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Small vessel disease (SVD) is a disorder that causes vascular lesions in the entire parenchyma of the human brain. At present, it is not well understood how primary and secondary damage interact to give rise to the complex scenario of white matter (WM) and grey matter (GM) lesions. Using novel cross-sectional and longitudinal connectomic approaches, we unveil the bidirectional nature of GM and WM changes, that is, primary cortical neurodegeneration that leads to secondary alterations in vascular border zones, and WM lesions that lead to secondary neurodegeneration in cortical projecting areas. We found this GM-WM interaction to be essential for executive cognitive performance. Moreover, we also observed that the interlocked degeneration of GM and WM over time associates with prototypical expression levels of genes potentially linked to SVD. Among these connectomic-genetic intersections, we found that the Androgen Receptor (AR) gene, is a particularly central candidate gene that might confer key vulnerability for brain lesion development in SVD. In conclusion, this study advances in the understanding of the bidirectional relationships between GM and WM lesions, primary and secondary vascular neurodegeneration, and sheds light on the genetic signatures of SVD.
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Doenças de Pequenos Vasos Cerebrais , Conectoma , Substância Branca , Encéfalo , Doenças de Pequenos Vasos Cerebrais/genética , Estudos Transversais , Substância Cinzenta , Humanos , Imageamento por Ressonância MagnéticaRESUMO
Acute, painless, monocular vision loss (APMVL) usually has a vascular aetiology. We conducted a prospective observational study from 2011 to 2018 to analyse the added value of colour Doppler imaging to assess orbital vessel blood flow in the diagnosis of APMVL. The study included 67 patients (39 [58.2%] men; mean age, 65.9 years [SD 13.7]) with APMVL evaluated at the Neurosonology Laboratory within the first 5 days of symptom onset, who were classified as having either transient or persistent monocular blindness. The blood flow in the ophthalmic and central retinal arteries was assessed using colour Doppler ultrasound with a linear 7.5-MHz transducer. Thirty-three (49.3%) patients presented transient monocular blindness, with reduced blood flow in either the ophthalmic or central retinal artery. The group with persistent vision loss included 24 cases of central retinal artery occlusion (CRAO) and 10 cases of ischaemic optic neuropathy (35.8% and 14.9%, respectively, of the total sample). These patients were older and had a higher prevalence of hypertension and mild carotid atherosclerosis. Orbital colour Doppler ultrasound (OCDUS) clarified the mechanism/cause of the ischaemia in 11 (16.4%) patients and showed abnormal flow in 46 (68.7%) patients, confirming the vascular origin in 19 (57.6%) of the transient monocular blindness cases. Lower peak systolic velocity was observed in patients with CRAO (p < 0.001), and a velocity < 10 cm/s in the central retinal artery was independently associated with the diagnosis of CRAO. OCDUS can be helpful in confirming the vascular cause and identifying the aetiology of APMVL.
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Cegueira , Artéria Retiniana , Ultrassonografia Doppler em Cores , Visão Monocular , Idoso , Cegueira/diagnóstico por imagem , Cegueira/etiologia , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Isquemia/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Artéria Oftálmica/diagnóstico por imagem , Artéria Retiniana/diagnóstico por imagem , Artéria Retiniana/fisiologiaRESUMO
INTRODUCTION: Glycemic variability (GV) represents the amplitude of oscillations in glucose levels over time and is associated with higher mortality in critically ill patients. Our aim is to evaluate the impact of GV on acute ischemic stroke (IS) outcomes in humans and explore the impact of two different insulin administration routes on GV in an animal model. METHODS: This translational study consists of two studies conducted in parallel: The first study is an observational, multicenter, prospective clinical study in which 340 patients with acute IS will be subcutaneously implanted a sensor to continuously monitor blood glucose levels for 96 h. The second study is a basic experimental study using an animal model (rats) with permanent occlusion of the middle cerebral artery and induced hyperglycemia (through an intraperitoneal injection of nicotinamide and streptozotocin). The animal study will include the following 6 groups (10 animals per group): sham; hyperglycemia without IS; IS without hyperglycemia; IS and hyperglycemia without treatment; IS and hyperglycemia and intravenous insulin; and IS and hyperglycemia and subcutaneous insulin. The endpoint for the first study is mortality at 3 months, while the endpoints for the animal model study are GV, functional recovery and biomarkers. DISCUSSION: The GLIAS-III study will be the first translational approach analyzing the prognostic influence of GV, evaluated by the use of subcutaneous glucose monitors, in acute stroke. Trial registration https://www.clinicaltrials.gov (NCT04001049).
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Isquemia Encefálica , Hiperglicemia , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Glicemia , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Humanos , Hiperglicemia/complicações , Hiperglicemia/tratamento farmacológico , Insulina , Neuroglia , Prognóstico , Estudos Prospectivos , Ratos , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
Background: Frailty in older adults has been associated with reduced brain health. However, structural brain signatures of frailty remain understudied. Our aims were: (1) Explore associations between a frailty index (FI) and brain structure on magnetic resonance imaging (MRI). (2) Identify the most important FI features driving the associations. Methods: We designed a cross-sectional observational study from a population-based study (The Irish Longitudinal Study on Aging: TILDA). Participants aged ≥50 years who underwent the wave 3 MRI sub-study were included. We measured cortex, basal ganglia, and each of the Desikan-Killiany regional volumes. Age-and sex-adjusted correlations were performed with a 32-item self-reported FI that included conditions commonly tested for frailty in research and clinical settings. A graph theory analysis of the network composed by each FI item and cortex volume was performed. White matter fiber integrity was quantified using diffusion tensor imaging (DTI). Results: In 523 participants (mean age 69, 49% men), lower cortex and thalamic volumes were independently associated with higher FI. Sensory and functional difficulties, diabetes, polypharmacy, knee pain, and self-reported health were the main FI associations with cortex volume. In the network analysis, cortex volume had a modest influence within the frailty network. Regionally, higher FI was significantly associated with lower volumes in both orbitofrontal and temporal cortices. DTI analyses revealed inverse associations between the FI and the integrity of some association bundles. Conclusion: The FI used had a recognizable but subtle structural brain signature in this sample. Only some FI deficits were directly associated with cortex volume, suggesting scope for developing FIs that include metrics more specifically related with brain health in future aging neuroscience studies.
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A key hallmark of Alzheimer's disease (AD) pathology is the intracellular accumulation of tau protein in the form of neurofibrillary tangles across large-scale networks of the human brain cortex. Currently, it is still unclear how tau accumulates within specific cortical systems and whether in situ genetic traits play a role in this circuit-based propagation progression. In this study, using two independent cohorts of cognitively normal older participants, we reveal the brain network foundation of tau spreading and its association with using high-resolution transcriptomic genetic data. We observed that specific connectomic and genetic gradients exist along the tau spreading network. In particular, we identified 577 genes whose expression is associated with the spatial spreading of tau. Within this set of genes, APOE and glutamatergic synaptic genes, such as SLC1A2, play a central role. Thus, our study characterizes neurogenetic topological vulnerabilities in distinctive brain circuits of tau spreading and suggests that drug development strategies targeting the gradient expression of this set of genes should be explored to help reduce or prevent pathological tau accumulation.
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Doença de Alzheimer , Proteínas tau , Doença de Alzheimer/patologia , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Encéfalo/metabolismo , Humanos , Emaranhados Neurofibrilares/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismoRESUMO
Acute ischemic stroke is currently a major cause of disability despite improvement in recanalization therapies. Stem cells represent a promising innovative strategy focused on reduction of neurologic sequelae by enhancement of brain plasticity. We performed a phase IIa, randomized, double-blind, placebo-controlled, single-center, pilot clinical trial. Patients aged ≥60 years with moderate to severe stroke (National Institutes of Health Stroke Scale [NIHSS] 8-20) were randomized (1:1) to receive intravenous adipose tissue-derived mesenchymal stem cells (AD-MSCs) or placebo within the first 2 weeks of stroke onset. The primary outcome was safety, evaluating adverse events (AEs), neurologic and systemic complications, and tumor development. The secondary outcome evaluated treatment efficacy by measuring modified Rankin Scale (mRS), NIHSS, infarct size, and blood biomarkers. We report the final trial results after 24 months of follow-up. Recruitment began in December 2014 and stopped in December 2017 after 19 of 20 planned patients were included. Six patients did not receive study treatment: two due to technical issues and four for acquiring exclusion criteria after randomization. The final study sample was composed of 13 patients (4 receiving AD-MSCs and 9 placebo). One patient in the placebo group died within the first week after study treatment delivery due to sepsis. Two non-treatment-related serious AEs occurred in the AD-MSC group and nine in the placebo group. The total number of AEs and systemic or neurologic complications was similar between the study groups. No injection-related AEs were registered, nor tumor development. At 24 months of follow-up, patients in the AD-MSC group showed a nonsignificantly lower median NIHSS score (interquartile range, 3 [3-5.5] vs 7 [0-8]). Neither treatment group had differences in mRS scores throughout follow-up visits up to month 24. Therefore, intravenous treatment with AD-MSCs within the first 2 weeks from ischemic stroke was safe at 24 months of follow-up.
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Isquemia Encefálica , Transplante de Células-Tronco Hematopoéticas , AVC Isquêmico , Células-Tronco Mesenquimais , Acidente Vascular Cerebral , Isquemia Encefálica/tratamento farmacológico , Método Duplo-Cego , Humanos , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do TratamentoRESUMO
Background: Timely coordination between stroke team members is of relevance for stroke code management. We explore the feasibility and potential utility of a smartphone application for clinical and neuroimaging data sharing for improving workflow metrics of stroke code pathways, and professionals' opinions about its use. Methods: We performed an observational pilot study including stroke code activations at La Paz University Hospital in Madrid, from June 2019 to March 2020. Patients were classified according to the activation or not of the JOIN app by the attending physician. Clinical data and time-to-procedures were retrieved from the app or from the hospital records and the Madrid regional stroke registry as appropriate and compared between both groups. An anonymous survey collected professionals' opinions about the app and its use. Results: A total of 282 stroke code activations were registered. The JOIN app was activated in 111 (39%) cases. They had a significant reduction in imaging-to-thrombolysis (31 vs 20 min, p = .026) and in door-to-thrombolysis times (51 vs 36 min, p = .004), with more patients achieving a door-to-needle time below 45 min (68.8% vs 37.8%, p = .016). About 50% of the users found the app useful for facilitating the diagnosis and decision-making; interoperability with clinical files was considered an opportunity for improvement. Conclusions: This pilot study suggests that JOIN helps improve and document workflow metrics in acute stroke management in a comprehensive stroke centre. These results support testing JOIN in a prospective randomised study to confirm its usefulness and the general applicability of the results.
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BACKGROUND: Communication is one of the most important predictors of social reintegration after stroke. Approximately 15-42% of stroke survivors experience post-stroke aphasia. Helping people recover from aphasia is one of the research priorities after a stroke. Our aim is to develop and validate a new therapy integrating dubbing techniques to improve functional communication. METHODS: The research project is structured as three work packages (WP). WP1: development of the dubbed language cinema-based therapy: Two research assistants (a speech therapist and a dubbing actor) will select the clips, mute specific words/sentences in progressive speech difficulty, and guide patients to dub them across sessions. Words to be dubbed will be those considered to be functionally meaningful by a representative sample of aphasic patients and relatives through an online survey. WP2: a randomized, crossover, interventional pilot study with the inclusion of 54 patients with post-stroke non-fluent aphasia. Patients will be treated individually in 40-min sessions twice per week for 8 weeks. Primary outcomes will be significant pre/post differences in scores in the Communicative Activity Log (CAL) questionnaire and Boston Diagnostic Aphasia Examination (BDAE) administered by a psychologist blinded to the patients' clinical characteristics. SECONDARY OUTCOMES: General Health Questionnaire (GHQ)-12, Stroke Aphasia Quality of Life Scale (SAQOL-39), Western Aphasia Battery Revised (WAB-R), and the Stroke Aphasic Depression Questionnaire (SADQ10). WP3: educational activities and dissemination of results. WP3 includes educational activities to improve public knowledge of aphasia and dissemination of the results, with the participation of the Spanish patients' association Afasia Activa. DISCUSSION: This pilot clinical trial will explore the efficacy of a new therapeutic tool based on dubbing techniques and computer technology to improve functional communication of patients suffering from post-stroke aphasia with the use of standardized test assessment. TRIAL REGISTRATION: ClinicalTrials.gov NCT04289493 . Registered on 28 February 2020.
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Afasia , Reabilitação do Acidente Vascular Cerebral , Afasia/diagnóstico , Afasia/etiologia , Afasia/terapia , Humanos , Idioma , Filmes Cinematográficos , Projetos Piloto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , FonoterapiaRESUMO
Introduction: The degree of disability after stroke needs to be objectively measured to implement adequate rehabilitation programs. Here, we evaluate the feasibility of a custom-built software to assess motor status after stroke. Methods: This is a prospective, case-control pilot study comparing stroke patients with healthy volunteers. A workout evaluation that included trunk and upper limb movement was captured with Kinect® and kinematic metrics were extracted with Akira®. Trunk and joint angles were analyzed and compared between cases and controls. Patients were evaluated within the first week from stroke onset using the National Institutes of Health Stroke Scale (NIHSS), Fulg-Meyer Assessment (FMA), and modified Rankin Scale (mRS) scales; the relationship with kinematic measurements was explored. Results: Thirty-seven patients and 33 controls were evaluated. Median (IQR) NIHSS of cases was 2 (0-4). The kinematic metrics that showed better discriminatory capacity were body sway during walking (less in cases than in controls, p = 0.01) and the drift in the forearm-trunk angle during shoulder abduction in supination (greater in cases than in controls, p = 0.01). The body sway during walking was moderately correlated with NIHSS score (Rho = -0.39; p = 0.01) but better correlated with mRS score (Rho = -0.52; p < 0.001) and was associated with the absence of disability (mRS 0-1) (OR = 0.64; p = 0.02). The drift in the forearm-trunk angle in supination was associated with the presence of disability (mRS >1) (OR = 1.27; p = 0.04). Conclusion: We present a new software that detects even mild motor impairment in stroke patients underestimated by clinical scales but with an impact on patient functionality.
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Background and Objective: Oral anticoagulation (OAC) for secondary stroke prevention is recommended in atrial fibrillation (AF) and other sources of cardioembolic stroke. Our objectives were to explore the differences in ischemic and hemorrhagic events when using OAC for secondary stroke prevention according to the type of anticoagulant treatment and to analyze the number and reasons for OAC switches during long-term follow-up. Methods: Ischemic stroke (IS) patients who were discharged on OAC for secondary stroke prevention from January 2014 to October 2017 were recruited in a prospective, multicenter, hospital-based registry. Follow-up at 3 months was scheduled at the outpatient clinic with subsequent annual phone interviews for 3 years. Patients were classified into three study groups according to OAC at discharge: Vitamin K antagonist (VKA), Factor Xa inhibitor (FXa), or direct thrombin inhibitor (DTI). We compared stroke recurrences, intracranial hemorrhage, major bleeding, and all-cause mortality during the follow-up. We recorded any switches in OAC and the main reasons for the change. Results: A total of 241 patients were included. An anticoagulant was indicated in the presence of a source of cardioembolic stroke in 240 patients (99.6%) and lupus plus antiphospholipid syndrome in one patient. Up to 86 patients (35.6%) were on OAC before the index stroke; in 71 (82.5%) of them, this was VKA. At hospital discharge, 105 were treated with FXa (43.8%), 96 with VKA (39.6%), and 40 with DTI (16.6%). The cumulative incidences at 3 years were 17% for stroke recurrence, 1.6% for intracranial hemorrhage, 4.9% for major hemorrhage, and 22.8% for all-cause mortality, with no differences among the OAC groups in any outcomes. During the follow-up, 40 OAC switches were recorded (63% of them to FXa), mostly due to stroke recurrence. Conclusion: Long-term OAC in secondary stroke prevention is associated with a lower frequency of bleeding complications than stroke recurrences. No differences between anticoagulant drugs were found in any of the analyzed outcomes. The main cause for OAC switch during follow-up was stroke recurrence.
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The term cryptogenic stroke refers to a stroke for which there is no specific attributable cause after a comprehensive evaluation. However, there are differences between the diagnostic criteria of etiological classifications used in clinical practice. An improvement in diagnostic tools such advances in monitoring for atrial fibrillation, advances in vascular imaging and evidence regarding the implication of patent foramen oval on the risk of stroke specially in young patients are reducing the proportion of stroke patients without etiological diagnosis. We carried out a critical review of the current concept of cryptogenic stroke, as a non-diagnosis, avoiding the simplification of it and reviewing the different entities that could fall under this diagnosis and reviewing the different entities that could fall under this diagnosis; and therefore avoid the same treatment for differents entities with uncertains results.