuss a possible role of the neonatal blood-CSF barrier in modulating inflammation and the long-term effects of early neurovascular integrity after neonatal stroke on angiogenesis and neurogenesis. PMID:25426016

  6. Effects of minocycline on endogenous neural stem cells after experimental stroke.

    PubMed

    Rueger, M A; Muesken, S; Walberer, M; Jantzen, S U; Schnakenburg, K; Backes, H; Graf, R; Neumaier, B; Hoehn, M; Fink, G R; Schroeter, M

    2012-07-26

    Minocycline has been reported to reduce infarct size after focal cerebral ischemia, due to an attenuation of microglia activation and prevention of secondary damage from stroke-induced neuroinflammation. We here investigated the effects of minocycline on endogenous neural stem cells (NSCs) in vitro and in a rat stroke model. Primary cultures of fetal rat NSCs were exposed to minocycline to characterize its effects on cell survival and proliferation. To assess these effects in vivo, permanent cerebral ischemia was induced in adult rats, treated systemically with minocycline or placebo. Imaging 7 days after ischemia comprised (i) Magnetic Resonance Imaging (MRI), assessing the extent of infarcts, (ii) Positron Emission Tomography (PET) with [(11)C]PK11195, characterizing neuroinflammation, and (iii) PET with 3'-deoxy-3'-[(18)F]fluoro-L-thymidine ([(18)F]FLT), detecting proliferating endogenous NSCs. Immunohistochemistry was used to verify ischemic damage and characterize cellular inflammatory and repair processes in more detail. In vitro, specific concentrations of minocycline significantly increased NSC numbers without increasing their proliferation, indicating a positive effect of minocycline on NSC survival. In vivo, endogenous NSC activation in the subventricular zone (SVZ) measured by [(18)F]FLT PET correlated well with infarct volumes. Similar to in vitro findings, minocycline led to a specific increase in endogenous NSC activity in both the SVZ as well as the hippocampus. [(11)C]PK11195 PET detected neuroinflammation in the infarct core as well as in peri-infarct regions, with both its extent and location independent of the infarct size. The data did not reveal an effect of minocycline on stroke-induced neuroinflammation. We show that multimodal PET imaging can be used to characterize and quantify complex cellular processes occurring after stroke, as well as their modulation by therapeutic agents. We found minocycline, previously implied in attenuating

  7. Experimentally determined aeroacoustic performance and control of several sonic inlets

    NASA Technical Reports Server (NTRS)

    Miller, B. A.

    1975-01-01

    Low speed wind tunnel tests were conducted to determine the aeroacoustic performance of several model sonic inlets. The results were analyzed to indicate how inlet aeroacoustic characteristics were affected by inlet design and operating conditions. A system for regulating sonic inlet noise reduction was developed and tested. Results indicate that pressure losses at forward velocity may be substantially less than those at static conditions. This is particularly true for translating centerbody inlets with the centerbody extended in the approach and landing position. Operation to simulated takeoff incidence angles of 50 degrees was demonstrated with good inlet performance. Inlet sound pressure level reduction was regulation was regulated to within approximately + or - 1 dB by controlling inlet surface static pressure measured at the diffuser exit.

  8. Accessing inpatient rehabilitation after acute severe stroke: age, mobility, prestroke function and hospital unit are associated with discharge to inpatient rehabilitation.

    PubMed

    Hakkennes, Sharon; Hill, Keith D; Brock, Kim; Bernhardt, Julie; Churilov, Leonid

    2012-12-01

    The objective of this study was to identify the variables associated with discharge to inpatient rehabilitation following acute severe stroke and to determine whether hospital unit contributed to access. Five acute hospitals in Victoria, Australia participated in this study. Patients were eligible for inclusion if they had suffered an acute severe stroke (Mobility Scale for Acute Stroke ≤ 15). Physiotherapists assessed patients on day 3 poststroke, collecting demographic information and information relating to their prestroke status, social status and current status. Stepwise logistic-regression modelling was used to examine the association between age, type of stroke, prestroke living situation, comorbidities, availability of carer on discharge, current mobility, bladder continence, bowel continence, cognition and communication and the dependent variable, discharge destination (rehabilitation/other). The resulting model was analysed using hierarchical logistic regression with hospital unit as the clustering variable. Of the 108 patients fulfilling the inclusion criteria, 70 (64.8%) were discharged to rehabilitation. The variables independently associated with discharge to rehabilitation were younger age [odds ratio (OR)=0.89, 95% confidence interval (CI)=0.83-0.95, P=0.001], independent premorbid functional status (OR=14.92, 95% CI=2.43-91.60, P=0.004) and higher level of current mobility (OR=1.31, 95% CI=1.02-1.66, P<0.03). The multilevel model estimated that 12% of the total variability in discharge destination was explained by differences between the hospital units (ρ=0.12, 95% CI=0.02-0.55, P=0.048). The results indicate that the variables associated with discharge to rehabilitation following severe stroke are younger age, independent prestroke functional status and higher level of current mobility. In addition, organizational factors play a role in selection for rehabilitation, suggesting inequity in access for this patient group. PMID:22728683

  9. In Vivo Non-Invasive Tracking of Macrophage Recruitment to Experimental Stroke.

    PubMed

    Selt, Marion; Tennstaedt, Annette; Beyrau, Andreas; Nelles, Melanie; Schneider, Gabriele; Löwik, Clemens; Hoehn, Mathias

    2016-01-01

    Brain-infiltrating monocyte-derived macrophages are one of the key players in the local immune response after stroke. It is now widely accepted that the inflammatory response is not an exclusively destructive process. However, the underlying molecular mechanisms needed for proper regulation still remain to be elucidated. Here, we propose an in vitro labelling strategy for multimodal in vivo observation of macrophage dynamics distinguished from brain-residing microglia response. Prior to intracerebral transplantation into the striatum of recipient mice or systemic administration, monocytes and macrophages, isolated from luciferase-expressing mice, were labelled with superparamagnetic iron oxide particles. Temporo-spatial localization was monitored by magnetic resonance imaging, whereas survival of grafted cells was investigated using bioluminescence imaging. The labelling procedure of the isolated cells did not significantly influence cell characteristics and resulted in detection of as few as 500 labelled cells in vivo. Two weeks after stereotactic transplantation, the luciferase signal was sustained traceable, with approximately 18% of the original luciferase signal detectable for monocytes and about 30% for macrophages. Hypointensity in MRI of the graft appeared unaltered in spatial location. In a therapeutically relevant approach, systemic cell administration after stroke resulted in accumulation mostly in thoracic regions, as could be visualized with BLI. For detection of homing to ischemic brain tissue more cells need to be administered. Nevertheless, during parallel MRI sessions recruitment of i.v. injected cells to the lesion site could be detected by day 2 post stroke as scattered hypointense signal voids. With further increase in sensitivity, our multi-facetted labelling strategy will provide the basis for in vivo tracking and fate specification of tissue-infiltrating macrophages and their distinct role in stroke-related neuro-inflammation. PMID:27341631

  10. In Vivo Non-Invasive Tracking of Macrophage Recruitment to Experimental Stroke

    PubMed Central

    Selt, Marion; Tennstaedt, Annette; Beyrau, Andreas; Nelles, Melanie; Schneider, Gabriele; Löwik, Clemens; Hoehn, Mathias

    2016-01-01

    Brain-infiltrating monocyte-derived macrophages are one of the key players in the local immune response after stroke. It is now widely accepted that the inflammatory response is not an exclusively destructive process. However, the underlying molecular mechanisms needed for proper regulation still remain to be elucidated. Here, we propose an in vitro labelling strategy for multimodal in vivo observation of macrophage dynamics distinguished from brain-residing microglia response. Prior to intracerebral transplantation into the striatum of recipient mice or systemic administration, monocytes and macrophages, isolated from luciferase-expressing mice, were labelled with superparamagnetic iron oxide particles. Temporo-spatial localization was monitored by magnetic resonance imaging, whereas survival of grafted cells was investigated using bioluminescence imaging. The labelling procedure of the isolated cells did not significantly influence cell characteristics and resulted in detection of as few as 500 labelled cells in vivo. Two weeks after stereotactic transplantation, the luciferase signal was sustained traceable, with approximately 18% of the original luciferase signal detectable for monocytes and about 30% for macrophages. Hypointensity in MRI of the graft appeared unaltered in spatial location. In a therapeutically relevant approach, systemic cell administration after stroke resulted in accumulation mostly in thoracic regions, as could be visualized with BLI. For detection of homing to ischemic brain tissue more cells need to be administered. Nevertheless, during parallel MRI sessions recruitment of i.v. injected cells to the lesion site could be detected by day 2 post stroke as scattered hypointense signal voids. With further increase in sensitivity, our multi-facetted labelling strategy will provide the basis for in vivo tracking and fate specification of tissue-infiltrating macrophages and their distinct role in stroke-related neuro-inflammation. PMID:27341631

  11. Proper housing conditions in experimental stroke studies-special emphasis on environmental enrichment.

    PubMed

    Mering, Satu; Jolkkonen, Jukka

    2015-01-01

    Environmental enrichment provides laboratory animals with novelty and extra space, allowing different forms of multisensory stimulation ranging from social grouping to enhanced motor activity. At the extreme end of the spectrum, one can have a super-enriched environment. Environmental enrichment is believed to result in improved cognitive and sensorimotor functions both in naïve rodents and in animals with brain lesions such as those occurring after a stroke. Robust behavioral effects in animals which have suffered a stroke are probably related not only to neuronal plasticity in the perilesional cortex but also in remote brain areas. There is emerging evidence to suggest that testing restorative therapies in an enriched environment can maximize treatment effects, e.g., the perilesional milieu seems to be more receptive to concomitant pharmacotherapy and/or cell therapy. This review provides an updated overview on the effect of an enriched environment in stroke animals from the practical points to be considered when planning experiments to the mechanisms explaining why combined therapies can contribute to behavioral improvement in a synergistic manner.

  12. Proper housing conditions in experimental stroke studies—special emphasis on environmental enrichment

    PubMed Central

    Mering, Satu; Jolkkonen, Jukka

    2015-01-01

    Environmental enrichment provides laboratory animals with novelty and extra space, allowing different forms of multisensory stimulation ranging from social grouping to enhanced motor activity. At the extreme end of the spectrum, one can have a super-enriched environment. Environmental enrichment is believed to result in improved cognitive and sensorimotor functions both in naïve rodents and in animals with brain lesions such as those occurring after a stroke. Robust behavioral effects in animals which have suffered a stroke are probably related not only to neuronal plasticity in the perilesional cortex but also in remote brain areas. There is emerging evidence to suggest that testing restorative therapies in an enriched environment can maximize treatment effects, e.g., the perilesional milieu seems to be more receptive to concomitant pharmacotherapy and/or cell therapy. This review provides an updated overview on the effect of an enriched environment in stroke animals from the practical points to be considered when planning experiments to the mechanisms explaining why combined therapies can contribute to behavioral improvement in a synergistic manner. PMID:25870536

  13. Low ficolin-3 levels in early follow-up serum samples are associated with the severity and unfavorable outcome of acute ischemic stroke

    PubMed Central

    2011-01-01

    Background A number of data indicate that the lectin pathway of complement activation contributes to the pathophysiology of ischemic stroke. The lectin pathway may be triggered by the binding of mannose-binding lectin (MBL), ficolin-2 or ficolin-3 to different ligands. Although several papers demonstrated the significance of MBL in ischemic stroke, the role of ficolins has not been examined. Methods Sera were obtained within 12 hours after the onset of ischemic stroke (admission samples) and 3-4 days later (follow-up samples) from 65 patients. The control group comprised 100 healthy individuals and 135 patients with significant carotid stenosis (patient controls). The concentrations of ficolin-2 and ficolin-3, initiator molecules of the lectin complement pathway, were measured by ELISA methods. Concentration of C-reactive protein (CRP) was also determined by a particle-enhanced immunturbidimetric assay. Results Concentrations of both ficolin-2 and ficolin-3 were significantly (p < 0.001) decreased in both the admission and in the follow-up samples of patients with definite ischemic stroke as compared to healthy subjects. Concentrations of ficolin-2 and ficolin-3 were even higher in patient controls than in healthy subjects, indicating that the decreased levels in sera during the acute phase of stroke are related to the acute ischemic event. Ficolin-3 levels in the follow-up samples inversely correlated with the severity of stroke indicated by NIH scale on admission. In follow-up samples an inverse correlation was observed between ficolin-3 levels and concentration of S100β, an indicator of the size of cerebral infarct. Patients with low ficolin-3 levels and high CRP levels in the follow up samples had a significantly worse outcome (adjusted ORs 5.6 and 3.9, respectively) as measured by the modified Rankin scale compared to patients with higher ficolin-3 and lower CRP concentrations. High CRP concentrations were similarly predictive for worse outcome, and the

  14. Role of sleep-disordered breathing and sleep-wake disturbances for stroke and stroke recovery

    PubMed Central

    2016-01-01

    Background: Sleep-disordered breathing (SDB) and sleep-wake disturbances (SWD) are highly prevalent in stroke patients. Recent studies suggest that they represent both a risk factor and a consequence of stroke and affect stroke recovery, outcome, and recurrence. Methods: Review of literature. Results: Several studies have proven SDB to represent an independent risk factor for stroke. Sleep studies in TIA and stroke patients are recommended in view of the very high prevalence (>50%) of SDB (Class IIb, level of evidence B). Treatment of obstructive SDB with continuous positive airway pressure is recommended given the strength of the increasing evidence in support of a positive effect on outcome (Class IIb, level of evidence B). Oxygen, biphasic positive airway pressure, and adaptive servoventilation may be considered in patients with central SDB. Recently, both reduced and increased sleep duration, as well as hypersomnia, insomnia, and restless legs syndrome (RLS), were also suggested to increase stroke risk. Mainly experimental studies found that SWD may in addition impair neuroplasticity processes and functional stroke recovery. Treatment of SWD with hypnotics and sedative antidepressants (insomnia), activating antidepressants or stimulants (hypersomnia), dopaminergic drugs (RLS), and clonazepam (parasomnias) are based on single case observations and should be used with caution. Conclusions: SDB and SWD increase the risk of stroke in the general population and affect short- and long-term stroke recovery and outcome. Current knowledge supports the systematic implementation of clinical procedures for the diagnosis and treatment of poststroke SDB and SWD on stroke units. PMID:27488603

  15. Airplane stroke syndrome.

    PubMed

    Humaidan, Hani; Yassi, Nawaf; Weir, Louise; Davis, Stephen M; Meretoja, Atte

    2016-07-01

    Only 37 cases of stroke during or soon after long-haul flights have been published to our knowledge. In this retrospective observational study, we searched the Royal Melbourne Hospital prospective stroke database and all discharge summaries from 1 September 2003 to 30 September 2014 for flight-related strokes, defined as patients presenting with stroke within 14days of air travel. We hypothesised that a patent foramen ovale (PFO) is an important, but not the only mechanism, of flight-related stroke. We describe the patient, stroke, and flight characteristics. Over the study period, 131 million passengers arrived at Melbourne airport. Our centre admitted 5727 stroke patients, of whom 42 (0.73%) had flight-related strokes. Flight-related stroke patients were younger (median age 65 versus 73, p<0.001), had similar stroke severity, and received intravenous thrombolysis more often than non-flight-related stroke patients. Seven patients had flight-related intracerebral haemorrhage. The aetiology of the ischaemic strokes was cardioembolic in 14/35 (40%), including seven patients with confirmed PFO, one with atrial septal defect, four with atrial fibrillation, one with endocarditis, and one with aortic arch atheroma. Paradoxical embolism was confirmed in six patients. Stroke related to air travel is a rare occurrence, less than one in a million. Although 20% of patients had a PFO, distribution of stroke aetiologies was diverse and was not limited to PFO and paradoxical embolism. PMID:26898578

  16. TTC7B emerges as a novel risk factor for ischemic stroke through the convergence of several genome-wide approaches

    PubMed Central

    Krug, Tiago; Gabriel, João Paulo; Taipa, Ricardo; Fonseca, Benedita V; Domingues-Montanari, Sophie; Fernandez-Cadenas, Israel; Manso, Helena; Gouveia, Liliana O; Sobral, João; Albergaria, Isabel; Gaspar, Gisela; Jiménez-Conde, Jordi; Rabionet, Raquel; Ferro, José M; Montaner, Joan; Vicente, Astrid M; Silva, Mário Rui; Matos, Ilda; Lopes, Gabriela; Oliveira, Sofia A

    2012-01-01

    We hereby propose a novel approach to the identification of ischemic stroke (IS) susceptibility genes that involves converging data from several unbiased genetic and genomic tools. We tested the association between IS and genes differentially expressed between cases and controls, then determined which data mapped to previously reported linkage peaks and were nominally associated with stroke in published genome-wide association studies. We first performed gene expression profiling in peripheral blood mononuclear cells of 20 IS cases and 20 controls. Sixteen differentially expressed genes mapped to reported whole-genome linkage peaks, including the TTC7B gene, which has been associated with major cardiovascular disease. At the TTC7B locus, 46 tagging polymorphisms were tested for association in 565 Portuguese IS cases and 520 controls. Markers nominally associated in at least one test and defining associated haplotypes were then examined in 570 IS Spanish cases and 390 controls. Several polymorphisms and haplotypes in the intron 5–intron 6 region of TTC7B were also associated with IS risk in the Spanish and combined data sets. Multiple independent lines of evidence therefore support the role of TTC7B in stroke susceptibility, but further work is warranted to identify the exact risk variant and its pathogenic potential. PMID:22453632

  17. Multimodal imaging reveals temporal and spatial microglia and matrix metalloproteinase activity after experimental stroke

    PubMed Central

    Zinnhardt, Bastian; Viel, Thomas; Wachsmuth, Lydia; Vrachimis, Alexis; Wagner, Stefan; Breyholz, Hans-Jörg; Faust, Andreas; Hermann, Sven; Kopka, Klaus; Faber, Cornelius; Dollé, Frédéric; Pappata, Sabina; Planas, Anna M; Tavitian, Bertrand; Schäfers, Michael; Sorokin, Lydia M; Kuhlmann, Michael T; Jacobs, Andreas H

    2015-01-01

    Stroke is the most common cause of death and disability from neurologic disease in humans. Activation of microglia and matrix metalloproteinases (MMPs) is involved in positively and negatively affecting stroke outcome. Novel, noninvasive, multimodal imaging methods visualizing microglial and MMP alterations were employed. The spatio-temporal dynamics of these parameters were studied in relation to blood flow changes. Micro positron emission tomography (μPET) using [18F]BR-351 showed MMP activity within the first days after transient middle cerebral artery occlusion (tMCAo), followed by increased [18F]DPA-714 uptake as a marker for microglia activation with a maximum at 14 days after tMCAo. The inflammatory response was spatially located in the infarct core and in adjacent (penumbral) tissue. For the first time, multimodal imaging based on PET, single photon emission computed tomography, and magnetic resonance imaging revealed insight into the spatio-temporal distribution of critical parameters of poststroke inflammation. This allows further evaluation of novel treatment paradigms targeting the postischemic inflammation. PMID:26126867

  18. Timing of cord blood treatment after experimental stroke determines therapeutic efficacy.

    PubMed

    Newcomb, Jennifer D; Ajmo, Craig T; Sanberg, Cyndy D; Sanberg, Paul R; Pennypacker, Keith R; Willing, Alison E

    2006-01-01

    Embolic stroke is thought to cause irreparable damage in the brain immediately adjacent to the region of reduced blood perfusion. Therefore, much of the current research focuses on treatments such as anti-inflammatory, neuroprotective, and cell replacement strategies to minimize behavioral and physiological consequences. In the present study, intravenous delivery of human umbilical cord blood cells (HUCBC) 48 h after a middle cerebral artery occlusion (MCAo) in a rat resulted in both behavioral and physiological recovery. Nissl and TUNEL staining demonstrated that many of the neurons in the core were rescued, indicating that while both necrotic and apoptotic cell death occur in ischemia, it is clear that apoptosis plays a larger role than first anticipated. Further, immunohistochemical and histochemical analysis showed a diminished and/or lack of granulocyte and monocyte infiltration and astrocytic and microglial activation in the parenchyma in animals treated with HUCBC 48 h poststroke. Successful treatment at this time point should offer encouragement to clinicians that a therapy with a broader window of efficacy may soon be available to treat stroke. PMID:16719056

  19. Percutaneous transluminal angioplasty and stenting for severe stenosis of the intracranial extradural internal carotid artery causing transient ischemic attack or minor stroke.

    PubMed

    Ko, Jun Kyeung; Choi, Chang Hwa; Cha, Seung Heon; Choi, Byung Kwan; Cho, Won Ho; Kang, Tae Ho; Sung, Sang Min; Cho, Han Jin; Lee, Tae Hong

    2015-08-01

    The purpose of this study is to assess the technical feasibility and clinical efficacy of percutaneous transluminal angioplasty and stenting (PTAS) for symptomatic stenosis of the intracranial extradural (petrous and cavernous) internal carotid artery (ICA).Review of medical records identified 26 consecutive patients who underwent PTAS using a balloon-expandable coronary stent (n = 15, 57.7%) or a Wingspan self-expandable stent (n = 11, 42.3%) for treatment of severe stenosis (>70%) involving the intracranial extradural ICA. The inclusion criteria were transient ischemic attack with an ABCD(2) score of ≥3 (n = 12, 46.2%) or minor stroke with an NIHSS score of ≤4 (n = 14, 53.8%). Technical success rates, complications, and angiographic and clinical outcomes were analyzed retrospectively.PTAS was technically successful in all patients. The mean stenosis ratio decreased from 77.1% to 10.0% immediately after PTAS. The overall incidence of procedural complications was 23.1%, and the postoperative permanent morbidity/mortality rate was 7.7%. A total of 22 patients were tracked over an average period of 29.9 months. During the observation period, 20 patients (90.9%) had no further cerebrovascular events and stroke recurrence occurred in two patients (9.1%), resulting in an annual stroke risk of 3.7%. Two cases (11.1%) of significant in-stent restenosis (>50%) were found on follow-up angiography (n = 18).PTAS for severe stenosis (>70%) involving the intracranial extradural ICA showed a good technical feasibility and favorable clinical outcome in patients with transient ischemic attack or minor stroke.

  20. Lightning return stroke models

    NASA Technical Reports Server (NTRS)

    Lin, Y. T.; Uman, M. A.; Standler, R. B.

    1980-01-01

    We test the two most commonly used lightning return stroke models, Bruce-Golde and transmission line, against subsequent stroke electric and magnetic field wave forms measured simultaneously at near and distant stations and show that these models are inadequate to describe the experimental data. We then propose a new return stroke model that is physically plausible and that yields good approximations to the measured two-station fields. Using the new model, we derive return stroke charge and current statistics for about 100 subsequent strokes.

  1. Use of a robotic device for the rehabilitation of severe upper limb paresis in subacute stroke: exploration of patient/robot interactions and the motor recovery process.

    PubMed

    Duret, Christophe; Courtial, Ophélie; Grosmaire, Anne-Gaëlle; Hutin, Emilie

    2015-01-01

    This pioneering observational study explored the interaction between subacute stroke inpatients and a rehabilitation robot during upper limb training. 25 stroke survivors (age 55 ± 17 years; time since stroke, 52 ± 21 days) with severe upper limb paresis carried out 16 sessions of robot-assisted shoulder/elbow training (InMotion 2.0, IMT, Inc., MA, USA) combined with standard therapy. The values of 3 patient/robot interaction parameters (a guidance parameter: Stiffness, a velocity-related parameter: Slottime, and Robotic Power) were compared between sessions 1 (S1), 4 (S4), 8 (S8), 12 (S12), and 16 (S16). Pre/post Fugl-Meyer Assessment (FMA) scores were compared in 18 patients. Correlations between interaction parameters and clinical and kinematic outcome measures were evaluated. Slottime decreased at S8 (P = 0.003), while Guidance decreased at S12 (P = 0.008). Robotic Power tended to decrease until S16. FMA scores improved from S1 to S16 (+49%, P = 0.002). Changes in FMA score were correlated with the Stiffness parameter (R = 0.4, P = 0.003). Slottime was correlated with movement velocity. This novel approach demonstrated that a robotic device is a useful and reliable tool for the quantification of interaction parameters. Moreover, changes in these parameters were correlated with clinical and kinematic changes. These results suggested that robot-based recordings can provide new insights into the motor recovery process.

  2. Use of a Robotic Device for the Rehabilitation of Severe Upper Limb Paresis in Subacute Stroke: Exploration of Patient/Robot Interactions and the Motor Recovery Process

    PubMed Central

    Courtial, Ophélie; Grosmaire, Anne-Gaëlle; Hutin, Emilie

    2015-01-01

    This pioneering observational study explored the interaction between subacute stroke inpatients and a rehabilitation robot during upper limb training. 25 stroke survivors (age 55 ± 17 years; time since stroke, 52 ± 21 days) with severe upper limb paresis carried out 16 sessions of robot-assisted shoulder/elbow training (InMotion 2.0, IMT, Inc., MA, USA) combined with standard therapy. The values of 3 patient/robot interaction parameters (a guidance parameter: Stiffness, a velocity-related parameter: Slottime, and Robotic Power) were compared between sessions 1 (S1), 4 (S4), 8 (S8), 12 (S12), and 16 (S16). Pre/post Fugl-Meyer Assessment (FMA) scores were compared in 18 patients. Correlations between interaction parameters and clinical and kinematic outcome measures were evaluated. Slottime decreased at S8 (P = 0.003), while Guidance decreased at S12 (P = 0.008). Robotic Power tended to decrease until S16. FMA scores improved from S1 to S16 (+49%, P = 0.002). Changes in FMA score were correlated with the Stiffness parameter (R = 0.4, P = 0.003). Slottime was correlated with movement velocity. This novel approach demonstrated that a robotic device is a useful and reliable tool for the quantification of interaction parameters. Moreover, changes in these parameters were correlated with clinical and kinematic changes. These results suggested that robot-based recordings can provide new insights into the motor recovery process. PMID:25821804

  3. Pediatric Stroke

    MedlinePlus

    ... Trials News About Neurology Image Library Search The Internet Stroke Center Patients & Families About Stroke Stroke Diagnosis ... UT Southwestern Medical Center. Copyright © 1997-2016 - The Internet Stroke Center. All rights reserved. The information contained ...

  4. Ischemic Stroke

    MedlinePlus

    A stroke is a medical emergency. There are two types - ischemic and hemorrhagic. Ischemic stroke is the most common type. It is usually ... are at risk for having a more serious stroke. Symptoms of stroke are Sudden numbness or weakness ...

  5. Genetic Stroke Syndromes

    PubMed Central

    Barrett, Kevin M.; Meschia, James F.

    2014-01-01

    Purpose of Review: This review describes the clinical and radiographic features, genetic determinants, and treatment options for the most well-characterized monogenic disorders associated with stroke. Recent Findings: Stroke is a phenotype of many clinically important inherited disorders. Recognition of the clinical manifestations of genetic disorders associated with stroke is important for accurate diagnosis and prognosis. Genetic studies have led to the discovery of specific mutations associated with the clinical phenotypes of many inherited stroke syndromes. Summary: Several inherited causes of stroke have established and effective therapies, further underscoring the importance of timely diagnosis. PMID:24699489

  6. Assessing phagocytic clearance of cell death in experimental stroke by ligatable fluorescent probes.

    PubMed

    Minchew, Candace L; Didenko, Vladimir V

    2014-05-27

    We describe a new histochemical approach for visualization of phagocytic clearance in focal brain ischemia. The approach permits the study of elimination of dead cells in stroke by waste-management phagocytes of any cellular lineage. Although numerous cells of different origins that are capable of phagocytosis are present in ischemic brain, only part of them actively engulf and digest cell corpses. The selective visualization, quantification and analysis of such active phagocytic waste-management are helpful in assessing brain response to ischemia. Efficient cell death clearance is important for brain recovery from ischemic injury, as it opens the way for the subsequent regenerative processes. The failure to clean the corpses would result in a toxic reaction caused by non-degraded DNA and proteins. The described procedure uses fluorescent probes selectively ligated by a viral topoisomerase to characteristic DNA breaks produced in all phagocytes during engulfment and digestion of cells irreversibly damaged by ischemia. The method is a new tool for the investigation of brain reaction to ischemic injury.

  7. Arterial Spin Labeling Measurements of Cerebral Perfusion Territories in Experimental Ischemic Stroke

    PubMed Central

    Leoni, Renata F.; Paiva, Fernando F.; Kang, Byeong-Teck; Henning, Erica C.; Nascimento, George C.; Tannús, Alberto; De Araújo, Dráulio B.; Silva, Afonso C.

    2016-01-01

    Collateral circulation, defined as the supplementary vascular network that maintains cerebral blood flow (CBF) when the main vessels fail, constitutes one important defense mechanism of the brain against ischemic stroke. In the present study, continuous arterial spin labeling (CASL) was used to quantify CBF and obtain perfusion territory maps of the major cerebral arteries in spontaneously hypertensive rats (SHR) and their normotensive Wistar-Kyoto (WKY) controls. Results show that both WKY and SHR have complementary, yet significantly asymmetric perfusion territories. Right or left dominances were observed in territories of the anterior (ACA), middle and posterior cerebral arteries, and the thalamic artery. Magnetic resonance angiography showed that some of the asymmetries were correlated with variations of the ACA. The leptomeningeal circulation perfusing the outer layers of the cortex was observed as well. Significant and permanent changes in perfusion territories were obtained after temporary occlusion of the right middle cerebral artery in both SHR and WKY, regardless of their particular dominance. However, animals with right dominance presented a larger volume change of the left perfusion territory (23 ± 9%) than animals with left dominance (7 ± 5%, P < 0.002). The data suggest that animals with contralesional dominance primarily safeguard local CBF values with small changes in contralesional perfusion territory, while animals with ipsilesional dominance show a reversal of dominance and a substantial increase in contralesional perfusion territory. These findings show the usefulness of CASL to probe the collateral circulation. PMID:24323754

  8. Modeling the inflammatory response in the hypothalamus ensuing heat stroke: iterative cycle of model calibration, identifiability analysis, experimental design and data collection.

    PubMed

    Klett, Hagen; Rodriguez-Fernandez, Maria; Dineen, Shauna; Leon, Lisa R; Timmer, Jens; Doyle, Francis J

    2015-02-01

    Heat Stroke (HS) is a life-threatening illness caused by prolonged exposure to heat that causes severe hyperthermia and nervous system abnormalities. The long term consequences of HS are poorly understood and deeper insight is required to find possible treatment strategies. Elevated pro- and anti-inflammatory cytokines during HS recovery suggest to play a major role in the immune response. In this study, we developed a mathematical model to understand the interactions and dynamics of cytokines in the hypothalamus, the main thermoregulatory center in the brain. Uncertainty and identifiability analysis of the calibrated model parameters revealed non-identifiable parameters due to the limited amount of data. To overcome the lack of identifiability of the parameters, an iterative cycle of optimal experimental design, data collection, re-calibration and model reduction was applied and further informative experiments were suggested. Additionally, a new method of approximating the prior distribution of the parameters for Bayesian optimal experimental design based on the profile likelihood is presented.

  9. Caloric Vestibular Stimulation Reduces Pain and Somatoparaphrenia in a Severe Chronic Central Post-Stroke Pain Patient: A Case Study.

    PubMed

    Spitoni, Grazia Fernanda; Pireddu, Giorgio; Galati, Gaspare; Sulpizio, Valentina; Paolucci, Stefano; Pizzamiglio, Luigi

    2016-01-01

    Central post-stroke pain is a neuropathic syndrome characterized by intolerable contralesional pain and, in rare cases, somatic delusions. To date, there is limited evidence for the effective treatments of this disease. Here we used caloric vestibular stimulation to reduce pain and somatoparaphrenia in a 57-year-old woman suffering from central post-stroke pain. Resting-state functional magnetic resonance imaging was used to assess the neurological effects of this treatment. Following vestibular stimulation we observed impressive improvements in motor skills, pain, and somatic delusions. In the functional connectivity study before the vestibular stimulation, we observed differences in the patient's left thalamus functional connectivity, with respect to the thalamus connectivity of a control group (N = 20), in the bilateral cingulate cortex and left insula. After the caloric stimulation, the left thalamus functional connectivity with these regions, which are known to be involved in the cortical response to pain, disappeared as in the control group. The beneficial use of vestibular stimulation in the reduction of pain and somatic delusion in a CPSP patient is now documented by behavioral and imaging data. This evidence can be applied to theoretical models of pain and body delusions. PMID:27028404

  10. Caloric Vestibular Stimulation Reduces Pain and Somatoparaphrenia in a Severe Chronic Central Post-Stroke Pain Patient: A Case Study

    PubMed Central

    2016-01-01

    Central post-stroke pain is a neuropathic syndrome characterized by intolerable contralesional pain and, in rare cases, somatic delusions. To date, there is limited evidence for the effective treatments of this disease. Here we used caloric vestibular stimulation to reduce pain and somatoparaphrenia in a 57-year-old woman suffering from central post-stroke pain. Resting-state functional magnetic resonance imaging was used to assess the neurological effects of this treatment. Following vestibular stimulation we observed impressive improvements in motor skills, pain, and somatic delusions. In the functional connectivity study before the vestibular stimulation, we observed differences in the patient’s left thalamus functional connectivity, with respect to the thalamus connectivity of a control group (N = 20), in the bilateral cingulate cortex and left insula. After the caloric stimulation, the left thalamus functional connectivity with these regions, which are known to be involved in the cortical response to pain, disappeared as in the control group. The beneficial use of vestibular stimulation in the reduction of pain and somatic delusion in a CPSP patient is now documented by behavioral and imaging data. This evidence can be applied to theoretical models of pain and body delusions. PMID:27028404

  11. Estrogen Replacement Therapy for Stroke

    PubMed Central

    Pabon, Mibel; Tamboli, Cyrus; Tamboli, Sarosh; Acosta, Sandra; De La Pena, Ike; Sanberg, Paul R.; Tajiri, Naoki; Kaneko, Yuji; Borlongan, Cesar V.

    2014-01-01

    Stroke is the third most common cause of death and severe disability among Western populations. Overall, the incidence of stroke is uniformly higher in men than in women. Stroke is rare in women during the reproductive years and rapidly increases after menopause, strongly suggesting that estrogen (E2) plays an important role in the prevention of stroke. Ongoing studies are currently evaluating both the benefits and the risks associated with E2 replacement therapy and hormone replacement therapy in stroke. Equally important is the role of E2 receptor (ER), as studies indicate that ER populations in several tissue sites may significantly change during stress and aging. Such changes may affect the patient’s susceptibility to neurological disorders including stroke and greatly affect the response to selective E2 receptor modulators (SERMs). Replacement therapies may be inefficient with low ER levels. The goal of this review paper is to discuss an animal model that will allow investigations of the potential therapeutic effects of E2 and its derivatives in stroke. We hypothesize that E2 neuroprotection is, in part, receptor mediated. This hypothesis is a proof-of-principle approach to demonstrate a role for specific ER subtypes in E2 neuroprotection. To accomplish this, we use a retroviral-mediated gene transfer strategy that expresses subtypes of the ER gene in regions of the rat brain most susceptible to neuronal damage, namely, the striatum and the cortex. The animal model is exposed to experimental stroke conditions involving middle cerebral artery occlusion (MCAo) method, and eventually the extent of neuronal damage will be evaluated. A reduction in neuronal damage is expected when E2 is administered with specific ER subtypes. From this animal model, an optimal E2 dose and treatment regimen can be determined. The animal model can help identify potential E2-like therapeutics in stroke and screen for beneficial or toxic additives present in commercial E2

  12. Neuropsychiatric sequelae of stroke.

    PubMed

    Ferro, José M; Caeiro, Lara; Figueira, Maria Luísa

    2016-05-01

    Stroke survivors are often affected by psychological distress and neuropsychiatric disturbances. About one-third of stroke survivors experience depression, anxiety or apathy, which are the most common neuropsychiatric sequelae of stroke. Neuropsychiatric sequelae are disabling, and can have a negative influence on recovery, reduce quality of life and lead to exhaustion of the caregiver. Despite the availability of screening instruments and effective treatments, neuropsychiatric disturbances attributed to stroke are currently underdiagnosed and undertreated. Stroke severity, stroke-related disabilities, cerebral small vessel disease, previous psychiatric disease, poor coping strategies and unfavourable psychosocial environment influence the presence and severity of the psychiatric sequelae of stroke. Although consistent associations between psychiatric disturbances and specific stroke locations have yet to be confirmed, functional MRI studies are beginning to unveil the anatomical networks that are disrupted in stroke-associated psychiatric disorders. Evidence regarding biochemical and genetic biomarkers for stroke-associated psychiatric disorders is still limited, and better understanding of the biological determinants and pathophysiology of these disorders is needed. Investigation into the management of these conditions must be continued, and should include pilot studies to assess the benefits of innovative behavioural interventions and large-scale cooperative randomized controlled pharmacological trials of drugs that are safe to use in patients with stroke. PMID:27063107

  13. Salvianolic acid B attenuates apoptosis and inflammation via SIRT1 activation in experimental stroke rats.

    PubMed

    Lv, Hongdi; Wang, Ling; Shen, Jinchang; Hao, Shaojun; Ming, Aimin; Wang, Xidong; Su, Feng; Zhang, Zhengchen

    2015-06-01

    Silent information regulator 1 (SIRT1), a histone deacetylase, has been suggested to be effective in ischemic brain diseases. Salvianolic acid B (SalB) is a polyphenolic and one of the active components of Salvia miltiorrhiza Bunge. Previous studies suggested that SalB is protective against ischemic stroke. However, the role of SIRT1 in the protective effect of SalB against cerebral ischemia has not been explored. In this study, the rat brain was subjected to middle cerebral artery occlusion (MCAO). Before this surgery, rats were intraperitoneally administrated SalB with or without EX527, a specific SIRT1 inhibitor. The infarct volume, neurological score and brain water content were assessed. In addition, levels of TNF-α and IL-1β in the brain tissues were detected by commercial ELISA kits. And the expression levels of SIRT, Ac-FOXO1, Bcl-2 and Bax were detected by Western blot. The results suggested that SalB exerted a cerebral-protective effect, as shown by reduced infarct volume, lowered brain edema and increased neurological scores. SalB also exerted anti-inflammatory effects as indicated by the decreased TNF-α and IL-1β levels in the brain tissue. Moreover, SalB upregulated the expression of SIRT1 and Bcl-2 and downregulated the expression of Ac-FOXO1 and Bax. These effects of SalB were abolished by EX527 treatment. In summary, our results demonstrate that SalB treatment attenuates brain injury induced by ischemic stoke via reducing apoptosis and inflammation through the activation of SIRT1 signaling. PMID:25981395

  14. Transplantation of cryopreserved human umbilical cord blood mononuclear cells does not induce sustained recovery after experimental stroke in spontaneously hypertensive rats

    PubMed Central

    Weise, Gesa; Lorenz, Marlene; Pösel, Claudia; Maria Riegelsberger, Ute; Störbeck, Veronika; Kamprad, Manja; Kranz, Alexander; Wagner, Daniel-Christoph; Boltze, Johannes

    2014-01-01

    Previous studies have highlighted the enormous potential of cell-based therapies for stroke not only to prevent ischemic brain damage, but also to amplify endogenous repair processes. Considering its widespread availability and low immunogenicity human umbilical cord blood (HUCB) is a particularly attractive stem cell source. Our goal was to investigate the neurorestorative potential of cryopreserved HUCB mononuclear cells (MNC) after permanent middle cerebral artery occlusion (MCAO) in spontaneously hypertensive rats (SHR). Human umbilical cord blood MNC or vehicle solution was administered intravenously 24 hours after MCAO. Experimental groups were as follows: (1) quantitative polymerase chain reaction (PCR) of host-derived growth factors up to 48 hours after stroke; (2) immunohistochemical analysis of astroglial scarring; (3) magnetic resonance imaging (MRI) and weekly behavioral tests for 2 months after stroke. Long-term functional outcome and lesion development on MRI were not beneficially influenced by HUCB MNC therapy. Furthermore, HUCB MNC treatment did not change local growth factor levels and glial scarring extent. In summary, we could not demonstrate neurorestorative properties of HUCB MNC after stroke in SHR. Our results advise caution regarding a prompt translation of cord blood therapy into clinical stroke trials as long as deepened knowledge about its precise modes of action is missing. PMID:24169850

  15. Transplantation of cryopreserved human umbilical cord blood mononuclear cells does not induce sustained recovery after experimental stroke in spontaneously hypertensive rats.

    PubMed

    Weise, Gesa; Lorenz, Marlene; Pösel, Claudia; Maria Riegelsberger, Ute; Störbeck, Veronika; Kamprad, Manja; Kranz, Alexander; Wagner, Daniel-Christoph; Boltze, Johannes

    2014-01-01

    Previous studies have highlighted the enormous potential of cell-based therapies for stroke not only to prevent ischemic brain damage, but also to amplify endogenous repair processes. Considering its widespread availability and low immunogenicity human umbilical cord blood (HUCB) is a particularly attractive stem cell source. Our goal was to investigate the neurorestorative potential of cryopreserved HUCB mononuclear cells (MNC) after permanent middle cerebral artery occlusion (MCAO) in spontaneously hypertensive rats (SHR). Human umbilical cord blood MNC or vehicle solution was administered intravenously 24 hours after MCAO. Experimental groups were as follows: (1) quantitative polymerase chain reaction (PCR) of host-derived growth factors up to 48 hours after stroke; (2) immunohistochemical analysis of astroglial scarring; (3) magnetic resonance imaging (MRI) and weekly behavioral tests for 2 months after stroke. Long-term functional outcome and lesion development on MRI were not beneficially influenced by HUCB MNC therapy. Furthermore, HUCB MNC treatment did not change local growth factor levels and glial scarring extent. In summary, we could not demonstrate neurorestorative properties of HUCB MNC after stroke in SHR. Our results advise caution regarding a prompt translation of cord blood therapy into clinical stroke trials as long as deepened knowledge about its precise modes of action is missing. PMID:24169850

  16. Embolic Stroke due to a Common Carotid Artery Thrombus in a Young Patient with Severe Iron-Deficiency Anemia without Thrombocytosis

    PubMed Central

    2016-01-01

    This case report describes a 41-year-old previously healthy male who presented with stuttering transient ischemic symptoms and radiographic evidence of a left common carotid artery thrombus as well as acute and subacute ischemic infarcts in the left middle cerebral artery territory. An exhaustive stroke work-up did not provide a plausible etiology for his symptoms. His complete blood count and iron studies, however, revealed evidence of severe iron-deficiency anemia without reactive thrombocytosis. His stool guaiac test was positive. He was discharged home on oral antithrombotic agents and aggressive iron replacement therapy with a plan for repeat vascular imaging in 3 months and a colonoscopy. This case report suggests that severe iron-deficiency anemia with or without reactive thrombocytosis should be viewed as a possible hematologic condition associated with thrombotic tendencies and a risk factor for ischemic stroke, especially in young adults. Aggressive iron supplementation and short-term antithrombotic therapy with follow-up vascular imaging are a reasonable treatment for these patients. PMID:27752375

  17. Sex differences in stroke.

    PubMed

    Haast, Roy A M; Gustafson, Deborah R; Kiliaan, Amanda J

    2012-12-01

    Sex differences in stroke are observed across epidemiologic studies, pathophysiology, treatments, and outcomes. These sex differences have profound implications for effective prevention and treatment and are the focus of this review. Epidemiologic studies reveal a clear age-by-sex interaction in stroke prevalence, incidence, and mortality. While premenopausal women experience fewer strokes than men of comparable age, stroke rates increase among postmenopausal women compared with age-matched men. This postmenopausal phenomenon, in combination with living longer, are reasons for women being older at stroke onset and suffering more severe strokes. Thus, a primary focus of stroke prevention has been based on sex steroid hormone-dependent mechanisms. Sex hormones affect different (patho)physiologic functions of the cerebral circulation. Clarifying the impact of sex hormones on cerebral vasculature using suitable animal models is essential to elucidate male-female differences in stroke pathophysiology and development of sex-specific treatments. Much remains to be learned about sex differences in stroke as anatomic and genetic factors may also contribute, revealing its multifactorial nature. In addition, the aftermath of stroke appears to be more adverse in women than in men, again based on older age at stroke onset, longer prehospital delays, and potentially, differences in treatment.

  18. Mental Practice Combined with Motor Rehabilitation to Treat Upper Limb Hemiparesis of Post-Stroke Patients: Clinical and Experimental Evidence.

    PubMed

    Machado, Sergio; Lattari, Eduardo; Paes, Flávia; Rocha, Nuno B F; Nardi, Antonio E; Arias-Carrión, Oscar; Mura, Gioia; Yuan, Ti-Fei; Carta, Mauro G; Campos, Carlos

    2016-01-01

    Stroke is one of the major causes of disability in the world. Due to the extended lifetime of the world's population, the number of people affected by stroke has increased substantially over the last years. Stroke may lead to sensorimotor deficits, usually causing hemiplegia or hemiparesia. In order to reduce motor deficits and accelerate functional recovery, MP combined with motor rehabilitation was introduced to the rehabilitation process of post-stroke patients. Evidence has shown that MP combining with motor rehabilitation based on activities of daily living was more effective than conventional motor rehabilitation used per se. This combination proved very useful and effective, with significant results in improvement of motor deficits in post-stroke patients. However, further studies must be conducted to determine specific parameters, such as type of imagery, frequency or duration. PMID:27346996

  19. Mental Practice Combined with Motor Rehabilitation to Treat Upper Limb Hemiparesis of Post-Stroke Patients: Clinical and Experimental Evidence.

    PubMed

    Machado, Sergio; Lattari, Eduardo; Paes, Flávia; Rocha, Nuno B F; Nardi, Antonio E; Arias-Carrión, Oscar; Mura, Gioia; Yuan, Ti-Fei; Carta, Mauro G; Campos, Carlos

    2016-01-01

    Stroke is one of the major causes of disability in the world. Due to the extended lifetime of the world's population, the number of people affected by stroke has increased substantially over the last years. Stroke may lead to sensorimotor deficits, usually causing hemiplegia or hemiparesia. In order to reduce motor deficits and accelerate functional recovery, MP combined with motor rehabilitation was introduced to the rehabilitation process of post-stroke patients. Evidence has shown that MP combining with motor rehabilitation based on activities of daily living was more effective than conventional motor rehabilitation used per se. This combination proved very useful and effective, with significant results in improvement of motor deficits in post-stroke patients. However, further studies must be conducted to determine specific parameters, such as type of imagery, frequency or duration.

  20. Mental Practice Combined with Motor Rehabilitation to Treat Upper Limb Hemiparesis of Post-Stroke Patients: Clinical and Experimental Evidence

    PubMed Central

    Machado, Sergio; Lattari, Eduardo; Paes, Flávia; Rocha, Nuno B.F.; Nardi, Antonio E.; Arias-Carrión, Oscar; Mura, Gioia; Yuan, Ti-Fei; Carta, Mauro G.; Campos, Carlos

    2016-01-01

    Stroke is one of the major causes of disability in the world. Due to the extended lifetime of the world's population, the number of people affected by stroke has increased substantially over the last years. Stroke may lead to sensorimotor deficits, usually causing hemiplegia or hemiparesia. In order to reduce motor deficits and accelerate functional recovery, MP combined with motor rehabilitation was introduced to the rehabilitation process of post-stroke patients. Evidence has shown that MP combining with motor rehabilitation based on activities of daily living was more effective than conventional motor rehabilitation used per se. This combination proved very useful and effective, with significant results in improvement of motor deficits in post-stroke patients. However, further studies must be conducted to determine specific parameters, such as type of imagery, frequency or duration. PMID:27346996

  1. [Experimental model of severe local radiation injuries of the skin after X-rays].

    PubMed

    Kotenko, K V; Moroz, B B; Nasonova, T A; Dobrynina, O A; LIpengolz, A A; Gimadova, T I; Deshevoy, Yu B; Lebedev, V G; Lyrschikova, A V; Eremin, I I

    2013-01-01

    The experimental model of severe local radiation injuries skin under the influence of a relatively soft X-rays on a modified device RAP 100-10 produced by "Diagnostica-M" (Russia) was proposed. The model can be used as pre-clinical studies in small experimental animals in order to improve the treatment of local radiation injuries, especially in the conditions of application of cellular therapy.

  2. Experimental investigation on the wing-wake interaction at the mid stroke in hovering flight of dragonfly

    NASA Astrophysics Data System (ADS)

    Lai, GuoJun; Shen, GongXin

    2012-11-01

    This paper focuses on flow structures of the wing-wake interaction between the hind wing and the wake of the forewing in hovering flight of a dragonfly since there are arguments whether the wing-wake interaction is useful or not. A mechanical flapping model with two tandem wings is used to study the interaction. In the device, two identical simplified model wings are mounted to the flapping model and they are both scaled up to keep the Reynolds number similar to those of dragonfly in hovering flight since our experiment is conducted in a water tank. The kinetic pattern of dragonfly ( Aeschna juncea) is chosen because of its special interesting asymmetry. A multi-slice phase-locked stereo particle image velocimetry (PIV) system is used to record flow structures around the hind wing at the mid downstroke ( t/ T=0.25) and the mid upstroke ( t/ T=0.75). To make comparison of the flow field between with and without the influence of the wake, flow structures around a single flapping wing (hind wing without the existence of the forewing) at these two stroke phases are also recorded. A local vortex identification scheme called swirling strength is applied to determine the vortices around the wing and they are visualized with the iso-surface of swirling strength. This paper also presents contour lines of ω z at each spanwise position of the hind wing, the vortex core position of the leading edge vortex (LEV) of hind wing with respect to the upper surface of hind wing, the circulation of the hind wing LEV at each spanwise position and so on. Experimental results show that dimension and strength of the hind wing LEV are impaired at the mid stroke in comparison with the single wing LEV because of the downwash from the forewing. Our results also reveal that a wake vortex from the forewing traverses the upper surface of the hind wing at the mid downstroke and its distance to the upper surface is about 40% of the wing chord length. At the instant, the distance of the hind wing

  3. Ischemic Stroke

    MedlinePlus

    ... Spread the Word Advocate Share Spread the Word Contact Us Contact Us 1-800-STROKES (787-6537) 9707 E. ... Stroke En Espanol Stroke Facts Come Back Strong Contact Us 1-800-787-6537 9707 E. Easter ...

  4. Stroke Rehabilitation

    MedlinePlus

    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 ...

  5. Hemorrhagic Stroke

    MedlinePlus

    A stroke is a medical emergency. There are two types - ischemic and hemorrhagic. Hemorrhagic stroke is the less common type. It happens when ... an artery wall that breaks open. Symptoms of stroke are Sudden numbness or weakness of the face, ...

  6. Stroke - discharge

    MedlinePlus

    ... National Institute of Neurological Disorders and Stroke. Post-stroke rehabilitation fact sheet. Available at: www.ninds.nih.gov/disorders/stroke/poststrokerehab.htm . Accessed September 2, 2014. The American ...

  7. Theoretical, Experimental, and Computational Evaluation of Several Vane-Type Slow-Wave Structures

    NASA Technical Reports Server (NTRS)

    Wallett, Thomas M.; Qureshi, A. Haq

    1994-01-01

    Several types of periodic vane slow-wave structures were fabricated. The dispersion characteristics were found by theoretical analysis, experimental testing, and computer simulation using the MAFIA code. Computer-generated characteristics agreed to approximately within 2 percent of the experimental characteristics for all structures. The theoretical characteristics, however, deviated increasingly as the width to height ratio became smaller. Interaction impedances were also computed based on the experimental and computer-generated resonance frequency shifts due to the introduction of a perturbing dielectric rod.

  8. Stroke rehabilitation.

    PubMed

    Langhorne, Peter; Bernhardt, Julie; Kwakkel, Gert

    2011-05-14

    Stroke is a common, serious, and disabling global health-care problem, and rehabilitation is a major part of patient care. There is evidence to support rehabilitation in well coordinated multidisciplinary stroke units or through provision of early supported provision of discharge teams. Potentially beneficial treatment options for motor recovery of the arm include constraint-induced movement therapy and robotics. Promising interventions that could be beneficial to improve aspects of gait include fitness training, high-intensity therapy, and repetitive-task training. Repetitive-task training might also improve transfer functions. Occupational therapy can improve activities of daily living; however, information about the clinical effect of various strategies of cognitive rehabilitation and strategies for aphasia and dysarthria is scarce. Several large trials of rehabilitation practice and of novel therapies (eg, stem-cell therapy, repetitive transcranial magnetic stimulation, virtual reality, robotic therapies, and drug augmentation) are underway to inform future practice.

  9. [Hippocampal stroke].

    PubMed

    Rollnik, J D; Traitel, B; Dietrich, B; Lenz, O

    2015-02-01

    Unilateral cerebral ischemia of the hippocampus is very rare. This paper reviews the literature and presents the case of a 59-year-old woman with an amnestic syndrome due to a left hippocampal stroke. The patient suffered from retrograde amnesia which was most severe over the 2 days prior to presenting and a slight anterograde amnesia. In addition, a verbal memory disorder was confirmed 1 week after admission by neurological tests. As risk factors, arterial hypertension and a relative hyper-beta lipoproteinemia were found. This case shows that unilateral amnestic stroke, e.g. in the hippocampus region, may be the cause of an amnestic syndrome and should be included in the differential diagnostics.

  10. An Economic Evaluation Comparing Stroke Telemedicine to Conventional Stroke Medicine

    ERIC Educational Resources Information Center

    Budhram, Stanley Chandra

    2011-01-01

    Stroke is not only a serious medical problem, but it also poses an enormous economic burden on society. Stroke ranks the third as the leading cause of death in the United States behind heart disease and cancer. The survivors of stroke suffer from various degrees of long-term disability which create a severe financial burden on society. University…

  11. Phytochemicals in Ischemic Stroke.

    PubMed

    Kim, Joonki; Fann, David Yang-Wei; Seet, Raymond Chee Seong; Jo, Dong-Gyu; Mattson, Mark P; Arumugam, Thiruma V

    2016-09-01

    Stroke is the second foremost cause of mortality worldwide and a major cause of long-term disability. Due to changes in lifestyle and an aging population, the incidence of stroke continues to increase and stroke mortality predicted to exceed 12 % by the year 2030. However, the development of pharmacological treatments for stroke has failed to progress much in over 20 years since the introduction of the thrombolytic drug, recombinant tissue plasminogen activator. These alarming circumstances caused many research groups to search for alternative treatments in the form of neuroprotectants. Here, we consider the potential use of phytochemicals in the treatment of stroke. Their historical use in traditional medicine and their excellent safety profile make phytochemicals attractive for the development of therapeutics in human diseases. Emerging findings suggest that some phytochemicals have the ability to target multiple pathophysiological processes involved in stroke including oxidative stress, inflammation and apoptotic cell death. Furthermore, epidemiological studies suggest that the consumption of plant sources rich in phytochemicals may reduce stroke risk, and so reinforce the possibility of developing preventative or neuroprotectant therapies for stroke. In this review, we describe results of preclinical studies that demonstrate beneficial effects of phytochemicals in experimental models relevant to stroke pathogenesis, and we consider their possible mechanisms of action. PMID:27193940

  12. Cryptogenic stroke

    PubMed Central

    Yaghi, Shadi

    2014-01-01

    Summary Cryptogenic, or unexplained, stroke is present in about 30%–40% of ischemic stroke patients. Pursuing a stroke mechanism is important in such patients to better choose therapy to reduce the stroke recurrence risk. Intracranial vessel imaging and cardiac evaluation with transesophageal echocardiogram and outpatient cardiac monitoring may help identify the stroke mechanism. This article highlights the diagnostic yield of various tests in identifying a stroke mechanism in stroke patients whose initial diagnostic evaluation is negative, and the implications for treatment. PMID:25317376

  13. Mechanisms of perinatal arterial ischemic stroke

    PubMed Central

    Fernández-López, David; Natarajan, Niranjana; Ashwal, Stephen; Vexler, Zinaida S

    2014-01-01

    The incidence of perinatal stroke is high, similar to that in the elderly, and produces a significant morbidity and severe long-term neurologic and cognitive deficits, including cerebral palsy, epilepsy, neuropsychological impairments, and behavioral disorders. Emerging clinical data and data from experimental models of cerebral ischemia in neonatal rodents have shown that the pathophysiology of perinatal brain damage is multifactorial. These studies have revealed that, far from just being a smaller version of the adult brain, the neonatal brain is unique with a very particular and age-dependent responsiveness to hypoxia–ischemia and focal arterial stroke. In this review, we discuss fundamental clinical aspects of perinatal stroke as well as some of the most recent and relevant findings regarding the susceptibility of specific brain cell populations to injury, the dynamics and the mechanisms of neuronal cell death in injured neonates, the responses of neonatal blood–brain barrier to stroke in relation to systemic and local inflammation, and the long-term effects of stroke on angiogenesis and neurogenesis. Finally, we address translational strategies currently being considered for neonatal stroke as well as treatments that might effectively enhance repair later after injury. PMID:24667913

  14. Impaired Leptomeningeal Collateral Flow Contributes to the Poor Outcome following Experimental Stroke in the Type 2 Diabetic Mice

    PubMed Central

    Akamatsu, Yosuke; Nishijima, Yasuo; Lee, Chih Cheng; Yang, Shih Yen; Shi, Lei; An, Lin; Wang, Ruikang K.; Tominaga, Teiji

    2015-01-01

    Collateral status is an independent predictor of stroke outcome. However, the spatiotemporal manner in which collateral flow maintains cerebral perfusion during cerebral ischemia is poorly understood. Diabetes exacerbates ischemic brain damage, although the impact of diabetes on collateral dynamics remains to be established. Using Doppler optical coherent tomography, a robust recruitment of leptomeningeal collateral flow was detected immediately after middle cerebral artery (MCA) occlusion in C57BL/6 mice, and it continued to grow over the course of 1 week. In contrast, an impairment of collateral recruitment was evident in the Type 2 diabetic db/db mice, which coincided with a worse stroke outcome compared with their normoglycemic counterpart db/+, despite their equally well-collateralized leptomeningeal anastomoses. Similar to the wild-type mice, both db/+ and db/db mice underwent collateral growth 7 d after MCA stroke, although db/db mice still exhibited significantly reduced retrograde flow into the MCA territory chronically. Acutely induced hyperglycemia in the db/+ mice did not impair collateral flow after stroke, suggesting that the state of hyperglycemia alone was not sufficient to impact collateral flow. Human albumin was efficacious in improving collateral flow and outcome after stroke in the db/db mice, enabling perfusion to proximal MCA territory that was usually not reached by retrograde flow from anterior cerebral artery without treatment. Our results suggest that the impaired collateral status contributes to the exacerbated ischemic injury in mice with Type 2 diabetes, and modulation of collateral flow has beneficial effects on stroke outcome among these subjects. PMID:25740515

  15. [Cerebellar stroke].

    PubMed

    Paradowski, Michał; Zimny, Anna; Paradowski, Bogusław

    2015-01-01

    Cerebellar stroke belongs to a group of rare diseases of vascular origin. Cerebellum, supplied by three pairs of arteries (AICA, PICA, SCA) with many anastomoses between them is less susceptible for a stroke, especially ischemic one. Diagnosis of the stroke in this region is harder due to lower sensibility of commonly used CT of the head in case of stroke suspicion. The authors highlight clinical symptoms distinguishing between vascular territories or topographical locations of the stroke, diagnostic procedures, classical and surgical treatment, the most common misdiagnoses are also mentioned. The authors suggest a diagnostic and therapeutic algorithm development, including rtPA treatment criteria for ischemic cerebellar stroke. PMID:26181157

  16. Decline of microtubule-associated protein tau after experimental stroke in differently aged wild-type and 3xTg mice with Alzheimer-like alterations.

    PubMed

    Michalski, Dominik; Preißler, Hartmut; Hofmann, Sarah; Kacza, Johannes; Härtig, Wolfgang

    2016-08-25

    Stroke therapies are still limited to a minority of patients. Considering time-dependent aspects of stroke, the penumbra concept describes the transition from functional to permanent tissue damage. Thereby, the role of cytoskeletal elements, as for instance microtubules with associated tau remains poorly understood and is therefore not yet considered for therapeutic approaches. This study explored the expression of microtubule-associated protein tau related to neuronal damage in stroke-affected brain regions. Wild-type and triple-transgenic mice of 3, 7 and 12months of age and with an Alzheimer-like background underwent experimental stroke. After 24h, brain sections were used for immunofluorescence labeling of tau and Neuronal Nuclei (NeuN). Potential functional consequences of cellular alterations were explored by statistical relationships to the general health condition, i.e. neurobehavioral deficits and loss of body weight. Immunoreactivity for whole tau decreased significantly in ischemic areas, while the decline at the border zone was more drastic for tau-immunoreactivity compared with the diminished NeuN labeling. Quantitative analyses confirmed pronounced sensitivity for tau-immunoreactivity in the ischemic border zone. Decline of tau- as well as NeuN-immunoreactivity correlated with body weight loss during the 24-h observation period. In conclusion, microtubule-associated protein tau was robustly identified as a highly sensitive cytoskeletal constitute under ischemic conditions, suggesting a pivotal role during the transition process toward long-lasting tissue damage. Consequently, cytoskeletal elements appear as promising targets for novel therapeutic approaches with the objective to impede ischemia-induced irreversible cellular degradation.

  17. Rehabilitation approaches to stroke.

    PubMed

    Aichner, F; Adelwöhrer, C; Haring, H P

    2002-01-01

    This article describes the state of the science in stroke rehabilitation dealing with three main topics: (1) General approach to stroke rehabilitation (stroke services and stroke units), (2) Neurophysiological and pharmacological interventions (facilitation of brain repair mechanisms) and (3) Experimental approaches (neuronal transplantation). Stroke rehabilitation is an active process beginning during acute hospitalisation, progressing to a systematic program of rehabilitation services and continuing after the individual returns to the community. There is world-wide consensus that stroke patients should be treated at specialised stroke unit with specially trained medical and nursing staff, co-ordinated multidisciplinary rehabilitation and education programs for patients and their families. Stroke Unit has been shown to be associated with a long-term reduction of death and of the combined poor outcomes of death and dependency, independent of patients age, sex, or variations in stroke unit organisations. No study has clearly shown to what extent the beneficial effect is due to specific rehabilitation strategies. New imaging studies in stroke patients indicate altered post stroke activation patterns, which suggest some functional reorganisation. Reorganisation may be the principle process responsible for recovery after stroke. It is assumed that different post ischaemic interventions like physiotherapy, occupational therapy, speech therapy, electrical stimulation, etc. facilitates such changes. Scientific evidence demonstrating the values of specific rehabilitation interventions after stroke is limited. Comparisons between different methods in current use have so far mostly failed to show that any particular physiotherapy, occupational therapy, speech therapy or stroke rehabilitation strategy is superior to another. Clinical data are strongly in favour of early mobilisation and training. Pharmacological interventions in animals revealed that norepinephrine

  18. Yonkenafil: a novel phosphodiesterase type 5 inhibitor induces neuronal network potentiation by a cGMP-dependent Nogo-R axis in acute experimental stroke.

    PubMed

    Chen, Xuemei; Wang, Nannan; Liu, Yueyang; Liu, Yinglu; Zhang, Tianyu; Zhu, Lei; Wang, Yongfeng; Wu, Chunfu; Yang, Jingyu

    2014-11-01

    Yonkenafil is a novel phosphodiesterase type 5 (PDE5) inhibitor. Here we evaluated the effect of yonkenafil on ischemic injury and its possible mechanism of action. Male Sprague-Dawley rats underwent middle cerebral artery occlusion, followed by intraperitoneal or intravenous treatment with yonkenafil starting 2h later. Behavioral tests were carried out on day 1 or day 7 after reperfusion. Nissl staining, Fluoro-Jade B staining and electron microscopy studies were carried out 24h post-stroke, together with an analysis of infarct volume and severity of edema. Levels of cGMP-dependent Nogo-66 receptor (Nogo-R) pathway components, hsp70, apaf-1, caspase-3, caspase-9, synaptophysin, PSD-95/neuronal nitric oxide synthases (nNOS), brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) and nerve growth factor (NGF)/tropomyosin-related kinase A (TrkA) were also measured after 24h. Yonkenafil markedly inhibited infarction and edema, even when administration was delayed until 4h after stroke onset. This protection was associated with an improvement in neurological function and was sustained for 7d. Yonkenafil enlarged the range of penumbra, reduced ischemic cell apoptosis and the loss of neurons, and modulated the expression of proteins in the Nogo-R pathway. Moreover, yonkenafil protected the structure of synapses and increased the expression of synaptophysin, BDNF/TrkB and NGF/TrkA. In conclusion, yonkenafil protects neuronal networks from injury after stroke.

  19. Know Stroke

    MedlinePlus

    ... Director, National Institute of Neurological Disorders and Stroke Photo courtesy of NIH/NINDS Welcome to this special section on stroke, the third leading cause of death in the United States. Each year, there are more than 700, ...

  20. Gonadotropin-releasing hormone reduces the severity of experimental autoimmune encephalomyelitis, a model of multiple sclerosis.

    PubMed

    Quintanar, J Luis; Salinas, Eva; Quintanar-Stephano, Andrés

    2011-02-01

    It has been reported that the spinal cord possesses Gonadotropin-releasing hormone (GnRH) receptor and that GnRH has neurotrophic properties. Experimental autoimmune encephalomyelitis (EAE) causes neurodegeneration in spinal cord. Thus, the present study was designed to determine whether administration of GnRH reduces the severity of EAE. The clinical signs of locomotion, axonal morphometry and neurofilaments (NFs) expression were evaluated. Clinical signs remained significantly lower in EAE rats with GnRH administration compared to animals without treatment. Morphometric analysis, there were more axons of larger areas in the spinal cord of EAE+GnRH group compared to EAE animals. Western blot analysis demonstrated that GnRH administration significantly increased the expression of NFs of 68, 160 and 200kDa in the spinal cord of EAE animals. Our results indicate that GnRH administration reduces the severity of EAE in the rat.

  1. First Experimental In Vivo Model of Enhanced Dengue Disease Severity through Maternally Acquired Heterotypic Dengue Antibodies

    PubMed Central

    Ng, Jowin Kai Wei; Zhang, Summer Lixin; Tan, Hwee Cheng; Yan, Benedict; Maria Martinez Gomez, Julia; Tan, Wei Yu; Lam, Jian Hang; Tan, Grace Kai Xin; Ooi, Eng Eong; Alonso, Sylvie

    2014-01-01

    Dengue (DEN) represents the most serious arthropod-borne viral disease. DEN clinical manifestations range from mild febrile illness to life-threatening hemorrhage and vascular leakage. Early epidemiological observations reported that infants born to DEN-immune mothers were at greater risk to develop the severe forms of the disease upon infection with any serotype of dengue virus (DENV). From these observations emerged the hypothesis of antibody-dependent enhancement (ADE) of disease severity, whereby maternally acquired anti-DENV antibodies cross-react but fail to neutralize DENV particles, resulting in higher viremia that correlates with increased disease severity. Although in vitro and in vivo experimental set ups have indirectly supported the ADE hypothesis, direct experimental evidence has been missing. Furthermore, a recent epidemiological study has challenged the influence of maternal antibodies in disease outcome. Here we have developed a mouse model of ADE where DENV2 infection of young mice born to DENV1-immune mothers led to earlier death which correlated with higher viremia and increased vascular leakage compared to DENV2-infected mice born to dengue naïve mothers. In this ADE model we demonstrated the role of TNF-α in DEN-induced vascular leakage. Furthermore, upon infection with an attenuated DENV2 mutant strain, mice born to DENV1-immune mothers developed lethal disease accompanied by vascular leakage whereas infected mice born to dengue naïve mothers did no display any clinical manifestation. In vitro ELISA and ADE assays confirmed the cross-reactive and enhancing properties towards DENV2 of the serum from mice born to DENV1-immune mothers. Lastly, age-dependent susceptibility to disease enhancement was observed in mice born to DENV1-immune mothers, thus reproducing epidemiological observations. Overall, this work provides direct in vivo demonstration of the role of maternally acquired heterotypic dengue antibodies in the enhancement of dengue

  2. First experimental in vivo model of enhanced dengue disease severity through maternally acquired heterotypic dengue antibodies.

    PubMed

    Ng, Jowin Kai Wei; Zhang, Summer Lixin; Tan, Hwee Cheng; Yan, Benedict; Martinez, Julia Maria; Tan, Wei Yu; Lam, Jian Hang; Tan, Grace Kai Xin; Ooi, Eng Eong; Alonso, Sylvie

    2014-04-01

    Dengue (DEN) represents the most serious arthropod-borne viral disease. DEN clinical manifestations range from mild febrile illness to life-threatening hemorrhage and vascular leakage. Early epidemiological observations reported that infants born to DEN-immune mothers were at greater risk to develop the severe forms of the disease upon infection with any serotype of dengue virus (DENV). From these observations emerged the hypothesis of antibody-dependent enhancement (ADE) of disease severity, whereby maternally acquired anti-DENV antibodies cross-react but fail to neutralize DENV particles, resulting in higher viremia that correlates with increased disease severity. Although in vitro and in vivo experimental set ups have indirectly supported the ADE hypothesis, direct experimental evidence has been missing. Furthermore, a recent epidemiological study has challenged the influence of maternal antibodies in disease outcome. Here we have developed a mouse model of ADE where DENV2 infection of young mice born to DENV1-immune mothers led to earlier death which correlated with higher viremia and increased vascular leakage compared to DENV2-infected mice born to dengue naïve mothers. In this ADE model we demonstrated the role of TNF-α in DEN-induced vascular leakage. Furthermore, upon infection with an attenuated DENV2 mutant strain, mice born to DENV1-immune mothers developed lethal disease accompanied by vascular leakage whereas infected mice born to dengue naïve mothers did no display any clinical manifestation. In vitro ELISA and ADE assays confirmed the cross-reactive and enhancing properties towards DENV2 of the serum from mice born to DENV1-immune mothers. Lastly, age-dependent susceptibility to disease enhancement was observed in mice born to DENV1-immune mothers, thus reproducing epidemiological observations. Overall, this work provides direct in vivo demonstration of the role of maternally acquired heterotypic dengue antibodies in the enhancement of dengue

  3. Pediatric Stroke

    PubMed Central

    Jeong, Goun; Lim, Byung Chan

    2015-01-01

    Pediatric stroke is relatively rare but may lead to significant morbidity and mortality. Along with the advance of brain imaging technology and clinical awareness, diagnosis of pediatric stroke is increasing wordwide. Pediatric stroke differs from adults in variable risk factor/etiologies, diverse and nonspecific clinical presentation depending on ages. This review will be discussed pediatric stroke focusing on their clinical presentations, diagnosis and etiologies/risk factors. PMID:26180605

  4. Effect of E670G Polymorphism in PCSK9 Gene on the Risk and Severity of Coronary Heart Disease and Ischemic Stroke in a Tunisian Cohort.

    PubMed

    Slimani, Afef; Harira, Yahia; Trabelsi, Imen; Jomaa, Walid; Maatouk, Faouzi; Hamda, Khaldoun Ben; Slimane, Mohamed Naceur

    2014-06-01

    The association of E670G (rs505151) polymorphism in PCSK9 gene with an increased risk of coronary artery disease (CAD) and ischemic stroke (IS) was reported in previous studies. We investigated the effect of the E670G (rs505151) on the risk of CAD and IS in a Tunisian cohort. Genotyping of the PCSK9 E670G was performed using polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) and then confirmed by direct sequencing. The frequency of the 670G allele was significantly higher in the CAD than in the no-CAD subgroup (0.132 vs. 0.068, p = 0.030). As expected, the incidence of E670G was significantly important in IS subgroup than control group (0.122 vs. 0.073, p = 0.032). Furthermore in CAD patients, the 670G carriers showed significantly increased plasma total cholesterol and LDL-cholesterol levels compared to E670 carriers (6.78 [6.47-7.00] vs. 4.92 [4.02-5.46] mmol/l, p < 0.0001 and 4.60 [4.00-5.04] vs. 3.00 [2.22-3.70] mmol/l p = 0.001, respectively). The risk and severity of CAD were significantly increased in 670G carriers between no-CAD subgroup and CAD patients presenting a stenosis ≥50 % in two or three major coronary arteries (0.068 vs. 0.198, p = 0.001, OR = 3.39 [1.55-7.37]). The E670G polymorphism of the PCSK9 gene is mainly associated with a increased risk and severity of CAD and IS in Tunisian cohort.

  5. Relation between stroke volume index to risk of death in patients with low-gradient severe aortic stenosis and preserved left ventricular function.

    PubMed

    Maor, Elad; Beigel, Roy; Grupper, Avishay; Kuperstein, Rafael; Hai, Ilan; Medvedofsky, Diego; Perelstein, Olga; Mazin, Israel; Ziv, Asaf; Goldenberg, Ilan; Feinberg, Micha S; Ben Zekry, Sagit

    2014-08-01

    The aim of the present study was to evaluate whether assessment of stroke volume index (SVI) can be used to improve risk stratification among patients with low-gradient severe aortic stenosis and preserved ejection fraction (EF). Study population comprised 409 patients with aortic valve area ≤1.00 cm(2), mean gradient <40 mm Hg, and a normal EF (≥50%) who were followed up in a tertiary referral center from 2004 to 2012. Echocardiographic parameters and clinical data were collected. Multivariate Cox proportional hazards regression modeling was used to evaluate the association between SVI and the risk of all-cause mortality. Mean age of study patients was 78 ± 11 years, and 42% were men. The mean SVI was 39 ± 7 ml/m(2) (tertile 1 = 32 ± 4 ml/m(2); tertile 2 = 39 ± 1 ml/m(2); tertile 3 = 47 ± 4 ml/m(2)). Multivariate analysis showed that the SVI was the most powerful echocardiographic parameter associated with long-term outcome: each 5 ml/m(2) reduction in SVI was associated with a 20% increase in adjusted mortality risk (p = 0.01). Consistently, Kaplan-Meier analysis showed that the cumulative probability of survival during 3 years of follow-up was 60%, 72%, and 73% among patients in the low-, intermediate-, and high-SVI groups, respectively (p = 0.012). Our findings suggest that in patients with low-gradient severe aortic stenosis and preserved EF, there is a graded inverse relation between SVI and the risk of long-term mortality. PMID:24948491

  6. Proteomic Analysis of the Peri-Infarct Area after Human Umbilical Cord Mesenchymal Stem Cell Transplantation in Experimental Stroke

    PubMed Central

    He, Dongsheng; Zhang, Zhuo; Lao, Jiamin; Meng, Hailan; Han, Lijuan; Chen, Fan; Ye, Dan; Zhang, He; Xu, Yun

    2016-01-01

    Among various therapeutic approaches for stroke, treatment with human umbilical cord mesenchymal stem cells (hUC-MSCs) has acquired some promising results. However, the underlying mechanisms remain unclear. We analyzed the protein expression spectrum of the cortical peri-infarction region after ischemic stroke followed by treatment with hUC-MSCs, and found 16 proteins expressed differentially between groups treated with or without hUC-MSCs. These proteins were further determined by Gene Ontology term analysis and network with CD200-CD200R1, CCL21-CXCR3 and transcription factors. Three of them: Abca13, Grb2 and Ptgds were verified by qPCR and ELISA. We found the protein level of Abca13 and the mRNA level of Grb2 consistent with results from the proteomic analysis. Finally, the function of these proteins was described and the potential proteins that deserve to be further studied was also highlighted. Our data may provide possible underlying mechanisms for the treatment of stroke using hUC-MSCs. PMID:27699085

  7. Proteomic Analysis of the Peri-Infarct Area after Human Umbilical Cord Mesenchymal Stem Cell Transplantation in Experimental Stroke

    PubMed Central

    Dongsheng, He; Zhuo, Zhang; Jiamin, Lao; Hailan, Meng; Lijuan, Han; Fan, Chen; Dan, Ye; He, Zhang; Yun, Xu

    2016-01-01

    Among various therapeutic approaches for stroke, treatment with human umbilical cord mesenchymal stem cells (hUC-MSCs) has acquired some promising results. However, the underlying mechanisms remain unclear. We analyzed the protein expression spectrum of the cortical peri-infarction region after ischemic stroke followed by treatment with hUC-MSCs, and found 16 proteins expressed differentially between groups treated with or without hUC-MSCs. These proteins were further determined by Gene Ontology term analysis and network with CD200-CD200R1, CCL21-CXCR3 and transcription factors. Three of them: Abca13, Grb2 and Ptgds were verified by qPCR and ELISA. We found the protein level of Abca13 and the mRNA level of Grb2 consistent with results from the proteomic analysis. Finally, the function of these proteins was described and the potential proteins that deserve to be further studied was also highlighted. Our data may provide possible underlying mechanisms for the treatment of stroke using hUC-MSCs.

  8. Acute ischemic stroke update.

    PubMed

    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

  9. Cerebrorenal interaction and stroke.

    PubMed

    Toyoda, Kazunori

    2013-01-01

    Beyond the original meaning of chronic kidney disease (CKD) as high-risk state for future dialysis, CKD is now known as an established risk factor for cardiovascular diseases. Stroke is a major player of cardiovascular disease and has deep two-way relationships with CKD. CKD is an evident risk factor for stroke. Meta-analyses of cohort studies and trials indicate that proteinuria/albuminuria increases the risk of stroke by 71-92%, and reduced glomerular filtration rate increases the risk by 43%. In addition, CKD has a strong relationship with subclinical brain damage including white matter changes, microbleeds, cognitive impairment, and carotid atherosclerosis. CKD is prevalent in acute stroke patients; patients with estimated glomerular filtration rate <60 ml/min/1.73 m(2) or proteinuria amounted to 46% of total ischemic stroke patients and 39% of total intracerebral hemorrhage patients in our institute. Acute and chronic management of stroke are influenced by CKD. Therapeutic effects of several antithrombotic and thrombolytic agents, including recently-developed novel oral anticoagulants, are affected by renal function. Moreover, reduced glomerular filtration rate is independently associated with increased 1- and 10-year mortalities in the end. Stroke also has deep relationships with end-stage kidney disease. Stroke occurs much more commonly in dialysis patients than general population or CKD patients without need for dialysis. The triggers of ischemic and hemorrhagic stroke in patients with end-stage kidney disease include special characteristics unique to dialysis, such as drastic hemodynamic change, dialysate and anticoagulants, and vascular calcification. As cohorts of dialysis patients become older, more hypertensive, and more diabetic than before, stroke become more prevalent and more serious events in dialysis clinics. Now, clinicians should have much interest in the association between CKD and cerebrovascular diseases, so-called the cerebro

  10. Lipoprotein (a) and stroke

    PubMed Central

    Milionis, H.; Winder, A.; Mikhailidis, D.

    2000-01-01

    Strokes are one of the most common causes of mortality and long term severe disability. There is evidence that lipoprotein (a) (Lp(a)) is a predictor of many forms of vascular disease, including premature coronary artery disease. Several studies have also evaluated the association between Lp(a) and ischaemic (thrombotic) stroke. Several cross sectional (and a few prospective) studies provide contradictory findings regarding Lp(a) as a predictor of ischaemic stroke. Several factors might contribute to the existing confusion—for example, small sample sizes, different ethnic groups, the influence of oestrogens in women participating in the studies, plasma storage before Lp(a) determination, statistical errors, and selection bias. This review focuses on the Lp(a) related mechanisms that might contribute to the pathogenesis of ischaemic stroke. The association between Lp(a) and other cardiovascular risk factors is discussed. Therapeutic interventions that can lower the circulating concentrations of Lp(a) and thus possibly reduce the risk of stroke are also considered. Key Words: atherothrombosis • fibrinogen • homocysteine • lipids • lipoprotein a • stroke PMID:10961170

  11. Macrophage activation associated with chronic murine cytomegalovirus infection results in more severe experimental choroidal neovascularization.

    PubMed

    Cousins, Scott W; Espinosa-Heidmann, Diego G; Miller, Daniel M; Pereira-Simon, Simone; Hernandez, Eleut P; Chien, Hsin; Meier-Jewett, Courtney; Dix, Richard D

    2012-01-01

    The neovascular (wet) form of age-related macular degeneration (AMD) leads to vision loss due to choroidal neovascularization (CNV). Since macrophages are important in CNV development, and cytomegalovirus (CMV)-specific IgG serum titers in patients with wet AMD are elevated, we hypothesized that chronic CMV infection contributes to wet AMD, possibly by pro-angiogenic macrophage activation. This hypothesis was tested using an established mouse model of experimental CNV. At 6 days, 6 weeks, or 12 weeks after infection with murine CMV (MCMV), laser-induced CNV was performed, and CNV severity was determined 4 weeks later by analysis of choroidal flatmounts. Although all MCMV-infected mice exhibited more severe CNV when compared with control mice, the most severe CNV developed in mice with chronic infection, a time when MCMV-specific gene sequences could not be detected within choroidal tissues. Splenic macrophages collected from mice with chronic MCMV infection, however, expressed significantly greater levels of TNF-α, COX-2, MMP-9, and, most significantly, VEGF transcripts by quantitative RT-PCR assay when compared to splenic macrophages from control mice. Direct MCMV infection of monolayers of IC-21 mouse macrophages confirmed significant stimulation of VEGF mRNA and VEGF protein as determined by quantitative RT-PCR assay, ELISA, and immunostaining. Stimulation of VEGF production in vivo and in vitro was sensitive to the antiviral ganciclovir. These studies suggest that chronic CMV infection may serve as a heretofore unrecognized risk factor in the pathogenesis of wet AMD. One mechanism by which chronic CMV infection might promote increased CNV severity is via stimulation of macrophages to make pro-angiogenic factors (VEGF), an outcome that requires active virus replication. PMID:22570607

  12. Macrophage Activation Associated with Chronic Murine Cytomegalovirus Infection Results in More Severe Experimental Choroidal Neovascularization

    PubMed Central

    Cousins, Scott W.; Espinosa-Heidmann, Diego G.; Miller, Daniel M.; Pereira-Simon, Simone; Hernandez, Eleut P.; Chien, Hsin; Meier-Jewett, Courtney; Dix, Richard D.

    2012-01-01

    The neovascular (wet) form of age-related macular degeneration (AMD) leads to vision loss due to choroidal neovascularization (CNV). Since macrophages are important in CNV development, and cytomegalovirus (CMV)-specific IgG serum titers in patients with wet AMD are elevated, we hypothesized that chronic CMV infection contributes to wet AMD, possibly by pro-angiogenic macrophage activation. This hypothesis was tested using an established mouse model of experimental CNV. At 6 days, 6 weeks, or 12 weeks after infection with murine CMV (MCMV), laser-induced CNV was performed, and CNV severity was determined 4 weeks later by analysis of choroidal flatmounts. Although all MCMV-infected mice exhibited more severe CNV when compared with control mice, the most severe CNV developed in mice with chronic infection, a time when MCMV-specific gene sequences could not be detected within choroidal tissues. Splenic macrophages collected from mice with chronic MCMV infection, however, expressed significantly greater levels of TNF-α, COX-2, MMP-9, and, most significantly, VEGF transcripts by quantitative RT-PCR assay when compared to splenic macrophages from control mice. Direct MCMV infection of monolayers of IC-21 mouse macrophages confirmed significant stimulation of VEGF mRNA and VEGF protein as determined by quantitative RT-PCR assay, ELISA, and immunostaining. Stimulation of VEGF production in vivo and in vitro was sensitive to the antiviral ganciclovir. These studies suggest that chronic CMV infection may serve as a heretofore unrecognized risk factor in the pathogenesis of wet AMD. One mechanism by which chronic CMV infection might promote increased CNV severity is via stimulation of macrophages to make pro-angiogenic factors (VEGF), an outcome that requires active virus replication. PMID:22570607

  13. An experimental test of the 'transmission-line model' of electromagnetic radiation from triggered lightning return strokes

    NASA Technical Reports Server (NTRS)

    Willett, J. C.; Idone, V. P.; Orville, R. E.; Leteinturier, C.; Eybert-Berard, A.

    1988-01-01

    Peak currents, two-dimensional average propagation speeds, and electric field waveforms for a number of subsequent return strikes in rocket-triggered lightning flashes were measured in order to test the 'transmission-line model' of return-stroke radiation of Uman and McLain (1970). Reasonable agreement is found between the propagation speeds measured with the streak camera and those deduced from the transmission-line model. A modification of the model is proposed in which two wave fronts travel upward and downward away from a junction point a short distance above the ground.

  14. Imaging acute ischemic stroke.

    PubMed

    González, R Gilberto; Schwamm, Lee H

    2016-01-01

    Acute ischemic stroke is common and often treatable, but treatment requires reliable information on the state of the brain that may be provided by modern neuroimaging. Critical information includes: the presence of hemorrhage; the site of arterial occlusion; the size of the early infarct "core"; and the size of underperfused, potentially threatened brain parenchyma, commonly referred to as the "penumbra." In this chapter we review the major determinants of outcomes in ischemic stroke patients, and the clinical value of various advanced computed tomography and magnetic resonance imaging methods that may provide key physiologic information in these patients. The focus is on major strokes due to occlusions of large arteries of the anterior circulation, the most common cause of a severe stroke syndrome. The current evidence-based approach to imaging the acute stroke patient at the Massachusetts General Hospital is presented, which is applicable for all stroke types. We conclude with new information on time and stroke evolution that imaging has revealed, and how it may open the possibilities of treating many more patients. PMID:27432672

  15. Prehospital stroke care

    PubMed Central

    Saver, Jeffrey L.; Starkman, Sidney; Lees, Kennedy R.; Endres, Matthias

    2013-01-01

    Brain cells die rapidly after stroke and any effective treatment must start as early as possible. In clinical routine, the tight time–outcome relationship continues to be the major limitation of therapeutic approaches: thrombolysis rates remain low across many countries, with most patients being treated at the late end of the therapeutic window. In addition, there is no neuroprotective therapy available, but some maintain that this concept may be valid if administered very early after stroke. Recent innovations have opened new perspectives for stroke diagnosis and treatment before the patient arrives at the hospital. These include stroke recognition by dispatchers and paramedics, mobile telemedicine for remote clinical examination and imaging, and integration of CT scanners and point-of-care laboratories in ambulances. Several clinical trials are now being performed in the prehospital setting testing prehospital delivery of neuroprotective, antihypertensive, and thrombolytic therapy. We hypothesize that these new approaches in prehospital stroke care will not only shorten time to treatment and improve outcome but will also facilitate hyperacute stroke research by increasing the number of study participants within an ultra-early time window. The potentials, pitfalls, and promises of advanced prehospital stroke care and research are discussed in this review. PMID:23897876

  16. Stroke and Stroke-like Episodes in Muscle Disease

    PubMed Central

    Finsterer, Josef

    2012-01-01

    Background: Though not obvious at a first glance, myopathies may be associated with ischemic stroke. Stroke-like episodes resemble ischemic stroke only to some extent but are a unique feature of certain mitochondrial disorders with a pathogenesis at variance from that of ischemic stroke. Only limited data are available about ischemic stroke in pri-mary myopathies and the management of stroke-like episodes in mitochondrial disorders. This review aims to summarize and discuss current knowledge about stroke in myopathies and to delineate stroke-like episodes from ischemic stroke. Methods: Literature review via PubMED using the search terms “stroke”, “cerebrovascular”, “ischemic event”, “stroke-like episode”, “stroke-mimic”, “mitochondrial disorder”. Results: Stroke in myopathies is most frequently cardioembolic due to atrial fibrillation or atrial flutter, dilated cardio-myopathy, or left-ventricular hypertrabeculation (noncompaction). The second most frequent cause of stroke in myopathies is angiopathy from atherosclerosis or vasculitis, which may be a feature of inflammatory myopathies. Athero-sclerosis may either result from classical risk factors, such as diabetes, arterial hypertension, hyperlpidemia, or smoking, associated with muscle disease, or may be an inherent feature of a mitochondrial disorder. In case of severe heart failure from cardiomyopathy as a manifestation of muscle disease low flow infarcts may occur. Thrombophilic stroke has been described in polymyositis and dermatomyositis in association with anti-phospholipid syndrome. Stroke-like episodes occur particularly in mitochondrial encephalopathy, lactacidosis and stroke-likeepisode syndrome but rarely also in Leigh-syndrome and other mitochondrial disorders. Stroke-like episodes are at variance from ischemic stroke, pathogenically, clinically and on imaging. They may be the manifestation of a vascular, metabolic or epileptic process and present with predominantly vasogenic

  17. Severe Changes in Thymic Microenvironment in a Chronic Experimental Model of Paracoccidioidomycosis

    PubMed Central

    Alves da Costa, Thiago; Di Gangi, Rosária; Thomé, Rodolfo; Barreto Felisbino, Marina; Pires Bonfanti, Amanda; Lumi Watanabe Ishikawa, Larissa; Sartori, Alexandrina; Burger, Eva; Verinaud, Liana

    2016-01-01

    T cell maturation takes place within the thymus, a primary lymphoid organ that is commonly targeted during infections. Previous studies showed that acute infection with Paracoccidioides brasiliensis (Pb), the causative agent of paracoccidioidomycosis (PCM), promotes thymic atrophy that is associated with the presence of yeast cells in the organ. However, as human PCM is a chronic infection, it is imperative to investigate the consequences of Pb infection over the thymic structure and function in chronic infection. In this sense, we developed a new experimental model where Pb yeast cells are injected through the intraperitoneal route and mice are evaluated over 120 days of infection. Thymuses were analyzed in chronically infected mice and we found that the thymus underwent extensive morphological alterations and severe infiltration of P. brasiliensis yeast cells. Further analyses showed an altered phenotype and function of thymocytes that are commonly found in peripheral mature T lymphocytes. We also observed activation of the NLRP3 inflammasome in the thymus. Our data provide new information on the severe changes observed in the thymic microenvironment in a model of PCM that more closely mimics the human infection. PMID:27736987

  18. Do robotic and non-robotic arm movement training drive motor recovery after stroke by a common neural mechanism? Experimental evidence and a computational model.

    PubMed

    Reinkensmeyer, David J; Maier, Marc A; Guigon, Emmanuel; Chan, Vicky; Akoner, O; Wolbrecht, Eric T; Cramer, Steven C; Bobrow, James E

    2009-01-01

    Different dose-matched, upper extremity rehabilitation training techniques, including robotic and non-robotic techniques, can result in similar improvement in movement ability after stroke, suggesting they may elicit a common drive for recovery. Here we report experimental results that support the hypothesis of a common drive, and develop a computational model of a putative neural mechanism for the common drive. We compared weekly motor control recovery during robotic and unassisted movement training techniques after chronic stroke (n = 27), as assessed with quantitative measures of strength, speed, and coordination. The results showed that recovery in both groups followed an exponential time course with a time constant of about 4-5 weeks. Despite the greater range and speed of movement practiced by the robot group, motor recovery was very similar between the groups. The premise of the computational model is that improvements in motor control are caused by improvements in the ability to activate spared portions of the damaged corticospinal system, as learned by a biologically plausible search algorithm. Robot-assisted and unassisted training would in theory equally drive this search process.

  19. A comparative study on several models of experimental renal calcium oxalate stones formation in rats.

    PubMed

    Liu, Jihong; Cao, Zhengguo; Zhang, Zhaohui; Zhou, Siwei; Ye, Zhangqun

    2007-02-01

    In order to compare the effects of several experimental renal calcium oxalate stones formation models in rats and to find a simple and convenient model with significant effect of calcium oxalate crystals deposition in the kidney, several rat models of renal calcium oxalate stones formation were induced by some crystal-inducing drugs (CID) including ethylene glycol (EG), ammonium chloride (AC), vitamin D(3)[1alpha(OH)VitD(3), alfacalcidol], calcium gluconate, ammonium oxalate, gentamicin sulfate, L-hydroxyproline. The rats were fed with drugs given singly or unitedly. At the end of experiment, 24-h urines were collected and the serum creatinine (Cr), blood urea nitrogen (BUN), the extents of calcium oxalate crystal deposition in the renal tissue, urinary calcium and oxalate excretion were measured. The serum Cr levels in the stone-forming groups were significantly higher than those in the control group except for the group EG+L-hydroxyproline, group calcium gluconate and group oxalate. Blood BUN concentration was significantly higher in rats fed with CID than that in control group except for group EG+L-hydroxyproline and group ammonium oxalate plus calcium gluconate. In the group of rats administered with EG plus Vitamin D(3), the deposition of calcium oxalate crystal in the renal tissue and urinary calcium excretion were significantly greater than other model groups. The effect of the model induced by EG plus AC was similar to that in the group induced by EG plus Vitamin D(3). EG plus Vitamin D(3) or EG plus AC could stably and significantly induced the rat model of renal calcium oxalate stones formation. PMID:17393118

  20. Induction of IDO-1 by immunostimulatory DNA limits severity of experimental colitis.

    PubMed

    Ciorba, Matthew A; Bettonville, Ellen E; McDonald, Keely G; Metz, Richard; Prendergast, George C; Newberry, Rodney D; Stenson, William F

    2010-04-01

    The chronic inflammatory bowel diseases are characterized by aberrant innate and adaptive immune responses to commensal luminal bacteria. In both human inflammatory bowel disease and in experimental models of colitis, there is an increased expression of the enzyme IDO. IDO expression has the capacity to exert antimicrobial effects and dampen adaptive immune responses. In the murine trinitrobenzene sulfonic acid model of colitis, inhibition of this enzyme leads to worsened disease severity, suggesting that IDO acts as a natural break in limiting colitis. In this investigation, we show that induction of IDO-1 by a TLR-9 agonist, immunostimulatory (ISS) DNA, critically contributes to its colitis limiting capacities. ISS DNA induces intestinal expression of IDO-1 but not the recently described paralog enzyme IDO-2. This induction occurred in both epithelial cells and in subsets of CD11c(+) and CD11b(+) cells of the lamina propria, which also increase after ISS-oligodeoxynucleotide. Signaling required for intestinal IDO-1 induction involves IFN-dependent pathways, as IDO-1 was not induced in STAT-1 knockout mice. Using both the trinitrobenzene sulfonic acid and dextran sodium sulfate models of colitis, we show the importance of IDO-1s induction in limiting colitis severity. The clinical parameters and histological correlates of colitis in these models were improved by administration of the TLR-9 agonist; however, when the function of IDO is inhibited, the colitis limiting effects of ISS-oligodeoxynucleotide were abrogated. These findings support the possibility that targeted induction of IDO-1 is an approach deserving further investigation as a therapeutic strategy for diseases of intestinal inflammation.

  1. Digoxin Inhibits Induction of Experimental Autoimmune Uveitis in Mice, but Causes Severe Retinal Degeneration

    PubMed Central

    Hinshaw, Samuel J. H.; Ogbeifun, Osato; Wandu, Wambui S.; Lyu, Cancan; Shi, Guangpu; Li, Yichao; Qian, Haohua; Gery, Igal

    2016-01-01

    Purpose Digoxin, a major medication for heart disease, was recently reported to have immunosuppressive capacity. Here, we determined the immunosuppressive capacity of digoxin on the development of experimental autoimmune uveitis (EAU) and on related immune responses. Methods The B10.A mice were immunized with interphotoreceptor retinoid-binding protein (IRBP) and were treated daily with digoxin or vehicle control. On postimmunization day 14, the mouse eyes were examined histologically, while spleen cells were tested for cytokine production in response to IRBP and purified protein derivative. The immunosuppressive activity of digoxin was also tested in vitro, by its capacity to inhibit development of Th1 or Th17 cells. To investigate the degenerative effect of digoxin on the retina, naïve (FVB/N × B10.BR)F1 mice were similarly treated with digoxin and tested histologically and by ERG. Results Treatment with digoxin inhibited the development of EAU, as well as the cellular response to IRBP. Unexpectedly, treatment with digoxin suppressed the production of interferon-γ to a larger extent than the production of interleukin 17. Importantly, digoxin treatment induced severe retinal degeneration, determined by histologic analysis with thinning across all layers of the retina. Digoxin treatment also induced dose-dependent vision loss monitored by ERG on naïve mice without induction of EAU. Conclusions Treatment of mice with digoxin inhibited the development of EAU and cellular immune response to IRBP. However, the treatment induced severe damage to the retina. Thus, the use of digoxin in humans should be avoided due to its toxicity to the retina. PMID:27028065

  2. Global specialized stroke care delivery models.

    PubMed

    Theofanidis, Dimitrios; Savopoulos, Christos; Hatzitolios, Apostolos

    2016-03-01

    Stroke services still vary enormously from country to country, with many countries providing no special services at all. The aim of this article is to provide a concise overview of the various types of acute stroke delivery systems at present available and critically describe merits and shortcomings. A systematic literature review was undertaken from 1990 to July 2014. Several models for stroke services have been developed mostly in the past 3 decades, mainly in the Western world. These include state-of-the-art stroke services ranging from highly specialized stroke centers to mobile stroke units for the community. In this light, the recommendations of the structure and organization of stroke units and stroke centers by the European Stroke Organization were recently published. What differentiates the various models of stroke care delivery across the globe is the diversity of services ranging from low key conventional care to highly sophisticated facilities with life saving interventional features via integrated stroke care infrastructure. Effective in-hospital care for stroke should start in the emergency department where a swift and appropriate diagnosis should be made. The role of all brain neuroimaging procedures should have a defined a priori and proper demarcation between actions according to updated stroke care pathways and clinical protocols, which should be followed closely. These essential actions initiated by well-trained staff in the emergency department, should then be carried on in dedicated stroke facilities that is, a stroke unit.

  3. Google Calendar: A single case experimental design study of a man with severe memory problems.

    PubMed

    Baldwin, Victoria N; Powell, Theresa

    2015-01-01

    A single case experimental design across behaviours was utilised to explore the effectiveness of Google Calendar text alerts delivered to a mobile phone as a memory aid. The participant was a 43-year-old man (JA) with severe memory problems and executive difficulties caused by a traumatic brain injury (TBI). JA was initially very unwilling to use any memory aid and so a detailed assessment of his beliefs about memory aids, his cognitive difficulties and his social context was performed and a set of specifications for an aid was produced collaboratively. Six weeks of baseline data and six weeks of intervention data were collected for three target memory behaviours and three control memory behaviours. Results were analysed using nonoverlap of all pairs (NAP) analysis which showed a reduction in forgetting in the three target behaviours and no change in two of the three control behaviours. A subjective measure (the revised Everyday Memory Questionnaire) also suggested improvement. This study illustrates that Google Calendar is a highly effective memory aid and emphasises the importance of choosing a memory aid to suit the person's lifestyle and beliefs.

  4. Luteinizing hormone secretion in hemidecorticate female rats under several experimental conditions.

    PubMed

    Fernandes, G A; Antunes-Rodrigues, J; Covian, M R

    1978-01-01

    Luteinizing hormone (LH) secretion by the anterior pituitary gland was investigated in hemidecorticate (HD) rats under several conditions. Higher plasma and lower pituitary LH levels were observed in HD rats in the afternoon of proestrus, after unilateral ovariectomy, and at the 7th and 14th days after bilateral castration. The ovarian hypertrophy observed in HD rats did not differ from control. When hormonal substitutive therapy was started 3 days after bilateral ovariectomy, larger doses of estradiol benzoate (EB) were required to reduce plasma LH levels in control than in HD animals. The increase in pituitary weight was, however, significantly higher in the HD castrated group. When substitutive therapy started at the 7th and 14th days after castration no significant differences between the 2 experimental groups were observed. The results of substitutive therapy suggest that hemidecortication induces an increase in the sensitivity of hypothalamic-pituitary axis to estrogen negative feedback. This change in sensitivity is clearly seen in HD rats during the first few days after castration. These results suggest that hemidecortication may release the hypothalamus from inhibitory influences coming from rhinencephalic or cortical structures, thus rendering the preoptic-suprachiasmatic complex (POA-SCH) more sensitive to LH-releasing mechanisms.

  5. An Experimental Investigation of Several Low-Drag Wing-Nacelle Combinations with Internal Air Flow

    NASA Technical Reports Server (NTRS)

    Allen, H. Julian; Frick, Charles W.; Erickson, Myles D.

    1945-01-01

    The results of an experimental investigation of several low-drag wing-nacelle combinations, incorporating internal air-flow systems, are presented. The external-drag increments due to these nacelles are between one-half and two-thirds of those of conventional nacelle forms. This improvement is accomplished with only minor effects on the lift and moment characteristics of the wing. The procedure employed to determine the external shape of such low-drag nacelles is considered in detail. The design of an efficient internal-flow system with or without a blower or throttle, presents no serious problems. The energy losses in the expansion before the engine and the contraction thereafter can be kept small. It is believed that these nacelles have a wide application in housing engine pusher-propeller units and, with some alteration, jet-propulsion devices. It is probable that the low external drags may not be realized if such nacelles are used with a tractor propeller because of the high level of turbulence in the propeller slipstream.

  6. Recovering after stroke

    MedlinePlus

    Stroke rehabilitation; Cerebrovascular accident - rehabilitation; Recovery from stroke; Stroke - recovery; CVA - recovery ... LIVE AFTER A STROKE Most people will need stroke rehabilitation (rehab) to help them recover after they leave ...

  7. Stroke Warning Signs

    MedlinePlus

    ... News Advocate Stroke Warning Signs Quiz Stroke Warning Signs and Symptoms THINK YOU ARE HAVING A STROKE? ... Learn more stroke signs and symptoms >>>> Stroke Warning Signs Hip-Hop F.A.S.T. Video Updated Guidelines ...

  8. An Experimental and Computational Study of Windborne Debris in Severe Storms

    NASA Astrophysics Data System (ADS)

    Karimpour, Arash

    This research focuses on an experimental and theoretical investigation of windborne debris emanating from loose gravel on built-up roofs. During severe storms, windborne debris can cause considerable physical harm and property damage. One of the major sources of flying debris in large commercial areas is loose gravel on built-up roofs. Such loose gravel can be responsible loss of life and significant property damage. Despite the high risk of windborne debris, their flight mechanics are poorly understood. To better understand windborne debris flight, a series of experiments were conducted in the Clemson University Boundary Layer Wind Tunnel. These experiments were designed to quantify the conditions under which gravel became airborne, the rate at which it was removed, and the resulting flight distance of the debris. In order to conduct experiments in the Boundary Layer Wind Tunnel it is important to understand how to model the atmospheric boundary layer (ABL). A new curve fitting method is presented for calculating the ABL logarithmic velocity profile parameters i.e. shear velocity, surface roughness and zero plane displacement. The new method uses only the time averaged velocity profile and requires no iteration. Comparison with existing methods shows that the new approach has equal or better accuracy than existing curve fitting and geometric approaches with fewer calculation steps. Debris flight is a highly stochastic process with uncertainty and variability in the debris particle the turbulent wind field. However, current models are almost entirely deterministic. A series of Monte Carlo simulations based on existing debris flight equations were run to quantify the impact if input uncertainty on flight outcome (flight distance and impact kinetic energy). Results indicate that failure to account for parameter variability will result in under predicting the mean flight distance and kinetic energy, and ignoring outcome variability / uncertainty. A full quantification

  9. Ischemic Stroke.

    PubMed

    Capriotti, Teri; Murphy, Teresa

    2016-05-01

    Each year, more than 795,000 people in the United States suffer a stroke and by 2030, it is estimated that 4% of the U.S. population will have had a stroke. Home healthcare clinicians will be increasingly called upon to assist stroke survivors and their caregivers adjust to disability and assist the survivor during their reintegration into the community. Therapeutic modalities are changing with advanced technology. Great strides are being made in the treatment of acute stroke; particularly endovascular interventions. More patients are surviving the acute stroke event and therefore will need to learn how to live with various degrees of disability. It is important for home healthcare clinicians to understand the process from acute event to medical stabilization, and from rehabilitation to long-term adaptation.

  10. Ischemic Stroke.

    PubMed

    Capriotti, Teri; Murphy, Teresa

    2016-05-01

    Each year, more than 795,000 people in the United States suffer a stroke and by 2030, it is estimated that 4% of the U.S. population will have had a stroke. Home healthcare clinicians will be increasingly called upon to assist stroke survivors and their caregivers adjust to disability and assist the survivor during their reintegration into the community. Therapeutic modalities are changing with advanced technology. Great strides are being made in the treatment of acute stroke; particularly endovascular interventions. More patients are surviving the acute stroke event and therefore will need to learn how to live with various degrees of disability. It is important for home healthcare clinicians to understand the process from acute event to medical stabilization, and from rehabilitation to long-term adaptation. PMID:27145407

  11. Maternal Deprivation of Lewis Rat Pups Increases the Severity of Experi-mental Periodontitis in Adulthood

    PubMed Central

    Breivik, Torbjørn; Gundersen, Yngvar; Murison, Robert; Turner, Jonathan D; Muller, Claude P; Gjermo, Per; Opstad, Kristian

    2015-01-01

    Background and Objective: Early life adverse events may influence susceptibility/resistance to chronic inflammatory diseases later in life by permanently dysregulating brain-controlled immune-regulatory systems. We have investigated the impact of infant-mother separation during early postnatal life on the severity of experimental periodontitis, as well as systemic stress and immune responses, in adulthood. Material and Methods: Pups of periodontitis resistant Lewis rats were separated from their mothers for 3 h daily during postnatal days 2-14 (termed maternal deprivation; MD), separated for 15 min daily during the same time period (termed handling; HD), or left undisturbed. As adults, their behaviour was tested in a novel stressful situation, and ligature-induced periodontitis applied for 21 days. Two h before sacrifice all rats were exposed to a gram-negative bacterial lipopolysaccharide (LPS) challenge to induce a robust immune and stress response. Results: Compared to undisturbed controls, MD rats developed significantly more periodontal bone loss as adults, whereas HD rats showed a tendency to less disease. MD and HD rats exhibited depression-like behaviour in a novel open field test, while MD rats showed higher glucocorticoid receptor (Gr) expression in the hippocampus, and HD rats had altered methylation of genes involved in the expression of hippocampal Gr. LPS provoked a significantly lower increase in circulating levels of the cytokine TGF-1β in MD and HD rats, but there were no significant differences in levels of the stress hormone corticosterone. Conclusion: Stressful environmental exposures in very early life may alter immune responses in a manner that influences susceptibility/resistance to periodontitis. PMID:25713634

  12. Neuropsychology of acute stroke.

    PubMed

    Sinanović, Osman

    2010-06-01

    several cross-sectional studies, peaking three to six months after a stroke.

  13. Stroke and Native Hawaiians/Pacific Islanders

    MedlinePlus

    ... Other Pacific Islander > Stroke Stroke and Native Hawaiians/Pacific Islanders Native Hawaiians/Pacific Islanders were four times more likely than non- ... a stroke in 2010. In general, Native Hawaiian/Pacific Islander adults have developed several of the high ...

  14. Stroke pharmacogenomics.

    PubMed

    Billeci, Antonia M R; Agnelli, Giancarlo; Caso, Valeria

    2009-12-01

    Circulatory disease accounts for fifteen million deaths each year, of which stroke accounts for four and a half million- with an estimated nine million stroke survivors annually. The overall incidence rate of stroke is 2 to 2.5 per thousand adults with an approximate prevalence of 5 per thousand and an estimated 5-year risk of stroke recurrence of 15 to 40 percent. Conventional risk factors for stroke include: increasing age, hypertension, diabetes mellitus, smoking, increased body mass index, ischemic heart disease, heart failure, atrial fibrillation and lack of physical activity. Age is the strongest risk factor for both ischemic and haemorrhagic stroke with its incidence doubling for each successive decade after the age of fifty-five years. However, there is a substantial portion of patients with significant cerebrovascular disease who do not have any of these stroke risk-factors, leading to the speculation that there are other factors that have not been identified yet So as to improve diagnosis and treatment strategies, as well as to reduce the related public health burden, it could be helpful to successfully identify its extremely complex genetic determinants (polygenic, multiple genes play a role). Pharmacogenetics is the field of pharmacology that deals with the influence of genetic variation on drug response by correlating gene expression and gene variants with the efficacy or toxicity of drugs. The principle drugs in stroke medicine are antithrombotics. The aim of this paper was to review the most commonly used drugs for stroke such as rtPA in the acute phase as well as antiplatelets and wafarin for secondary prophylaxis. PMID:19925046

  15. Neuroprotective effect of naringenin is mediated through suppression of NF-κB signaling pathway in experimental stroke.

    PubMed

    Raza, S S; Khan, M M; Ahmad, A; Ashafaq, M; Islam, F; Wagner, A P; Safhi, M M; Islam, F

    2013-01-29

    Oxidative stress and inflammation play an integral role in the pathogenesis of cerebral ischemia that leads to a cascade of events culminating in the death of neurons and their supporting structures. The signaling pathways that link these events are not fully understood. Recent studies have demonstrated a close link between the nuclear factor-κB (NF-κB) signaling pathway and cerebral ischemia/reperfusion (I/R)-induced inflammation. Flavonoids have been suggested to exert human health benefits by anti-oxidant and anti-inflammatory mechanisms. In this study we undertook a pharmacological approach to investigate the ability of naringenin, a potent flavonoid, to prevent oxidative stress and NF-κB-mediated inflammatory brain damage in the rat model of focal cerebral I/R injury. To test this hypothesis, male Wistar rats were pretreated with naringenin once daily for 21 days and then subjected to 1h of middle cerebral artery occlusion followed by 23 h of reperfusion. Naringenin treatment successfully upregulates the antioxidant status, decreases the infarct size and lowers the levels of myeloperoxidase, nitric oxide and cytokines, besides functional recovery returned close to the baseline. Moreover, immunohistochemical and Western blot analyses clearly demonstrated that naringenin treatment limits glial activation and downregulates the NF-κB expression level and their target genes. These results show, prophylactic treatment with naringenin improved functional outcomes and abrogated the ischemic brain injury by suppressing NF-κB-mediated neuroinflammation. The present study suggests that naringenin may be used as a potential neuroprotectant in patients at high risk of ischemic stroke. PMID:23103795

  16. Stroke and the female brain.

    PubMed

    Bushnell, Cheryl D

    2008-01-01

    Stroke is a major public health problem. The female population carries a higher stroke burden than the male population, both because females have a longer life expectancy and because most stroke deaths occur in women. Differences between the sexes in relation to stroke are increasingly being recognized; for example, among stroke survivors, women tend to have worse outcomes than men, as indicated by more-severe disability and an increased likelihood of institutionalization in women. Women and men with stroke also differ in their risk factor profiles, and they respond differently to primary-prevention and acute stroke treatment. Women experience variations in endogenous estrogens throughout their life cycle and might also be exposed to exogenous estrogens, both of which markedly affect the brain. An understanding of the effects of endogenous and exogenous estrogens on cerebral hemodynamics could guide research into explaining how hormone therapy increases the risk of stroke in postmenopausal women. This Review summarizes the sex differences related to stroke, and the effect of endogenous and exogenous hormones on the cerebrovasculature of the female brain. It also proposes potential research approaches, the results of which could fill in gaps in our knowledge regarding the mechanism of action of estrogen in the brain.

  17. Stroke - risk factors

    MedlinePlus

    Preventing stroke; Stroke - prevention; CVA - prevention; TIA - prevention ... Biology; Council on Hypertension. Guidelines for the primary prevention of stroke: a statement for healthcare professionals from ...

  18. Stroke Treatments

    MedlinePlus

    ... weakened blood vessels that also cause hemorrhagic stroke: aneurysms and arteriovenous malformations (AVMs). Treatment differs depending on ... the leg or arm, then guided to the aneurysm or AVM ; it then deposits a mechanical agent, ...

  19. Severity of chronic experimental Chagas' heart disease parallels tumour necrosis factor and nitric oxide levels in the serum: models of mild and severe disease

    PubMed Central

    Pereira, Isabela Resende; Vilar-Pereira, Glaucia; da Silva, Andrea Alice; Lannes-Vieira, Joseli

    2014-01-01

    Heart tissue inflammation, progressive fibrosis and electrocardiographic alterations occur in approximately 30% of patients infected by Trypanosoma cruzi, 10-30 years after infection. Further, plasma levels of tumour necrosis factor (TNF) and nitric oxide (NO) are associated with the degree of heart dysfunction in chronic chagasic cardiomyopathy (CCC). Thus, our aim was to establish experimental models that mimic a range of parasitological, pathological and cardiac alterations described in patients with chronic Chagas’ heart disease and evaluate whether heart disease severity was associated with increased TNF and NO levels in the serum. Our results show that C3H/He mice chronically infected with the Colombian T. cruzi strain have more severe cardiac parasitism and inflammation than C57BL/6 mice. In addition, connexin 43 disorganisation and fibronectin deposition in the heart tissue, increased levels of creatine kinase cardiac MB isoenzyme activity in the serum and more severe electrical abnormalities were observed in T. cruzi-infected C3H/He mice compared to C57BL/6 mice. Therefore, T. cruzi-infected C3H/He and C57BL/6 mice represent severe and mild models of CCC, respectively. Moreover, the CCC severity paralleled the TNF and NO levels in the serum. Therefore, these models are appropriate for studying the pathophysiology and biomarkers of CCC progression, as well as for testing therapeutic agents for patients with Chagas’ heart disease. PMID:24937048

  20. [Reducing the burden of stroke in Israel].

    PubMed

    Tanne, David; Goldbourt, Uri

    2008-11-01

    Stroke is the third most common cause of death in Israel. Stroke is a leading cause of severe long-term disability and is associated with staggering economic costs. Ethnic variations observed in stroke mortality rates support that undetermined inherent genetic or sociocultural differences act to increase stroke mortality rates in immigrants from Asia and North Africa over that predicted from their profile of traditional risk factors. In accordance with other Western countries, there has been a decline in mortality rates from stroke, concomitantly with a decline observed in coronary heart disease mortality. With the aging of the population, the burden of stroke is projected to further increase. Moreover, brain infarcts detected by brain imaging are 5-times more common than the clinical syndrome of acute stroke, detected in about 20% of healthy elderly and up to 50% of high risk patients. Estimates of the incidence of stroke, characteristics of patients, management and outcome became available from the tri-annual national acute stroke Israeli survey (NASIS) program, initiated during 2004. The annual incidence of hospitalized acute cerebrovascular events is approximately 13,000 and rates, particularly in women, seem even higher than those observed for acute myocardial infarction. Findings also highlight critical deficiencies in acute stroke units and systems for urgent evaluation and intervention in acute stroke. Action plans are urgently required, in accordance with the experience from other countries, in order to upgrade the stroke infrastructure nationwide for more effective prevention and management of acute stroke.

  1. Clinical study of 222 patients with pure motor stroke.

    PubMed

    Arboix, A; Padilla, I; Massons, J; García-Eroles, L; Comes, E; Targa, C

    2001-08-01

    The objective was to assess the frequency of pure motor stroke caused by different stroke subtypes and to compare demographic, clinical, neuroimaging, and outcome data of pure motor stroke with those of patients with other lacunar stroke as well as with those of patients with non-lacunar stroke. Data from 2000 patients with acute stroke (n=1761) or transient ischaemic attack (n=239) admitted consecutively to the department of neurology of an acute care 350 bed teaching hospital were prospectively collected in the Sagrat Cor Hospital of Barcelona stroke registry over a 10 year period. For the purpose of the study 222 (12.7%) patients with pure motor stroke were selected. The other study groups included 218 (12.3%) patients with other lacunar strokes and 1321 (75%) patients with non-lacunar stroke. In relation to stroke subtype, lacunar infarcts were found in 189 (85%) patients, whereas ischaemic lacunar syndromes not due to lacunar infarcts occurred in 23 (10.4%) patients (atherothrombotic stroke in 12, cardioembolic stroke in seven, infarction of undetermined origin in three, and infarction of unusual aetiology in one) and haemorrhagic lacunar syndromes in 10 (4.5%). Patients with pure motor stroke showed a better outcome than patients with non-lacunar stroke with a significantly lower number of complications and in hospital mortality rate, shorter duration of hospital stay, and a higher number of symptom free patients at hospital discharge. After multivariate analysis, hypertension, diabetes, obesity, hyperlipidaemia, non-sudden stroke onset, internal capsule involvement, and pons topography seemed to be independent factors of pure motor stroke in patients with acute stroke. In conclusion, about one of every 10 patients with acute stroke had a pure motor stroke. Pure motor stroke was caused by a lacunar infarct in 85% of patients and by other stroke subtypes in 15%. Several clinical features are more frequent in patients with pure motor stroke than in patients

  2. Rhodococcus equi hyperimmune plasma decreases pneumonia severity after a randomised experimental challenge of neonatal foals.

    PubMed

    Sanz, M G; Loynachan, A; Horohov, D W

    2016-03-12

    Since a vaccine is not available against Rhodococcus equi, R equi-specific hyperimmune plasma (HIP) is commonly used, although its efficacy remains controversial. The objective of this study was to evaluate the ability of a commercially available HIP to prevent clinical rhodococcal pneumonia in neonatal foals after experimental challenge. PMID:26932206

  3. Healthy Living after Stroke

    MedlinePlus

    ... After Stroke Weight Training After Stroke Tips for Improving Fine Motor Skills Functional Tone Management Arm Training Program Constraint-Induced Movement Therapy Emotional & Behavioral Challenges Self-Esteem after Stroke Post-Stroke Mood Disorders One-side ...

  4. On the construction of experimental designs for a given task by jointly optimizing several quality criteria: Pareto-optimal experimental designs.

    PubMed

    Sánchez, M S; Sarabia, L A; Ortiz, M C

    2012-11-19

    Experimental designs for a given task should be selected on the base of the problem being solved and of some criteria that measure their quality. There are several such criteria because there are several aspects to be taken into account when making a choice. The most used criteria are probably the so-called alphabetical optimality criteria (for example, the A-, E-, and D-criteria related to the joint estimation of the coefficients, or the I- and G-criteria related to the prediction variance). Selecting a proper design to solve a problem implies finding a balance among these several criteria that measure the performance of the design in different aspects. Technically this is a problem of multi-criteria optimization, which can be tackled from different views. The approach presented here addresses the problem in its real vector nature, so that ad hoc experimental designs are generated with an algorithm based on evolutionary algorithms to find the Pareto-optimal front. There is not theoretical limit to the number of criteria that can be studied and, contrary to other approaches, no just one experimental design is computed but a set of experimental designs all of them with the property of being Pareto-optimal in the criteria needed by the user. Besides, the use of an evolutionary algorithm makes it possible to search in both continuous and discrete domains and avoid the need of having a set of candidate points, usual in exchange algorithms.

  5. Review of Experimental Research on Academic Learning by Students with Moderate and Severe Intellectual Disability in General Education

    ERIC Educational Resources Information Center

    Hudson, Melissa E.; Browder, Diane M.; Wood, Leah A.

    2013-01-01

    A review of the literature on academic learning in general education settings for students with moderate and severe intellectual disability was conducted. A total of 17 experimental studies was identified and evaluated using quality indicators for single-case design research. Studies that met or met with reservation the criteria established for…

  6. A Novel Chemically Modified Curcumin Reduces Severity of Experimental Periodontal Disease in Rats: Initial Observations

    PubMed Central

    Elburki, Muna S.; Rossa, Carlos; Guimaraes, Morgana R.; Goodenough, Mark; Lee, Hsi-Ming; Curylofo, Fabiana A.; Zhang, Yu; Johnson, Francis; Golub, Lorne M.

    2014-01-01

    Tetracycline-based matrix metalloproteinase- (MMP-) inhibitors are currently approved for two inflammatory diseases, periodontitis and rosacea. The current study addresses the therapeutic potential of a novel pleiotropic MMP-inhibitor not based on an antibiotic. To induce experimental periodontitis, endotoxin (LPS) was repeatedly injected into the gingiva of rats on one side of the maxilla; the contralateral (control) side received saline injections. Two groups of rats were treated by daily oral intubation with a chemically modified curcumin, CMC 2.24, for two weeks; the control groups received vehicle alone. After sacrifice, gingiva, blood, and maxilla were collected, the jaws were defleshed, and periodontal (alveolar) bone loss was quantified morphometrically and by μ-CT scan. The gingivae were pooled per experimental group, extracted, and analyzed for MMPs (gelatin zymography; western blot) and for cytokines (e.g., IL-1β; ELISA); serum and plasma samples were analyzed for cytokines and MMP-8. The LPS-induced pathologically excessive bone loss was reduced to normal levels based on either morphometric (P = 0.003) or μ-CT (P = 0.008) analysis. A similar response was seen for MMPs and cytokines in the gingiva and blood. This initial study, on a novel triketonic zinc-binding CMC, indicates potential efficacy on inflammatory mediators and alveolar bone loss in experimental periodontitis and warrants future therapeutic and pharmacokinetic investigations. PMID:25104884

  7. [Heat stroke. Standarized treatment plan].

    PubMed

    García-Velasco Sánchez-Morago, Santiago; Monzón Ferrer, Adrián

    2008-05-01

    Heat stroke, or sun stroke, is defined as an emergency situation characterized by an increase in central body temperature above 40 degrees C and alterations in the central nervous system where encephalopathy predominates and coma is typical. A precocious diagnosis is essential and if the initial opportune measures are not taken, the death rate is very high, up to 70%. Due to climate changes, the number of heat stroke cases has increased since the 2003 heat wave. Although at first symptoms these cases are treated in hospital emergency wards or outpatient wards, when the severity of a person stricken by heat stroke becomes life-threatening or advanced medical care is warranted, patients are placed in Intensive Medical Care Wards. Even though cases of heat stroke are low, its lethalness converts it to a serious life-threatening circumstance due to thermal regulation deterioration, adverse neurological effects, and secondary multi-organ dysfunction.

  8. Experimental study and analysis of lubricants dispersed with nano Cu and TiO2 in a four-stroke two wheeler

    PubMed Central

    2011-01-01

    The present investigation summarizes detailed experimental studies with standard lubricants of commercial quality known as Racer-4 of Hindustan Petroleum Corporation (India) dispersed with different mass concentrations of nanoparticles of Cu and TiO2. The test bench is fabricated with a four-stroke Hero-Honda motorbike hydraulically loaded at the rear wheel with proper instrumentation to record the fuel consumption, the load on the rear wheel, and the linear velocity. The whole range of data obtained on a stationery bike is subjected to regression analysis to arrive at various relationships between fuel consumption as a function of brake power, linear velocity, and percentage mass concentration of nanoparticles in the lubricant. The empirical relation correlates with the observed data with reasonable accuracy. Further, extension of the analysis by developing a mathematical model has revealed a definite improvement in brake thermal efficiency which ultimately affects the fuel economy by diminishing frictional power in the system with the introduction of nanoparticles into the lubricant. The performance of the engine seems to be better with nano Cu-Racer-4 combination than the one with nano TiO2. PMID:21711765

  9. Experimental study and analysis of lubricants dispersed with nano Cu and TiO2 in a four-stroke two wheeler

    NASA Astrophysics Data System (ADS)

    Sarma, Pullela K.; Srinivas, Vadapalli; Rao, Vedula Dharma; Kumar, Ayyagari Kiran

    2011-12-01

    The present investigation summarizes detailed experimental studies with standard lubricants of commercial quality known as Racer-4 of Hindustan Petroleum Corporation (India) dispersed with different mass concentrations of nanoparticles of Cu and TiO2. The test bench is fabricated with a four-stroke Hero-Honda motorbike hydraulically loaded at the rear wheel with proper instrumentation to record the fuel consumption, the load on the rear wheel, and the linear velocity. The whole range of data obtained on a stationery bike is subjected to regression analysis to arrive at various relationships between fuel consumption as a function of brake power, linear velocity, and percentage mass concentration of nanoparticles in the lubricant. The empirical relation correlates with the observed data with reasonable accuracy. Further, extension of the analysis by developing a mathematical model has revealed a definite improvement in brake thermal efficiency which ultimately affects the fuel economy by diminishing frictional power in the system with the introduction of nanoparticles into the lubricant. The performance of the engine seems to be better with nano Cu-Racer-4 combination than the one with nano TiO2.

  10. Experimental study and analysis of lubricants dispersed with nano Cu and TiO2 in a four-stroke two wheeler.

    PubMed

    Sarma, Pullela K; Srinivas, Vadapalli; Rao, Vedula Dharma; Kumar, Ayyagari Kiran

    2011-01-01

    The present investigation summarizes detailed experimental studies with standard lubricants of commercial quality known as Racer-4 of Hindustan Petroleum Corporation (India) dispersed with different mass concentrations of nanoparticles of Cu and TiO2. The test bench is fabricated with a four-stroke Hero-Honda motorbike hydraulically loaded at the rear wheel with proper instrumentation to record the fuel consumption, the load on the rear wheel, and the linear velocity. The whole range of data obtained on a stationery bike is subjected to regression analysis to arrive at various relationships between fuel consumption as a function of brake power, linear velocity, and percentage mass concentration of nanoparticles in the lubricant. The empirical relation correlates with the observed data with reasonable accuracy. Further, extension of the analysis by developing a mathematical model has revealed a definite improvement in brake thermal efficiency which ultimately affects the fuel economy by diminishing frictional power in the system with the introduction of nanoparticles into the lubricant. The performance of the engine seems to be better with nano Cu-Racer-4 combination than the one with nano TiO2. PMID:21711765

  11. Misconduct in the Prosecution of Severe Crimes: Theory and Experimental Test

    ERIC Educational Resources Information Center

    Lucas, Jeffrey W.; Graif, Corina; Lovaglia, Michael J.

    2006-01-01

    Prosecutorial misconduct involves the intentional use of illegal or improper methods for attaining convictions against defendants in criminal trials. Previous research documented extensive errors in the prosecution of severe crimes. A theory formulated to explain this phenomenon proposes that in serious cases, increased pressure to convict…

  12. Role of social factors on cell death, cerebral plasticity and recovery after stroke.

    PubMed

    Venna, Venugopal Reddy; McCullough, Louise D

    2015-04-01

    Stroke is a serious global health care problem. It is now is the fourth leading cause of death and the primary cause of adult disability in the United States. Substantial evidence from both experimental and clinical studies has demonstrated that social isolation (SI) can increase stroke incidence and impair recovery. Epidemiological studies demonstrate that an increasing number of patients are living alone, and as the aging population increases, loneliness will only increase in prevalence. SI is increasingly identified as an independent risk factor for all-cause mortality. In contrast, individuals with high levels of social support exhibit more rapid and extensive functional and cognitive recovery after a wide variety of pathological insults, including stroke. Clinical data suggests that SI is an important risk factor for increased mortality and delayed functional recovery following ischemic stroke. Attesting to the importance of mortality and behavioral factors in stroke outcome is that these same effects can be reproduced in animal models of experimental stroke. This has allowed researchers to identify several mechanistic changes that occur with affiliative interactions. These include decreased systemic inflammation, elaboration of growth factors including brain derived neurotropic factor (BDNF), enhanced neurogenesis, and improved neuroimmune responsiveness in group housed animals. These may mediate the beneficial effects of social interaction on improving stroke recovery and reducing neuronal death. In this review we provide an overview of the effects of SI on ischemic injury and recovery and discuss their clinical and therapeutic implications.

  13. Stroke and episodic memory disorders.

    PubMed

    Lim, Chun; Alexander, Michael P

    2009-12-01

    Memory impairments are common after stroke, and the anatomical basis for impairments may be quite variable. To determine the range of stroke-related memory impairment, we identified all case reports and group studies through the Medline database and the Science Citation Index. There is no hypothesis about memory that is unique to stroke, but there are several important facets of memory impairment after stroke: (1) Every node of the limbic system implicated in memory may be damaged by stroke but very rarely in isolation and the combination of amnesia with the associated deficits often illuminates additional aspects of memory functions. (2) Stroke produces amnesia by damage to critical convergence white matter connections of the limbic system, and stroke is the only etiology of amnesia that can delineate the entire pathway of memory and critical convergence points. (3) Stroke also impairs memory, without causing classical amnesia, by damaging brain regions responsible for cognitive processes, some modality specific and some more generally strategic, that are essential for normal learning and recall.

  14. [Experimental studies on the antimicrobial effect of several butylcyanoacrylate tissue adhesives].

    PubMed

    Uhlig, R; Gitt, H A; Wildführ, W

    1978-01-01

    It is dealt with the effects of various butycyano-acrylate type surgical adhesives on gram-positive and gram-negative bacterial species. The experimental results show a growth-inhibiting effect on gram-positive germs. Gram-negative germs are not affected. The growth inhibition produced by SO2-containing adhesives is greater than that caused by SO2-free ones. As compared to Histoacryl blue, the Fimomed variants showed a broader spectrum. Furthermore, it was stated that the adhesive exerts its growth-inhibiting effect not only in the monomeric, but also in the polymeric state. A relationship between the gram-behaviour and the antimicrobic effect of the adhesive is taken into consideration.

  15. Several experimental realizations of symmetric phase-covariant quantum cloners of single-photon qubits

    NASA Astrophysics Data System (ADS)

    Soubusta, Jan; Bartůšková, Lucie; Černoch, Antonín; Fiurášek, Jaromír; Dušek, Miloslav

    2007-10-01

    We compare several optical implementations of phase-covariant cloning machines. The experiments are based on copying of the polarization state of a single photon in bulk optics by a special unbalanced beam splitter or by a balanced beam splitter accompanied by a state filtering. Also the all-fiber-based setup is discussed, where the information is encoded into spatial modes, i.e., the photon can propagate through two optical fibers. Each of the four implementations possesses some advantages and disadvantages that are discussed.

  16. Several experimental realizations of symmetric phase-covariant quantum cloners of single-photon qubits

    SciTech Connect

    Soubusta, Jan; Cernoch, Antonin; Bartuskova, Lucie; Fiurasek, Jaromir; Dusek, Miloslav

    2007-10-15

    We compare several optical implementations of phase-covariant cloning machines. The experiments are based on copying of the polarization state of a single photon in bulk optics by a special unbalanced beam splitter or by a balanced beam splitter accompanied by a state filtering. Also the all-fiber-based setup is discussed, where the information is encoded into spatial modes, i.e., the photon can propagate through two optical fibers. Each of the four implementations possesses some advantages and disadvantages that are discussed.

  17. Enkephalins and hormonal-metabolic reactions in experimental stress depending on its severity

    SciTech Connect

    Lishmanov, Y.B.; Alekminskaya, L.A.; Lasukova, T.V.

    1985-08-01

    The aim of this investigation was to study the action of enkephalins on changes in hormonal-metabolic constants in stress of varied severity. Catecholamine excretion with the urine was determined fluorometrically, serum cortisol and insulin concentrations were measured radioimmunologically and glucose was determined by the standard orthotoluidine method. The results of the investigation indicate that enkephalins have a modulating effect on various hormonal mechanisms of adaptation stress. The results confirm that the physiological action of the peptide regulator depends on the functional state of the biological systems and it may differ sharply, even to the extent of diametrically opposite effects.

  18. Allopurinol reduces severity of delayed neurologic sequelae in experimental carbon monoxide toxicity in rats.

    PubMed

    Dong, Guangtao; Ren, Ming; Wang, Xiujie; Jiang, Hongquan; Yin, Xiang; Wang, Shuyu; Wang, Xudong; Feng, Honglin

    2015-05-01

    Approximately half of those who survive severe carbon monoxide (CO) poisoning develop delayed neurologic sequelae. Growing evidence supports the crucial role of free radicals in delayed brain injury associated with CO toxicity. Xanthine oxidase (XO) has been reported to play a pivotal role in the generation of reactive oxygen species (ROS) in CO poisoning. A recent report indicates that allopurinol both attenuated oxidative stress and possessed anti-inflammatory properties in an animal model of acute liver failure. In this study, we aimed to explore the potential of allopurinol to reduce the severity of delayed neurologic sequelae. The rats were first exposed to 1000 ppm CO for 40 min and then to 3000 ppm CO for another 20 min. Following CO poisoning, the rats were injected with allopurinol (50 mg/kg, i.p.) six times. Results showed that allopurinol significantly reduced neuronal death and suppressed expression of pro-inflammatory factors, including tumor necrosis factor-α, intercellular adhesion molecule-1, ionized calcium-binding adapter molecule 1, and degraded myelin basic protein. Furthermore, behavioral studies revealed an improved performance in the Morris water maze test. Our findings indicated that allopurinol may have protective effects against delayed neurologic sequelae caused by CO toxicity.

  19. Genetic susceptibility to ischemic stroke

    PubMed Central

    Meschia, James F.; Worrall, Bradford B.; Rich, Stephen S.

    2014-01-01

    Clinicians who treat patients with stroke need to be aware of several single-gene disorders that have ischemic stroke as a major feature, including sickle cell disease, Fabry disease, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, and retinal vasculopathy with cerebral leukodystrophy. The reported genome-wide association studies of ischemic stroke and several related phenotypes (for example, ischemic white matter disease) have shown that no single common genetic variant imparts major risk. Larger studies with samples numbering in the thousands are ongoing to identify common variants with smaller effects on risk. Pharmacogenomic studies have uncovered genetic determinants of response to warfarin, statins and clopidogrel. Despite increasing knowledge of stroke genetics, incorporating this new knowledge into clinical practice remains a challenge. The goals of this article are to review common single-gene disorders relevant to ischemic stroke, summarize the status of candidate gene and genome-wide studies aimed at discovering genetic stroke risk factors, and to briefly discuss pharmacogenomics related to stroke treatment. PMID:21629240

  20. Gestational Hypothyroidism Increases the Severity of Experimental Autoimmune Encephalomyelitis in Adult Offspring

    PubMed Central

    Albornoz, Eduardo A.; Carreño, Leandro J.; Cortes, Claudia M.; Gonzalez, Pablo A.; Cisternas, Pablo A.; Cautivo, Kelly M.; Catalán, Tamara P.; Opazo, M. Cecilia; Eugenin, Eliseo A.; Berman, Joan W.; Bueno, Susan M.; Kalergis, Alexis M.

    2013-01-01

    Background: Maternal thyroid hormones play a fundamental role in appropriate fetal development during gestation. Offspring that have been gestated under maternal hypothyroidism suffer cognitive impairment. Thyroid hormone deficiency during gestation can significantly impact the central nervous system by altering the migration, differentiation, and function of neurons, oligodendrocytes, and astrocytes. Given that gestational hypothyroidism alters the immune cell ratio in offspring, it is possible that this condition could result in higher sensitivity for the development of autoimmune diseases. Methods: Adult mice gestated under hypothyroidism were induced with experimental autoimmune encephalomyelitis (EAE). Twenty-one days after EAE induction, the disease score, myelin content, immune cell infiltration, and oligodendrocyte death were evaluated. Results: We observed that mice gestated under hypothyroidism showed higher EAE scores after disease induction during adulthood compared to mice gestated in euthyroidism. In addition, spinal cord sections of mice gestated under hypothyroidism that suffered EAE in adulthood showed higher demyelination, CD4+ and CD8+ infiltration, and increased oligodendrocyte death. Conclusions: These results show for the first time that a deficiency in maternal thyroid hormones during gestation can influence the outcome of a central nervous system inflammatory disease, such as EAE, in their offspring. These data strongly support evaluating thyroid hormones in pregnant women and treating hypothyroidism during pregnancy to prevent increased susceptibility to inflammatory diseases in the central nervous system of offspring. PMID:23777566

  1. Traditional Chinese medicine Yisui Tongjing relieved neural severity in experimental autoimmune neuritis rat model

    PubMed Central

    Zhang, Erli; Li, Mingquan; Zhao, Jianjun; Dong, Yuxiang; Yang, Xueqin; Huang, Jingbo

    2016-01-01

    Objective To study the effect of Yisui Tongjing (YSTJ) prescription on motor nerve conduction velocity (MNCV) and microstructure of the sciatic nerve in experimental autoimmune neuritis (EAN) rats, the Guillain–Barré syndrome classic animal models. Materials and methods In this study, we established an EAN model in Lewis rats by immunization. We evaluated the potential clinical application of a traditional Chinese medicine YSTJ by intragastric administration and compared its effect with immunoglobulin. The sciatic MNCV was measured by electrophysiology experiment. Hematoxylin–eosin staining and transmission electron microscope analysis were used to determine the pathologically morphological changes before and after YSTJ application. Results We found that application of YSTJ could significantly alleviate the clinical signs in EAN rats. The treatment also increased MNCV in the sciatic nerve compared to that in the untreated nerve. Demyelination in the sciatic nerve in EAN rats was significantly ameliorated, and newly generated myelinated nerve fibers were observed with treatment of high dose of YSTJ. Conclusion This study showed that the traditional Chinese medicine YSTJ was likely to serve as a therapeutic medicine in autoimmune neuropathies, providing an effective and economic means to the treatment of Guillain–Barré syndrome. PMID:27729792

  2. Experimental and Estimated Rate Constants for the Reactions of Hydroxyl Radicals with Several Halocarbons

    NASA Technical Reports Server (NTRS)

    DeMore, W.B.

    1996-01-01

    Relative rate experiments are used to measure rate constants and temperature dependencies of the reactions of OH with CH3F (41), CH2FCl (31), CH2BrCl (30B1), CH2Br2 (3OB2), CHBr3 (2OB3), CF2BrCHFCl (123aBl(alpha)), and CF2ClCHCl2 (122). Rate constants for additional compounds of these types are estimated using an empirical rate constant estimation method which is based on measured rate constants for a wide range of halocarbons. The experimental data are combined with the estimated and previously reported rate constants to illustrate the effects of F, Cl, and Br substitution on OH rate constants for a series of 19 halomethanes and 25 haloethanes. Application of the estimation technique is further illustrated for some higher hydrofluorocarbons (HFCs), including CHF2CF2CF2CF2H (338pcc), CF3CHFCHFCF2CF3 (43-10mee), CF3CH2CH2CF3 (356ffa), CF3CH2CF2CH2CF3 (458mfcf), CF3CH2CHF2 (245fa), and CF3CH2CF2CH3 (365mfc). The predictions are compared with literature data for these compounds.

  3. Experimental determination of elemental compositions and densities of several common liquid scintillators.

    PubMed

    Rodríguez-Barquero, Leonor; Los Arcos, José M

    2010-01-01

    New accurate data for the density and the elemental composition of several common liquid scintillators have been determined in this work. These data can be used to correctly determine or calculate the counting efficiency of radio-nuclides as well as to evaluate more accurately the uncertainties in LSC measurements due to variability on the composition of scintillators. The discrepancy between nominal densities at 20 degrees C and the real densities at 20 degrees C or 16 degrees C can reach up to 4% among different batches of commercial scintillators all having the same nominal composition. Also significant differences in the elemental composition of commercial cocktails have been found compared to the nominal values. These differences range from 2% up to 260% depending on the element and the scintillator being measured. PMID:20106669

  4. Plasma and skeletal muscle amino acids following severe burn injury in patients and experimental animals.

    PubMed Central

    Stinnett, J D; Alexander, J W; Watanabe, C; MacMillan, B G; Fischer, J E; Morris, M J; Trocki, O; Miskell, P; Edwards, L; James, H

    1982-01-01

    This study describes and analyzes sequential changes in plasma and skeletal muscle free amino acids following severe burn injury. Plasma free amino acids were determined in children (n = 9) with burns averaging 60% total body surface area and were compared with laboratory beagles (n = 44) which received a flame burn totaling 30% of their body surface area. In addition, needle biopsy specimens were obtained from the semitendonosus muscle in the animals to determine free intracellular amino acids. In both patients and animals the amount of total free amino acids in plasma fell following burn, suggesting relative protein deficiency. This drop was primarily due to a 47% drop in nonessential amino acids. However, plasma phenylalanine was consistently higher than normal following burn, and was strongly associated with death and weight loss in both animals and patients, especially when analyzed as a ratio with tyrosine. This finding suggested excessive catabolism, hepatic dysfunction, or both. Plasma levels of several amino acids correlated significantly with weight loss. Alterations in muscle free amino acids generally were similar to plasma amino acids. Exceptions were muscle alanine and glycine which strongly correlated with weight loss. However, the determination of muscle free amino acid profiles did not yield clinically useful information not available from plasma profiles. Plasma levels of liver enzymes suggested progressive hepatic dysfunction. These studies show that the laboratory beagle is a good model for studying the metabolic alterations of amino acids that accompany burn injury, since they mimic humans in many parameters which appear to be most useful with respect to clinical evaluation. PMID:7055386

  5. Pain hypervigilance is associated with greater clinical pain severity and enhanced experimental pain sensitivity among adults with symptomatic knee osteoarthritis

    PubMed Central

    Herbert, Matthew S.; Goodin, Burel R.; Pero, Samuel T.; Schmidt, Jessica K.; Sotolongo, Adriana; Bulls, Hailey W.; Glover, Toni L.; King, Christopher D.; Sibille, Kimberly T.; Cruz-Almeida, Yenisel; Staud, Roland; Fessler, Barri J.; Bradley, Laurence A.; Fillingim, Roger B.

    2014-01-01

    Background Pain hypervigilance is an important aspect of the fear-avoidance model of pain that may help explain individual differences in pain sensitivity among persons with knee osteoarthritis (OA). Purpose The purpose of this study was to examine the contribution of pain hypervigilance to clinical pain severity and experimental pain sensitivity in persons with symptomatic knee OA. Methods We analyzed cross-sectional data from 168 adults with symptomatic knee OA. Quantitative sensory testing was used to measure sensitivity to heat pain, pressure pain, and cold pain, as well as temporal summation of heat pain, a marker of central sensitization. Results Pain hypervigilance was associated with greater clinical pain severity, as well as greater pressure pain. Pain hypervigilance was also a significant predictor of temporal summation of heat pain. Conclusions Pain hypervigilance may be an important contributor to pain reports and experimental pain sensitivity among persons with knee OA. PMID:24352850

  6. Preventing stroke

    MedlinePlus

    ... may ask you to keep track of your blood pressure at home . You should lower it and control it with a healthy diet, exercise, and by taking medicines your health care provider ... the chance of blood clots, which can lead to stroke. Clots are ...

  7. Biotherapies in stroke.

    PubMed

    Detante, O; Jaillard, A; Moisan, A; Barbieux, M; Favre, I M; Garambois, K; Hommel, M; Remy, C

    2014-12-01

    Stroke is the second leading cause of death worldwide and the most common cause of severe disability. Neuroprotection and repair mechanisms supporting endogenous brain plasticity are often insufficient to allow complete recovery. While numerous neuroprotective drugs trials have failed to demonstrate benefits for patients, they have provided interesting translational research lessons related to neurorestorative therapy mechanisms in stroke. Stroke damage is not limited to neurons but involve all brain cell type including the extracellular matrix in a "glio-neurovascular niche". Targeting a range of host brain cells, biotherapies such as growth factors and therapeutic cells, currently hold great promise as a regenerative medical strategy for stroke. These techniques can promote both neuroprotection and delayed neural repair through neuro-synaptogenesis, angiogenesis, oligodendrogliogenesis, axonal sprouting and immunomodulatory effects. Their complex mechanisms of action are interdependent and vary according to the particular growth factor or grafted cell type. For example, while "peripheral" stem or stromal cells can provide paracrine trophic support, neural stem/progenitor cells (NSC) or mature neurons can act as more direct neural replacements. With a wide therapeutic time window after stroke, biotherapies could be used to treat many patients. However, guidelines for selecting the optimal time window, and the best delivery routes and doses are still debated and the answers may depend on the chosen product and its expected mechanism including early neuroprotection, delayed neural repair, trophic systemic transient effects or graft survival and integration. Currently, the great variety of growth factors, cell sources and cell therapy products form a therapeutic arsenal that is available for stroke treatment. Their effective clinical use will require prior careful considerations regarding safety (e.g. tumorgenicity, immunogenicity), potential efficacy, cell

  8. Relationship between elevated soluble CD74 and severity of experimental and clinical ALI/ARDS

    PubMed Central

    Wu, Guosheng; Sun, Yu; Wang, Kang’an; Chen, Zhengli; Wang, Xingtong; Chang, Fei; Li, Ting; Feng, Ping; Xia, Zhaofan

    2016-01-01

    CD74 is expressed on the cell surface of pulmonary macrophages and contributes to macrophage migration inhibitory factor (MIF)-induced inflammatory response in acute lung injury (ALI). A circulating form of CD74 (soluble CD74, sCD74) was recently discovered in autoimmune liver disease. Using two murine ALI models and cells culture, we examined the presence of sCD74 in circulation and alveolar space and preliminarily assessed the biological function of sCD74. The concentrations of sCD74 were increased in serum and bronchoalveolar lavage fluids (BALF) of murine ALI models. The elevated levels of sCD74 in BALF positively correlated with lung permeability and inflammation. In addition, sCD74 is secreted by macrophages in response to MIF stimulation and itself can stimulate the production of inflammatory cytokines. Our clinical study confirmed some findings of basic research. Moreover, we also found Day 3 serum sCD74 levels were associated with worse clinical outcomes. In conclusion, higher serum sCD74 levels may reflect more severe lung injury and may be used to help physicians determine prognosis of acute respiratory distress syndrome (ARDS). PMID:27444250

  9. 4-Phenylbutyric Acid Attenuates Pancreatic Beta-Cell Injury in Rats with Experimental Severe Acute Pancreatitis

    PubMed Central

    Guo, Wen-yi; Zhao, Liang; Xiang, Ming-wei; Mei, Fang-chao; Abliz, Ablikim; Hu, Peng; Deng, Wen-hong; Yu, Jia

    2016-01-01

    Endoplasmic reticulum (ER) stress is a particular process with an imbalance of homeostasis, which plays an important role in pancreatitis, but little is known about how ER stress is implicated in severe acute pancreatitis (SAP) induced pancreatic beta-cell injury. To investigate the effect of 4-phenylbutyric acid (4-PBA) on the beta-cell injury following SAP and the underlying mechanism, twenty-four Sprague-Dawley rats were randomly divided into sham-operation (SO) group, SAP model group, and 4-PBA treatment group. SAP model was induced by infusion of 5% sodium taurocholate into the biliopancreatic duct. 4-PBA or normal saline was injected intraperitoneally for 3 days in respective group before successful modeling. Results showed that 4-PBA attenuated the following: (1) pancreas and islet pathological injuries, (2) serum TNF-α and IL-1β, (3) serum insulin and glucose, (4) beta-cell ultrastructural changes, (5) ER stress markers (BiP, ORP150, and CHOP), Caspase-3, and insulin expression in islet. These results suggested that 4-PBA mitigates pancreatic beta-cell injury and endocrine disorder in SAP, presumably because of its role in inhibiting excessive endoplasmic reticulum stress. This may serve as a new therapeutic target for reducing pancreatic beta-cell injury and endocrine disorder in SAP upon 4-PBA treatment.

  10. Infusion of Bone Marrow Mesenchymal Stem Cells Attenuates Experimental Severe Acute Pancreatitis in Rats

    PubMed Central

    Huang, Dandan; Gao, Jun; Gong, Yanfang; Wu, Hongyu; Xu, Aifang

    2016-01-01

    Background & Aims. Severe acute pancreatitis (SAP) remains a high-mortality disease. Bone marrow (BM) mesenchymal stem cells (MSCs) have been demonstrated to have plasticity of transdifferentiation and to have immunomodulatory functions. In the present study, we assessed the roles of MSCs in SAP and the therapeutic effects of MSC on SAP after transplantation. Methods. A pancreatitis rat model was induced by the injection of taurocholic acid (TCA) into the pancreatic duct. After isolation and characterization of MSC from BM, MSC transplantation was conducted 24 hrs after SAP induction by tail vein injection. The survival rate was observed and MSCs were traced after transplantation. The expression of TNF-α and IL-1β mRNA in the transplantation group was also analyzed. Results. The survival rate of the transplantation group was significantly higher compared to the control group (p < 0.05). Infused MSCs were detected in the pancreas and BM 3 days after transplantation. The expression of TNF-α and IL-1β mRNA in the transplantation group was significantly lower than in the control group in both the pancreas and the lungs (p < 0.05). Conclusions. MSC transplantation could improve the prognosis of SAP rats. Engrafted MSCs have the capacity of homing, migration, and planting during the treatment of SAP. PMID:27721836

  11. 4-Phenylbutyric Acid Attenuates Pancreatic Beta-Cell Injury in Rats with Experimental Severe Acute Pancreatitis

    PubMed Central

    Guo, Wen-yi; Zhao, Liang; Xiang, Ming-wei; Mei, Fang-chao; Abliz, Ablikim; Hu, Peng; Deng, Wen-hong; Yu, Jia

    2016-01-01

    Endoplasmic reticulum (ER) stress is a particular process with an imbalance of homeostasis, which plays an important role in pancreatitis, but little is known about how ER stress is implicated in severe acute pancreatitis (SAP) induced pancreatic beta-cell injury. To investigate the effect of 4-phenylbutyric acid (4-PBA) on the beta-cell injury following SAP and the underlying mechanism, twenty-four Sprague-Dawley rats were randomly divided into sham-operation (SO) group, SAP model group, and 4-PBA treatment group. SAP model was induced by infusion of 5% sodium taurocholate into the biliopancreatic duct. 4-PBA or normal saline was injected intraperitoneally for 3 days in respective group before successful modeling. Results showed that 4-PBA attenuated the following: (1) pancreas and islet pathological injuries, (2) serum TNF-α and IL-1β, (3) serum insulin and glucose, (4) beta-cell ultrastructural changes, (5) ER stress markers (BiP, ORP150, and CHOP), Caspase-3, and insulin expression in islet. These results suggested that 4-PBA mitigates pancreatic beta-cell injury and endocrine disorder in SAP, presumably because of its role in inhibiting excessive endoplasmic reticulum stress. This may serve as a new therapeutic target for reducing pancreatic beta-cell injury and endocrine disorder in SAP upon 4-PBA treatment. PMID:27656209

  12. 4-Phenylbutyric Acid Attenuates Pancreatic Beta-Cell Injury in Rats with Experimental Severe Acute Pancreatitis.

    PubMed

    Hong, Yu-Pu; Guo, Wen-Yi; Wang, Wei-Xing; Zhao, Liang; Xiang, Ming-Wei; Mei, Fang-Chao; Abliz, Ablikim; Hu, Peng; Deng, Wen-Hong; Yu, Jia

    2016-01-01

    Endoplasmic reticulum (ER) stress is a particular process with an imbalance of homeostasis, which plays an important role in pancreatitis, but little is known about how ER stress is implicated in severe acute pancreatitis (SAP) induced pancreatic beta-cell injury. To investigate the effect of 4-phenylbutyric acid (4-PBA) on the beta-cell injury following SAP and the underlying mechanism, twenty-four Sprague-Dawley rats were randomly divided into sham-operation (SO) group, SAP model group, and 4-PBA treatment group. SAP model was induced by infusion of 5% sodium taurocholate into the biliopancreatic duct. 4-PBA or normal saline was injected intraperitoneally for 3 days in respective group before successful modeling. Results showed that 4-PBA attenuated the following: (1) pancreas and islet pathological injuries, (2) serum TNF-α and IL-1β, (3) serum insulin and glucose, (4) beta-cell ultrastructural changes, (5) ER stress markers (BiP, ORP150, and CHOP), Caspase-3, and insulin expression in islet. These results suggested that 4-PBA mitigates pancreatic beta-cell injury and endocrine disorder in SAP, presumably because of its role in inhibiting excessive endoplasmic reticulum stress. This may serve as a new therapeutic target for reducing pancreatic beta-cell injury and endocrine disorder in SAP upon 4-PBA treatment. PMID:27656209

  13. Transplantation for stroke.

    PubMed

    Roitberg, Ben

    2004-04-01

    Stroke is the most common cause of disability in the United States, and one of the leading causes of mortality and disability in the world. The hope that damage to the CNS can be reversed or at least ameliorated is the central idea behind the research into neural repair. The ultimate repair for the brain should restore the entire lost structure and it's function. However, partial benefit is possible from addressing some of the needs of the injured brain. These partial solutions are the basis of current research into brain repair after stroke. An opportunity arises for two kinds of intervention: (1) replacement of neurons; (2) support of existing neurons, to prevent excessive degeneration and promote rewiring and plasticity. Transplantation for stroke in the rat model was regularly reported starting in 1992, demonstrating graft survival and even evidence of connection with the host brain. These studies determined several parameters for future work in stroke models, but ultimately had limited efficacy and did not progress to clinical experiments. A variety of cell types have been tried for restoration of brain function after stroke, mostly in rodent models. Human fetal cells had shown some promise in clinical studies for the treatment of Parkinson's disease. The technical and ethical difficulties associated with these cells promoted a search for alternatives. These include porcine fetal cells, human cultured stem cells, immortalized cell lines, marrow stromal cells, Sertoli cells pineal cells, and other sources. Human clonal cell lines have few ethical limitations, but some questions remain regarding their safety and efficacy. Autologous somatic stem cells are a very attractive source--there are no ethical concerns and graft rejection is not an issue. However, it is not clear that somatic cells can are plastic enough and can be safely induced to a neural fate. Restorative treatment for stroke is a new field of study. Naturally, new ideas abound and many strategies

  14. Brainstem structures are primarily affected in an experimental model of severe scorpion envenomation.

    PubMed

    Guidine, Patrícia Alves Maia; Cash, Diana; Drumond, Luciana Estefani; de Souza E Rezende, Gustavo Henrique; Massensini, André Ricardo; Williams, Steve Charles Rees; Moraes-Santos, Tasso; Moraes, Márcio Flávio Dutra; Mesquita, Michel Bernanos Soares

    2014-01-01

    Severe scorpion envenoming (SSE) is more frequent in children and is characterized by systemic dysfunctions with a mortality rate of up to 9%. Recent evidence shows that the central nervous system (CNS) plays a key role in triggering the cascade of symptoms present in SSE. The age-dependent role of the CNS in SSE lethality may be summarized in 3 hypotheses: (1) the shown increased blood brain barrier permeability of infants to the toxins would especially and primarily compromise neurovegetative control areas, (2) the neurons within these areas have high affinity to the toxins, and (3) the neurovascular interaction is such that SSE metabolically compromises proper function of toxin-targeted areas. A pharmacological magnetic resonance imaging paradigm was used to evaluate localized hemodynamic changes in relative cerebral blood volume (rCBV) for 30 min after the injection of TsTX, the most lethal toxin from the venom of the Tityus serrulatus scorpion. The brainstem showed significant rCBV reduction 1 min after TsTX administration, whereas rostral brain areas had delayed increase in rCBV (confirmed by laser Doppler measurements of cortical cerebral blood flow). Moreover, metabolic activity by 14C-2-deoxyglucose autoradiography showed the highest relative increase at the brainstem. To test whether TsTX has high affinity to brainstem neurons, the lateral ventricle was injected with Alexa Fluor 568 TsTX. Although some neurons showed intense fluorescence, the labeling pattern suggests that specific neurons were targeted. Altogether, these results suggest that brainstem areas involved in neurovegetative control are most likely within the primary structures triggering the cascade of symptoms present in SSE.

  15. Mismatch Negativity (MMN) in Freely-Moving Rats with Several Experimental Controls

    PubMed Central

    Harms, Lauren; Fulham, W. Ross; Todd, Juanita; Budd, Timothy W.; Hunter, Michael; Meehan, Crystal; Penttonen, Markku; Schall, Ulrich; Zavitsanou, Katerina; Hodgson, Deborah M.; Michie, Patricia T.

    2014-01-01

    Mismatch negativity (MMN) is a scalp-recorded electrical potential that occurs in humans in response to an auditory stimulus that defies previously established patterns of regularity. MMN amplitude is reduced in people with schizophrenia. In this study, we aimed to develop a robust and replicable rat model of MMN, as a platform for a more thorough understanding of the neurobiology underlying MMN. One of the major concerns for animal models of MMN is whether the rodent brain is capable of producing a human-like MMN, which is not a consequence of neural adaptation to repetitive stimuli. We therefore tested several methods that have been used to control for adaptation and differential exogenous responses to stimuli within the oddball paradigm. Epidural electroencephalographic electrodes were surgically implanted over different cortical locations in adult rats. Encephalographic data were recorded using wireless telemetry while the freely-moving rats were presented with auditory oddball stimuli to assess mismatch responses. Three control sequences were utilized: the flip-flop control was used to control for differential responses to the physical characteristics of standards and deviants; the many standards control was used to control for differential adaptation, as was the cascade control. Both adaptation and adaptation-independent deviance detection were observed for high frequency (pitch), but not low frequency deviants. In addition, the many standards control method was found to be the optimal method for observing both adaptation effects and adaptation-independent mismatch responses in rats. Inconclusive results arose from the cascade control design as it is not yet clear whether rats can encode the complex pattern present in the control sequence. These data contribute to a growing body of evidence supporting the hypothesis that rat brain is indeed capable of exhibiting human-like MMN, and that the rat model is a viable platform for the further investigation of the

  16. Brainstem structures are primarily affected in an experimental model of severe scorpion envenomation.

    PubMed

    Guidine, Patrícia Alves Maia; Cash, Diana; Drumond, Luciana Estefani; de Souza E Rezende, Gustavo Henrique; Massensini, André Ricardo; Williams, Steve Charles Rees; Moraes-Santos, Tasso; Moraes, Márcio Flávio Dutra; Mesquita, Michel Bernanos Soares

    2014-01-01

    Severe scorpion envenoming (SSE) is more frequent in children and is characterized by systemic dysfunctions with a mortality rate of up to 9%. Recent evidence shows that the central nervous system (CNS) plays a key role in triggering the cascade of symptoms present in SSE. The age-dependent role of the CNS in SSE lethality may be summarized in 3 hypotheses: (1) the shown increased blood brain barrier permeability of infants to the toxins would especially and primarily compromise neurovegetative control areas, (2) the neurons within these areas have high affinity to the toxins, and (3) the neurovascular interaction is such that SSE metabolically compromises proper function of toxin-targeted areas. A pharmacological magnetic resonance imaging paradigm was used to evaluate localized hemodynamic changes in relative cerebral blood volume (rCBV) for 30 min after the injection of TsTX, the most lethal toxin from the venom of the Tityus serrulatus scorpion. The brainstem showed significant rCBV reduction 1 min after TsTX administration, whereas rostral brain areas had delayed increase in rCBV (confirmed by laser Doppler measurements of cortical cerebral blood flow). Moreover, metabolic activity by 14C-2-deoxyglucose autoradiography showed the highest relative increase at the brainstem. To test whether TsTX has high affinity to brainstem neurons, the lateral ventricle was injected with Alexa Fluor 568 TsTX. Although some neurons showed intense fluorescence, the labeling pattern suggests that specific neurons were targeted. Altogether, these results suggest that brainstem areas involved in neurovegetative control are most likely within the primary structures triggering the cascade of symptoms present in SSE. PMID:24105889

  17. Effects of allyl isothiocyanate from horseradish on several experimental gastric lesions in rats.

    PubMed

    Matsuda, Hisashi; Ochi, Momotaro; Nagatomo, Akifumi; Yoshikawa, Masayuki

    2007-04-30

    Allyl isothiocyanate is well known to be a principal pungent constituent of horseradish and an agonist for transient receptor potential (TRP) A1. Ally isothiocyanate markedly inhibited the formation of gastric lesions induced by ethanol (1.5 ml/rat, p.o.), 0.6 M HCl (1.5 ml/rat, p.o.), 1% ammonia (1.5 ml/rat, p.o.), and aspirin (150 mg/kg, p.o.) (ED(50)=1.6, 2.2, 1.7, ca. 6.5 mg/kg, p.o.). It also significantly inhibited the formation of gastric lesions induced by indomethacin (20 mg/kg, p.o.), though the inhibition was ca. 60% at a high dose (40 mg/kg, p.o.). Furthermore, several synthetic isothiocyanate compounds also significantly inhibited ethanol and indomethacin-induced gastric lesions. Whereas, TRPV1 agonists, capsaicin and piperine, inhibited gastric lesions induced by ethanol, 1% ammonia, and aspirin, but had less of an effect on 0.6 M HCl-induced gastric lesions. With regard to mode of action, the protective effects of ally isothiocyanate on ethanol-induced gastric lesions were attenuated by pretreatment with indomethacin, but not with N(G)-nitro-L-arginine methyl ester hydrochloride (L-NAME), or ruthenium red. Pretreatment with indomethacin reduced the protective effects of piperine, and L-NAME reduced the effects of capsaicin and omeprazole. Furthermore, ruthenium red reduced the effects of capsaicin, piperine, and omeprazole. These findings suggest that endogenous prostaglandins play an important role in the protective effect of allyl isothiocyanate in ethanol-induced gastric lesions different from capsaicin, piperine, and omeprazole.

  18. Rehabilitation After Stroke

    PubMed Central

    Kottke, Frederic J.

    1970-01-01

    The more severely involved the stroke patient is or the greater is the pre-existing physical disability, the greater is the need for special rehabilitation services to restore him to his optimal level of performance. The availability of resources in the family and community are important factors in determining whether or not the patient will need to be treated in a rehabilitation center. There is no contraindication to early initiation of rehabilitation and those patients for whom rehabilitation is initiated immediately after the stroke have the most rapid and optimal recovery. Ninety to 95 percent of hemiplegics can learn to walk. Forty percent of hemiplegics get good return of function in their upper extremity. Sixty-five percent of hemiplegics become independent in self-care and ambulation. For the stroke patient who does not have complicating disabilities independence in self-care and ambulation can be accomplished in 4 to 8 weeks. Intellectual or emotional problems indicate the need for a carefully planned rehabilitation program. The families of stroke patients need counseling and training regarding their responsibilities and duties to the patient. Imagesp47-aFigure 2Figure 3Figure 6Figure 8 PMID:20468595

  19. ModA2 Phasevarion Switching in Nontypeable Haemophilus influenzae Increases the Severity of Experimental Otitis Media.

    PubMed

    Brockman, Kenneth L; Jurcisek, Joseph A; Atack, John M; Srikhanta, Yogitha N; Jennings, Michael P; Bakaletz, Lauren O

    2016-09-01

    Several human-adapted bacterial pathogens use a phasevarion (ie, a phase-variable regulon) to rapidly and reversibly regulate the expression of many genes, which include known virulence factors, yet the influence of phasevarion-mediated regulation in pathogenesis remains poorly understood. Here we examine the impact of the nontypeable Haemophilus influenzae (NTHI) ModA2 phasevarion on pathogenesis and disease severity in a chinchilla model of experimental otitis media. Chinchillas were challenged with NTHI variant populations that were either inoculated ON and remained ON, inoculated OFF and shifted ON, or inoculated OFF and remained OFF, within the middle ear. We show that populations that shift from OFF to ON within the middle ear induce significantly greater disease severity than populations that are unable to shift. These observations support the importance of phasevarion switching in NTHI pathogenesis and the necessity to considered phasevarion regulation when developing methods to treat and prevent infection.

  20. ModA2 Phasevarion Switching in Nontypeable Haemophilus influenzae Increases the Severity of Experimental Otitis Media.

    PubMed

    Brockman, Kenneth L; Jurcisek, Joseph A; Atack, John M; Srikhanta, Yogitha N; Jennings, Michael P; Bakaletz, Lauren O

    2016-09-01

    Several human-adapted bacterial pathogens use a phasevarion (ie, a phase-variable regulon) to rapidly and reversibly regulate the expression of many genes, which include known virulence factors, yet the influence of phasevarion-mediated regulation in pathogenesis remains poorly understood. Here we examine the impact of the nontypeable Haemophilus influenzae (NTHI) ModA2 phasevarion on pathogenesis and disease severity in a chinchilla model of experimental otitis media. Chinchillas were challenged with NTHI variant populations that were either inoculated ON and remained ON, inoculated OFF and shifted ON, or inoculated OFF and remained OFF, within the middle ear. We show that populations that shift from OFF to ON within the middle ear induce significantly greater disease severity than populations that are unable to shift. These observations support the importance of phasevarion switching in NTHI pathogenesis and the necessity to considered phasevarion regulation when developing methods to treat and prevent infection. PMID:27288538

  1. Early seizures in acute stroke

    PubMed Central

    Mohamed, Chraa; Kissani, Najib

    2015-01-01

    Early seizures (ES) may complicate the clinical course of patients with acute stroke. The aim of this study was to assess the frequency and the predictive factors for early seizures as well the clinical outcome in patients with first-ever stroke. A total of 352 consecutive patients with first-ever stroke, admitted to our department, were included in this retrospective study. Early seizures were defined as seizures occurring within 7 days from acute stroke. Patients with history of epilepsy were excluded. About 47 patients (13%) had early seizure, and 8 had a status epilepticus. We had 28 women and 19 men. The mean age was 71.6 ± 14.6. They were significantly more common in patients with cortical involvement, severe and large stroke, and in patient with cortical associated hemorrhage. ES were associated with an increase in adverse outcome (mortality and disability). Early seizures occured in about 13% of patients with acute stroke. In these patients hemorrhagic transformation is a predictive factor for ES. ES seem to be associated with a worse outcome after acute stroke. PMID:26097640

  2. Estimation of hydrogen sulfide emission rates at several wastewater treatment plants through experimental concentration measurements and dispersion modeling.

    PubMed

    Llavador Colomer, Fernando; Espinós Morató, Héctor; Mantilla Iglesias, Enrique

    2012-07-01

    The management and operation of wastewater treatment plants (WWTP) usually involve the release into the atmosphere of malodorous substances with the potential to reduce the quality of life of people living nearby. In this type of facility, anaerobic degradation processes contribute to the generation of hydrogen sulfide (H2S), often at quite high concentrations; thus, the presence of this chemical compound in the atmosphere can be a good indicator of the occurrence and intensity of the olfactory impact in a specific area. The present paper describes the experimental and modelling work being carried out by CEAM-UMH in the surroundings of several wastewater treatment plants located in the Valencia Autonomous Community (Spain). This work has permitted the estimation of H2S emission rates at different WWTPs under different environmental and operating conditions. Our methodological approach for analyzing and describing the most relevant aspects of the olfactory impact consisted of several experimental campaigns involving intensive field measurements using passive samplers in the vicinity of several WWTPs, in combination with numerical simulation results from a diagnostic dispersion model. A meteorological tower at each WWTP provided the input values for the dispersion code, ensuring a good fit of the advective component and therefore more confidence in the modelled concentration field in response to environmental conditions. Then, comparisons between simulated and experimental H2S concentrations yielded estimates of the global emission rate for this substance at several WWTPs at different time periods. The results obtained show a certain degree of temporal and spatial (between-plant) variability (possibly due to both operational and environmental conditions). Nevertheless, and more importantly, the results show a high degree of uniformity in the estimates, which consistently stay within the same order of magnitude.

  3. Estimation of hydrogen sulfide emission rates at several wastewater treatment plants through experimental concentration measurements and dispersion modeling.

    PubMed

    Llavador Colomer, Fernando; Espinós Morató, Héctor; Mantilla Iglesias, Enrique

    2012-07-01

    The management and operation of wastewater treatment plants (WWTP) usually involve the release into the atmosphere of malodorous substances with the potential to reduce the quality of life of people living nearby. In this type of facility, anaerobic degradation processes contribute to the generation of hydrogen sulfide (H2S), often at quite high concentrations; thus, the presence of this chemical compound in the atmosphere can be a good indicator of the occurrence and intensity of the olfactory impact in a specific area. The present paper describes the experimental and modelling work being carried out by CEAM-UMH in the surroundings of several wastewater treatment plants located in the Valencia Autonomous Community (Spain). This work has permitted the estimation of H2S emission rates at different WWTPs under different environmental and operating conditions. Our methodological approach for analyzing and describing the most relevant aspects of the olfactory impact consisted of several experimental campaigns involving intensive field measurements using passive samplers in the vicinity of several WWTPs, in combination with numerical simulation results from a diagnostic dispersion model. A meteorological tower at each WWTP provided the input values for the dispersion code, ensuring a good fit of the advective component and therefore more confidence in the modelled concentration field in response to environmental conditions. Then, comparisons between simulated and experimental H2S concentrations yielded estimates of the global emission rate for this substance at several WWTPs at different time periods. The results obtained show a certain degree of temporal and spatial (between-plant) variability (possibly due to both operational and environmental conditions). Nevertheless, and more importantly, the results show a high degree of uniformity in the estimates, which consistently stay within the same order of magnitude. PMID:22866577

  4. Arterial ischemic stroke in HIV

    PubMed Central

    Bryer, Alan; Lucas, Sebastian; Stanley, Alan; Allain, Theresa J.; Joekes, Elizabeth; Emsley, Hedley; Turnbull, Ian; Downey, Colin; Toh, Cheng-Hock; Brown, Kevin; Brown, David; Ison, Catherine; Smith, Colin; Corbett, Elizabeth L.; Nath, Avindra; Heyderman, Robert S.; Connor, Myles D.; Solomon, Tom

    2016-01-01

    HIV infection, and potentially its treatment, increases the risk of an arterial ischemic stroke. Multiple etiologies and lack of clear case definitions inhibit progress in this field. Several etiologies, many treatable, are relevant to HIV-related stroke. To fully understand the mechanisms and the terminology used, a robust classification algorithm to help ascribe the various etiologies is needed. This consensus paper considers the strengths and limitations of current case definitions in the context of HIV infection. The case definitions for the major etiologies in HIV-related strokes were refined (e.g., varicella zoster vasculopathy and antiphospholipid syndrome) and in some instances new case definitions were described (e.g., HIV-associated vasculopathy). These case definitions provided a framework for an algorithm to help assign a final diagnosis, and help classify the subtypes of HIV etiology in ischemic stroke. PMID:27386505

  5. Atherosclerosis and Stroke

    MedlinePlus

    ... Stroke When the Beat is Off - Atrial Fibrillation Atherosclerosis and Stroke How Cardiovascular & Stroke Risks Relate Problems ... of LDL cholesterol contribute to the development of atherosclerosis as the cholesterol is deposited in artery walls, ...

  6. The "Know Stroke" Campaign

    MedlinePlus

    ... Current Issue Past Issues Special Section The "Know Stroke" Campaign Past Issues / Summer 2007 Table of Contents ... campaign for the U.S. Hispanic community. 1 Know Stroke A stroke occurs when the blood supply to ...

  7. National Stroke Association

    MedlinePlus

    ... Spread the Word Advocate Share Spread the Word Contact Us Contact Us 1-800-STROKES (787-6537) 9707 E. ... Stroke En Espanol Stroke Facts Come Back Strong Contact Us 1-800-787-6537 9707 E. Easter ...

  8. Experimental testing of total knee replacements with UHMW-PE inserts: impact of severe wear test conditions.

    PubMed

    Zietz, Carmen; Reinders, Joern; Schwiesau, Jens; Paulus, Alexander; Kretzer, Jan Philippe; Grupp, Thomas; Utzschneider, Sandra; Bader, Rainer

    2015-03-01

    Aseptic implant loosening due to inflammatory reactions to wear debris is the main reason for the revision of total knee replacements (TKR). Hence, the decrease in polyethylene wear particle generation from the articulating surfaces is aimed at improving implant design and material. For preclinical testing of new TKR systems standardized wear tests are required. However, these wear tests do not reproduce the entire in vivo situation, since the pattern and amount of wear and subsequent implant failure are underestimated. Therefore, daily activity, kinematics, implant aging and position, third-body-wear and surface properties have to be considered to estimate the wear of implant components in vivo. Hence, severe test conditions are in demand for a better reproduction of the in vivo situation of TKR. In the present article an overview of different experimental wear test scenarios considering clinically relevant polyethylene wear situations using severe test conditions is presented. PMID:25716024

  9. Early results from an experimental program to determine the behavior of containment piping penetration bellows subjected to severe accident conditions

    SciTech Connect

    Lambert, L.D.; Parks, M.B.

    1994-09-01

    Containment piping penetration bellows are an integral part of the pressure boundary in steel containments in the United States (US). Their purpose is to minimize loading on the containment shell caused by differential movement between the piping and the containment. This differential movement is typically caused by thermal gradients generated during startup and shutdown of the reactor, but can be caused by earthquake, a loss-of-coolant accident (LOCA), or ``severe`` accidents. In the event of a severe accident, the bellows would be subjected to pressure, temperature, and deflection well beyond the design basis. Most bellows are installed such that they would be subjected to elevated internal pressure, elevated temperature, axial compression, and lateral deflection during a severe accident. A few bellows would be subjected to external pressure and axial elongation, as well as elevated temperature and lateral deflection. The purpose of this experimental program is to examine the potential for leakage of containment bellows during a severe accident. The test series subjects bellows to various levels and combinations of internal pressure, elevated temperature, axial compression or elongation, and lateral deformation. The experiments are being conducted in two parts. For Part 1, all bellows specimens are tested in ``like-new`` condition, without regard for the possible degrading effect of corrosion that has been observed in some containment piping bellows in the US Part I testing, which included 13 bellows tests, has been completed. The second part of the experimental program, in which bellows are subjected to simulated corrosive environments prior to testing, has just just begun. The Part I experiments have shown that bellows in ``like-new`` condition can withstand elevated temperatures and pressures along with large deformations before leaking. In most cases, the like-new bellows were fully compressed without developing any leakage.

  10. Experimental Droplet Impingement on Several Two-Dimensional Airfoils with Thickness Ratios of 6 to 16 Percent

    NASA Technical Reports Server (NTRS)

    Gelder, Thomas F.; Smyers, William H., Jr.; VonGlahn, Uwe

    1956-01-01

    The rate and area of cloud droplet impingement on several two-dimensional swept and unswept airfoils were obtained experimentally in the NACA Lewis icing tunnel with a dye-tracer technique. Airfoil thickness ratios of 6 to 16 percent; angles of attack from 0 deg to 12 deg, and chord sizes from 13 to 96 inches were included in the study. The data were obtained at 152 knots and are extended to other conditions by dimensionless impingement parameters. In general, the data show that the total and local collection efficiencies and impingement limits are primary functions of the modified inertia parameter (in which airspeed, droplet size, and body size are the most significant variables) and the airfoil thickness ratio. Local collection efficiencies and impingement limits also depend on angle of attack. Secondary factors affecting impingement characteristics are airfoil shape, camber, and sweep angle. The impingement characteristics obtained experimentally for the airfoils were within +/-10 percent on the average of the characteristics calculated from theoretical trajectories. Over the range of conditions studied, the experimental data demonstrate that a specific method can be used to predict the impingement characteristics of swept airfoils with large aspect ratios from the data for unswept airfoils of the same series.

  11. Stroke Knowledge in Spanish-speaking populations

    PubMed Central

    Hawkes, Maximiliano A; Ameriso, Sebastián F; Willey, Joshua Z

    2015-01-01

    Background Spanish is the second most spoken language in the world. Spanish-speaking populations (SSP) have heterogeneous cultural backgrounds, racial and ethnical origins, economic status, and access to health care systems. There are no published reviews about stroke knowledge in SSP. We reviewed the existing literature addressing stroke knowledge among SSP and propose future directions for research. Summary We identified 18 suitable studies by searching PubMed, Lilacs, Scopus, Embase, Cochrane and Scielo databases, and looking at reference lists of eligible articles. We also included 2 conference abstracts. Data related to stroke knowledge from studies of Spanish-speakers was analyzed. Key messages Little is known about stroke knowledge in SSP, especially in Latin America. Information is poor even among subjects at risk, stroke patients, stroke survivors, and health care providers. “Ictus”, the word used for stroke in Spanish, is largely unrecognized among subjects at risk. Furthermore, access to medical care and presence of neurologists are suboptimal in many regions. There are several potential issues to solve regarding stroke knowledge and stroke care in SSP. Programs to educate the general population and non-neurologists medical providers in stroke and telemedicine may be suitable options to improve the present situation. PMID:25871697

  12. The Epidemiology of Atrial Fibrillation and Stroke.

    PubMed

    Pistoia, Francesca; Sacco, Simona; Tiseo, Cindy; Degan, Diana; Ornello, Raffaele; Carolei, Antonio

    2016-05-01

    The burden of stroke is increasing due to aging population and unhealthy lifestyle habits. The considerable rise in atrial fibrillation (AF) is due to greater diffusion of risk factors and screening programs. The link between AF and ischemic stroke is strong. The subtype most commonly associated with AF is cardioembolic stroke, which is particularly severe and shows the highest rates of mortality and permanent disability. A trend toward a higher prevalence of cardioembolic stroke in high-income countries is probably due to the greater diffusion of AF and the control of atherosclerotic of risk factors. PMID:27150174

  13. Role of echocardiography in patients with stroke.

    PubMed

    Nakanishi, Koki; Homma, Shunichi

    2016-08-01

    Investigation of potential embolic source is an important diagnostic step in treating patients with ischemic stroke and transient ischemic attack. Cardiogenic embolism has been estimated to be the causative factor in 15-30% of all cases of ischemic stroke. Cardioembolic strokes are generally severe and recurrence and mortality rate high. Various cardiac disorders including atrial fibrillation, ventricular thrombus, valvular heart disease, cardiac tumors, and structural heart defects can cause cardioembolic stroke. Although the aortic arch is not a cardiac structure, it is usually considered under source of cardiac embolism (cardioaortic source) and is reviewed in this article. Echocardiography (both transthoracic and transesophageal) is a widely used and versatile technique that can provide comprehensive information of thromboembolic risk in patients with stroke. This article reviews potential cardiac sources of stroke and discusses the role of echocardiography in clinical practice. PMID:27256218

  14. Canadian stroke best practice recommendations: Stroke rehabilitation practice guidelines, update 2015.

    PubMed

    Hebert, Debbie; Lindsay, M Patrice; McIntyre, Amanda; Kirton, Adam; Rumney, Peter G; Bagg, Stephen; Bayley, Mark; Dowlatshahi, Dar; Dukelow, Sean; Garnhum, Maridee; Glasser, Ev; Halabi, Mary-Lou; Kang, Ester; MacKay-Lyons, Marilyn; Martino, Rosemary; Rochette, Annie; Rowe, Sarah; Salbach, Nancy; Semenko, Brenda; Stack, Bridget; Swinton, Luchie; Weber, Valentine; Mayer, Matthew; Verrilli, Sue; DeVeber, Gabrielle; Andersen, John; Barlow, Karen; Cassidy, Caitlin; Dilenge, Marie-Emmanuelle; Fehlings, Darcy; Hung, Ryan; Iruthayarajah, Jerome; Lenz, Laura; Majnemer, Annette; Purtzki, Jacqueline; Rafay, Mubeen; Sonnenberg, Lyn K; Townley, Ashleigh; Janzen, Shannon; Foley, Norine; Teasell, Robert

    2016-06-01

    Stroke rehabilitation is a progressive, dynamic, goal-orientated process aimed at enabling a person with impairment to reach their optimal physical, cognitive, emotional, communicative, social and/or functional activity level. After a stroke, patients often continue to require rehabilitation for persistent deficits related to spasticity, upper and lower extremity dysfunction, shoulder and central pain, mobility/gait, dysphagia, vision, and communication. Each year in Canada 62,000 people experience a stroke. Among stroke survivors, over 6500 individuals access in-patient stroke rehabilitation and stay a median of 30 days (inter-quartile range 19 to 45 days). The 2015 update of the Canadian Stroke Best Practice Recommendations: Stroke Rehabilitation Practice Guidelines is a comprehensive summary of current evidence-based recommendations for all members of multidisciplinary teams working in a range of settings, who provide care to patients following stroke. These recommendations have been developed to address both the organization of stroke rehabilitation within a system of care (i.e., Initial Rehabilitation Assessment; Stroke Rehabilitation Units; Stroke Rehabilitation Teams; Delivery; Outpatient and Community-Based Rehabilitation), and specific interventions and management in stroke recovery and direct clinical care (i.e., Upper Extremity Dysfunction; Lower Extremity Dysfunction; Dysphagia and Malnutrition; Visual-Perceptual Deficits; Central Pain; Communication; Life Roles). In addition, stroke happens at any age, and therefore a new section has been added to the 2015 update to highlight components of stroke rehabilitation for children who have experienced a stroke, either prenatally, as a newborn, or during childhood. All recommendations have been assigned a level of evidence which reflects the strength and quality of current research evidence available to support the recommendation. The updated Rehabilitation Clinical Practice Guidelines feature several

  15. Canadian stroke best practice recommendations: Stroke rehabilitation practice guidelines, update 2015.

    PubMed

    Hebert, Debbie; Lindsay, M Patrice; McIntyre, Amanda; Kirton, Adam; Rumney, Peter G; Bagg, Stephen; Bayley, Mark; Dowlatshahi, Dar; Dukelow, Sean; Garnhum, Maridee; Glasser, Ev; Halabi, Mary-Lou; Kang, Ester; MacKay-Lyons, Marilyn; Martino, Rosemary; Rochette, Annie; Rowe, Sarah; Salbach, Nancy; Semenko, Brenda; Stack, Bridget; Swinton, Luchie; Weber, Valentine; Mayer, Matthew; Verrilli, Sue; DeVeber, Gabrielle; Andersen, John; Barlow, Karen; Cassidy, Caitlin; Dilenge, Marie-Emmanuelle; Fehlings, Darcy; Hung, Ryan; Iruthayarajah, Jerome; Lenz, Laura; Majnemer, Annette; Purtzki, Jacqueline; Rafay, Mubeen; Sonnenberg, Lyn K; Townley, Ashleigh; Janzen, Shannon; Foley, Norine; Teasell, Robert

    2016-06-01

    Stroke rehabilitation is a progressive, dynamic, goal-orientated process aimed at enabling a person with impairment to reach their optimal physical, cognitive, emotional, communicative, social and/or functional activity level. After a stroke, patients often continue to require rehabilitation for persistent deficits related to spasticity, upper and lower extremity dysfunction, shoulder and central pain, mobility/gait, dysphagia, vision, and communication. Each year in Canada 62,000 people experience a stroke. Among stroke survivors, over 6500 individuals access in-patient stroke rehabilitation and stay a median of 30 days (inter-quartile range 19 to 45 days). The 2015 update of the Canadian Stroke Best Practice Recommendations: Stroke Rehabilitation Practice Guidelines is a comprehensive summary of current evidence-based recommendations for all members of multidisciplinary teams working in a range of settings, who provide care to patients following stroke. These recommendations have been developed to address both the organization of stroke rehabilitation within a system of care (i.e., Initial Rehabilitation Assessment; Stroke Rehabilitation Units; Stroke Rehabilitation Teams; Delivery; Outpatient and Community-Based Rehabilitation), and specific interventions and management in stroke recovery and direct clinical care (i.e., Upper Extremity Dysfunction; Lower Extremity Dysfunction; Dysphagia and Malnutrition; Visual-Perceptual Deficits; Central Pain; Communication; Life Roles). In addition, stroke happens at any age, and therefore a new section has been added to the 2015 update to highlight components of stroke rehabilitation for children who have experienced a stroke, either prenatally, as a newborn, or during childhood. All recommendations have been assigned a level of evidence which reflects the strength and quality of current research evidence available to support the recommendation. The updated Rehabilitation Clinical Practice Guidelines feature several

  16. Correlation between diarrhea severity and oocyst count via quantitative PCR or fluorescence microscopy in experimental cryptosporidiosis in calves.

    PubMed

    Operario, Darwin J; Bristol, Lauren S; Liotta, Janice; Nydam, Daryl V; Houpt, Eric R

    2015-01-01

    Cryptosporidium is an important diarrhea-associated pathogen, however the correlation between parasite burden and diarrhea severity remains unclear. We studied this relationship in 10 experimentally infected calves using immunofluorescence microscopy and real-time polymerase chain reaction (qPCR) (N = 124 fecal samples). The qPCR data were corrected for extraction/amplification efficiency and gene copy number to generate parasite counts. The qPCR and microscopic oocyst quantities exhibited significant correlation (R(2) = 0.33, P < 0.05), however qPCR had increased sensitivity. Upon comparison with diarrhea severity scores (from 0 to 3), a PCR-based count of ≥ 2.6 × 10(5) parasites or an immunofluorescence microscopy count of ≥ 4.5 × 10(4) oocysts were discriminatory predictors of moderate-to-severe diarrhea (versus no-to-mild diarrhea), with accuracies and predictive values of 72-82%. In summary, a quantitative approach for Cryptosporidium can refine predictive power for diarrhea and appears useful for distinguishing clinical cryptosporidiosis versus subclinical infection.

  17. Serum erythropoietin and outcome after ischaemic stroke: a prospective study

    PubMed Central

    Åberg, N David; Stanne, Tara M; Jood, Katarina; Schiöler, Linus; Blomstrand, Christian; Andreasson, Ulf; Blennow, Kaj; Zetterberg, Henrik; Isgaard, Jörgen; Jern, Christina; Svensson, Johan

    2016-01-01

    Objectives Erythropoietin (EPO), which is inversely associated with blood haemoglobin (Hb), exerts neuroprotective effects in experimental ischaemic stroke (IS). However, clinical treatment trials have so far been negative. Here, in patients with IS, we analysed whether serum EPO is associated with (1) initial stroke severity, (2) recovery and (3) functional outcome. Design Prospective. Controls available at baseline. Setting A Swedish hospital-initiated study with outpatient follow-up after 3 months. Participants Patients (n=600; 64% males, mean age 56 years, controls n=600) were included from the Sahlgrenska Academy Study on IS (SAHLSIS). Primary and secondary outcome measures In addition to EPO and Hb, initial stroke severity was assessed by the Scandinavian Stroke Scale (SSS) and compared with SSS after 3 months (follow-up) as a measure of recovery. Functional outcome was evaluated using the modified Rankin Scale (mRS) at follow-up. Serum EPO and SSS were divided into quintiles in the multivariate regression analyses. Results Serum EPO was 21% and 31% higher than in controls at the acute phase of IS and follow-up, respectively. In patients, acute serum EPO was 19.5% higher in severe versus mild IS. The highest acute EPO quintile adjusted for sex, age and Hb was associated with worse stroke severity quintile (OR 1.70, 95% CI 1.00 to 2.87), better stroke recovery quintile (OR 1.93, CI 1.09 to 3.41) and unfavourable mRS 3–6 (OR 2.59, CI 1.15 to 5.80). However, the fourth quintile of EPO increase (from acute to follow-up) was associated with favourable mRS 0–2 (OR 3.42, CI 1.46 to 8.03). Only the last association withstood full adjustment. Conclusions The crude associations between EPO and worse stroke severity and outcome lost significance after multivariate modelling. However, in patients in whom EPO increased, the association with favourable outcome remained after adjustment for multiple covariates. PMID:26916692

  18. The Christchurch earthquake stroke incidence study.

    PubMed

    Wu, Teddy Y; Cheung, Jeanette; Cole, David; Fink, John N

    2014-03-01

    We examined the impact of major earthquakes on acute stroke admissions by a retrospective review of stroke admissions in the 6 weeks following the 4 September 2010 and 22 February 2011 earthquakes. The control period was the corresponding 6 weeks in the previous year. In the 6 weeks following the September 2010 earthquake there were 97 acute stroke admissions, with 79 (81.4%) ischaemic infarctions. This was similar to the 2009 control period which had 104 acute stroke admissions, of whom 80 (76.9%) had ischaemic infarction. In the 6 weeks following the February 2011 earthquake, there were 71 stroke admissions, and 61 (79.2%) were ischaemic infarction. This was less than the 96 strokes (72 [75%] ischaemic infarction) in the corresponding control period. None of the comparisons were statistically significant. There was also no difference in the rate of cardioembolic infarction from atrial fibrillation between the study periods. Patients admitted during the February 2011 earthquake period were less likely to be discharged directly home when compared to the control period (31.2% versus 46.9%, p=0.036). There was no observable trend in the number of weekly stroke admissions between the 2 weeks leading to and 6 weeks following the earthquakes. Our results suggest that severe psychological stress from earthquakes did not influence the subsequent short term risk of acute stroke, but the severity of the earthquake in February 2011 and associated civil structural damages may have influenced the pattern of discharge for stroke patients.

  19. Using Stroke Removal to Investigate Chinese Character Identification during Reading: Evidence from Eye Movements

    ERIC Educational Resources Information Center

    Yan, Guoli; Bai, Xuejun; Zang, Chuanli; Bian, Qian; Cui, Lei; Qi, Wei; Rayner, Keith; Liversedge, Simon P.

    2012-01-01

    We explored the effect of stroke removal from Chinese characters on eye movements during reading to examine the role of stroke encoding in character identification. Experimental sentences were comprised of characters with different proportions of strokes removed (15, 30, and 50%), and different types of strokes removed (beginning, ending, and…

  20. EphA4 Receptor Tyrosine Kinase Is a Modulator of Onset and Disease Severity of Experimental Autoimmune Encephalomyelitis (EAE)

    PubMed Central

    Gresle, Melissa M.; Jonas, Anna; Kemper, Dennis; Doherty, William; Fabri, Louis J.; Owczarek, Catherine M.; Pearse, Martin; Boyd, Andrew W.; Kilpatrick, Trevor J.; Butzkueven, Helmut; Turnley, Ann M.

    2013-01-01

    The EphA4 receptor tyrosine kinase is a major regulator of axonal growth and astrocyte reactivity and is a possible inflammatory mediator. Given that multiple sclerosis (MS) is primarily an inflammatory demyelinating disease and in mouse models of MS, such as experimental autoimmune encephalomyelitis (EAE), axonal degeneration and reactive gliosis are prominent clinical features, we hypothesised that endogenous EphA4 could play a role in modulating EAE. EAE was induced in EphA4 knockout and wildtype mice using MOG peptide immunisation and clinical severity and histological features of the disease were then compared in lumbar spinal cord sections. EphA4 knockout mice exhibited a markedly less severe clinical course than wildtype mice, with a lower maximum disease grade and a slightly later onset of clinical symptoms. Numbers of infiltrating T cells and macrophages, the number and size of the lesions, and the extent of astrocytic gliosis were similar in both genotypes; however, EphA4 knockout mice appeared to have decreased axonal pathology. Blocking of EphA4 in wildtype mice by administration of soluble EphA4 (EphA4-Fc) as a decoy receptor following induction of EAE produced a delay in onset of clinical symptoms; however, most mice had clinical symptoms of similar severity by 22 days, indicating that EphA4 blocking treatment slowed early EAE disease evolution. Again there were no apparent differences in histopathology. To determine whether the role of EphA4 in modulating EAE was CNS mediated or due to an altered immune response, MOG primed T cells from wildtype and EphA4 knockout mice were passively transferred into naive recipient mice and both were shown to induce disease of equivalent severity. These results are consistent with a non-inflammatory, CNS specific, deleterious effect of EphA4 during neuroinflammation that results in axonal pathology. PMID:23390555

  1. Air pollution and stroke - an overview of the evidence base.

    PubMed

    Maheswaran, Ravi

    2016-08-01

    Air pollution is being increasingly recognized as a significant risk factor for stroke. There are numerous sources of air pollution including industry, road transport and domestic use of biomass and solid fuels. Early reports of the association between air pollution and stroke come from studies investigating health effects of severe pollution episodes. Several daily time series and case-crossover studies have reported associations with stroke. There is also evidence linking chronic air pollution exposure with stroke and with reduced survival after stroke. A conceptual framework linking air pollution exposure and stroke is proposed. It links acute and chronic exposure to air pollution with pathways to acute and chronic effects on stroke risk. Current evidence regarding potential mechanisms mainly relate to particulate air pollution. Whilst further evidence would be useful, there is already sufficient evidence to support consideration of reduction in air pollution as a preventative measure to reduce the stroke burden globally.

  2. Air pollution and stroke - an overview of the evidence base.

    PubMed

    Maheswaran, Ravi

    2016-08-01

    Air pollution is being increasingly recognized as a significant risk factor for stroke. There are numerous sources of air pollution including industry, road transport and domestic use of biomass and solid fuels. Early reports of the association between air pollution and stroke come from studies investigating health effects of severe pollution episodes. Several daily time series and case-crossover studies have reported associations with stroke. There is also evidence linking chronic air pollution exposure with stroke and with reduced survival after stroke. A conceptual framework linking air pollution exposure and stroke is proposed. It links acute and chronic exposure to air pollution with pathways to acute and chronic effects on stroke risk. Current evidence regarding potential mechanisms mainly relate to particulate air pollution. Whilst further evidence would be useful, there is already sufficient evidence to support consideration of reduction in air pollution as a preventative measure to reduce the stroke burden globally. PMID:27494962

  3. Acute isolated capsular stroke. A clinical study of 148 cases.

    PubMed

    Arboix, Adrià; Martínez-Rebollar, María; Oliveres, Montserrat; García-Eroles, Luis; Massons, Joan; Targa, Cecilia

    2005-02-01

    The objectives of the study were to assess differential features between capsular stroke of ischemic and hemorrhagic origin, and to compare capsular strokes with all other (non-capsular) strokes. Data of 148 patients with isolated capsular stroke were collected from a prospective hospital-based stroke registry in which 2000 consecutive acute stroke patients were included. Isolated capsular stroke accounted for 8.4% of strokes included in the registry (8.4% of ischemic strokes and 10.5% of intracerebral hemorrhages). Capsular stroke of hemorrhagic origin (n = 24) was more severe than ischemic capsular stroke (n = 124) as determined by a significantly higher in-hospital mortality, length of stay, and lower number of patients free of functional deficit at discharge. After multivariate analysis, limb weakness, sudden onset, and sensory symptoms were independently associated with capsular hemorrhage, whereas pure motor hemiparesis appeared to be associated with capsular infarction. In summary, one of each 12 patients with acute ischemic stroke and one of each 10 patients with acute intracerebral hemorrhage had an isolated capsular stroke. Lacunar syndrome was the most frequent clinical presentation being more common (particularly pure motor hemiparesis) in ischemic than in hemorrhagic capsular stroke. Capsular hemorrhage and capsular infarction showed identical risk factor profiles suggesting the same underlying vascular pathology for both conditions.

  4. Cardiorespiratory fitness after stroke: a systematic review.

    PubMed

    Smith, Alexandra C; Saunders, David H; Mead, Gillian

    2012-08-01

    Cardiorespiratory fitness programs are increasingly used in stroke rehabilitation. Maximal oxygen uptake is the gold standard measurement of cardiorespiratory fitness; however, no recent publications have collated evidence about maximal oxygen uptake levels following stroke. We therefore performed a systematic review of maximal oxygen uptake in stroke survivors, aiming to observe changes in levels over time, and associations with severity of stroke. We searched Medline and Embase until April 2011, and included cross-sectional studies, longitudinal studies, and baseline data from intervention trials. Studies had to recruit at least 10 stroke survivors, and report direct measurement of maximal/peak oxygen uptake. We then compared maximal oxygen uptake with published data from age and gender-matched controls. The search identified 3357 articles. Seventy-two full texts were retrieved, of which 41 met the inclusion criteria. Time since stroke ranged from 10 days to over seven-years. Peak oxygen uptake ranged from 8 to 22 ml/kg/min, which was 26-87% of that of healthy age- and gender-matched individuals. Stroke severity was mild in most studies. Three studies reported longitudinal changes; there was no clear evidence of change in peak oxygen uptake over time. Most studies recruited participants with mild stroke, and it is possible that cardiorespiratory fitness is even more impaired after severe stroke. Maximal oxygen uptake might have been overestimated, as less healthy and older stroke survivors may not tolerate maximal exercise testing. More studies are needed describing mechanisms of impaired cardiorespiratory fitness and longitudinal changes over time to inform the optimal 'prescription' of cardiorespiratory fitness programs for stroke survivors. PMID:22568786

  5. Effects of the magnitude of pressure on the severity of injury and capillary closure in rat experimental pressure ulcers.

    PubMed

    Kawamata, Seiichi; Kurose, Tomoyuki; Kubori, Yohei; Muramoto, Hiroaki; Honkawa, Yuta

    2015-03-01

    Experimental pressure ulcers were successfully produced in the rat abdominal wall at 100 mmHg in our previous study. We hypothesized that injury is less severe when pressures are lower than 100 mmHg and explored a critical pressure in the production of pressure ulcers. At 70 and 60 mmHg, repeated compressions for 4 h daily for 5 consecutive days resulted in partial skin necrosis and eschar formation in the majority of rats, whereas skin injuries were absent or very mild in most of the rats at 50 mmHg. The extent of ischemia was also examined by visualization of capillary blood flow using intravascular infusion of Lycopersicon esculentum lectin. Rat abdominal walls were compressed in the range from 0 (control) to 100 mmHg. The percentages of open capillaries were 62.8 ± 10.1% at 0 mmHg and 34.7 ± 18.5% at 10 mmHg. The ratio of open capillaries was further decreased with increasing pressure, but not pressure dependently. In conclusion, the severity of injury at 50 mmHg was drastically milder than that at 60 mmHg or higher, whereas the extent of ischemia (capillary closure) was not significantly different. The pressure is vitally important; however, other factor(s) besides ischemia is likely to promote the development of pressure ulcers. PMID:24676460

  6. Severity of Clinical Disease and Pathology in Ferrets Experimentally Infected with Influenza Viruses Is Influenced by Inoculum Volume

    PubMed Central

    Moore, Ian N.; Lamirande, Elaine W.; Paskel, Myeisha; Donahue, Danielle; Qin, Jing

    2014-01-01

    was administered at similar doses, different investigators reported a range of clinical disease outcomes, from asymptomatic infection to severe weight loss, ocular and nasal discharge, sneezing, and lethargy. We found that a wide range of inoculum volumes was used to experimentally infect ferrets, and we sought to determine whether the variations in disease outcome were the result of the volume of inoculum administered. These data highlight some less explored features of the model, methods of experimental infection, and clinical disease outcomes in a research setting. PMID:25187553

  7. The Impact of Cortical Lesions on Thalamo-Cortical Network Dynamics after Acute Ischaemic Stroke: A Combined Experimental and Theoretical Study

    PubMed Central

    van Wijngaarden, Joeri B. G.; Finnigan, Simon

    2016-01-01

    The neocortex and thalamus provide a core substrate for perception, cognition, and action, and are interconnected through different direct and indirect pathways that maintain specific dynamics associated with functional states including wakefulness and sleep. It has been shown that a lack of excitation, or enhanced subcortical inhibition, can disrupt this system and drive thalamic nuclei into an attractor state of low-frequency bursting and further entrainment of thalamo-cortical circuits, also called thalamo-cortical dysrhythmia (TCD). The question remains however whether similar TCD-like phenomena can arise with a cortical origin. For instance, in stroke, a cortical lesion could disrupt thalamo-cortical interactions through an attenuation of the excitatory drive onto the thalamus, creating an imbalance between excitation and inhibition that can lead to a state of TCD. Here we tested this hypothesis by comparing the resting-state EEG recordings of acute ischaemic stroke patients (N = 21) with those of healthy, age-matched control-subjects (N = 17). We observed that these patients displayed the hallmarks of TCD: a characteristic downward shift of dominant α-peaks in the EEG power spectra, together with increased power over the lower frequencies (δ and θ-range). Contrary to general observations in TCD, the patients also displayed a broad reduction in β-band activity. In order to explain the genesis of this stroke-induced TCD, we developed a biologically constrained model of a general thalamo-cortical module, allowing us to identify the specific cellular and network mechanisms involved. Our model showed that a lesion in the cortical component leads to sustained cell membrane hyperpolarization in the corresponding thalamic relay neurons, that in turn leads to the de-inactivation of voltage-gated T-type Ca2+-channels, switching neurons from tonic spiking to a pathological bursting regime. This thalamic bursting synchronises activity on a population level through

  8. The Impact of Cortical Lesions on Thalamo-Cortical Network Dynamics after Acute Ischaemic Stroke: A Combined Experimental and Theoretical Study.

    PubMed

    van Wijngaarden, Joeri B G; Zucca, Riccardo; Finnigan, Simon; Verschure, Paul F M J

    2016-08-01

    The neocortex and thalamus provide a core substrate for perception, cognition, and action, and are interconnected through different direct and indirect pathways that maintain specific dynamics associated with functional states including wakefulness and sleep. It has been shown that a lack of excitation, or enhanced subcortical inhibition, can disrupt this system and drive thalamic nuclei into an attractor state of low-frequency bursting and further entrainment of thalamo-cortical circuits, also called thalamo-cortical dysrhythmia (TCD). The question remains however whether similar TCD-like phenomena can arise with a cortical origin. For instance, in stroke, a cortical lesion could disrupt thalamo-cortical interactions through an attenuation of the excitatory drive onto the thalamus, creating an imbalance between excitation and inhibition that can lead to a state of TCD. Here we tested this hypothesis by comparing the resting-state EEG recordings of acute ischaemic stroke patients (N = 21) with those of healthy, age-matched control-subjects (N = 17). We observed that these patients displayed the hallmarks of TCD: a characteristic downward shift of dominant α-peaks in the EEG power spectra, together with increased power over the lower frequencies (δ and θ-range). Contrary to general observations in TCD, the patients also displayed a broad reduction in β-band activity. In order to explain the genesis of this stroke-induced TCD, we developed a biologically constrained model of a general thalamo-cortical module, allowing us to identify the specific cellular and network mechanisms involved. Our model showed that a lesion in the cortical component leads to sustained cell membrane hyperpolarization in the corresponding thalamic relay neurons, that in turn leads to the de-inactivation of voltage-gated T-type Ca2+-channels, switching neurons from tonic spiking to a pathological bursting regime. This thalamic bursting synchronises activity on a population level through

  9. Primary and Comprehensive Stroke Centers: History, Value and Certification Criteria

    PubMed Central

    2013-01-01

    In the United States (US) stroke care has undergone a remarkable transformation in the past decades at several levels. At the clinical level, randomized trials have paved the way for many new stroke preventives, and recently, several new mechanical clot retrieval devices for acute stroke treatment have been cleared for use in practice by the US Federal Drug Administration. Furthermore, in the mid 1990s we witnessed regulatory approval of intravenous recombinant tissue plasminogen activator for administration in acute ischemic stroke. In the domain of organization of medical care and delivery of health services, stroke has transitioned from a disease dominated by neurologic consultation services only to one managed by vascular neurologists in geographical stroke units, stroke teams and care pathways, primary stroke center certification according to The Joint Commission, and most recently comprehensive stroke center designation under the aegis of The Joint Commission. Many organizations in the US have been involved to enhance stroke care. To name a few, the American Heart Association/American Stroke Association, Brain Attack Coalition, and National Stroke Association have been on the forefront of this movement. Additionally, governmental initiatives by the US Centers for Disease Control and Prevention and legislative initiatives such as the Paul Coverdell National Acute Stroke Registry program have paved the way to focus on stroke prevention, acute treatment and quality improvement. In this invited review, we discuss a brief history of organized stroke care in the United States, evidence to support the value of primary and comprehensive stroke centers, and the certification criteria and process to become a primary or comprehensive stroke center. PMID:24324943

  10. Modeling Dynamic Regulatory Processes in Stroke.

    SciTech Connect

    McDermott, Jason E.; Jarman, Kenneth D.; Taylor, Ronald C.; Lancaster, Mary J.; Shankaran, Harish; Vartanian, Keri B.; Stevens, S.L.; Stenzel-Poore, Mary; Sanfilippo, Antonio P.

    2012-10-11

    The ability to examine in silico the behavior of biological systems can greatly accelerate the pace of discovery in disease pathologies, such as stroke, where in vivo experimentation is lengthy and costly. In this paper we describe an approach to in silico examination of blood genomic responses to neuroprotective agents and subsequent stroke through the development of dynamic models of the regulatory processes observed in the experimental gene expression data. First, we identified functional gene clusters from these data. Next, we derived ordinary differential equations (ODEs) relating regulators and functional clusters from the data. These ODEs were used to develop dynamic models that simulate the expression of regulated functional clusters using system dynamics as the modeling paradigm. The dynamic model has the considerable advantage of only requiring an initial starting state, and does not require measurement of regulatory influences at each time point in order to make accurate predictions. The manipulation of input model parameters, such as changing the magnitude of gene expression, made it possible to assess the behavior of the networks through time under varying conditions. We report that an optimized dynamic model can provide accurate predictions of overall system behavior under several different preconditioning paradigms.

  11. [Neglect rehabilitation after stroke].

    PubMed

    Jehkonen, Mervi; Yliranta, Aino; Rasimus, Susanna; Saunamäki, Tiia

    2013-01-01

    Neglect is a common neuropsychological disorder after right hemisphere stroke. Neglect worsens the prognosis of functional recovery but responds well to targeted neuropsychological rehabilitation. Several methods for rehabilitation have been developed and research to-date lends best support to visual scanning training, prism adaptation, limb activation and feedback training. Core features of effective neglect rehabilitation include early initiation, daily held sessions at acute and subacute stages, increasing awareness of deficit and considering the psychosocial status of the patient as well as that of the family.

  12. [Sports and heat stroke].

    PubMed

    Yuzawa, Itsuki; Miyake, Yasufumi; Aruga, Tohru

    2012-06-01

    We described Characteristic of the heat stroke in the sports activity in Japan. It was common in teenage men, and 15 years old had a peak with a man, the woman. Most patients did not need specific treatment. Many happened from the end of July on the outdoors around 3:00 p.m. in mid-August. There are many in order of baseball, football, tennis, and a basketball. Running and cycling had high severity of illness. Probably, grasp of an environmental condition, suitable sportswear, suitable hydration, and condition management are the best things as preventive measures.

  13. Severity of Locomotor and Cardiovascular Derangements after Experimental High-Thoracic Spinal Cord Injury Is Anesthesia Dependent in Rats

    PubMed Central

    Beattie, Michael S.; Bresnahan, Jacqueline C.

    2012-01-01

    Abstract Anesthetics affect outcomes from central nervous system (CNS) injuries differently. This is the first study to show how two commonly used anesthetics affect continuously recorded hemodynamic parameters and locomotor recovery during a 2-week period after two levels of contusion spinal cord injury (SCI) in rats. We hypothesized that the level of cardiovascular depression and recovery of locomotor function would be dependent upon the anesthetic used during SCI. Thirty-two adult female rats were subjected to a sham, 25-mm or 50-mm SCI at T3–4 under pentobarbital or isoflurane anesthesia. Mean arterial pressure (MAP) and heart rate (HR) were telemetrically recorded before, during, and after SCI. Locomotor function recovered best in the 25-mm-injured isoflurane-anesthetized animals. There was no significant difference in locomotor recovery between the 25-mm-injured pentobarbital-anesthetized animals and the 50-mm-injured isoflurane-anesthetized animals. White matter sparing and extent of intermediolateral cell column loss appeared larger in animals anesthetized with pentobarbital, but this was not significant. There were no differential effects of anesthetics on HR and MAP before SCI, but recovery from anesthesia was significantly slower in pentobarbital-anesthetized animals. At the time of SCI, MAP was acutely elevated in the pentobarbital-anesthetized animals, whereas MAP decreased in the isoflurane-anesthetized animals. Hypotension occurred in the pentobarbital-anesthetized groups and in the 50-mm-injured isoflurane-anesthetized group. In pentobarbital-anesthetized animals, SCI resulted in acute elevation of HR, although HR remained low. Return of HR to baseline was much slower in the pentobarbital-anesthetized animals. Severe SCI at T3 produced significant chronic tachycardia that was injury severity dependent. Although some laboratories monitor blood pressure, HR, and other physiological variables during surgery for SCI, inherently few have monitored

  14. Stroke Associated with Atrial Fibrillation – Incidence and Early Outcomes in the North Dublin Population Stroke Study

    PubMed Central

    Hannon, Niamh; Sheehan, Orla; Kelly, Lisa; Marnane, Michael; Merwick, Aine; Moore, Alan; Kyne, Lorraine; Duggan, Joseph; Moroney, Joan; McCormack, Patricia M.E.; Daly, Leslie; Fitz-Simon, Nicola; Harris, Dawn; Horgan, Gillian; Williams, Emma B.; Furie, Karen L.; Kelly, Peter J.

    2009-01-01

    Background Prospective population-based studies are important to accurately determine the incidence and characteristics of stroke associated with atrial fibrillation (AF), while avoiding selection bias which may complicate hospital-based studies. Methods We investigated AF-associated stroke within the North Dublin Population Stroke Study, a prospective cohort study of stroke/transient ischaemic attack in 294,592 individuals, according to recommended criteria for rigorous stroke epidemiological studies. Results Of 568 stroke patients ascertained in the first year, 31.2% (177/568) were associated with AF (90.4%, i.e. 160/177 ischaemic infarcts). The crude incidence rate of all AF-associated stroke was 60/100,000 person-years (95% CI = 52–70). Prior stroke was almost twice as common in AF compared to non-AF groups (21.9 vs. 12.8%, p = 0.01). The frequency of AF progressively increased across ischaemic stroke patients stratified by increasing stroke severity (NIHSS 0–4, 29.7%; 5–9, 38.1%; 10–14, 43.8%; ≥15, 53.3%, p < 0.0001). The 90-day trajectory of recovery of AF-associated stroke was identical to that of non-AF stroke, but Rankin scores in AF stroke remained higher at 7, 28 and 90 days (p < 0.001 for all). Discussion: AF-associated stroke occurred in one third of all patients and was associated with a distinct profile of recurrent, severe and disabling stroke. Targeted strategies to increase anticoagulation rates may provide a substantial benefit to prevent severe disabling stroke at a population level. PMID:19893311

  15. Clinical study of 222 patients with pure motor stroke

    PubMed Central

    Arboix, A; Padilla, I; Massons, J; Garcia-Eroles, L; Comes, E; Targa, C

    2001-01-01

    The objective was to assess the frequency of pure motor stroke caused by different stroke subtypes and to compare demographic, clinical, neuroimaging, and outcome data of pure motor stroke with those of patients with other lacunar stroke as well as with those of patients with non-lacunar stroke.
Data from 2000 patients with acute stroke (n=1761) or transient ischaemic attack (n=239) admitted consecutively to the department of neurology of an acute care 350 bed teaching hospital were prospectively collected in the Sagrat Cor Hospital of Barcelona stroke registry over a 10 year period. For the purpose of the study 222 (12.7%) patients with pure motor stroke were selected. The other study groups included 218 (12.3%) patients with other lacunar strokes and 1321 (75%) patients with non-lacunar stroke.
In relation to stroke subtype, lacunar infarcts were found in 189 (85%) patients, whereas ischaemic lacunar syndromes not due to lacunar infarcts occurred in 23 (10.4%) patients (atherothrombotic stroke in 12, cardioembolic stroke in seven, infarction of undetermined origin in three, and infarction of unusual aetiology in one) and haemorrhagic lacunar syndromes in 10 (4.5%). Patients with pure motor stroke showed a better outcome than patients with non-lacunar stroke with a significantly lower number of complications and in hospital mortality rate, shorter duration of hospital stay, and a higher number of symptom free patients at hospital discharge. After multivariate analysis, hypertension, diabetes, obesity, hyperlipidaemia, non-sudden stroke onset, internal capsule involvement, and pons topography seemed to be independent factors of pure motor stroke in patients with acute stroke.
In conclusion, about one of every 10 patients with acute stroke had a pure motor stroke. Pure motor stroke was caused by a lacunar infarct in 85% of patients and by other stroke subtypes in 15%. Several clinical features are more frequent in patients with pure motor stroke than in

  16. Stroke and migraine is there a possible comorbidity?

    PubMed

    Spalice, Alberto; Del Balzo, Francesca; Papetti, Laura; Zicari, Anna Maria; Properzi, Enrico; Occasi, Francesca; Nicita, Francesco; Duse, Marzia

    2016-04-26

    The association between migraine and stroke is still a dilemma for neurologists. Migraine is associated with an increased stroke risk and it is considered an independent risk factor for ischaemic stroke in a particular subgroup of patients. The pathogenesis is still unknown even if several studies report some common biochemical mechanisms between these two diseases. A classification of migraine-related stroke that encompasses the full spectrum of the possible relationship between migraine and stroke includes three main entities: coexisting stroke and migraine, stroke with clinical features of migraine, and migraine-induced stroke. The concept of migraine-induced stroke is well represented by migrainous infarction and it is described in the revised classification of the International Headache Society (IHS), representing the strongest demonstration of the relationship between ischaemic stroke and migraine. A very interesting common condition in stroke and migraine is patent foramen ovale (PFO) which could play a pathogenetic role in both disorders. The neuroradiological evidence of subclinical lesions most typical in the white matter and in the posterior artery territories in patients with migraine, opens a new field of research. In conclusion the association between migraine and stroke remains an open question. Solving the above mentioned issues is fundamental to understand the epidemiologic, pathogenetic and clinical aspects of migraine-related stroke.

  17. Stroke rehabilitation in Canada: a work in progress.

    PubMed

    Teasell, Robert; Meyer, Matthew J; Foley, Norine; Salter, Katherine; Willems, Deb

    2009-01-01

    Stroke rehabilitation in Canada continues to function under models and practices that have changed little in the last four decades and struggles to implement new evidence-based or best practices. Ontario, Canada's largest province, has had a coordinated stroke strategy since 2000. The Ontario Stroke System has developed an extensive infrastructure of research syntheses, consensus panel recommendations, practice guidelines, standards of care, and centralized data collection across the continuum of stroke care. This has produced a solid foundation upon which an evidence-based stroke rehabilitation system can be developed. However, failure to invest in stroke rehabilitation or provide incentives to implement change has resulted in the stroke rehabilitation system and critical outcomes remaining largely unchanged. Improvements in time to admission have been countered by rising admission FIM scores such that severe stroke patients often cannot access the stroke rehabilitation system. Many stroke patients are still rehabilitated on general rehabilitation units, therapy intensities remain unacceptably low, and many outpatient programs are being reduced or even closed. Although there are pockets of innovation, the stroke rehabilitation system continues to function more according to traditional ways of practicing. The hope is that with appropriate investments and incentives, Canadians and Ontarians can build upon the existing infrastructure to ensure stroke patients receive optimal rehabilitative care based on best evidence. In the meantime, stroke rehabilitation in Canada remains a work in progress.

  18. RSV-specific airway resident memory CD8+ T cells and differential disease severity after experimental human infection

    PubMed Central

    Jozwik, Agnieszka; Habibi, Maximillian S.; Paras, Allan; Zhu, Jie; Guvenel, Aleks; Dhariwal, Jaideep; Almond, Mark; Wong, Ernie H. C.; Sykes, Annemarie; Maybeno, Matthew; Del Rosario, Jerico; Trujillo-Torralbo, Maria-Belen; Mallia, Patrick; Sidney, John; Peters, Bjoern; Kon, Onn Min; Sette, Alessandro; Johnston, Sebastian L.; Openshaw, Peter J.; Chiu, Christopher

    2015-01-01

    In animal models, resident memory CD8+ T (Trm) cells assist in respiratory virus elimination but their importance in man has not been determined. Here, using experimental human respiratory syncytial virus (RSV) infection, we investigate systemic and local virus-specific CD8+ T-cell responses in adult volunteers. Having defined the immunodominance hierarchy, we analyse phenotype and function longitudinally in blood and by serial bronchoscopy. Despite rapid clinical recovery, we note surprisingly extensive lower airway inflammation with persistent viral antigen and cellular infiltrates. Pulmonary virus-specific CD8+ T cells display a CD69+CD103+ Trm phenotype and accumulate to strikingly high frequencies into convalescence without continued proliferation. While these have a more highly differentiated phenotype, they express fewer cytotoxicity markers than in blood. Nevertheless, their abundance before infection correlates with reduced symptoms and viral load, implying that CD8+ Trm cells in the human lung can confer protection against severe respiratory viral disease when humoral immunity is overcome. PMID:26687547

  19. Pathophysiology and Treatments of Oxidative Injury in Ischemic Stroke: Focus on the Phagocytic NADPH Oxidase 2

    PubMed Central

    Carbone, Federico; Teixeira, Priscila Camillo; Braunersreuther, Vincent; Mach, François; Vuilleumier, Nicolas

    2015-01-01

    Abstract Significance: Phagocytes play a key role in promoting the oxidative stress after ischemic stroke occurrence. The phagocytic NADPH oxidase (NOX) 2 is a membrane-bound enzyme complex involved in the antimicrobial respiratory burst and free radical production in these cells. Recent Advances: Different oxidants have been shown to induce opposite effects on neuronal homeostasis after a stroke. However, several experimental models support the detrimental effects of NOX activity (especially the phagocytic isoform) on brain recovery after stroke. Therapeutic strategies selectively targeting the neurotoxic ROS and increasing neuroprotective oxidants have recently produced promising results. Critical Issues: NOX2 might promote carotid plaque rupture and stroke occurrence. In addition, NOX2-derived reactive oxygen species (ROS) released by resident and recruited phagocytes enhance cerebral ischemic injury, activating the inflammatory apoptotic pathways. The aim of this review is to update evidence on phagocyte-related oxidative stress, focusing on the role of NOX2 as a potential therapeutic target to reduce ROS-related cerebral injury after stroke. Future Directions: Radical scavenger compounds (such as Ebselen and Edaravone) are under clinical investigation as a therapeutic approach against stroke. On the other hand, NOX inhibition might represent a promising strategy to prevent the stroke-related injury. Although selective NOX inhibitors are not yet available, nonselective compounds (such as apocynin and fasudil) provided encouraging results in preclinical studies. Whereas additional studies are needed to better evaluate this therapeutic potential in human beings, the development of specific NOX inhibitors (such as monoclonal antibodies, small-molecule inhibitors, or aptamers) might further improve brain recovery after stroke. Antioxid. Redox Signal. 23, 460–489. PMID:24635113

  20. Long-term cognitive outcomes after pediatric stroke.

    PubMed

    Kolk, Anneli; Ennok, Margus; Laugesaar, Rael; Kaldoja, Mari-Liis; Talvik, Tiina

    2011-02-01

    This study assessed neurocognitive and neurologic outcomes of children with neonatal and childhood strokes. Twenty-one children with neonatal (mean age, 6.86 years) and 10 children with childhood (mean age, 8.21 years) strokes, identified via the Estonian Pediatric Stroke Database (1995-2006), participated. A developmental neuropsychologic assessment was used for neurocognitive outcomes, and the Paediatric Stroke Outcome Measure for neurologic outcomes. Neuromotor impairment was evident in 62% of children with neonatal strokes, and in 70% of children with childhood strokes. Compared with control subjects, children with strokes exhibited worse attention, language, memory, and sensorimotor functions. The sensorimotor domain comprised the most impaired neurocognitive area, whereas executive functions remained intact in both stroke groups. A well-preserved executive function may account for the normal range of intelligence in children with strokes. More severe impairment in neurocognitive skills was evident after neonatal strokes, and the visuospatial domain was more impaired than in children from the childhood group. Prognoses were worse after left hemisphere strokes associated with epilepsy. Our results on emerging neurocognitive deficits in several areas underline the importance of neuropsychologic testing and the follow-up of children with pediatric strokes. PMID:21215909

  1. Cerebral ischemic stroke: is gender important?

    PubMed Central

    Gibson, Claire L

    2013-01-01

    Cerebral stroke continues to be a major cause of death and the leading cause of long-term disability in developed countries. Evidence reviewed here suggests that gender influences various aspects of the clinical spectrum of ischemic stroke, in terms of influencing how a patients present with ischemic stroke through to how they respond to treatment. In addition, this review focuses on discussing the various pathologic mechanisms of ischemic stroke that may differ according to gender and compares how intrinsic and hormonal mechanisms may account for such gender differences. All clinical trials to date investigating putative neuroprotective treatments for ischemic stroke have failed, and it may be that our understanding of the injury cascade initiated after ischemic injury is incomplete. Revealing aspects of the pathophysiological consequences of ischemic stroke that are gender specific may enable gender relevant and effective neuroprotective strategies to be identified. Thus, it is possible to conclude that gender does, in fact, have an important role in ischemic stroke and must be factored into experimental and clinical investigations of ischemic stroke. PMID:23756694

  2. [Stroke and aging].

    PubMed

    Ly, J; Maquet, P

    2014-01-01

    Stroke risk increases with aging and one third of ischemic strokes occurs in very elderly (> or = 80 years). These are responsible of two thirds of the overall stroke-related morbi-mortality. Stroke in very elderly differs from younger individuals by sex ratio (more women), risk factors (more atrial fibrillation and hypertension) and usually a worse functional outcome. Very elderly are likely to benefit from stroke unit care and early revascularisation treatments although they have historically been excluded from this urgent management. These issues are likely to worsen in the future with the increasing impact of stroke on our aging societies.

  3. How a Stroke Is Diagnosed

    MedlinePlus

    ... Trials News About Neurology Image Library Search The Internet Stroke Center Patients & Families About Stroke Stroke Diagnosis ... UT Southwestern Medical Center. Copyright © 1997-2016 - The Internet Stroke Center. All rights reserved. The information contained ...

  4. Questions and Answers about Stroke

    MedlinePlus

    ... 30 percent are permanently disabled. What is the cost of stroke for our nation? Stroke places a ... society in terms of mortality, morbidity and economic costs. The National Stroke Association estimates stroke costs the ...

  5. Cardioembolic Stroke and Postmyocardial Infarction Stroke.

    PubMed

    Hornung, Marius; Franke, Jennifer; Gafoor, Sameer; Sievert, Horst

    2016-05-01

    Ischemic stroke following acute myocardial infarction (AMI) is a rare but serious complication due to left ventricular thrombus formation and atrial fibrillation. Early revascularization of the culprit coronary lesion is essential. Treatment trends may affect the risk. Conversely, the greater use of antiplatelet agents to reduce the risk of ischemic stroke could increase the risk of hemorrhagic stroke. The risk of stroke after AMI has decreased significantly with more use of percutaneous coronary intervention and antithrombotic therapies in the acute setting, and statins, antihypertensive medications, and dual antiplatelet therapy as secondary prevention strategies. PMID:27150168

  6. Reduction of zinc accumulation in mitochondria contributes to decreased cerebral ischemic injury by normobaric hyperoxia treatment in an experimental stroke model.

    PubMed

    Dong, Wen; Qi, Zhifeng; Liang, Jia; Shi, Wenjuan; Zhao, Yongmei; Luo, Yumin; Ji, Xunming; Liu, Ke Jian

    2015-10-01

    Cerebral ischemia interrupts oxygen supply to the affected tissues. Our previous studies have reported that normobaric hyperoxia (NBO) can maintain interstitial partial pressure of oxygen (pO2) in the penumbra of ischemic stroke rats at the physiological level, thus affording significant neuroprotection. However, the mechanisms that are responsible for the penumbra rescue by NBO treatment are not fully understood. Recent studies have shown that zinc, an important mediator of intracellular and intercellular neuronal signaling, accumulates in neurons and leads to ischemic neuronal injury. In this study, we investigate whether NBO could regulate zinc accumulation in the penumbra and prevent mitochondrial damage in penumbral tissue using a transient cerebral ischemic rat model. Our results showed that NBO significantly reduced zinc-staining positive cells and zinc-staining intensity in penumbral tissues, but not in the ischemic core. Moreover, ischemia-induced zinc accumulation in mitochondria, isolated from penumbral tissues, was greatly attenuated by NBO or a zinc-specific chelator, N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN). NBO or TPEN administration stabilized the mitochondrial membrane potential in the penumbra after cerebral ischemia. Finally, ischemia-induced cytochrome c release from mitochondria in penumbral tissues was significantly reduced by NBO or TPEN treatment. These findings demonstrate a novel mechanism for NBO's neuroprotection, especially to penumbral tissues, providing further evidence for the potential clinical benefit of NBO for acute ischemic stroke.

  7. Towards brain-robot interfaces in stroke rehabilitation.

    PubMed

    Gomez-Rodriguez, M; Grosse-Wentrup, M; Hill, J; Gharabaghi, A; Scholkopf, B; Peters, J

    2011-01-01

    A neurorehabilitation approach that combines robot-assisted active physical therapy and Brain-Computer Interfaces (BCIs) may provide an additional mileage with respect to traditional rehabilitation methods for patients with severe motor impairment due to cerebrovascular brain damage (e.g., stroke) and other neurological conditions. In this paper, we describe the design and modes of operation of a robot-based rehabilitation framework that enables artificial support of the sensorimotor feedback loop. The aim is to increase cortical plasticity by means of Hebbian-type learning rules. A BCI-based shared-control strategy is used to drive a Barret WAM 7-degree-of-freedom arm that guides a subject's arm. Experimental validation of our setup is carried out both with healthy subjects and stroke patients. We review the empirical results which we have obtained to date, and argue that they support the feasibility of future rehabilitative treatments employing this novel approach. PMID:22275589

  8. Delayed ethyl pyruvate therapy attenuates experimental severe acute pancreatitis via reduced serum high mobility group box 1 levels in rats

    PubMed Central

    Yang, Zhi-Yong; Ling, Yan; Yin, Tao; Tao, Jing; Xiong, Jiong-Xin; Wu, He-Shui; Wang, Chun-You

    2008-01-01

    AIM: To investigate the effect of delayed ethyl pyruvate (EP) delivery on distant organ injury, survival time and serum high mobility group box 1 (HMGB1) levels in rats with experimental severe acute pancreatitis (SAP). METHODS: A SAP model was induced by retrograde injection of artificial bile into the pancreatic ducts of rats. Animals were divided randomly into three groups (n = 32 in each group): sham group, SAP group and delayed EP treatment group. The rats in the delayed EP treatment group received EP (30 mg/kg) at 12 h, 18 h and 30 h after induction of SAP. Animals were sacrificed, and samples were obtained at 24 h and 48 h after induction of SAP. Serum HMGB1, aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), and creatinine (Cr) levels were measured. Lung wet-to-dry-weight (W/D) ratios and histological scores were calculated to evaluate lung injury. Additional experiments were performed between SAP and delayed EP treatment groups to study the influence of EP on survival times of SAP rats. RESULTS: Delayed EP treatment significantly reduced serum HMGB1 levels, and protected against liver, renal and lung injury with reduced lung W/D ratios (8.22 ± 0.42 vs 9.76 ± 0.45, P < 0.01), pulmonary histological scores (7.1 ± 0.7 vs 8.4 ± 1.1, P < 0.01), serum AST (667 ± 103 vs 1 368 ± 271, P < 0.01), ALT (446 ± 91 vs 653 ± 98, P < 0.01) and Cr (1.2 ± 0.3 vs 1.8 ± 0.3, P < 0.01) levels. SAP rats had a median survival time of 44 h. Delayed EP treatment significantly prolonged median survival time to 72 h (P < 0.01). CONCLUSION: Delayed EP therapy protects against distant organ injury and prolongs survival time via reduced serum HMGB1levels in rats with experimental SAP. EP may potentially serve as an effective new therapeutic option against the inflammatory response and multiple organ dysfunction syndrome (MODS) in SAP patients. PMID:18680237

  9. Increased oxidative stress and severe arterial remodeling induced by permanent high-flow challenge in experimental pulmonary hypertension

    PubMed Central

    2011-01-01

    Background Involvement of inflammation in pulmonary hypertension (PH) has previously been demonstrated and recently, immune-modulating dendritic cells (DCs) infiltrating arterial lesions in patients suffering from idiopathic pulmonary arterial hypertension (IPAH) and in experimental monocrotaline-induced PH have been reported. Occurrence of perivascular inflammatory cells could be linked to local increase of oxidative stress (OS), as it has been shown for systemic atherosclerosis. The impact of OS on vascular remodeling in PH is still to be determined. We hypothesized, that augmented blood-flow could increase OS and might thereby contribute to DC/inflammatory cell-recruitment and smooth-muscle-cell-proliferation. Methods We applied a monocrotaline-induced PH-model and combined it with permanent flow-challenge. Thirty Sprague-Dawley rats were assigned to following groups: control, monocrotaline-exposure (MCT), monocrotaline-exposure/pneumonectomy (MCT/PE). Results Hemodynamic exploration demonstrated most severe effects in MCT/PE, corresponding in histology to exuberant medial and adventitial remodeling of pulmonary muscular arteries, and intimal remodeling of smaller arterioles; lung-tissue PCR evidenced increased expression of DCs-specific fascin, CD68, proinflammatory cytokines (IL-6, RANTES, fractalkine) in MCT/PE and to a lesser extent in MCT. Major OS enzyme NOX-4 was maximal in MCT/PE. Antioxidative stress enzymes Mn-SOD and glutathion-peroxidase-1 were significantly elevated, while HO-1 showed maximal expression in MCT with significant decrease in MCT/PE. Catalase was decreased in MCT and MCT/PE. Expression of NOX-4, but also of MN-SOD in MCT/PE was mainly attributed to a highly increased number of interstitial and perivascular CXCR4/SDF1 pathway-recruited mast-cells. Stress markers malonedialdehyde and nitrotyrosine were produced in endothelial cells, medial smooth muscle and perivascular leucocytes of hypertensive vasculature. Immunolabeling for OX62, CD68

  10. The association of migraine with ischemic stroke.

    PubMed

    Kurth, Tobias

    2010-03-01

    Migraine is a common, chronic-intermittent primary headache disorder affecting mostly women. The migraine pathophysiology involves both the neuronal and vascular systems, and in some patients, transient neurologic symptoms occur, which are known as migraine aura. A large body of literature supports an association between migraine and ischemic stroke, which is apparent mostly in young women with migraine with aura. Further increased risks have been observed particularly in smokers and women who use oral contraceptives. The vast majority of individual studies, as well as a recent meta-analysis, did not find an association between migraine without aura and ischemic stroke. Although there are several hypotheses about potential biological mechanisms linking migraine with aura to ischemic stroke, the precise causes remain unclear. Because the absolute risk of stroke is considerably low in patients with migraine, the vast majority of migraine patients will not experience a stroke event because of the migraine.

  11. Stroke program for India

    PubMed Central

    Mishra, Nishant K.; Khadilkar, Satish V.

    2010-01-01

    India is silently witnessing a stroke epidemic. There is an urgent need to develop a national program towards “Fighting Stroke”. This program should be specific to our national needs. In order to recommend on who should lead an Indian fight-stroke program, we examined the published opinions of stroke clinicians and the official documents on stroke care training abroad. We identified the resources that already exist in India and can be utilized to develop a national fight-stroke program. Through a review of published literature, we noted different opinions that exist on who would best manage stroke. We found that because stroke is a cardiovascular disorder of the central nervous system, its management requires a multi-disciplinary approach involving clinicians with background not limited to neurology. India has very few neurologists trained in stroke medicine and they cannot care for all stroke patients of the country. We propose a mechanism that would quickly put in place a stroke care model relevant in Indian context. We recommend for tapping the clinical expertise available from existing pool of non-neurologist physicians who can be trained and certified in stroke medicine (Strokology). We have discussed an approach towards developing a national network for training and research in Strokology hoping that our recommendations would initiate discussion amongst stroke academicians and motivate the national policy makers to quickly develop an “Indian Fight Stroke Program.” PMID:20436743

  12. Matrix metalloproteinase 9-induced increase in intestinal epithelial tight junction permeability contributes to the severity of experimental DSS colitis.

    PubMed

    Nighot, Prashant; Al-Sadi, Rana; Rawat, Manmeet; Guo, Shuhong; Watterson, D Martin; Ma, Thomas

    2015-12-15

    Recent studies have implicated a pathogenic role for matrix metalloproteinases 9 (MMP-9) in inflammatory bowel disease. Although loss of epithelial barrier function has been shown to be a key pathogenic factor for the development of intestinal inflammation, the role of MMP-9 in intestinal barrier function remains unclear. The aim of this study was to investigate the role of MMP-9 in intestinal barrier function and intestinal inflammation. Wild-type (WT) and MMP-9(-/-) mice were subjected to experimental dextran sodium sulfate (DSS) colitis by administration of 3% DSS in drinking water for 7 days. The mouse colonic permeability was measured in vivo by recycling perfusion of the entire colon using fluorescently labeled dextran. The DSS-induced increase in the colonic permeability was accompanied by an increase in intestinal epithelial cell MMP-9 expression in WT mice. The DSS-induced increase in intestinal permeability and the severity of DSS colitis was found to be attenuated in MMP-9(-/-) mice. The colonic protein expression of myosin light chain kinase (MLCK) and phospho-MLC was found to be significantly increased after DSS administration in WT mice but not in MMP-9(-/-) mice. The DSS-induced increase in colonic permeability and colonic inflammation was attenuated in MLCK(-/-) mice and MLCK inhibitor ML-7-treated WT mice. The DSS-induced increase in colonic surface epithelial cell MLCK mRNA was abolished in MMP-9(-/-) mice. Lastly, increased MMP-9 protein expression was detected within the colonic surface epithelial cells in ulcerative colitis cases. These data suggest a role of MMP-9 in modulation of colonic epithelial permeability and inflammation via MLCK.

  13. Transcranial Direct Current Stimulation in Stroke Recovery

    PubMed Central

    Schlaug, Gottfried; Renga, Vijay; Nair, Dinesh

    2009-01-01

    TDCS - Transcranial Direct Current Stimulation - is an emerging technique of non-invasive brain stimulation that has been found useful in examining cortical function in normal subjects and in facilitating treatments of various neurological disorders. A better understanding of adaptive as well as maladaptive post-stroke neuroplasticity and its modulation through non-invasive brain stimulation has opened up experimental treatment options using TDCS for patients recovering from stroke. We will review TDCS’s role as a facilitator of stroke recovery, the different modes of transcranial direct current stimulation, and the potential mechanisms underlying the neural effects of TDCS. PMID:19064743

  14. Stroke: Hope through Research

    MedlinePlus

    ... substantially reduce costs of care. Stroke Hyperglycemia Insulin Network Effort Trial (SHINE) Nearly 40 percent of patients ... Stroke, contact the Institute's Brain Resources and Information Network (BRAIN) at: BRAIN P.O. Box 5801 Bethesda, ...

  15. Stroke Trials Registry

    MedlinePlus

    ... Trials News About Neurology Image Library Search The Internet Stroke Center Trials Registry Clinical Trials Interventions Conditions ... UT Southwestern Medical Center. Copyright © 1997-2011 - The Internet Stroke Center. All rights reserved. The information contained ...

  16. Stroke (For Kids)

    MedlinePlus

    ... is a mix of cholesterol and other fatty stuff that sticks to the walls of blood vessels. ... major stroke can cause big problems with important stuff, like walking and talking. With a major stroke, ...

  17. Two Kinds of Stroke

    MedlinePlus

    ... repair itself to restore important functions after a stroke. New advances in imaging and rehabilitation have shown that the brain can compensate for function lost as a result of stroke. Summer 2007 Issue: Volume 2 Number 3 Page ...

  18. Stroke Fact Sheet

    MedlinePlus

    ... tells you to. Return to top Does taking birth control pills increase my risk for stroke? Taking birth ... your vagina Return to top Does using the birth control patch increase my risk for stroke? The patch ...

  19. The assessment of visuo-spatial neglect after acute stroke.

    PubMed Central

    Stone, S P; Wilson, B; Wroot, A; Halligan, P W; Lange, L S; Marshall, J C; Greenwood, R J

    1991-01-01

    Forty four consecutive patients with acute hemispheric stroke and forty seven elderly controls with no neurological disease were assessed for visuo-spatial neglect, using a modified neglect test battery. Neglect was found to be equally common in patients with right hemisphere and left hemisphere stroke three days after stroke (72% versus 62%). It was more severe in those with a right hemisphere stroke and resolved more frequently in those with a left hemisphere stroke. The battery was validated against an occupational therapist's assessment of neglect on self-care tasks. The inter-observer reliability was good and it was possible to monitor changes over time with the battery. Images PMID:2056321

  20. Promoting endothelial function by S-nitrosoglutathione through the HIF-1α/VEGF pathway stimulates neurorepair and functional recovery following experimental stroke in rats

    PubMed Central

    Khan, Mushfiquddin; Dhammu, Tajinder S; Matsuda, Fumiyo; Baarine, Mauhammad; Dhindsa, Tejbir Singh; Singh, Inderjit; Singh, Avtar K

    2015-01-01

    Background For stroke patients, stimulating neurorepair mechanisms is necessary to reduce morbidity and disability. Our previous studies on brain and spinal cord trauma show that exogenous treatment with the S-nitrosylating agent S-nitrosoglutathione (GSNO) – a nitric oxide and glutathione metabolite of the human body – stimulates neurorepair and aids functional recovery. Using a rat model of cerebral ischemia and reperfusion (IR) in this study, we tested the hypothesis that GSNO invokes the neurorepair process and improves neurobehavioral functions through the angiogenic HIF-1α/VEGF pathway. Methods Stroke was induced by middle cerebral artery occlusion for 60 minutes followed by reperfusion in adult male rats. The injured animals were treated with saline (IR group, n=7), GSNO (0.25 mg/kg, GSNO group, n=7), and GSNO plus the HIF-1α inhibitor 2-methoxyestra-diol (2-ME) (0.25 mg/kg GSNO + 5.0 mg/kg 2-ME, GSNO + 2-ME group, n=7). The groups were studied for either 7 or 14 days to determine neurorepair mediators and functional recovery. Brain capillary endothelial cells were used to show that GSNO promotes angiogenesis and that GSNO-mediated induction of VEGF and the stimulation of angiogenesis are dependent on HIF-1α activity. Results IR injury increased the expression of neurorepair mediators HIF-1α, VEGF, and PECAM-1 and vessel markers to a limited degree that correlate well with significantly compromised neurobehavioral functions compared with sham animals. GSNO treatment of IR not only remarkably enhanced further the expression of HIF-1α, VEGF, and PECAM-1 but also improved functioning compared with IR. The GSNO group also had a higher degree of vessel density than the IR group. Increased expression of VEGF and the degree of tube formation (angiogenesis) by GSNO were reduced after the inhibition of HIF-1α by 2-ME in an endothelial cell culture model. 2-ME treatment of the GSNO group also blocked not only GSNO’s effect of reduced infarct volume

  1. [Stroke and neuroplasticity].

    PubMed

    Damulin, I V; Ekusheva, E V

    2014-01-01

    Characteristics of stroke development and processes of restoration of brain function in post stroke period are considered. The dynamics of neuroplasticity and ambiguity of the involvement of the opposite brain hemisphere in the restoration is highlighted. Special attention is drawn to the time from stroke onset and activation of different brain regions in post stroke period. The importance of neurorehabilitation in these patients is emphasized.

  2. Ischemic Strokes: Observations from a Hospital Based Stroke Registry in Bangladesh

    PubMed Central

    Saifuddin, Mohammad; Islam, Md. Rashedul; Habib, Rumana; Rahman, Aminur; Haque, Md. Amirul; Hassan, Zahid; Wasay, Mohammad

    2016-01-01

    Background. Stroke is an important morbidity for low and middle income countries like Bangladesh. We established the first stroke registry in Bangladesh. Methods. Data was collected from stroke patients who were admitted in Department of Neurology of BIRDEM with first ever stroke, aged between 30 and 90 years. Patients with intracerebral hemorrhage, subarachnoid and subdural hemorrhage, and posttrauma features were excluded. Results. Data was gathered from 679 stroke patients. Mean age was 60.6 years. Almost 68% of patients were male. Small vessel strokes were the most common accounting for 45.4% of all the patients followed by large vessel getting affected in 32.5% of the cases. Only 16 (2.4%) died during treatment, and 436 (64.2%) patients had their mRS score of 3 to 5. Age greater than 70 years was associated with poor outcome on discharge [OR 1.79 (95% CI: 1.05 to 3.06)] adjusting for gender, duration of hospital stay, HDL, and pneumonia. Age, mRS, systolic blood pressure, urinary tract infection, pneumonia, and stroke severity explained the Barthel score. Conclusion. Mortality was low but most of patient had moderate to severe disability at discharge. Age, mRS, systolic blood pressure, urinary tract infection, pneumonia, and stroke severity influenced the Barthel score. PMID:27688924

  3. Ischemic Strokes: Observations from a Hospital Based Stroke Registry in Bangladesh.

    PubMed

    Bhowmik, Nirmalendu Bikash; Abbas, Aamir; Saifuddin, Mohammad; Islam, Md Rashedul; Habib, Rumana; Rahman, Aminur; Haque, Md Amirul; Hassan, Zahid; Wasay, Mohammad

    2016-01-01

    Background. Stroke is an important morbidity for low and middle income countries like Bangladesh. We established the first stroke registry in Bangladesh. Methods. Data was collected from stroke patients who were admitted in Department of Neurology of BIRDEM with first ever stroke, aged between 30 and 90 years. Patients with intracerebral hemorrhage, subarachnoid and subdural hemorrhage, and posttrauma features were excluded. Results. Data was gathered from 679 stroke patients. Mean age was 60.6 years. Almost 68% of patients were male. Small vessel strokes were the most common accounting for 45.4% of all the patients followed by large vessel getting affected in 32.5% of the cases. Only 16 (2.4%) died during treatment, and 436 (64.2%) patients had their mRS score of 3 to 5. Age greater than 70 years was associated with poor outcome on discharge [OR 1.79 (95% CI: 1.05 to 3.06)] adjusting for gender, duration of hospital stay, HDL, and pneumonia. Age, mRS, systolic blood pressure, urinary tract infection, pneumonia, and stroke severity explained the Barthel score. Conclusion. Mortality was low but most of patient had moderate to severe disability at discharge. Age, mRS, systolic blood pressure, urinary tract infection, pneumonia, and stroke severity influenced the Barthel score. PMID:27688924

  4. Ischemic Strokes: Observations from a Hospital Based Stroke Registry in Bangladesh

    PubMed Central

    Saifuddin, Mohammad; Islam, Md. Rashedul; Habib, Rumana; Rahman, Aminur; Haque, Md. Amirul; Hassan, Zahid; Wasay, Mohammad

    2016-01-01

    Background. Stroke is an important morbidity for low and middle income countries like Bangladesh. We established the first stroke registry in Bangladesh. Methods. Data was collected from stroke patients who were admitted in Department of Neurology of BIRDEM with first ever stroke, aged between 30 and 90 years. Patients with intracerebral hemorrhage, subarachnoid and subdural hemorrhage, and posttrauma features were excluded. Results. Data was gathered from 679 stroke patients. Mean age was 60.6 years. Almost 68% of patients were male. Small vessel strokes were the most common accounting for 45.4% of all the patients followed by large vessel getting affected in 32.5% of the cases. Only 16 (2.4%) died during treatment, and 436 (64.2%) patients had their mRS score of 3 to 5. Age greater than 70 years was associated with poor outcome on discharge [OR 1.79 (95% CI: 1.05 to 3.06)] adjusting for gender, duration of hospital stay, HDL, and pneumonia. Age, mRS, systolic blood pressure, urinary tract infection, pneumonia, and stroke severity explained the Barthel score. Conclusion. Mortality was low but most of patient had moderate to severe disability at discharge. Age, mRS, systolic blood pressure, urinary tract infection, pneumonia, and stroke severity influenced the Barthel score.

  5. Geometrical Effects on the Electromagnetic Radiation from Lightning Return Strokes

    NASA Technical Reports Server (NTRS)

    Willett, J. C.; Smith, D. A.; LeVine, D. M.; Zukor, Dorothy J. (Technical Monitor)

    2001-01-01

    The morphological difference between the electromagnetic radiation-field waveforms of "first" and "subsequent" return strokes in cloud-to-ground lightning flashes is well known and can be used to identify the formation of new channels to ground. This difference is generally believed due to the existence of branches on first-stroke channels, whereas subsequent strokes re-illuminate only the main channel of a previous stroke; but experimental evidence for this hypothesis is relatively weak. It has been argued for the influence of channel geometry on the fine structure of radiation from subsequent return strokes by comparing the field-change waveforms recorded at the same station from strokes within the same flash and between different flashes of both natural and triggered lightning. The present paper introduces new evidence for both of these hypotheses from a comparison of waveforms between sensors in different directions from the same stroke.

  6. Strokes in adults.

    PubMed

    Pearce, Lynne

    2016-06-15

    Essential facts There are two types of stroke - around 85% are ischaemic and 15% are haemorrhagic. According to the Stroke Association's State of the Nation report, published in January 2016, stroke occurs around 152,000 times a year in the UK. It is the fourth largest cause of death in the UK and one of the largest causes of disability. PMID:27305230

  7. Characteristics of a bipolar cloud-to-ground lightning flash containing a positive stroke followed by three negative strokes

    NASA Astrophysics Data System (ADS)

    Tian, Ye; Qie, Xiushu; Lu, Gaopeng; Jiang, Rubin; Wang, Zhichao; Zhang, Hongbo; Liu, Mingyuan; Sun, Zhuling; Feng, Guili

    2016-07-01

    Using time-correlated high-speed video images at 3200 frames per second, broadband electric field change data and low-frequency magnetic fields, a natural bipolar cloud-to-ground (CG) lightning flash with one first positive stroke followed by three subsequent negative strokes is analyzed. All of these four strokes transferred electric charge to the ground through the same lower channel with a time interval of 328 ms between the positive stroke and the first negative stroke. The flash onset was followed by several positive leaders that extended below the cloud base, one of which descended to culminate in a positive stroke with a continuing current. Another positive leader extended horizontally to a distant negative cloud region and induced several recoil leaders that intermittently retrograded along the leader channel. Eventually, three recoil leaders successively traversed along the path of positive stroke to produce respective negative strokes, resulting in the polarity reversal of charge transferred to the ground. The average two-dimensional (2-D) speed of the positive leader was 1.1 × 105 m/s, while for the 3 negative leaders was 6.7 × 106 m/s. The zero-crossing time and rise time of the radiation field waveform for the 3 negative strokes are smaller than the typical negative subsequent strokes, making them hard to be recognized as return strokes by the CG lightning location network.

  8. The European Stroke Organisation Guidelines: a standard operating procedure.

    PubMed

    Ntaios, George; Bornstein, Natan M; Caso, Valeria; Christensen, Hanne; De Keyser, Jacques; Diener, Hans-Christoph; Diez-Tejedor, Exuperio; Ferro, Jose M; Ford, Gary A; Grau, Armin; Keller, Emanuella; Leys, Didier; Russell, David; Toni, Danilo; Turc, Guillaume; Van der Worp, Bart; Wahlgren, Nils; Steiner, Thorsten

    2015-10-01

    In 2008, the recently founded European Stroke Organisation published its guidelines for the management of ischemic stroke and transient ischemic attack. This highly cited document was translated in several languages and was updated in 2009. Since then, the European Stroke Organisation has published guidelines for the management of intracranial aneurysms and subarachnoidal hemorrhage, for the establishment of stroke units and stroke centers, and recently for the management of intracerebral hemorrhage. In recent years, the methodology for the development of guidelines has evolved significantly. To keep pace with this progress and driven by the strong determination of the European Stroke Organisation to further promote stroke management, education, and research, the European Stroke Organisation decided to delineate a detailed standard operating procedure for its guidelines. There are two important cornerstones in this standard operating procedure: The first is the implementation of the Grading of Recommendations Assessment, Development, and Evaluation methodology for the development of its Guideline Documents. The second one is the decision of the European Stroke Organisation to move from the classical model of a single Guideline Document about a major topic (e.g. management of ischemic stroke) to focused modules (i.e. subdivisions of a major topic). This will enable the European Stroke Organisation to react faster when new developments in a specific stroke field occur and update its recommendations on the related module rather swiftly; with the previous approach of a single large Guideline Document, its entire revision had to be completed before an updated publication, delaying the production of up-to-date guidelines. After discussion within the European Stroke Organisation Guidelines Committee and significant input from European Stroke Organisation members as well as methodologists and analysts, this document presents the official standard operating procedure for

  9. Alterations in the corticotropin-releasing hormone (CRH) neurocircuitry: Insights into post stroke functional impairments.

    PubMed

    Barra de la Tremblaye, P; Plamondon, H

    2016-07-01

    Although it is well accepted that changes in the regulation of the hypothalamic-pituitary adrenal (HPA) axis may increase susceptibility to affective disorders in the general population, this link has been less examined in stroke patients. Yet, the bidirectional association between depression and cardiovascular disease is strong, and stress increases vulnerability to stroke. Corticotropin-releasing hormone (CRH) is the central stress hormone of the HPA axis pathway and acts by binding to CRH receptors (CRHR) 1 and 2, which are located in several stress-related brain regions. Evidence from clinical and animal studies suggests a role for CRH in the neurobiological basis of depression and ischemic brain injury. Given its importance in the regulation of the neuroendocrine, autonomic, and behavioral correlates of adaptation and maladaptation to stress, CRH is likely associated in the pathophysiology of post stroke emotional impairments. The goals of this review article are to examine the clinical and experimental data describing (1) that CRH regulates the molecular signaling brain circuit underlying anxiety- and depression-like behaviors, (2) the influence of CRH and other stress markers in the pathophysiology of post stroke emotional and cognitive impairments, and (3) context and site specific interactions of CRH and BDNF as a basis for the development of novel therapeutic targets. This review addresses how the production and release of the neuropeptide CRH within the various regions of the mesocorticolimbic system influences emotional and cognitive behaviors with a look into its role in psychiatric disorders post stroke. PMID:27455847

  10. Perturbation of Brain Oscillations after Ischemic Stroke: A Potential Biomarker for Post-Stroke Function and Therapy

    PubMed Central

    Rabiller, Gratianne; He, Ji-Wei; Nishijima, Yasuo; Wong, Aaron; Liu, Jialing

    2015-01-01

    Brain waves resonate from the generators of electrical current and propagate across brain regions with oscillation frequencies ranging from 0.05 to 500 Hz. The commonly observed oscillatory waves recorded by an electroencephalogram (EEG) in normal adult humans can be grouped into five main categories according to the frequency and amplitude, namely δ (1–4 Hz, 20–200 μV), θ (4–8 Hz, 10 μV), α (8–12 Hz, 20–200 μV), β (12–30 Hz, 5–10 μV), and γ (30–80 Hz, low amplitude). Emerging evidence from experimental and human studies suggests that groups of function and behavior seem to be specifically associated with the presence of each oscillation band, although the complex relationship between oscillation frequency and function, as well as the interaction between brain oscillations, are far from clear. Changes of brain oscillation patterns have long been implicated in the diseases of the central nervous system including ischemic stroke, in which the reduction of cerebral blood flow as well as the progression of tissue damage have direct spatiotemporal effects on the power of several oscillatory bands and their interactions. This review summarizes the current knowledge in behavior and function associated with each brain oscillation, and also in the specific changes in brain electrical activities that correspond to the molecular events and functional alterations observed after experimental and human stroke. We provide the basis of the generations of brain oscillations and potential cellular and molecular mechanisms underlying stroke-induced perturbation. We will also discuss the implications of using brain oscillation patterns as biomarkers for the prediction of stroke outcome and therapeutic efficacy. PMID:26516838

  11. White matter injury in ischemic stroke.

    PubMed

    Wang, Yuan; Liu, Gang; Hong, Dandan; Chen, Fenghua; Ji, Xunming; Cao, Guodong

    2016-06-01

    Stroke is one of the major causes of disability and mortality worldwide. It is well known that ischemic stroke can cause gray matter injury. However, stroke also elicits profound white matter injury, a risk factor for higher stroke incidence and poor neurological outcomes. The majority of damage caused by stroke is located in subcortical regions and, remarkably, white matter occupies nearly half of the average infarct volume. Indeed, white matter is exquisitely vulnerable to ischemia and is often injured more severely than gray matter. Clinical symptoms related to white matter injury include cognitive dysfunction, emotional disorders, sensorimotor impairments, as well as urinary incontinence and pain, all of which are closely associated with destruction and remodeling of white matter connectivity. White matter injury can be noninvasively detected by MRI, which provides a three-dimensional assessment of its morphology, metabolism, and function. There is an urgent need for novel white matter therapies, as currently available strategies are limited to preclinical animal studies. Optimal protection against ischemic stroke will need to encompass the fortification of both gray and white matter. In this review, we discuss white matter injury after ischemic stroke, focusing on clinical features and tools, such as imaging, manifestation, and potential treatments. We also briefly discuss the pathophysiology of WMI and future research directions. PMID:27090751

  12. White matter injury in ischemic stroke.

    PubMed

    Wang, Yuan; Liu, Gang; Hong, Dandan; Chen, Fenghua; Ji, Xunming; Cao, Guodong

    2016-06-01

    Stroke is one of the major causes of disability and mortality worldwide. It is well known that ischemic stroke can cause gray matter injury. However, stroke also elicits profound white matter injury, a risk factor for higher stroke incidence and poor neurological outcomes. The majority of damage caused by stroke is located in subcortical regions and, remarkably, white matter occupies nearly half of the average infarct volume. Indeed, white matter is exquisitely vulnerable to ischemia and is often injured more severely than gray matter. Clinical symptoms related to white matter injury include cognitive dysfunction, emotional disorders, sensorimotor impairments, as well as urinary incontinence and pain, all of which are closely associated with destruction and remodeling of white matter connectivity. White matter injury can be noninvasively detected by MRI, which provides a three-dimensional assessment of its morphology, metabolism, and function. There is an urgent need for novel white matter therapies, as currently available strategies are limited to preclinical animal studies. Optimal protection against ischemic stroke will need to encompass the fortification of both gray and white matter. In this review, we discuss white matter injury after ischemic stroke, focusing on clinical features and tools, such as imaging, manifestation, and potential treatments. We also briefly discuss the pathophysiology of WMI and future research directions.

  13. Perlecan domain V therapy for stroke: a beacon of hope?

    PubMed

    Bix, Gregory J

    2013-03-20

    The sad reality is that in the year 2012, people are still dying or suffering from the extreme morbidity of ischemic stroke. This tragedy is only compounded by the graveyard full of once promising new therapies. While it is indeed true that the overall mortality from stroke has declined in the United States, perhaps due to increased awareness of stroke symptoms by both the lay public and physicians, it is clear that better therapies are needed. In this regard, progress has been tremendously slowed by the simple fact that experimental models of stroke and the animals that they typically employ, rats and mice, do not adequately represent human stroke. Furthermore, the neuroprotective therapeutic approach, in which potential treatments are administered with the hope of preventing the spread of dying neurons that accompanies a stroke, typically fail for a number of reasons such as there is simply more brain matter to protect in a human than there is in a rodent! For this reason, there has been somewhat of a shift in stroke research away from neuroprotection and toward a neurorepair approach. This too may be problematic in that agents that might foster brain repair could be acutely deleterious or neurotoxic and vice versa, making the timing of treatment administration after stroke critical. Therefore, in our efforts to discover a new stroke therapy, we decided to focus on identifying brain repair elements that were (1) endogenously and actively generated in response to stroke in both human and experimental animal brains, (2) present acutely and chronically after ischemic stroke, suggesting that they could have a role in acute neuroprotection and chronic neurorepair, and (3) able to be administered peripherally and reach the site of stroke brain injury. In this review, I will discuss the evidence that suggests that perlecan domain V may be just that substance, a potential beacon of hope for stroke patients.

  14. [Post Stroke Dementia].

    PubMed

    Ihara, Masafumi

    2016-07-01

    Post-stroke dementia (PSD) is a clinical entity that encompasses all types of dementia following an index stroke. Current evidence suggests that 25-30% of ischemic stroke survivors develop immediate or delayed vascular cognitive impairment or vascular dementia. The type of stroke can be either ischemic, hemorrhagic or hypoperfusive. There are multiple risk factors for PSD including older age, family history, genetic variants, low educational status, vascular comorbidities, prior transient ischemic attack or recurrent stroke and depressive illness. Pre-stroke dementia refers to the occurrence of cognitive impairment before the index stroke, which may be caused by a vascular burden as well as insidious neurodegenerative changes. Neuroimaging determinants of dementia after stroke include silent brain infarcts, white matter changes, lacunar infarcts and medial temporal lobe atrophy. Published clinical trials have not been promising and there is little information on whether PSD can be prevented using pharmacological agents. Control of vascular disease risk and prevention of recurrent strokes are key to reducing the burden of cognitive decline and post-stroke dementia. Modern imaging and analysis techniques will help to elucidate the mechanism of PSD and establish better treatment. PMID:27395459

  15. Novel Stroke Therapeutics: Unraveling Stroke Pathophysiology and Its Impact on Clinical Treatments

    PubMed Central

    George, Paul M.; Steinberg, Gary K.

    2016-01-01

    Stroke remains a leading cause of death and disability in the world. Over the past few decades our understanding of the pathophysiology of stroke has increased, but greater insight is required to advance the field of stroke recovery. Clinical treatments have improved in the acute time window, but long-term therapeutics remain limited. Complex neural circuits damaged by ischemia make restoration of function after stroke difficult. New therapeutic approaches, including cell transplantation or stimulation, focus on reestablishing these circuits through multiple mechanisms to improve circuit plasticity and remodeling. Other research targets intact networks to compensate for damaged regions. This review highlights several important mechanisms of stroke injury and describes emerging therapies aimed at improving clinical outcomes. PMID:26182415

  16. Effects of alkylate fuel on exhaust emissions and secondary aerosol formation of a 2-stroke and a 4-stroke scooter

    NASA Astrophysics Data System (ADS)

    Zardini, Alessandro A.; Platt, Stephen M.; Clairotte, Michael; El Haddad, Imad; Temime-Roussel, Brice; Marchand, Nicolas; Ježek, Irena; Drinovec, Luka; Močnik, Griša; Slowik, Jay G.; Manfredi, Urbano; Prévôt, André S. H.; Baltensperger, Urs; Astorga, Covadonga

    2014-09-01

    Regulated and unregulated emissions from a 2-stroke and a 4-stroke scooter were characterized during a legislative driving cycle in a certified laboratory. Scooter exhaust was analyzed at the tailpipe, in a dilution tunnel, and partly collected in a mobile smog chamber for photochemical ageing. We present evidence that the photochemically aged exhaust from a 2-stroke and a 4-stroke scooter produces considerable amounts of secondary organic aerosol: from 1.5 to 22.0 mg/km, and from 5.5 to 6.6 mg/km, respectively. Tests were repeated after replacing the standard petrol and synthetic lube oil with an alkylate fuel (with low content of aromatic compounds) and ultra-clean lube oil (low ash forming potential). We observed emission reduction (with some exceptions) for several gaseous and particulate phase species, in particular for carbon monoxide (from 8% up to 38% and from 31% to 50%, for the 2-stroke and the 4-stroke scooters, respectively), particulate mass (from 32% up to 75% for the 2-stroke scooter), aromatic compounds (89% and 97% for the 2-stroke and the 4-stroke scooter, respectively), and secondary organic aerosol (from 87% to 100% and 99% for the 2-stroke and the 4-stroke scooters, respectively). We attribute the organic aerosol reduction to the low content of aromatics in the alkylate fuel.

  17. Literature and art therapy in post-stroke psychological disorders.

    PubMed

    Eum, Yeongcheol; Yim, Jongeun

    2015-01-01

    Stroke is one of the leading causes of morbidity and long-term disability worldwide, and post-stroke depression (PSD) is a common and serious psychiatric complication of stroke. PSD makes patients have more severe deficits in activities of daily living, a worse functional outcome, more severe cognitive deficits and increased mortality as compared to stroke patients without depression. Therefore, to reduce or prevent mental problems of stroke patients, psychological treatment should be recommended. Literature and art therapy are highly effective psychological treatment for stroke patients. Literature therapy divided into poetry and story therapy is an assistive tool that treats neurosis as well as emotional or behavioral disorders. Poetry can add impression to the lethargic life of a patient with PSD, thereby acting as a natural treatment. Story therapy can change the gloomy psychological state of patients into a bright and healthy story, and therefore can help stroke patients to overcome their emotional disabilities. Art therapy is one form of psychological therapy that can treat depression and anxiety in stroke patients. Stroke patients can express their internal conflicts, emotions, and psychological status through art works or processes and it would be a healing process of mental problems. Music therapy can relieve the suppressed emotions of patients and add vitality to the body, while giving them the energy to share their feelings with others. In conclusion, literature and art therapy can identify the emotional status of patients and serve as a useful auxiliary tool to help stroke patients in their rehabilitation process.

  18. Stroke rehabilitation: clinical picture, assessment, and therapeutic challenge.

    PubMed

    Richards, Carol L; Malouin, Francine; Nadeau, Sylvie

    2015-01-01

    This chapter reviews the evolution of stroke rehabilitation in the last 20 years. It begins by describing the different types of stroke that can occur in adults, their potential consequences on a person's capacity to function in daily life and statistics on the number of strokes and their burden on families and the economy. The assessment of stroke severity, recovery of function over time, and the impact of initial stroke severity and age on potential recovery are then addressed as well as the concept of rehabilitation to enhance recovery. Fueled by the synthesis of an ever-increasing research knowledge base and the creation of stroke rehabilitation recommendations for optimal delivery of rehabilitation services and of therapeutic interventions, stroke rehabilitation has changed dramatically. Examples of improvements in stroke rehabilitation in Canada are given with emphasis on the "best practices" inspired stroke rehabilitation continuum recently recommended for the Province of Quebec. The need for an improved community-based rehabilitation approach that includes regular follow-ups and community-based programs promoting reintegration is emphasized. The importance of knowledge translation strategies to promote the uptake of best-practice recommendations is illustrated by describing the activities of the Sensorimotor Rehabilitation Research Team. Over the past 3 years, the researchers of this team and clinicians in three rehabilitation centers, two in Montreal and one in Quebec City, have collaborated to adopt standardized assessment tools, create a common stroke registry, a best-practice recommended approach to interventions and the participation of clinicians in the research process.

  19. European Stroke Science Workshop

    PubMed Central

    Mattle, Heinrich P.; Brainin, Michael; Chamorro, Angel; Diener, Hans Christoph; Hacke, Werner; Leys, Didier; Norrving, Bo; Ward, Nick

    2012-01-01

    The European Stroke Organisation (ESO) held its first European Stroke Science Workshop in Garmisch-Partenkirchen, Germany (15-17 December 2011). Stroke experts based in Europe were invited to present and discuss their current research. The scope of the workshop was to review the most recent findings of selected topics in stroke, to exchange ideas, to stimulate new research and to enhance collaboration between European stroke research groups. Seven scientific sessions were held, each starting with a keynote lecture to review the state of the art of the given topic, followed by 4 or 5 short presentations by experts. They were asked to limit their presentations to 10 slides containing only recent information. The meeting was organized by the executive committee of the ESO (Heinrich Mattle, chairman, Michael Brainin, Angel Chamorro, Werner Hacke, Didier Leys) and supported by the European Stroke Conference (Michael Hennerici). In this article we summarize the main contents of this successful workshop. PMID:22836350

  20. Aspirin resistant patients with recent ischemic stroke.

    PubMed

    Castilla-Guerra, L; Navas-Alcántara, M S; Fernández-Moreno, M C

    2014-04-01

    Some patients with a recent ischemic stroke who are being treated with aspirin as an antiaggregant suffer a new ischemic stroke. These patients (15-25%) have been called unresponsive to aspirin or aspirin resistant. The aspirin-resistant patients have a four-time greater risk of suffering a stroke. Furthermore, these strokes are generally more severe, with increased infarct volume and greater risk of recurrence. There is currently no ideal laboratory test to detect the resistance to the antiaggregant effect of aspirin. The study of resistance to aspirin would only be indicated in selected cases. In these patients, one should first rule out any "pseudo-resistance" to aspirin (lack of compliance, concomitant treatments that interfere with the action of the aspirin). PMID:24211052

  1. Emerging Treatments for Motor Rehabilitation After Stroke

    PubMed Central

    Krishnan, Chandramouli; Khot, Sandeep P.

    2015-01-01

    Although numerous treatments are available to improve cerebral perfusion after acute stroke and prevent recurrent stroke, few rehabilitation treatments have been conclusively shown to improve neurologic recovery. The majority of stroke survivors with motor impairment do not recover to their functional baseline, and there remains a need for novel neurorehabilitation treatments to minimize long-term disability, maximize quality of life, and optimize psychosocial outcomes. In recent years, several novel therapies have emerged to restore motor function after stroke, and additional investigational treatments have also shown promise. Here, we familiarize the neurohospitalist with emerging treatments for poststroke motor rehabilitation. The rehabilitation treatments covered in this review will include selective serotonin reuptake inhibitor medications, constraint-induced movement therapy, noninvasive brain stimulation, mirror therapy, and motor imagery or mental practice. PMID:25829989

  2. Changes in brain functional network connectivity after stroke.

    PubMed

    Li, Wei; Li, Yapeng; Zhu, Wenzhen; Chen, Xi

    2014-01-01

    Studies have shown that functional network connection models can be used to study brain network changes in patients with schizophrenia. In this study, we inferred that these models could also be used to explore functional network connectivity changes in stroke patients. We used independent component analysis to find the motor areas of stroke patients, which is a novel way to determine these areas. In this study, we collected functional magnetic resonance imaging datasets from healthy controls and right-handed stroke patients following their first ever stroke. Using independent component analysis, six spatially independent components highly correlated to the experimental paradigm were extracted. Then, the functional network connectivity of both patients and controls was established to observe the differences between them. The results showed that there were 11 connections in the model in the stroke patients, while there were only four connections in the healthy controls. Further analysis found that some damaged connections may be compensated for by new indirect connections or circuits produced after stroke. These connections may have a direct correlation with the degree of stroke rehabilitation. Our findings suggest that functional network connectivity in stroke patients is more complex than that in hea-lthy controls, and that there is a compensation loop in the functional network following stroke. This implies that functional network reorganization plays a very important role in the process of rehabilitation after stroke. PMID:25206743

  3. An experimental study of several wind tunnel wall configurations using two V/STOL model configurations. [low speed wind tunnels

    NASA Technical Reports Server (NTRS)

    Binion, T. W., Jr.

    1975-01-01

    Experiments were conducted in the low speed wind tunnel using two V/STOL models, a jet-flap and a jet-in-fuselage configuration, to search for a wind tunnel wall configuration to minimize wall interference on V/STOL models. Data were also obtained on the jet-flap model with a uniform slotted wall configuration to provide comparisons between theoretical and experimental wall interference. A test section configuration was found which provided some data in reasonable agreement with interference-free results over a wide range of momentum coefficients.

  4. Neurorestoration after stroke.

    PubMed

    Azad, Tej D; Veeravagu, Anand; Steinberg, Gary K

    2016-05-01

    Recent advancements in stem cell biology and neuromodulation have ushered in a battery of new neurorestorative therapies for ischemic stroke. While the understanding of stroke pathophysiology has matured, the ability to restore patients' quality of life remains inadequate. New therapeutic approaches, including cell transplantation and neurostimulation, focus on reestablishing the circuits disrupted by ischemia through multidimensional mechanisms to improve neuroplasticity and remodeling. The authors provide a broad overview of stroke pathophysiology and existing therapies to highlight the scientific and clinical implications of neurorestorative therapies for stroke.

  5. Neurological emergencies: acute stroke

    PubMed Central

    Davenport, R.; Dennis, M.

    2000-01-01

    Stroke causes a vast amount of death and disability throughout the world, yet for many healthcare professionals it remains an area of therapeutic nihilism, and thus uninteresting. This negative perception is shared by the general public, who often have a poor understanding of the early symptoms and significance of a stroke. Yet within the past few years there have been many important developments in the approach to caring for stroke patients, for both the acute management and secondary prevention. After the completion of numerous clinical trials, there is now robust evidence to either support or discredit various interventions. Even more exciting is the prospect of yet more data becoming available in the near future, testing a whole array of treatments, as clinical interest in stroke expands exponentially. In this review an evidence based approach to the management of acute stroke within the first few days is presented, including ischaemic and haemorrhagic events, but not subarachnoid haemorrhage. It is explained why stroke is regarded as a medical emergency, and the importance of a rational, methodic approach to the initial assessment, which is the key to accurate diagnosis and subsequent management, is emphasised. The potential early problems associated with stroke are identified and specific interventions for different stroke types are discussed. The review ends with a brief discussion of the implications that the evolving treatments have for the organisation of modern stroke services.

 PMID:10675208

  6. Stroke in Latin America.

    PubMed

    Camargo, Erica C S; Bacheschi, Luiz A; Massaro, Ayrton R

    2005-05-01

    Stroke is one of the leading causes of mortality in Latin America, with variable incidence and prevalence throughout the continent reflecting regional socioeconomic differences. In Latin America, uncontrolled hypertension is one of the major causes of stroke, but other modifiable risk factors also play a role, such as heavy alcohol consumption and smoking. Intracerebral hemorrhage and lacunar stroke are more frequent in Latin America than in North America and Europe. There are multiple causes of stroke that are endemic to Latin America, including neurocysticercosis, Chagas' disease, sickle cell anemia, malaria, hemorrhagic fever, and snake bites.

  7. Neurorestoration after stroke

    PubMed Central

    Azad, Tej D.; Veeravagu, Anand; Steinberg, Gary K.

    2016-01-01

    Recent advancements in stem cell biology and neuromodulation have ushered in a battery of new neurorestorative therapies for ischemic stroke. While the understanding of stroke pathophysiology has matured, the ability to restore patients’ quality of life remains inadequate. New therapeutic approaches, including cell transplantation and neurostimulation, focus on reestablishing the circuits disrupted by ischemia through multidimensional mechanisms to improve neuroplasticity and remodeling. The authors provide a broad overview of stroke pathophysiology and existing therapies to highlight the scientifc and clinical implications of neurorestorative therapies for stroke. PMID:27132523

  8. Stroke Drills for Swimming Instructors.

    ERIC Educational Resources Information Center

    Cahill, Peter J.

    1982-01-01

    Stroke drills to be used by swimming instructors to teach four competitive swim strokes are described. The drills include: one arm swims; (2) alternative kicks; (3) fist swims; and (4) catch-up strokes. (JN)

  9. Animal Stroke Model: Ischemia-Reperfusion and Intracerebral Hemorrhage.

    PubMed

    Ren, Changhong; Sy, Christopher; Gao, Jinhuan; Ding, Yuchuan; Ji, Xunming

    2016-01-01

    Stroke is a major health issue worldwide-one with serious financial and public health implications. As a result, ongoing clinical research on novel and improved stroke therapies is not only pertinent but also paramount. Due to the complexity of a stroke-like event and its many sequelae, devising usable methods and experimental models are necessary to study and better understand the pathophysiological processes that ensue. As it stands, animal models that simulate stroke-like events have proven to be the most logical and effective options in regards to experimental studies. A number of animal stroke models exist and have been demonstrated in previous studies on ischemic as well as hemorrhagic stroke. Considering the efficiency and reproducibility of animal models, here, we introduce an ischemic stroke model induced by middle cerebral artery occlusion (MCAO) and an intracerebral hemorrhagic stroke model induced by collagenase injection. The models outlined here have been proven to demonstrate the clinical relevance desired for use in continued research on stroke pathophysiology and the study of future therapeutic options. PMID:27604729

  10. Primary blast causes mild, moderate, severe and lethal TBI with increasing blast overpressures: Experimental rat injury model

    PubMed Central

    Mishra, Vikas; Skotak, Maciej; Schuetz, Heather; Heller, Abi; Haorah, James; Chandra, Namas

    2016-01-01

    Injury severity in blast induced Traumatic Brain Injury (bTBI) increases with blast overpressure (BOP) and impulse in dose-dependent manner. Pure primary blast waves were simulated in compressed gas shock-tubes in discrete increments. Present work demonstrates 24 hour survival of rats in 0–450 kPa (0–800 Pa∙s impulse) range at 10 discrete levels (60, 100, 130, 160, 190, 230, 250, 290, 350 and 420 kPa) and determines the mortality rate as a non-linear function of BOP. Using logistic regression model, predicted mortality rate (PMR) function was calculated, and used to establish TBI severities. We determined a BOP of 145 kPa as upper mild TBI threshold (5% PMR). Also we determined 146–220 kPa and 221–290 kPa levels as moderate and severe TBI based on 35%, and 70% PMR, respectively, while BOP above 290 kPa is lethal. Since there are no standards for animal bTBI injury severity, these thresholds need further refinements using histopathology, immunohistochemistry and behavior. Further, we specifically investigated mild TBI range (0–145 kPa) using physiological (heart rate), pathological (lung injury), immuno-histochemical (oxidative/nitrosative and blood-brain barrier markers) as well as blood borne biomarkers. With these additional data, we conclude that mild bTBI occurs in rats when the BOP is in the range of 85–145 kPa. PMID:27270403

  11. Primary blast causes mild, moderate, severe and lethal TBI with increasing blast overpressures: Experimental rat injury model

    NASA Astrophysics Data System (ADS)

    Mishra, Vikas; Skotak, Maciej; Schuetz, Heather; Heller, Abi; Haorah, James; Chandra, Namas

    2016-06-01

    Injury severity in blast induced Traumatic Brain Injury (bTBI) increases with blast overpressure (BOP) and impulse in dose-dependent manner. Pure primary blast waves were simulated in compressed gas shock-tubes in discrete increments. Present work demonstrates 24 hour survival of rats in 0–450 kPa (0–800 Pa•s impulse) range at 10 discrete levels (60, 100, 130, 160, 190, 230, 250, 290, 350 and 420 kPa) and determines the mortality rate as a non-linear function of BOP. Using logistic regression model, predicted mortality rate (PMR) function was calculated, and used to establish TBI severities. We determined a BOP of 145 kPa as upper mild TBI threshold (5% PMR). Also we determined 146–220 kPa and 221–290 kPa levels as moderate and severe TBI based on 35%, and 70% PMR, respectively, while BOP above 290 kPa is lethal. Since there are no standards for animal bTBI injury severity, these thresholds need further refinements using histopathology, immunohistochemistry and behavior. Further, we specifically investigated mild TBI range (0–145 kPa) using physiological (heart rate), pathological (lung injury), immuno-histochemical (oxidative/nitrosative and blood-brain barrier markers) as well as blood borne biomarkers. With these additional data, we conclude that mild bTBI occurs in rats when the BOP is in the range of 85–145 kPa.

  12. Primary blast causes mild, moderate, severe and lethal TBI with increasing blast overpressures: Experimental rat injury model.

    PubMed

    Mishra, Vikas; Skotak, Maciej; Schuetz, Heather; Heller, Abi; Haorah, James; Chandra, Namas

    2016-01-01

    Injury severity in blast induced Traumatic Brain Injury (bTBI) increases with blast overpressure (BOP) and impulse in dose-dependent manner. Pure primary blast waves were simulated in compressed gas shock-tubes in discrete increments. Present work demonstrates 24 hour survival of rats in 0-450 kPa (0-800 Pa∙s impulse) range at 10 discrete levels (60, 100, 130, 160, 190, 230, 250, 290, 350 and 420 kPa) and determines the mortality rate as a non-linear function of BOP. Using logistic regression model, predicted mortality rate (PMR) function was calculated, and used to establish TBI severities. We determined a BOP of 145 kPa as upper mild TBI threshold (5% PMR). Also we determined 146-220 kPa and 221-290 kPa levels as moderate and severe TBI based on 35%, and 70% PMR, respectively, while BOP above 290 kPa is lethal. Since there are no standards for animal bTBI injury severity, these thresholds need further refinements using histopathology, immunohistochemistry and behavior. Further, we specifically investigated mild TBI range (0-145 kPa) using physiological (heart rate), pathological (lung injury), immuno-histochemical (oxidative/nitrosative and blood-brain barrier markers) as well as blood borne biomarkers. With these additional data, we conclude that mild bTBI occurs in rats when the BOP is in the range of 85-145 kPa. PMID:27270403

  13. Stroke is an emergency.

    PubMed

    Futrell, N; Millikan, C H

    1996-04-01

    Stroke is an emergency. Ischemic stroke is similar to myocardial infarction in that the pathogenesis is loss of blood supply to the tissue, which can result in irreversible damage if blood flow is not restored quickly. Public education is needed to emphasize the warning signs of stroke. Patients should seek medical help immediately, using emergency transport systems. Therapy geared toward minimizing the damage from an acute stroke should be started without delay in the emergency room. This includes measures to protect brain tissue, support perfusion pressure, and minimize cerebral edema. Strategies for improving recovery should also begin immediately. All major medical centers need stroke teams and stroke units. Stroke prevention should be given high priority as a public health strategy. Risk factor management should be part of general health care and should begin in childhood, with emphasis on nutrition, exercise, weight control, and avoidance of tobacco. Health screening and early treatment of hypertension and hypercholesterolemia has decreased the incidence of stroke and heart disease, but these efforts need to be expanded to reach all segments of the population. Basic research has opened the door to new therapies aimed at re-establishing blood flow and limiting tissue damage. Clinical trials have already led to changes in stroke prevention, including studies of carotid endarterectomy and ticlopidine and warfarin therapy (for patients with atrial fibrillation). Trials in progress are testing the usefulness of ancrod, neuroprotective agents, antioxidant agents, anti-inflammatory agents, low-molecular-weight heparin, thrombolytic drugs, and angioplasty. Any delay starting therapy after an acute stroke will result in progressive, irreversible loss of brain tissue. Clinicians should remember that for a stroke patient, time is brain tissue.

  14. Picturing the Size and Site of Stroke With an Expanded National Institutes of Health Stroke Scale

    PubMed Central

    Agis, Daniel; Goggins, Maria B.; Oishi, Kumiko; Oishi, Kenichi; Davis, Cameron; Wright, Amy; Kim, Eun Hye; Sebastian, Rajani; Tippett, Donna C.; Faria, Andreia

    2016-01-01

    Background and Purpose— The National Institutes of Health Stroke Scale (NIHSS) includes minimal assessment of cognitive function, particularly in right hemisphere (RH) stroke. Descriptions of the Cookie Theft picture from the NIHSS allow analyses that (1) correlate with aphasia severity and (2) identify communication deficits in RH stroke. We hypothesized that analysis of the picture description contributes valuable information about volume and location of acute stroke. Methods— We evaluated 67 patients with acute ischemic stroke (34 left hemisphere [LH]; 33 RH) with the NIHSS, analysis of the Cookie Theft picture, and magnetic resonance imaging, compared with 35 sex- and age-matched controls. We evaluated descriptions for total content units (CU), syllables, ratio of left:right CU, CU/minute, and percent interpretive CU, based on previous studies. Lesion volume and percent damage to regions of interest were measured on diffusion-weighted imaging. Multivariable linear regression identified variables associated with infarct volume, independently of NIHSS score, age and sex. Results— Patients with RH and LH stroke differed from controls, but not from each other, on CU, syllables/CU, and CU/minute. Left:right CU was lower in RH compared with LH stroke. CU, syllables/CU, and NIHSS each correlated with lesion volume in LH and RH stroke. Lesion volume was best accounted by a model that included CU, syllables/CU, NIHSS, left:right CU, percent interpretive CU, and age, in LH and RH stroke. Each discourse variable and NIHSS score were associated with percent damage to different regions of interest, independently of lesion volume and age. Conclusions— Brief picture description analysis complements NIHSS scores in predicting stroke volume and location. PMID:27217502

  15. Adaptation to stroke using a model of successful aging.

    PubMed

    Donnellan, C; Hevey, D; Hickey, A; O'Neill, D

    2012-01-01

    The process of adaptation to the physical and psychosocial consequences after stroke is a major challenge for many individuals affected. The aim of this study was to examine if stroke patients within 1 month of admission (n = 153) and followed up at 1 year (n = 107) engage in selection, optimization, and compensation (SOC) adaptive strategies and the relationship of these strategies with functional ability, health-related quality of life (HRQOL) and depression 1 year later. Adaptive strategies were measured using a 15-item SOC questionnaire. Internal and external resources were assessed including recovery locus of control, stroke severity, and socio-demographics. Outcome measures were the Stroke Specific Quality of Life Questionnaire (SS-QoL), the Nottingham Extended Activities of Daily Living Scale and the Depression Subscale of the Hospital Anxiety and Depression Scale. Findings indicated that stroke patients engaged in the use of SOC strategies but the use of these strategies were not predictive of HRQOL, functional ability or depression 1 year after stroke. The use of SOC strategies were not age specific and were consistent over time, with the exception of the compensation subscale. Results indicate that SOC strategies may potentially be used in response to loss regulation after stroke and that an individual's initial HRQOL functional ability, levels of depression and socio-economic status that are important factors in determining outcome 1 year after stroke. A stroke-specific measure of SOC may be warranted in order to detect significant differences in determining outcomes for a stroke population.

  16. Experimental results from containment piping bellows subjected to severe accident conditions: Results from bellows tested in corroded conditions. Volume 2

    SciTech Connect

    Lambert, L.D.; Parks, M.B.

    1995-10-01

    Bellows are an integral part of the containment pressure boundary in nuclear power plants. They are used at piping penetrations to allow relative movement between piping and the containment wall, while minimizing the load imposed on the piping and wall. Piping bellows are primarily used in steel containments; however, they have received limited use in some concrete (reinforced and prestressed) containments. In a severe accident they may be subjected to pressure and temperature conditions that exceed the design values, along with a combination of axial and lateral deflections. A test program to determine the leak-tight capacity of containment penetration bellows is being conducted at Sandia National Laboratories under the sponsorship of the US Nuclear Regulatory Commission. Several different bellows geometries, representative of actual containment bellows, have been subjected to extreme deflections along with pressure and temperature loads. The bellows geometries and loading conditions are described along with the testing apparatus and procedures. A total of nineteen bellows have been tested. Thirteen bellows were tested in ``like-new`` condition (results reported in Volume 1), and six were tested in a corroded condition. The tests showed that bellows in ``like-new`` condition are capable of withstanding relatively large deformations, up to, or near, the point of full compression or elongation, before developing leakage, while those in a corroded condition did not perform as well, depending on the amount of corrosion. The corroded bellows test program and results are presented in this report.

  17. A garlic derivative, ajoene, inhibits platelet deposition on severely damaged vessel wall in an in vivo porcine experimental model.

    PubMed

    Apitz-Castro, R; Badimon, J J; Badimon, L

    1994-08-01

    Ajoene, (E,Z)-4,5,9-trithiadodeca-1,6,11-triene 9-oxide, is a potent antiplatelet compound isolated from alcoholic extracts of garlic. In vitro, ajoene reversibly inhibits platelet aggregation as well as the release reaction induced by all known agonists. We used a well characterized perfusion chamber to study the in vivo effects of ajoene on platelet deposition onto a highly thrombogenic, severely damaged arterial wall, obtained by stripping off the intimal layer and exposing tunica media. Platelet-vessel wall interaction and the effect of ajoene was studied under flow conditions of high and low local shear rate that mimics laminar blood flow in small and medium size arteries (1690 sec-1 and 212 sec-1). Our results indicate that administration of ajoene to heparinized animals, significantly prevents thrombus formation at local low blood shear rate. Ajoene does not inhibit binding of vWF to GPIb, therefore, it does not affect platelet adhesion. In fact, although ajoene impairs fibrinogen and vWF (less efficient) binding to GPlIb/IIIa, it does not totally inhibits platelet deposition to the substrates at any of the shear rates used in this study. Our present results, under in vivo flow conditions and in the presence of physiological calcium levels, suggest that ajoene may be potentially useful for the acute prevention of thrombus formation induced by severe vascular damage, mainly in arterial sites with local low shear rates.

  18. Vulnerability to Stroke: Implications of Perinatal Programming of the Hypothalamic-Pituitary-Adrenal Axis

    PubMed Central

    Craft, Tara K. S.; DeVries, A. Courtney

    2009-01-01

    Chronic stress is capable of exacerbating each major, modifiable, endogenous risk factor for cerebrovascular and cardiovascular disease. Indeed, exposure to stress can increase both the incidence and severity of stroke, presumably through activation of the hypothalamic-pituitary-adrenal (HPA) axis. Now that characterization of the mechanisms underlying epigenetic programming of the HPA axis is well underway, there has been renewed interest in examining the role of early environment on the evolution of health conditions across the entire lifespan. Indeed, neonatal manipulations in rodents that reduce stress responsivity, and subsequent life-time exposure to glucocorticoids, are associated with a reduction in the development of neuroendocrine, neuroanatomical, and cognitive dysfunctions that typically progress with age. Although improved day to day regulation of the HPA axis also may be accompanied by a decrease in stroke risk, evidence from rodent studies suggest that an associated cost could be increased susceptibility to inflammation and neuronal death in the event that a stroke does occur and the individual is exposed to persistently elevated corticosteroids. Given its importance in regulation of health and disease states, any long-term modulation of the HPA axis is likely to be associated with both benefits and potential risks. The goals of this review article are to examine (1) the clinical and experimental data suggesting that neonatal experiences can shape HPA axis regulation, (2) the influence of stress and the HPA axis on stroke incidence and severity, and (3) the potential for neonatal programming of the HPA axis to impact adult cerebrovascular health. PMID:20057937

  19. White matter injury and microglia/macrophage polarization are strongly linked with age-related long-term deficits in neurological function after stroke.

    PubMed

    Suenaga, Jun; Hu, Xiaoming; Pu, Hongjian; Shi, Yejie; Hassan, Sulaiman Habib; Xu, Mingyue; Leak, Rehana K; Stetler, R Anne; Gao, Yanqin; Chen, Jun

    2015-10-01

    Most of the successes in experimental models of stroke have not translated well to the clinic. One potential reason for this failure is that stroke mainly afflicts the elderly and the majority of experimental stroke studies rely on data gathered from young adult animals. Therefore, in the present study we established a reliable, reproducible model of stroke with low mortality in aged (18month) male mice and contrasted their pathophysiological changes with those in young (2month) animals. To this end, mice were subjected to permanent tandem occlusion of the left distal middle cerebral artery (dMCAO) with ipsilateral common carotid artery occlusion (CCAO). Cerebral blood flow (CBF) was evaluated repeatedly during and after stroke. Reduction of CBF was more dramatic and sustained in aged mice. Aged mice exhibited more severe long-term sensorimotor deficits, as manifested by deterioration of performance in the Rotarod and hanging wire tests up to 35d after stroke. Aged mice also exhibited significantly worse long-term cognitive deficits after stroke, as measured by the Morris water maze test. Consistent with these behavioral observations, brain infarct size and neuronal tissue loss after dMCAO were significantly larger in aged mice at 2d and 14d, respectively. The young versus aged difference in neuronal tissue loss, however, did not persist until 35d after dMCAO. In contrast to the transient difference in neuronal tissue loss, we found significant and long lasting deterioration of white matter in aged animals, as revealed by the loss of myelin basic protein (MBP) staining in the striatum at 35d after dMCAO. We further examined the expression of M1 (CD16/CD32) and M2 (CD206) markers in Iba-1(+) microglia by double immunofluorescent staining. In both young and aged mice, the expression of M2 markers peaked around 7d after stroke whereas the expression of M1 markers peaked around 14d after stroke, suggesting a progressive M2-to-M1 phenotype shift in both groups. However

  20. White matter injury and microglia/macrophage polarization are strongly linked with age-related long-term deficits in neurological function after stroke

    PubMed Central

    Suenaga, Jun; Hu, Xiaoming; Pu, Hongjian; Shi, Yejie; Hassan, Sulaiman Habib; Xu, Mingyue; Leak, Rehana K.; Stetler, R. Anne; Gao, Yanqin; Chen, Jun

    2015-01-01

    Most of the successes in experimental models of stroke have not translated well to the clinic. One potential reason for this failure is that stroke mainly afflicts the elderly and the majority of experimental stroke studies rely on data gathered from young adult animals. Therefore, in the present study we established a reliable, reproducible model of stroke with low mortality in aged (18 month) male mice and contrasted their pathophysiological changes with those in young (2 month) animals. To this end, mice were subjected to permanent tandem occlusion of the left distal middle cerebral artery (dMCAO) with ipsilateral common carotid artery occlusion (CCAO). Cerebral blood flow (CBF) was evaluated repeatedly during and after stroke. Reduction of CBF was more dramatic and sustained in aged mice. Aged mice exhibited more severe long-term sensorimotor deficits, as manifested by deterioration of performance in the Rotarod and hanging wire tests up to 35d after stroke. Aged mice also exhibited significantly worse long-term cognitive deficits after stroke, as measured by the Morris water maze test. Consistent with these behavioral observations, brain infarct size and neuronal tissue loss after dMCAO were significantly larger in aged mice at 2d and 14d, respectively. The young versus aged difference in neuronal tissue loss, however, did not persist until 35d after dMCAO. In contrast to the transient difference in neuronal tissue loss, we found significant and long lasting deterioration of white matter in aged animals, as revealed by the loss of myelin basic protein (MBP) staining in the striatum at 35d after dMCAO. We further examined the expression of M1 (CD16/CD32) and M2 (CD206) markers in Iba-1+ microglia by double immunofluorescent staining. In both young and aged mice, the expression of M2 markers peaked around 7d after stroke whereas the expression of M1 markers peaked around 14d after stroke, suggesting a progressive M2-to-M1 phenotype shift in both groups. However

  1. [Stroke management in Germany].

    PubMed

    Fritze, J

    2001-12-01

    Stroke is a leading cause of morbidity and mortality (rank 3) and thus a mass disease. Therefore, immediate access for everybody to stroke treatment services is indispensible. Therapeutic efficacy has been shown for lysis therapy and early rehabilitation in stroke units, respectively. The British-Scandinavian stroke unit concept focusses on immediately starting rehabilitation over 4-6 weeks by a specifically trained and motivated team. Since 1995, so-called stroke units are established in Germany adhering to a specific concept of the German Society for Neurology (DGN). Although referring to the British-Scandinavian concept in terms of efficacy the German concept differs fundamentally by focussing on monitoring as well as lysis therapy and neuroprotection in a short (3-5 days) stay. This is an intensive care unit approach for which scientific evidence is lacking. More essential are reasonable doubts that this concept can ever expand sufficiently to ensure comprehensive care. At least presently, stroke care is provided unevenly, thus contravening legislation (section 70 Social Security Act Vol. V). Acknowledging the restrictions the DGN adapted its concept, now advocating a two-step model comprising intensive care stroke units plus rehabilitative stroke units. PMID:11761782

  2. Relational Processing Following Stroke

    ERIC Educational Resources Information Center

    Andrews, Glenda; Halford, Graeme S.; Shum, David; Maujean, Annick; Chappell, Mark; Birney, Damian

    2013-01-01

    The research examined relational processing following stroke. Stroke patients (14 with frontal, 30 with non-frontal lesions) and 41 matched controls completed four relational processing tasks: sentence comprehension, Latin square matrix completion, modified Dimensional Change Card Sorting, and n-back. Each task included items at two or three…

  3. Age Alterations in Extent and Severity of Experimental Intranasal Infection with Chlamydophila pneumoniae in BALB/c Mice

    PubMed Central

    Little, C. Scott; Bowe, Andrew; Lin, Richard; Litsky, Jason; Fogel, Robert M.; Balin, Brian J.; Fresa-Dillon, Kerin L.

    2005-01-01

    The intracellular bacterium Chlamydophila (“Chlamydia”) pneumoniae is a pathogen for several respiratory diseases and may be a factor in the pathogenesis of chronic diseases of aging including atherosclerosis and Alzheimer's disease. We assessed whether aging is coupled with increased burden of infection in BALB/c mice after intranasal infection by C. pneumoniae. Six- and twenty-month-old BALB/c mice were infected intranasally with 5 × 104 inclusion forming units (IFU) or 5 × 105 IFU of C. pneumoniae. Lung, brain, and heart tissue were analyzed for infectious C. pneumoniae and for Chlamydophila antigen by immunohistochemistry. At both doses, aging was associated with a decreased proportion of animals that cleared infection from the lung and greater burden of infectious organism within the lung. We observed dose-dependent spread to the heart/ascending aorta in animals infected with C. pneumoniae. In mice given 5 × 104 IFU, spread to the heart by day 14 was only observed in old mice. By day 28, all animals inoculated with 5 × 104 IFU showed evidence of spread to the heart, although higher C. pneumoniae titers were observed in the hearts from old mice. In mice inoculated with 5 × 105 IFU, spread of C. pneumoniae to the heart was evident by day 14, with no discernible age effect. C. pneumoniae was also recovered from the central nervous system (brain and olfactory bulb) of all mice by day 28 postinfection, with higher C. pneumoniae titers in old animals than in young animals. Our results suggest that infection with C. pneumoniae may be more severe in old animals. PMID:15731073

  4. Trypanosomiasis, cardiomyopathy and the risk of ischemic stroke.

    PubMed

    Carod-Artal, Francisco Javier

    2010-05-01

    American (Chagas disease) and African (sleeping sickness) trypanosomiasis are neglected tropical diseases and are a heavy burden in Latin America and Africa, respectively. Chagas disease is an independent risk factor for stroke. Apical aneurysm, heart failure and cardiac arrhythmias are associated with ischemic stroke in chagasic cardiomyopathy. Not all chagasic patients who suffer an ischemic stroke have a severe cardiomyopathy, and stroke may be the first manifestation of Chagas disease. Cardioembolism affecting the middle cerebral artery is the most common stroke subtype. Risk of recurrence is high and careful evaluation of recurrence risk should be addressed. Repolarization changes, low voltage and prolonged QT interval are common electrocardiography alterations in human African trypanosomiasis, and can be found in more than 70% of patients. Epidemiological studies are needed to asses the risk of stroke in African trypanosomiasis perimyocarditis.

  5. The Role of Omega-3 Polyunsaturated Fatty Acids in Stroke

    PubMed Central

    Bu, Jiyuan; Dou, Yang; Tian, Xiaodi; Wang, Zhong

    2016-01-01

    Stroke is the third commonest cause of death following cardiovascular diseases and cancer. In particular, in recent years, the morbidity and mortality of stroke keep remarkable growing. However, stroke still captures people attention far less than cardiovascular diseases and cancer. Past studies have shown that oxidative stress and inflammation play crucial roles in the progress of cerebral injury induced by stroke. Evidence is accumulating that the dietary supplementation of fish oil exhibits beneficial effects on several diseases, such as cardiovascular diseases, metabolic diseases, and cancer. Omega-3 polyunsaturated fatty acids (n-3 PUFAs), the major component of fish oil, have been found against oxidative stress and inflammation in cardiovascular diseases. And the potential of n-3 PUFAs in stroke treatment is attracting more and more attention. In this review, we will review the effects of n-3 PUFAs on stroke and mainly focus on the antioxidant and anti-inflammatory effects of n-3 PUFAs. PMID:27433289

  6. Cocaine use and stroke

    PubMed Central

    Treadwell, Sean D; Robinson, Tom G

    2007-01-01

    Stroke is the third most common cause of death in developed countries. In England and Wales, 1000 people under the age of 30 have a stroke each year. Cocaine is the most commonly used class A drug, and the first report of cocaine‐induced stroke was in 1977. Since the development of alkaloidal “crack” cocaine in the 1980s, there has been a significant rise in the number of case reports describing both ischaemic and haemorrhagic stroke associated with cocaine use. Cocaine is a potent central nervous system stimulant, and acts by binding to specific receptors at pre‐synaptic sites preventing the reuptake of neurotransmitters. The exact mechanism of cocaine‐induced stroke remains unclear and there are likely to be a number of factors involved including vasospasm, cerebral vasculitis, enhanced platelet aggregation, cardioembolism, and hypertensive surges associated with altered cerebral autoregulation. The evidence surrounding each of these factors will be considered here. PMID:17551070

  7. Growth factors and stem cells as treatments for stroke recovery.

    PubMed

    Cairns, Kevin; Finklestein, Seth P

    2003-02-01

    Both polypeptide growth factors and stem cell populations from bone marrow and umbilical cord blood hold promise as treatments to enhance neurologic recovery after stroke. Growth factors may exert their effects through stimulation of neural sprouting and enhancement of endogenous progenitor cell proliferation, migration, and differentiation in brain. Exogenous stem cells may exert their effects by acting as miniature "factories" for trophic substances in the poststroke brain. The combination of growth factors and stem cells may be more effective than either treatment alone. Stroke recovery represents a new and relatively untested target for stroke therapeutics. Whereas acute stroke treatments focus on agents that dissolve blot clots (thrombolytics) and antagonize cell death (neuroprotective agents), stroke recovery treatments are likely to enhance structural and functional reorganization (plasticity) of the damaged brain. Successful clinical trials of stroke recovery-promoting agents are likely to be quite different from trials testing acute stroke therapies. In particular, the time window of effective treatment to enhance stroke recovery is likely to be far longer than that for acute stroke treatments, perhaps days or weeks rather than minutes or hours after stroke. This longer time window means that time is available for careful screening and testing of potential subjects for stroke recovery trials, both in terms of size and location of cerebral infarcts and in type and severity of neurologic deficits. Detailed baseline information can be obtained for each patient against which eventual clinical outcome can be compared. Finally, separate and detailed outcome measures can be obtained in both the sensorimotor and cognitive neurologic spheres, because it is possible that these two kinds of function may recover differently or be differentially responsive to recovery-promoting treatments. Stroke recovery represents an important and underexplored opportunity for the

  8. Efficacy of several vaccination programmes in commercial layer and broiler breeder hens against experimental challenge with Salmonella enterica serovar Enteritidis.

    PubMed

    Penha Filho, Rafael Antonio Casarin; de Paiva, Jacqueline Boldrin; Arguello, Yuli Melisa Sierra; da Silva, Mariana Dias; Gardin, Yannick; Resende, Fernando; Berchieri Junior, Angelo Berchieri; Sesti, Luiz

    2009-10-01

    Two experiments were performed to evaluate the protective effect of various vaccination combinations given at 5 and 9 weeks of age against experimental challenge with Salmonella enterica serovar Enteritidis (SE) phage type 4 at 12 weeks of age. In Experiment 1, groups of commercial layers were vaccinated by one of the following programmes: Group 1, two doses of a SE bacterin (Layermune SE); Group 2, one dose of a live Salmonella enterica serovar Gallinarum vaccine (Cevac SG9R) followed by one dose of the SE bacterin; Group 3, one dose of each of two different multivalent inactivated vaccines containing SE cells (Corymune 4K and Corymune 7K; and Group 4, unvaccinated, challenged controls. In Experiment 2, groups of broiler breeders were vaccinated by the same programmes as Groups 1 and 2 above while Group 3 was an unvaccinated, challenged control group. All vaccination programmes and the challenge induced significant (P < 0.05) seroconversion as measured by enzyme-linked immunosorbent assay. Overall, in both experiments, all vaccination schemes were significantly effective in reducing organ (spleen, liver and caeca) colonization by the challenge strain as well as reducing faecal excretion for at least 3 weeks. Vaccinated layers in Groups 1 and 2 and broiler breeders in Group 2 showed the greatest reduction in organ colonization and the least faecal excretion. In Experiment 1, layers vaccinated with multivalent inactivated vaccines containing a SE component (Group 3) were only moderately protected, indicating that such a vaccination programme may be useful in farms with good husbandry and housing conditions and low environmental infectious pressure by Salmonella.

  9. Moderate Exercise Training Attenuates the Severity of Experimental Rodent Colitis: The Importance of Crosstalk between Adipose Tissue and Skeletal Muscles

    PubMed Central

    Mazur-Bialy, Agnieszka I.; Krzysiek-Maczka, Gracjana; Urbanczyk, Katarzyna; Ptak-Belowska, Agata; Mach, Tomasz; Brzozowski, Tomasz

    2015-01-01

    Although progress has been recently made in understanding of inflammatory bowel diseases (IBD), their etiology is unknown apart from several factors from adipose tissue and skeletal muscles such as cytokines, adipokines, and myokines were implicated in the pathogenesis of ulcerative colitis. We studied the effect high-fat diet (HFD; cholesterol up to 70%), low-fat diet (LFD; cholesterol up to 10%), and the normal diet (total fat up to 5%) in rats with TNBS colitis forced to treadmill running exercise (5 days/week) for 6 weeks. In nonexercising HFD rats, the area of colonic damage, colonic tissue weight, the plasma IL-1β, TNF-α, TWEAK, and leptin levels, and the expression of IL-1β-, TNF-α-, and Hif1α mRNAs were significantly increased and a significant fall in plasma adiponectin and irisin levels was observed as compared to LFD rats. In HFD animals, the exercise significantly accelerated the healing of colitis, raised the plasma levels of IL-6 and irisin, downregulated the expression of IL-1β, TNF-α, and Hif1α, and significantly decreased the plasma IL-1β, TNF α, TWEAK, and leptin levels. We conclude that HFD delays the healing of colitis in trained rats via decrease in CBF and plasma IL-1β, TNF-α, TWEAK, and leptin levels and the release of protective irisin. PMID:25684862

  10. Therapeutic hypothermia and ischemic stroke: A literature review

    PubMed Central

    Tahir, Rizwan A.; Pabaney, Aqueel H.

    2016-01-01

    Background: Ischemic stroke is the fifth leading cause of death in the US. Clinical techniques aimed at helping to reduce the morbidity associated with stroke have been studied extensively, including therapeutic hypothermia. In this study, the authors review the literature regarding the role of therapeutic hypothermia in ischemic stroke to appreciate the evolution of hypothermia technology over several decades and to critically analyze several early clinical studies to validate its use in ischemic stroke. Methods: A comprehensive literature search was performed using PubMed and Google Scholar databases. Search terms included “hypothermia and ischemic stroke” and “therapeutic hypothermia.” A comprehensive search of the current clinical trials using clinicaltrials.gov was conducted using the keywords “stroke and hypothermia” to evaluate early and ongoing clinical trials utilizing hypothermia in ischemic stroke. Results: A comprehensive review of the evolution of hypothermia in stroke and the current status of this treatment was performed. Clinical studies were critically analyzed to appreciate their strengths and pitfalls. Ongoing and future registered clinical studies were highlighted and analyzed compared to the reported results of previous trials. Conclusion: Although hypothermia has been used for various purposes over several decades, its efficacy in the treatment of ischemic stroke is debatable. Several trials have proven its safety and feasibility; however, more robust, randomized clinical trials with large volumes of patients are needed to fully establish its utility in the clinical setting. PMID:27313963

  11. Interleukin 6 promoter 174 G/C polymorphisms in acute ischemic stroke: G allele is protective but not associated with IL-6 levels or stroke outcome.

    PubMed

    Yan, J; J M, Greer; P A, McCombe

    2016-04-15

    Our study investigated the frequency of interleukin-6 (IL-6) promoter polymorphism rs1800795 (-174 G>C), possible association of this polymorphism with IL-6 levels and the outcome after stroke in 95 patients with acute ischemic stroke and 268 healthy subjects. It shows a significant reduction in the frequency of G alleles in stroke patients compared to healthy controls. Carriage of G allele is not associated with stroke subtypes, the initial severity or the outcome after stroke. The -174 polymorphisms were not associated with variation in IL-6 levels post-stroke. Our results indicate that IL-6 promoter -174 polymorphisms may play a role in susceptibility to stroke, but not stroke outcome.

  12. Brain-Machine-Interface in Chronic Stroke Rehabilitation: A Controlled Study

    PubMed Central

    Ramos-Murguialday, Ander; Broetz, Doris; Rea, Massimiliano; Läer, Leonhard; Yilmaz, Özge; 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

    2013-01-01

    Objective Chronic stroke patients with severe hand weakness, respond poorly to rehabilitation efforts. Here, we evaluated efficacy of daily brain-machine-interface 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. Methods 32 chronic stroke patients with severe hand weakness, were randomly assigned to two matched groups and participated in 17.8 ± 1.4 days of training rewarding desynchronization of ipsilesional oscillatory sensorimotor rhythms (SMR) 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 (MRI) blood oxygenation level dependent activity were assessed before and after intervention. Results A significant group × time interaction in upper limb Fugl-Meyer motor (cFMA) 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 points 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 functional MRI laterality index and with paretic hand electromyography activity. Placebo-expectancy scores were comparable for both groups. Interpretation 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. PMID:23494615

  13. Current status of acute stroke management in Korea: a report on a multicenter, comprehensive acute stroke registry.

    PubMed

    Kim, Beom Joon; Han, Moon-Ku; Park, Tai Hwan; Park, Sang-Soon; Lee, Kyung Bok; Lee, Byung-Chul; Yu, Kyung-Ho; Cha, Jae Kwan; Kim, Dae-Hyun; Lee, Jun; Lee, Soo Joo; Ko, Youngchai; Park, Jong-Moo; Kang, Kyusik; Cho, Yong-Jin; Hong, Keun-Sik; Cho, Ki-Hyun; Kim, Joon-Tae; Kim, Dong-Eog; Lee, Juneyoung; Lee, Ji Sung; Jang, Myung Suk; Broderick, Joseph P; Yoon, Byung-Woo; Bae, Hee-Joon

    2014-06-01

    There are limited data on the utilization of diagnostics and the variation of treatments at the national level in acute stroke care. Clinical Research Center for Stroke--5th division stroke registry aimed to describe stroke statistics and quality of care in Korea and to implement quality indicators. Clinical Research Center for Stroke--5th division registry was established in April 2008 and covers pretreatment demographics, medical and stroke severity measures, diagnostic evaluation, hyperacute revascularization, in-hospital management, discharge disposition, quality indicators, and long-term functional outcomes. Consecutive stroke cases from 12 participating centers are registered to a web-based database. Meticulous data management and auditing policy were applied. A total of 14,792 ischemic stroke cases were enrolled from April 2008 to January 2012. The median National Institutes of Health Stroke Scale score was 4 at admission, with median delay of onset to arrival of 14 h. Rate of risk factor management before stroke exceeds more than 80% for hypertension and diabetes. Revascularization procedures were performed in 1736 subjects (12%), and 34% were endovascular (n = 598). Substantial variability was noted in the preferred modality of hyperacute revascularization (range of endovascular recanalization = 6-60%), use of computed tomography (30-93%), and perfusion imaging (2-96%). The Clinical Research Center for Stroke--5th division registry documented that the current practice of acute stroke care in South Korea largely met the standard of guidelines, but variability of practice still remains. The registry would provide an opportunity to evaluate the quality of stroke care across South Korea and compare it with that of other countries.

  14. Worm Proteins of Schistosoma mansoni Reduce the Severity of Experimental Chronic Colitis in Mice by Suppressing Colonic Proinflammatory Immune Responses

    PubMed Central

    Heylen, Marthe; Ruyssers, Nathalie E.; De Man, Joris G.; Timmermans, Jean-Pierre; Pelckmans, Paul A.; Moreels, Tom G.; De Winter, Benedicte Y.

    2014-01-01

    Although helminthic therapy as a possible new option to treat inflammatory bowel disease is a well-established concept by now, the search for immunomodulatory helminth-derived compounds and their mechanisms of action is still ongoing. We investigated the therapeutic potential and the underlying immunological mechanisms of Schistosoma mansoni soluble worm proteins (SmSWP) in an adoptive T cell transfer mouse model of chronic colitis. Both a curative and a preventive treatment protocol were included in this study. The curative administration of SmSWP (started when colitis was established), resulted in a significant improvement of the clinical disease score, colonoscopy, macroscopic and microscopic inflammation score, colon length and myeloperoxidase activity. The therapeutic potential of the preventive SmSWP treatment (started before colitis was established), was less pronounced compared with the curative SmSWP treatment but still resulted in an improved clinical disease score, body weight loss, colon length and microscopic inflammation score. Both the curative and preventive SmSWP treatment downregulated the mRNA expression of the proinflammatory cytokines IFN-γ and IL-17A and upregulated the mRNA expression of the anti-inflammatory cytokine IL-4 in the colon at the end of the experiment. This colonic immunomodulatory effect of SmSWP could not be confirmed at the protein level. Moreover, the effect of SmSWP appeared to be a local colonic phenomenon, since the flow cytometric T cell characterization of the mesenteric lymph nodes and the cytokine measurements in the serum did not reveal any effect of SmSWP treatment. In conclusion, SmSWP treatment reduced the severity of colitis in the adoptive transfer mouse model via the suppression of proinflammatory cytokines and the induction of an anti-inflammatory response in the colon. PMID:25313594

  15. Effects of experimental fuel additions on fire intensity and severity: unexpected carbon resilience of a neotropical forest.

    PubMed

    Brando, Paulo M; Oliveria-Santos, Claudinei; Rocha, Wanderley; Cury, Roberta; Coe, Michael T

    2016-07-01

    Global changes and associated droughts, heat waves, logging activities, and forest fragmentation may intensify fires in Amazonia by altering forest microclimate and fuel dynamics. To isolate the effects of fuel loads on fire behavior and fire-induced changes in forest carbon cycling, we manipulated fine fuel loads in a fire experiment located in southeast Amazonia. We predicted that a 50% increase in fine fuel loads would disproportionally increase fire intensity and severity (i.e., tree mortality and losses in carbon stocks) due to multiplicative effects of fine fuel loads on the rate of fire spread, fuel consumption, and burned area. The experiment followed a fully replicated randomized block design (N = 6) comprised of unburned control plots and burned plots that were treated with and without fine fuel additions. The fuel addition treatment significantly increased burned area (+22%) and consequently canopy openness (+10%), fine fuel combustion (+5%), and mortality of individuals ≥5 cm in diameter at breast height (dbh; +37%). Surprisingly, we observed nonsignificant effects of the fuel addition treatment on fireline intensity, and no significant differences among the three treatments for (i) mortality of large trees (≥30 cm dbh), (ii) aboveground forest carbon stocks, and (iii) soil respiration. It was also surprising that postfire tree growth and wood increment were higher in the burned plots treated with fuels than in the unburned control. These results suggest that (i) fine fuel load accumulation increases the likelihood of larger understory fires and (ii) single, low-intensity fires weakly influence carbon cycling of this primary neotropical forest, although delayed postfire mortality of large trees may lower carbon stocks over the long term. Overall, our findings indicate that increased fine fuel loads alone are unlikely to create threshold conditions for high-intensity, catastrophic fires during nondrought years. PMID:26750627

  16. Yin-Chen-Hao Tang Attenuates Severe Acute Pancreatitis in Rat: An Experimental Verification of In silico Network Target Prediction

    PubMed Central

    Xiang, Hong; Wang, Guijun; Qu, Jialin; Xia, Shilin; Tao, Xufeng; Qi, Bing; Zhang, Qingkai; Shang, Dong

    2016-01-01

    Yin-Chen-Hao Tang (YCHT) is a classical Chinese medicine compound that has a long history of clinical use in China for the treatment of inflammatory diseases. However, the efficacy and mechanisms of YCHT for the treatment of severe acute pancreatitis (SAP) are not known. The current study investigated the pharmacological properties of YCHT against SAP and its underlying mechanisms. A computational prediction of potential targets of YCHT was initially established based on a network pharmacology simulation. The model suggested that YCHT attenuated SAP progress by apoptosis inducement, anti-inflammation, anti-oxidation and blood lipid regulation. These effects were validated in SAP rats. YCHT administration produced the following results: (1) significantly inhibited the secretion of pancreatic enzymes and protected pancreatic tissue; (2) obviously increased the number of in situ terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL)-positive cells and induced apoptosis; (3) markedly inhibited neutrophil infiltration to the impaired pancreas and reduced the inflammatory reaction; (4) notably enhanced the activities of antioxidant enzymes and decreased the nitric oxide synthase levels; (5) significantly reduced the levels of triglycerides, total cholesterol and low-density lipoprotein and increased high-density lipoprotein; and (6) significantly up-regulated peroxisome proliferator-activated receptor-γ (PPARγ) and down-regulated nuclear factor-kappa B (NF-κB). In summary, these results demonstrated that YCHT attenuated SAP progress by inducing apoptosis, repressing inflammation, alleviating oxidative stress and regulating lipid metabolism partially via regulation of the NF-κB/PPARγ signal pathway. PMID:27790147

  17. Ethyl pyruvate therapy attenuates experimental severe arthritis caused by type II collagen (CII) in the mouse (CIA).

    PubMed

    Di Paola, R; Mazzon, E; Galuppo, M; Esposito, E; Bramanti, P; Fink, M P; Cuzzocrea, S

    2010-01-01

    This study tested the hypothesis that ethyl pyruvate (EP), a simple aliphatic ester with anti-inflammatory effects, can reduce type II collagen-induced mouse arthritis (CIA). DBA/1J mice were used for the study, developing erosive hind paw arthritis when immunized with CII in an emulsion in complete Freund?s adjuvant (CFA). The incidence of CIA was 100 percent by day 28 in the CII-challenged mice, and the severity of CIA progressed over a 35-day period with radiographic evaluation revealing focal resorption of bone. The histopathology of CIA included erosion of the cartilage at the joint margins. EP-treatment (40 mg/kg/day i.p.) starting at the onset of arthritis (day 25) ameliorated the clinical signs at days 26-35 and improved histological status in the joint and paw. Immunohistochemical analysis for nitrotyrosine, poly (ADP-ribose) (PAR), inducible nitric oxide synthase (iNOS) revealed a positive staining in inflamed joints from mice subjected to CIA, while no staining was observed for HO-1 and Nrf-2 in the same group. The degree of staining for nitrotyrosine, PAR, iNOS, was significantly reduced in CII-challenged mice treated with the EP. Immuno-positive-staining for HO-1 and Nrf-2 was observed instead, in joints obtained from the EP-treated group. Plasma levels of TNF-α, IL-6 and the joint tissue levels of macrophage inflammatory protein (MIP)-1α and MIP-2 were also significantly reduced by EP treatment. Thirty-five days after immunization, EP-treatment significantly increased plasma levels of IL-10. These data demonstrate that EP treatment exerts an anti-inflammatory effect during chronic inflammation and is able to ameliorate the tissue damage associated with CIA.

  18. Effects of experimental fuel additions on fire intensity and severity: unexpected carbon resilience of a neotropical forest.

    PubMed

    Brando, Paulo M; Oliveria-Santos, Claudinei; Rocha, Wanderley; Cury, Roberta; Coe, Michael T

    2016-07-01

    Global changes and associated droughts, heat waves, logging activities, and forest fragmentation may intensify fires in Amazonia by altering forest microclimate and fuel dynamics. To isolate the effects of fuel loads on fire behavior and fire-induced changes in forest carbon cycling, we manipulated fine fuel loads in a fire experiment located in southeast Amazonia. We predicted that a 50% increase in fine fuel loads would disproportionally increase fire intensity and severity (i.e., tree mortality and losses in carbon stocks) due to multiplicative effects of fine fuel loads on the rate of fire spread, fuel consumption, and burned area. The experiment followed a fully replicated randomized block design (N = 6) comprised of unburned control plots and burned plots that were treated with and without fine fuel additions. The fuel addition treatment significantly increased burned area (+22%) and consequently canopy openness (+10%), fine fuel combustion (+5%), and mortality of individuals ≥5 cm in diameter at breast height (dbh; +37%). Surprisingly, we observed nonsignificant effects of the fuel addition treatment on fireline intensity, and no significant differences among the three treatments for (i) mortality of large trees (≥30 cm dbh), (ii) aboveground forest carbon stocks, and (iii) soil respiration. It was also surprising that postfire tree growth and wood increment were higher in the burned plots treated with fuels than in the unburned control. These results suggest that (i) fine fuel load accumulation increases the likelihood of larger understory fires and (ii) single, low-intensity fires weakly influence carbon cycling of this primary neotropical forest, although delayed postfire mortality of large trees may lower carbon stocks over the long term. Overall, our findings indicate that increased fine fuel loads alone are unlikely to create threshold conditions for high-intensity, catastrophic fires during nondrought years.

  19. Intensive Treatment of Dysarthria Secondary to Stroke

    ERIC Educational Resources Information Center

    Mahler, Leslie A.; Ramig, Lorraine O.

    2012-01-01

    This study investigated the impact of a well-defined behavioral dysarthria treatment on acoustic and perceptual measures of speech in four adults with dysarthria secondary to stroke. A single-subject A-B-A experimental design was used to measure the effects of the Lee Silverman Voice Treatment (LSVT[R]LOUD) on the speech of individual…

  20. Ischemic Posterior Circulation Stroke: A Review of Anatomy, Clinical Presentations, Diagnosis, and Current Management

    PubMed Central

    Nouh, Amre; Remke, Jessica; Ruland, Sean

    2014-01-01

    Posterior circulation strokes represent approximately 20% of all ischemic strokes (1, 2). In contrast to the anterior circulation, several differences in presenting symptoms, clinical evaluation, diagnostic testing, and management strategy exist presenting a challenge to the treating physician. This review will discuss the anatomical, etiological, and clinical classification of PC strokes, identify diagnostic pitfalls, and overview current therapeutic regimens. PMID:24778625

  1. Stroke and High Blood Pressure

    MedlinePlus

    ... Blood Pressure Tools & Resources Stroke More Stroke and High Blood Pressure Updated:Jan 6,2015 Stroke is a leading ... to heart disease and stroke. Start exploring today ! High Blood Pressure • Home • About High Blood Pressure (HBP) • Why HBP ...

  2. Characterization of a Severe Parenchymal Phenotype of Experimental Autoimmune Encephalomyelitis in (C57BL6xB10.PL)F1 Mice

    PubMed Central

    Carrithers, Michael D.; Carrithers, Lisette M.; Czyzyk, Jan; Henegariu, Octavian

    2009-01-01

    We here describe a novel CD4 T cell adoptive transfer model of severe experimental autoimmune encephalomyelitis in (C57BL6xB10.PL)F1 mice. This FI cross developed severe disease characterized by extensive parenchymal spinal cord and brain periventricular white matter infiltrates. In contrast, B10.PL mice developed mild disease characterized by meningeal predominant infiltrates. As determined by cDNA microarray and quantitative real time PCR expression analysis, histologic and flow cytometry analysis of inflammatory infiltrates, and attenuation of disease in class I-deficient and CD8-depleted F1 mice; this severe disease phenotype appears to be regulated by CNS infiltration of CD8 T lymphocytes early in the disease course. PMID:17512611

  3. Heart Failure in Acute Ischemic Stroke

    PubMed Central

    Cuadrado-Godia, Elisa; Ois, Angel; Roquer, Jaume

    2010-01-01

    Heart failure (HF) is a complex clinical syndrome that can result from any structural or functional cardiac disorder that impairs the ability of the ventricle to fill with or eject blood. Due to the aging of the population it has become a growing public health problem in recent decades. Diagnosis of HF is clinical and there is no diagnostic test, although some basic complementary testing should be performed in all patients. Depending on the ejection fraction (EF), the syndrome is classified as HF with low EF or HF with normal EF (HFNEF). Although prognosis in HF is poor, HFNEF seems to be more benign. HF and ischemic stroke (IS) share vascular risk factors such as age, hypertension, diabetes mellitus, coronary artery disease and atrial fibrillation. Persons with HF have higher incidence of IS, varying from 1.7% to 10.4% per year across various cohort studies. The stroke rate increases with length of follow-up. Reduced EF, independent of severity, is associated with higher risk of stroke. Left ventricular mass and geometry are also related with stroke incidence, with concentric hypertrophy carrying the greatest risk. In HF with low EF, the stroke mechanism may be embolism, cerebral hypoperfusion or both, whereas in HFNEF the mechanism is more typically associated with chronic endothelial damage of the small vessels. Stroke in patients with HF is more severe and is associated with a higher rate of recurrence, dependency, and short term and long term mortality. Cardiac morbidity and mortality is also high in these patients. Acute stroke treatment in HF includes all the current therapeutic options to more carefully control blood pressure. For secondary prevention, optimal control of all vascular risk factors is essential. Antithrombotic therapy is mandatory, although the choice of a platelet inhibitor or anticoagulant drug depends on the cardiac disease. Trials are ongoing to evaluate anticoagulant therapy for prevention of embolism in patients with low EF who are at

  4. The Migraine–Stroke Connection

    PubMed Central

    Lee, Mi Ji; Lee, Chungbin; Chung, Chin-Sang

    2016-01-01

    Migraine and stroke are common neurovascular disorders which share underlying physiological processes. Increased risks of ischemic stroke, hemorrhagic stroke, and subclinical ischemic lesions have been consistently found in migraineurs. Three possible associations are suggested. One is that underlying pathophysiology of migraine can lead to ischemic stroke. Second, common comorbidities between migraine and stroke can be present. Lastly, some syndromes can manifest with both migraine-like headache and cerebrovascular disease. Future studies should be targeted on bidirectional influence of migraine on different stroke mechanisms and optimal prevention of stroke in migraine patients. PMID:27283278

  5. Hyponatremia in stroke

    PubMed Central

    Saleem, Sheikh; Yousuf, Irfan; Gul, Azhara; Gupta, Satish; Verma, Sawan

    2014-01-01

    Introduction: Hyponatremia is a common electrolyte disorder encountered in patients of neurological disorders which is usually either due to inappropriate secretion of Antidiuretic hormone (SIADH) or cerebral salt wasting syndrome (CSWS). We conducted this study in a tertiary care hospital to determine the incidence and etiology of hyponatremia in patients of stroke admitted in the hospital. Materials and Methods: It was a prospective study done over a period of two years that included established cases of stroke diagnosed on the basis of clinical history, examination and neuroimaging. 1000 stoke patients were evaluated for hyponatremia (serum sodium <130 meq/l). The data was analysed using Chi-square test using SPSS (Statistical package for social science) software. Results: Out of 1000 patients, 353 patients had hyponatremia. Out of this 353 patients, 238 (67%) had SIADH and 115 (33%) had CSWS. SIADH was seen in 83 patients who had ischemic stroke and 155 patients of hemorrhagic stroke. CSWS was found in 38 patients with ischemic stroke and 77 patients with hemorrhagic stroke. Statistical analysis revealed that hyponatremia significantly affects the outcome of stroke especially when it is due to CSWS rather than SIADH. Conclusion: Incidence of hyponatremia in our study population was 35%. In patients of hyponatremia 67% were having SIADH and 33% were having CSWS. Overall hyponatremia affected the outcome of stroke especially when caused by CSWS. Therefore close monitoring of serum sodium must be done in all patients who are admitted with stroke and efforts must be made to determine the cause of hyponatremia, in order to properly manage such patients thereby decreasing the mortality rate. PMID:24753660

  6. [Obesity Paradox and Stroke].

    PubMed

    Baumgartner, Ralf; Oesch, Lisa; Sarikaya, Hakan

    2016-07-01

    The obesity paradox suggests that overweight and obese patients of older age may have higher survival rates after stroke as compared to normalweight patients. However, the results need a cautious interpretation due to selection bias, treatment bias and different patients’ characteristics. Moreover, randomized studies that prove a benefit of weight reduction are still lacking. As obesity is an independet risk factor for stroke, weight reduction should still be recommended in overweight patients. Randomized-controlled studies are needed to prove the effect of weight reduction on morbidity and mortality after stroke. PMID:27381308

  7. Newer Oral Anticoagulants: Stroke Prevention and Pitfalls

    PubMed Central

    Patel, Anand; Goddeau Jr, Richard P.; Henninger, Nils

    2016-01-01

    Warfarin is very effective in preventing stroke in patients with atrial fibrillation. However, its use is limited due to fear of hemorrhagic complications, unpredictable anticoagulant effects related to multiple drug interactions and dietary restrictions, a narrow therapeutic window, frequent difficulty maintaining the anticoagulant effect within a narrow therapeutic window, and the need for inconvenient monitoring. Several newer oral anticoagulants have been approved for primary and secondary prevention of stroke in patients with non-valvular atrial fibrillation. These agents have several advantages relative to warfarin therapy. As a group, these direct oral anticoagulants (DOAC), which include the direct thrombin inhibitor, dabigatran, and the factor Xa inhibitors (rivaroxaban, apixaban, and edoxaban), are more effective than dose adjusted warfarin for prevention of all-cause stroke (including both ischemic and hemorrhagic stroke), and have an overall more favorable safety profile. Nevertheless, an increased risk of gastrointestinal bleeding (with the exception of apixaban), increased risk for thrombotic complication with sudden discontinuation, and inability to accurately assess and reverse anticoagulant effect require consideration prior to therapy initiation, and pose a challenge for decision making in acute stroke therapy. PMID:27347226

  8. Antithrombotic Medication for Cardioembolic Stroke Prevention

    PubMed Central

    Font, M. Àngels; Krupinski, Jerzy; Arboix, Adrià

    2011-01-01

    Embolism of cardiac origin accounts for about 20% of ischemic strokes. Nonvalvular atrial fibrillation is the most frequent cause of cardioembolic stroke. Approximately 1% of population is affected by atrial fibrillation, and its prevalence is growing with ageing in the modern world. Strokes due to cardioembolism are in general severe and prone to early recurrence and have a higher long-term risk of recurrence and mortality. Despite its enormous preventive potential, continuous oral anticoagulation is prescribed for less than half of patients with atrial fibrillation who have risk factors for cardioembolism and no contraindications for anticoagulation. Available evidence does not support routine immediate anticoagulation of acute cardioembolic stroke. Anticoagulation therapy's associated risk of hemorrhage and monitoring requirements have encouraged the investigation of alternative therapies for individuals with atrial fibrillation. New anticoagulants being tested for prevention of stroke are low-molecular-weight heparins (LMWH), unfractionated heparin, factor Xa inhibitors, or direct thrombin inhibitors like dabigatran etexilate and rivaroxaban. The later exhibit stable pharmacokinetics obviating the need for coagulation monitoring or dose titration, and they lack clinically significant food or drug interaction. Moreover, they offer another potential that includes fixed dosing, oral administration, and rapid onset of action. There are several concerns regarding potential harm, including an increased risk for hepatotoxicity, clinically significant bleeding, and acute coronary events. Therefore, additional trials and postmarketing surveillance will be needed. PMID:21822469

  9. Assimilation of Web-Based Urgent Stroke Evaluation: A Qualitative Study of Two Networks

    PubMed Central

    Mathiassen, Lars; Switzer, Jeffrey A; Adams, Robert J

    2014-01-01

    Background Stroke is a leading cause of death and serious, long-term disability across the world. Urgent stroke care treatment is time-sensitive and requires a stroke-trained neurologist for clinical diagnosis. Rural areas, where neurologists and stroke specialists are lacking, have a high incidence of stroke-related death and disability. By virtually connecting emergency department physicians in rural hospitals to regional medical centers for consultations, specialized Web-based stroke evaluation systems (telestroke) have helped address the challenge of urgent stroke care in underserved communities. However, many rural hospitals that have deployed telestroke have not fully assimilated this technology. Objective The objective of this study was to explore potential sources of variations in the utilization of a Web-based telestroke system for urgent stroke evaluation and propose a telestroke assimilation model to improve stroke care performance. Methods An exploratory, qualitative case study of two telestroke networks, each comprising an academic stroke center (hub) and connected rural hospitals (spokes), was conducted. Data were collected from 50 semistructured interviews with 40 stakeholders, telestroke usage logs from 32 spokes, site visits, published papers, and reports. Results The two networks used identical technology (called Remote Evaluation of Acute isCHemic stroke, REACH) and were of similar size and complexity, but showed large variations in telestroke assimilation across spokes. Several observed hub- and spoke-related characteristics can explain these variations. The hub-related characteristics included telestroke institutionalization into stroke care, resources for the telestroke program, ongoing support for stroke readiness of spokes, telestroke performance monitoring, and continuous telestroke process improvement. The spoke-related characteristics included managerial telestroke championship, stroke center certification, dedicated telestroke

  10. Functional recovery after stroke: a review of current developments in stroke rehabilitation research.

    PubMed

    Kollen, Boudewijn; Kwakkel, Gert; Lindeman, Eline

    2006-01-01

    This review article discusses current research developments in functional recovery after stroke. With the institutionalization of stroke services across health care facilities, a reduction in mortality rates, length of inpatient stay and improved independence in activities of daily living has been reported. Several systematic reviews show that traditional treatment approaches induce improvements that are confined to impairment level only and do not generalize to a functional improvement level. More recently developed treatment strategies that incorporate compensation strategies with a strong emphasis on functional training, may hold the key to optimal stroke rehabilitation. Intensity and task-specific exercise therapy are important components of such an approach. Guidelines may assist the clinician in this responsibility. However, due to marked heterogeneity of the stroke population and poor methodological quality of many studies, results are uncertain. Several options are discussed to overcome the problem of stroke heterogeneity in research designs. Longitudinal repeated measurements designs are required to study the effects of non-linearity and time dependency of functional recovery in stroke. Furthermore, prognostic research based on sound clinimetric data generates relevant information that may guide the clinician in clinical decision making and in determining optimal treatment strategies.

  11. Post-stroke language disorders.

    PubMed

    Sinanović, Osman; Mrkonjić, Zamir; Zukić, Sanela; Vidović, Mirjana; Imamović, Kata

    2011-03-01

    Post-stroke language disorders are frequent and include aphasia, alexia, agraphia and acalculia. There are different definitions of aphasias, but the most widely accepted neurologic and/or neuropsychological definition is that aphasia is a loss or impairment of verbal communication, which occurs as a consequence of brain dysfunction. It manifests as impairment of almost all verbal abilities, e.g., abnormal verbal expression, difficulties in understanding spoken or written language, repetition, naming, reading and writing. During the history, many classifications of aphasia syndromes were established. For practical use, classification of aphasias according to fluency, comprehension and abilities of naming it seems to be most suitable (nonfluent aphasias: Broca's, transcortical motor, global and mixed transcortical aphasia; fluent aphasias: anomic, conduction, Wernicke's, transcortical sensory, subcortical aphasia). Aphasia is a common consequence of left hemispheric lesion and most common neuropsychological consequence of stroke, with a prevalence of one-third of all stroke patients in acute phase, although there are reports on even higher figures. Many speech impairments have a tendency of spontaneous recovery. Spontaneous recovery is most remarkable in the first three months after stroke onset. Recovery of aphasias caused by ischemic stroke occurs earlier and it is most intensive in the first two weeks. In aphasias caused by hemorrhagic stroke, spontaneous recovery is slower and occurs from the fourth to the eighth week after stroke. The course and outcome of aphasia depend greatly on the type of aphasia. Regardless of the fact that a significant number of aphasias spontaneously improve, it is necessary to start treatment as soon as possible. The writing and reading disorders in stroke patients (alexias and agraphias) are more frequent than verified on routine examination, not only in less developed but also in large neurologic departments. Alexia is an acquired

  12. Post-stroke language disorders.

    PubMed

    Sinanović, Osman; Mrkonjić, Zamir; Zukić, Sanela; Vidović, Mirjana; Imamović, Kata

    2011-03-01

    Post-stroke language disorders are frequent and include aphasia, alexia, agraphia and acalculia. There are different definitions of aphasias, but the most widely accepted neurologic and/or neuropsychological definition is that aphasia is a loss or impairment of verbal communication, which occurs as a consequence of brain dysfunction. It manifests as impairment of almost all verbal abilities, e.g., abnormal verbal expression, difficulties in understanding spoken or written language, repetition, naming, reading and writing. During the history, many classifications of aphasia syndromes were established. For practical use, classification of aphasias according to fluency, comprehension and abilities of naming it seems to be most suitable (nonfluent aphasias: Broca's, transcortical motor, global and mixed transcortical aphasia; fluent aphasias: anomic, conduction, Wernicke's, transcortical sensory, subcortical aphasia). Aphasia is a common consequence of left hemispheric lesion and most common neuropsychological consequence of stroke, with a prevalence of one-third of all stroke patients in acute phase, although there are reports on even higher figures. Many speech impairments have a tendency of spontaneous recovery. Spontaneous recovery is most remarkable in the first three months after stroke onset. Recovery of aphasias caused by ischemic stroke occurs earlier and it is most intensive in the first two weeks. In aphasias caused by hemorrhagic stroke, spontaneous recovery is slower and occurs from the fourth to the eighth week after stroke. The course and outcome of aphasia depend greatly on the type of aphasia. Regardless of the fact that a significant number of aphasias spontaneously improve, it is necessary to start treatment as soon as possible. The writing and reading disorders in stroke patients (alexias and agraphias) are more frequent than verified on routine examination, not only in less developed but also in large neurologic departments. Alexia is an acquired

  13. Inflammation severely alters thyroid hormone signaling in the central nervous system during experimental allergic encephalomyelitis in rat: Direct impact on OPCs differentiation failure.

    PubMed

    Fernández, Mercedes; Baldassarro, Vito A; Sivilia, Sandra; Giardino, Luciana; Calzà, Laura

    2016-09-01

    Differentiation of oligodendrocyte precursor cells (OPCs) into myelinating oligodendrocytes is severely impaired by inflammatory cytokines and this could lead to remyelination failure in inflammatory/demyelinating diseases. Due to the role of thyroid hormone in the maturation of OPCs and developmental myelination, in this study we investigated (i) the possible occurrence of dysregulation of thyroid hormone signaling in the CNS tissue during experimental neuroinflammation; (ii) the possible impact of inflammatory cytokines on thyroid hormone signaling and OPCs differentiation in vitro. The disease model is the experimental allergic encephalomyelitis in female Dark-Agouti rats, whereas in vitro experiments were carried out in OPCs derived from neural stem cells. The main results are the following: (i) a strong upregulation of cytokine mRNA expression level was found in the spinal cord during experimental allergic encephalomyelitis; (ii) thyroid hormone signaling in the spinal cord (thyroid hormone receptors; deiodinase; thyroid hormone membrane transporter) is substantially downregulated, due to the upregulation of the thyroid hormone inactivating enzyme deiodinase 3 and the downregulation of thyroid hormone receptors, as investigated at mRNA expression level; (iii) when exposed to inflammatory cytokines, deiodinase 3 is upregulated in OPCs as well, and OPCs differentiation is blocked; (iv) deiodinase 3 inhibition by iopanoic acid recovers OPCs differentiation in the presence on inflammatory cytokines. These data suggest that cellular hypothyroidism occurs during experimental allergic encephalomyelitis, possibly impacting on thyroid hormone-dependent cellular processes, including maturation of OPCs into myelinating oligodendrocytes. GLIA 2016;64:1573-1589. PMID:27404574

  14. Conditional ablation of myeloid TNF increases lesion volume after experimental stroke in mice, possibly via altered ERK1/2 signaling

    PubMed Central

    Clausen, Bettina Hjelm; Degn, Matilda; Sivasaravanaparan, Mithula; Fogtmann, Torben; Andersen, Maria Gammelstrup; Trojanowsky, Michelle D.; Gao, Han; Hvidsten, Svend; Baun, Christina; Deierborg, Tomas; Finsen, Bente; Kristensen, Bjarne Winther; Bak, Sara Thornby; Meyer, Morten; Lee, Jae; Nedospasov, Sergei A.; Brambilla, Roberta; Lambertsen, Kate Lykke

    2016-01-01

    Microglia are activated following cerebral ischemia and increase their production of the neuro- and immunomodulatory cytokine tumor necrosis factor (TNF). To address the function of TNF from this cellular source in focal cerebral ischemia we used TNF conditional knock out mice (LysMcreTNFfl/fl) in which the TNF gene was deleted in cells of the myeloid lineage, including microglia. The deletion reduced secreted TNF levels in lipopolysaccharide-stimulated cultured primary microglia by ~93%. Furthermore, phosphorylated-ERK/ERK ratios were significantly decreased in naïve LysMcreTNFfl/fl mice demonstrating altered ERK signal transduction. Micro-PET using 18[F]-fluorodeoxyglucose immediately after focal cerebral ischemia showed increased glucose uptake in LysMcreTNFfl/fl mice, representing significant metabolic changes, that translated into increased infarct volumes at 24 hours and 5 days compared to littermates (TNFfl/fl). In naïve LysMcreTNFfl/fl mice cytokine levels were low and comparable to littermates. At 6 hours, TNF producing microglia were reduced by 56% in the ischemic cortex in LysMcreTNFfl/fl mice compared to littermate mice, whereas no TNF+ leukocytes were detected. At 24 hours, pro-inflammatory cytokine (TNF, IL-1β, IL-6, IL-5 and CXCL1) levels were significantly lower in LysMcreTNFfl/fl mice, despite comparable infiltrating leukocyte populations. Our results identify microglial TNF as beneficial and neuroprotective in the acute phase and as a modulator of neuroinflammation at later time points after experimental ischemia, which may contribute to regenerative recovery. PMID:27384243

  15. Conditional ablation of myeloid TNF increases lesion volume after experimental stroke in mice, possibly via altered ERK1/2 signaling.

    PubMed

    Clausen, Bettina Hjelm; Degn, Matilda; Sivasaravanaparan, Mithula; Fogtmann, Torben; Andersen, Maria Gammelstrup; Trojanowsky, Michelle D; Gao, Han; Hvidsten, Svend; Baun, Christina; Deierborg, Tomas; Finsen, Bente; Kristensen, Bjarne Winther; Bak, Sara Thornby; Meyer, Morten; Lee, Jae; Nedospasov, Sergei A; Brambilla, Roberta; Lambertsen, Kate Lykke

    2016-01-01

    Microglia are activated following cerebral ischemia and increase their production of the neuro- and immunomodulatory cytokine tumor necrosis factor (TNF). To address the function of TNF from this cellular source in focal cerebral ischemia we used TNF conditional knock out mice (LysMcreTNF(fl/fl)) in which the TNF gene was deleted in cells of the myeloid lineage, including microglia. The deletion reduced secreted TNF levels in lipopolysaccharide-stimulated cultured primary microglia by ~93%. Furthermore, phosphorylated-ERK/ERK ratios were significantly decreased in naïve LysMcreTNF(fl/fl) mice demonstrating altered ERK signal transduction. Micro-PET using (18)[F]-fluorodeoxyglucose immediately after focal cerebral ischemia showed increased glucose uptake in LysMcreTNF(fl/fl) mice, representing significant metabolic changes, that translated into increased infarct volumes at 24 hours and 5 days compared to littermates (TNFfl/fl). In naïve LysMcreTNF(fl/fl) mice cytokine levels were low and comparable to littermates. At 6 hours, TNF producing microglia were reduced by 56% in the ischemic cortex in LysMcreTNF(fl/fl) mice compared to littermate mice, whereas no TNF(+) leukocytes were detected. At 24 hours, pro-inflammatory cytokine (TNF, IL-1β, IL-6, IL-5 and CXCL1) levels were significantly lower in LysMcreTNF(fl/fl) mice, despite comparable infiltrating leukocyte populations. Our results identify microglial TNF as beneficial and neuroprotective in the acute phase and as a modulator of neuroinflammation at later time points after experimental ischemia, which may contribute to regenerative recovery. PMID:27384243

  16. Length of Hospital Stay After Stroke: A Korean Nationwide Study

    PubMed Central

    2016-01-01

    Objective To investigate the length of hospital stay (LOS) after stroke using the database of the Korean Health Insurance Review & Assessment Service. Methods We matched the data of patients admitted for ischemic stroke onset within 7 days in the Departments of Neurology of 12 hospitals to the data from the database of the Korean Health Insurance Review & Assessment Service. We recruited 3,839 patients who were hospitalized between January 2011 and December 2011, had a previous modified Rankin Scale of 0, and no acute hospital readmission after discharge. The patients were divided according to the initial National Institute of Health Stroke Scale score (mild, ≤5; moderate, >5 and ≤13; severe, >13); we compared the number of hospitals that admitted patients and LOS after stroke according to severity, age, and sex. Results The mean LOS was 115.6±219.0 days (median, 19.4 days) and the mean number of hospitals was 3.3±2.1 (median, 2.0). LOS was longer in patients with severe stroke (mild, 65.1±146.7 days; moderate, 223.1±286.0 days; and severe, 313.2±336.8 days). The number of admitting hospitals was greater for severe stroke (mild, 2.9±1.7; moderate, 4.3±2.6; and severe, 4.5±2.4). LOS was longer in women and shorter in patients less than 65 years of age. Conclusion LOS after stroke differed according to the stroke severity, sex, and age. These results will be useful in determining the appropriate LOS after stroke in the Korean medical system.

  17. Length of Hospital Stay After Stroke: A Korean Nationwide Study

    PubMed Central

    2016-01-01

    Objective To investigate the length of hospital stay (LOS) after stroke using the database of the Korean Health Insurance Review & Assessment Service. Methods We matched the data of patients admitted for ischemic stroke onset within 7 days in the Departments of Neurology of 12 hospitals to the data from the database of the Korean Health Insurance Review & Assessment Service. We recruited 3,839 patients who were hospitalized between January 2011 and December 2011, had a previous modified Rankin Scale of 0, and no acute hospital readmission after discharge. The patients were divided according to the initial National Institute of Health Stroke Scale score (mild, ≤5; moderate, >5 and ≤13; severe, >13); we compared the number of hospitals that admitted patients and LOS after stroke according to severity, age, and sex. Results The mean LOS was 115.6±219.0 days (median, 19.4 days) and the mean number of hospitals was 3.3±2.1 (median, 2.0). LOS was longer in patients with severe stroke (mild, 65.1±146.7 days; moderate, 223.1±286.0 days; and severe, 313.2±336.8 days). The number of admitting hospitals was greater for severe stroke (mild, 2.9±1.7; moderate, 4.3±2.6; and severe, 4.5±2.4). LOS was longer in women and shorter in patients less than 65 years of age. Conclusion LOS after stroke differed according to the stroke severity, sex, and age. These results will be useful in determining the appropriate LOS after stroke in the Korean medical system. PMID:27606274

  18. Pediatric Stroke: A Review

    PubMed Central

    Tsze, Daniel S.; Valente, Jonathan H.

    2011-01-01

    Stroke is relatively rare in children, but can lead to significant morbidity and mortality. Understanding that children with strokes present differently than adults and often present with unique risk factors will optimize outcomes in children. Despite an increased incidence of pediatric stroke, there is often a delay in diagnosis, and cases may still remain under- or misdiagnosed. Clinical presentation will vary based on the child's age, and children will have risk factors for stroke that are less common than in adults. Management strategies in children are extrapolated primarily from adult studies, but with different considerations regarding short-term anticoagulation and guarded recommendations regarding thrombolytics. Although most recommendations for management are extrapolated from adult populations, they still remain useful, in conjunction with pediatric-specific considerations. PMID:22254140

  19. ALTERED PHALANX FORCE DIRECTION DURING POWER GRIP FOLLOWING STROKE

    PubMed Central

    Enders, Leah R.

    2015-01-01

    Many stroke survivors with severe impairment can grasp only with a power grip. Yet, little knowledge is available on altered power grip after stroke, other than reduced power grip strength. This study characterized stroke survivors’ static power grip during 100% and 50% maximum grip. Each phalanx force’s angular deviation from the normal direction and its contribution to total normal force was compared for 11 stroke survivors and 11 age-matched controls. Muscle activities and skin coefficient of friction (COF) were additionally compared for another 20 stroke and 13 age-matched control subjects. The main finding was that stroke survivors gripped with a 34% greater phalanx force angular deviation of 19±2° compared to controls of 14±1° (p<.05). Stroke survivors’ phalanx force angular deviation was closer to the 23° threshold of slippage between the phalanx and grip surface, which may explain increased likelihood of object dropping in stroke survivors. In addition, this altered phalanx force direction decreases normal grip force by tilting the force vector, indicating a partial role of phalanx force angular deviation in reduced grip strength post stroke. Greater phalanx force angular deviation may biomechanically result from more severe underactivation of stroke survivors’ first dorsal interosseous (FDI) and extensor digitorum communis (EDC) muscles compared to their flexor digitorum superficialis (FDS) or somatosensory deficit. While stroke survivors’ maximum power grip strength was approximately half of the controls’, the distribution of their remaining strength over the fingers and phalanges did not differ, indicating evenly distributed grip force reduction over the entire hand. PMID:25795079

  20. Endocarditis and stroke.

    PubMed

    Grecu, Nicolae; Tiu, Cristina; Terecoasa, Elena; Bajenaru, Ovidiu

    2014-12-01

    Endocarditis is an important, although less common, cause of cerebral embolism. All forms of endocarditis share an initial common pathophysiologic pathway, best illustrated by the non-bacterial thrombotic form, but also a final potential for embolization. Stroke associated with endocarditis has signifficant mortality and morbidity rates, especially due to the frequent concomitant multiple sites of brain embolization. In this article we aim to briefly review endocarditis with a focus on stroke as a complication, while also presenting case correlates from our department.

  1. Microcomputer-based Acceleration Sensor Device for Swimming Stroke Monitoring

    NASA Astrophysics Data System (ADS)

    Ohgi, Yuji; Ichikawa, Hiroshi; Miyaji, Chikara

    The purpose of this study was to develop a microcomputer-based acceleration logger device for the swimming stroke monitoring. The authors measured the swimmer's tri-axial wrist acceleration and applied this device for the fatigue evaluation of the swimmers. The experimental protocol led the swimmers exhausted after the crawl stroke interval training. Every single stroke was determined by the impact acceleration peak, which appeared on the x and z-axis acceleration. The change of the underwater stroke phases was identified by the characteristics of the acceleration peaks. In their exhaustion, the y-axis acceleration, which was longitudinal forearm acceleration decreased at the beginning of the upsweep phase. At that time, the swimmer could not extend his elbow joint. Since the developed acceleration data logger could provide us the information about the underwater stroke phases and it would be a helpful tool in the swimming training.

  2. Induction of severe experimental autoimmune neuritis with a synthetic peptide corresponding to the 53-78 amino acid sequence of the myelin P2 protein.

    PubMed

    Rostami, A; Gregorian, S K; Brown, M J; Pleasure, D E

    1990-12-01

    We generated a synthetic peptide (SP-26), corresponding to the amino acid residues 53-78 of bovine P2 protein, which induced severe clinical and pathological characteristics of experimental autoimmune neuritis (EAN) in Lewis rats. Lymph node cell populations from SP-26-immunized rats elicited a proliferative response to the peptide and to the P2 protein. After 16 cycles of antigen stimulation with the peptide, the SP-26 T cell line shows a decreased response to P2, but not to SP-26. Fluorescence-activated cell sorter (FACS) analysis of a SP-26 T cell line indicated the majority of cells to be of CD4+ CD8-. This report demonstrates that the synthetic peptide SP-26 can induce severe EAN in Lewis rats in a dose-dependent manner. Furthermore, specific T cell lines reactive to SP-26 can be generated from the lymph nodes of SP-26-immunized rats. PMID:1699975

  3. Induction of severe experimental autoimmune neuritis with a synthetic peptide corresponding to the 53-78 amino acid sequence of the myelin P2 protein.

    PubMed

    Rostami, A; Gregorian, S K; Brown, M J; Pleasure, D E

    1990-12-01

    We generated a synthetic peptide (SP-26), corresponding to the amino acid residues 53-78 of bovine P2 protein, which induced severe clinical and pathological characteristics of experimental autoimmune neuritis (EAN) in Lewis rats. Lymph node cell populations from SP-26-immunized rats elicited a proliferative response to the peptide and to the P2 protein. After 16 cycles of antigen stimulation with the peptide, the SP-26 T cell line shows a decreased response to P2, but not to SP-26. Fluorescence-activated cell sorter (FACS) analysis of a SP-26 T cell line indicated the majority of cells to be of CD4+ CD8-. This report demonstrates that the synthetic peptide SP-26 can induce severe EAN in Lewis rats in a dose-dependent manner. Furthermore, specific T cell lines reactive to SP-26 can be generated from the lymph nodes of SP-26-immunized rats.

  4. Coupling of Neurogenesis and Angiogenesis After Ischemic Stroke

    PubMed Central

    Ruan, Linhui; Wang, Brian; ZhuGe, Qichuan; Jin, Kunlin

    2015-01-01

    Stroke is a leading cause of mortality and severe long-term disability worldwide. Development of effective treatment or new therapeutic strategies for ischemic stroke patients is therefore crucial. Ischemic stroke promotes neurogenesis by several growth factors including FGF-2, IGF-1, BDNF, VEGF and chemokines including SDF-1, MCP-1. Stroke-induced angiogenesis is similarly regulated by many factors most notably, eNOS and CSE, VEGF/VEGFR2, and Ang-1/Tie2. Important findings in the last decade have revealed that neurogenesis is not the stand-alone consideration in the fight for full functional recovery from stroke. Angiogenesis has been also shown to be critical in improving post-stroke neurological functional recovery. More than that, recent evidence has shown a highly possible interplay or dependence between stroke-induced neurogenesis and angiogenesis. Moving forward, elucidating the underlying mechanisms of this coupling between stroke-induced neurogenesis and angiogenesis will be of great importance, which will provide the basis for neurorestorative therapy. PMID:25736182

  5. Family History and Functional Outcome in Korean Stroke Patients: A Preliminary Study

    PubMed Central

    Park, Hee Jung; Kim, Tae Uk; Hyun, Jung Keun

    2015-01-01

    Objective To investigate the association of family history of stroke with functional outcomes in stroke patients in Korea. Methods A case-control study was conducted. A total of 170 patients who were admitted to a rehabilitation unit were included. Risk factors for stroke such as age, sex, diabetes mellitus, hypertension, atrial fibrillation, smoking, high blood cholesterol and homocysteine level, obesity, and family history of stroke were taken into account. Stroke subtypes were the following: large vessel infarct, small vessel infarct, embolic infarct, subarachnoid hemorrhage, and intracranial hemorrhage. Stroke severity as assessed with the National Institutes of Health Stroke Scale (NIHSS), functional outcomes using the Korean version of the Modified Barthel index (K-MBI), Functional Independence Measurement (FIM), and cognitive function using the Korean version of Mini-Mental State Examination (K-MMSE) were assessed at admission and discharge. Results Subjects with a family history of stroke were more likely to have an ischemic stroke (90.7%) than were those without a family history (70.9%). The K-MBI, FIM, NIHSS, and K-MMSE scores did not show significant differences between patients with or without family history. Conclusion Family history of stroke was significantly associated with ischemic stroke, but not with functional outcomes. Other prognostic factors of stroke were not distributed differently between patients included in this study with or without a family history of stroke. PMID:26798613

  6. World Stroke Organization global stroke services guidelines and action plan.

    PubMed

    Lindsay, Patrice; Furie, Karen L; Davis, Stephen M; Donnan, Geoffrey A; Norrving, Bo

    2014-10-01

    Every two seconds, someone across the globe suffers a symptomatic stroke. 'Silent' cerebrovascular disease insidiously contributes to worldwide disability by causing cognitive impairment in the elderly. The risk of cerebrovascular disease is disproportionately higher in low to middle income countries where there may be barriers to stroke care. The last two decades have seen a major transformation in the stroke field with the emergence of evidence-based approaches to stroke prevention, acute stroke management, and stroke recovery. The current challenge lies in implementing these interventions, particularly in regions with high incidences of stroke and limited healthcare resources. The Global Stroke Services Action Plan was conceived as a tool to identifying key elements in stroke care across a continuum of health models. At the minimal level of resource availability, stroke care delivery is based at a local clinic staffed predominantly by non-physicians. In this environment, laboratory tests and diagnostic studies are scarce, and much of the emphasis is placed on bedside clinical skills, teaching, and prevention. The essential services level offers access to a CT scan, physicians, and the potential for acute thrombolytic therapy, however stroke expertise may still be difficult to access. At the advanced stroke services level, multidisciplinary stroke expertise, multimodal imaging, and comprehensive therapies are available. A national plan for stroke care should incorporate local and regional strengths and build upon them. This clinical practice guideline is a synopsis of the core recommendations and quality indicators adapted from ten high quality multinational stroke guidelines. It can be used to establish the current level of stroke services, target goals for expanding stroke resources, and ensuring that all stages of stroke care are being adequately addressed, even at the advanced stroke services level. This document is a start, but there is more to be done

  7. World Stroke Organization global stroke services guidelines and action plan.

    PubMed

    Lindsay, Patrice; Furie, Karen L; Davis, Stephen M; Donnan, Geoffrey A; Norrving, Bo

    2014-10-01

    Every two seconds, someone across the globe suffers a symptomatic stroke. 'Silent' cerebrovascular disease insidiously contributes to worldwide disability by causing cognitive impairment in the elderly. The risk of cerebrovascular disease is disproportionately higher in low to middle income countries where there may be barriers to stroke care. The last two decades have seen a major transformation in the stroke field with the emergence of evidence-based approaches to stroke prevention, acute stroke management, and stroke recovery. The current challenge lies in implementing these interventions, particularly in regions with high incidences of stroke and limited healthcare resources. The Global Stroke Services Action Plan was conceived as a tool to identifying key elements in stroke care across a continuum of health models. At the minimal level of resource availability, stroke care delivery is based at a local clinic staffed predominantly by non-physicians. In this environment, laboratory tests and diagnostic studies are scarce, and much of the emphasis is placed on bedside clinical skills, teaching, and prevention. The essential services level offers access to a CT scan, physicians, and the potential for acute thrombolytic therapy, however stroke expertise may still be difficult to access. At the advanced stroke services level, multidisciplinary stroke expertise, multimodal imaging, and comprehensive therapies are available. A national plan for stroke care should incorporate local and regional strengths and build upon them. This clinical practice guideline is a synopsis of the core recommendations and quality indicators adapted from ten high quality multinational stroke guidelines. It can be used to establish the current level of stroke services, target goals for expanding stroke resources, and ensuring that all stages of stroke care are being adequately addressed, even at the advanced stroke services level. This document is a start, but there is more to be done

  8. [Management of blood pressure for stroke prevention].

    PubMed

    Tanahashi, Norio

    2016-04-01

    Hypertension is a major risk factor for both cerebral infarction and intracerebral hemorrhage. The relationship between blood pressure (BP) and stroke risk is strong and continuous. Throughout the usual range of BPs, including the nonhypertensive range, the higher the BP is, the greater the risk of stroke. Regular BP screening and appropriate treatment of patients with hypertension, including life style modification and pharmacotherapy, are recommended. Patients who have hypertension should be treated with antihypertensive drugs to a target BP of < 140/90 mmHg. Successful reduction of BP is more important in reducing stroke risk than the choice of a specific agent, and treatment should be individualized on the basis of other patient characteristics and medication tolerance. In hypertensive patients with stroke, subjects to be treated with antihypertensive drugs and the target level of BP control are determined on the basis of clinical disease type, interval after onset, severity, age, and the use of antithrombotic. drugs. According to the guideline of the Japanese Society of Hypertension (JSH 2014), in the chronic phase of cerebral infarction, cerebral hemorrhage and subarachnoid hemorrhage, target BP should be < 140/ 90 mmHg. In patients with lacunar infarction, those taking antithrombotic drugs, cerebral hemorrhage and subarachnoid hemorrhage, a lower level, < 130/80 mmHg should be targeted if possible. Oral antihypertensive drugs such as Ca channel blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers and diuretics are recommended for patients with stroke. PMID:27333760

  9. Real-time optoacoustic monitoring of stroke

    NASA Astrophysics Data System (ADS)

    Kneipp, Moritz; Turner, Jake; Hambauer, Sebastian; Krieg, Sandro M.; Lehmberg, Jens; Lindauer, Ute; Razansky, Daniel

    2014-03-01

    Characterizing disease progression and identifying possible therapeutic interventions in stroke is greatly aided by the use of longitudinal function imaging studies. In this study, we investigate the applicability of real-time multispectral optoacoustic tomography (MSOT) as a tool for non-invasive monitoring of the progression of stroke in the whole brain. The middle cerebral artery occlusion (MCAO) method was used to induce stroke. Mice were imaged under isoflurane anesthesia preoperatively and at several time points during and after the 60-minute occlusion. The animals were sacrificed after 24 hours and their excised brains frozen at -80°C for sectioning. The cryosection were stained using H&E staining to identify the ischemic lesion. Major vessels are readily identifiable in the whole mouse head in the in vivo optoacoustic scans. During ischemia, a reduction in cerebral blood volume is detectable in the cortex. Post ischemia, spectral unmixing of the optoacoustic signals shows an asymmetry of the deoxygenated hemoglobin in the hemisphere affected by MCAO. This hypoxic area was mainly located around the boundary of the ischemic lesion and was therefore identified as the ischemic penumbra. Non-invasive functional MSOT imaging is able to visualize the hypoxic penumbra in brains affected by stroke. Stopping the spread of the infarct area and revitalizing the penumbra is central in stroke research, this new imaging technique may therefore prove to be a valuable tool in the monitoring and developing new treatments.

  10. Perspectives on telemedicine to improve stroke treatment.

    PubMed

    Stewart, S F; Switzer, J A

    2011-02-01

    Stroke is the number three cause of death and the most common cause of adult disability in the United States. Few patients receive the only established effective therapy, intravenous tissue plasminogen activator. Failure to treat may occur due to several reasons, a crucial one being the lack of acute neurologic coverage, particularly in rural settings. In this article we review the difficulties encountered by patients needing immediate care to access stroke specialists. To overcome this delay in patient care, telemedicine technology for acute stroke care is recommended. We track the emergence and evolution of "telestroke" from initial telephone consultation, to point-to-point, hub-and-spoke networks, to web-based site-independent telestroke systems. We detail the emerging evidence for the safety and efficacy of these remote telestroke systems through observational studies (TEMPiS and REACH). Lastly, we discuss areas where telestroke could potentially expand to provide more complete stroke care beyond the acute thrombolysis phase, as well as its potential to improve clinical research and the need for cost-effective research. We conclude that telestroke is currently the most practical solution to any setback faced by stroke specialists with respect to low thrombolytic rates.

  11. Gene-drug interaction in stroke.

    PubMed

    Amici, Serena; Paciaroni, Maurizio; Agnelli, Giancarlo; Caso, Valeria

    2011-01-01

    Stroke is the third cause of mortality and one of most frequent causes of long-term neurological disability, as well as a complex disease that results from the interaction of environmental and genetic factors. The focus on genetics has produced a large number of studies with the objective of revealing the genetic basis of cerebrovascular diseases. Furthermore, pharmacogenetic research has investigated the relation between genetic variability and drug effectiveness/toxicity. This review will examine the implications of pharmacogenetics of stroke; data on antihypertensives, statins, antiplatelets, anticoagulants, and recombinant tissue plasminogen activator will be illustrated. Several polymorphisms have been studied and some have been associated with positive drug-gene interaction on stroke, but the superiority of the genotype-guided approach over the clinical approach has not been proved yet; for this reason, it is not routinely recommended. PMID:22135769

  12. Gene-Drug Interaction in Stroke

    PubMed Central

    Amici, Serena; Paciaroni, Maurizio; Agnelli, Giancarlo; Caso, Valeria

    2011-01-01

    Stroke is the third cause of mortality and one of most frequent causes of long-term neurological disability, as well as a complex disease that results from the interaction of environmental and genetic factors. The focus on genetics has produced a large number of studies with the objective of revealing the genetic basis of cerebrovascular diseases. Furthermore, pharmacogenetic research has investigated the relation between genetic variability and drug effectiveness/toxicity. This review will examine the implications of pharmacogenetics of stroke; data on antihypertensives, statins, antiplatelets, anticoagulants, and recombinant tissue plasminogen activator will be illustrated. Several polymorphisms have been studied and some have been associated with positive drug-gene interaction on stroke, but the superiority of the genotype-guided approach over the clinical approach has not been proved yet; for this reason, it is not routinely recommended. PMID:22135769

  13. Text Detection in Natural Scene Images by Stroke Gabor Words.

    PubMed

    Yi, Chucai; Tian, Yingli

    2011-01-01

    In this paper, we propose a novel algorithm, based on stroke components and descriptive Gabor filters, to detect text regions in natural scene images. Text characters and strings are constructed by stroke components as basic units. Gabor filters are used to describe and analyze the stroke components in text characters or strings. We define a suitability measurement to analyze the confidence of Gabor filters in describing stroke component and the suitability of Gabor filters on an image window. From the training set, we compute a set of Gabor filters that can describe principle stroke components of text by their parameters. Then a K -means algorithm is applied to cluster the descriptive Gabor filters. The clustering centers are defined as Stroke Gabor Words (SGWs) to provide a universal description of stroke components. By suitability evaluation on positive and negative training samples respectively, each SGW generates a pair of characteristic distributions of suitability measurements. On a testing natural scene image, heuristic layout analysis is applied first to extract candidate image windows. Then we compute the principle SGWs for each image window to describe its principle stroke components. Characteristic distributions generated by principle SGWs are used to classify text or nontext windows. Experimental results on benchmark datasets demonstrate that our algorithm can handle complex backgrounds and variant text patterns (font, color, scale, etc.).

  14. Epigenetic Regulation of Oxidative Stress in Ischemic Stroke

    PubMed Central

    Zhao, Haiping; Han, Ziping; Ji, Xunming; Luo, Yumin

    2016-01-01

    The prevalence and incidence of stroke rises with life expectancy. However, except for the use of recombinant tissue-type plasminogen activator, the translation of new therapies for acute stroke from animal models into humans has been relatively unsuccessful. Oxidative DNA and protein damage following stroke is typically associated with cell death. Cause-effect relationships between reactive oxygen species and epigenetic modifications have been established in aging, cancer, acute pancreatitis, and fatty liver disease. In addition, epigenetic regulatory mechanisms during stroke recovery have been reviewed, with focuses mainly on neural apoptosis, necrosis, and neuroplasticity. However, oxidative stress-induced epigenetic regulation in vascular neural networks following stroke has not been sufficiently explored. Improved understanding of the epigenetic regulatory network upon oxidative stress may provide effective antioxidant approaches for treating stroke. In this review, we summarize the epigenetic events, including DNA methylation, histone modification, and microRNAs, that result from oxidative stress following experimental stroke in animal and cell models, and the ways in which epigenetic changes and their crosstalk influence the redox state in neurons, glia, and vascular endothelial cells, helping us to understand the foregone and vicious epigenetic regulation of oxidative stress in the vascular neural network following stroke. PMID:27330844

  15. Adapting the Home After a Stroke

    MedlinePlus

    ... Trials News About Neurology Image Library Search The Internet Stroke Center Patients & Families About Stroke Stroke Diagnosis ... PROFILE→ Credits This section was developed by the Internet Stroke Center and the Program in Occupational Therapy ...

  16. Stroke Survivors Often Struggle with Depression

    MedlinePlus

    ... federal policy. More Health News on: Depression Stroke Stroke Rehabilitation Recent Health News Related MedlinePlus Health Topics Depression Stroke Stroke Rehabilitation About MedlinePlus Site Map FAQs Contact Us Get ...

  17. Neurorestorative therapies for stroke: underlying mechanisms and translation to the clinic

    PubMed Central

    Zhang, Zheng Gang; Chopp, Michael

    2009-01-01

    Restorative cell-based and pharmacological therapies for experimental stroke substantially improve functional outcome. These therapies target several types of parenchymal cells (including neural stem cells, cerebral endothelial cells, astrocytes, oligodendrocytes, and neurons), leading to enhancement of endogenous neurogenesis, angiogenesis, axonal sprouting, and synaptogenesis in the ischaemic brain. Interaction between these restorative events probably underpins the improvement in functional outcome. This Review provides examples of cell-based and pharmacological restorative treatments for stroke that stimulate brain plasticity and functional recovery. The molecular pathways activated by these therapies, which induce remodelling of the injured brain via angiogenesis, neurogenesis, and axonal and dendritic plasticity, are discussed. The ease of treating intact brain tissue to stimulate functional benefit in restorative therapy compared with treating injured brain tissue in neuroprotective therapy might more readily help with translation of restorative therapy from the laboratory to the clinic. PMID:19375666

  18. Melatonin and Ischemic Stroke: Mechanistic Roles and Action

    PubMed Central

    Andrabi, Syed Suhail; Parvez, Suhel; Tabassum, Heena

    2015-01-01

    Stroke is one of the most devastating neurological disabilities and brain's vulnerability towards it proves to be fatal and socio-economic loss of millions of people worldwide. Ischemic stroke remains at the center stage of it, because of its prevalence amongst the several other types attacking the brain. The various cascades of events that have been associated with stroke involve oxidative stress, excitotoxicity, mitochondrial dysfunction, upregulation of Ca2+ level, and so forth. Melatonin is a neurohormone secreted by pineal and extra pineal tissues responsible for various physiological processes like sleep and mood behaviour. Melatonin has been implicated in various neurological diseases because of its antioxidative, antiapoptotic, and anti-inflammatory properties. We have previously reviewed the neuroprotective effect of melatonin in various models of brain injury like traumatic brain injury and spinal cord injury. In this review, we have put together the various causes and consequence of stroke and protective role of melatonin in ischemic stroke. PMID:26435711

  19. Central Nervous System Agents for Ischemic Stroke: Neuroprotection Mechanisms

    PubMed Central

    Pandya, Rachna S.; Mao, Lijuan; Zhou, Hua; Zhou, Shuanhu; Zeng, Jiang; Popp, A. John; Wang, Xin

    2011-01-01

    Stroke is the third leading cause of mortality and disability in the United States. Ischemic stroke constitutes 85% of all stroke cases. However, no effective treatment has been found to prevent damage to the brain in such cases except tissue plasminogen activator with narrow therapeutic window, and there is an unmet need to develop therapeutics for neuroprotection from ischemic stroke. Studies have shown that mechanisms including apoptosis, necrosis, inflammation, immune modulation, and oxidative stress and mediators such as excitatory amino acids, nitric oxide, inflammatory mediators, neurotransmitters, reactive oxygen species, and withdrawal of trophic factors may lead to the development of the ischemic cascade. Hence, it is essential to develop neuroprotective agents targeting either the mechanisms or the mediators leading to development of ischemic stroke. This review focuses on central nervous system agents targeting these biochemical pathways and mediators of ischemic stroke, mainly those that counteract apoptosis, inflammation, and oxidation, and well as glutamate inhibitors which have been shown to provide neuroprotection in experimental animals. All these agents have been shown to improve neurological outcome after ischemic insult in experimental animals in vivo, organotypic brain slice/acute slice ex vivo, and cell cultures in vitro and may therefore aid in preventing long-term morbidity and mortality associated with ischemic stroke. PMID:21521165

  20. [Secondary stroke prevention].

    PubMed

    Ferro, J M; Correia, M; Freire, A; Perez y Sanchez, J; Abrunhosa, M A; Perez y Sanchez, M F

    1998-11-01

    The guidelines for secondary stroke prevention, graded following available scientific evidence, are presented. Stroke and TIA are defined and the indications for referral established. Basic assessment of stroke patients should include laboratory evaluation, ECG, brain CT, ultrasound examination of the extracranial vessels for events in the carotid distribution, and transthoracic or transesophageal echocardiogram if cardioembolism is suspected. The pharmacological and non-pharmacological reduction of blood pressure and serum cholesterol, stopping smoking and reducing alcohol intake are general measures recommended for secondary stroke prevention, together with healthier life-style changes (eating a Mediterranean type diet and performing regular moderate physical exercise). Concerning antithrombotic therapy, oral anticoagulants are recommended for patients with atrial fibrillation and other high to medium emboligenic cardiac risk conditions. Antiplatelet drugs are recommended for all other survivors of an ischemic cerebral event. Aspirin (75-325 mg/day) is the drug of choice. Alternative antiplatelet agents are clopidrogrel, ticlopidine, dipiridamol or triflusal. They can be used in patients with intolerance or contraindication to aspirin or in high-risk subjects. Endarterectomy of the symptomatic carotid is an additional procedure recommended for patients with ischemic stroke or TIA and carotid stenosis > 80% on the side of the symptomatic cerebral hemisphere. PMID:10021804

  1. Education in stroke: strategies to improve stroke patient care.

    PubMed

    Gompertz, Patrick; Slack, Andrew; Vogel, Mira; Burrows, Sharon; Clark, Philippa

    2002-07-01

    'Stroke units save lives', but organized care requires expert staff and regular training to be effective. However, the quality of inpatient care for stroke remains poor, and stroke education is often fragmented between the health-care professions. This review describes some national and local strategies aimed at ensuring that all patients are cared for by expert staff.

  2. Genetic predictors for stroke in children with sickle cell anemia.

    PubMed

    Flanagan, Jonathan M; Frohlich, Denise M; Howard, Thad A; Schultz, William H; Driscoll, Catherine; Nagasubramanian, Ramamoorthy; Mortier, Nicole A; Kimble, Amy C; Aygun, Banu; Adams, Robert J; Helms, Ronald W; Ware, Russell E

    2011-06-16

    Stroke is a devastating complication of sickle cell anemia (SCA), affecting 5% to 10% of patients before adulthood. Several candidate genetic polymorphisms have been proposed to affect stroke risk, but few have been validated, mainly because previous studies were hampered by relatively small sample sizes and the absence of additional patient cohorts for validation testing. To verify the accuracy of proposed genetic modifiers influencing stroke risk in SCA, we performed genotyping for 38 published single nucleotide polymorphisms (SNPs), as well as α-thalassemia, G6PD A(-) variant deficiency, and β-globin haplotype in 2 cohorts of children with well-defined stroke phenotypes (130 stroke, 103 nonstroke). Five polymorphisms had significant influence (P < .05): SNPs in the ANXA2, TGFBR3, and TEK genes were associated with increased stroke risk, whereas α-thalassemia and a SNP in the ADCY9 gene were linked with decreased stroke risk. Further investigation at these genetic regions may help define mutations that confer stroke risk or protection in children with SCA.

  3. Measuring verticality perception after stroke: why and how?

    PubMed

    Pérennou, D; Piscicelli, C; Barbieri, G; Jaeger, M; Marquer, A; Barra, J

    2014-01-01

    About 80 papers dealing with verticality after stroke have been published in the last 20years. Here we reviewed the reasons and findings that explain why measuring verticality perception after stroke is interesting. Research on verticality perception after stroke has contributed to improve the knowledge on brain mechanisms, which build up and update a sense of verticality. Preliminary research using modern techniques of brain imaging has shown that the posterior lateral thalamus and the parietal insular cortex are areas of interest for this internal model of verticality. How they interact and are critical remains to be investigated. From a clinical standpoint, it has now been clearly established that biases in verticality perception are frequent after a stroke, causing postural disorders. Measuring the postural vertical with the wheel paradigm has allowed elucidating the mechanisms of lateropulsion, leading or not to a pushing. Schematically, patients with a hemispheric stroke align their erect posture with an erroneous reference of verticality, tilted to the side opposite the lesion. In patients with a brainstem stroke lateropulsion is usually ipsilesional, and results rather from a pathological asymmetry of tone, through vestibulo-spinal mechanisms. These evolutions of concepts and measurement standards of verticality representation should guide the emergence of rehabilitation programs specifically dedicated to the sense of verticality after stroke. Indeed, several pilot studies using appropriate somatosensory stimulation suggest the possibility to recalibrate the internal model of verticality biased by the stroke, and to improve uprightness. Vestibular stimulations seem to be less relevant and efficient.

  4. Stroke rehabilitation and discharge planning.

    PubMed

    Kerr, Peter

    Nurses play a pivotal role in the rehabilitation and discharge planning process of patients who have had a stroke. The nurse's role in the wider stroke multidisciplinary team is complex and diverse and, as such, stroke nurses may find it hard to describe their role and how it fits into the rehabilitation and discharge planning process. A definition of the stroke nurse role in prominent publications such as those of the Scottish Intercollegiate Guidelines Network and the Royal College of Physicians is lacking. This article emphasises the role of the stroke nurse in the rehabilitation and discharge planning process in the stroke unit, while highlighting the complexity, diversity and importance of this role in providing holistic care and support for patients who have survived a stroke. The author draws on his clinical experience of stroke nursing practice in primary, secondary and tertiary care in west central Scotland.

  5. Performance-based testing in mild stroke: identification of unmet opportunity for occupational therapy.

    PubMed

    Morrison, M Tracy; Edwards, Dorothy F; Giles, Gordon Muir

    2015-01-01

    Age at first stroke is decreasing, and most strokes are mild to moderate in severity. Executive function (EF) deficits are increasingly recognized in the stroke population, but occupational therapists have not altered their evaluation methods to fully accommodate changing patient needs. We present a hierarchical performance-based testing (PBT) pathway using data to illustrate how PBT could identify patients with mild stroke-related EF deficits in need of occupational therapy intervention. Data suggest that a substantial number of patients with EF deficits after mild stroke could benefit from occupational therapy services.

  6. Plotting Lightning-Stroke Data

    NASA Technical Reports Server (NTRS)

    Tatom, F. B.; Garst, R. A.

    1986-01-01

    Data on lightning-stroke locations become easier to correlate with cloudcover maps with aid of new graphical treatment. Geographic region divided by grid into array of cells. Number of lightning strokes in each cell tabulated, and value representing density of lightning strokes assigned to each cell. With contour-plotting routine, computer draws contours of lightning-stroke density for region. Shapes of contours compared directly with shapes of storm cells.

  7. Microwave hemorrhagic stroke detector

    DOEpatents

    Haddad, Waleed S.; Trebes, James E.

    2002-01-01

    The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device is based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stroke in human or animal patients as well as for the detection of hemorrhage within a patient's body.

  8. The Dark Side of the Force – Constraints and Complications of Cell Therapies for Stroke

    PubMed Central

    Boltze, Johannes; Arnold, Antje; Walczak, Piotr; Jolkkonen, Jukka; Cui, Lili; Wagner, Daniel-Christoph

    2015-01-01

    Cell therapies are increasingly recognized as a promising option to augment the limited therapeutic arsenal available to fight ischemic stroke. During the last two decades, cumulating preclinical evidence has indicated a substantial efficacy for most cell treatment paradigms and first clinical trials are currently underway to assess safety and feasibility in patients. However, the strong and still unmet demand for novel stroke treatment options and exciting findings reported from experimental studies may have drawn our attention away from potential side effects related to cell therapies and the ways by which they are commonly applied. This review summarizes common and less frequent adverse events that have been discovered in preclinical and clinical investigations assessing cell therapies for stroke. Such adverse events range from immunological and neoplastic complications over seizures to cell clotting and cell-induced embolism. It also describes potential complications of clinically applicable administration procedures, detrimental interactions between therapeutic cells, and the pathophysiological environment that they are placed into, as well as problems related to cell manufacturing. Virtually each therapeutic intervention comes at a certain risk for complications. Side effects do therefore not generally compromise the value of cell treatments for stroke, but underestimating such complications might severely limit therapeutic safety and efficacy of cell treatment protocols currently under development. On the other hand, a better understanding will provide opportunities to further improve existing therapeutic strategies and might help to define those circumstances, under which an optimal effect can be realized. Hence, the review eventually discusses strategies and recommendations allowing us to prevent or at least balance potential complications in order to ensure the maximum therapeutic benefit at minimum risk for stroke patients. PMID:26257702

  9. Association of dementia with death after ischemic stroke: A two-year prospective study

    PubMed Central

    Gao, Chang-Yue; Lian, Yan; Zhang, Meng; Zhang, Li-Li; Fang, Chuan-Qing; Deng, Juan; Li, Jing; Xu, Zhi-Qiang; Zhou, Hua-Dong; Wang, Yan-Jiang

    2016-01-01

    The association between dementia and the risk of death after ischemic stroke was investigated. Neurological, neuropsychological and functional assessments were evaluated in 619 patients with acute ischemic stroke. Dementia was diagnosed at admission and at three months after stroke onset. The patients were scheduled for a two-year follow-up after the index stroke. The Kaplan-Meier survival and Cox proportional hazards regression analyses were used to estimate the cumulative proportion of survival, and the association between dementia and risk of death after stroke. In total, 146 patients (23.6%) were diagnosed with dementia after stroke. The cumulative proportion of surviving cases was 49.3% in patients with dementia after a median follow-up of 21.2±5.6 months, and 92.5% in patients without dementia. Multivariate analysis revealed that dementia (HR, 7.21; 95% CI, 3.85–13.49) was associated with death, independent of age, atrial fibrillation, previous stroke and NIH stroke scale. In conclusion, the mortality rate is increased in stroke patients with dementia. Dementia is an important risk factor for death after stroke, independent of age, atrial fibrillation, previous stroke, and the severity of the stroke. PMID:27588095

  10. Plasma phospholipid arachidonic acid and lignoceric acid are associated with the risk of cardioembolic stroke.

    PubMed

    Chung, Hye-Kyung; Cho, Yoonsu; Do, Hyun Ju; Oh, Kyungmi; Seo, Woo-Keun; Shin, Min-Jeong

    2015-11-01

    Cardioembolic (CE) stroke is the most severe subtype of ischemic stroke with high recurrence and mortality. However, there is still little information on the association of plasma fatty acid (FA) with CE stroke. The objective of this study was to test the hypothesis whether the composition of plasma phospholipid FA is associated with the risk of CE stroke. The study subjects were collected from the Korea University Stroke Registry. Twenty-one subjects were selected as CE stroke group, and 39 age- and sex-matched subjects with non-CE stroke were selected as controls. Sociodemographic factors, clinical measurements, and plasma phospholipid FA compositions were compared between the groups. Logistic regression was used to obtain estimates of the associations between the relevant FAs and CE stroke. The result showed that the CE stroke group had higher levels of free FA and lower levels of triglycerides before and after adjustment (all P < .05). In the regression analysis, elaidic acid (18:1Tn9) and arachidonic acid (20:4n6) were positively related, but lignoceric acid (24:0) was negatively related to CE stroke in all constructed models (all P < .05). In conclusion, plasma phospholipid FA composition was associated with CE stroke risk in Korean population, with higher proportions of elaidic acid and arachidonic acid and lower proportion of lignoceric acid in CE stroke. PMID:26452419

  11. Angiogenesis-regulating microRNAs and Ischemic Stroke.

    PubMed

    Yin, Ke-Jie; Hamblin, Milton; Chen, Y Eugene

    2015-01-01

    Stroke is a leading cause of death and disability worldwide. Ischemic stroke is the dominant subtype of stroke and results from focal cerebral ischemia due to occlusion of major cerebral arteries. Thus, the restoration or improvement of reduced regional cerebral blood supply in a timely manner is very critical for improving stroke outcomes and poststroke functional recovery. The recovery from ischemic stroke largely relies on appropriate restoration of blood flow via angiogenesis. Newly formed vessels would allow increased cerebral blood flow, thus increasing the amount of oxygen and nutrients delivered to affected brain tissue. Angiogenesis is strictly controlled by many key angiogenic factors in the central nervous system, and these molecules have been well-documented to play an important role in the development of angiogenesis in response to various pathological conditions. Promoting angiogenesis via various approaches that target angiogenic factors appears to be a useful treatment for experimental ischemic stroke. Most recently, microRNAs (miRs) have been identified as negative regulators of gene expression in a post-transcriptional manner. Accumulating studies have demonstrated that miRs are essential determinants of vascular endothelial cell biology/angiogenesis as well as contributors to stroke pathogenesis. In this review, we summarize the knowledge of stroke-associated angiogenic modulators, as well as the role and molecular mechanisms of stroke-associated miRs with a focus on angiogenesis-regulating miRs. Moreover, we further discuss their potential impact on miR-based therapeutics in stroke through targeting and enhancing post-ischemic angiogenesis.

  12. Stroke and Episodic Memory Disorders

    ERIC Educational Resources Information Center

    Lim, Chun; Alexander, Michael P.

    2009-01-01

    Memory impairments are common after stroke, and the anatomical basis for impairments may be quite variable. To determine the range of stroke-related memory impairment, we identified all case reports and group studies through the Medline database and the Science Citation Index. There is no hypothesis about memory that is unique to stroke, but there…

  13. The stroke rehabilitation paradigm.

    PubMed

    Kelly, Brian M; Pangilinan, Percival H; Rodriguez, Gianna M

    2007-11-01

    The matrix of stroke rehabilitation is evolving as we look outside the box of traditional therapy type, timing, and intensity of rehabilitation techniques. For inpatient wards, the goal of medical stability and prompt resolution of complications to maximize participation in therapy remains paramount. In the current medical model, we focus on teaching compensatory strategies and rarely on restorative approaches because of time and financial limitations. Researchers aim to identify new technologic and molecular approaches to improve functional outcomes and more accurately predict disability. This article examines different concepts surrounding the comprehensive rehabilitation paradigm of stroke survivors.

  14. Endocarditis and Stroke

    PubMed Central

    GRECU, Nicolae; TIU, Cristina; TERECOASA, Elena; BAJENARU, Ovidiu

    2014-01-01

    Endocarditis is an important, although less common, cause of cerebral embolism. All forms of endocarditis share an initial common pathophysiologic pathway, best illustrated by the non-bacterial thrombotic form, but also a final potential for embolization. Stroke associated with endocarditis has signifficant mortality and morbidity rates, especially due to the frequent concomitant multiple sites of brain embolization. In this article we aim to briefly review endocarditis with a focus on stroke as a complication, while also presenting case correlates from our department. PMID:25705308

  15. Noninvasive brain-computer interface enables communication after brainstem stroke.

    PubMed

    Sellers, Eric W; Ryan, David B; Hauser, Christopher K

    2014-10-01

    Brain-computer interfaces (BCIs) provide communication that is independent of muscle control, and can be especially important for individuals with severe neuromuscular disease who cannot use standard communication pathways or other assistive technology. It has previously been shown that people with amyotrophic lateral sclerosis (ALS) can successfully use BCI after all other means of independent communication have failed. The BCI literature has asserted that brainstem stroke survivors can also benefit from BCI use. This study used a P300-based event-related potential spelling system. This case study demonstrates that an individual locked-in owing to brainstem stroke was able to use a noninvasive BCI to communicate volitional messages. Over a period of 13 months, the participant was able to successfully operate the system during 40 of 62 recording sessions. He was able to accurately spell words provided by the experimenter and to initiate dialogues with his family. The results broadly suggest that, regardless of the precipitating event, BCI use may be of benefit to those with locked-in syndrome.

  16. Self-Reported Fatigue and Associated Factors Six Years after Stroke.

    PubMed

    Elf, Marie; Eriksson, Gunilla; Johansson, Sverker; von Koch, Lena; Ytterberg, Charlotte

    2016-01-01

    Several studies have found that fatigue is one of the most commonly reported symptoms after stroke and the most difficult to cope with. The present study aimed to investigate the presence and severity of self-reported fatigue six years after stroke onset and associated factors. The cohort "Life After Stroke Phase I" (n = 349 persons) was invited at six years to report fatigue (Fatigue Severity Scale 7-item version), perceived impact of stroke and global recovery after stroke (Stroke Impact Scale), anxiety and depression (Hospital Anxiety and Depression Scale), life satisfaction (Life Satisfaction Checklist) and participation in everyday social activities (Frenchay Activities Index). At six years 37% of the 102 participants in this cross-sectional study reported fatigue. The results showed that in nearly all SIS domains the odds for post-stroke fatigue were higher in persons with a higher perceived impact. Furthermore, the odds for post-stroke fatigue were higher in those who had experienced a moderate/severe stroke and had signs of depression and anxiety. Fatigue is still present in one-third of persons as long as six years after stroke onset and is perceived to hinder many aspects of functioning in everyday life. There is an urgent need to develop and evaluate interventions to reduce fatigue. PMID:27575043

  17. Self-Reported Fatigue and Associated Factors Six Years after Stroke

    PubMed Central

    Eriksson, Gunilla; Johansson, Sverker; von Koch, Lena; Ytterberg, Charlotte

    2016-01-01

    Several studies have found that fatigue is one of the most commonly reported symptoms after stroke and the most difficult to cope with. The present study aimed to investigate the presence and severity of self-reported fatigue six years after stroke onset and associated factors. The cohort “Life After Stroke Phase I” (n = 349 persons) was invited at six years to report fatigue (Fatigue Severity Scale 7-item version), perceived impact of stroke and global recovery after stroke (Stroke Impact Scale), anxiety and depression (Hospital Anxiety and Depression Scale), life satisfaction (Life Satisfaction Checklist) and participation in everyday social activities (Frenchay Activities Index). At six years 37% of the 102 participants in this cross-sectional study reported fatigue. The results showed that in nearly all SIS domains the odds for post-stroke fatigue were higher in persons with a higher perceived impact. Furthermore, the odds for post-stroke fatigue were higher in those who had experienced a moderate/severe stroke and had signs of depression and anxiety. Fatigue is still present in one-third of persons as long as six years after stroke onset and is perceived to hinder many aspects of functioning in everyday life. There is an urgent need to develop and evaluate interventions to reduce fatigue. PMID:27575043

  18. Effects on five species of shorebirds of experimental closure of a beach in New Jersey: implications for severe storms and sea-level rise.

    PubMed

    Burger, Joanna; Niles, Larry

    2014-01-01

    For management, it is important to understand the factors that affect foraging efficiency of birds during migration, especially in the face of severe storms and sea-level rise. An experiment was conducted whereby a beach used extensively by migrant shorebirds and people was open and experimentally closed to human activity to examine factors affecting feeding when there was no disturbance, with the beach opened or closed to human activity, and following disturbances. When the beach was closed, the factors affecting the percent of shorebirds foraging varied by species, but involved the number of conspecifics or other shorebirds, location along the beach, and number of raptors. Overall, 30% of flocks were disturbed as a function of type of disturbance, location along the beach, and whether the beach was open or closed. These data suggest that individuals, vehicles, and raptors influence the ability of shorebirds to forage undisturbed, indicating the importance of having some sections of important stopover beaches where shorebirds can feed and roost undisturbed by human activity. A corollary is that other parts of the beach can be freely used by people; environmental health can encompass both protected areas for shorebirds and open areas for fishing and recreation. Severe storms and sea-level rise will limit beach space for both human and avian activities, and understanding mitigation for both is essential to wise adaptive management.

  19. Neuro-fuzzy computing for vibration-based damage localization and severity estimation in an experimental wind turbine blade with superimposed operational effects

    NASA Astrophysics Data System (ADS)

    Hoell, Simon; Omenzetter, Piotr

    2016-04-01

    Fueled by increasing demand for carbon neutral energy, erections of ever larger wind turbines (WTs), with WT blades (WTBs) with higher flexibilities and lower buckling capacities lead to increasing operation and maintenance costs. This can be counteracted with efficient structural health monitoring (SHM), which allows scheduling maintenance actions according to the structural state and preventing dramatic failures. The present study proposes a novel multi-step approach for vibration-based structural damage localization and severity estimation for application in operating WTs. First, partial autocorrelation coefficients (PACCs) are estimated from vibrational responses. Second, principal component analysis is applied to PACCs from the healthy structure in order to calculate scores. Then, the scores are ranked with respect to their ability to differentiate different damage scenarios. This ranking information is used for constructing hierarchical adaptive neuro-fuzzy inference systems (HANFISs), where cross-validation is used to identify optimal numbers of hierarchy levels. Different HANFISs are created for the purposes of structural damage localization and severity estimation. For demonstrating the applicability of the approach, experimental data are superimposed with signals from numerical simulations to account for characteristics of operational noise. For the physical experiments, a small scale WTB is excited with a domestic fan and damage scenarios are introduced non-destructively by attaching small masses. Numerical simulations are also performed for a representative fully functional small WT operating in turbulent wind. The obtained results are promising for future applications of vibration-based SHM to facilitate improved safety and reliability of WTs at lower costs.

  20. Why are patients with acute stroke admitted to hospital?

    PubMed Central

    Bamford, J; Sandercock, P; Warlow, C; Gray, M

    1986-01-01

    Data on 515 consecutive patients registered with the Oxfordshire Community Stroke Project were used to compare the characteristics of those patients who were admitted to hospital within one month after their first stroke with those who remained in the community during that time. Twenty eight patients had their stroke while in hospital for other conditions, and of the remaining 487, 266 were admitted. Though patients with a severe neurological deficit were significantly more likely to be admitted, 47 out of 202 such patients were managed in the community. In a substudy of 162 consecutive patients the general practitioners' reasons for either arranging admission to hospital or continuing with community care in the first week after the stroke were ascertained. Sixty patients were admitted. The only reason for admission was diagnostic uncertainty in five cases (though this was a contributing factor in 25) and to provide nursing or general, non-medical care in 25. Patients who lived alone were more likely to be admitted. All 12 patients who presented directly to the casualty department were admitted, though only five had had a severe stroke. A stroke service that provides a facility for rapid outpatient and domiciliary diagnosis as well as a rapidly acting domiciliary nursing team might reduce the number of patients with stroke admitted to hospital without adversely affecting the quality of patient care: this should be properly evaluated. PMID:3085852

  1. Sex, Stroke, and Inflammation: The potential for Estrogen-mediated immunoprotection in stroke

    PubMed Central

    Ritzel, Rodney M.; Capozzi, Lori A.; McCullough, Louise D.

    2012-01-01

    Stroke is the third leading cause of death and the primary cause of disability in the developed world. Experimental and clinical data indicate that stroke is a sexually dimorphic disease, with males demonstrating an enhanced intrinsic sensitivity to ischemic damage throughout most of their lifespan. The neuroprotective role of estrogen in the female brain is well established, however, estrogen exposure can also be deleterious, especially in older women. The mechanisms for this remain unclear. Our current understanding is based on studies examining estrogen as it relates to neuronal injury, yet cerebral ischemia also induces a robust sterile inflammatory response involving local and systemic immune cells. Despite the potent anti-inflammatory effects of estrogen, few studies have investigated the contribution of estrogen to sex differences in the inflammatory response to stroke. This review examines the potential role for estrogen-mediated immunoprotection in ischemic injury. PMID:22561337

  2. Effect of a 72 Hour Stroke Care Bundle on Early Outcomes after Acute Stroke: A Non Randomised Controlled Study

    PubMed Central

    Nakibuuka, Jane; Sajatovic, Martha; Nankabirwa, Joaniter; Ssendikadiwa, Charles; Kalema, Nelson; Kwizera, Arthur; Byakika-Tusiime, Jayne; Furlan, Anthony J.; Kayima, James; Ddumba, Edward; Katabira, Elly

    2016-01-01

    Background Integrated care pathways (ICP) in stroke management are increasingly being implemented to improve outcomes of acute stroke patients. We evaluated the effect of implementing a 72 hour stroke care bundle on early outcomes among patients admitted within seven days post stroke to the national referral hospital in Uganda. Methods In a one year non-randomised controlled study, 127 stroke patients who had ‘usual care’ (control group) were compared to 127 stroke patients who received selected elements from an ICP (intervention group). Patients were consecutively enrolled (controls first, intervention group second) into each group over 5 month periods and followed to 30-days post stroke. Incidence outcomes (mortality and functional ability) were compared using chi square test and adjusted for potential confounders. Kaplan Meier survival estimates and log rank test for comparison were used for time to death analysis for all strokes and by stroke severity categories. Secondary outcomes were in-hospital mortality, median survival time and median length of hospital stay. Results Mortality within 7 days was higher in the intervention group compared to controls (RR 13.1, 95% CI 3.3–52.9). There was no difference in 30-day mortality between the two groups (RR 1.2, 95% CI 0.5–2.6). There was better 30-day survival in patients with severe stroke in the intervention group compared to controls (P = 0.018). The median survival time was 30 days (IQR 29–30 days) in the control group and 30 days (IQR 7–30 days) in the intervention group. In the intervention group, 41patients (32.3%) died in hospital compared to 23 (18.1%) in controls (P < 0.001). The median length of hospital stay was 8 days (IQR 5–12 days) in the controls and 4 days (IQR 2–7 days) in the intervention group. There was no difference in functional outcomes between the groups (RR 0.9, 95% CI 0.4–2.2). Conclusions While implementing elements of a stroke-focused ICP in a Ugandan national referral

  3. Astrocyte matricellular proteins that control excitatory synaptogenesis are regulated by inflammatory cytokines and correlate with paralysis severity during experimental autoimmune encephalomyelitis.

    PubMed

    Blakely, Pennelope K; Hussain, Shabbir; Carlin, Lindsey E; Irani, David N

    2015-01-01

    The matricellular proteins, secreted protein acidic and rich in cysteine (SPARC) and SPARC-like 1 (SPARCL1), are produced by astrocytes and control excitatory synaptogenesis in the central nervous system. While SPARCL1 directly promotes excitatory synapse formation in vitro and in the developing nervous system in vivo, SPARC specifically antagonizes the synaptogenic actions of SPARCL1. We hypothesized these proteins also help maintain existing excitatory synapses in adult hosts, and that local inflammation in the spinal cord alters their production in a way that dynamically modulates motor synapses and impacts the severity of paralysis during experimental autoimmune encephalomyelitis (EAE) in mice. Using a spontaneously remitting EAE model, paralysis severity correlated inversely with both expression of synaptic proteins and the number of synapses in direct contact with the perikarya of motor neurons in spinal gray matter. In both remitting and non-remitting EAE models, paralysis severity also correlated inversely with sparcl1:sparc transcript and SPARCL1:SPARC protein ratios directly in lumbar spinal cord tissue. In vitro, astrocyte production of both SPARCL1 and SPARC was regulated by T cell-derived cytokines, causing dynamic modulation of the SPARCL1:SPARC expression ratio. Taken together, these data support a model whereby proinflammatory cytokines inhibit SPARCL1 and/or augment SPARC expression by astrocytes in spinal gray matter that, in turn, cause either transient or sustained synaptic retraction from lumbar spinal motor neurons thereby regulating hind limb paralysis during EAE. Ongoing studies seek ways to alter this SPARCL1:SPARC expression ratio in favor of synapse reformation/maintenance and thus help to modulate neurologic deficits during times of inflammation. This could identify new astrocyte-targeted therapies for diseases such as multiple sclerosis. PMID:26500475

  4. Astrocyte matricellular proteins that control excitatory synaptogenesis are regulated by inflammatory cytokines and correlate with paralysis severity during experimental autoimmune encephalomyelitis.

    PubMed

    Blakely, Pennelope K; Hussain, Shabbir; Carlin, Lindsey E; Irani, David N

    2015-01-01

    The matricellular proteins, secreted protein acidic and rich in cysteine (SPARC) and SPARC-like 1 (SPARCL1), are produced by astrocytes and control excitatory synaptogenesis in the central nervous system. While SPARCL1 directly promotes excitatory synapse formation in vitro and in the developing nervous system in vivo, SPARC specifically antagonizes the synaptogenic actions of SPARCL1. We hypothesized these proteins also help maintain existing excitatory synapses in adult hosts, and that local inflammation in the spinal cord alters their production in a way that dynamically modulates motor synapses and impacts the severity of paralysis during experimental autoimmune encephalomyelitis (EAE) in mice. Using a spontaneously remitting EAE model, paralysis severity correlated inversely with both expression of synaptic proteins and the number of synapses in direct contact with the perikarya of motor neurons in spinal gray matter. In both remitting and non-remitting EAE models, paralysis severity also correlated inversely with sparcl1:sparc transcript and SPARCL1:SPARC protein ratios directly in lumbar spinal cord tissue. In vitro, astrocyte production of both SPARCL1 and SPARC was regulated by T cell-derived cytokines, causing dynamic modulation of the SPARCL1:SPARC expression ratio. Taken together, these data support a model whereby proinflammatory cytokines inhibit SPARCL1 and/or augment SPARC expression by astrocytes in spinal gray matter that, in turn, cause either transient or sustained synaptic retraction from lumbar spinal motor neurons thereby regulating hind limb paralysis during EAE. Ongoing studies seek ways to alter this SPARCL1:SPARC expression ratio in favor of synapse reformation/maintenance and thus help to modulate neurologic deficits during times of inflammation. This could identify new astrocyte-targeted therapies for diseases such as multiple sclerosis.

  5. Catheter-based interventions for acute ischaemic stroke

    PubMed Central

    Widimsky, Petr; Hopkins, L. Nelson

    2016-01-01

    Catheter-based interventions for acute ischaemic stroke currently include clot removal (usually from the medial cerebral artery) with modern stent-retrievers and in one of five patients (who have simultaneous or stand-alone internal carotid occlusion) also extracranial carotid intervention. Several recently published randomized trials clearly demonstrated superiority of catheter-based interventions (with or without bridging thrombolysis) over best medical therapy alone. The healthcare systems should adopt the new strategies for acute stroke treatment (including fast track to interventional lab) to offer the benefits to all suitable acute stroke patients. PMID:26429799

  6. The Importance of Patient Involvement in Stroke Rehabilitation

    PubMed Central

    2016-01-01

    Objective To investigate the perceived needs for health services by persons with stroke within the first year after rehabilitation, and associations between perceived impact of stroke, involvement in decisions regarding care/treatment, and having health services needs met. Method Data was collected, through a mail survey, from patients with stroke who were admitted to a university hospital in 2012 and had received rehabilitation after discharge from the stroke unit. The rehabilitation lasted an average of 2 to 4.6 months. The Stroke Survivor Needs Survey Questionnaire was used to assess the participants' perceptions of involvement in decisions on care or treatment and needs for health services in 11 problem areas: mobility, falls, incontinence, pain, fatigue, emotion, concentration, memory, speaking, reading, and sight. The perceived impact of stroke in eight areas was assessed using the Stroke Impact Scale (SIS) 3.0. Eleven logistic regression models were created to explore associations between having health services needs met in each problem area respectively (dependent variable) and the independent variables. In all models the independent variables were: age, sex, SIS domain corresponding to the dependent variable, or stroke severity in cases when no corresponding SIS domain was identified, and involvement in decisions on care and treatment. Results The 63 participants who returned the questionnaires had a mean age of 72 years, 33 were male and 30 were female. Eighty percent had suffered a mild stroke. The number of participants who reported problems varied between 51 (80%, mobility) and 24 (38%, sight). Involvement in decisions on care and treatment was found to be associated with having health services needs met in six problem areas: falls, fatigue, emotion, memory, speaking, and reading. Conclusions The results highlight the importance of involving patients in making decisions on stroke rehabilitation, as it appears to be associated with meeting their health

  7. Stroke: roles of B vitamins, homocysteine and antioxidants.

    PubMed

    Sánchez-Moreno, Concepción; Jiménez-Escrig, Antonio; Martín, Antonio

    2009-06-01

    In the present review concerning stroke, we evaluate the roles of B vitamins, homocysteine and antioxidant vitamins. Stroke is a leading cause of death in developed countries. However, current therapeutic strategies for stroke have been largely unsuccessful. Several studies have reported important benefits on reducing the risk of stroke and improving the post-stroke-associated functional declines in patients who ate foods rich in micronutrients, including B vitamins and antioxidant vitamins E and C. Folic acid, vitamin B6 and vitamin B12 are all cofactors in homocysteine metabolism. Growing interest has been paid to hyperhomocysteinaemia as a risk factor for CVD. Hyperhomocysteinaemia has been linked to inadequate intake of vitamins, particularly to B-group vitamins and therefore may be amenable to nutritional intervention. Hence, poor dietary intake of folate, vitamin B6 and vitamin B12 are associated with increased risk of stroke. Elevated consumption of fruits and vegetables appears to protect against stroke. Antioxidant nutrients have important roles in cell function and have been implicated in processes associated with ageing, including vascular, inflammatory and neurological damage. Plasma vitamin E and C concentrations may serve as a biological marker of lifestyle or other factors associated with reduced stroke risk and may be useful in identifying those at high risk of stroke. After reviewing the observational and intervention studies, there is an incomplete understanding of mechanisms and some conflicting findings; therefore the available evidence is insufficient to recommend the routine use of B vitamins, vitamin E and vitamin C for the prevention of stroke. A better understanding of mechanisms, along with well-designed controlled clinical trials will allow further progress in this area.

  8. Cryptogenic postpartum stroke.

    PubMed

    Bereczki, Dániel; Szegedi, Norbert; Szakács, Zoltán; Gubucz, István; May, Zsolt

    2016-01-01

    An estimated 25-40% of ischemic strokes are classified as cryptogenic, which means the cause of the cerebral infarction remains unidentified. One of the potential pathomechanisms - especially among young patients with no cardiovascular risk factors - is paradoxical embolism through a patent foramen ovale. Pregnancy, cesarean delivery and the postpartum period are associated with an increased risk of cerebrovascular events. Factors that may contribute to ischemic strokes during gestation and puerperium include classic cardiovascular risk factors, changes in hemostaseology/hemodynamics, and pregnancy-specific disorders such as pre-eclampsia, eclampsia, postpartum cerebral angiopathy or peripartum cardiomyopathy. In this case report, we present a 36-year-old thrombolysis candidate undergoing mechanical thrombectomy 3 weeks after a cesarean section due to HELLP-syndrome. After evaluation of anamnestic and diagnostic parameters, closure of the patent foramen ovale has been performed. In the absence of specific guidelines, diagnostic work-up for cryptogenic stroke should be oriented after the suspected pathomechanism based on patient history and clinical picture. As long as definite evidences emerge, management of cryptogenic stroke patients with pathogenic right-to-left shunt remains individual based on the mutual decision of the patient and the multidisciplinary medical team. PMID:27591063

  9. [Social impact of stroke due to atrial fibrillation].

    PubMed

    Santamarina, E; Alvarez Sabín, J

    2012-03-01

    Atrial fibrillation (AF) is the most frequent heart arrhythmia and causes a substantial proportion of ischemic strokes. AF has a marked impact on stroke severity, as well as on morbidity and mortality in these patients. The importance of AF as an etiologic factor of stroke increases in the elderly and in the last few years its detection has increased. The presence of AF leads to more severe initial neurological involvement, longer hospitalization, greater disability and a lower probability of discharge to home. In addition, AF is an independent risk factor for mortality, especially in women and the elderly. All these factors lead to a higher social and economic impact among stroke patients with AF.

  10. Stroke and pregnancy: an integrative review with implications for neuroscience nurses.

    PubMed

    Beal, Claudia C; Faucher, Mary Ann

    2015-04-01

    Stroke in association with pregnancy is an infrequent occurrence, but there is evidence that the incidence is rising. The physiological changes of pregnancy are thought to increase stroke risk, and several conditions specific to pregnancy further increase risk. The provision of optimal care to pregnant and postpartum women who experience stroke requires awareness of how the physiological changes of pregnancy may affect the course of stroke and nursing actions. This article provides an overview of current knowledge about pregnancy-related stroke including underlying pathophysiology, risk factors unique to pregnancy, and treatment issues when stroke is a complication of pregnancy. Implications for the nursing care of women with pregnancy-related stroke and maternal child considerations are discussed.

  11. Contribution to the description of the absorber rod behavior in severe accident conditions: An experimental investigation of the Ag-Zr phase diagram

    NASA Astrophysics Data System (ADS)

    Decreton, A.; Benigni, P.; Rogez, J.; Mikaelian, G.; Barrachin, M.; Lomello-Tafin, M.; Antion, C.; Janghorban, A.; Fischer, E.

    2015-10-01

    Most pressurized water reactor (PWR) absorber rods are composed of an Ag-In-Cd (SIC) alloy inside a stainless steel (SS) cladding, themselves inserted into a Zircaloy tube. During a severe accident, the SIC alloy which melts at 800 °C does not practically interact with SS. However, the cladding failure results from its internal pressurization and its eutectic interaction with Zircaloy and occurs at temperatures greater than 1200 °C. The subsequent interaction between the SIC melt and the Zircaloy has a strong impact on the quantities of aerosols released into the primary circuit and finally on the iodine chemistry. Accurate knowledge of the Ag-Zr system is a prerequisite to address this issue. Within this concern, our experimental work is focused both on the investigation of the Ag-Zr phase diagram and on the determination of the thermodynamic properties of the intermetallic compounds in the system. Two intermetallic compounds (AgZr and AgZr2) were identified. Ag-Zr cast alloys with a Ag/Zr ratio of 1:1 elaborated using an arc-melting furnace, once annealed, contained only a single phase AgZr. From metallographic observations, it appears that AgZr2 likely forms by the peritectic reaction from liquid and the bcc (βZr) phase. The partial enthalpies of solution of silver and zirconium in aluminum were experimentally determined at 723 °C in order to determine the enthalpies of formation of the intermetallic compounds. For silver solution calorimetry in aluminum bath, our measurements were successful and in agreement with the previous data. Yet, this study shows that liquid aluminum should not be used as a solvent for zirconium below 1000 °C.

  12. Predicting Hemorrhagic Transformation of Acute Ischemic Stroke

    PubMed Central

    Marsh, Elisabeth B.; Llinas, Rafael H.; Schneider, Andrea L.C.; Hillis, Argye E.; Lawrence, Erin; Dziedzic, Peter; Gottesman, Rebecca F.

    2016-01-01

    Abstract Hemorrhagic transformation (HT) increases the morbidity and mortality of ischemic stroke. Anticoagulation is often indicated in patients with atrial fibrillation, low ejection fraction, or mechanical valves who are hospitalized with acute stroke, but increases the risk of HT. Risk quantification would be useful. Prior studies have investigated risk of systemic hemorrhage in anticoagulated patients, but none looked specifically at HT. In our previously published work, age, infarct volume, and estimated glomerular filtration rate (eGFR) significantly predicted HT. We created the hemorrhage risk stratification (HeRS) score based on regression coefficients in multivariable modeling and now determine its validity in a prospectively followed inpatient cohort. A total of 241 consecutive patients presenting to 2 academic stroke centers with acute ischemic stroke and an indication for anticoagulation over a 2.75-year period were included. Neuroimaging was evaluated for infarct volume and HT. Hemorrhages were classified as symptomatic versus asymptomatic, and by severity. HeRS scores were calculated for each patient and compared to actual hemorrhage status using receiver operating curve analysis. Area under the curve (AUC) comparing predicted odds of hemorrhage (HeRS score) to actual hemorrhage status was 0.701. Serum glucose (P < 0.001), white blood cell count (P < 0.001), and warfarin use prior to admission (P = 0.002) were also associated with HT in the validation cohort. With these variables, AUC improved to 0.854. Anticoagulation did not significantly increase HT; but with higher intensity anticoagulation, hemorrhages were more likely to be symptomatic and more severe. The HeRS score is a valid predictor of HT in patients with ischemic stroke and indication for anticoagulation. PMID:26765425

  13. Improved ethanol yield and reduced Minimum Ethanol Selling Price (MESP) by modifying low severity dilute acid pretreatment with deacetylation and mechanical refining: 1) Experimental

    PubMed Central

    2012-01-01

    Background Historically, acid pretreatment technology for the production of bio-ethanol from corn stover has required severe conditions to overcome biomass recalcitrance. However, the high usage of acid and steam at severe pretreatment conditions hinders the economic feasibility of the ethanol production from biomass. In addition, the amount of acetate and furfural produced during harsh pretreatment is in the range that strongly inhibits cell growth and impedes ethanol fermentation. The current work addresses these issues through pretreatment with lower acid concentrations and temperatures incorporated with deacetylation and mechanical refining. Results The results showed that deacetylation with 0.1 M NaOH before acid pretreatment improved the monomeric xylose yield in pretreatment by up to 20% while keeping the furfural yield under 2%. Deacetylation also improved the glucose yield by 10% and the xylose yield by 20% during low solids enzymatic hydrolysis. Mechanical refining using a PFI mill further improved sugar yields during both low- and high-solids enzymatic hydrolysis. Mechanical refining also allowed enzyme loadings to be reduced while maintaining high yields. Deacetylation and mechanical refining are shown to assist in achieving 90% cellulose yield in high-solids (20%) enzymatic hydrolysis. When fermentations were performed under pH control to evaluate the effect of deacetylation and mechanical refining on the ethanol yields, glucose and xylose utilizations over 90% and ethanol yields over 90% were achieved. Overall ethanol yields were calculated based on experimental results for the base case and modified cases. One modified case that integrated deacetylation, mechanical refining, and washing was estimated to produce 88 gallons of ethanol per ton of biomass. Conclusion The current work developed a novel bio-ethanol process that features pretreatment with lower acid concentrations and temperatures incorporated with deacetylation and mechanical refining. The

  14. Etiologic Ischemic Stroke Phenotypes in the NINDS Stroke Genetics Network

    PubMed Central

    Ay, Hakan; Arsava, Ethem Murat; Andsberg, Gunnar; Benner, Thomas; Brown, Robert D.; Chapman, Sherita N.; Cole, John W.; Delavaran, Hossein; Dichgans, Martin; Engström, Gunnar; Giralt-Steinhauer, Eva; Grewal, Raji P.; Gwinn, Katrina; Jern, Christina; Jimenez-Conde, Jordi; Jood, Katarina; Katsnelson, Michael; Kissela, Brett; Kittner, Steven J.; Kleindorfer, Dawn O.; Labovitz, Daniel L.; Lanfranconi, Silvia; Lee, Jin-Moo; Lehm, Manuel; Lemmens, Robin; Levi, Chris; Li, Linxin; Lindgren, Arne; Markus, Hugh S.; McArdle, Patrick F.; Melander, Olle; Norrving, Bo; Peddareddygari, Leema Reddy; Pedersén, Annie; Pera, Joanna; Rannikmäe, Kristiina; Rexrode, Kathryn M.; Rhodes, David; Rich, Stephen S.; Roquer, Jaume; Rosand, Jonathan; Rothwell, Peter M.; Rundek, Tatjana; Sacco, Ralph L.; Schmidt, Reinhold; Schürks, Markus; Seiler, Stephan; Sharma, Pankaj; Slowik, Agnieszka; Sudlow, Cathie; Thijs, Vincent; Woodfield, Rebecca; Worrall, Bradford B.; Meschia, James F.

    2014-01-01

    Background and Purpose NINDS Stroke Genetics Network (SiGN) is an international consortium of ischemic stroke studies that aims to generate high quality phenotype data to identify the genetic basis of etiologic stroke subtypes. This analysis characterizes the etiopathogenetic basis of ischemic stroke and reliability of stroke classification in the consortium. Methods Fifty-two trained and certified adjudicators determined both phenotypic (abnormal test findings categorized in major etiologic groups without weighting towards the most likely cause) and causative ischemic stroke subtypes in 16,954 subjects with imaging-confirmed ischemic stroke from 12 US studies and 11 studies from 8 European countries using the web-based Causative Classification of Stroke System. Classification reliability was assessed with blinded re-adjudication of 1509 randomly selected cases. Results The distribution of etiologic categories varied by study, age, sex, and race (p<0.001 for each). Overall, only 40% to 54% of cases with a given major ischemic stroke etiology (phenotypic subtype) were classified into the same final causative category with high confidence. There was good agreement for both causative (kappa 0.72, 95%CI:0.69-0.75) and phenotypic classifications (kappa 0.73, 95%CI:0.70-0.75). Conclusions This study demonstrates that etiologic subtypes can be determined with good reliability in studies that include investigators with different expertise and background, institutions with different stroke evaluation protocols and geographic location, and patient populations with different epidemiological characteristics. The discordance between phenotypic and causative stroke subtypes highlights the fact that the presence of an abnormality in a stroke patient does not necessarily mean that it is the cause of stroke. PMID:25378430

  15. Modeling and simulation of the main metabolism in Escherichia coli and its several single-gene knockout mutants with experimental verification

    PubMed Central

    2010-01-01

    Background It is quite important to simulate the metabolic changes of a cell in response to the change in culture environment and/or specific gene knockouts particularly for the purpose of application in industry. If this could be done, the cell design can be made without conducting exhaustive experiments, and one can screen out the promising candidates, proceeded by experimental verification of a select few of particular interest. Although several models have so far been proposed, most of them focus on the specific metabolic pathways. It is preferred to model the whole of the main metabolic pathways in Escherichia coli, allowing for the estimation of energy generation and cell synthesis, based on intracellular fluxes and that may be used to characterize phenotypic growth. Results In the present study, we considered the simulation of the main metabolic pathways such as glycolysis, TCA cycle, pentose phosphate (PP) pathway, and the anapleorotic pathways using enzymatic reaction models of E. coli. Once intracellular fluxes were computed by this model, the specific ATP production rate, the specific CO2 production rate, and the specific NADPH production rate could be estimated. The specific ATP production rate thus computed was used for the estimation of the specific growth rate. The CO2 production rate could be used to estimate cell yield, and the specific NADPH production rate could be used to determine the flux of the oxidative PP pathway. The batch and continuous cultivations were simulated where the changing patterns of extracellular and intra-cellular metabolite concentrations were compared with experimental data. Moreover, the effects of the knockout of such pathways as Ppc, Pck and Pyk on the metabolism were simulated. It was shown to be difficult for the cell to grow in Ppc mutant due to low concentration of OAA, while Pck mutant does not necessarily show this phenomenon. The slower growth rate of the Ppc mutant was properly estimated by taking into account

  16. Embolic Stroke in Cardiomyopathy: Should Patients be Anticoagulated?

    PubMed

    Narang, Akhil; Lang, Roberto M

    2016-05-01

    Despite advances in the treatment of patients with heart failure, mortality is still substantial. Part of this mortality is explained by cardioembolic stroke. Patients with heart failure are predisposed to developing cardioembolic strokes owing to abnormalities in Virchow's triad (endothelial function, relative hypercoagulable state, and static blood flow). Several randomized controlled trials have addressed whether patients with heart failure benefit from anticoagulation. Overall, the results suggest the risk of bleeding with anticoagulation outweighs any small benefit conferred by anticoagulation. PMID:27150169

  17. Ethnic Differences in Post-Stroke Quality of Life in the Brain Attack Surveillance in Corpus Christi (BASIC) Project

    PubMed Central

    Reeves, Sarah L; Brown, Devin L; Baek, Jonggyu; Wing, Jeffrey J; Morgenstern, Lewis B; Lisabeth, Lynda D

    2015-01-01

    Background and Purpose Mexican Americans (MAs) have an increased risk of stroke and experience worse post-stroke disability than non-Hispanic whites (NHWs), which may translate into worse post-stroke quality of life (QOL). We assessed ethnic differences in post-stroke QOL, as well as potential modification of associations by age, sex, and initial stroke severity. Methods Ischemic stroke survivors were identified through the biethnic, population-based Brain Attack Surveillance in Corpus Christi (BASIC) Project. Data were collected from medical records, baseline interviews, and 90-day post-stroke interviews. Post-stroke QOL was measured at approximately 90 days by the validated short-form stroke-specific QOL in 3 domains: overall, physical, and psychosocial (range 0–5; higher scores represent better QOL). Tobit regression was used to model associations between ethnicity and post-stroke QOL scores, adjusted for demographics, clinical characteristics, and pre-stroke cognition and function. Results Among 290 eligible stroke survivors (66% MA, 34% NHW, median age=69 years), median scores for overall, physical, and psychosocial post-stroke QOL were 3.3, 3.8 and 2.7, respectively. Overall post-stroke QOL was lower for MAs than NHWs (mean difference = −0.30, 95%CI:−0.59,−0.01) and in the physical domain (mean difference = −0.47, 95%CI:−0.81,−0.14) after multivariable adjustment. No ethnic difference was found in the psychosocial domain. Age modified the associations between ethnicity and post-stroke QOL such that differences were present in older but not younger ages. Conclusions Disparities exist in post-stroke QOL for MAs and appear to be driven by differences in older stroke patients. Targeted interventions to improve outcomes among MA stroke survivors are urgently needed. PMID:26286542

  18. The influence of gender and age on disability following ischemic stroke: the Framingham study.

    PubMed

    Kelly-Hayes, Margaret; Beiser, Alexa; Kase, Carlos S; Scaramucci, Amy; D'Agostino, Ralph B; Wolf, Philip A

    2003-01-01

    The magnitude of disability among elderly stroke survivors is substantial. There have been few community-based estimates of the contribution gender and older age make to stroke-related disability and outcome. Using the original Framingham Study cohort, we documented gender-specific neurological deficits and disability differences in stroke survivors at six months post-stroke. Logistic regression analyses were performed to estimate odds ratios, comparing men and women, and adjusting for age, and age and stroke subtype. Age and gender-matched controls were then compared to distinguish stroke-related disability from disability associated with general aging. Results showed that almost half (43%) of all elderly stroke survivors in the cohort had moderate to severe neurological deficits. In the crude analyses, women were more dependent in ADLs (33.9% vs 15.6%), less likely to walk unassisted (40.3% vs 17.8%), and living in nursing homes (34.9 % vs 13.3%). After adjusting for age and stroke subtype, it was older age that accounted for the severity of disability. When compared to age and gender-matched controls, stroke cases were significantly more disabled in all domains studied. In this elderly cohort, more women experienced initial strokes and were more disabled at 6 months post-stroke than men. However, older age at stroke onset, not gender or stroke subtype, was associated with greater disability. Health care providers need to understand that strokes occur later in life for women and that because of age, women are at greater risk for disability and institutionalization.

  19. Increased levels of brain serotonin correlated with MMP-9 activity and IL-4 levels resulted in severe experimental autoimmune encephalomyelitis (EAE) in obese mice.

    PubMed

    Hasan, M; Seo, J-E; Rahaman, K A; Kang, M-J; Jung, B-H; Kwon, O-S

    2016-04-01

    The aim of this study was to investigate the role of monoamine neurotransmitters on the severity of experimental autoimmune encephalomyelitis (EAE) in obese mice. EAE was induced in mice with normal diets (ND-EAE) and obese mice with high-fat diets (HFD-EAE) through the immune response to myelin oligodendrocyte glycoprotein (MOG) (35-55). The levels of dopamine (DA), serotonin (5-HT) and their metabolites in different anatomical brain regions were measured by high-performance liquid chromatography. The plasma and tissue NADPH oxidase and matrix metalloproteinases (MMP)-9 activities were analyzed by fluorescence spectrophotometry. The cumulative disease index and disease peaks were significantly higher in HFD-EAE compared with those in ND-EAE. Significantly higher 5-HT levels and lower 5-HT turnovers 5-hydroxyindole acetic acid ((5-HIAA)/5-HT) were found in the brains of HFD-EAE mice compared with those found in the HFD-CON and ND-EAE mice brains. Moreover, increased DA levels were observed in the caudate nucleus of the HFD-EAE mice compared with the control and ND-EAE mice. The NADPH oxidase and MMP-9 activities in the plasma and tissues were significantly higher in both the ND-EAE and HFD-EAE groups than in their respective controls. The cytokine levels in the plasma, tissues, and cultured splenocytes were found to be significantly altered in EAE mice compared with control mice. Moreover, HFD-EAE mice exhibited significantly higher MMP-9 activity and lower IL-4 levels than ND-EAE mice and were significantly correlated with brain 5-HT levels. In conclusion, the increased 5-HT levels in the brain significantly correlated with MMP-9 activity and IL-4 levels play an important role in the exacerbation of disease severity in HFD-EAE mice. PMID:26820599

  20. The mirror neuron system in post-stroke rehabilitation

    PubMed Central

    2013-01-01

    Different treatments for stroke patients have been proposed; among them the mirror therapy and motion imagery lead to functional recovery by providing a cortical reorganization. Up today the basic concepts of the current literature on mirror neurons and the major findings regarding the use of mirror therapy and motor imagery as potential tools to promote reorganization and functional recovery in post-stroke patients. Bibliographic research was conducted based on publications over the past thirteen years written in English in the databases Scielo, Pubmed/MEDLINE, ISI Web of Knowledge. The studies showed how the interaction among vision, proprioception and motor commands promotes the recruitment of mirror neurons, thus providing cortical reorganization and functional recovery of post-stroke patients. We conclude that the experimental advances on Mirror Neurons will bring new rational therapeutic approaches to post-stroke rehabilitation. PMID:24134862

  1. The mirror neuron system in post-stroke rehabilitation.

    PubMed

    Carvalho, Diana; Teixeira, Silmar; Lucas, Marina; Yuan, Ti-Fei; Chaves, Fernanda; Peressutti, Caroline; Machado, Sergio; Bittencourt, Juliana; Menéndez-González, Manuel; Nardi, Antonio Egidio; Velasques, Bruna; Cagy, Mauricio; Piedade, Roberto; Ribeiro, Pedro; Arias-Carrión, Oscar

    2013-01-01

    Different treatments for stroke patients have been proposed; among them the mirror therapy and motion imagery lead to functional recovery by providing a cortical reorganization. Up today the basic concepts of the current literature on mirror neurons and the major findings regarding the use of mirror therapy and motor imagery as potential tools to promote reorganization and functional recovery in post-stroke patients. Bibliographic research was conducted based on publications over the past thirteen years written in English in the databases Scielo, Pubmed/MEDLINE, ISI Web of Knowledge. The studies showed how the interaction among vision, proprioception and motor commands promotes the recruitment of mirror neurons, thus providing cortical reorganization and functional recovery of post-stroke patients. We conclude that the experimental advances on Mirror Neurons will bring new rational therapeutic approaches to post-stroke rehabilitation.

  2. More outcomes than trials: a call for consistent data collection across stroke rehabilitation trials.

    PubMed

    Ali, M; English, C; Bernhardt, J; Sunnerhagen, K S; Brady, M

    2013-01-01

    Stroke survivors experience complex combinations of impairments, activity limitations, and participation restrictions. The essential components of stroke rehabilitation remain elusive. Determining efficacy in randomized controlled trials (RCTs) is challenging; there is no commonly agreed primary outcome measure for rehabilitation trials. Clinical guidelines depend on proof of efficacy in RCTs and meta-analyses. However, diverse trial aims, differing methods, inconsistent data collection, and use of multiple assessment tools hinder comparability across trials. Consistent data collection in acute stroke trials has facilitated meta-analyses to inform trial design and clinical practice. With few exceptions, inconsistent data collection has hindered similar progress in stroke rehabilitation research. There is an urgent need for the routine collection of a core dataset of common variables in rehabilitation trials. The European Stroke Organisation Outcomes Working Group, the National Institutes of Neurological Disorders and Stroke Common Data Elements project, and the Collaborative Stroke Audit and Research project have called for consistency in data collection in stroke trials. Standardizing data collection can decrease study start up times, facilitate data sharing, and inform clinical guidelines. Although achieving consensus on which outcome measures to use in stroke rehabilitation trials is a considerable task, perhaps a feasible starting point is to achieve consistency in the collection of data on demography, stroke severity, and stroke onset to inclusion times. Longer term goals could include the development of a consensus process to establish the core dataset. This should be endorsed by researchers, funders, and journal editors in order to facilitate sustainable change.

  3. Hyperacute management of ischemic stroke.

    PubMed

    Song, Sarah

    2013-11-01

    Stroke is a devastating disease and currently the fourth leading cause of death in this country. Acute ischemic stroke is an emergency and requires effective triage, diagnosis, and critical management. The hyperacute management of ischemic stroke begins in the field, with recognition of stroke symptoms by emergency medical systems (EMS) personnel. The EMS is an important component to an effective stroke system of care, which also includes primary stroke centers, routing protocols for acute ischemic stroke, and telemedicine. Following the arrival of a potential stroke patient to the emergency room setting, patients should be stabilized and undergo assessment for potential intravenous alteplase (IV tPA) treatment. Assessments include diagnostic tests, neuroimaging, and standardized stroke evaluations. After these assessments have been performed, IV tPA, the only medication for acute stroke approved by the U.S. Food and Drug Administration, can be considered using a variety of inclusion and exclusion criteria. Previously time restrictions limited the usage of IV tPA to 3 hours, but this time window has now been extended for eligible candidates to 4.5 hours. The administration of IV tPA has specific requirements for monitoring and should be standardized via protocol across hospitals.

  4. Ischemic Stroke after Heart Transplantation

    PubMed Central

    Acampa, Maurizio; Lazzerini, Pietro Enea; Guideri, Francesca; Tassi, Rossana; Martini, Giuseppe

    2016-01-01

    Cerebrovascular complications after orthotopic heart transplantation (OHT) are more common in comparison with neurological sequelae subsequent to routine cardiac surgery. Ischemic stroke and transient ischemic attack (TIA) are more common (with an incidence of up to 13%) than intracranial hemorrhage (2.5%). Clinically, ischemic stroke is manifested by the appearance of focal neurologic deficits, although sometimes a stroke may be silent or manifests itself by the appearance of encephalopathy, reflecting a diffuse brain disorder. Ischemic stroke subtypes distribution in perioperative and postoperative period after OHT is very different from classical distribution, with different pathogenic mechanisms. Infact, ischemic stroke may be caused by less common and unusual mechanisms, linked to surgical procedures and to postoperative inflammation, peculiar to this group of patients. However, many strokes (40%) occur without a well-defined etiology (cryptogenic strokes). A silent atrial fibrillation (AF) may play a role in pathogenesis of these strokes and P wave dispersion may represent a predictor of AF. In OHT patients, P wave dispersion correlates with homocysteine plasma levels and hyperhomocysteinemia could play a role in the pathogenesis of these strokes with multiple mechanisms increasing the risk of AF. In conclusion, stroke after heart transplantation represents a complication with considerable impact not only on mortality but also on subsequent poor functional outcome. PMID:26915504

  5. Stroke symptoms with absence of recognized stroke are associated with cognitive impairment and depressive symptoms in older adults with diabetes

    PubMed Central

    Passler, Jesse S.; Clay, Olivio J.; Wadley, Virginia G.; Ovalle, Fernando; Crowe, Michael

    2016-01-01

    Self-reported stroke symptoms may represent unrecognized cerebrovascular events leading to poorer cognitive and mental health. We examined relationships between stroke symptoms, cognitive impairment, and depressive symptoms in a high-risk sample: 247 adults age ≥65 with diabetes. Stroke symptoms were assessed using the Questionnaire for Verifying Stroke-free Status, cognitive impairment was measured with the modified Telephone Interview for Cognitive Status, and depressive symptoms were measured using the 15-item Geriatric Depression Scale. In 206 participants without history of stroke/TIA, 27.7% reported stroke symptoms, with sudden loss of comprehension most frequently reported (11.7%). Having >1 vs. 0 stroke symptoms was associated with greater odds of cognitive impairment (OR=3.04, 95% CI, 1.15–8.05) and more depressive symptoms (b =2.60, p<.001) while controlling for age, race, gender, education, diabetes duration, diabetes severity, and cardiovascular comorbidities. Better recognition and treatment of cerebrovascular problems in older adults with diabetes may lead to improved cognition and mental health. PMID:26801916

  6. Stroke Symptoms With Absence of Recognized Stroke Are Associated With Cognitive Impairment and Depressive Symptoms in Older Adults With Diabetes.

    PubMed

    Passler, Jesse S; Clay, Olivio J; Wadley, Virginia G; Ovalle, Fernando; Crowe, Michael

    2016-05-01

    Self-reported stroke symptoms may represent unrecognized cerebrovascular events leading to poorer cognitive and mental health. We examined relationships between stroke symptoms, cognitive impairment, and depressive symptoms in a high-risk sample: 247 adults aged ≥65 with diabetes. Stroke symptoms were assessed using the Questionnaire for Verifying Stroke-free Status, cognitive impairment was measured with the modified Telephone Interview for Cognitive Status, and depressive symptoms were measured using the 15-item Geriatric Depression Scale. In 206 participants without history of stroke/transient ischemic attack, 27.7% reported stroke symptoms, with sudden loss of comprehension most frequently reported (11.7%). Having >1 versus 0 stroke symptoms was associated with greater odds of cognitive impairment (odds ratio = 3.04, 95% confidence interval 1.15-8.05) and more depressive symptoms (b= 2.60,P< .001) while controlling for age, race, gender, education, diabetes duration, diabetes severity, and cardiovascular comorbidities. Better recognition and treatment of cerebrovascular problems in older adults with diabetes may lead to improved cognition and mental health.

  7. Microwave hemorrhagic stroke detector

    DOEpatents

    Haddad, Waleed S.; Trebes, James E.

    2007-06-05

    The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device is based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stoke in human or animal patients as well as for the detection of hemorrhage within a patient's body.

  8. The Influence of Acute Hyperglycemia in an Animal Model of Lacunar Stroke That Is Induced by Artificial Particle Embolization

    PubMed Central

    Tsai, Ming-Jun; Lin, Ming-Wei; Huang, Yaw-Bin; Kuo, Yu-Min; Tsai, Yi-Hung

    2016-01-01

    Animal and clinical studies have revealed that hyperglycemia during ischemic stroke increases the stroke's severity and the infarct size in clinical and animal studies. However, no conclusive evidence demonstrates that acute hyperglycemia worsens post-stroke outcomes and increases infarct size in lacunar stroke. In this study, we developed a rat model of lacunar stroke that was induced via the injection of artificial embolic particles during full consciousness. We then used this model to compare the acute influence of hyperglycemia in lacunar stroke and diffuse infarction, by evaluating neurologic behavior and the rate, size, and location of the infarction. The time course of the neurologic deficits was clearly recorded from immediately after induction to 24 h post-stroke in both types of stroke. We found that acute hyperglycemia aggravated the neurologic deficit in diffuse infarction at 24 h after stroke, and also aggravated the cerebral infarct. Furthermore, the infarct volumes of the basal ganglion, thalamus, hippocampus, and cerebellum but not the cortex were positively correlated with serum glucose levels. In contrast, acute hyperglycemia reduced the infarct volume and neurologic symptoms in lacunar stroke within 4 min after stroke induction, and this effect persisted for up to 24 h post-stroke. In conclusion, acute hyperglycemia aggravated the neurologic outcomes in diffuse infarction, although it significantly reduced the size of the cerebral infarct and improved the neurologic deficits in lacunar stroke. PMID:27226775

  9. Danger signals in stroke.

    PubMed

    Gelderblom, Mathias; Sobey, Christopher G; Kleinschnitz, Christoph; Magnus, Tim

    2015-11-01

    Danger molecules are the first signals released from dying tissue after stroke. These danger signals bind to receptors on immune cells that will result in their activation and the release of inflammatory and neurotoxic mediators, resulting in amplification of the immune response and subsequent enlargement of the damaged brain volume. The release of danger signals is a central event that leads to a multitude of signals and cascades in the affected and neighbouring tissue, therefore providing a potential target for therapy.

  10. The Secondary Prevention of Small Subcortical Strokes (SPS3) study

    PubMed Central

    Benavente, Oscar R.; White, Carole L.; Pearce, Lesly; Pergola, Pablo; Roldan, Ana; Benavente, Marie-France; Coffey, Christopher; McClure, Leslie A.; Szychowski, Jeff M.; Conwit, Robin; Heberling, Patricia A.; Howard, George; Bazan, Carlos; Vidal-Pergola, Gabriela; Talbert, Robert; Hart, Robert G.

    2014-01-01

    Background Small subcortical strokes, also known as lacunar strokes, comprise more than 25% of brain infarcts, and the underlying vasculopathy is the most common cause of vascular cognitive impairment. How to optimally prevent stroke recurrence and cognitive decline in S3 patients is unclear. The aim of the Secondary Prevention of Small Subcortical Strokes study (Trial registration: NCT00059306) is to define strategies for reducing stroke recurrence, cognitive decline, and major vascular events. Methods Secondary Prevention of Small Subcortical Strokes is a randomised, multicentre clinical trial (n = 3000) being conducted in seven countries, and sponsored by the US NINDS/NIH. Patients with symptomatic small subcortical strokes in the six-months before and an eligible lesion on magnetic resonance imaging are simultaneously randomised, in a 2 × 2 factorial design, to antiplatelet therapy – 325 mg aspirin daily plus 75 mg clopidogrel daily, vs. 325 mg aspirin daily plus placebo, double-blind – and to one of two levels of systolic blood pressure targets –‘intensive’ (<130 mmHg) vs. ‘usual’ (130–149 mmHg). Participants are followed for an average of four-years. Time to recurrent stroke (ischaemic or haemorrhagic) is the primary outcome and will be analysed separately for each intervention. The secondary outcomes are the rate of cognitive decline and major vascular events. The primary and most secondary outcomes are adjudicated centrally by those unaware of treatment assignment. Conclusions Secondary Prevention of Small Subcortical Strokes will address several important clinical and scientific questions by testing two interventions in patients with recent magnetic resonance imaging-defined lacunar infarcts, which are likely due to small vessel disease. The results will inform the management of millions of patients with this common vascular disorder. PMID:21371282

  11. NADPH Oxidase as a Therapeutic Target for Neuroprotection against Ischaemic Stroke: Future Perspectives.

    PubMed

    McCann, Sarah K; Roulston, Carli L

    2013-01-01

    Oxidative stress caused by an excess of reactive oxygen species (ROS) is known to contribute to stroke injury, particularly during reperfusion, and antioxidants targeting this process have resulted in improved outcomes experimentally. Unfortunately these improvements have not been successfully translated to the clinical setting. Targeting the source of oxidative stress may provide a superior therapeutic approach. The NADPH oxidases are a family of enzymes dedicated solely to ROS production and pre-clinical animal studies targeting NADPH oxidases have shown promising results. However there are multiple factors that need to be considered for future drug development: There are several homologues of the catalytic subunit of NADPH oxidase. All have differing physiological roles and may contribute differentially to oxidative damage after stroke. Additionally, the role of ROS in brain repair is largely unexplored, which should be taken into consideration when developing drugs that inhibit specific NADPH oxidases after injury. This article focuses on the current knowledge regarding NADPH oxidase after stroke including in vivo genetic and inhibitor studies. The caution required when interpreting reports of positive outcomes after NADPH oxidase inhibition is also discussed, as effects on long term recovery are yet to be investigated and are likely to affect successful clinical translation. PMID:24961415

  12. Is hyperglycaemia an independent predictor of poor outcome after acute stroke? Results of a long-term follow up study.

    PubMed Central

    Weir, C. J.; Murray, G. D.; Dyker, A. G.; Lees, K. R.

    1997-01-01

    OBJECTIVE: To determine whether raised plasma glucose concentration independently influences outcome after acute stroke or is a stress response reflecting increased stroke severity. DESIGN: Long-term follow up study of patients admitted to an acute stroke unit. SETTING: Western Infirmary, Glasgow. SUBJECTS: 811 patients with acute stroke confirmed by computed tomography. Analysis was restricted to the 750 non-diabetic patients. MAIN OUTCOME MEASURES: Survival time and placement three months after stroke. RESULTS: 645 patients (86%) had ischaemic stroke and 105 patients (14%) haemorrhagic stroke. Cox's proportional hazards modelling with stratification according to Oxfordshire Community Stroke Project categories identified increased age (relative hazard 1.36 per decade; 95% confidence interval 1.21 to 1.53), haemorrhagic stroke (relative hazard 1.67; 1.22 to 2.28), time to resolution of symptoms > 72 hours (relative hazard 2.15; 1.15 to 4.05), and hyperglycaemia (relative hazard 1.87; 1.43 to 2.45) as predictors of mortality. The effect of glucose concentration on survival was greatest in the first month. CONCLUSIONS: Plasma glucose concentration above 8 mmol/l after acute stroke predicts a poor prognosis after correcting for age, stroke severity, and stroke subtype. Raised plasma glucose concentration is therefore unlikely to be solely a stress response and should arguably be treated actively. A randomised trial is warranted. PMID:9158464

  13. Connector Mechanism Has Smaller Stroke

    NASA Technical Reports Server (NTRS)

    Milam, M. Bruce

    1992-01-01

    System for connecting electrical and/or fluid lines includes mechanism reducing length of stroke necessary to make or break connections. Feature enables connection and disconnection in confined space, and compensates for misalignment between connectors. Connector in active member moves upward at twice the speed of downward stroke of passive member. Stroke amplified within connector system. Applications include connections between modular electronic units, coupled vehicles, and hydraulic systems.

  14. Impact of Diabetes on Stroke Risk and Outcomes: Two Nationwide Retrospective Cohort Studies.

    PubMed

    Liao, Chien-Chang; Shih, Chun-Chuan; Yeh, Chun-Chieh; Chang, Yi-Cheng; Hu, Chaur-Jong; Lin, Jaung-Geng; Chen, Ta-Liang

    2015-12-01

    Several limitations existed in previous studies which suggested that diabetic patients have increased risk of stroke. We conducted this study to better understand the stroke risk and poststroke outcomes in patients with diabetes.From the claims data of Taiwan's National Health Insurance, we identified 24,027 adults with new-diagnosed diabetes and 96,108 adults without diabetes between 2000 and 2003 in a retrospective cohort study. Stroke events (included hemorrhage, ischemia, and other type of stroke) during the follow-up period of 2000 to 2008 were ascertained and adjusted risk of stroke associated with diabetes was calculated. A nested cohort study of 221,254 hospitalized stroke patients (included hemorrhage, ischemia, and other type of stroke) between 2000 and 2009 was conducted. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for adverse events after stroke hospitalization in patients with and without diabetes.The incidences of stroke in cohorts with and without diabetes were 10.1 and 4.5 per 1000 person-years, respectively. During the follow-up period, diabetic patients had an increased risk of stroke (adjusted hazard ratio: 1.75; 95% CI: 1.64-1.86) than those without diabetes. Associations between diabetes and stroke risk were significant in both sexes and all age groups. Previous diabetes was associated with poststroke mortality (OR: 1.33; 95% CI: 1.19-1.49), pneumonia (OR: 1.30; 95% CI: 1.20-1.42), and urinary tract infection (OR: 1.66; 95% CI: 1.55-1.77). The impact of diabetes on adverse events after stroke was investigated particularly in those with diabetes-related complications.Diabetes was associated with stroke risk, and diabetic patients had more adverse events and subsequent mortality after stroke. PMID:26717365

  15. Clinical characteristics of acute lacunar stroke in women: emphasis on gender differences.

    PubMed

    Arboix, Adrià; Blanco-Rojas, Lorena; Oliveres, Montserrat; García-Eroles, Luis; Comes, Emili; Massons, Juan

    2014-06-01

    There are few studies analyzing features of ischemic stroke subtypes in women. We assessed gender differences in lacunar stroke subtype based on data collected from a prospective stroke registry in Barcelona, Spain. Lacunar ischemic stroke was diagnosed in 310 (8.1 %) women and 423 (11.1 %) men of a total of 3,808 consecutive stroke patients included in a prospective hospital-based stroke registry, in Barcelona, Catalonia (Spain), over a period of 19 years. Independent factors for lacunar stroke in women were assessed by multivariate analysis. Women accounted for 42 % of all lacunar stroke patients (n = 733) in the registry and 11.4 % of all patients with ischemic stroke (n = 2,704). Very old age (85 years or older) was found in 20.3 % in women versus 11.1 % in men (P < 0.0001). In the logistic regression analysis, obesity [odds ratio (OR) = 4.24], prolonged hospital stay (>12 days) (OR = 1.59), arterial hypertension (OR = 1.50), and age (OR = 1.06) were significant variables independently associated with lacunar stoke in women, whereas peripheral vascular disease (OR = 0.51), chronic obstructive pulmonary disease (OR = 0.46), renal dysfunction (OR = 0.13), and heavy smoking (OR = 0.04) were independent variables for lacunar stroke in men. Women with lacunar stroke were remarkably older and presented with obesity and hypertension more frequently than did men. Lacunar stroke severity was similar in men and women. These findings in lacunar stroke patients could be explained by differences in gender for ischemic stroke in general.

  16. The emotional stress and risk of ischemic stroke.

    PubMed

    Kotlęga, Dariusz; Gołąb-Janowska, Monika; Masztalewicz, Marta; Ciećwież, Sylwester; Nowacki, Przemysław

    2016-01-01

    Stroke is the second leading cause of death worldwide, and the leading cause of acquired disability in adults in most regions. There have been distinguished modifiable and non-modifiable risk factors of stroke. Among them the emotional stress was presented as a risk factor. The aim of this review was to present available data regarding the influence of acute and chronic mental stress on the risk of ischemic stroke as well as discussing the potential pathomechanisms of such relationship. There is an evident association between both acute and chronic emotional stress and risk of stroke. Several potential mechanisms are discussed to be the cause. Stress can increase the cerebrovascular disease risk by modulating symphaticomimetic activity, affecting the blood pressure reactivity, cerebral endothelium, coagulation or heart rhythm. The emotional stress seems to be still underestimated risk factor in neurological practice and research. Further studies and analyses should be provided for better understanding of this complex, not fully known epidemiological problem.

  17. Stem Cell-Paved Biobridges Facilitate Stem Transplant and Host Brain Cell Interactions for Stroke Therapy

    PubMed Central

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

    2015-01-01

    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 4.5 hours 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. PMID:25770817

  18. Predicting outcome in a postacute stroke rehabilitation programme.

    PubMed

    van Bragt, Peter J; van Ginneken, Berbke T; Westendorp, Tessa; Heijenbrok-Kal, Majanka H; Wijffels, Markus P; Ribbers, Gerard M

    2014-06-01

    This study aims to evaluate and predict outcome as part of routine quality assessment of an inpatient stroke rehabilitation programme. By relating functional outcome to patient characteristics, including variables from the quality of life domain, we aim to find a set of variables that can be useful for prognosis, stratification and programme improvement. Data were collected, before and after rehabilitation, from a prospective quality registration database. Included were 250 patients in inpatient stroke rehabilitation after sustaining a first or recurrent ischemic or haemorrhagic stroke. Functional status was measured with the Barthel Index and the Academic Medical Centre Linear Disability Score. Health-related quality of life (HrQoL) was measured with the COOP/WONCA and the Nottingham Health Profile. Significant improvements were found on all outcome measures. A lower functional admission score, older age, more severe stroke, more pain and more negative emotional reactions on admission were found to be independent predictors of a lower outcome score, explaining 39.5% of its variance. Subjective (HrQoL) factors such as negative emotion and pain have an adverse effect on outcome of stroke rehabilitation, in addition to stroke severity, age and functional status at admission. These factors need to be taken into account in screening, clinical decision making and treatment design. PMID:24300659

  19. Predicting outcome in a postacute stroke rehabilitation programme.

    PubMed

    van Bragt, Peter J; van Ginneken, Berbke T; Westendorp, Tessa; Heijenbrok-Kal, Majanka H; Wijffels, Markus P; Ribbers, Gerard M

    2014-06-01

    This study aims to evaluate and predict outcome as part of routine quality assessment of an inpatient stroke rehabilitation programme. By relating functional outcome to patient characteristics, including variables from the quality of life domain, we aim to find a set of variables that can be useful for prognosis, stratification and programme improvement. Data were collected, before and after rehabilitation, from a prospective quality registration database. Included were 250 patients in inpatient stroke rehabilitation after sustaining a first or recurrent ischemic or haemorrhagic stroke. Functional status was measured with the Barthel Index and the Academic Medical Centre Linear Disability Score. Health-related quality of life (HrQoL) was measured with the COOP/WONCA and the Nottingham Health Profile. Significant improvements were found on all outcome measures. A lower functional admission score, older age, more severe stroke, more pain and more negative emotional reactions on admission were found to be independent predictors of a lower outcome score, explaining 39.5% of its variance. Subjective (HrQoL) factors such as negative emotion and pain have an adverse effect on outcome of stroke rehabilitation, in addition to stroke severity, age and functional status at admission. These factors need to be taken into account in screening, clinical decision making and treatment design.

  20. [Pregnancy and acute ischemic stroke].

    PubMed

    Bereczki, Dániel

    2016-05-15

    Pregnancy-related ischemic strokes play an important role in both maternal and fetal morbidity and mortality. Changes in hemostaseology and hemodynamics as well as risk factors related to or independent from pregnancy contribute to the increased stroke-risk during gestation and the puerperium. Potential teratogenic effects make diagnostics, acute therapy and prevention challenging. Because randomized, controlled trials are not available, a multicenter registry of patients with gestational stroke would be desirable. Until definite guidelines emerge, management of acute ischemic stroke during pregnancy remains individual, involving experts and weighing the risks and benefits.

  1. Radiological Portrait of Embolic Strokes.

    PubMed

    Sachdeva, Gautam; Saeed, Ali; Jani, Vishal; Razak, Anmar

    2016-05-01

    Stroke is the leading cause of adult disability and the fifth leading cause of death in the United States. In 2010, the cost of stroke to the health care system in the United States was estimated to be $71.55 billion, and it is projected to double over the next 20 years. Cardioembolism is a leading pathophysiologic cause of stroke. Along with a careful review of the presenting history and clinical symptomatology, early radiographic studies including computed tomography (CT) and MRI, may demonstrate certain characteristics that may be suggestive of a cardioembolic origin to a stroke of concern. PMID:27150175

  2. Location of lightning stroke on OPGW by use of distributed optical fiber sensor

    NASA Astrophysics Data System (ADS)

    Lu, Lidong; Liang, Yun; Li, Binglin; Guo, Jinghong; Zhang, Hao; Zhang, Xuping

    2014-12-01

    A new method based on a distributed optical fiber sensor (DOFS) to locate the position of lightning stroke on the optical fiber ground wire (OPGW) is proposed and experimentally demonstrated. In the method, the lightning stroke process is considered to be a heat release process at the lightning stroke position, so Brillouin optical time domain reflectometry (BOTDR) with spatial resolution of 2m is used as the distributed temperature sensor. To simulate the lightning stroke process, an electric anode with high pulsed current and a negative electrode (the OPGW) are adopted to form a lightning impulse system with duration time of 200ms. In the experiment, lightning strokes with the quantity of electric discharge of 100 Coul and 200 Coul are generated respectively, and the DOFS can sensitively capture the temperature change of the lightning stroke position in the transient electric discharging process. Experimental results show that DOFS is a feasible instrument to locate the lightning stroke on the OPGW and it has excellent potential for the maintenance of electric power transmission line. Additionally, as the range of lightning stroke is usually within 10cm and the spatial resolution of a typical DOFS is beyond 1m, the temperature characteristics in a small area cannot be accurately represented by a DOFS with a large spatial resolution. Therefore, for further application of distributed optical fiber temperature sensors for lightning stroke location on OPGW, such as BOTDR and ROTDR, it is important to enhance the spatial resolution.

  3. Mannose-Binding Lectin Deficiency Is Associated With Smaller Infarction Size and Favorable Outcome in Ischemic Stroke Patients

    PubMed Central

    Fluri, Felix; Schuetz, Philipp; Bingisser, Roland; Kappos, Ludwig; Steck, Andreas J.; Engelter, Stefan T.; Mueller, Beat; Christ-Crain, Mirjam; Trendelenburg, Marten

    2011-01-01

    Background The Mannose-binding lectin (MBL) pathway of complement plays a pivotal role in the pathogenesis of ischemia/reperfusion (I/R) injury after experimental ischemic stroke. As comparable data in human ischemic stroke are limited, we investigated in more detail the association of MBL deficiency with infarction volume and functional outcome in a large cohort of patients receiving intravenous thrombolysis or conservative treatment. Methodology/Principal Findings In a post hoc analysis of a prospective cohort study, admission MBL concentrations were determined in 353 consecutive patients with an acute ischemic stroke of whom 287 and 66 patients received conservative and thrombolytic treatment, respectively. Stroke severity, infarction volume, and functional outcome were studied in relation to MBL concentrations at presentation to the emergency department. MBL levels on admission were not influenced by the time from symptom onset to presentation (p = 0.53). In the conservative treatment group patients with mild strokes at presentation, small infarction volumes or favorable outcomes after three months demonstrated 1.5 to 2.6-fold lower median MBL levels (p = 0.025, p = 0.0027 and p = 0.046, respectively) compared to patients with more severe strokes. Moreover, MBL deficient patients (<100 ng/ml) were subject to a considerably decreased risk of an unfavorable outcome three months after ischemic stroke (adjusted odds ratio 0.38, p<0.05) and showed smaller lesion volumes (mean size 0.6 vs. 18.4 ml, p = 0.0025). In contrast, no association of MBL concentration with infarction volume or functional outcome was found in the thrombolysis group. However, the small sample size limits the significance of this observation. Conclusions MBL deficiency is associated with smaller cerebral infarcts and favorable outcome in patients receiving conservative treatment. Our data suggest an important role of the lectin pathway in the pathophysiology of cerebral I

  4. Stroke mood screening on an inpatient stroke unit.

    PubMed

    Gurr, Birgit

    Psychological problems, and post-stroke depression in particular, are common following stroke. This article describes the development and evaluation of a mood screening pathway on a hospital-based stroke unit. The pathway is evaluated against the criteria of the national stroke guidelines, particularly the National Stroke Sentinel Audit (Royal College of Physicians, 2008a). The outcome reveals that the Stroke Mood Screening pathway meets the target of assessing every patient in 88.9% of cases. This places the performance of this procedure within the top quarter of stroke units in the UK. The Stroke Mood Screening pathway enabled the rehabilitation team to identify mood disturbances very early following patients' admission to the unit. Good communication pathways between rehabilitation staff and easy referral routes to neuropsychology made rapid and efficient responses to emerging mood problems possible. The outcomes of this evaluation also give useful guidance for service improvements and consequently, could optimize the provision of psychological support for the patients on the unit.

  5. Stroke: advances in medical therapy and acute stroke intervention.

    PubMed

    Barrett, Kevin M; Lal, Brajesh K; Meschia, James F

    2015-10-01

    Evidence-based therapeutic options for stroke continue to emerge based on results from well-designed clinical studies. Ischemic stroke far exceeds hemorrhagic stroke in terms of prevalence and incidence, both in the USA and worldwide. The public health effect of reducing death and disability related to ischemic stroke justifies the resources that have been invested in identifying safe and effective treatments. The emergence of novel oral anticoagulants for ischemic stroke prevention in atrial fibrillation has introduced complexity to clinical decision making for patients with this common cardiac arrhythmia. Some accepted ischemic stroke preventative strategies, such as carotid revascularization for asymptomatic carotid stenosis, require reassessment, given advances in risk factor management, antithrombotic therapy, and surgical techniques. Intra-arterial therapy, particularly with stent retrievers after intravenous tissue plasminogen activator, has recently been demonstrated to improve functional outcomes and will require investment in system-based care models to ensure that effective treatments are received by patients in a timely fashion. The purpose of this review is to describe recent advances in medical and surgical approaches to ischemic stroke prevention and acute treatment. Results from recently published clinical trials will be highlighted along with ongoing clinical trials addressing key questions in ischemic stroke management and prevention where equipoise remains.

  6. Atrial fibrillation is a predictor of in-hospital mortality in ischemic stroke patients

    PubMed Central

    Ong, Cheung-Ter; Wong, Yi-Sin; Wu, Chi-Shun; Su, Yu-Hsiang

    2016-01-01

    Background/purpose In-hospital mortality rate of acute ischemic stroke patients remains between 3% and 18%. For improving the quality of stroke care, we investigated the factors that contribute to the risk of in-hospital mortality in acute ischemic stroke patients. Materials and methods Between January 1, 2007, and December 31, 2011, 2,556 acute ischemic stroke patients admitted to a stroke unit were included in this study. Factors such as demographic characteristics, clinical characteristics, comorbidities, and complications related to in-hospital mortality were assessed. Results Of the 2,556 ischemic stroke patients, 157 received thrombolytic therapy. Eighty of the 2,556 patients (3.1%) died during hospitalization. Of the 157 patients who received thrombolytic therapy, 14 (8.9%) died during hospitalization. History of atrial fibrillation (AF, P<0.01) and stroke severity (P<0.01) were independent risk factors of in-hospital mortality. AF, stroke severity, cardioembolism stroke, and diabetes mellitus were independent risk factors of hemorrhagic transformation. Herniation and sepsis were the most common complications of stroke that were attributed to in-hospital mortality. Approximately 70% of in-hospital mortality was related to stroke severity (total middle cerebral artery occlusion with herniation, basilar artery occlusion, and hemorrhagic transformation). The other 30% of in-hospital mortality was related to sepsis, heart disease, and other complications. Conclusion AF is associated with higher in-hospital mortality rate than in patients without AF. For improving outcome of stroke patients, we also need to focus to reduce serious neurological or medical complications. PMID:27418830

  7. Guideline clinical nutrition in patients with stroke.

    PubMed

    Wirth, Rainer; Smoliner, Christine; Jäger, Martin; Warnecke, Tobias; Leischker, Andreas H; Dziewas, Rainer

    2013-12-01

    Stroke is regularly accompanied by dysphagia and other factors associated with decreased nutritional intake. Dysphagia with aspiration pneumonia and insufficient nutritional intake lead to worse outcome after stroke.This guideline is the first chapter of the guideline "Clinical Nutrition in Neurology" of the German Society for Clinical Nutrition (DGEM) which itself is one part of a comprehensive guideline about all areas of Clinical Nutrition. The thirty-one recommendations of the guideline are based on a systematic literature search and review, last updated December 31, 2011. All recommendations were discussed and consented at several consensus conferences with the entire DGEM guideline group. The recommendations underline the importance of an early screening and assessment of dysphagia and give advice for an evidence based and comprehensive nutritional management to avoid aspiration, malnutrition and dehydration.

  8. Meeting the challenges of stroke in India.

    PubMed

    Mehndiratta, Man Mohan; Singhal, Aneesh B; Chaturvedi, Seemant; Sivakumar, M R; Moonis, Majaz

    2013-06-11

    Worldwide, cerebrovascular diseases are responsible for 6.15 million deaths (10.8% of all deaths)(1) and are the second most common cause of mortality; 87% of stroke deaths occur in low or middle income countries.(2) With the world's second largest population, India is witnessing several adverse trends for the cardiovascular health of its population, including a rapid rise in the proportion of patients with diabetes and dyslipidemia, and the relative lack of exercise among the general population. India has the world's largest population of patients with diabetes, with over 62 million people with diabetes in 2011.(3) At the current time, the population in India is projected to have over 1 million strokes per year. This figure will surely rise in the coming decades due to longer life expectancy and the downstream influence of risk factors such as diabetes. PMID:23751917

  9. Depletion of Cultivatable Gut Microbiota by Broad-Spectrum Antibiotic Pretreatment Worsens Outcome After Murine Stroke

    PubMed Central

    Winek, Katarzyna; Engel, Odilo; Koduah, Priscilla; Heimesaat, Markus M.; Fischer, André; Bereswill, Stefan; Dames, Claudia; Kershaw, Olivia; Gruber, Achim D.; Curato, Caterina; Oyama, Naoki; Meisel, Christian; Meisel, Andreas

    2016-01-01

    Background and Purpose— Antibiotics disturbing microbiota are often used in treatment of poststroke infections. A bidirectional brain–gut microbiota axis was recently suggested as a modulator of nervous system diseases. We hypothesized that gut microbiota may be an important player in the course of stroke. Methods— We investigated the outcome of focal cerebral ischemia in C57BL/6J mice after an 8-week decontamination with quintuple broad-spectrum antibiotic cocktail. These microbiota-depleted animals were subjected to 60 minutes middle cerebral artery occlusion or sham operation. Infarct volume was measured using magnetic resonance imaging, and mice were monitored clinically throughout the whole experiment. At the end point, tissues were preserved for further analysis, comprising histology and immunologic investigations using flow cytometry. Results— We found significantly decreased survival in the middle cerebral artery occlusion microbiota-depleted mice when the antibiotic cocktail was stopped 3 days before surgery (compared with middle cerebral artery occlusion specific pathogen-free and sham-operated microbiota-depleted mice). Moreover, all microbiota-depleted animals in which antibiotic treatment was terminated developed severe acute colitis. This phenotype was rescued by continuous antibiotic treatment or colonization with specific pathogen-free microbiota before surgery. Further, infarct volumes on day one did not differ between any of the experimental groups. Conclusions— Conventional microbiota ensures intestinal protection in the mouse model of experimental stroke and prevents development of acute and severe colitis in microbiota-depleted mice not given antibiotic protection after cerebral ischemia. Our experiments raise the clinically important question as to whether microbial colonization or specific microbiota are crucial for stroke outcome. PMID:27056982

  10. Stroke-Related Translational Research

    PubMed Central

    Caplan, Louis R.; Arenillas, Juan; Cramer, Steven C.; Joutel, Anne; Lo, Eng H.; Meschia, James; Savitz, Sean; Tournier-Lasserve, Elizabeth

    2013-01-01

    Stroke-related translational research is multifaceted. Herein, we highlight genome-wide association studies and genetic studies of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, COL4A1 mutations, and cerebral cavernous malformations; advances in molecular biology and biomarkers; newer brain imaging research; and recovery from stroke emphasizing cell-based and other rehabilitative modalities. PMID:21555605

  11. One Stroke at a Time

    ERIC Educational Resources Information Center

    Hollibaugh, Molly

    2012-01-01

    At first glance, a Zentangle creation can seem intricate and complicated. But, when you learn how it is done, you realize how simple it is. Zentangles are patterns, or "tangles," that have been reduced to a simple sequence of elemental strokes. When you learn to focus on each stroke you find yourself capable of things that you may have once…

  12. Oxidative phosphorylation and lacunar stroke

    PubMed Central

    Anderson, Christopher D.; Hurford, Robert; Bevan, Steve; Markus, Hugh S.

    2016-01-01

    Objective: We investigated whether oxidative phosphorylation (OXPHOS) abnormalities were associated with lacunar stroke, hypothesizing that these would be more strongly associated in patients with multiple lacunar infarcts and leukoaraiosis (LA). Methods: In 1,012 MRI-confirmed lacunar stroke cases and 964 age-matched controls recruited from general practice surgeries, we investigated associations between common genetic variants within the OXPHOS pathway and lacunar stroke using a permutation-based enrichment approach. Cases were phenotyped using MRI into those with multiple infarcts or LA (MLI/LA) and those with isolated lacunar infarcts (ILI) based on the number of subcortical infarcts and degree of LA, using the Fazekas grading. Using gene-level association statistics, we tested for enrichment of genes in the OXPHOS pathway with all lacunar stroke and the 2 subtypes. Results: There was a specific association with strong evidence of enrichment in the top 1% of genes in the MLI/LA (subtype p = 0.0017) but not in the ILI subtype (p = 1). Genes in the top percentile for the all lacunar stroke analysis were not significantly enriched (p = 0.07). Conclusions: Our results implicate the OXPHOS pathway in the pathogenesis of lacunar stroke, and show the association is specific to patients with the MLI/LA subtype. They show that MRI-based subtyping of lacunar stroke can provide insights into disease pathophysiology, and imply that different radiologic subtypes of lacunar stroke subtypes have distinct underlying pathophysiologic processes. PMID:26674331

  13. Musculoskeletal problems in stroke survivors.

    PubMed

    Kendall, Richard

    2010-01-01

    Musculoskeletal problems in stoke survivors are common reasons for disability and pain. Shoulder pain is present in 24% of stroke survivors among all complications, second only to depression in 26%. Diagnosis and treatment of the various shoulder pain etiologies can significantly improve quality of life in these patients. This article reviews the common etiologies and treatments of shoulder and hip pain in stroke survivors.

  14. Variants in the inflammatory IL6 and MPO genes modulate stroke susceptibility through main effects and gene–gene interactions

    PubMed Central

    Manso, Helena; Krug, Tiago; Sobral, João; Albergaria, Isabel; Gaspar, Gisela; Ferro, José M; Oliveira, Sofia A; Vicente, Astrid M

    2011-01-01

    There is substantial evidence that inflammation within the central nervous system contributes to stroke risk and recovery. Inflammatory conditions increase stroke risk, and the inflammatory response is of major importance in recovery and healing processes after stroke. We investigated the role of inflammatory genes IL1B, IL6, MPO, and TNF in stroke susceptibility and recovery in a population sample of 672 patients and 530 controls, adjusting for demographic, clinical and lifestyle risk factors, and stroke severity parameters. We also considered the likely complexity of inflammatory mechanisms in stroke, by assessing the combined effects of multiple genes. Two interleukin 6 (IL6) and one myeloperoxidase (MPO) single-nucleotide polymorphisms were significantly associated with stroke risk (0.022stroke risk. An epistatic interaction between the IL6 and MPO genes was also identified in association with stroke susceptibility (P=0.031 after 1,000 permutations). In a subset of 546 patients, one IL6 haplotype was associated with stroke outcome at 3 months (correctedP=0.024), an intriguing finding warranting further validation. Our findings support the association of the IL6 gene and present novel evidence for the involvement of MPO in stroke susceptibility, suggesting a modulation of stroke risk by main gene effects, clinical and lifestyle factors, and gene–gene interactions. PMID:21407237

  15. The collagen-binding protein of Streptococcus mutans is involved in haemorrhagic stroke

    PubMed Central

    Nakano, Kazuhiko; Hokamura, Kazuya; Taniguchi, Naho; Wada, Koichiro; Kudo, Chiho; Nomura, Ryota; Kojima, Ayuchi; Naka, Shuhei; Muranaka, Yoshinori; Thura, Min; Nakajima, Atsushi; Masuda, Katsuhiko; Nakagawa, Ichiro; Speziale, Pietro; Shimada, Nobumitsu; Amano, Atsuo; Kamisaki, Yoshinori; Tanaka, Tokutaro; Umemura, Kazuo; Ooshima, Takashi

    2011-01-01

    Although several risk factors for stroke have been identified, one-third remain unexplained. Here we show that infection with Streptococcus mutans expressing collagen-binding protein (CBP) is a potential risk factor for haemorrhagic stroke. Infection with serotype k S. mutans, but not a standard strain, aggravates cerebral haemorrhage in mice. Serotype k S. mutans accumulates in the damaged, but not the contralateral hemisphere, indicating an interaction of bacteria with injured blood vessels. The most important factor for high-virulence is expression of CBP, which is a common property of most serotype k strains. The detection frequency of CBP-expressing S. mutans in haemorrhagic stroke patients is significantly higher than in control subjects. Strains isolated from haemorrhagic stroke patients aggravate haemorrhage in a mouse model, indicating that they are haemorrhagic stroke-associated. Administration of recombinant CBP causes aggravation of haemorrhage. Our data suggest that CBP of S. mutans is directly involved in haemorrhagic stroke. PMID:21952219

  16. Swimmer detection and pose estimation for continuous stroke-rate determination

    NASA Astrophysics Data System (ADS)

    Zecha, Dan; Greif, Thomas; Lienhart, Rainer

    2012-02-01

    In this work we propose a novel approach to automatically detect a swimmer and estimate his/her pose continuously in order to derive an estimate of his/her stroke rate given that we observe the swimmer from the side. We divide a swimming cycle of each stroke into several intervals. Each interval represents a pose of the stroke. We use specifically trained object detectors to detect each pose of a stroke within a video and count the number of occurrences per time unit of the most distinctive poses (so-called key poses) of a stroke to continuously infer the stroke rate. We extensively evaluate the overall performance and the influence of the selected poses for all swimming styles on a data set consisting of a variety of swimmers.

  17. Stroke rehabilitation research needs to be different to make a difference.

    PubMed

    Stinear, Cathy M

    2016-01-01

    Stroke continues to be a major cause of adult disability. In contrast to progress in stroke prevention and acute medical management, there have been no major breakthroughs in rehabilitation therapies. Most stroke rehabilitation trials are conducted with patients at the chronic stage of recovery and this limits their translation to clinical practice. Encouragingly, several multi-centre rehabilitation trials, conducted during the first few weeks after stroke, have recently been reported; however, all were negative. There is a renewed focus on improving the quality of stroke rehabilitation research through greater harmonisation and standardisation of terminology, trial design, measures, and reporting. However, there is also a need for more pragmatic trials to test interventions in a way that assists their translation to clinical practice. Novel interventions with a strong mechanistic rationale need to be tested in both explanatory and pragmatic trials if we are to make a meaningful difference to stroke rehabilitation practice and outcomes.

  18. Relationship between stroke volume and pulse pressure during blood volume perturbation: a mathematical analysis.

    PubMed

    Bighamian, Ramin; Hahn, Jin-Oh

    2014-01-01

    Arterial pulse pressure has been widely used as surrogate of stroke volume, for example, in the guidance of fluid therapy. However, recent experimental investigations suggest that arterial pulse pressure is not linearly proportional to stroke volume. However, mechanisms underlying the relation between the two have not been clearly understood. The goal of this study was to elucidate how arterial pulse pressure and stroke volume respond to a perturbation in the left ventricular blood volume based on a systematic mathematical analysis. Both our mathematical analysis and experimental data showed that the relative change in arterial pulse pressure due to a left ventricular blood volume perturbation was consistently smaller than the corresponding relative change in stroke volume, due to the nonlinear left ventricular pressure-volume relation during diastole that reduces the sensitivity of arterial pulse pressure to perturbations in the left ventricular blood volume. Therefore, arterial pulse pressure must be used with care when used as surrogate of stroke volume in guiding fluid therapy.

  19. Stroke education in the Philippines.

    PubMed

    Navarro, Jose C; Baroque, Alejandro C; Lokin, Johnny K

    2013-10-01

    Education is paramount in effectively reducing the significant burden of stroke in the Philippines. Dedicated academic institutions and dynamic professional organizations in the Philippines have collaborated to involve themselves in the plight against stroke through systematic curriculum development for undergraduates, continuous regulation of quality residency and fellowship training program, hosting up-to-date Continuing Medical Education (CME) activities for local and international audience, and active participation in clinical stroke trials. Most recently, the University of Santo Tomas Faculty of Medicine & Surgery and the Department of Neurology & Psychiatry offered a 72-hour Certification Course in Stroke Medicine that commenced in 2011 in anticipation of the Master on Health Sciences in Stroke Medicine course being prepared for 2013. PMID:23506562

  20. Acute Stroke Imaging Research Roadmap

    PubMed Central

    Wintermark, Max; Albers, Gregory W.; Alexandrov, Andrei V.; Alger, Jeffry R.; Bammer, Roland; Baron, Jean-Claude; Davis, Stephen; Demaerschalk, Bart M.; Derdeyn, Colin P.; Donnan, Geoffrey A.; Eastwood, James D.; Fiebach, Jochen B.; Fisher, Marc; Furie, Karen L.; Goldmakher, Gregory V.; Hacke, Werner; Kidwell, Chelsea S.; Kloska, Stephan P.; Köhrmann, Martin; Koroshetz, Walter; Lee, Ting-Yim; Lees, Kennedy R.; Lev, Michael H.; Liebeskind, David S.; Ostergaard, Leif; Powers, William J.; Provenzale, James; Schellinger, Peter; Silbergleit, Robert; Sorensen, Alma Gregory; Wardlaw, Joanna; Wu, Ona; Warach, Steven

    2009-01-01

    The recent “Advanced Neuroimaging for Acute Stroke Treatment” meeting on September 7 and 8, 2007 in Washington DC, brought together stroke neurologists, neuroradiologists, emergency physicians, neuroimaging research scientists, members of the National Institute of Neurological Disorders and Stroke (NINDS), the National Institute of Biomedical Imaging and Bioengineering (NIBIB), industry representatives, and members of the US Food and Drug Administration (FDA) to discuss the role of advanced neuroimaging in acute stroke treatment. The goals of the meeting were to assess state-of-the-art practice in terms of acute stroke imaging research and to propose specific recommendations regarding: (1) the standardization of perfusion and penumbral imaging techniques, (2) the validation of the accuracy and clinical utility of imaging markers of the ischemic penumbra, (3) the validation of imaging biomarkers relevant to clinical outcomes, and (4) the creation of a central repository to achieve these goals. The present article summarizes these recommendations and examines practical steps to achieve them. PMID:18477656

  1. Stroke education in the Philippines.

    PubMed

    Navarro, Jose C; Baroque, Alejandro C; Lokin, Johnny K

    2013-10-01

    Education is paramount in effectively reducing the significant burden of stroke in the Philippines. Dedicated academic institutions and dynamic professional organizations in the Philippines have collaborated to involve