Objective:To investigate the efficacy and safety of precise mechanical thrombectomy based on ABC 2D scale in acute intracranial large artery occlusion stroke (ALVOs). Methods:A prospective study was performed. Two hundred and two patients with ALVOs accepted early mechanical thrombectomy in Department of Neurology, Maoming Clinical School of Guangdong Medical University from January 2021 to February 2022 were enrolled. They were randomly divided into experimental group ( n=102) and control group ( n=100). Stent retriever partially retracted with intermediate catheter for mechanical thrombectomy (SWIM) was the first choice for patients in control group. ABC 2D scale was used to prejudge the pathogenesis of patients in experimental group: patients with scores of 0-3 were considered as having embolic occlusion and a direct aspiration first pass technique (ADAPT) was the first choice, and SWIM would be chosen if suction catheter could not be in place; patients with scores of 4-7 were considered as having intracranial atherosclerotic stenosis occlusion and SWIM was the first choice. The clinical data, surgical effectiveness, surgical safety, and good prognosis rate 90 d after mechanical thrombectomy (modified Rankin scale scores of 0-2 as good prognosis) of the 2 groups were compared. Results:Experimental group had significantly shorter time from puncture to recanalization (51.0[35.0, 78.5] min vs. 67.0[45.0, 100.0] min), and statistically lower NIHSS scores 24 h after mechanical thrombectomy (10.00[4.75, 16.25] vs. 13.00[8.00, 19.00]), significantly higher good prognosis rate 90 d after mechanical thrombectomy (69.6% vs. 46.0%), statistically lower mortality 90 d after mechanical thrombectomy (3.9% vs. 13.0%) compared with control group ( P<0.05). No significant differences were noted in first-pass effect rate, successful vascular revascularization rate, or incidences of symptomatic intracranial hemorrhage (sICH) and ectopic embolization between the control group and experimental group ( P>0.05). Conclusion:Patients with ALVOs accepted early mechanical thrombectomy can have shorter time from puncture to vascular recanalization and better prognosis after etiologically prejudging by ABC 2D scale for thrombectomy.

Objective:To compare the optimal conditions, virus yield, viral titer and cell metabolism between culturing influenza virus H1N1 vaccine strain in MDCK and MDCK-G1 cells.Methods:The optimal culture conditions were investigated using chessboard method. The hemagglutination titer, half of the tissue infection dose (TCID 50) and the metabolism of glucose and lactic acid were monitored and compared between the two cell lines. Results:After MDCK-G1 cells were inoculated with H1N1 at the multiplicity of infection (MOI) of 0.001 with the presence of 1 μg/ml of trypsin, the hemagglutination titer reached the peak of 1∶512 at 72 h and the viral titer was 10 7.4TCID 50/ml. In the MDCK cell line group, the hemagglutination titer reached the peak of 1∶256 at 72 h and the viral titer was 10 6.6TCID 50/ml when using H1N1 at MOI=0.0001 and 1 μg/ml of trypsin. Conclusions:MDCK-G1 cells were more suitable than MDCK cells for the proliferation of influenza virus. This study provided reference data for further research on cell-derived influenza vaccine.