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1.
Stroke ; 54(10): 2676-2687, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37646161

RESUMO

Ischemic stroke is a leading cause of disability and there is a paucity of therapeutic strategies that promote functional recovery after stroke. Transcutaneous vagus nerve stimulation (tVNS) has shown promising evidence as a tool to reduce infarct size in animal models of hyperacute stroke. In chronic stroke, tVNS paired with limb movements has been shown to enhance neurological recovery. In this review, we summarize the current evidence for tVNS in preclinical models and clinical trials in humans. We highlight the mechanistic pathways involved in the beneficial effects of tVNS. We critically evaluate the current gaps in knowledge and recommend the key areas of research required to translate tVNS into clinical practice in acute and chronic stroke.


Assuntos
AVC Isquêmico , Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Animais , Humanos , Nervo Vago/fisiologia
2.
Lancet ; 397(10284): 1545-1553, 2021 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-33894832

RESUMO

BACKGROUND: Long-term loss of arm function after ischaemic stroke is common and might be improved by vagus nerve stimulation paired with rehabilitation. We aimed to determine whether this strategy is a safe and effective treatment for improving arm function after stroke. METHODS: In this pivotal, randomised, triple-blind, sham-controlled trial, done in 19 stroke rehabilitation services in the UK and the USA, participants with moderate-to-severe arm weakness, at least 9 months after ischaemic stroke, were randomly assigned (1:1) to either rehabilitation paired with active vagus nerve stimulation (VNS group) or rehabilitation paired with sham stimulation (control group). Randomisation was done by ResearchPoint Global (Austin, TX, USA) using SAS PROC PLAN (SAS Institute Software, Cary, NC, USA), with stratification by region (USA vs UK), age (≤30 years vs >30 years), and baseline Fugl-Meyer Assessment-Upper Extremity (FMA-UE) score (20-35 vs 36-50). Participants, outcomes assessors, and treating therapists were masked to group assignment. All participants were implanted with a vagus nerve stimulation device. The VNS group received 0·8 mA, 100 µs, 30 Hz stimulation pulses, lasting 0·5 s. The control group received 0 mA pulses. Participants received 6 weeks of in-clinic therapy (three times per week; total of 18 sessions) followed by a home exercise programme. The primary outcome was the change in impairment measured by the FMA-UE score on the first day after completion of in-clinic therapy. FMA-UE response rates were also assessed at 90 days after in-clinic therapy (secondary endpoint). All analyses were by intention to treat. This trial is registered at ClinicalTrials.gov, NCT03131960. FINDINGS: Between Oct 2, 2017, and Sept 12, 2019, 108 participants were randomly assigned to treatment (53 to the VNS group and 55 to the control group). 106 completed the study (one patient for each group did not complete the study). On the first day after completion of in-clinic therapy, the mean FMA-UE score increased by 5·0 points (SD 4·4) in the VNS group and by 2·4 points (3·8) in the control group (between group difference 2·6, 95% CI 1·0-4·2, p=0·0014). 90 days after in-clinic therapy, a clinically meaningful response on the FMA-UE score was achieved in 23 (47%) of 53 patients in the VNS group versus 13 (24%) of 55 patients in the control group (between group difference 24%, 6-41; p=0·0098). There was one serious adverse event related to surgery (vocal cord paresis) in the control group. INTERPRETATION: Vagus nerve stimulation paired with rehabilitation is a novel potential treatment option for people with long-term moderate-to-severe arm impairment after ischaemic stroke. FUNDING: MicroTransponder.


Assuntos
Neuroestimuladores Implantáveis/efeitos adversos , AVC Isquêmico/complicações , Reabilitação do Acidente Vascular Cerebral/métodos , Extremidade Superior/fisiopatologia , Estimulação do Nervo Vago/instrumentação , Idoso , Estudos de Casos e Controles , Terapia Combinada/métodos , Terapia por Exercício/métodos , Feminino , Humanos , AVC Isquêmico/reabilitação , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Paresia/etiologia , Recuperação de Função Fisiológica/fisiologia , Resultado do Tratamento , Paralisia das Pregas Vocais/epidemiologia
3.
Ann Pharmacother ; 56(10): 1159-1173, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35094598

RESUMO

OBJECTIVE: A literature review of antiplatelet agents for primary and secondary stroke prevention, including mechanism of action, cost, and reasons for lack of benefit. DATA SOURCES: Articles were gathered from MEDLINE, Cochrane Reviews, and PubMed databases (1980-2021). Abstracts from scientific meetings were considered. Search terms included ischemic stroke, aspirin, clopidogrel, dipyridamole, ticagrelor, cilostazol, prasugrel, glycoprotein IIb/IIIa inhibitors. STUDY SELECTION AND DATA EXTRACTION: English-language original and review articles were evaluated. Guidelines from multiple countries were reviewed. Articles were evaluated independently by 2 authors. DATA SYNTHESIS: An abundance of evidence supports aspirin and clopidogrel use for secondary stroke prevention. In the acute phase (first 21 days postinitial stroke), these medications have higher efficacy for preventing further stroke when combined, but long-term combination therapy is associated with higher hemorrhage rates. Antiplatelet treatment failure is influenced by poor adherence and genetic polymorphisms. Antiplatelet agents such as cilostazol may provide extra benefit over clopidogrel and aspirin, in certain racial groups, but further research in more diverse ethnic populations is needed. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: This review presents the data available on the use of different antiplatelet agents poststroke. Dual therapy, recurrence after initiation of secondary preventative therapy, and areas for future research are discussed. CONCLUSIONS: Although good evidence exists for the use of certain antiplatelet agents postischemic stroke, there are considerable opportunities for future research to investigate personalized therapies. These include screening patients for platelet polymorphisms that confer antiplatelet resistance and for randomized trials including more racially diverse populations.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Aspirina , Cilostazol/uso terapêutico , Clopidogrel , Quimioterapia Combinada , Humanos , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/induzido quimicamente , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle
4.
Stroke ; 52(7): 2445-2455, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34039033

RESUMO

Exercise interventions have been shown to help physical fitness, walking, and balance after stroke, but data are lacking on whether such interventions lead to improvements in health-related quality of life (HRQoL). In this systematic review and meta-analysis, 30 randomized controlled trials (n=1836 patients) were found from PubMed, OVID MEDLINE, Web of Science, CINAHL, SCOPUS, The Cochrane Library, and TRIP databases when searched from 1966 to February 2020 that examine the effects of exercise interventions on HRQoL after stroke or transient ischemic attack. Exercise interventions resulted in small to moderate beneficial effects on HRQoL at intervention end (standardized mean difference, -0.23 [95% CI, -0.40 to -0.07]) that appeared to diminish at longer-term follow-up (standardized mean difference, -0.11 [95% CI, -0.26 to 0.04]). Exercise was associated with moderate improvements in physical health (standardized mean difference, -0.33 [95% CI, -0.61 to -0.04]) and mental health (standardized mean difference, -0.29 [95% CI, -0.49 to -0.09]) domains of HRQoL while effects on social or cognitive composites showed little difference. Interventions that were initiated within 6 months, lasted at least 12 weeks in duration, involved at least 150 minutes per week, and included resistance training appeared most effective. Exercise can lead to moderate beneficial effects on HRQoL and should be considered an integral part of stroke rehabilitation.


Assuntos
Exercício Físico/fisiologia , Ataque Isquêmico Transitório/terapia , Qualidade de Vida , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Exercício Físico/psicologia , Terapia por Exercício/métodos , Terapia por Exercício/psicologia , Humanos , Ataque Isquêmico Transitório/psicologia , Aptidão Física/fisiologia , Qualidade de Vida/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Acidente Vascular Cerebral/psicologia , Reabilitação do Acidente Vascular Cerebral/psicologia , Resultado do Tratamento
5.
Int J Mol Sci ; 21(9)2020 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-32357505

RESUMO

l-carnosine is an attractive therapeutic agent for acute ischemic stroke based on its robust preclinical cerebroprotective properties and wide therapeutic time window. However, large doses are needed for efficacy because carnosine is rapidly degraded in serum by carnosinases. The need for large doses could be particularly problematic when translating to human studies, as humans have much higher levels of serum carnosinases. We hypothesized that d-carnosine, which is not a substrate for carnosinases, may have a better pharmacological profile and may be more efficacious at lower doses than l-carnosine. To test our hypothesis, we explored the comparative pharmacokinetics and neuroprotective properties of d- and L-carnosine in acute ischaemic stroke in mice. We initially investigated the pharmacokinetics of d- and L-carnosine in serum and brain after intravenous (IV) injection in mice. We then investigated the comparative efficacy of d- and l-carnosine in a mouse model of transient focal cerebral ischemia followed by in vitro testing against excitotoxicity and free radical generation using primary neuronal cultures. The pharmacokinetics of d- and l-carnosine were similar in serum and brain after IV injection in mice. Both d- and l-carnosine exhibited similar efficacy against mouse focal cerebral ischemia. In vitro studies in neurons showed protection against excitotoxicity and the accumulation of free radicals. d- and l-carnosine exhibit similar pharmacokinetics and have similar efficacy against experimental stroke in mice. Since humans have far higher levels of carnosinases, d-carnosine may have more favorable pharmacokinetics in future human studies.


Assuntos
Carnosina/administração & dosagem , AVC Isquêmico/tratamento farmacológico , Neurônios/citologia , Fármacos Neuroprotetores/administração & dosagem , Animais , Química Encefálica , Carnosina/química , Carnosina/farmacocinética , Células Cultivadas , Modelos Animais de Doenças , Humanos , Injeções Intravenosas , AVC Isquêmico/sangue , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacocinética , Cultura Primária de Células
6.
Br J Sports Med ; 53(24): 1515-1525, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29743171

RESUMO

OBJECTIVE: Secondary vascular risk reduction is critical to preventing recurrent stroke. We aimed to evaluate the effect of exercise interventions on vascular risk factors and recurrent ischaemic events after stroke or transient ischaemic attack (TIA). DESIGN: Intervention systematic review and meta-analysis. DATA SOURCES: OVID MEDLINE, PubMed, The Cochrane Library, Web of Science, The National Institute for Health and Care Excellence, TRIP Database, CINAHL, PsycINFO, SCOPUS, UK Clinical Trials Gateway and the China National Knowledge Infrastructure were searched from 1966 to October 2017. ELIGIBILITY CRITERIA: Randomised controlled trials evaluating aerobic or resistance exercise interventions on vascular risk factors and recurrent ischaemic events among patients with stroke or TIA, compared with control. RESULTS: Twenty studies (n=1031) were included. Exercise interventions resulted in significant reductions in systolic blood pressure (SBP) -4.30 mm Hg (95% CI -6.77 to -1.83) and diastolic blood pressure -2.58 mm Hg (95% CI -4.7 to -0.46) compared with control. Reduction in SBP was most pronounced among studies initiating exercise within 6 months of stroke or TIA (-8.46 mm Hg, 95% CI -12.18 to -4.75 vs -2.33 mm Hg, 95% CI -3.94 to -0.72), and in those incorporating an educational component (-7.81 mm Hg, 95% CI -14.34 to -1.28 vs -2.78 mm Hg, 95% CI -4.33 to -1.23). Exercise was also associated with reductions in total cholesterol (-0.27 mmol/L, 95% CI -0.54 to 0.00), but not fasting glucose or body mass index. One trial reported reductions in secondary vascular events with exercise, but was insufficiently powered. SUMMARY: Exercise interventions can result in clinically meaningful blood pressure reductions, particularly if initiated early and alongside education.


Assuntos
Pressão Sanguínea/fisiologia , Terapia por Exercício/métodos , Ataque Isquêmico Transitório/prevenção & controle , Ataque Isquêmico Transitório/fisiopatologia , Prevenção Secundária , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/fisiopatologia , Glicemia/metabolismo , Índice de Massa Corporal , Colesterol/sangue , Exercício Físico , Humanos , Ataque Isquêmico Transitório/sangue , Fatores de Risco , Acidente Vascular Cerebral/sangue
7.
J Stroke Cerebrovasc Dis ; 28(12): 104348, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31570261

RESUMO

BACKGROUND: Sensory impairment is associated with reduced functional recovery in stroke survivors. Invasive vagus nerve stimulation (VNS) paired with rehabilitative interventions improves motor recovery in chronic stroke. Noninvasive approaches, for example, transcutaneous auricular VNS (taVNS) are safe, well-tolerated and may also improve motor function in those with residual weakness. We report the impact of taVNS paired with a motor intervention, repetitive task practice, on sensory recovery in a cohort of patients with chronic stroke. METHODS: Twelve participants who were more than 3 months postischemic stroke with residual upper limb weakness received 18 × 1 hour sessions over 6 weeks with an average of at least 300 repetitions of functional arm movements per session concurrently with taVNS at maximum tolerated intensity. Light touch and proprioception were scored as part of the Upper Limb Fugl-Meyer (UFM) assessment at baseline and postintervention (score range for sensation 0-12). RESULTS: Eleven participants (92%) had sensory impairment at baseline of whom 7 (64%) regained some sensation (proprioception n = 6 participants, light touch n = 2, both modalities n = 1) postintervention. The maximal increase in UFM sensation score (3 points) was seen in the patient with the greatest improvement in motor function. CONCLUSIONS: taVNS paired with motor rehabilitation may improve sensory recovery in chronic stroke patients. The relative contribution of motor and sensory rehabilitation to overall functional recovery in chronic stroke needs further characterization in a larger, phase 2 study.


Assuntos
Terapia por Exercício , Atividade Motora , Sensação , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Estimulação Elétrica Nervosa Transcutânea , Extremidade Superior/inervação , Estimulação do Nervo Vago , Idoso , Doença Crônica , Orelha , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Plasticidade Neuronal , Propriocepção , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Tato , Percepção do Tato , Resultado do Tratamento
8.
J Stroke Cerebrovasc Dis ; 27(7): 1998-2005, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29580658

RESUMO

BACKGROUND: Invasive vagus nerve stimulation (VNS) has the potential to enhance the effects of physiotherapy for upper limb motor recovery after stroke. Noninvasive, transcutaneous auricular branch VNS (taVNS) may have similar benefits, but this has not been evaluated in stroke recovery. We sought to determine the feasibility of taVNS delivered alongside upper limb repetitive task-specific practice after stroke and its effects on a range of outcome measures evaluating limb function. MATERIALS AND METHODS: Thirteen participants at more than 3 months postischemic stroke with residual upper limb dysfunction were recruited from the community of Sheffield, United Kingdom (October-December 2016). Participants underwent 18 × 1-hour sessions over 6 weeks in which they made 30-50 repetitions of 8-10 arm movements concurrently with taVNS (NEMOS; Cerbomed, Erlangen, Germany, 25 Hz, .1-millisecond pulse width) at maximum tolerated intensity (mA). An electrocardiogram and rehabilitation outcome scores were obtained at each visit. Qualitative interviews determined the acceptability of taVNS to participants. RESULTS: Median time after stroke was 1.16 years, and baseline median/interquartile range upper limb Fugl-Meyer (UFM) score was 63 (54.5-99.5). Participants attended 92% of the planned treatment sessions. Three participants reported side effects, mainly fatigue, but all performed mean of more than 300 arm repetitions per session with no serious adverse events. There was a significant change in the UFM score with a mean increase per participant of 17.1 points (standard deviation 7.8). CONCLUSION: taVNS is feasible and well-tolerated alongside upper limb repetitive movements in poststroke rehabilitation. The motor improvements observed justify a phase 2 trial in patients with residual arm weakness.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Extremidade Superior , Estimulação do Nervo Vago , Idoso , Terapia Combinada , Orelha , Estudos de Viabilidade , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Paresia/etiologia , Paresia/fisiopatologia , Paresia/terapia , Satisfação do Paciente , Projetos Piloto , Pesquisa Qualitativa , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Reabilitação do Acidente Vascular Cerebral/efeitos adversos , Resultado do Tratamento , Extremidade Superior/fisiopatologia , Estimulação do Nervo Vago/efeitos adversos , Estimulação do Nervo Vago/métodos
10.
Stroke ; 46(1): 182-189, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25477221

RESUMO

BACKGROUND AND PURPOSE: For symptomatic patients with carotid artery stenosis, the risk benefit for surgical intervention may vary among patient groups. Various modalities of plaque imaging have been promoted as potential tools for additional risk stratification, particularly in patients with moderate stenosis. However, it remains uncertain to what extent carotid plaque components predict risk of future ipsilateral ischemic stroke. METHODS: In 2 large atherosclerotic carotid plaque biobank studies, we related histological characteristics of 1640 carotid plaques with a validated risk model for the prediction of individual 1- and 5-year stroke risk. RESULTS: No significant heterogeneity between the studies was found. Predicted 5-year stroke risk (top versus bottom quartile) was related to plaque thrombus (odds ratio, 1.42; 95% confidence interval, 1.11-1.89; P=0.02), fibrous content (0.65; 0.49-0.87; P=0.004), macrophage infiltration (1.41; 1.05-1.90; P=0.02), high microvessel density (1.49; 1.05-2.11; P=0.03), and overall plaque instability (1.40; 1.05-1.87; P=0.02). This association was not observed for cap thickness, calcification, intraplaque hemorrhage, or lymphocyte infiltration. Plaques removed within 30 days of most recent symptomatic event were most strongly correlated with predicted stroke risk. CONCLUSIONS: Features of the vulnerable carotid plaque, including plaque thrombus, low fibrous content, macrophage infiltration, and microvessel density, correlate with predicted stroke risk. This study provides a basis for plaque imaging studies focused on stroke risk stratification.


Assuntos
Isquemia Encefálica/etiologia , Estenose das Carótidas/patologia , Macrófagos/patologia , Neovascularização Patológica/patologia , Placa Aterosclerótica/patologia , Acidente Vascular Cerebral/etiologia , Trombose/patologia , Idoso , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/patologia , Estenose das Carótidas/complicações , Feminino , Hemorragia/complicações , Hemorragia/patologia , Humanos , Linfócitos/patologia , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Neovascularização Patológica/complicações , Placa Aterosclerótica/complicações , Fatores de Risco , Trombose/complicações , Calcificação Vascular/complicações , Calcificação Vascular/patologia
11.
Int J Mol Sci ; 16(10): 24048-58, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26473839

RESUMO

Clinical trials are the backbone of medical research, and are often the last step in the development of new therapies for use in patients. Prior to human testing, however, preclinical studies using animal subjects are usually performed in order to provide initial data on the safety and effectiveness of prospective treatments. These studies can be costly and time consuming, and may also raise concerns about the ethical treatment of animals when potentially harmful procedures are involved. Adaptive design is a process by which the methods used in a study may be altered while it is being conducted in response to preliminary data or other new information. Adaptive design has been shown to be useful in reducing the time and costs associated with clinical trials, and may provide similar benefits in preclinical animal studies. The purpose of this review is to summarize various aspects of adaptive design and evaluate its potential for use in preclinical research.


Assuntos
Pesquisa Biomédica/métodos , Ensaios Clínicos como Assunto/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Projetos de Pesquisa , Animais
12.
Stroke ; 44(3): 734-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23362077

RESUMO

BACKGROUND AND PURPOSE: Patients with carotid artery stenosis and ocular ischemic events have a much lower risk of future ipsilateral ischemic stroke on medical treatment and lower procedural risks for endarterectomy and stenting than patients with cerebral ischemic events, and are closer in risk to patients with asymptomatic stenosis. The reasons for this difference in prognosis are not fully understood, but may reflect differences in carotid plaque pathology. METHODS: In consecutive patients undergoing carotid endarterectomy for recently symptomatic stenosis (Oxford Plaque Study, Athero-Express Study), we compared carotid plaque histology (using validated semiquantitative scales) in those who had cerebral events within the last 6 months (n=1317) versus those with ocular events only (n=323). RESULTS: Compared with plaques from patients with ocular events only, those from patients with cerebral events had significantly more large lipid core (odds ratio [OR], 1.38; 95% confidence interval [CI], 1.05-1.82; P=0.02), inflammation (OR, 1.32; 95% CI, 1.02-1.72; P=0.04) and overall plaque instability (OR, 1.37; 95% CI, 1.05-1.80; P=0.02), and less fibrous content (OR, 0.71; 95% CI, 0.54-0.92; P=0.01), and calcification (OR, 0.70; 95% CI, 0.54-0.91; P=0.008). The overall number of histological features known to be associated with vulnerable plaque was greater in patients with cerebral events than in those with ocular events (P=0.002). CONCLUSIONS: Carotid plaques from patients undergoing endarterectomy for previous ocular ischemic events have fewer vulnerable plaque features than those from patients with recent cerebral ischemic events, possibly explaining some of the differences in risk of stroke between these groups.


Assuntos
Isquemia Encefálica/patologia , Estenose das Carótidas/patologia , Neuropatia Óptica Isquêmica/patologia , Idoso , Isquemia Encefálica/epidemiologia , Estenose das Carótidas/complicações , Estenose das Carótidas/terapia , Endarterectomia das Carótidas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuropatia Óptica Isquêmica/epidemiologia , Fatores de Risco , Stents
13.
Neurorehabil Neural Repair ; 37(6): 367-373, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36226541

RESUMO

BACKGROUND: Vagus Nerve Stimulation (VNS) paired with rehabilitation improved upper extremity impairment and function in a recent pivotal, randomized, triple-blind, sham-controlled trial in people with chronic arm weakness after stroke. OBJECTIVE: We aimed to determine whether treatment effects varied across candidate subgroups, such as younger age or less injury. METHODS: Participants were randomized to receive rehabilitation paired with active VNS or rehabilitation paired with sham stimulation (Control). The primary outcome was the change in impairment measured by the Fugl-Meyer Assessment Upper Extremity (FMA-UE) score on the first day after completion of 6-weeks in-clinic therapy. We explored the effect of VNS treatment by sex, age (≥62 years), time from stroke (>2 years), severity (baseline FMA-UE score >34), paretic side of body, country of enrollment (USA vs UK) and presence of cortical involvement of the index infarction. We assessed whether there was any interaction with treatment. FINDINGS: The primary outcome increased by 5.0 points (SD 4.4) in the VNS group and by 2.4 points (SD 3.8) in the Control group (P = .001, between group difference 2.6, 95% CI 1.03-4.2). The between group difference was similar across all subgroups and there were no significant treatment interactions. There was no important difference in rates of adverse events across subgroups. CONCLUSION: The response was similar across subgroups examined. The findings suggest that the effects of paired VNS observed in the VNS-REHAB trial are likely to be consistent in wide range of stroke survivors with moderate to severe upper extremity impairment.


Assuntos
AVC Isquêmico , Transtornos Motores , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Estimulação do Nervo Vago , Humanos , Pessoa de Meia-Idade , Transtornos Motores/etiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Extremidade Superior , Recuperação de Função Fisiológica , Resultado do Tratamento
14.
Auton Neurosci ; 237: 102909, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34861612

RESUMO

Stroke is one of the leading causes of death and disability globally. A significant proportion of stroke survivors are left with long term neurological deficits that have a detrimental effect on personal wellbeing and wider socioeconomic impacts. As such, there is an unmet need for novel therapies that improve neurological recovery after stroke. Invasive vagus nerve stimulation (VNS) paired with rehabilitation has been shown to improve upper limb motor function in chronic stroke. However, invasive VNS requires a surgical procedure and therefore may not be suitable for all stroke patients. Non-invasive, transcutaneous VNS (tVNS) via auricular vagus nerve stimulation in the ear (taVNS) and cervical vagus nerve stimulation in the neck (tcVNS) have been shown to activate similar vagal nerve projections in the central nervous system to invasive VNS. A number of pre-clinical studies indicate that tVNS delivered in acute middle cerebral artery occlusion reduces infarct size through anti-inflammatory effects, reduced excitotoxicity and increased blood-brain barrier integrity. Longer term effects of tVNS in stroke that may mediate neuroplasticity include microglial polarisation, angiogenesis and neurogenesis. Pilot clinical trials of taVNS indicate that taVNS paired with rehabilitation may improve upper limb motor and sensory function in patients with chronic stroke. In this review, we summarise and critically appraise the current pre-clinical and clinical evidence, outline the major ongoing clinical trials and detail the challenges and future directions regarding tVNS in acute and chronic stroke.


Assuntos
Acidente Vascular Cerebral , Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Humanos , Sensação , Acidente Vascular Cerebral/terapia , Nervo Vago
15.
Front Cardiovasc Med ; 9: 948461, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36158793

RESUMO

Tribbles 3 (TRIB3) modulates lipid and glucose metabolism, macrophage lipid uptake, with a gain-of-function variant associated with increased cardiovascular risk. Here we set out to examine the role of this pseudokinase in atherosclerotic plaque development. Human endarterectomy atherosclerotic tissue specimens analysed by immunofluorescence showed upregulated TRIB3 in unstable plaques and an enrichment in unstable regions of stable plaques. Atherosclerosis was induced in full body Trib3KO and Trib3WT littermate mice by injecting mPCSK9 expressing adeno-associated virus and western diet feeding for 12 weeks. Trib3KO mice showed expanded visceral adipose depot while circulatory lipid levels remained unaltered compared to wildtype mice. Trib3KO mice aortae showed a reduced plaque development and improved plaque stability, with increased fibrous cap thickness and collagen content, which was accompanied by increased macrophage content. Analysis of both mouse and human macrophages with reduced TRIB3 expression showed elongated morphology, increased actin expression and altered regulation of genes involved in extracellular matrix remodelling. In summary, TRIB3 controls plaque development and may be atherogenic in vivo. Loss of TRIB3 increases fibrous cap thickness via altered metalloproteinase expression in macrophages, thus inhibiting collagen and elastic fibre degradation, suggesting a role for TRIB3 in the formation of unstable plaques.

16.
Stroke Vasc Neurol ; 6(2): 298-309, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33903181

RESUMO

Remote ischaemic conditioning (RIC) refers to a process whereby periods of intermittent ischaemia, typically via the cyclical application of a blood pressure cuff to a limb at above systolic pressure, confers systemic protection against ischaemia in spatially distinct vascular territories. The mechanisms underlying this have not been characterised fully but have been shown to involve neural, hormonal and systemic inflammatory signalling cascades. Preclinical and early clinical studies have been promising and suggest beneficial effects of RIC in acute ischaemic stroke, symptomatic intracranial stenosis and vascular cognitive impairment. Through systematic searches of several clinical trials databases we identified 48 active clinical trials of RIC in ischaemic stroke, intracerebral haemorrhage and subarachnoid haemorrhage. We summarise the different RIC protocols and outcome measures studied in ongoing clinical trials and highlight which studies are most likely to elucidate the underlying biological mechanisms of RIC and characterise its efficacy in the near future. We discuss the uncertainties of RIC including the optimal frequency and duration of therapy, target patient groups, cost-effectiveness, the confounding impact of medications and the absence of a clinically meaningful biomarker of the conditioning response. With several large clinical trials of RIC expected to report their outcomes within the next 2 years, this review aims to highlight the most important studies and unanswered questions that will need to be addressed before this potentially widely accessible and low-cost intervention can be used in clinical practice.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Hemorragia Subaracnóidea , Isquemia Encefálica/prevenção & controle , Isquemia Encefálica/terapia , Humanos , Isquemia , AVC Isquêmico/diagnóstico , AVC Isquêmico/terapia , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/terapia
17.
Stroke ; 41(10): 2288-94, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20814007

RESUMO

BACKGROUND AND PURPOSE: Rates of incident and recurrent cardiovascular events rise steadily with age, due partly to more extensive atherosclerotic burden. However, in patients with similarly severe symptomatic carotid stenosis, increasing age is associated with a greater risk of ipsilateral ischemic stroke. This effect may be due to age-related differences in the pathology of symptomatic carotid plaques. However, previous studies of plaque pathology in relation to age have not accounted for potential confounders, particularly smoking, which is often less prevalent in the elderly population undergoing endarterectomy. Method-We related patient age (<55, 55 to 64, 65 to 74, 75+ years) and smoking habit (never, exsmoker, recent smoker, and current smoker; and number of cigarettes smoked per day) to detailed histological assessments of 526 carotid plaques from consecutive patients undergoing carotid endarterectomy for symptomatic carotid stenosis. RESULTS: Three hundred seventy-nine (72.1%) patients were male (mean/SD age 66.6/8.7). Current/recent smokers were on average 7 years younger at carotid endarterectomy than ex-/never smokers (P<0.001), and age at carotid endarterectomy decreased with increasing number of cigarettes smoked per day (P trend=0.005). Plaques from current/recent smokers had a lower prevalence of intraplaque hemorrhage (P -trend=0.01), but histology was otherwise similar to that in ex-/never smokers, and both groups showed similar changes with age. With increasing age, plaque calcification and large lipid core increased (P<0.001 and P=0.01, respectively) and fibrous tissue (P=0.01) decreased, but lymphocyte infiltration of the plaque (P=0.03) and cap (P=0.002) and overall plaque inflammation (P=0.03) also decreased such that overall plaque instability was unrelated to age. CONCLUSIONS: Smoking is associated with a lower age at carotid endarterectomy suggesting that it may accelerate the development and/or progression of atherosclerosis. However, the mechanisms of plaque instability seem largely unrelated to smoking. Plaques from younger patients had greater inflammatory cell infiltration, whereas those from older patients had a larger lipid core, but there were no age trends in overall plaque instability suggesting the increased risk of stroke in the elderly with symptomatic carotid stenosis is due to other factors.


Assuntos
Aterosclerose/patologia , Estenose das Carótidas/patologia , Estenose das Carótidas/cirurgia , Fumar , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/cirurgia , Distribuição de Qui-Quadrado , Endarterectomia das Carótidas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
BMJ Open Sport Exerc Med ; 6(1): e000929, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33178448

RESUMO

OBJECTIVES: Exercise programmes studied after stroke often involve specialist supervision. Determine the feasibility and safety for people with stroke (PwS) or transient ischaemic attack (TIA) participating in readily accessible, non-stroke specialised, community-based exercise programmes. METHODS: Participants were recruited into a structured, group-based, 12-week programme of aerobic and resistance exercise delivered two times per week at one of five local leisure centres. Completion rates, successful attainment of intended exercise intensity (Borg Rating of Perceived Exertion (RPE)) and safety outcomes were recorded. Measures of physical activity (International Physical Activity Questionnaire), health-related quality of life (EQ-5D) and blood pressure (BP) were recorded at baseline and day 1 post intervention. RESULTS: 79% of participants completed >75% of the intended sessions, with >90% attainment of intended RPE. Exercise was safe with no serious and very few minor adverse events related to exercise. Exercise led to significant increases in EQ-5D (Best of Health p<0.001), levels of weekly moderate physical activity (p<0.001) and decreases in systolic BP (mean change [95% CI]=-5.4 mmHg [-2.84 to -7.96]; p<0.001). CONCLUSION: Generalised exercise programmes delivered through existing local services, appears feasible, safe and may improve quality of life, physical activity and systolic BP, for PwS and TIA.

19.
Sci Rep ; 10(1): 699, 2020 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959846

RESUMO

Stroke is one of the commonest causes of death with limited treatment options. L-Carnosine has shown great promise as a neuroprotective agent in experimental stroke, but translation to the clinic is impeded by the large doses needed. We developed and evaluated the therapeutic potential of a novel delivery vehicle which encapsulated carnosine in lipoprotein receptor related protein-1 (LRP-1)-targeted functionalized polymersomes in experimental ischemic stroke. We found that following ischemic stroke, polymersomes encapsulating carnosine exhibited remarkable neuroprotective effects with a dose of carnosine 3 orders of magnitude lower than free carnosine. The LRP-1-targeted functionalization was essential for delivery of carnosine to the brain, as non-targeted carnosine polymersomes did not exhibit neuroprotection. Using Cy3 fluorescence in vivo imaging, we showed that unlike non-targeted carnosine polymersomes, LRP-1-targeted carriers accumulated in brain in a time dependent manner. Our findings suggest that these novel carriers have the ability to deliver neuroprotective cargo effectively to the brain.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Carnosina/administração & dosagem , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Peptídeos/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Química Encefálica , Carnosina/química , Carnosina/farmacocinética , Modelos Animais de Doenças , Portadores de Fármacos/química , Composição de Medicamentos , Masculino , Camundongos , Peptídeos/química , Ratos , Fatores de Tempo , Resultado do Tratamento
20.
Front Hum Neurosci ; 14: 568051, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33854421

RESUMO

Given its non-invasive nature, there is increasing interest in the use of transcutaneous vagus nerve stimulation (tVNS) across basic, translational and clinical research. Contemporaneously, tVNS can be achieved by stimulating either the auricular branch or the cervical bundle of the vagus nerve, referred to as transcutaneous auricular vagus nerve stimulation(VNS) and transcutaneous cervical VNS, respectively. In order to advance the field in a systematic manner, studies using these technologies need to adequately report sufficient methodological detail to enable comparison of results between studies, replication of studies, as well as enhancing study participant safety. We systematically reviewed the existing tVNS literature to evaluate current reporting practices. Based on this review, and consensus among participating authors, we propose a set of minimal reporting items to guide future tVNS studies. The suggested items address specific technical aspects of the device and stimulation parameters. We also cover general recommendations including inclusion and exclusion criteria for participants, outcome parameters and the detailed reporting of side effects. Furthermore, we review strategies used to identify the optimal stimulation parameters for a given research setting and summarize ongoing developments in animal research with potential implications for the application of tVNS in humans. Finally, we discuss the potential of tVNS in future research as well as the associated challenges across several disciplines in research and clinical practice.

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