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Vascular endothelial function is challenged during cerebral ischemia and reperfusion. The endothelial responses are involved in inflammatory leukocyte attraction, adhesion and infiltration, blood–brain barrier leakage, and angiogenesis. This study investigated gene expression changes in brain endothelial cells after acute ischemic stroke using transcriptomics and translatomics. We isolated brain endothelial mRNA by: (i) translating ribosome affinity purification, enabling immunoprecipitation of brain endothelial ribosome-attached mRNA for translatome sequencing and (ii) isolating CD31+ endothelial cells by fluorescence-activating cell sorting for classical transcriptomic analysis. Both techniques revealed similar pathways regulated by ischemia but they showed specific differences in some transcripts derived from non-endothelial cells. We defined a gene set characterizing the endothelial response to acute stroke (24h) by selecting the differentially expressed genes common to both techniques, thus corresponding with the translatome and minimizing non-endothelial mRNA contamination. Enriched pathways were related to inflammation and immunoregulation, angiogenesis, extracellular matrix, oxidative stress, and lipid trafficking and storage. We validated, by flow cytometry and immunofluorescence, the protein expression of several genes encoding cell surface proteins. The inflammatory response was associated with the endothelial upregulation of genes related to lipid storage functions and we identified lipid droplet biogenesis in the endothelial cells after ischemia. The study reports a robust translatomic signature of brain endothelial cells after acute stroke and identifies enrichment in novel pathways involved in membrane signaling and lipid storage. Altogether these results highlight the endothelial contribution to the inflammatory response, and identify novel molecules that could be targets to improve vascular function after ischemic stroke. [ABSTRACT FROM AUTHOR]

Objective The rate of progression of the ischemic lesion is variable in patients with stroke. We tested the hypothesis that the tissue saving effect of mechanical thrombectomy (MT) is greater in fast progressors. Methods A single-center cohort of consecutive patients (n=242) with occlusions of the terminal internal carotid or M1 segment of the middle cerebral artery treated with MT (n=195) or best medical treatment (n=47), known time from onset, and full imaging (baseline CT perfusion and follow-up MRI) available was studied. The estimated infarct progression rate (eIPR) was calculated at baseline and patients were categorized as fast/slow progressors according to the median eIPR of 4.8 mL/hour. The primary outcome measure was the interaction between eIPR category and MT on infarct growth. The secondary outcomes assessed the effect of MT on final infarct volume and functional status in relation to the eIPR category. The safety outcomes were mortality and symptomatic intracranial hemorrhage. results The eIPR category had a modifying effect (Pi=0.017) of MT on infarct growth that was significantly reduced with MT only in fast progressors (median (IQR) 3.8 mL (-11-55) vs 41 mL (11-107) with medical treatment; p=0.009, adjusted p=0.045). There was also a significant interaction on final infarct volume (Pi=0.005), with a greater reduction after MT in fast progressors. The functional status improved with MT both in fast and slow progressors, with no significant modifying effect of eIPR category (Pi=0.201). There were also no significant interactions on safety outcomes. Conclusion MT in stroke patients with large vessel occlusion limits infarct growth more significantly in fast progressors. [ABSTRACT FROM AUTHOR]

Background and purpose Our aim was to revalidate the race scale, a prehospital tool that aims to identify patients with large vessel occlusion (lVO), after its region-wide implementation in catalonia, and to analyze geographical differences in access to endovascular treatment (EVT). Methods We used data from the prospective cicaT registry (stroke code catalan registry) that includes all stroke code activations. The race score evaluated by emergency medical services, time metrics, final diagnosis, presence of LVO, and type of revascularization treatment were registered. sensitivity, specificity, and area under the curve (AUC) for the race cut-off value ≥5 for identification of both LVO and eligibility for EVT were calculated. We compared the rate of EVT and time to EVT of patients transferred from referral centers compared with those directly presenting to comprehensive stroke centers (CSC). results The race scale was evaluated in the field in 1822 patients, showing a strong correlation with the subsequent in-hospital evaluation of the national institute of health stroke scale evaluated at hospital (r=0.74, P<0.001). a race score ≥5 detected lVO with a sensitivity 0.84 and specificity 0.60 (AUC 0.77). Patients with race ≥5 harbored a LVO and received EVT more frequently than race <5 patients (LVO 35% vs 6%; EVT 20% vs 6%; all P<0.001). Direct admission at a CSC was independently associated with higher odds of receiving EVT compared with admission at a referral center (Or 2.40; 95% CI 1.66 to 3.46), and symtoms onset to groin puncture was 133 min shorter. Conclusions This large validation study confirms race accuracy to identify stroke patients eligible for EVT, and provides evidence of geographical imbalances in the access to EVT to the detriment of patients located in remote areas. [ABSTRACT FROM AUTHOR]

Intravenous thrombolysis is contraindicated in acute ischemic stroke secondary to infective endocarditis. We report our initial experience in 6 cases of proximal vessel occlusion treated with mechanical thrombectomy, which was safe (no bleeding) and effective (significant early neurological improvement) and might be useful in this clinical setting. [ABSTRACT FROM AUTHOR]

Background: Numerous neuroprotective drugs have failed to show benefit in the treatment of acute ischemic stroke, making the search for new treatments imperative. Uric acid is an endogenous antioxidant making it a drug candidate to improve stroke outcomes. Aim: To report the effects of uric acid therapy in stroke patients receiving intravenous thrombolysis and mechanical thrombectomy. Methods: Forty-five patients with proximal vessel occlusions enrolled in the URICO-ICTUS trial received intravenous recombinant tissue plasminogen activator within 4.5 h after stroke onset and randomized to intravenous 1000 mg uric acid or placebo (NCT00860366). These patients also received mechanical thrombectomy because a brain computed tomogaphy angiography confirmed the lack of proximal recanalization at the end of systemic thrombolysis. The primary outcome was good functional outcome at 90 days (modified Rankin Score 0-2). Safety outcomes included mortality, symptomatic intracerebral bleeding, and gout attacks. Results: The rate of successful revascularization was >80% in the uric acid and the placebo groups but good functional outcome was observed in 16 out of 24 (67%) patients treated with uric acid and 10 out of 21 (48%) treated with placebo (adjusted Odds Ratio, 6.12 (95% CI 1.08-34.56)). Mortality was observed in two out of 24 (8.3%) patients treated with uric acid and one out of 21 (4.8%) treated with placebo (adjusted Odds Ratio, 3.74 (95% CI 0.06-226.29)). Symptomatic cerebral bleeding and gout attacks were similar in both groups. Conclusions: Uric acid therapy was safe and improved stroke outcomes in stroke patients receiving intravenous thrombolysis followed by thrombectomy. Validation of this simple strategy in a larger trial is urgent. [ABSTRACT FROM AUTHOR]

The aim of the ICARO-3 study was to evaluate whether intra-arterial treatment, compared to intravenous thrombolysis, increases the rate of favourable functional outcome at 3 months in acute ischemic stroke and extracranial ICA occlusion. ICARO-3 was a non-randomized therapeutic trial that performed a non-blind assessment of outcomes using retrospective data collected prospectively from 37 centres in 7 countries. Patients treated with endovascular treatment within 6 h from stroke onset (cases) were matched with patients treated with intravenous thrombolysis within 4.5 h from symptom onset (controls). Patients receiving either intravenous or endovascular therapy were included among the cases. The efficacy outcome was disability at 90 days assessed by the modified Rankin Scale (mRS), dichotomized as favourable (score of 0-2) or unfavourable (score of 3-6). Safety outcomes were death and any intracranial bleeding. Included in the analysis were 324 cases and 324 controls: 105 cases (32.4 %) had a favourable outcome as compared with 89 controls (27.4 %) [adjusted odds ratio (OR) 1.25, 95 % confidence interval (CI) 0.88-1.79, p = 0.1]. In the adjusted analysis, treatment with intra-arterial procedures was significantly associated with a reduction of mortality (OR 0.61, 95 % CI 0.40-0.93, p = 0.022). The rates of patients with severe disability or death (mRS 5-6) were similar in cases and controls (30.5 versus 32.4 %, p = 0.67). For the ordinal analysis, adjusted for age, sex, NIHSS, presence of diabetes mellitus and atrial fibrillation, the common odds ratio was 1.15 (95 % IC 0.86-1.54), p = 0.33. There were more cases of intracranial bleeding (37.0 versus 17.3 %, p = 0.0001) in the intra-arterial procedure group than in the intravenous group. After the exclusion of the 135 cases treated with the combination of I.V. thrombolysis and I.A. procedures, 67/189 of those treated with I.A. procedures (35.3 %) had a favourable outcome, compared to 89/324 of those treated with I.V. thrombolysis (27.4 %) (adjusted OR 1.75, 95 % CI 1.00-3.03, p = 0.05). Endovascular treatment of patients with acute ICA occlusion did not result in a better functional outcome than treatment with intravenous thrombolysis, but was associated with a higher rate of intracranial bleeding. Overall mortality was significantly reduced in patients treated with endovascular treatment but the rates of patients with severe disability or death were similar. When excluding all patients treated with the combination of I.V. thrombolysis and I.A. procedures, a potential benefit of I.A. treatment alone compared to I.V. thrombolysis was observed. [ABSTRACT FROM AUTHOR]

In this update we review studies on a wide range of topics, from diagnostic aspects of acute stroke to the clinical implications of the complex interaction between the brain and the immune system. Recent randomized trials and observational studies have reinforced the effectiveness of intravenous thrombolysis with t-PA in patients that qualify for this treatment, including patients presenting with mild symptoms or on subtherapeutic oral anticoagulation. Despite all the negative studies on the endovascular treatment of acute stroke, the utility of newer mechanical thrombectomy devices in patients with stroke and large vessel occlusion is being assessed in ongoing clinical trials. In addition to the various revascularization therapies that have a limited time window, treatments aimed at protecting the neurovascular unit may be used in more patients if their efficacy is confirmed in humans, and experimental studies suggest that the modulation of specific aspects of the immune system may increase the likelihood of successful recovery after cerebral ischemia. [ABSTRACT FROM AUTHOR]

Oxidative stress as well as expression and activity of matrix metalloproteinase 9 (MMP-9) are rapidly enhanced after cerebral ischemia. The magnitude of these effects is related to stroke outcome. In human stroke, the extent of oxidative stress correlates well with increased MMP-9 expression. The aim of this study was to evaluate whether treatment with the antioxidant molecule uric acid (UA) decreased the levels of MMP-9 in stroke patients treated with rtPA. The patients were part of a pilot, double-blind, randomized, vehiclecontrolled study of patients with acute stroke treated with rtPA (< 3 h) and randomized to receive an intravenous infusion of UA (n = 16) or vehicle (n = 8). Total matrix metalloproteinase (tMMP)-9 and active (aMMP-9) levels were measured in serum at baseline (< 3 h), at the end of study treatment infusion (< 5.5 h), and at 48 hours. Total MMP-9 and aMMP-9 increased very early after stroke onset in patients allocated vehicle after rtPA therapy. Lower increments of aMMP-9 were associated with better outcome at 3 months. UA treatment was associated with reduced levels of aMMP-9 at T1 (p < 0.02) in multivariate models adjusted for age, NIHSS score, and baseline aMMP-9 levels. The decline of aMMP-9 attained after UA administration supports further clinical assessment of UA therapy in patients with acute stroke. [ABSTRACT FROM AUTHOR]

The article discusses the experience of treating mechanical thrombectomy (MT) in infectious endocarditis (IE). It examines the complications in the use of revascularization and neurological recovery, main risk factors like central nervous system bleeding during revascularization and analyzing cases of endocarditis cohort.

Acute stroke induces a local inflammatory reaction causing leukocyte infiltration. Circulating monocytes are recruited to the ischemic brain and become tissue macrophages morphologically indistinguishable from reactive microglia. However, monocytes are a heterogeneous population of cells with different functions. Herein, we investigated the infiltration and fate of the monocyte subsets in a mouse model of focal brain ischemia by permanent occlusion of the distal portion of the middle cerebral artery. We separated two main subtypes of CD11b hi monocytes according to their expression of the surface markers Ly6C and CD43. Using adoptive transfer of reporter monocytes and monocyte depletion, we identified the pro-inflammatory Ly6C hi CD43 lo CCR2 + subset as the predominant monocytes recruited to the ischemic tissue. Monocytes were seen in the leptomeninges from where they entered the cortex along the penetrating arterioles. Four days post-ischemia, they had invaded the infarcted core, where they were often located adjacent to blood vessels. At this time, Iba-1 − and Iba-1 + cells in the ischemic tissue incorporated BrdU, but BrdU incorporation was rare in the reporter monocytes. The monocyte phenotype progressively changed by down-regulating Ly6C, up-regulating F4/80, expressing low or intermediate levels of Iba-1, and developing macrophage morphology. Moreover, monocytes progressively acquired the expression of typical markers of alternatively activated macrophages, like arginase-1 and YM-1. Collectively, the results show that stroke mobilized immature pro-inflammatory Ly6C hi CD43 lo monocytes that acutely infiltrated the ischemic tissue reaching the core of the lesion. Monocytes differentiated to macrophages with features of alternative activation suggesting possible roles in tissue repair during the sub-acute phase of stroke. [ABSTRACT FROM AUTHOR]

Recent clinical and experimental studies have highlighted a complex role for the immune system in the pathophysiological changes that occur after acute stroke. Sensors of the innate immune system such as Toll-like receptors, or effectors such as the lectin pathway of complement activation and innate immune cells, are activated by brain ischaemia and tissue damage, leading to amplification of the inflammatory cascade. Activation of the adaptive arm of the immune system, mediated by lymphocyte populations including T and B cells, regulatory T cells, and y6T cells, in response to stroke can lead to deleterious antigen-specific autoreactive responses but can also have cytoprotective effects. Increased incidence of infections is observed after acute stroke, and might result from activation of long-distance feedback loops between the CNS and peripheral immune organs, which are thought to play a part in stroke-induced immunodepression. Ongoing clinical trials are investigating whether the preventive use of antibiotics improves functional outcome after stroke. This Review discusses the multifaceted role of the immune system in the pathophysiology of acute stroke. [ABSTRACT FROM AUTHOR]