RESUMO
Neuroinflammation is a chronic event in neurodegenerative disorders. In the rat model of Parkinson's disease, including a striatal injection of the neurotoxin 6-hydroxydopamine (6-OHDA), antioxidant treatment affects the inflammatory process. Despite a heavy accumulation of microglia early after the injury, dopamine nerve fibre regeneration occurs. It remains unclear why this heavy accumulation of microglia is found early after the lesion in antioxidant-treated animals, or even more, what is the origin of these microglia. In this study magnetic resonance imaging (MRI) was used to elucidate whether the inflammatory response was generated from the blood or from activated brain microglia. Superparamagnetic iron oxide (SPIO) nanoparticles were injected intravenously prior to a striatal 6-OHDA injection to tag phagocytes in the blood. Rats were fed either with bilberry-enriched or control diet. T2*-weighted MRI scans were performed 1 week after the lesion, and hypointense areas were calculated from T2*-weighted images, to monitor the presence of SPIO particles. The results revealed that feeding the animals with bilberries significantly promoted accumulation of blood-derived immune cells. Gadolinium-enhanced MRI demonstrated no difference in leakage of the blood-brain barrier independent of diets. To conclude, bilberry-enriched diet promotes an influx of periphery-derived immune cells to the brain early after injury.
Assuntos
Encefalite/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Microglia/fisiologia , Monócitos/fisiologia , Neostriado/fisiopatologia , Transtornos Parkinsonianos/fisiopatologia , Extratos Vegetais/administração & dosagem , Vaccinium myrtillus , Animais , Barreira Hematoencefálica/metabolismo , Meios de Contraste , Modelos Animais de Doenças , Encefalite/patologia , Feminino , Nanopartículas de Magnetita/administração & dosagem , Microglia/metabolismo , Monócitos/metabolismo , Neostriado/metabolismo , Neostriado/patologia , Oxidopamina , Transtornos Parkinsonianos/induzido quimicamente , Ratos , Ratos Sprague-DawleyRESUMO
Introduction: Tenecteplase (TNK-tPA) has several benefits over alteplase (tPA) in treatment of acute ischaemic stroke. Randomised controlled trials have shown promising results. In June 2017, the Stroke Unit at Sundsvall County Hospital switched from tPA to TNK-tPA in standard clinical practice. This study examines the effects of that shift. Methods: All thrombolysis treatments performed during the first twenty-four months with TNK-tPA (168) were compared to the last twenty-four months with tPA (191). Data were collected from patient records. Follow-up time was 30 days. Co-primary outcomes were death and symptomatic intracranial haemorrhage (SICH). Secondary outcomes were types of intracerebral bleeding and cause of death. Tertiary outcome was door-to-needle time (DNT). Results: Treatment groups were of comparable age (75.7 ± 0.2 years). tPA-treated patients had an NIHSS (National Institutes of Health Stroke Scale) score of 9.2 versus 7.5 for TNK-tPA. Patients older than 80 had more severe strokes (median NIHSS 9 versus 5). SICH occurred in 6 (3.6 %) patients in the TNK-tPA group and in 2 (1.0 %) treated with tPA, odds ratio (OR) 3.41 (0.70-16.7). Numbers for death were 21 (12.5 %) and 31 (15.2 %), OR 0.77 (0.46-1.29), meaning no statistically significant differences in primary outcomes. There were no significant differences in secondary outcomes. Predominant cause of death was cerebral infarction. DNT with tenecteplase was shorter: mean 44 versus 26, and median 35 versus 19 min. Conclusions: Switching from alteplase to tenecteplase was associated with shorter time to treatment. To draw certain conclusions regarding safety or efficacy would require a larger material.
RESUMO
BACKGROUND: Dizziness and vertigo affect around 15% of adults annually and represent common reasons for contacting health services, accounting for around 3% of all emergency department visits worldwide. Vertigo is also associated with excessive use of diagnostic imaging and emergency care and decreased productivity, primarily because of work absenteeism. Vestibular rehabilitation is an evidence-based treatment for chronic dizziness and supervised group exercise therapy has recently been shown to be effective after vestibular neuritis, a common cause of acute onset vertigo. However, such interventions are not readily available and there is a need for more easily accessible tools. The purpose of this study is to investigate the effects on vestibular symptoms of a 6-week online vestibular rehabilitation tool after acute onset vertigo, with the aim of aiding vestibular rehabilitation by presenting a more accessible tool that can help to reduce recovery time. METHODS: Three hundred twenty individuals diagnosed with acute vestibular syndrome (AVS) will be recruited from multiple hospitals in Sweden and the effects of an online vestibular rehabilitation tool, YrselTräning, on vestibular symptoms after acute onset vertigo will be compared to standard care (written instructions leaflet) in a two-armed, evaluator-blinded, multicenter randomized controlled trial. The primary outcome will be the Vertigo Symptom Scale Short Form (VSS-SF) score at 6 weeks after symptom onset. Secondary outcomes include effects of the intervention on activities of daily living, mood and anxiety, vestibular function recovery, mobility measures, health economic effects, and the reliability of the Swedish VSS-SF translation. DISCUSSION: Participants using the online vestibular rehabilitation tool are expected to recover earlier and to a greater extent from their symptoms as compared to standard care. Since up to 50% of people with AVS without treatment develop persistent symptoms, effective treatment of AVS will likely lead to a higher quality of life and help reduce the societal costs associated with dizziness and vertigo. TRIAL REGISTRATION: Clinicaltrials.gov NCT05056324 . Registered on September 24, 2021.
Assuntos
Tontura , Qualidade de Vida , Atividades Cotidianas , Adulto , Tontura/diagnóstico , Tontura/terapia , Humanos , Internet , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Vertigem/diagnóstico , Vertigem/terapiaRESUMO
Abnormal accumulation of iron is observed in neurodegenerative disorders. In Parkinson's disease, an excess of iron has been demonstrated in different structures of the basal ganglia and is suggested to be involved in the pathogenesis of the disease. Using the 6-hydroxydopamine (6-OHDA) rat model of Parkinson's disease, the edematous effect of 6-OHDA and its relation with striatal iron accumulation was examined utilizing in vivo magnetic resonance imaging (MRI). The results revealed that in comparison with control animals, injection of 6-OHDA into the rat striatum provoked an edematous process, visible in T2-weighted images that was accompanied by an accumulation of iron clearly detectable in T2*-weighted images. Furthermore, Prussian blue staining to detect iron in sectioned brains confirmed the existence of accumulated iron in the areas of T2* hypointensities. The presence of ED1-positive microglia in the lesioned striatum overlapped with this accumulation of iron, indicating areas of toxicity and loss of dopamine nerve fibers. Correlation analyses demonstrated a direct relation between the hyperintensities caused by the edema and the hypointensities caused by the accumulation of iron.