Tesla blood pumps demonstrate a reduced propensity for hemolysis and thrombosis compared with vane blood pumps. Considering the restricted driving force within the secondary flow channel of vane blood pumps, along with the low hydraulic efficiency of conventional Tesla blood pumps and their internal flow characteristics that significantly contribute to hemolysis and thrombosis, this study introduces a set of vanes atop the rotor of the Tesla blood pump. This forms a dual-fluid domain rotor, and an axial dual-outlet volute shell structure is adopted to realize the separation of the fluid domains. Through numerical simulations of the new structure, a comparative analysis was conducted in this study on the internal flow characteristics of double-outlet and single-outlet volute shells, and symmetric and asymmetric cross-sections of the same rotor. The results indicate that the flow field distribution is more uniform under the double-outlet volute shell structure, and overall energy dissipation is decreased. After implementing the double-outlet design, in the asymmetric cross-section, compared with the symmetric cross-section, the fluid velocity gradient and turbulent kinetic energy at the tongue of the septum are reduced, and the fluid velocity gradient at the convergence of the diffuser tube outlets are also decreased. The maximum scalar stress is lower, and the decline in head and efficiency is mitigated. Moreover, compared with the single-outlet volute shell, the hemolysis index in the asymmetric cross-section is reduced. In summary, this paper proposes a novel dual-outlet centrifugal disk blood pumps, which can provide a reference for the structural design and performance optimization of magnetically levitated centrifugal blood pumps.
Heart-Assist Devices ; Humans ; Equipment Design ; Hemolysis ; Computer Simulation

[This corrects the article DOI: 10.1016/j.apsb.2024.03.030.].

Objective To study the effects of different clearance conditions(equal upper and lower axial clearance,change of upper/lower axial clearance,axial displacement of blades)on efficiency and hemolysis performance of blood pump.Methods The blood pumps under three kinds of clearance conditions were numerically simulated by computational fluid dynamics.Results For efficiency,when the upper and lower axial clearance was equal,the lower axial clearance was unchanged and the upper axial clearance was reduced,the efficiency of blood pump could be improved by 0.85%,1.71%and 2.90%,respectively.While the upper shaft clearance remained unchanged,the lower shaft clearance was decreased by 1.18%.For hemolysis,the increase of the clearance could reduce the hemolysis index(HI)under the first two clearance conditions,while the axial migration of the blade wheel would increase the HI.When the upper axial clearance was unchanged and the lower axial clearance was 0.3 mm,the HI was the largest,which was 8.65×10-4.When the upper and lower axial clearance was 0.7 mm,the HI was the smallest,which was 4.51×10-4.Conclusions Improving blood pump clearance is helpful to optimize the performance of blood pump.This study can provide some references for the design and optimization of interstitial structure of blood pump.

Objective To investigate the impact of variations in volute cross-sectional area on the flow characteristics and hemolytic performance of centrifugal blood pumps by designing six volute structures.Methods Computational fluid dynamics and the Lagrangian method were used to analyze flow characteristics and predict hemolysis in blood pumps with different volute designs.Results The annular volute pump showed the poorest hydraulic performance,while the hydraulic performance of the S-shaped volute was the best,which was improved by 35.29％compared to that of the annular volute.Some volutes experienced stagnation zones at the helical inlet(0°-90°)and significant backflow at the outlet(270°-360°).The downward concave-shaped volute had the highest hemolysis index(HI),i.e.,9.59×10-4.Meanwhile,the HI of the annular volute was the lowest,which was 71.85％less than the concave-shaped volute.Conclusions Reducing the gradient of the area variation at the helical inlet and outlet can prevent flow stagnation and backflow.A higher HI arises due to the prolonged exposure of red blood cells to high shear stress.This study provides a theoretical basis for designing and optimizing volute structures of centrifugal blood pumps.

Objective:To investigate the clinical characteristics and independent risk factors of severe disease in patients with anti-nuclear matrix protein (NXP) 2 antibody-positive juvenile dermatomyositis (JDM).Methods:A retrospective cohort study was conducted, including 219 anti-NXP2 antibody-positive JDM patients admitted to 23 children′s hospitals across China from July 2011 to July 2023. Patients were classified into severe and non-severe groups based on classification criteria for severe dermatomyositis. Demographic characteristics, clinical manifestations, and laboratory parameters were compared between the 2 groups using independent sample t-test, Mann-Whitney U test, or χ2 test. Univariate and multivariate Logistic regression analyses were performed to identify risk factors for severe disease. The receiver operating characteristic curve was employed to calculate optimal cut-off values. Results:Among the 219 patients, 108 were male and 111 were female, with an age at onset of 6.3 (3.5, 9.4) years. The severe group comprised 69 patients, and the non-severe group 150 patients. The severe group had significantly higher rates of fever, heliotrope rash, subcutaneous edema, periorbital edema, anti-Ro52 antibody positivity, as well as elevated levels of ferritin-to-albumin ratio (FAR), creatine kinase (CK), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) (all P<0.05). Multivariate analysis identified anti-Ro52 antibody positivity ( OR=13.26, 95% CI 1.37-128.29) and elevated FAR ( OR=1.90, 95% CI 1.09-2.31) as independent risk factors for severe anti-NXP2 antibody-positive JDM (both P<0.05). Receiver operating characteristic curve analysis revealed that a FAR cutoff value of 6.82 predicted severe disease with an area under the curve of 0.87 (95% CI 0.81-0.94, P<0.001), sensitivity of 0.85, and specificity of 0.70. All patients received glucocorticoid therapy, and the severe group received higher proportions of steroid pulse therapy, cyclophosphamide, mycophenolate mofetil, intravenous immunoglobulin, biologics, and adjuvant treatments compared to the non-severe group (all P<0.05). In terms of outcomes, 2 patients (2.9%) in the severe group died (due to neurological involvement and intestinal perforation, respectively), while the remaining patients achieved complete clinical response or remission. All patients in the non-severe group achieved remission. Conclusions:The primary clinical features of anti-NXP2 antibody-positive JDM included fever, heliotrope rash, subcutaneous edema, periorbital edema, anti-Ro52 antibody positivity, and elevated levels of CK, AST, LDH, and FAR. Furthermore, anti-Ro52 antibody positivity and a FAR>6.82 were identified as independent risk factors.

AIM:To investigate the antiviral effica-cy and mechanism of Qingre Xiaoyanning(QRXYN)in vivo,and provide experimental basis for their prevention and treatment of influenza A virus.METHODS:We constructed a mouse model infect-ed with influenza A H3N2 virus.To evaluate the therapeutic effect of QRXYN on influenza A virus,we measured the body weight changes,pathologi-cal changes in lung tissue,hemagglutination titer,and viral load in mouse.To evaluate the possible mechanism of QRXYN's anti influenza A virus infec-tion,we used the ELISA to measure the levels of TNF-α,IL-1β,IL-4,IFN-γ,and vascular cell adhesion molecule-1(VCAM-1)in mouse bronchoalveolar Ia-vage fluid;used flow cytometry to assess the pro-portions of macrophages(F4/80),helper T lympho-cytes(CD4+T lymphocytes),and natural killer(NK)cells in lung tissue;and used Western blotting to detect the expression of Toll-like receptor 4(TLR4),myeloid differentiation factor 88(MYD88),inhibitor of kappa B kinase-β(IKK-β),NF-kappa-B inhibitor al-pha(IκBα),and phospho-IKB alpha(p-IκBα)in lung tissue.RESULTS:Compared to the model group,both Oseltamivir and QRXYN can alleviate the se-verity of lung tissue lesions in mice,decrease the blood coagulation titer and viral load of mouse lung tissue(P＜0.01),lower the levels of TNF-α,IL-4,and VCAM-1 in bronchoalveolar lavage fluid(P＜0.05,P＜0.01),reduce the proportion of macro-phages(P＜0.05,P＜0.01),and increase the propor-tion of CD4+T lymphocytes and NK cells(P＜0.05,P＜0.01).Additionally,oseltamivir can reduce the ex-pression of MYD88 protein in mouse lungs(P＜0.05),while QRXYN can decrease the expression of IKK-β and P-IκBα proteins in mouse lungs(P＜0.05).CONCLUSION:QRXYN have good in vivo antiviral ef-fects against the influenza A virus,and their mecha-nism may be related to the regulation of the immu-nologic function and NF-κB signal pathway.

AIM:To investigate the antiviral effica-cy and mechanism of Qingre Xiaoyanning(QRXYN)in vivo,and provide experimental basis for their prevention and treatment of influenza A virus.METHODS:We constructed a mouse model infect-ed with influenza A H3N2 virus.To evaluate the therapeutic effect of QRXYN on influenza A virus,we measured the body weight changes,pathologi-cal changes in lung tissue,hemagglutination titer,and viral load in mouse.To evaluate the possible mechanism of QRXYN's anti influenza A virus infec-tion,we used the ELISA to measure the levels of TNF-α,IL-1β,IL-4,IFN-γ,and vascular cell adhesion molecule-1(VCAM-1)in mouse bronchoalveolar Ia-vage fluid;used flow cytometry to assess the pro-portions of macrophages(F4/80),helper T lympho-cytes(CD4+T lymphocytes),and natural killer(NK)cells in lung tissue;and used Western blotting to detect the expression of Toll-like receptor 4(TLR4),myeloid differentiation factor 88(MYD88),inhibitor of kappa B kinase-β(IKK-β),NF-kappa-B inhibitor al-pha(IκBα),and phospho-IKB alpha(p-IκBα)in lung tissue.RESULTS:Compared to the model group,both Oseltamivir and QRXYN can alleviate the se-verity of lung tissue lesions in mice,decrease the blood coagulation titer and viral load of mouse lung tissue(P＜0.01),lower the levels of TNF-α,IL-4,and VCAM-1 in bronchoalveolar lavage fluid(P＜0.05,P＜0.01),reduce the proportion of macro-phages(P＜0.05,P＜0.01),and increase the propor-tion of CD4+T lymphocytes and NK cells(P＜0.05,P＜0.01).Additionally,oseltamivir can reduce the ex-pression of MYD88 protein in mouse lungs(P＜0.05),while QRXYN can decrease the expression of IKK-β and P-IκBα proteins in mouse lungs(P＜0.05).CONCLUSION:QRXYN have good in vivo antiviral ef-fects against the influenza A virus,and their mecha-nism may be related to the regulation of the immu-nologic function and NF-κB signal pathway.

Objective To investigate the impact of variations in volute cross-sectional area on the flow characteristics and hemolytic performance of centrifugal blood pumps by designing six volute structures.Methods Computational fluid dynamics and the Lagrangian method were used to analyze flow characteristics and predict hemolysis in blood pumps with different volute designs.Results The annular volute pump showed the poorest hydraulic performance,while the hydraulic performance of the S-shaped volute was the best,which was improved by 35.29％compared to that of the annular volute.Some volutes experienced stagnation zones at the helical inlet(0°-90°)and significant backflow at the outlet(270°-360°).The downward concave-shaped volute had the highest hemolysis index(HI),i.e.,9.59×10-4.Meanwhile,the HI of the annular volute was the lowest,which was 71.85％less than the concave-shaped volute.Conclusions Reducing the gradient of the area variation at the helical inlet and outlet can prevent flow stagnation and backflow.A higher HI arises due to the prolonged exposure of red blood cells to high shear stress.This study provides a theoretical basis for designing and optimizing volute structures of centrifugal blood pumps.

Objective To study the effects of different clearance conditions(equal upper and lower axial clearance,change of upper/lower axial clearance,axial displacement of blades)on efficiency and hemolysis performance of blood pump.Methods The blood pumps under three kinds of clearance conditions were numerically simulated by computational fluid dynamics.Results For efficiency,when the upper and lower axial clearance was equal,the lower axial clearance was unchanged and the upper axial clearance was reduced,the efficiency of blood pump could be improved by 0.85%,1.71%and 2.90%,respectively.While the upper shaft clearance remained unchanged,the lower shaft clearance was decreased by 1.18%.For hemolysis,the increase of the clearance could reduce the hemolysis index(HI)under the first two clearance conditions,while the axial migration of the blade wheel would increase the HI.When the upper axial clearance was unchanged and the lower axial clearance was 0.3 mm,the HI was the largest,which was 8.65×10-4.When the upper and lower axial clearance was 0.7 mm,the HI was the smallest,which was 4.51×10-4.Conclusions Improving blood pump clearance is helpful to optimize the performance of blood pump.This study can provide some references for the design and optimization of interstitial structure of blood pump.

Objective:To investigate the clinical characteristics and independent risk factors of severe disease in patients with anti-nuclear matrix protein (NXP) 2 antibody-positive juvenile dermatomyositis (JDM).Methods:A retrospective cohort study was conducted, including 219 anti-NXP2 antibody-positive JDM patients admitted to 23 children′s hospitals across China from July 2011 to July 2023. Patients were classified into severe and non-severe groups based on classification criteria for severe dermatomyositis. Demographic characteristics, clinical manifestations, and laboratory parameters were compared between the 2 groups using independent sample t-test, Mann-Whitney U test, or χ2 test. Univariate and multivariate Logistic regression analyses were performed to identify risk factors for severe disease. The receiver operating characteristic curve was employed to calculate optimal cut-off values. Results:Among the 219 patients, 108 were male and 111 were female, with an age at onset of 6.3 (3.5, 9.4) years. The severe group comprised 69 patients, and the non-severe group 150 patients. The severe group had significantly higher rates of fever, heliotrope rash, subcutaneous edema, periorbital edema, anti-Ro52 antibody positivity, as well as elevated levels of ferritin-to-albumin ratio (FAR), creatine kinase (CK), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) (all P<0.05). Multivariate analysis identified anti-Ro52 antibody positivity ( OR=13.26, 95% CI 1.37-128.29) and elevated FAR ( OR=1.90, 95% CI 1.09-2.31) as independent risk factors for severe anti-NXP2 antibody-positive JDM (both P<0.05). Receiver operating characteristic curve analysis revealed that a FAR cutoff value of 6.82 predicted severe disease with an area under the curve of 0.87 (95% CI 0.81-0.94, P<0.001), sensitivity of 0.85, and specificity of 0.70. All patients received glucocorticoid therapy, and the severe group received higher proportions of steroid pulse therapy, cyclophosphamide, mycophenolate mofetil, intravenous immunoglobulin, biologics, and adjuvant treatments compared to the non-severe group (all P<0.05). In terms of outcomes, 2 patients (2.9%) in the severe group died (due to neurological involvement and intestinal perforation, respectively), while the remaining patients achieved complete clinical response or remission. All patients in the non-severe group achieved remission. Conclusions:The primary clinical features of anti-NXP2 antibody-positive JDM included fever, heliotrope rash, subcutaneous edema, periorbital edema, anti-Ro52 antibody positivity, and elevated levels of CK, AST, LDH, and FAR. Furthermore, anti-Ro52 antibody positivity and a FAR>6.82 were identified as independent risk factors.