BACKGROUND Endoscopic mucosal dissection has become the standard treatment for early gastric cancer.However,post-endoscopic submucosal dissection(ESD)ulcer occurs in 4.4%of patients.This study hypothesized whether app...BACKGROUND Endoscopic mucosal dissection has become the standard treatment for early gastric cancer.However,post-endoscopic submucosal dissection(ESD)ulcer occurs in 4.4%of patients.This study hypothesized whether applying PuraStat,a novel hemostatic peptide solution,prevents post-ESD bleeding.AIM To investigate the preventive potential of PuraStat,a hemostatic formulation,against bleeding in post-ESD gastric ulcers.METHODS Between May 2022 and March 2023,101 patients(Group P)underwent ESD for gastric diseases at our hospital and received PuraStat(2 mL)for post-ESD ulcers.We retrospectively compared this group with a control group(Group C)com-prising 297 patients who underwent ESD for gastric diseases at our hospital between April 2017 and March 2021.P values<0.05 on two-sided tests indicated significance.RESULTS Post-ESD bleeding occurred in 6(5.9%)(95%CI:2.8-12.4)and 20(6.7%)(95%CI:4.4-10.2)patients in Groups P and C,respectively,with no significant between-group difference.The relative risk was 1.01(95%CI:0.95-1.07).The lesser curvature or anterior wall was the bleeding site in all 6 patients who experienced postoperative bleeding in Group P.In multivariate analysis,the odds ratios for resection diameter≥50 mm and oral anticoagulant use were 6.63(95%CI:2.52-14.47;P=0.0001)and 4.04(1.26-0.69;P=0.0164),respectively.The adjusted odds ratio of post-ESD bleeding and PuraStat was 1.28(95%CI:0.28-2.15).CONCLUSION PuraStat application is not associated with post-ESD bleeding.However,the study suggests that gravitational forces may affect the effectiveness of applied PuraStat.展开更多
The existing research for unsteady flow field and the corresponding flow induced vibration analysis of centrifugal pump are mainly carried out respectively without considering the interaction between fluid and structu...The existing research for unsteady flow field and the corresponding flow induced vibration analysis of centrifugal pump are mainly carried out respectively without considering the interaction between fluid and structure. The ignorance of fluid structure interaction （FSI） means that the energy transfer between fluid and structure is neglected. To some extent, the accuracy and reliability of unsteady flow and rotor deflection analysis should be affected by this interaction mechanism. In this paper, a combined calculation between two executables for turbulent flow and vibrating structure was established using two-way coupling method to study the effect of FSI. Pressure distributions, radial forces, rotor deflection and equivalent stress are analyzed. The results show that the FSI effect to pressure distribution in flow field is complex. The pressure distribution is affected not only around impeller outlet where different variation trends of pressure values with and without FSI appear according to different relative positions between blade and cutwater, but also in the diffusion section of volute. Variation trends of peak values of radial force amplitude calculated with and without FSI are nearly same under high flow rate and designed conditions while the peak value with FSI is slightly smaller, and differently, the peak value with FSI is larger with low flow rate. In addition, the effect of FSI on the angle of radial force is quite complex, especially under 0.5Q condition. Fluctuation of radial deflection of the rotor has obvious four periods, of which the extent is relatively small under design condition and is relatively large under off-design condition. Finally, fluctuations of equivalent stress with time are obvious under different conditions, and stress value is small. The proposed research establishes the FSI calculation method for centrifugal pump analysis, and ensures the existing affect by fluid structure interaction.展开更多
基金This study was reviewed and approved by the Showa University Institutional Review Board(2023-052-A).
文摘BACKGROUND Endoscopic mucosal dissection has become the standard treatment for early gastric cancer.However,post-endoscopic submucosal dissection(ESD)ulcer occurs in 4.4%of patients.This study hypothesized whether applying PuraStat,a novel hemostatic peptide solution,prevents post-ESD bleeding.AIM To investigate the preventive potential of PuraStat,a hemostatic formulation,against bleeding in post-ESD gastric ulcers.METHODS Between May 2022 and March 2023,101 patients(Group P)underwent ESD for gastric diseases at our hospital and received PuraStat(2 mL)for post-ESD ulcers.We retrospectively compared this group with a control group(Group C)com-prising 297 patients who underwent ESD for gastric diseases at our hospital between April 2017 and March 2021.P values<0.05 on two-sided tests indicated significance.RESULTS Post-ESD bleeding occurred in 6(5.9%)(95%CI:2.8-12.4)and 20(6.7%)(95%CI:4.4-10.2)patients in Groups P and C,respectively,with no significant between-group difference.The relative risk was 1.01(95%CI:0.95-1.07).The lesser curvature or anterior wall was the bleeding site in all 6 patients who experienced postoperative bleeding in Group P.In multivariate analysis,the odds ratios for resection diameter≥50 mm and oral anticoagulant use were 6.63(95%CI:2.52-14.47;P=0.0001)and 4.04(1.26-0.69;P=0.0164),respectively.The adjusted odds ratio of post-ESD bleeding and PuraStat was 1.28(95%CI:0.28-2.15).CONCLUSION PuraStat application is not associated with post-ESD bleeding.However,the study suggests that gravitational forces may affect the effectiveness of applied PuraStat.
基金supported by National Outstanding Young Scientists Founds of China (Grant No. 50825902)Jiangsu Provincial Innovative Scholars "Climbing" Project of China (Grant No. BK 2009006)+1 种基金National Natural Science Foundation of China (Grant No. 50979034)Jiangsu Provincial Project for Innovative Postgraduates of China (Grant No. CX10B_262Z)
文摘The existing research for unsteady flow field and the corresponding flow induced vibration analysis of centrifugal pump are mainly carried out respectively without considering the interaction between fluid and structure. The ignorance of fluid structure interaction （FSI） means that the energy transfer between fluid and structure is neglected. To some extent, the accuracy and reliability of unsteady flow and rotor deflection analysis should be affected by this interaction mechanism. In this paper, a combined calculation between two executables for turbulent flow and vibrating structure was established using two-way coupling method to study the effect of FSI. Pressure distributions, radial forces, rotor deflection and equivalent stress are analyzed. The results show that the FSI effect to pressure distribution in flow field is complex. The pressure distribution is affected not only around impeller outlet where different variation trends of pressure values with and without FSI appear according to different relative positions between blade and cutwater, but also in the diffusion section of volute. Variation trends of peak values of radial force amplitude calculated with and without FSI are nearly same under high flow rate and designed conditions while the peak value with FSI is slightly smaller, and differently, the peak value with FSI is larger with low flow rate. In addition, the effect of FSI on the angle of radial force is quite complex, especially under 0.5Q condition. Fluctuation of radial deflection of the rotor has obvious four periods, of which the extent is relatively small under design condition and is relatively large under off-design condition. Finally, fluctuations of equivalent stress with time are obvious under different conditions, and stress value is small. The proposed research establishes the FSI calculation method for centrifugal pump analysis, and ensures the existing affect by fluid structure interaction.
