Summary Thrombolysis with alteplase administered within a narrow therapeutic window provides an effective therapy for acute ischaemic stroke. However, mainly because of prehospital delay, patients ...often arrive too late for treatment, and no more than 1–8% of patients with stroke obtain this treatment. We recommend that all links in the prehospital stroke rescue chain must be optimised so that in the future more than a small minority of patients can profit from time-sensitive acute stroke therapy. Measures for improvement include continuous public awareness campaigns, education of emergency medical service personnel, the use of standardised, validated scales for recognition of stroke symptoms and for triaging to the appropriate institution, and advance notification to the receiving hospital. In the future, use of telemedicine technologies for interaction between the emergency site and hospital, and the strategy of treatment directly at the emergency site (mobile stroke unit concept), could contribute to more efficient use of resources and reduce the time taken to instigate treatment to within 60 min—the golden hour—of the onset of the symptoms of stroke.
Summary In acute stroke management, time is brain. Bringing swift treatment to the patient, instead of the conventional approach of awaiting the patient's arrival at the hospital for treatment, is a ...potential strategy to improve clinical outcomes after stroke. This strategy is based on the use of an ambulance (mobile stroke unit) equipped with an imaging system, a point-of-care laboratory, a telemedicine connection to the hospital, and appropriate medication. Studies of prehospital stroke treatment consistently report a reduction in delays before thrombolysis and cause-based triage in regard to the appropriate target hospital (eg, primary vs comprehensive stroke centre). Moreover, novel medical options for the treatment of stroke patients are also under investigation, such as prehospital differential blood pressure management, reversal of warfarin effects in haemorrhagic stroke, and management of cerebral emergencies other than stroke. However, crucial concerns regarding safety, clinical efficacy, best setting, and cost-effectiveness remain to be addressed in further studies. In the future, mobile stroke units might allow the investigation of novel diagnostic (eg, biomarkers and automated imaging evaluation) and therapeutic (eg, neuroprotective drugs and treatments for haemorrhagic stroke) options in the prehospital setting, thus functioning as a tool for research on prehospital stroke management.
Summary Background Only 2–5% of patients who have a stroke receive thrombolytic treatment, mainly because of delay in reaching the hospital. We aimed to assess the efficacy of a new approach of ...diagnosis and treatment starting at the emergency site, rather than after hospital arrival, in reducing delay in stroke therapy. Methods We did a randomised single-centre controlled trial to compare the time from alarm (emergency call) to therapy decision between mobile stroke unit (MSU) and hospital intervention. For inclusion in our study patients needed to be aged 18–80 years and have one or more stroke symptoms that started within the previous 2·5 h. In accordance with our week-wise randomisation plan, patients received either prehospital stroke treatment in a specialised ambulance (equipped with a CT scanner, point-of-care laboratory, and telemedicine connection) or optimised conventional hospital-based stroke treatment (control group) with a 7 day follow-up. Allocation was not masked from patients and investigators. Our primary endpoint was time from alarm to therapy decision, which was analysed with the Mann-Whitney U test. Our secondary endpoints included times from alarm to end of CT and to end of laboratory analysis, number of patients receiving intravenous thrombolysis, time from alarm to intravenous thrombolysis, and neurological outcome. We also assessed safety endpoints. This study is registered with ClinicalTrials.gov , number NCT00792220. Findings We stopped the trial after our planned interim analysis at 100 of 200 planned patients (53 in the prehospital stroke treatment group, 47 in the control group), because we had met our prespecified criteria for study termination. Prehospital stroke treatment reduced the median time from alarm to therapy decision substantially: 35 min (IQR 31–39) versus 76 min (63–94), p<0·0001; median difference 41 min (95% CI 36–48 min). We also detected similar gains regarding times from alarm to end of CT, and alarm to end of laboratory analysis, and to intravenous thrombolysis for eligible ischaemic stroke patients, although there was no substantial difference in number of patients who received intravenous thrombolysis or in neurological outcome. Safety endpoints seemed similar across the groups. Interpretation For patients with suspected stroke, treatment by the MSU substantially reduced median time from alarm to therapy decision. The MSU strategy offers a potential solution to the medical problem of the arrival of most stroke patients at the hospital too late for treatment. Funding Ministry of Health of the Saarland, Germany, the Werner-Jackstädt Foundation, the Else-Kröner-Fresenius Foundation, and the Rettungsstiftung Saar.
Abstract In Alzheimer's disease (AD), Parkinson's disease (PD), dementia with Lewy bodies (DLB) and amyotrophic lateral sclerosis (ALS), neuroinflammatory responses are considered to contribute to ...neuronal injury. Recently, the innate immune receptors, toll-like receptors (TLRs) and the LPS receptor (CD14) have been related to neurodegeneration. In this study, we systematically assessed the expression of most TLRs and CD14 in AD, PD/DLB and ALS using murine models of these diseases and human post-mortem brain tissues. A common upregulation of TLR2 and CD14 was found in all three animal models. While these two receptors could also be detected in AD patient tissues, they were absent from DLB and ALS tissues. This uniform pattern of innate immune response in animal models of neurodegenerative diseases clearly indicates that this response is part of a non-specific neuroinflammatory effector phase rather than a disease-specific event. The less dynamic disease progression in humans and the location (extracellular versus intracellular) of the aggregated proteins deposits might explain the divergent results seen between animal models and human tissues.
Multiple Sclerosis (MS) is the most common cause for permanent disability in young adults. Current pathophysiological understanding has identified an autoaggressive immune reaction with infiltration ...of immune cells into the central nervous system and local inflammatory and demyelinating reactions. The current therapy focuses on a modulation or suppression of immune functions. Sphingolipids, main components of nervous tissue, have been linked to MS already 60 years ago with the description of an unusual myelin lipid distribution in diseased patients. There is tremendous information developing on the role of different sphingolipids in MS. Antibodies against sphingomyelin, sulfatide or galacosylceramide have been detected in serum or CSF of MS patients, although up to now, this knowledge did not find its way into clinical use. Ceramide and the enzymes linked to its production have been described to play a pivotal role in oligendrocyte damage and demyelination. Nowadays, especially sphingosine-1-phosphate (S1P) is in the focus of pathophysiological research and therapy development. A S1P analogue, FTY720, is a widely distributed therapy against relapsing-remitting MS, attenuating the emigration of activated, autoreactive lymphocytes from lymph nodes, thereby preventing new inflammatory infiltration into the central nervous system. Beside, there is more and more evidence, that especially S1P receptors on oligodendrocytes and astrocytes are involved in demyelination processes and subsequent axonal degeneration, important features of chonic progressive MS disease course. Further information and research on the manifold role of sphingolipids are needed to prepare the ground for further clinical trials. This review focuses on the current knowledge of the role of sphingolipids in MS and describes the current therapeutical implications.
BACKGROUND AND PURPOSE—A new generation of carotid artery stents that uses a second micromesh layer to reduce embolic events during carotid artery stenting has recently been introduced. The purpose ...of this study was to compare acute occlusion rates of these new dual-layer stents with those of single-layer stents in the setting of emergency carotid artery stenting with intracranial mechanical thrombectomy in acute ischemic stroke.
METHODS—Consecutive patients with acute tandem (intra- and extracranial) lesions of the anterior circulation who were endovascularly treated at our institution were identified from our registry of neuroendovascular interventions. Clinical, angiographic, and neuroimaging data were analyzed. End points included acute occlusions of the carotid stents (within 72 hours after stenting) and symptomatic intracerebral hemorrhage.
RESULTS—Forty-seven patients were included. Dual-layer stents (n=20) had a significantly higher rate of acute occlusions than single-layer stents (n=27; 45% versus 3.7%; P=0.001; odds ratio, 21.3; 95% confidence interval, 2.4–188.4). There were no significant differences in the rates of patients who had any antiplatelet or dual antiplatelet medication before admission, in the rates of postinterventional symptomatic intracerebral hemorrhage, the mean National Institutes of Health Stroke Scale scores at admission, or the modified Rankin Scale scores at discharge.
CONCLUSIONS—The recently introduced dual-layer stents have a higher risk of acute occlusion compared with single-layer stents in the treatment of acute stroke.
The cuprizone animal model, also known as the toxic demyelination model, is a well-reproducible model of demyelination- and remyelination in mice, and has been useful in studying important aspect of ...human demyelinating diseases, including multiple sclerosis. In this study, we investigated the role of acid sphingomyelinase in demyelination and myelin repair by inducing acute and chronic demyelination with 5- or 12-week cuprizone treatment, followed by a 2-week cuprizone withdrawal phase to allow myelin repair. Sphingolipids, in particular ceramide and the enzyme acid sphingomyelinase, which generates ceramide from sphingomyelin, seem to be involved in astrocyte activation and neuronal damage in multiple sclerosis. We used immunohistochemistry to study glial reaction and oligodendrocyte distribution in acid sphingomyelinase deficient mice and wild-type C57BL/6J littermates at various time intervals after demyelination and remyelination. Axonal injury was quantified using amyloid precursor protein and synaptophysin, and gene expression and protein levels were measured using gene analysis and Western blotting, respectively. Our results show that mice lacking acid sphingomyelinase had a significant increase in myelin recovery and a significantly higher oligodendrocyte cell count after 2 weeks remyelination compared to wild-type littermates. Detrimental astroglial distribution was also significantly reduced in acid sphingomyelinase deficient animals. We obtained similar results in experiments using amitriptyline to inhibit acid sphingomyelinase. These findings suggest that acid sphingomyelinase plays a significant role in myelin repair, and its inhibition by amitriptyline may constitute a novel therapeutic approach for multiple sclerosis patients.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Major depressive disorder is a severe and chronic illness with high lifetime prevalence and a high incidence of suicide as the cause of death for patients with this diagnosis. Major depressive ...disorder is often treated with anti‐depressants. Although these drugs have been used for many years, their exact mode of action is still unknown. It has been suggested that many anti‐depressants act by increasing the concentrations of serotonergic transmitters in the synaptic space. However, recent studies have examined the effects of anti‐depressants on neurogenesis in the hippocampus, the restoration of hippocampal neuronal networks that may be affected by major depression, and the regulation of the hypothalamic–pituitary–adrenal axis by immature neurons in the hippocampus. Here, we present and discuss a novel hypothesis suggesting that these events are regulated by the concentrations of sphingolipids, in particular ceramide, in the hippocampus. These concepts suggest that the acid sphingomyelinase/ceramide system plays a central role in the pathogenesis of major depression and may be a novel target for anti‐depressants.
Major depressive disorder is a severe and chronic illness with high lifetime prevalence and high incidence of suicide. Major depression is caused in part by an imbalance between factors that positively and negatively control neurogenesis. Anti‐depressants inhibit the acid sphingomyelinase/ceramide system and thereby reduce the sum of negative factors restoring neurogenesis, neuronal survival, and improved mood.
Major depressive disorder is a severe and chronic illness with high lifetime prevalence and high incidence of suicide. Major depression is caused in part by an imbalance between factors that positively and negatively control neurogenesis. Anti‐depressants inhibit the acid sphingomyelinase/ceramide system and thereby reduce the sum of negative factors restoring neurogenesis, neuronal survival, and improved mood.
Microglial activation is a key feature in Alzheimer’s disease and is considered to contribute to progressive neuronal injury by release of neurotoxic products. The innate immune receptor ...Toll-like-receptor 4 (TLR4), localized on the surface of microglia, is a first-line host defense receptor against invading microorganisms. Here, we show that a spontaneous loss-of-function mutation in the Tlr4 gene strongly inhibits microglial and monocytic activation by aggregated Alzheimer amyloid peptide resulting in a significantly lower release of the inflammatory products IL-6, TNFα and nitric oxide. Treatment of primary murine neuronal cells with supernatant of amyloid peptide-stimulated microglia demonstrates that Tlr4 contributes to amyloid peptide-induced microglial neurotoxicity. In addition, stimulation experiments in transfected HEK293 cells allowed to define a tri-molecular receptor complex consisting of TLR4, MD-2 and CD14 necessary for full cellular activation by aggregated amyloid peptide. A clinical relevance of these findings is supported by a marked upregulation of Tlr4 mRNA in APP transgenic mice and by an increased expression of TLR4 in Alzheimer’s disease brain tissue associated with amyloid plaque deposition. Together, these observations provide the first evidence for a role of the key innate immune receptor, TLR4, in neuroinflammation in Alzheimer’s disease.
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