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Using ferric chloride (FeCl3) to induce experimental superior sagittal sinus (SSS) thrombosis might interfere with magnetic resonance imaging (MRI)-assisted visualization and evaluation of the thrombus, the brain parenchyma, and the quality of the occlusion. The aim of this study was to investigate whether aluminum chloride (AlCl3)-induced thrombosis of the SSS has comparable properties to those of FeCl3 without causing artifacts in MRI. SSS thrombosis was induced in 14 male Wistar rats by exposure of the SSS and subsequent topical application of a filter paper strip soaked in AlCl3 (n = 7) or FeCl3 (n = 7) over a period of 15 min. The animals with AlCl3-induced SSS thrombosis showed a constant and complete occlusion with in histological analysis large thrombi. Blood flow measurements indicated a significant reduction on the first and seventh postoperative day compared to preoperative measurements. MRI enabled visualization and subsequent evaluation of the thrombus and the surrounding parenchyma. In comparison, FeCl3-induced SSS thrombosis could not be evaluated by MRI due to artifacts caused by the paramagnetic properties and increased susceptibility of FeCl3. The occluded sinus and the surrounding area appeared hypointense. The quality of SSS occlusion by AlCl3 was comparable to that of FeCl3. AlCl3 therefore represents a significant alternative substance in experimental SSS thrombosis ideally suited for studies using MRI. [ABSTRACT FROM AUTHOR]

Background: Lipid droplets (LD), lipid-storing organelles containing neutral lipids like glycerolipids and cholesterol, are increasingly accepted as hallmarks of inflammation. The nuclear paraspeckle assembly transcript 1 (NEAT1), a long non-coding RNA with over 200 nucleotides, exerts an indispensable impact on regulating both LD agglomeration and autophagy in multiple neurological disorders. However, knowledge as to how NEAT1 modulates the formation of LD and associated signaling pathways is limited. Methods: In this study, primary microglia were isolated from newborn mice and exposed to oxygen-glucose-deprivation/reoxygenation (OGD/R). To further explore NEAT1-dependent mechanisms, an antisense oligonucleotide (ASO) was adopted to silence NEAT1 under in vitro conditions. Studying NEAT1-dependent interactions with regard to autophagy and LD agglomeration under hypoxic conditions, the inhibitor and activator of autophagy 3-methyladenine (3-MA) and rapamycin (RAPA) were used, respectively. In a preclinical stroke model, mice received intraventricular injections of ASO NEAT1 or control vectors in order to yield NEAT1 knockdown. Analysis of readout parameters included qRT-PCR, immunofluorescence, western blot assays, and behavioral tests. Results: Microglia exposed to OGD/R displayed a temporal pattern of NEAT1 expression, peaking at four hours of hypoxia followed by six hours of reoxygenation. After effectively silencing NEAT1, LD formation and autophagy-related proteins were significantly repressed in hypoxic microglia. Stimulating autophagy in ASO NEAT1 microglia under OGD/R conditions by means of RAPA reversed the downregulation of LD agglomeration and perilipin 2 (PLIN2) expression. On the contrary, application of 3-MA promoted repression of both LD agglomeration and expression of the LD-associated protein PLIN2. Under in vivo conditions, NEAT1 was significantly increased in mice at 24 h post-stroke. Knockdown of NEAT1 significantly alleviated LD agglomeration and inhibited autophagy, resulting in improved cerebral perfusion, reduced brain injury and increased neurological recovery. Conclusion: NEAT1 is a key player of LD agglomeration and autophagy stimulation, and NEAT1 knockdown provides a promising therapeutic value against stroke. [ABSTRACT FROM AUTHOR]

Hypoxia triggers reactive microglial inflammation and lipid droplet (LD) accumulation under stroke conditions, although the mutual interactions between these two processes are insufficiently understood. Hence, the involvement of transforming growth factor (TGF)-β1 in inflammation and LD accumulation in cultured microglia exposed to hypoxia were analyzed herein. Primary microglia were exposed to oxygen-glucose deprivation (OGD) injury and lipopolysaccharide (LPS) stimulation. For analyzing the role of TGF-β1 patterns under such conditions, a TGF-β1 siRNA and an exogenous recombinant TGF-β1 protein were employed. Further studies applied Triacsin C, an inhibitor of LD formation, in order to directly assess the impact of LD formation on the modulation of inflammation. To assess mutual microglia-to-neuron interactions, a co-culture model of these cells was established. Upon OGD exposure, microglial TGF-β1 levels were significantly increased, whereas LPS stimulation yielded decreased levels. Elevating TGF-β1 expression proved highly effective in suppressing inflammation and reducing LD accumulation in microglia exposed to LPS. Conversely, inhibition of TGF-β1 led to the promotion of microglial cell inflammation and an increase in LD accumulation in microglia exposed to OGD. Employing the LD formation inhibitor Triacsin C, in turn, polarized microglia towards an anti-inflammatory phenotype. Such modulation of both microglial TGF-β1 and LD levels significantly affected the resistance of co-cultured neurons. This study provides novel insights by demonstrating that TGF-β1 plays a protective role against microglia-mediated neuroinflammation through the suppression of LD accumulation. These findings offer a fresh perspective on stroke treatment, suggesting the potential of targeting this pathway for therapeutic interventions. [ABSTRACT FROM AUTHOR]

Background: Spontaneous intracerebral hemorrhage (ICH) is a frequent cerebrovascular disorder and still associated with high mortality and poor clinical outcomes. The purpose of this review was to update a 15-year-old former meta-analysis on randomized clinical trials (RCTs) addressing the question of whether ICH patients treated with dexamethasone have better outcomes than controls. Methods: The electronic databases PubMed, SCOPUS, and Cochrane as well as web platforms on current clinical trials were searched for the years 1970–2020 without constriction on language. Data were extracted and outcomes were pooled for conventional and cumulative meta-analysis using a commercial software program (www.Meta-Analysis.com). Results: Finally, 7 RCTs were identified and analyzed including 248 participants in the dexamethasone groups and 242 in the control groups. Five studies showed a high risk of bias. The overall relative risk (RR) for death was 1.32 (95% confidence interval [CI] 0.99–1.76; p = 0.06) and did not differ significantly between the 2 groups. After exclusion of studies with high risk of bias, the RR for death was 1.37 (95% CI 0.54–3.42; p = 0.51). The RR for poor outcome did not differ significantly between the 2 groups analyzed for all included studies (RR = 0.69; 95% CI 0.47–1; p = 0.05) and after exclusion of studies with high risk of bias (RR = 0.7; 95% CI 0.45–1.08; p = 0.11). The RR for complications did not differ significantly including all studies (RR = 1.29; 95% CI 0.77–2.17; p = 0.34) and after exclusion of studies with high risk of bias (RR = 1.27; 95% CI 0.18–8.89; p = 0.81). The cumulative statistics delivered no other results; however, it pointed out fewer complications over time in the dexamethasone group. Conclusion: Clear evidence of a beneficial or negative effect of dexamethasone is still lacking. Modern RCTs or observational studies with propensity design are necessary to evaluate the efficacy and safety of treatment with dexamethasone in patients with ICH. [ABSTRACT FROM AUTHOR]

Purpose: Recent studies postulate a high prognostic value of the Alberta Stroke Programme Early CT Score (ASPECTS) applied on non-contrast whole-brain flat-detector CT (FDCT) after successful endovascular treatment (EVT). The aim of this study was the evaluation of long-term patient outcome after endovascular treatment using postinterventional FDCT. Methods: Using a local database (Stroke Research Consortium in Northern Bavaria, STAMINA), 517 patients with successful endovascular treatment (modified Thrombolysis in Cerebral Infarction (mTICI) ≥ 2B) due to acute ischaemic stroke (AIS) and large vessel occlusion (LVO) of the anterior circulation were recruited retrospectively. In all cases, non-contrast FDCT after EVT was analysed with special focus at ASPECTS. These results were correlated with the functional outcome in long-term (modified Rankin Scale (mRS) shift from pre-stroke to 90 days after discharge). Results: A significant difference in FDCT-ASPECTS compared to the subgroup of favourable vs. unfavourable outcome (Δ mRS) (median ASPECTS 10 (10–9) vs. median ASPECTS 9 (10–7); p = 0,001) could be demonstrated. Multivariable regression analysis revealed FDCT-ASPECTS (OR 0.234, 95% CI − 0.102–0.008, p = 0.022) along with the NHISS at admission (OR 0.169, 95% CI 0.003–0.018, p = 0.008) as independent factors for a favourable outcome. Cut-off point for a favourable outcome (Δ mRS) was identified at an ASPECTS ≥ 8 (sensitivity 90.6%, specificity 35%). Conclusion: For patients with LVO and successful EVT, FDCT-ASPECTS was found to be highly reliable in predicting long-term outcome. [ABSTRACT FROM AUTHOR]

Background Intracerebral hemorrhage accounts for up to 15% of all strokes and is frequently associated with poor functional outcome and high mortality. So far, there is no clear evidence for a specific therapy, apart from general stroke unit or neurointensive care and management of secondary complications. Promising experimental and pilot clinical data support the use of therapeutic hypothermia after intracerebral hemorrhage. Aims The study aims to determine if therapeutic hypothermia improves survival rates and reduces cerebral lesion volume after large intracerebral hemorrhage compared with conventional treatment. Material and methods The Cooling in IntraCerebral Hemorrhage trial is a prospective, multicenter, interventional, randomized, parallel, two-arm (1 : 1) phase II trial with blinded end-point adjudication. Enrolment: 50 patients (age: 18 to 65 years) with large (25 to 64 ml on cranial computertomography), primary intracerebral hemorrhage of the basal ganglia or thalamus within 6 to 18 h after symptom onset are randomly allocated to therapeutic hypothermia for eight-days or conventional temperature management. In the therapeutic hypothermia group, a target temperature of 35·0° C is achieved by endovascular catheters and followed by slow controlled rewarming. Data analysis is based on the intent-to-treat population. The primary outcome measure of the study is the development in total lesion volume on cranial computertomography (intracerebral hemorrhage plus perihemorrhagic edema on day 8 ± 0·5 and day 11 ± 0·5 after intracerebral hemorrhage) and the mortality after 30 days. Secondary end-points are the in-hospital mortality, mortality, and functional outcome (modified Rankin Scale and Barthel-Index) after 90 and 180 days. Safety measures include any adverse events associated with therapeutic hypothermia. Discussion In the face of a lack of evidence-based therapies for patients with large intracerebral hemorrhage, new promising approaches are desperately needed, but need evaluation in randomized controlled trials. Conclusion The results of Cooling in IntraCerebral Hemorrhage trial are believed to directly influence future therapy of large intracerebral hemorrhage. [ABSTRACT FROM AUTHOR]

Background: Inflammatory response is the hallmark of secondary brain injury in stroke patients. Neutrophil-to-lymphocyte ratio (NLR) emerged as a marker for functional outcome in several diseases.Objectives: To investigate the association between NLR on admission and during hospital stay and functional outcome in acute ischemic stroke (AIS).Methods: This observational study included all consecutive AIS patients admitted at a German stroke center covering 2011-2013. Patient characteristics and clinical data were retrieved from institutional databases. Multivariate analysis was conducted to investigate parameters associated with functional outcome. Receiver operating characteristic (ROC) analysis was performed to identify the best cutoff for NLR to discriminate between favorable and unfavorable functional outcome. To account for imbalances in baseline characteristics, propensity score matching was carried out to assess the influence of NLR on functional outcome.Results: A total of 807 patients with AIS were included for analysis. Patients with worse functional outcome at 3 months were older and had worse clinical status on admission, higher rates of infectious complications, and an increased NLR. ROC analysis identified a NLR of 3.3 as best cutoff value to discriminate between favorable and unfavorable functional outcomes (area under the curve 0.693, p < 0.001, Youden's index = 0.318; p < 0.001; sensitivity 68.5%, specificity 63.9%). Propensity-matched analysis still demonstrated a higher rate of unfavorable functional outcome at 3 months in patients with NLR ≥ 3.3 [modified Rankin scale 3-6 at 3 months: NLR ≥ 3.3 51.5% vs. NLR < 3.3 36.4%; p = 0.002].Conclusions: In AIS patients we identified NLR as an important predictor for unfavorable functional outcome. [ABSTRACT FROM AUTHOR]

Background and purpose: In patients with acute ischemic stroke and large vessel occlusion, the prognosis has improved tremendously since the implementation of endovascular thrombectomy (EVT). The effect of EVT on the incidence of malignant middle cerebral artery infarctions (MMI) has not been studied before.Methods: ESTIMATE, a multicenter retrospective study, evaluates data of ischemic stroke patients with occlusion in the anterior circulation in the years of 2007-2015 comparing three treatment options (no therapy; IV-TPA; IV-TPA plus EVT or EVT only). Primary endpoint of the study was the incidence of MMI on follow-up imaging and mortality rates. Secondary endpoints were functional outcome, further clinical and imaging data. Logistic and Cox-regression models with a propensity score weighting approach were applied to evaluate differences between treatment groups.Results: In 2161 patients over 9 years, EVT reduced the MMI rates significantly: patients without acute stroke treatment had increased odds for MMI of 1.57 [95% confidence interval (CI) 1.49-1.65]. In contrast, after treatment with IV-TPA, only we observed an OR of 0.88 (95% CI 0.83-0.94, p < 0.001), and after EVT an OR of 0.80 (95% CI 0.76-0.85, p < 0.001). This was more pronounced in larger pretreatment infarctions (ASPECTS < 5, p < 0.01). IV-TPA also lowers the MMI rates but not to the same extent. EVT-treated patients had increased survival rates (p < 0.05) and the best functional outcome at discharge.Conclusions: The findings of this study illustrate that occurrence of MMI and mortality rates was significantly reduced in patients treated with EVT. [ABSTRACT FROM AUTHOR]

Objective: Oral anticoagulation treatment (OAT) resumption is a therapeutic dilemma in intracerebral hemorrhage (ICH) care, particularly for lobar hemorrhages related to amyloid angiopathy. We sought to determine whether OAT resumption after ICH is associated with long-term outcome, accounting for ICH location (ie, lobar vs nonlobar).Methods: We meta-analyzed individual patient data from: (1) the multicenter RETRACE study (n = 542), (2) a U.S.-based single-center ICH study (n = 261), and (3) the Ethnic/Racial Variations of Intracerebral Hemorrhage study (n = 209). We determined whether, within 1 year from ICH, OAT resumption was associated with: (1) mortality, (2) favorable functional outcome (modified Rankin Scale = 0-3), and (3) stroke incidence. We separately analyzed nonlobar and lobar ICH cases using propensity score matching and Cox regression models.Results: We included 1,012 OAT-related ICH survivors (633 nonlobar and 379 lobar). Among nonlobar ICH survivors, 178/633 (28%) resumed OAT, whereas 86/379 (23%) lobar ICH survivors did. In multivariate analyses, OAT resumption after nonlobar ICH was associated with decreased mortality (hazard ratio [HR] = 0.25, 95% confidence interval [CI] = 0.14-0.44, p < 0.0001) and improved functional outcome (HR = 4.22, 95% CI = 2.57-6.94, p < 0.0001). OAT resumption after lobar ICH was also associated with decreased mortality (HR = 0.29, 95% CI = 0.17-0.45, p < 0.0001) and favorable functional outcome (HR = 4.08, 95% CI = 2.48-6.72, p < 0.0001). Furthermore, OAT resumption was associated with decreased all-cause stroke incidence in both lobar and nonlobar ICH (both p < 0.01).Interpretation: These results suggest novel evidence of an association between OAT resumption and outcome following ICH, regardless of hematoma location. These findings support conducting randomized trials to explore risks and benefits of OAT resumption after ICH. Ann Neurol 2017;82:755-765. [ABSTRACT FROM AUTHOR]

Background: Severe cerebral venous-sinus thrombosis (CVT) is a rare disease, and its clinical course, imaging correlates, as well as long-term prognosis have not yet been investigated systematically.Methods: Multicenter retrospective study. Inclusion criteria were CVT, Glasgow coma scale ≤9, and treatment in the intensive care unit. Primary outcome was death or dependency, assessed by a modified Rankin Score (mRS) >2 at last follow-up.Results: 114 patients were included. At last follow-up (median 2.5 years), 38 patients (33.3 %) showed no or minor residual symptoms (mRS = 0 or 1), 12 (10.5 %) had a mild (mRS = 2), 13 (11.4 %) a moderate (mRS = 3), 12 (10.5 %) a severe disability (mRS = 4 or 5), and 39 (34.2 %) had died. In bivariate analysis, predictors of poor outcome were any signs of mass effect on imaging, clinical deterioration after admission, and age. In contrast, clinical symptoms on admission and parenchymal lesions per se, such as edema, infarction, or hemorrhage were not predictive. Multivariate predictors of poor outcome were an increase in National Institutes of Health Stroke Scale ≥3 after admission [odds ratio (OR) 6.7], bilateral motor signs in the further course (OR 9.2), and midline shift (OR 5.1).Conclusion: The outcome of severe CVT is almost equally divided between severe impairment or death and survival with no or only mild handicap. Specifically, space-occupying mass effect and associated neurologic deterioration seem to determine a poor outcome. Therefore, early detection and treatment of mass effect should be the focus of critical care. [ABSTRACT FROM AUTHOR]

Background: Clostridium septicum is a rare cause of meningitis and brain abscess in children and adults. Gas production by the pathogen can lead to pneumocephalus and the overall mortality rate of Clostridium septicum CNS infection is as high as 74%. The most common entry site of the pathogen is the gastrointestinal tract. Case presentation: We describe a 74-year-old man who presented with a left-sided cerebral infarction in the middle cerebral artery territory. In addition the patient showed signs of Systemic Inflammatory Response Syndrome and Disseminated Intravascular Coagulation. Examination of blood cultures and cerebrospinal fluid led to the diagnosis of sepsis and meningitis caused by Clostridium septicum. Despite appropriate antibiotic therapy the condition of the patient deteriorated rapidly and he died on day 2 after admission. Autopsy revealed a previously unknown adenocarcinoma of the colon ascendens as entry site of the pathogen. Conclusion: Clostridium septicum should be considered as potential pathogen in patients with sepsis and meningitis. Gram stain morphology in conjunction with severe sepsis can rapidly point into the direction of this pathogen. CNS infections manifest either as meningoencephalitis/cerebritis or as brain abscess. Entry site of the pathogen is almost uniquely the gastrointestinal tract. In adults more than 50% suffer from colorectal carcinoma, therefore survivors of Clostridium septicum infections should be examined for underlying occult colorectal malignancy. [ABSTRACT FROM AUTHOR]