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BACKGROUND: Intraluminal non-occlusive thrombus (ILT) is a rare cause of ischemic stroke. Although in most cases ILT is associated with arterial wall disorders, it has also been documented in patients with thrombophilic conditions. CASE REPORT: We present a case of carotid ILT in a 38-year-old puerperal woman with pregnancy-induced hypercoagulability. Following in vitro fertilization pregnancy, she experienced acute left-sided weakness 9 days after delivery. CT angiography revealed an intraluminal filling defect in the right carotid bulb, suggestive of a thrombus, along with ipsilateral MCA sub-occlusion. Mechanical thrombectomy was performed, achieving complete vessel recanalization without any endovascular intervention on the carotid ILT. Comprehensive evaluation excluded any underlying carotid vessel wall disease (such as atherosclerosis, inflammatory diseases, arterial dissection, focal dysplasia), inherited or acquired thrombophilia, and the sole prothrombotic risk factor identified was the puerperium. Histological thrombus analysis showed fibrin/platelet-rich material with significant macrophage infiltration (consistent with an intermediate/organized thrombus, suggesting potential embolization from a pre-existing carotid ILT). Anti-thrombotic treatment (acetylsalicylic acid 100 mg and enoxaparin 6000 UI) resulted in complete thrombus resolution at follow-up. CONCLUSION: ILT should be considered a potential case of embolic stroke in pregnancy or puerperium. Vessel imaging is essential for diagnosis. Histological thrombus analysis can provide insights into the pathophysiological mechanisms of stroke.
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Acidente Vascular Cerebral , Trombose , Adulto , Feminino , Humanos , Gravidez , Artéria Carótida Interna/patologia , Angiografia por Tomografia Computadorizada , Período Pós-Parto , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Trombose/complicações , Resultado do Tratamento , TrombectomiaRESUMO
BACKGROUND: Endovascular thrombectomy (EVT) is a treatment option in patients with a cerebral venous thrombosis (CVT) who deteriorate despite anticoagulant treatment. Assessment of thrombus composition in CVT may provide insights into the pathophysiology of the disease and suggest new therapeutic strategies. CASE REPORT: A 47-year-old woman (smoking habit and estradiol/progesterone-releasing intra-uterine device) diagnosed with massive CVT underwent EVT (complete recanalization via aspiration catheter and stentriever) due to acute-onset left-sided weakness and dysarthria despite 72 h of full-dose subcutaneous low-molecular heparin. Two main reddish clots (maximum diameter 15 mm) were retrieved. Microscopic assessment showed an erythrocyte-rich thrombus (83.9% of entire thrombus surface) with layers of platelets/fibrin (lines of Zahn: 13.9% fibrin and 38.5% platelet [CD61+]). The immunological profile was dominated by neutrophils (30% MPO+), with neutrophil extracellular traps (NETs) in 1.9% of thrombus surface. T- (CD3+), B-lymphocytes (CD20+), and monocytes/macrophages (CD68+) were rather rare (2.2%, 0.7%, and 2.0% respectively). We found no evidence (0.0%) of hemosiderin and endothelial cells (CD34+). Full clinical recovery occurred prior to discharge. CONCLUSION: This is the first case report of a CVT with histologic assessment of the thrombus retrieved via EVT. Evaluating thrombi in CVT can provide key insights into disease pathophysiology and guide treatment advancements.
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Trombose Intracraniana , Trombose , Trombose Venosa , Feminino , Humanos , Pessoa de Meia-Idade , Células Endoteliais/patologia , Trombectomia , Trombose Intracraniana/complicações , Trombose Intracraniana/diagnóstico por imagem , Trombose Intracraniana/terapia , Trombose Venosa/complicações , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/terapia , FibrinaRESUMO
BACKGROUND: Medium-vessel occlusions (MeVO) are emerging as a new target for endovascular treatment (EVT). Primary MeVO occur de novo, while secondary MeVO arise from large vessel occlusion (LVO) through clot migration or fragmentation - spontaneously, following intravenous thrombolysis or EVT. We aimed to evaluate efficacy and safety of EVT in primary and EVT-induced secondary MeVO. METHODS: Retrospective single-center study on consecutive EVT-treated acute ischemic stroke, from 2019-to-2021. We considered: (1) exclusive-LVO, patients with LVO and - in case of residual distal occlusion - no rescue endovascular procedure; (2) primary MeVO: initial A2, A3, M2 non-dominant, M3, P2, P3 occlusions; (3) EVT-induced secondary MeVO, presenting LVO with subsequent (treated) EVT-induced MeVO. We compared (univariable/multivariable logistic regression) EVT efficacy (eTICI≥2b, 3-month modified Rankin Scale [mRS] 0-2) and safety (EVT-complications [vessel dissection, perforation, persistent-SAH], symptomatic ICH) in all MeVO versus exclusive-LVO, primary MeVO versus exclusive-LVO, EVT-induced secondary MeVO versus exclusive-LVO and EVT-induced secondary MeVO versus primary MeVO. RESULTS: We included 335 patients: 221 (66.0 %) exclusive-LVO and 114 (34.0 %) MeVO (55 [48.2 %] primary, 59 [51.8 %] secondary). Compared to exclusive-LVO, primary MeVO had higher rates of EVT complications (aOR 3.77 [95%CI 1.58-9.00],p=0.003), lower rates of eTICI≥2b (aOR 0.32 [95%CI 0.12-0.88],p=0.027) and mRS 0-2 (aOR 0.28 [95%CI 0.13-0.63],p=0.002). EVT-induced secondary MeVO had no major differences in efficacy and safety outcomes compared to exclusive-LVO, but a better mRS 0-2 (aOR 8.00 [95%CI 2.12-30.17],p=0.002) compared to primary MeVO. CONCLUSIONS: Primary and EVT-induced secondary MeVO showed different safety/efficacy EVT-related profiles. Dedicated randomized data are needed to identify the best acute reperfusion strategy in the two categories.
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Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Estudos Retrospectivos , Trombectomia/efeitos adversos , Isquemia Encefálica/terapia , Resultado do Tratamento , Procedimentos Endovasculares/efeitos adversosRESUMO
BACKGROUND: The benefit of distinguishing between disabling versus nondisabling deficit in mild acute ischemic stroke due to endovascular thrombectomy-targetable vessel occlusion (EVT-tVO; including anterior circulation large and medium-vessel occlusion) is unknown. We compared safety and efficacy of acute reperfusion treatments in disabling versus nondisabling mild EVT-tVO. METHODS: From the Safe Implementation of Treatments in Stroke-International Stroke Thrombolysis Register, we included consecutive acute ischemic stroke patients (2015-2021) treated within 4.5 hours, with full NIHSS items availability and score ≤5, evidence of intracranial internal carotid artery, M1, A1-2, or M2-3 occlusion. After propensity score matching, we compared efficacy (3-month modified Rankin Scale score of 0-1, modified Rankin Scale score of 0-2, and early neurological improvement) and safety (nonhemorrhagic early neurological deterioration, any intracerebral or subarachnoid hemorrhage, symptomatic intracranial hemorrhage, and death at 3-month) outcomes in disabling versus nondisabling patients-adopting an available definition. RESULTS: We included 1459 patients. Propensity score matched analysis of disabling versus nondisabling EVT-tVO (n=336 per group) found no significant differences in efficacy (modified Rankin Scale score 0-1: 67.4% versus 71.5%, P=0.336; modified Rankin Scale score 0-2: 77.1% versus 77.6%, P=0.895; early neurological improvement: 38.3% versus 44.4%, P=0.132) and safety (nonhemorrhagic early neurological deterioration: 8.5% versus 8.0%, P=0.830; any intracerebral hemorrhage or subarachnoid hemorrhage: 12.5% versus 13.3%, P=0.792; symptomatic intracranial hemorrhage: 2.6% versus 3.4%, P=0.598; and 3-month death: 9.8% versus 9.2%, P=0.844) outcomes. CONCLUSIONS: We found similar safety and efficacy outcomes after acute reperfusion treatment in disabling versus nondisabling mild EVT-tVO; our findings suggest to adopt similar acute treatment approaches in the 2 groups. Randomized data are needed to clarify the best reperfusion treatment in mild EVT-tVO.
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AVC Isquêmico , Acidente Vascular Cerebral , Hemorragia Subaracnóidea , Humanos , Acidente Vascular Cerebral/cirurgia , Hemorragias Intracranianas , ReperfusãoRESUMO
INTRODUCTION: Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a prothrombotic syndrome observed after adenoviral vector-based vaccines for severe acute respiratory syndrome coronavirus 2. It is characterized by thrombocytopenia, systemic activation of coagulation, extensive venous thrombosis, and anti-platelet factor 4 antibodies. Arterial thrombosis is less common and mainly affects the aorta, peripheral arteries, heart, and brain. Several cases of ischemic stroke have been reported in VITT, often associated with large vessel occlusion (LVO). Here, we describe a case of ischemic stroke with LVO after Ad26.COV2.S vaccine, then we systematically reviewed the published cases of ischemic stroke and VITT following COVID-19 vaccination. METHODS: We describe a 58-year-old woman who developed a thrombotic thrombocytopenia syndrome with extensive splanchnic vein thrombosis and ischemic stroke due to right middle cerebral artery (MCA) occlusion, 13 days after receiving Ad26.COV2.S vaccination. Then, we performed a systematic review of the literature until December 3, 2021 using PubMed and EMBASE databases. The following keywords were used: ("COVID-19 vaccine") AND ("stroke"), ("COVID-19 vaccine") AND ("thrombotic thrombocytopenia"). We have selected all cases of ischemic stroke in VITT. RESULTS: Our study included 24 patients. The majority of the patients were females (79.2%) and younger than 60 years of age (median age 45.5 years). Almost all patients (96%) received the first dose of an adenoviral vector-based vaccine. Ischemic stroke was the presenting symptom in 18 patients (75%). Splanchnic venous thrombosis was found in 10 patients, and cerebral venous thrombosis in 5 patients (21%). Most patients (87.5%) had an anterior circulation stroke, mainly involving MCA. Seventeen patients (71%) had an intracranial LVO. We found a high prevalence of large intraluminal thrombi (7 patients) and free-floating thrombus (3 patients) in extracranial vessels, such as the carotid artery, in the absence of underlying atherosclerotic disease. Acute reperfusion therapy was performed in 7 of the 17 patients with LVO (41%). One patient with a normal platelet count underwent intravenous thrombolysis with alteplase, while 6 patients underwent mechanical thrombectomy. A malignant infarct occurred in 9 patients and decompressive hemicraniectomy was performed in 7 patients. Five patients died (21%). CONCLUSION: Our study points out that, in addition to cerebral venous thrombosis, adenoviral vector-based vaccines also appear to have a cerebral arterial thrombotic risk, and clinicians should be aware that ischemic stroke with LVO, although rare, could represent a clinical presentation of VITT.
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Vacinas contra COVID-19 , COVID-19 , AVC Isquêmico , Trombocitopenia , Trombose , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ad26COVS1 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/etiologia , VacinasRESUMO
BACKGROUND: The causal relationship between patent foramen ovale (PFO) and migraine with aura (MA) is controversial. We aimed at exploring whether attack clinical features relate to the presence of right-to-left shunt (RLS) in MA patients. METHODS: We retrospectively examined a cohort of consecutive patients diagnosed with MA in our headache center and undergoing transcranial doppler (TCD) for RLS detection. We collected from our clinical electronic dossiers, clinical features of MA attacks (type, frequency, duration of aura phenomenon, trigger factors, onset age), family history for MA, thrombophilia genotypes, and the response to preventive treatments. RLS was stratified for severity according to the results of the TCD examination. RESULTS: We found 111 patients. Binary logistic regression analysis showed that among features of MA attacks, only onset age was associated with the presence of RLS (p < 0.0001). Patients with RLS presented the first MA attack at a younger age (p < 0.0001). The greater RLS severity, the younger was onset age (p < 0.00001) and the presence of atrial septal aneurysms (ASA) was associated with a further decrease in onset age (ρ = -539, p < 0.00001). Family history for MA was associated with the presence of RLS (chi-square p = 0.022). Response to preventive treatments was not influenced by the type of treatment (antiplatelet compared with no antiplatelet drugs), comorbidity with migraine without aura, RLS presence, or by their double interactions (Logistic regression, consistently p > 0.05). CONCLUSION: Our findings support the hypothesis that although PFO does not influence MA attack frequency, it is not merely a bystander in MA physiopathology, as RLS, its severity, and the presence of ASA possibly make a difference in the disease history.
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Circulação Cerebrovascular , Forame Oval Patente/complicações , Enxaqueca com Aura/etiologia , Adolescente , Adulto , Idade de Início , Idoso , Feminino , Forame Oval Patente/diagnóstico por imagem , Forame Oval Patente/fisiopatologia , Aneurisma Cardíaco/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Enxaqueca com Aura/diagnóstico por imagem , Enxaqueca com Aura/fisiopatologia , Enxaqueca com Aura/prevenção & controle , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Ultrassonografia Doppler Transcraniana , Adulto JovemRESUMO
Management of medication overuse headache (MOH) requires abrupt suspension of overused drugs either alone or in association with a detoxification protocol to prevent withdrawal. However, there is no consensus about which suspension strategy is the most effective. Moreover, reliable data about the possible mid-term effect of detoxification are not available. The objective of this study was to evaluate whether a bridge therapy consisting of a 5-day i.v. infusion of methylprednisolone and diazepam determines a significant reduction in headache frequency and drug assumption during the detoxification protocol (day 5) and in the first 3 months in patients with MOH. We conducted a retrospective non-randomized before-and-after study comparing patients with MOH undergoing a bridge therapy protocol (5-day infusion of methylprednisolone, diazepam) with those who refused the treatment and were only recommended to suspend overused painkillers. Both groups started a prophylactic treatment and were followed-up for 3 months. At day 5, 82% of our patients were headache-free; moreover, 48% of the patients did not take any painkiller during the 5-day treatment. Three months after, the intervention group showed a greater reduction of monthly headache days (9.4 vs 3.0) and drugs (19.7 vs 6.5), a greater rate of patients with a ≥ 50% reduction of monthly headaches (p = 0.019) and symptomatic drug consumption (p = 0.000), than the control group. The methylprednisolone and diazepam detoxification protocol reduced headache attacks and drug assumption immediately and in the first 3 months after the intervention, concurring to improve the effect of a new prophylactic therapy.
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Adjuvantes Anestésicos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Diazepam/administração & dosagem , Transtornos da Cefaleia Secundários/tratamento farmacológico , Metilprednisolona/administração & dosagem , Adjuvantes Anestésicos/efeitos adversos , Administração Intravenosa , Análise de Variância , Anti-Inflamatórios/efeitos adversos , Diazepam/efeitos adversos , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Metilprednisolona/efeitos adversos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do TratamentoRESUMO
INTRODUCTION: Endovascular treatment (EVT) improves outcomes for basilar artery occlusion (BAO) with moderate-to-severe symptoms. However, the best treatment for mild symptoms (NIHSS score 0-10 and 0-5) remains unclear. This study compared EVT ± IVT to IVT alone in BAO patients with mild symptoms. PATIENTS AND METHODS: From the SITS-International Stroke Treatment Register, we included BAO patients with available baseline NIHSS score, treated by EVT, IVT, or both within 6 h of symptom onset from 2013 to 2021. Using the Doubly Robust approach (propensity score matching plus multivariable logistic regression), we analyzed efficacy (3-month mRS) and safety (SICH and 3-month death) outcomes for EVT ± IVT versus IVT alone in BAO patients with NIHSS scores 0-10 and 0-5. RESULTS: 1426 patients were included. For NIHSS scores 0-10 (180 matched, 1:1 ratio), outcomes were similar between EVT ± IVT and IVT alone groups. For NIHSS scores 0-5 (89 matched, 1:1 ratio), EVT ± IVT was associated with worse outcomes compared to IVT alone (mRS 0-2, aOR 0.20 [95% CI 0.06-0.61]; p = 0.005; mRS 0-3, aOR 0.27 [95% CI 0.08-0.89]; p = 0.031), but safety outcomes were similar. DISCUSSION: In early-treated BAO patients with mild symptoms, defined as NIHSS 0-10, there were no significant differences in outcomes between EVT ± IVT and IVT alone. However, for very mild symptoms, defined as NIHSS 0-5, IVT alone was associated with better outcomes compared to EVT ± IVT.Conclusion: Randomized trials are crucial to determine the optimal reperfusion therapy for BAO patients with mild symptoms.
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Remdesivir (RDV) was the first Food and Drug Administration (FDA)-approved medication for COVID-19, with discordant data on efficacy in reducing mortality risk and disease progression. In the context of a dynamic and rapidly changing pandemic landscape, the utilization of real-world evidence is of utmost importance. The objective of this study is to evaluate the impact of RDV on patients who have been admitted to two university referral hospitals in Italy due to COVID-19. All patients older than 18 years and hospitalized at two different universities (Bari and Palermo) were enrolled in this study. To minimize the effect of potential confounders, we used propensity score matching with one case (Remdesivir) and one control that never experienced this kind of intervention during hospitalization. Mortality was the primary outcome of our investigation, and it was recorded using death certificates and/or medical records. Severe COVID-19 was defined as admission to the intensive care unit or a qSOFAscore ≥ 2 or CURB65scores ≥ 3. After using propensity score matching, 365 patients taking Remdesivir and 365 controls were included. No significant differences emerged between the two groups in terms of mean age and percentage of females, while patients taking Remdesivir were less frequently active smokers (p < 0.0001). Moreover, the patients taking Remdesivir were less frequently vaccinated against COVID-19. All the other clinical, radiological, and pharmacological parameters were balanced between the two groups. The use of Remdesivir in our cohort was associated with a significantly lower risk of mortality during the follow-up period (HR 0.56; 95% CI 0.37-0.86; p = 0.007). Moreover, RDV was associated with a significantly lower incidence of non-invasive ventilation (OR 0.27; 95% CI 0.20-0.36). Furthermore, in the 365 patients taking Remdesivir, we observed two cases of mild renal failure requiring a reduction in the dosage of Remdesivir and two cases in which the physicians decided to interrupt Remdesivir for bradycardia and for QT elongation. Our study suggests that the use of Remdesivir in hospitalized COVID-19 patients is a safe therapy associated with improved clinical outcomes, including halving of mortality and with a reduction of around 75% of the risk of invasive ventilation. In a constantly changing COVID-19 scenario, ongoing research is necessary to tailor treatment decisions based on the latest scientific evidence and optimize patient outcomes.
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Monofosfato de Adenosina , Monofosfato de Adenosina/análogos & derivados , Alanina , Alanina/análogos & derivados , Antivirais , Tratamento Farmacológico da COVID-19 , COVID-19 , Pontuação de Propensão , Humanos , Alanina/uso terapêutico , Monofosfato de Adenosina/uso terapêutico , Feminino , Masculino , Itália/epidemiologia , Pessoa de Meia-Idade , Idoso , Antivirais/uso terapêutico , COVID-19/mortalidade , COVID-19/epidemiologia , Hospitalização/estatística & dados numéricos , SARS-CoV-2 , Resultado do Tratamento , Idoso de 80 Anos ou mais , Adulto , Estudos RetrospectivosAssuntos
Enxaqueca com Aura/complicações , Enxaqueca com Aura/epidemiologia , Trombofilia/epidemiologia , Trombofilia/etiologia , Adolescente , Adulto , Idoso , Estudos de Coortes , Feminino , Forame Oval Patente/epidemiologia , Humanos , Incidência , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Enxaqueca com Aura/genética , Mutação/genética , Valor Preditivo dos Testes , Inquéritos e Questionários , Trombofilia/genética , Tromboplastina/genética , Ultrassonografia Doppler Transcraniana , Adulto JovemRESUMO
Introduction: The mechanisms subtending the increased stroke risk in migraine with aura (MA) are not fully understood. Our study aims to evaluate if the clinical profile in stroke patients with MA differentiates from those without MA. Methods: We retrieved the prospective registered electronic clinical dossiers of adult patients younger than 60 years with acute ischemic stroke admitted in four hospitals between January 2016 and June 2022. Patients were classified by the history of MA (MA+ and MA-). Results: We identified 851 stroke patients (59 MA+, 6.9%). Compared to MA-, MA+ patients were characterized by younger age (44.0 ± 10.6 vs 50.1 ± 8.2 years), female sex (59.3% vs 29.0%), and affected by cryptogenic (OR 2.594 95% CI 1.483-4.537), and cerebellar stroke (OR 3.218 95% CI 1.657-6.250; p ≤ 0.001 for all comparisons). After adjusting for age and sex, MA+ patients presented less frequently hypertension (OR 0.349 95% CI 0.167-0.470; p=0.005) and dyslipidemia (OR 0.523 95% CI 0.280-0.974; p = 0.041). After adjusting also for risk factors, the MA+ group had less frequently symptomatic large vessel stenosis (OR 0.126 95% CI 0.017-0,924; p = 0.042) and clinical atherosclerosis (OR 0.103 95% CI 0.014-0.761; p = 0.026), while intima-media thickness did not differ (p = 0.395). Discussion: Cryptogenic and cerebellar stroke and fewer vascular risk factors and clinical atherosclerosis seem to characterize stroke patients with MA.
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OBJECTIVE: To identify the clinical profile and aura characteristics of patients with Migraine with Aura (MwA) having acute cerebral ischemia, we compared stroke phenotype and risk factors in stroke patients with (S+MwA+) or without (S+MwA-) MwA and aura features in MwA patients with (S+MwA+) or without (S-MwA+) stroke. METHODS: In this retrospective multicenter case-control study, we reviewed stroke phenotypes and vascular risk factors in S+MwA+ and S+MwA- patients younger than 60 years and risk factors and aura type, duration, onset age, and the frequency in the previous year in S+MwA+ patients and S-MwA+ subjects matched for age and disease history, investigated for patent foramen ovale (PFO). RESULTS: 539 stroke (7.7% S+MwA+) and 94 S-MwA + patients were enrolled. S+MwA+ patients were younger (p =.0.004) and more frequently presented PFO [OR 4.89 (95% CI 2.12-11.27)], septal interatrial aneurism [OR 2.69 (95% CI 1.15-6.27)] and cryptogenic ischemic stroke (CIS) [OR 6.80 (95% CI 3.26-14.18)] than S+MwA- subjects. Significant atherosclerosis was not detected in S+MwA+ patients. Compared to S-MwA+, S+MwA+ patients were characterized by visual [OR 3.82 (95% CI 1.36-10.66)] and shorter-lasting (20.0 min IQr 13.1 vs 30.0 min IQr 25.0; p < 0.001) aura, and PFO [OR 1.26 (95% CI 1.03-1.54)]. Regression analysis evidenced that only shorter aura duration associated with stroke (p = 0.001). High-risk PFO was equally represented in S+MwA-, S+MwA+, S-MwA+ groups. CONCLUSIONS: Shorter visual aura and CIS characterize MwA patients with stroke. Although more prevalent, PFO can not be considered the main responsible for the increased stroke risk in MwA patients but as a part of a complex multifactorial condition.
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Epilepsia , Forame Oval Patente , Enxaqueca com Aura , Estudos de Casos e Controles , Forame Oval Patente/complicações , Forame Oval Patente/diagnóstico por imagem , Forame Oval Patente/epidemiologia , Humanos , Pessoa de Meia-Idade , Enxaqueca com Aura/epidemiologia , Estudos RetrospectivosRESUMO
Zebrafish spontaneously use distance and directional relationships among three-dimensional extended surfaces to reorient within a rectangular arena. However, they fail to take advantage of either an array of freestanding corners or an array of unequal-length surfaces to search for a no-longer-present goal under a spontaneous cued memory procedure, being unable to use the information supplied by corners and length without some kind of rewarded training. The present study aimed to tease apart the geometric components characterizing a rectangular enclosure under a procedure recruiting the reference memory, thus training zebrafish in fragmented layouts that provided differences in surface distance, corners, and length. Results showed that fish, besides the distance, easily learned to use both corners and length if subjected to a rewarded exit task over time, suggesting that they can represent all the geometrically informative parts of a rectangular arena when consistently exposed to them. Altogether, these findings highlight crucially important issues apropos the employment of different behavioral protocols (spontaneous choice versus training over time) to assess spatial abilities of zebrafish, further paving the way to deepen the role of visual and nonvisual encodings of isolated geometric components in relation to macrostructural boundaries.
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Investigating perceptual and cognitive abilities of zoo animals might help to improve their husbandry and enrich their daily life with new stimuli. Developing new environmental enrichment programs and devices is hence necessary to promote species-specific behaviors that need to be maintained in controlled environments. As far as we are aware, no study has ever tested the potential benefits of motion illusions as visual enrichment for zoo animals. Starting from a recent study showing that domestic cats are spontaneously attracted by a well-known motion illusion, the Rotating Snake (RS) illusion, we studied whether this illusion could be used as a visual enrichment for big cats. We observed the spontaneous behavior of three lionesses when three different visual stimuli were placed in their environment: the RS illusion and two control stimuli. The study involved two different periods: the baseline and the RS period, in which the visual stimuli were provided to the lionesses. To assess whether the lionesses were specifically attracted by the RS illusion, we collected data on the number of interactions with the stimuli, as well as on the total time spent interacting with them. To investigate the effect of the illusion on the animals' welfare, individual and social behaviors were studied, and compared between the two periods. The results showed that two lionesses out of three interacted more with the RS stimulus than with the two control stimuli. The fact that the lionesses seemed to be more inclined to interact with the RS stimulus indirectly suggests the intriguing possibility that they were attracted by the illusory motion. Moreover, behavioral changes between the two periods were reported for one of the lionesses, highlighting a reduction in self-directed behaviors and an increase in attentive behaviors, and suggesting positive welfare implications. Thus, behavioral observations made before and during the presentation of the stimuli showed that our visual enrichment actually provided positive effects in lionesses. These results call for the development of future studies on the use of visual illusions in the enrichment programs of zoo animals.
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Patent Foramen Ovale and impaired cerebral hemodynamics were proposed among the pathophysiological mechanisms explaining the increased risk for stroke in patients with Migraine with Aura (MA). Our study aimed at comparing the vasomotor reactivity (VMR) of the anterior and the posterior cerebral circulation in patients with Migraine with Aura, in patients with acute vascular ischemic accidents, and in controls. We hypothesized that VMR in MA patients is preserved in the anterior circulation and reduced in the posterior circulation. We prospectively assessed with Transcranial Doppler the vasomotor reactivity to breath holding of the Middle and Posterior Cerebral Arteries (MCA, PCA) in MA patients, in acute vascular patients and healthy controls. We also evaluated the possible effect of clinical characteristics of MA (attack frequency, aura length or type, disease history), vascular factors and the presence of right-to-left shunt on VMR. Diverging from our hypothesis, MA patients displayed a higher breath-holding index (BHI) than controls in the MCA (1.84±0.47%/s vs 1.53±0.47%/s, p = .001) as well as in the PCA (1.87±0.65%/s vs 1.47±0.44%/s, p < .001). In MA patients, MCA BHI was higher in those with large right-to-left shunts (2.09±0.42 vs 1.79±0.47, p = .046) and lower in those taking estrogens (1.30±0.30%/s vs 1.9±0.45%/s, p = .009). We did not observe an effect of MA characteristics on BHI. The increased BHI in MA patients with large right-to-left shunts could be explained by the vasoactive effect in the cerebral circulation of substances bypassing the deactivating pulmonary filters or by a constitutional trait of the vascular system associating persistent right-to-left shunts and hyper-reactive hemodynamics. Our results discourage the hypothesis that altered hemodynamics contribute to increasing the stroke risk in all MA patients. However, estrogens can lower VMR, curtailing the hemodynamic resources of MA patients.