Methylprednisolone as Adjunct to Endovascular Thrombectomy for Large-Vessel Occlusion Stroke

Importance It is uncertain whether intravenous methylprednisolone improves outcomes for patients with acute ischemic stroke due to large-vessel occlusion (LVO) undergoing endovascular thrombectomy. Objective To assess the efficacy and adverse events of adjunctive intravenous low-dose methylprednisolone to endovascular thrombectomy for acute ischemic stroke secondary to LVO. Design, Setting, and Participants This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 82 hospitals in China, enrolling 1680 patients with stroke and proximal intracranial LVO presenting within 24 hours of time last known to be well. Recruitment took place between February 9, 2022, and June 30, 2023, with a final follow-up on September 30, 2023.InterventionsEligible patients were randomly assigned to intravenous methylprednisolone (n = 839) at 2 mg/kg/d or placebo (n = 841) for 3 days adjunctive to endovascular thrombectomy. Main Outcomes and Measures The primary efficacy outcome was disability level at 90 days as measured by the overall distribution of the modified Rankin Scale scores (range, 0 [no symptoms] to 6 [death]). The primary safety outcomes included mortality at 90 days and the incidence of symptomatic intracranial hemorrhage within 48 hours. Results Among 1680 patients randomized (median age, 69 years; 727 female [43.3%]), 1673 (99.6%) completed the trial. The median 90-day modified Rankin Scale score was 3 (IQR, 1-5) in the methylprednisolone group vs 3 (IQR, 1-6) in the placebo group (adjusted generalized odds ratio for a lower level of disability, 1.10 [95% CI, 0.96-1.25]; P = .17). In the methylprednisolone group, there was a lower mortality rate (23.2% vs 28.5%; adjusted risk ratio, 0.84 [95% CI, 0.71-0.98]; P = .03) and a lower rate of symptomatic intracranial hemorrhage (8.6% vs 11.7%; adjusted risk ratio, 0.74 [95% CI, 0.55-0.99]; P = .04) compared with placebo. Conclusions and Relevance Among patients with acute ischemic stroke due to LVO undergoing endovascular thrombectomy, adjunctive methylprednisolone added to endovascular thrombectomy did not significantly improve the degree of overall disability.Trial RegistrationChiCTR.org.cn Identifier: ChiCTR210005172

Investigation of Strain Fatigue Behavior for Inconel 625 with Laser Shock Peening

With excellent creep resistance, high-temperature thermal strength and high-temperature fatigue strength, Inconel 625 is widely applied to fabricate structural components in the aerospace field, where fatigue life is a key point. Laser shock peening (LSP) is considered to improve the fatigue strength and fatigue crack growth resistance of metal materials. The present work was conducted to investigate the influence of LSP on strain-controlled fatigue behavior of Inconel 625. The surface microstructures of specimens before and after LSP were observed by transmission electron microscope (TEM). The strain-controlled fatigue loading tests with different strain amplitudes ranging from 0.4% to 1.2% were carried out on the specimens, and the topography of fracture appearance was examined by scanning electron microscope (SEM). The investigations showed that the specimens with LSP presented fewer crack initiations, shorter fatigue striations space and smaller dimples or micropores, which account for the enhancement of the fatigue life for the LSP specimens. Furthermore, the plastic deformation, ultra-fine grains, twins and dislocations caused by LSP could prevent crack initiation, crack propagation and ultimate fracture, hence prolonging the fatigue life of the Inconel 625. In addition, it was revealed that the cyclic strain hardening as well as cyclic strain softening remains almost the same to Inconel 625 with or without LSP

Robust UKF algorithm with motion constraint in BDS navigation

In a complex urban environment,navigation based on single BeiDou navigation satellite system (BDS) will be interfered by multipath (MP) and non-line-of-sight (NLOS) signals, which degrades the accuracy of positioning. In order to solve this problem, a robust unscented Kalman filter (UKF) with motion constraint is proposed. The algorithm constructs an equivalent weight function based on the innovation vector, which will overcome the problem of performance degradation of conventional robust method caused by inaccurate initial values of the position and receiver clock offset. In addition, the approximate moving direction and elevation of the carrier are used to further enhance the filtering solution. The actual on-board experiment results show that this method can effectively suppress the interference of MP and NLOS signals, and improve the accuracy of BDS navigation in urban environments

Consolidation-acidizing experiments on methane natural gas sediment skeleton

During the development of natural gas hydrates, it is important to ensure the stability of the reservoir. The hydrate reservoirs in the South China Sea are clayey silt sediments, which are prone to sand production and collapse during hydrate dissociation. This study innovatively proposes the idea of consolidation-acidizing for NGH reservoir modification. Based on the core parameters of well A drilling in the Shenhu Sea area of the South China Sea, NGH sediment skeleton samples were artificially prepared. Core sensitivity testing indicates that the NGH reservoir has the potential for acidizing modification. After using tetraethyl orthosilicate to solidify the sample, it was found that Young’s modulus of the sample increased by 58.8%, and the compressive strength increased by 54.78%. Although the porosity decreased by 39.33%, the pores were not completely blocked. After the acidizing experiment, the permeability of the consolidated sample was 2.88 mD, and the porosity increased by 10.63%; The permeability of the unconsolidated sample was 1.86 mD, and the porosity decreased by 10.73%. The CT scan images also showed that the pores of the sample after consolidation-acidizing developed uniformly without significant deformation; The unconsolidated sample undergoes severe deformation and sand production after acidizing. This study demonstrates that the consolidation-acidizing modification method is feasible in clayey silt hydrate reservoirs

Survival Benefits of Radiotherapy and Surgery in Lung Cancer Brain Metastases with Poor Prognosis Factors

Background: Radiotherapy and surgery are the standard local treatments for lung cancer brain metastases (BMs). However, limited studies focused on the effects of radiotherapy and surgery in lung cancer BMs with poor prognosis factors. Methods: We retrospectively analyzed 714 patients with lung cancer BMs. Analyses of overall survival (OS) and risk factors for OS were assessed by the log-rank test and Cox proportional hazard model. Results: Age ≥ 65 years, a Karnofsky Performance Scale (KPS) score ≤ 70, anaplastic large-cell lymphoma kinase (ALK)/epidermal growth factor receptor (EGFR) wild type, and extracranial metastases were related to poor prognosis. Patients were stratified according to these poor prognosis factors. In patients with the ALK/EGFR wild type, whole brain radiotherapy (WBRT), stereotactic radiosurgery (SRS), and surgery improved the OS of patients. WBRT and SRS were the independent protective factors for OS. In patients with extracranial metastases, patients who received WBRT plus SRS or WBRT alone had longer OS than those who did not receive radiotherapy. WBRT plus SRS and WBRT were the independent protective factors for OS. Conclusions: Radiotherapy and surgery are associated with improved survival for lung cancer BMs with the ALK/EGFR wild type. Radiotherapy is associated with improved survival in lung cancer BMs with extracranial metastases

The MicroArray Quality Control (MAQC)-II study of common practices for the development and validation of microarray-based predictive models

Gene expression data from microarrays are being applied to predict preclinical and clinical endpoints, but the reliability of these predictions has not been established In the MAQC II project, 36 independent teams analyzed six microarray data sets to generate predictive models for classifying a sample with respect to one of 13 endpoints indicative of lung or liver toxicity in rodents, or of breast cancer, multiple myeloma or neuroblastoma in humans In total, &gt;30,000 models were built using many combinations of analytical methods The teams generated predictive models without knowing the biological meaning of some of the endpoints and, to mimic clinical reality, tested the models on data that had not been used for training We found that model performance depended largely on the endpoint and team proficiency and that different approaches generated models of similar performance The conclusions and recommendations from MAQC-II should be useful for regulatory agencies, study committees and independent investigators that evaluate methods for global gene expression analysis</span