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The microstructure, corrosion resistance and mechanical properties of extruded pure Mg, Mg-2Y and Mg-2Gd were studied by means of scanning electron microscope (SEM), X-ray diffraction (XRD), electron backscatter diffraction (EBSD), scanning probe microscope (SPM), immersion test, electrochemical test and tensile test. The results demonstrated that Mg-2Y and Mg-2Gd were composed of Mg, Mg24Y5, and Mg5Gd phases with the addition of Y and Gd. The addition of Y and Gd to pure Mg noticeably reduced the grain size and textural strength of the alloy. Mg-2Gd alloy had the smallest grain size and the lowest textural strength. The corrosion rate of Mg-2Gd was the slowest due to the influence of grain size. Y slowed the corrosion of pure Mg in the early stages due to the grain refinement, but speeded up the corrosion because of the galvanic corrosion produced by the precipitation of the second phase in the latter stages. The elongation of pure Mg, Mg-2Y, and Mg-2Gd were 16.5 %, 38.67 %, and 48.67 %, respectively. The inclusion of Y and Gd refined the grain, softened the texture strength, and activated basal slip, which improved the elasticity of alloys. Gd was more significant than Y in improving the corrosion resistance and mechanical properties of pure Mg.
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BACKGROUND: This study aimed to evaluate the efficacy and safety of adjuvant tirofiban in patients with acute basilar artery occlusion due to large-artery atherosclerotic (LAA) receiving endovascular therapy (EVT). METHODS: This was a non-randomized, multicenter study using data from the Endovascular Treatment for Acute BASILAR Artery Occlusion (BASILAR) registry. Patients with acute basilar artery occlusion due to LAA within 24h of symptom onset who underwent EVT were included. Patients were divided into tirofiban and non-tirofiban groups according to whether tirofiban was used. The primary outcome was the ordinal modified Rankin scale score at 90 days. Safety outcomes were mortality within 90 days and symptomatic intracranial hemorrhage (sICH) within 48 h. RESULTS: A total of 417 patients were included, of whom 275 patients were in the tirofiban group and 142 patients in the non-tirofiban group. Compared with patients in the non-tirofiban group, patients in the tirofiban group were associated with a favorable shift in functional outcome at 90 days (6[4-6] vs 5 [2-6]; adjusted common OR, 2.51; 95 % CI, 1.64-3.83). The mortality was lower in the tirofiban group than the non-tirofiban group (40.7 % vs 58.5 %; adjusted OR, 0.35; 95 % CI, 0.21-0.56). The rate of sICH was 12.2 % in the non-tirofiban group and 5.2 % in the tirofiban group (adjusted OR, 0.37; 95 % CI, 0.17-0.80; P = 0.012). CONCLUSION: Tirofiban plus EVT might improve functional outcomes with a good safety for patients with acute basilar artery occlusion due to LAA. The results need to be confirmed in a randomized trial.
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Aterosclerose , Isquemia Encefálica , Procedimentos Endovasculares , Acidente Vascular Cerebral , Humanos , Tirofibana/efeitos adversos , Artéria Basilar/diagnóstico por imagem , Isquemia Encefálica/diagnóstico , Resultado do Tratamento , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Aterosclerose/etiologia , Hemorragias Intracranianas/induzido quimicamente , Trombectomia/efeitos adversosRESUMO
BACKGROUND AND OBJECTIVE: To investigate the efficacy and safety of IV infusion of tirofiban before endovascular thrombectomy for patients with large vessel occlusion due to intracranial atherosclerotic disease. The secondary objective was to identify potential mediators for the clinical effect of tirofiban. METHODS: Post hoc exploratory analysis of the Endovascular Treatment With versus Without Tirofiban for Patients with Large Vessel Occlusion Stroke (RESCUE BT) trial, which was a randomized, double-blinded, placebo-controlled trial at 55 centers in China from October 2018 to October 2021. Patients with occlusion of the internal carotid artery or middle cerebral artery due to intracranial atherosclerosis were included. The primary efficacy outcome was the proportion of patients achieving functional independence (defined as modified Rankin scale 0-2) at 90 days. Binary logistic regression and causal mediation analyses were used to estimate the treatment effect of tirofiban and the potential mediators. RESULTS: This study included 435 patients, of whom 71.5% were men. The median age was 65 (interquartile range [IQR] 56-72) years, with a median NIH Stroke Scale of 14 (IQR 10-19). Patients in the tirofiban group had higher rates of functional independence at 90 days than patients in the placebo group (adjusted odds ratio 1.68; 95% CI 1.11-2.56, p = 0.02) without an increased risk of mortality or symptomatic intracranial hemorrhage. Tirofiban was associated with fewer thrombectomy passes (median [IQR] 1 [1-2] vs 1 [1-2], p = 0.004), which was an independent predictor of functional independence. Mediation analysis showed tirofiban-reduced thrombectomy passes explained 20.0% (95% CI 4.1%-76.0%) of the effect of tirofiban on functional independence. DISCUSSION: In this post hoc analysis of the RESCUE BT trial, tirofiban was an effective and well-tolerated adjuvant medication of endovascular thrombectomy for patients with large vessel occlusion due to intracranial atherosclerosis. These findings need to be confirmed in future trials. TRIAL REGISTRATION INFORMATION: The RESCUE BT trial was registered on the Chinese Clinical Trial Registry: chictr.org.cn, ChiCTR-INR-17014167. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that tirofiban plus endovascular therapy improves 90-day outcome for patients with large vessel occlusion due to intracranial atherosclerosis.
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Isquemia Encefálica , Procedimentos Endovasculares , Arteriosclerose Intracraniana , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Tirofibana/uso terapêutico , Tirofibana/efeitos adversos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , AVC Isquêmico/tratamento farmacológico , Resultado do Tratamento , Trombectomia/efeitos adversos , Arteriosclerose Intracraniana/tratamento farmacológico , Procedimentos Endovasculares/efeitos adversos , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/cirurgiaRESUMO
Background: parenchymal hematoma (PH) is a severe complication of endovascular treatment (EVT) for acute basilar artery occlusion (ABAO). This study aimed to evaluate the incidence and predictors of PH after EVT for ABAO. Methods: Using data from the Endovascular Treatment for Acute Basilar Artery Occlusion Study, we enrolled patients treated with mechanical thrombectomy from the BASILAR registry. PH was assessed in accordance with the Heidelberg Bleeding Classification. Logistic regression was used to identify predictors of PH. Results: A total of 639 patients were included. Forty-eight patients (7.5%) were diagnosed with PH within 48 h of EVT. Ninety-day mortality was higher in patients with PH compared with those without (81.3 vs. 42.8%, P < 0.001). Favorable neurological outcomes (modified Rankin scale score, 0-3) rates was lower in patients with PH compared with those without (6.3 vs. 34.5%, P < 0.001). With a multivariate analysis, hypertension [odds ratio (OR) = 2.30, 95% confidence interval (CI) 1.04-5.08], pre-treatment National Institutes of Health Stroke Score (NIHSS, >25; OR = 3.04, 95% CI 1.43-6.45), and Neutrophil-to-lymphocyte ratio (NLR, >10; OR = 1.88, 95% CI 1.02-3.48) were associated with PH after EVT. Conclusions: PH occurred at a rate of 7.5% after EVT in patients with ABAO. Hypertension, higher baseline NIHSS, and higher NLR value increase the risk of PH after EVT for ABAO.
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By using glycidol as a catalyst, high porosity, low-density resorcinol (R) and formaldehyde (F) aerogels and carbon aerogels (CAs) were synthesized via a sol-gel method. The effect of glycidol and water on the color, density, morphology, textual characteristics and adsorption properties of the resultant RF aerogels and CAs were investigated in detail. The results revealed that the properties of RF aerogels and CAs can be controlled by adjusting the amount of glycidol and water. The resultant RF aerogels and CAs were porous materials, the minimum densities of RF aerogels and CAs were 96 and 110 mg cm-3 respectively while the maximum specific surface areas of RF aerogels and CAs were 290 and 597 m2 g-1. The maximum adsorption capacity of CAs was about 125 mg g-1 on Rhodamine B, which was higher than that of some reported CAs catalyzed by base and acid catalysts. The sol-gel mechanisms of RF aerogels and CAs can be attributed to the opening of the epoxy group of glycidol in the mixture of R and F.
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Importance: Tirofiban is a highly selective nonpeptide antagonist of glycoprotein IIb/IIIa receptor, which reversibly inhibits platelet aggregation. It remains uncertain whether intravenous tirofiban is effective to improve functional outcomes for patients with large vessel occlusion ischemic stroke undergoing endovascular thrombectomy. Objective: To assess the efficacy and adverse events of intravenous tirofiban before endovascular thrombectomy for acute ischemic stroke secondary to large vessel occlusion. Design, Setting, and Participants: This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 55 hospitals in China, enrolling 948 patients with stroke and proximal intracranial large vessel occlusion presenting within 24 hours of time last known well. Recruitment took place between October 10, 2018, and October 31, 2021, with final follow-up on January 15, 2022. Interventions: Participants received intravenous tirofiban (n = 463) or placebo (n = 485) prior to endovascular thrombectomy. Main Outcomes and Measures: The primary outcome was disability level at 90 days as measured by overall distribution of the modified Rankin Scale scores from 0 (no symptoms) to 6 (death). The primary safety outcome was the incidence of symptomatic intracranial hemorrhage within 48 hours. Results: Among 948 patients randomized (mean age, 67 years; 391 [41.2%] women), 948 (100%) completed the trial. The median (IQR) 90-day modified Rankin Scale score in the tirofiban group vs placebo group was 3 (1-4) vs 3 (1-4). The adjusted common odds ratio for a lower level of disability with tirofiban vs placebo was 1.08 (95% CI, 0.86-1.36). Incidence of symptomatic intracranial hemorrhage was 9.7% in the tirofiban group vs 6.4% in the placebo group (difference, 3.3% [95% CI, -0.2% to 6.8%]). Conclusions and Relevance: Among patients with large vessel occlusion acute ischemic stroke undergoing endovascular thrombectomy, treatment with intravenous tirofiban, compared with placebo, before endovascular therapy resulted in no significant difference in disability severity at 90 days. The findings do not support use of intravenous tirofiban before endovascular thrombectomy for acute ischemic stroke. Trial Registration: Chinese Clinical Trial Registry Identifier: ChiCTR-IOR-17014167.
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Procedimentos Endovasculares , AVC Isquêmico , Inibidores da Agregação Plaquetária , Trombectomia , Tirofibana , Administração Intravenosa , Idoso , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/tratamento farmacológico , Arteriopatias Oclusivas/cirurgia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Isquemia Encefálica/cirurgia , Método Duplo-Cego , Procedimentos Endovasculares/métodos , Feminino , Humanos , Hemorragias Intracranianas/induzido quimicamente , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/etiologia , AVC Isquêmico/cirurgia , Masculino , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Tirofibana/administração & dosagem , Tirofibana/efeitos adversos , Tirofibana/uso terapêutico , Resultado do TratamentoRESUMO
In this work, Mg-3Y sheet was prepared by high temperature cross-rolling and subsequent short-term annealing. The effect of annealing on microstructure, texture, mechanical properties, and stretch formability of Mg-3Y sheet was primarily investigated. Micro-nano size coexistence of ß-Mg24Y5 phases can be well deformed with matrix. The as-rolled Mg-3Y sheet exhibited a homogeneous deformation microstructure consisting of deformed grains with extensive kink bands and dispersed ß-Mg24Y5 phases. A double peak texture character appeared in as-rolled Mg-3Y sheet with a split of the texture peaks of about ±20° tilted to rolling direction. After annealing, the as-annealed Mg-3Y sheet presented complete static recrystallized (SRXed) microstructure consisting of uniform equiaxed grains. The texture orientation distribution was more dispersed and a weakened multiple-peak texture orientation distribution appeared. In addition, the maximum intensity of basal plane decreased from 5.2 to 3.1. The change of texture character was attributed to static recrystallization (SRX) induced by kink bands and grain boundaries. The as-annealed Mg-3Y sheet with high Schmid factor (SF) for basal slip, prismatic slip, pyramidal slip, and pyramidal
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INTRODUCTION: This study aimed to investigate clinical outcomes in young patients with basilar artery occlusion (BAO) receiving endovascular therapy (EVT). METHODS: Consecutive patients with BAO within 24 h who underwent EVT from the BASILAR Registry study were enrolled. We compared clinical outcomes of young patients (aged 18-55 years) with older patients (aged > 55 years) with stroke due to BAO at 90 days and 1 year after EVT. The primary and secondary outcomes were improvement in modified Rankin scale scores (mRS) at 90 days and either favorable (mRS 0-3) or mortality at 90 days, respectively. RESULTS: A total of 646 patients were included, of which 152 (23.53%) were aged 18-55 years. Dyslipidemia (42.11% vs. 30.36%, p = 0.007) and good collateral circulation (60.52% vs. 46.35%, p = 0.002) were more frequent in young patients than older. Stroke etiologies in young patients included large artery atherosclerosis (67.11%), cardioembolism (15.13%), and vessel dissection (5.26%). Young patients were associated with better prognosis (mRS: adjusted odds ratio (aOR) 1.73; 95% confidence interval [CI] 1.21-2.48; mRS 0-3: aOR 1.60; 95% CI 1.01-2.54; mortality: aOR 0.60; 95% CI 0.38-0.93) at 90 days. Baseline National Institutes of Health Stroke Scale (NIHSS) score, posterior circulation Alberta Stroke Program Early Computed Tomography Score (pc-ASPECTS), and sex were independent predictors of clinical outcomes of young patients at 90 days after EVT. CONCLUSION: Young patients with BAO had better clinical outcomes after EVT than old patients. Predictors of clinical outcomes in young patients undergoing EVT included baseline NIHSS score, pc-ASPECTS, and sex. TRIAL REGISTRATION: Clinical Trial Registration-URL: ChiCTR180001475 ( www.chictr.org.cn ).
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Background: A link between body temperature and stroke outcomes has been established but not for acute basilar artery occlusion. We aimed to determine the association between body temperature and clinical outcomes in patients with acute basilar artery occlusion and temperature management range. Methods: We included patients from the Endovascular Treatment for Acute Basilar Artery Occlusion Study (BASILAR) database with records of both admission body temperature (ABT) and peak body temperature (PBT). ABT was defined as the body temperature first measured at the hospital visit, PBT was defined as the highest temperature within 24 h of treatment, and minus body temperature (MBT) was defined as PBT-ABT. The primary clinical outcome was favorable functional outcome, defined as the proportion of patients with a modified Rankin Scale score of 0-3 at 3 months. Secondary outcomes included 3-month mortality, in-hospital mortality, and symptomatic cerebral hemorrhage. Results: A total of 664 patients were enrolled in the study; 74.7% were men, with a median age of 65 (interquartile range, 57.25-74) years. In all patients, multivariate analysis indicated that PBT and MBT were independent predictors of favorable functional outcome [odds ratio (OR), 0.57 (95% CI, 0.43-0.77); OR, 0.68 (95% CI, 0.52-0.88), respectively], and higher ABT, PBT, and MBT were associated with an increased 3-month mortality [OR, 1.47 (95% CI, 1.03-2.10), OR, 1.58 (95% CI, 1.28-1.96), OR, 1.35 (95% CI, 1.11-1.65), respectively]. Proportional odds models demonstrated that when ABT, PBT, MBT were in the range of <37.5, <38.9, and -0.6-2.7°C, respectively, the benefit of the endovascular treatment is clearly greater than that of standard medical treatment in terms of favorable functional outcome. Conclusions: Body temperature is an independent predictor of clinical outcome in patients with acute basilar artery occlusion. It is necessary to control the patient body temperature within the appropriate range in clinical settings. Trial Registration: Chinese Clinical Trial Registry ChiCTR1800014759. Registered 03 February 2018. Retrospectively registered.
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Nonradical oxidation based on singlet oxygen (1O2) has attracted great interest in groundwater remediation due to the selective oxidation property and good resistance to background constituents. Herein, recoverable CuO nanoparticles (NPs) supported on mineral substrates (SiO2) were prepared by calcination of surface-coated metal-plant phenolic networks and explored for peroxymonosulfate (PMS) activation to generate 1O2 for degrading organic pollutants in groundwater. CuO NPs with a close particle size (40 nm) were spatially monodispersed on SiO2 substrates, allowing highly exposure of active sites and consequently leading to outstanding catalytic performance. Efficient removal of various organic pollutants was obtained by the supported CuO NPs/PMS system under wide operation conditions, e.g., working pH, background anions and natural organic matters. Chemical scavenging experiments, electron paramagnetic resonance tests, furfuryl alcohol decay and solvent dependency experiments confirmed the formation of 1O2 and its dominant role in pollutants removal. In situ characterization with ATR-FTIR and Raman spectroscopy and computational calculation revealed that a redox cycle of surface Cu(II)-Cu(III)-Cu(II) was responsible for the generation of 1O2. The feasibility of the supported CuO NPs/PMS for actual groundwater remediation was evaluated via a flow-through test in a fixed-bed column, which manifested long-term durability, high mineralization ratio and low metal ion leaching.
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ZnSe has got extensive attention for high-performance LIBs anode due to its remarkable theoretical capacity and environmental friendliness. Nevertheless, the large volume variation for the ZnSe in the discharge/charge processes brings about rapid capacity fading and poor rate performance. Herein, ZnSe/C hollow polyhedrons are successfully synthesized by selenization of zeolitic imidazolate framework-8 (ZIF-8) with resorcinol-formaldehyde (RF) coating. The protection of C layer derived from RF coating layer and Ostwald ripening during the process of selenization play important roles in promoting formation of ZnSe/C hollow polyhedrons. The ZnSe/C hollow polyhedrons exhibit good rate performance and long-term cycle stability (345â mAh g-1 up to 1000 cycles at 1â A g-1 ) for lithium ion batteries (LIBs) anode. The improved electrochemical performance is benefit from the unique ZnSe/C hollow structure, in which the hollow structure can effectively avoid terrible volume expansion, and the thin ZnSe/C shell can not only provide adequate diffusion paths of lithium ions and but also enhance the electronic conductivity.