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OBJECTIVE: Approximately 20% of strokes are embolic strokes of undetermined source (ESUS). Undetected atrial fibrillation (AF) remains an important cause. Yet, oral anticoagulation in unselected ESUS patients failed in secondary stroke prevention. Guidance on effective AF detection is lacking. Here, we introduce a novel, non-invasive AF risk assessment after ESUS. METHODS: Catch-Up ESUS is an investigator-initiated, observational cohort study conducted between 2018 and 2019 at the Munich University Hospital. Besides clinical characteristics, patients received ≥72 h digital electrocardiogram recordings to generate the rhythm irregularity burden. Uni- and multivariable regression models predicted the primary endpoint of incident AF, ascertained by standardized follow-up including implantable cardiac monitors. Predictors included the novel rhythm irregularity burden constructed from digital electrocardiogram recordings. We independently validated our model in ESUS patients from the University Hospital Tübingen, Germany. RESULTS: A total of 297 ESUS patients were followed for 15.6 ± 7.6 months. Incident AF (46 patients, 15.4%) occurred after a median of 105 days (25th to 75th percentile 31-33 days). Secondary outcomes were recurrent stroke in 7.7% and death in 6.1%. Multivariable-adjusted analyses identified the rhythm irregularity burden as the strongest AF-predictor (hazard ratio 3.12, 95% confidence interval 1.62-5.80, p < 0001) while accounting for the known risk factors age, CHA2 DS2 -VASc-Score, and NT-proBNP. Independent validation confirmed the rhythm irregularity burden as the most significant AF-predictor (hazard ratio 2.20, 95% confidence interval 1.45-3.33, p < 0001). INTERPRETATION: The novel, non-invasive, electrocardiogram-based rhythm irregularity burden may help adjudicating AF risk after ESUS, and subsequently guide AF-detection after ESUS. Clinical trials need to clarify if high-AF risk patients benefit from tailored secondary stroke prevention. ANN NEUROL 2023;93:479-488.
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Fibrilação Atrial , AVC Embólico , Embolia Intracraniana , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , AVC Embólico/complicações , Medição de Risco , Fatores de Risco , Embolia Intracraniana/etiologiaRESUMO
INTRODUCTION: The World Stroke Organization (WSO) Brain & Heart Task Force developed the Brain & hEart globAl iniTiative (BEAT), a pilot feasibility implementation program to establish clinical collaborations between cardiologists and stroke physicians who work at large healthcare facilities. METHODS: The WSO BEAT pilot project focused on atrial fibrillation (AF) and patent foramen ovale (PFO) detection and management, and poststroke cardiovascular complications known as the stroke-heart syndrome. The program included 10 sites from 8 countries: Brazil, China, Egypt, Germany, Japan, Mexico, Romania, and the USA The primary composite feasibility outcome was the achievement of the following 3 implementation metrics (1) developing site-specific clinical pathways for the diagnosis and management of AF, PFO, and the stroke-heart syndrome; (2) establishing regular Neurocardiology rounds (e.g., monthly); and (3) incorporating a cardiologist to the stroke team. The secondary objectives were (1) to identify implementation challenges to guide a larger program and (2) to describe qualitative improvements. RESULTS: The WSO BEAT pilot feasibility program achieved the prespecified primary composite outcome in 9 of 10 (90%) sites. The most common challenges were the limited access to specific medications (e.g., direct oral anticoagulants) and diagnostic (e.g., prolonged cardiac monitoring) or therapeutic (e.g., PFO closure devices) technologies. The most relevant qualitative improvement was the achievement of a more homogeneous diagnostic and therapeutic approach. CONCLUSION: The WSO BEAT pilot program suggests that developing neurocardiology collaborations is feasible. The long-term sustainability of the WSO BEAT program and its impact on quality of stroke care and clinical outcomes needs to be tested in a larger and longer duration program.
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Fibrilação Atrial , Forame Oval Patente , Acidente Vascular Cerebral , Humanos , Projetos Piloto , Fatores de Risco , Cateterismo Cardíaco/efeitos adversos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/etiologia , Forame Oval Patente/diagnóstico , Forame Oval Patente/diagnóstico por imagem , Fibrilação Atrial/diagnóstico , Prevenção Secundária , Encéfalo , Resultado do Tratamento , RecidivaRESUMO
BACKGROUND: CHANTER (Cerebellar Hippocampal and Basal Nuclei Transient Edema with Restricted diffusion) is a recently described syndrome occurring in the context of drug abuse. While clinical findings are rather unspecific (disorientation, unresponsiveness), MR imaging (MRI) discloses a characteristic pattern (restricted diffusion in the basal ganglia and hippocampi, cerebellar oedema and haemorrhage), allowing for timely diagnosis before complications such as cerebellar swelling and herniation do occur. Here we report a case of CHANTER primarily based on imaging findings, as there was no evidence of drug abuse on admission. CASE PRESENTATION: A 62-year-old Patient was admitted to our hospital after being unresponsive at home. Prehospital intubation was performed, which limited neurological assessment. Under these circumstances no obvious symptoms could be determined, i.e. pupils were isocoric and responsive, and there were no signs of seizures. While the initial CT scan was unremarkable, the subsequent MRI scan showed a distinct imaging pattern: moderately enhancing areas in the basal ganglia and hippocampi with diffusion restriction, accompanied by cerebellar haemorrhage and oedema (Figs. 1 and 2). A comprehensive clinical and laboratory work-up was performed, including drug screening, spinal tap, Holter ECG, echocardiography and EEG. The only conspicuous anamnestic finding was a chronic pain syndrome whose medication had been supplemented with opioids two months previously. The opioid medication was discontinued, which led to a rapid improvement in the patient's clinical condition without any further measures. The patient was able to leave the intensive care unit and was discharged 10 days after admission without persistent neurological deficits. CONCLUSION: Familiarity with typical MRI patterns of toxic encephalopathy in patients from high-risk groups, such as drug abusers, is crucial in emergency neuroradiology. In the presence of typical MRI findings, CHANTER syndrome should be included in the differential diagnosis, even if there is no history of drug abuse, to avoid delay in diagnosis and treatment.
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Imageamento por Ressonância Magnética , Humanos , Pessoa de Meia-Idade , Gânglios da Base/diagnóstico por imagem , Gânglios da Base/patologia , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/induzido quimicamente , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Imageamento por Ressonância Magnética/métodos , SíndromeRESUMO
BACKGROUND: Atrial fibrillation (AF) is one of the most frequent causes of stroke. Several randomized trials have shown that prolonged monitoring increases the detection of AF, but the effect on reducing recurrent cardioembolism, ie, ischemic stroke and systemic embolism, remains unknown. We aim to evaluate whether a risk-adapted, intensified heart rhythm monitoring with consequent guideline conform treatment, which implies initiation of oral anticoagulation (OAC), leads to a reduction of recurrent cardioembolism. METHODS: Find-AF 2 is a randomized, controlled, open-label parallel multicenter trial with blinded endpoint assessment. 5,200 patients ≥ 60 years of age with symptomatic ischemic stroke within the last 30 days and without known AF will be included at 52 study centers with a specialized stroke unit in Germany. Patients without AF in an additional 24-hour Holter ECG after the qualifying event will be randomized in a 1:1 fashion to either enhanced, prolonged and intensified ECG-monitoring (intervention arm) or standard of care monitoring (control arm). In the intervention arm, patients with a high risk of underlying AF will receive continuous rhythm monitoring using an implantable cardiac monitor (ICM) whereas those without high risk of underlying AF will receive repeated 7-day Holter ECGs. The duration of rhythm monitoring within the control arm is up to the discretion of the participating centers and is allowed for up to 7 days. Patients will be followed for at least 24 months. The primary efficacy endpoint is the time until recurrent ischemic stroke or systemic embolism occur. CONCLUSIONS: The Find-AF 2 trial aims to demonstrate that enhanced, prolonged and intensified rhythm monitoring results in a more effective prevention of recurrent ischemic stroke and systemic embolism compared to usual care.
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Fibrilação Atrial , Embolia , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Lactente , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Furilfuramida , Estudos Prospectivos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/diagnóstico , Eletrocardiografia Ambulatorial/métodos , Embolia/diagnóstico , Embolia/etiologia , Embolia/prevenção & controleRESUMO
Recovery processes after stroke include restoration or compensation of function initially lost or newly acquired after injury. Therapeutic interventions can either directly improve these processes and/or inhibit processes that impede regeneration. Numerous experimental studies suggested a great opportunity for such treatments, but the results from recent large clinical trials with neuromodulators such as dopamine and fluoxetine have been rather disappointing. The reasons for this are manifold and involve the extrapolation of results from animal models to humans. Given the differences between animals and humans in genetic and epigenetic background, brain size and anatomy, cerebral vascular anatomy, immune system, as well as clinical function, and behavior, direct extrapolation is unlikely to work. Backward blockades include the incompatible adaption of clinical trial objectives and outcomes in clinical trials with regard to previous preclinical findings. For example, the clinical recovery trial design widely varies and has been characterized by the selection of different clinical endpoints, the inclusion a wide spectrum of stroke subtypes and clinical syndromes, and different time windows for treatment initiation after onset of infarction. This review will discuss these aspects based on the results of the recent stroke recovery trials with the aim to contributing to the development of a therapy that improves the functional outcome of a chronic stroke patient.
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Acidente Vascular Cerebral , Animais , Humanos , Acidente Vascular Cerebral/tratamento farmacológico , Fluoxetina/uso terapêuticoRESUMO
The global SARS-CoV-2 pandemic has contributed to more than 163 million confirmed infections and 3.3 million deaths worldwide. The severity of the pandemic has led to an unprecedented effort to develop multiple effective vaccines. Due to excellent safety and efficacy data from clinical trials, several vaccines were approved. We report a case series of postvaccinal encephalitis in temporal correlation to vaccination with ChAdOx1 nCov-19. The diagnostic criteria for possible autoimmune encephalitis were fulfilled. Our patients responded well to immunosuppressive therapy with corticosteroids. The incidence has been estimated to be approximately 8 per 10 million vaccine doses. Complication of postvaccinal encephalitis after ChAdOx1 nCoV-19 vaccination still appear to be very rare, but need to be diagnosed and treated adequately. Large pooled data from observational epidemiologic studies are necessary to verify causality. ANN NEUROL 2021;90:506-511.
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Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , Encefalomielite Aguda Disseminada/induzido quimicamente , Encefalomielite Aguda Disseminada/diagnóstico por imagem , ChAdOx1 nCoV-19 , Encefalomielite Aguda Disseminada/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
OBJECTIVE: The authors investigated for presence of cognitive impairment after occurrence of bilateral lesions of the genu of the internal capsule (GIC). Clinical and neuropsychological features of unilateral GIC lesions have previously been studied, but the cognitive profile of bilateral lesions of the GIC has not been fully explored. METHODS: An investigation was conducted of neurocognitive deficits and computerized tomography MRI findings among 4,200 stroke patients with bilateral GIC involvement who were admitted to the hospital between January 2010 and October 2018. RESULTS: Eight patients with bilateral lesions of the capsular genu were identified and their data analyzed. Overall, behavioral and cognitive dysfunction were characterized by impairment of frontal, memory, and executive functions. Attention and abstraction were present among all eight patients (100%); apathy, abulia, and executive dysfunctions, among seven (87.5%); global mental dysfunction and planning deficits, among six (75.0%); short-term verbal memory deficits and language dysfunctions, among five (62.5%); long-term verbal memory deficits, among four (50.0%); and spatial memory deficits, reading, writing, counting dysfunctions, and anarthria, among two (25.0%). Four of the patients (50.0%) without a history of cognitive disorder showed severe mental deterioration compatible with the clinical picture of dementia. A clinical picture of dementia was still present in these patients 6 months after stroke. CONCLUSIONS: Bilateral lesions of the capsular genu appearing either simultaneously or at different times were significantly associated with executive dysfunctions.
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Disfunção Cognitiva , Demência , Acidente Vascular Cerebral , Disfunção Cognitiva/etiologia , Humanos , Transtornos da Memória , Testes Neuropsicológicos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagemRESUMO
OBJECTIVE: To analyze why numerous acute stroke treatments were successful in the laboratory but failed in large clinical trials. METHODS: We searched all phase 3 trials of medical treatments for acute ischemic stroke and corresponding early clinical and experimental studies. We compared the overall efficacy and assessed the impact of publication bias and study design on the efficacy. Furthermore, we estimated power and true report probability of experimental studies. RESULTS: We identified 50 phase 3 trials with 46,008 subjects, 75 early clinical trials with 12,391 subjects, and 209 experimental studies with >7,141 subjects. Three (6%) phase 3, 24 (32%) early clinical, and 143 (69.08%) experimental studies were positive. The mean treatment effect was 0.76 (95% confidence interval [CI] = 0.70-0.83) in experimental studies, 0.87 (95% CI = 0.71-1.06) in early clinical trials, and 1.00 (95% CI = 0.95-1.06) in phase 3 trials. Funnel plot asymmetry and trim-and-fill revealed a clear publication bias in experimental studies and early clinical trials. Study design and adherence to quality criteria had a considerable impact on estimated effect sizes. The mean power of experimental studies was 17%. Assuming a bias of 30% and pre-study odds of 0.5 to 0.7, this leads to a true report probability of <50%. INTERPRETATION: Pivotal study design differences between experimental studies and clinical trials, including different primary end points and time to treatment, publication bias, neglected quality criteria and low power, contribute to the stepwise efficacy decline of stroke treatments from experimental studies to phase 3 clinical trials. Even under conservative estimates, less than half of published positive experimental stroke studies are truly positive. ANN NEUROL 2020;87:40-51.
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Ensaios Clínicos como Assunto/estatística & dados numéricos , Avaliação Pré-Clínica de Medicamentos/estatística & dados numéricos , Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Humanos , Viés de Publicação , Projetos de PesquisaRESUMO
Background and Purpose- The RE-SPECT ESUS trial (Randomized, Double-Blind, Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate Versus Acetylsalicylic Acid in Patients With Embolic Stroke of Undetermined Source) tested the hypothesis that dabigatran would be superior to aspirin for the prevention of recurrent stroke in patients with embolic stroke of undetermined source. This exploratory subgroup analysis investigates the impact of age, renal function (both predefined), and dabigatran dose (post hoc) on the rates of recurrent stroke and major bleeding. Methods- RE-SPECT ESUS was a multicenter, randomized, double-blind trial of dabigatran 150 or 110 mg (for patients aged ≥75 years and/or with creatinine clearance 30 to <50 mL/minute) twice daily compared with aspirin 100 mg once daily. The primary outcome was recurrent stroke. Results- The trial, which enrolled 5390 patients from December 2014 to January 2018, did not demonstrate superiority of dabigatran versus aspirin for prevention of recurrent stroke in patients with embolic stroke of undetermined source. However, among the population qualifying for the lower dabigatran dose, the rate of recurrent stroke was reduced with dabigatran versus aspirin (7.4% versus 13.0%; hazard ratio, 0.57 [95% CI, 0.39-0.82]; interaction P=0.01). This was driven mainly by the subgroup aged ≥75 years (7.8% versus 12.4%; hazard ratio, 0.63 [95% CI, 0.43-0.94]; interaction P=0.10). Stroke rates tended to be lower with dabigatran versus aspirin with declining renal function. Risks for major bleeding were similar between treatments, irrespective of renal function, but with a trend for lower bleeding rates with dabigatran versus aspirin in older patients. Conclusions- In subgroup analyses of RE-SPECT ESUS, dabigatran reduced the rate of recurrent stroke compared with aspirin in patients qualifying for the lower dose of dabigatran. These results are hypothesis-generating. Aspirin remains the standard antithrombotic treatment for patients with embolic stroke of undetermined source. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT02239120.
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Aspirina , Dabigatrana , Fibrinolíticos , Embolia Intracraniana , Nefropatias , Acidente Vascular Cerebral , Idoso , Idoso de 80 Anos ou mais , Aspirina/administração & dosagem , Aspirina/farmacocinética , Dabigatrana/administração & dosagem , Dabigatrana/farmacocinética , Método Duplo-Cego , Feminino , Fibrinolíticos/administração & dosagem , Fibrinolíticos/farmacocinética , Humanos , Embolia Intracraniana/sangue , Embolia Intracraniana/tratamento farmacológico , Nefropatias/sangue , Nefropatias/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Recidiva , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
BACKGROUND: Detection of atrial fibrillation (AF) is one of the primary diagnostic goals for patients on a stroke unit. Physician-based manual analysis of continuous ECG monitoring is regarded as the gold standard for AF detection but requires considerable resources. Recently, automated computer-based analysis of RR intervals was established to simplify AF detection. The present prospective study analyzes both methods head to head regarding AF detection specificity, sensitivity, and overall effectiveness. METHODS: Consecutive stroke patients without history of AF or proof of AF in the admission ECG were enrolled over the period of 7 months. All patients received continuous ECG telemetry during the complete stay on the stroke unit. All ECGs underwent automated analysis by a commercially available program. Blinded to these results, all ECG tracings were also assessed manually. Sensitivity, specificity, time consumption, costs per day, and cost-effectiveness were compared. RESULTS: 216 consecutive patients were enrolled (70.7 ± 14.1 years, 56% male) and 555 analysis days compared. AF was detected by manual ECG analysis on 37 days (6.7%) and automatically on 57 days (10.3%). Specificity of the automated algorithm was 94.6% and sensitivity 78.4% (28 [5.0%] false positive and 8 [1.4%] false negative). Patients with AF were older and had more often arterial hypertension, higher NIHSS at admission, more often left atrial dilatation, and a higher CHA2DS2-VASc score. Automation significantly reduced human resources but was more expensive compared to manual analysis alone. CONCLUSION: Automatic AF detection is highly specific, but sensitivity is relatively low. Results of this study suggest that automated computer-based AF detection should be rather complementary to manual ECG analysis than replacing it.
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Algoritmos , Fibrilação Atrial/diagnóstico , Eletrocardiografia , Sistema de Condução Cardíaco/fisiopatologia , Frequência Cardíaca , Hospitalização , Processamento de Sinais Assistido por Computador , Acidente Vascular Cerebral/etiologia , Telemetria , Potenciais de Ação , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Fibrilação Atrial/fisiopatologia , Automação , Feminino , Alemanha , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Adulto JovemRESUMO
BACKGROUND: Cervical artery dissection is an important cause of stroke in the young. The etiology is still discussed controversial. The most obvious reason for a dissection of extracranial arteries is due to a trauma, eg. after car accidents or other high speed traumas such as high-velocity road traffic accidents. Besides these clear cases, chiropractic neck maneuvers represent potential reasons for vessel injuries. CASE PRESENTATION: We here report a rare case of secondary cervical artery dissection after so-called cupping therapy and a preventive treatment with a direct oral anticoagulant. CONCLUSIONS: Therapists using this technique should be aware of the potentially devastating side effects. The diagnosis of ICA dissection should be considered with any new onset of unknown neck pain or headache, specifically in combination with neurological deficits.
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Dissecação da Artéria Carótida Interna/etiologia , Ventosaterapia/efeitos adversos , Ataque Isquêmico Transitório/etiologia , Administração Oral , Anticoagulantes/administração & dosagem , Dissecação da Artéria Carótida Interna/diagnóstico por imagem , Dissecação da Artéria Carótida Interna/tratamento farmacológico , Substituição de Medicamentos , Humanos , Ataque Isquêmico Transitório/diagnóstico por imagem , Ataque Isquêmico Transitório/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/administração & dosagem , Pressão , Recidiva , Resultado do TratamentoRESUMO
OBJECTIVE: Neurological recovery after stroke mainly depends on the location of the lesion. A substantial portion of strokes affects the brainstem. However, patterns of neural plasticity following brainstem ischemia are almost unknown. METHODS: Here, we established a rat brainstem ischemia model that resembles key features of the human disease and investigated mechanisms of neural plasticity, including neurogenesis and axonal sprouting as well as secondary neurodegeneration. RESULTS: Spontaneous functional recovery was accompanied by a distinct pattern of axonal sprouting, for example, an increased bilateral fiber outgrowth from the corticorubral tract to the respective contralesional red nucleus suggesting a compensatory role of extrapyramidal pathways after damage to pyramid tracts within the brainstem. Using different markers for DNA replication, we showed that the brainstem displays a remarkable ability to undergo specific plastic cellular changes after injury, highlighting a yet unknown pattern of neurogenesis. Neural progenitor cells proliferated within the dorsal brainstem and migrated toward the lesion, whereas neurogenesis in classic neurogenic niches, the subventricular zone of the lateral ventricle and the hippocampus, remained, in contrast to what is known from hemispheric stroke, unaffected. These beneficial changes were paralleled by long-term degenerative processes, that is, corticospinal fiber loss superior to the lesion, degeneration of spinal tracts, and a decreased neuron density within the ipsilesional substantia nigra and the contralesional red nucleus that might have limited further functional recovery. INTERPRETATION: Our findings provide knowledge of elementary plastic adaptions after brainstem stroke, which is fundamental for understanding the human disease and for the development of new treatments. Ann Neurol 2018;83:1003-1015.
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Isquemia Encefálica/fisiopatologia , Tronco Encefálico/fisiopatologia , Plasticidade Neuronal/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Animais , Isquemia Encefálica/patologia , Lateralidade Funcional/fisiologia , Masculino , Córtex Motor/fisiopatologia , Neurônios/patologia , Tratos Piramidais/patologia , Ratos Wistar , Recuperação de Função Fisiológica/fisiologiaRESUMO
Rifampicin exerts significant brain protective functions in multiple experimental models. Here we summarize the underlying mechanisms of the neuroprotective and pro-cognitive effects of rifampicin that are mediated by its anti-inflammatory, anti-tau, anti-amyloid, and cholinergic effects. Beyond suggesting that rifampicin shows strong brain protective effects in preclinical models of Alzheimer's disease, we also provide substantial clinical evidence for the neuroprotective and pro-cognitive effects of rifampicin. Future neuroimaging studies combined with clinical assessment scores are the following steps to be taken in this field of research.
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Doença de Alzheimer/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Nootrópicos/farmacologia , Rifampina/farmacologia , HumanosRESUMO
BACKGROUND AND PURPOSE: Peripheral immune cell infiltration contributes to neural injury after ischemic stroke. However, in contrast to lymphocytes and neutrophils, the role of different monocyte/macrophage subsets remains to be clarified. Therefore, we evaluated the effects of selective and unselective monocyte/macrophage depletion and proinflammatory (M1-) and anti-inflammatory (M2-) macrophage transfer on the outcome after experimental cerebral ischemia. METHODS: To assess short-term effects of monocytes/macrophages in acute ischemic stroke, mice underwent transient middle cerebral artery occlusion and received either clodronate liposomes for unselective macrophage depletion, MC-21-antibody for selective depletion of proinflammatory Ly-6Chigh monocytes, or proinflammatory (M1-) or anti-inflammatory (M2-) macrophage transfer. In addition, the impact of MC-21-antibody administration and M2-macrophage transfer on long-term neural recovery was investigated after photothrombotic stroke. Neurobehavioral tests were used to analyze functional outcomes, infarct volumes were determined, and immunohistochemical analyses were performed to characterize the postischemic inflammatory reaction. RESULTS: Selective and unselective monocyte/macrophage depletion and M1- and M2-macrophage transfer did not influence tissue damage and neurobehavioral outcomes in the acute phase after middle cerebral artery occlusion. Beyond, selective depletion of Ly-6Chigh monocytes and M2-macrophage transfer did not have an impact on neural recovery after photothrombotic stroke. CONCLUSIONS: Targeting different monocyte/macrophage subsets has no impact on outcome after ischemic stroke in mice. Altogether, our study could not identify monocytes/macrophages as relevant therapeutic targets in acute ischemic stroke.
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Isquemia Encefálica/imunologia , Inflamação/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Acidente Vascular Cerebral/imunologia , Animais , Isquemia Encefálica/etiologia , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/complicações , Camundongos , Distribuição Aleatória , Acidente Vascular Cerebral/etiologiaRESUMO
BACKGROUND AND PURPOSE: Bone marrow cell (BMC)-based therapies, either the transplantation of exogenous cells or stimulation of endogenous cells by growth factors like the granulocyte colony-stimulating factor (G-CSF), are considered a promising means of treating stroke. In contrast to large preclinical evidence, however, a recent clinical stroke trial on G-CSF was neutral. We, therefore, aimed to investigate possible synergistic effects of co-administration of G-CSF and BMCs after experimental stroke in mice to enhance the efficacy compared with single treatments. METHODS: We used an animal model for experimental stroke as paradigm to study possible synergistic effects of co-administration of G-CSF and BMCs on the functional outcome and the pathophysiological mechanism. RESULTS: G-CSF treatment alone led to an improved functional outcome, a reduced infarct volume, increased blood vessel stabilization, and decreased overall inflammation. Surprisingly, the combination of G-CSF and BMCs abrogated G-CSFs' beneficial effects and resulted in increased hemorrhagic infarct transformation, altered blood-brain barrier, excessive astrogliosis, and altered immune cell polarization. These increased rates of infarct bleeding were mainly mediated by elevated matrix metalloproteinase-9-mediated blood-brain barrier breakdown in G-CSF- and BMCs-treated animals combined with an increased number of dilated and thus likely more fragile vessels in the subacute phase after cerebral ischemia. CONCLUSIONS: Our results provide new insights into both BMC-based therapies and immune cell biology and help to understand potential adverse and unexpected side effects.
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Transplante de Medula Óssea/efeitos adversos , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Hemorragia/induzido quimicamente , Imunidade Celular/imunologia , Acidente Vascular Cerebral/terapia , Animais , Células da Medula Óssea/imunologia , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Hemorragia/imunologia , Imunidade Celular/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Acidente Vascular Cerebral/imunologiaRESUMO
BACKGROUND AND PURPOSE: In spite of its high disease burden, there is no specific treatment for multi-infarct dementia. The preclinical evaluation of candidate drugs is limited because an appropriate animal model is lacking. Therefore, we aimed to evaluate whether a mouse model of recurrent photothrombotic stroke is suitable for the preclinical investigation of multi-infarct dementia. METHODS: Recurrent photothrombotic cortical infarcts were induced in 25 adult C57BL/6 mice. Twenty-five sham-operated animals served as controls. The object recognition test and the Morris water maze test were performed >6 weeks to assess cognitive deficits. Afterward, histological analyses were performed to characterize histopathologic changes associated with recurrent photothrombotic infarcts. RESULTS: After the first infarct, the object recognition test showed a trend toward an impaired formation of recognition memories (P=0.08), and the Morris Water Maze test revealed significantly impaired spatial learning and memory functions (P<0.05). After recurrent infarcts, the object recognition test showed significant recognition memory deficits (P<0.001) and the Morris water maze test demonstrated persisting spatial learning and memory deficits (P<0.05). Histological analyses revealed remote astrogliosis in the hippocampus. CONCLUSIONS: Our results show progressive cognitive deficits in a mouse model of recurrent photothrombotic stroke. The presented model resembles the clinical features of human multi-infarct dementia and enables the investigation of its pathophysiological mechanisms and the evaluation of treatment strategies.
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Comportamento Animal/fisiologia , Demência por Múltiplos Infartos/fisiopatologia , Progressão da Doença , Animais , Demência por Múltiplos Infartos/etiologia , Modelos Animais de Doenças , Trombose Intracraniana/complicações , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Reconhecimento Psicológico/fisiologia , RecidivaRESUMO
BACKGROUND AND PURPOSE: We investigated whether hyperintensities with a diameter of at least 3, 3.5, and 4 cm and visible on at least 3 slices on diffusion-weighted imaging enables patient selection with an infarct volume of ≥15 mL. METHODS: Consecutive acute stroke patients were screened for the AXIS2 trial and examined according to a standardized magnetic resonance imaging protocol in 65 sites. Diffusion-weighted lesion diameters were measured and compared with volumetric assessments. RESULTS: Out of 238 patients, 86.2% (N=206) had infarct diameter of at least 3 cm. Volumetric assessments showed infarct volume of ≥15 mL in 157 patients. A cut-off value of 3 cm led to 96.8% sensitivity and 33.3% specificity for predicting lesion volume of ≥15 mL. Analogously, a 3.5 cm cut-off led to 96.8% sensitivity and 50.6% specificity and a 4 cm cut-off led to 91.7% sensitivity and 61.7% specificity. CONCLUSIONS: Lesion diameter measures may enable multicentric patient recruitment with a prespecified minimal infarct volume. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00927836.