Objective To investigate the effect of inhibition of glycogen synthase kinase?3 beta ( GSK?3β) activity on sevoflurane postconditioning?induced cardioprotection in diabetic rats. Methods Healthy adult male Sprague?Dawley rats, weighing 250-300 g, in which diabetes mellitus was induced by intraperitoneal 1% streptozotocin 60 mg∕kg combined with high?fat and high?sucrose diet and confirmed by blood glucose level >16. 7 mmol∕L. Forty rats with diabetes mellitus were divided into 5 groups ( n=8 each) using a random number table: sham operation group ( S group ) , ischemia?reperfusion ( I∕R ) group, sevoflurane postconditioning group ( SP group) , GSK?3β inhibitor SB216763 group ( SB group) , and sevoflurane postconditioning plus SB216763 group ( SS group ) . Myocardial ischemia was induced by 30 min occlusion of the left anterior descending branch of the coronary artery followed by 120 min reperfu?
sion. The rats inhaled sevoflurane with the end?tidal concentration of 2.5% for 5 min starting from 1 min be?fore reperfusion in group SP. SB216763 0.2 mg∕kg was injected via the caudal vein at 1 min before reperfu?sion in group SB. In group SS, the rats inhaled sevoflurane with the end?tidal concentration of 2.5% for 5 min starting from 1 min before reperfusion, and SB216763 0.2 mg∕kg was injected via the caudal vein at 1 min before reperfusion. At 120 min of reperfusion, blood samples were collected from the carotid artery for determination of serum creatine kinase?MB (CK?MB) activity and cardiac troponin I (cTnI) concentra?tions. Myocardial specimens were collected at 120 min of reperfusion for microscopic examination of the pathological changes and for determination of myocardial infarct size ( by 2,3,5?triphenyltetrazolium chlo?ride staining) and phosphorylated GSK?3β (p?GSK?3β) expression (by Western blot). Results Com?pared with group S, the myocardial infarct size and serum CK?MB activity and cTnI concentration were sig?nificantly increased, and the expression of p?GSK?3βwas significantly down?regulated in I∕R, SP, SB and SS groups (P<0.05). Compared with group I∕R, the myocardial infarct size and serum CK?MB activity and cTnI concentration were significantly decreased, and the expression of p?GSK?3β was significantly up?regulated in SB and SS groups (P<0.05), and no significant change was found in the parameters men?tioned above in group SP ( P>0.05) . Compared with group SB, the myocardial infarct size and serum CK?MB activity and cTnI concentration were significantly decreased, and the expression of p?GSK?3β was sig?nificantly up?regulated in group SS (P<0.05). The pathological changes of myocardium were significantly attenuated in SB and SS groups as compared with group I∕R and group SP . Conclusion Inhibition of GSK?3β activity can improve sevoflurane postconditioning?induced cardioprotection in diabetic rats.

Objective:To analysis effectiveness of the "14 plus 7 day quarantine" and "nucleic acid plus total antibody testing" strategy (combined screening strategy) for screenin the imported patients with COVID-19 in Xiamen.Methods:The study populations were overseas travelers arriving in Xiamen from March 17 to December 31, 2020, and overseas travelers who had quarantine outside Xiamen for less than 21 days from July 18 to December 31, 2020. Data were collected and analyzed on the timing of detection, pathways, and test results of the imported patients with COVID-19 after implementing combined screening strategy.Results:A total of 304 imported patients with COVID-19 were found from 174 628 overseas travelers and 943 overseas travelers from other cities. A total of 163 cases (53.6%) were diagnosed by multitime, multisite intensive nucleic acid testing after positive finding in total antibody testing. Among them, 27 (8.9%) were first positive for nucleic acid in 14 plus 7 day quarantine and 136 were first positive for nucleic acid in 14-day quarantine. Only 8 of these individuals were tested positive for nucleic acid after positive total antibody testing. The other 128 individuals were tested positive for nucleic acid after being negative for average 2.3 times (maximum of 6 times). Aditional 155 cases might be detected by using the combined "14 plus 7 day quarantine" and " nucleic acid plus total antibody testing" strategy compared with "14-day quarantine and nucleic acid testing" strategy, accounting for 51.0% of the total inbound infections. So the combined screening strategy doubled the detection rate for imported patients with COVID-19. No second-generation case caused by overseas travelers had been reported in Xiamen as of February 26, 2021.Conclusions:Xiamen's combined screening strategy can effectively screen the imported patients with COVID-19 who were first positive for nucleic acid after 14 day quarantine. Compared with "14 day quarantine and nucleic acid testing", the combined screening strategy improved detection rate and further reduced the risk of the secondary transmission caused by the imported patients with COVID-19.

The velocity distribution,vortex evolution,viscous shear stress distribution and Reynolds shear stress distribution downstream of the aortic bileaflet mechanical heart valve are investigated under different physiological conditions using computational fluid dynamics method.At peak systole,the blood jet is more intense in the exercise state than in the other two states,with a maximum blood flow rate of 2.1 m/s.The analysis on vortex evolution shows that the shear layer is the obvious flow feature in the 3 physiological states and that the blood interacts more strongly with the aortic sinus at peak systole.For viscous shear stress,when the valve leaflets are fully open,the leaflets impede blood flow across the valve in the valvular region.The interaction between the blood flow and the valve leaflets results in high shear stress,and the maximum viscous shear stress observed in the 3 physiologic states is less than 8 N/m2.The maximum Reynolds shear stress observed in the 3 physiologic states is 700 N/m2.The study provides a theoretical basis for surgical valve selection and postoperative rehabilitation.