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

BACKGROUND: Previous evidence showed that ambient air pollution and cardiovascular mortality are related. However, there is a lack of evidence towards the modification effect of long-term lifestyle on the association between short-term ambient air pollution and death from cardiovascular events. METHOD: A total of 14,609 death from major adverse cardiovascular events (MACE) were identified among the China Kadoorie Biobank participants from 2013 to 2018. Ambient air pollution exposure including particulate matter 2.5 (PM_2.5), SO₂, NO₂, CO, and O₃ from the same period were obtained from space-time model reconstructions based on remote sensing data. Case-crossover design and conditional logistic regression was applied to estimate the effect of short-term exposure to air pollutants on MACE mortality. RESULTS: We found MACE mortality was significantly associated with PM_2.5 (relative percent increase 2.91% per 10 µg/m³ increase, 95% CI 1.32-4.53), NO₂ (5.37% per 10 µg/m³ increase, 95% CI 1.56-9.33), SO₂ (6.82% per 10 µg/m³ increase, 95% CI 2.99-10.80), and CO (2.24% per 0.1 mg/m³ increase, 95% CI 1.02-3.48). Stratified analyses indicated that drinking was associated with elevated risk of MACE mortality with NO₂ and SO₂ exposure; physical inactivity was associated with higher risk of death from MACE when exposed to PM_2.5; and people who had balanced diet had lower risk of MACE mortality when exposed to CO and NO₂. CONCLUSIONS The study results showed that short-term exposure to ambient PM_2.5, NO₂, SO₂, and CO would aggravate the risk of cardiovascular mortality, yet healthy lifestyle conduct might mitigate such negative impact to some extent.
Humans ; Cardiovascular Diseases/epidemiology* ; China/epidemiology* ; Male ; Female ; Air Pollution/adverse effects* ; Middle Aged ; Air Pollutants/analysis* ; Particulate Matter/analysis* ; Environmental Exposure/adverse effects* ; Life Style ; Aged ; Adult ; Risk Factors ; Cross-Over Studies ; East Asian People

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Objective:To investigate whether escin(ESC)and dextromethorphan(DEX)have the protective effects on the progression and symptoms of Alzheimer disease(AD).Methods:The AD model of Caenorhabditis elegans(C.elegans)was established by transgenic amyloid β-protein(Aβ protein).Different concentrations of ESC or DEX or 50 μmol/L memantine(MEM)were used to treat the AD model worms,and their lifespan was detected.The movement ability of AD model C.elegans was evalua-ted by body bending frequency and head swinging frequency.The changes in cognitive functions of AD model C.elegans before and after treatment were detected by chemotaxis experiments.The changes in A βprotein and reactive oxygen species(ROS)content in C.elegans were detected.The changes in gene pathways related to oxidative stress were detected by Real-time quantitative polymerase chain reaction(RT-qPCR).Results:At high dose 1 000 μmol/L,ESC or DEX treatment showed no significant effects on the activity of C.elegans.Compared with untreated worms,the survival time of AD model C.elegans in the 20 μmol/L ESC and 60 μmol/L DEX intervention groups was significantly extended.In the middle stage of AD progression,the body bending frequency and head swinging frequency of AD model worms after ESC or DEX treatment was significantly increased compared with the untreated control group with DEX being more effective in the recovery of head swinging frequency.For the early cognitive function tests,the chemotaxis index of ESC or DEX treated worms was significantly higher than that of the untreated worms,which correlated with marked reductions in the Aβ protein levels.The reactive oxygen species content in the drug intervention group was also lower than that in the control group.RT-qPCR results showed that ESC could inhibit oxidative stress in the AD model C.elegans by a 2-fold upregulation of skn1 expression.Conclusion:ESC and DEX could improve the reductions of movement ability and cognitive function in the AD model worms and delay the aggravation of AD-related symptoms.ESC delays the progression of AD pos-sibly by activating the SKN-1/Nrf2 pathway to protect against oxidative injury in the AD model.

BACKGROUND: Prospective evidence on how offspring number influences morbidity and mortality remains limited. This study investigated the associations between number of offspring and morbidity and mortality risks among 0.5 million Chinese adults. METHODS: By using data from the China Kadoorie Biobank (CKB; n = 512,723, an approximately 12-year follow-up), sex-stratified phenome-wide association study (PheWAS) analyses were conducted to investigate associations between offspring number (without vs . with offspring; more than one vs . one offspring) and risks of ICD10-coded morbidity and mortality. Sex-specific adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) were estimated by Cox proportional-hazards models. RESULTS: Among 210,129 men and 302,284 women aged 30-79 years, 1,338,837 incident events were recorded. PheWAS results revealed that offspring number was associated with disease risks across multiple systems. Cox models showed that childless men ( vs . one offspring) had higher risks for nine of 36 diseases, while childless women for five of 37. Each additional offspring was associated with reduced risks of mental and behavioral disorders in men (aHR [95% CI] = 0.93 [0.87-0.98]) and both mental and behavioral disorders (aHR [95% CI] = 0.93 [0.89-0.97]) and breast cancer (aHR [95% CI] = 0.82 [0.78-0.86]) in women. However, each additional offspring was associated with a 4% increase in the risk of cholelithiasis and cholecystitis in women (aHR [95% CI] = 1.04 [1.02-1.07]). Among 282,630 patients, 44,533 deaths were documented. Childless patients had higher mortality risk in both men (aHR [95% CI] = 1.37 [1.28-1.47]) and women (aHR [95% CI] = 1.27 [1.15-1.41]). For men, each additional offspring reduced mortality by 4% (aHR [95% CI] = 0.96 [0.95-0.98]), while for women, the lowest risk was observed among those with three to four offspring ( Pnonlinear <0.0001). CONCLUSIONS Offspring number is closely linked to morbidity and mortality risks. Further research is warranted to verify our findings and clarify the underlying mechanisms involved.
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; China/epidemiology* ; Morbidity ; Proportional Hazards Models ; Prospective Studies ; Risk Factors ; Family Characteristics ; Mortality ; East Asian People

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 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 whether escin(ESC)and dextromethorphan(DEX)have the protective effects on the progression and symptoms of Alzheimer disease(AD).Methods:The AD model of Caenorhabditis elegans(C.elegans)was established by transgenic amyloid β-protein(Aβ protein).Different concentrations of ESC or DEX or 50 μmol/L memantine(MEM)were used to treat the AD model worms,and their lifespan was detected.The movement ability of AD model C.elegans was evalua-ted by body bending frequency and head swinging frequency.The changes in cognitive functions of AD model C.elegans before and after treatment were detected by chemotaxis experiments.The changes in A βprotein and reactive oxygen species(ROS)content in C.elegans were detected.The changes in gene pathways related to oxidative stress were detected by Real-time quantitative polymerase chain reaction(RT-qPCR).Results:At high dose 1 000 μmol/L,ESC or DEX treatment showed no significant effects on the activity of C.elegans.Compared with untreated worms,the survival time of AD model C.elegans in the 20 μmol/L ESC and 60 μmol/L DEX intervention groups was significantly extended.In the middle stage of AD progression,the body bending frequency and head swinging frequency of AD model worms after ESC or DEX treatment was significantly increased compared with the untreated control group with DEX being more effective in the recovery of head swinging frequency.For the early cognitive function tests,the chemotaxis index of ESC or DEX treated worms was significantly higher than that of the untreated worms,which correlated with marked reductions in the Aβ protein levels.The reactive oxygen species content in the drug intervention group was also lower than that in the control group.RT-qPCR results showed that ESC could inhibit oxidative stress in the AD model C.elegans by a 2-fold upregulation of skn1 expression.Conclusion:ESC and DEX could improve the reductions of movement ability and cognitive function in the AD model worms and delay the aggravation of AD-related symptoms.ESC delays the progression of AD pos-sibly by activating the SKN-1/Nrf2 pathway to protect against oxidative injury in the AD model.

To formulate an expert consensus on the principles of preoperative hair removal and provide scientific guidance for standardized removal of hair before surgical procedures so as to reduce the incidence of surgical site infections.METHODS Led by the Hospital Management Institute of National Health Commission of the People's Republic of China,this consensus was reached with the joint efforts from the expects of relevant fields such as surgeries,interventional therapies,nursing,and infection prevention and control.The consensus facilitates the classification and evaluation of literatures by following the evidence grade formulated by Oxford Evidence-based Medicine Center and focuses on the association of preoperative hair removal with surgical site infection,it reaches the evidence grade of expert consensus and recommendation intensity by integrating with discussions on meetings and clinical experience of the expects from relevant fields.RESULTS A total of 6 items of consensus were reached by summarizing the latest evidence on the aspects including the indications for preoperative hair removal,tools,range,timing and places.CONCLUSION The consensus,to some extent,make supplements to and complete the exiting regulations and standards.It provides guidance for the medical institutions to carry out the preoperative hair removal.

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.