Given that current axial flow blood pumps have certain structural defects,resulting in poor performance and inferior blood compatibility,an integrated axial flow blood pump is developed,and its geometry is optimized using computational fluid dynamics method.The study also investigates the effects of different operational parameters on the performance of the blood pump and compares with experimental data to determine the optimal conditions.Additionally,the flow patterns of the blood pump are comprehensively analyzed for further revealing the internal flow phenomena,and the behavior of red blood cells in the blood flow and their response to shear stress are simulated using discrete phase model to evaluate the blood compatibility of the blood pump.The study shows that the novel blood pump performed well in terms of head.Under the optimal condition with a rotational speed of 9 000 r/min and a flow rate of 6.24 L/min,the blood pump improves the head by 16%as compared with the original structure,and reaches 25%efficiency,which can meet the physiological needs of most people.The pressure gradient and velocity gradient in most areas within the blood pump are smooth,and the internal flow patterns are generally stable,effectively avoiding the occurrence of hemolysis.The optimized blood pump can ensure high-level performance and favorable flow field characteristics while maintaining superior blood compatibility,which provides important reference for the structural optimization of axial flow blood pumps.

Objective To provide a reference for the selection of frailty assessment tools for stroke patients by conducting a literature review of existing frailty assessment tools for stroke patients. Methods Systematic searches were conducted in PubMed, Web of Science, EMbase, SinoMed, Wanfang, VIP, and China National Knowledge Infrastructure(CNKI) databases from their inception to May 2023. The literature that met the research purpose and question were screened, and the basic information of each article, including the first author, publication year, country of publication, type of research design, name of the assessment tool, dimensions of scale, the number of items, and assessment time, was extracted. Results A total of 1, 729 articles were retrieved in this study. After multiple screenings, 22 articles (including 8 frailty assessment tools) were ultimately included. The analysis results showed that the evaluation indicators, evaluation time, and evaluation methods of the 8 frailty assessment tools were different and had their own advantages and disadvantages. Among them, the frailty index was the most commonly used frailty assessment tool for stroke patients. The selection of effective frailty assessment tools for stroke patients is essential for strengthening prestroke risk stratification and improving poststroke outcomes. Conclusion There are significant differences among different frailty assessment tools, and existing assessment tools have limitations in measuring frailty in stroke patients. Comprehensive assessments should be conducted in combination with clinicians' experience and judgment. New frailty assessment tools are needed in future research to better guide the rehabilitation treatment and management of stroke patients.

Radiotherapy is widely used in the management of advanced colorectal cancer (CRC). However, the clinical efficacy is limited by the safe irradiated dose. Sensitizing tumor cells to radiotherapy via interrupting DNA repair is a promising approach to conquering the limitation. The BRCA1-BARD1 complex has been demonstrated to play a critical role in homologous recombination (HR) DSB repair, and its functions may be affected by HERC2 or BAP1. Accumulated evidence illustrates that the ubiquitination-deubiquitination balance is involved in these processes; however, the precise mechanism for the cross-talk among these proteins in HR repair following radiation hasn't been defined. Through activity-based profiling, we identified PT33 as an active entity for HR repair suppression. Subsequently, we revealed that BAP1 serves as a novel molecular target of PT33 via a CRISPR-based deubiquitinase screen. Mechanistically, pharmacological covalent inhibition of BAP1 with PT33 recruits HERC2 to compete with BARD1 for BRCA1 interaction, interrupting HR repair. Consequently, PT33 treatment can substantially enhance the sensitivity of CRC cells to radiotherapy in vitro and in vivo. Overall, these findings provide a mechanistic basis for PT33-induced HR suppression and may guide an effective strategy to improve therapeutic gain.

[This corrects the article DOI: 10.1016/j.apsb.2021.09.004.].

Objective:To explore the application of PDCA (plan, do, check, act) cycle theory in the teaching of eight-year clinical medical students for the course of Laboratory Diagnostics.Methods:From September 2021 to November 2022, the students majoring in clinical medicine of eight-year system who were studying the course of Laboratory Diagnostics at Peking Union Medical College were selected as the research objects. The teaching reform of the course of Laboratory Diagnostics was carried out according to the four stages of PDCA cycle theory, and the teaching effect was evaluated by the final examination results and questionnaire survey scores of the students.Results:The score of theoretical examination of eight-year students in 2018 was (86.7±4.68) points, which was higher than that of students in 2017 [(83.3±3.89) points], and the difference was statistically significant ( P<0.05). The questionnaire survey results of the two groups of students showed that the rating of experimental course was higher than that of theoretical course ( P<0.05). After the teaching reform based on PDCA cycle theory, the questionnaire survey scores of theoretical course [(3.83±0.25) points vs (2.94±0.28) points] and experimental course [(4.13±0.09) points vs (3.32±0.12) points] in students of 2018 were higher than those of 2017 (all P<0.001). Conclusion:PDCA cycle theory provides new methods and ideas for teaching management, which helps to improve the performance of clinical medical students of eight-year system and their recognition of the course.

The spread of coronavirus disease 2019 (COVID-19) throughout the world has resulted in stressful healthcare burdens and global health crises. Developing an effective measure to protect people from infection is an urgent need. The blockage of interaction between angiotensin-converting enzyme 2 (ACE2) and S protein is considered an essential target for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) drugs. A full-length ACE2 protein could be a potential drug to block early entry of SARS-CoV-2 into host cells. In this study, a therapeutic strategy was developed by using extracellular vesicles (EVs) with decoy receptor ACE2 for neutralization of SARS-CoV-2. The EVs embedded with engineered ACE2 (EVs-ACE2) were prepared; the EVs-ACE2 were derived from an engineered cell line with stable ACE2 expression. The potential effect of the EVs-ACE2 on anti-SARS-CoV-2 was demonstrated by both in vitro and in vivo neutralization experiments using the pseudovirus with the S protein (S-pseudovirus). EVs-ACE2 can inhibit the infection of S-pseudovirus in various cells, and importantly, the mice treated with intranasal administration of EVs-ACE2 can suppress the entry of S-pseudovirus into the mucosal epithelium. Therefore, the intranasal EVs-ACE2 could be a preventive medicine to protect from SARS-CoV-2 infection. This EVs-based strategy offers a potential route to COVID-19 drug development.

Tryptophan 2,3-dioxygnease 2 (TDO2) is specific for metabolizing tryptophan to kynurenine (KYN), which plays a critical role in mediating immune escape of cancer. Although accumulating evidence demonstrates that TDO2 overexpression is implicated in the development and progression of multiple cancers, its tumor-promoting role in esophageal squamous cell carcinoma (ESCC) remains unclear. Here, we observed that TDO2 was overexpressed in ESCC tissues and correlated significantly with lymph node metastasis, advanced clinical stage, and unfavorable prognosis. Functional experiments showed that TDO2 promoted tumor cell proliferation, migration, and colony formation, which could be prevented by inhibition of TDO2 and aryl hydrocarbon receptor (AHR). Further experimentation demonstrated that TDO2 could promote the tumor growth of KYSE150 tumor-bearing model, tumor burden of C57BL/6 mice with ESCC induced by 4-NQO, enhance the expression of phosphorylated AKT, with subsequent phosphorylation of GSK3

Objective:To evaluate consistency between 2-fold serial and 4-fold serial diluted neutralization tests against Enterovirus A71 (EV-A71) in estimating titer, Geometric mean titer (GMT), seroprevalence, and seroincidence.Methods:Based on a prospective cohort of 1-9 years old children, mothers and infants established in Anhua County, Hunan Province, during 2013-2018, from which 92 participants with a total of 386 blood specimens were sampled and tested with a 2-fold serial dilution and a 4-fold serial dilution neutralization tests against EV-A71 at the same time. Agreement was estimated using the Bland-Altman method. Stratified analysis was conducted to estimate effect dilution approach on GMT, seroprevalence and seroincidence.Results:The mean difference (0.04, 95% CI:-0.02-0.10) between the two dilution approaches was not significant. However, the limits of agreement (LOA) (-1.12-1.21), with the 95% confidence interval of upper LOA (1.10-1.31) and of lower LOA (-1.22--1.02), significantly exceeded the Clinic accept interval (-1, 1) indicating insufficient agreement between the two approaches in practice. While the dilution approaches did not affect estimates of GMT of the total population and the positive population, and seroincidence with seroconversion only, the differences were 2, 6 and 2%, respectively ( P>0.05). Estimates of seroincidence with at least 4-fold increase and seroconversion/4-fold increase were significantly higher using a 4-fold dilution neutralization test compared to the 2-fold dilution neutralization test with 8% (95% CI: 1%-12%) and 9% (95% CI: 1%-17%), respectively. Conclusion:The 2-dilution and 4-dilution neutralization tests yielded comparable results when estimating the population′s GMT; however, the difference between the two is not negligible when assessing the seroincidence.

Objective:To evaluate consistency between 2-fold serial and 4-fold serial diluted neutralization tests against Enterovirus A71 (EV-A71) in estimating titer, Geometric mean titer (GMT), seroprevalence, and seroincidence.Methods:Based on a prospective cohort of 1-9 years old children, mothers and infants established in Anhua County, Hunan Province, during 2013-2018, from which 92 participants with a total of 386 blood specimens were sampled and tested with a 2-fold serial dilution and a 4-fold serial dilution neutralization tests against EV-A71 at the same time. Agreement was estimated using the Bland-Altman method. Stratified analysis was conducted to estimate effect dilution approach on GMT, seroprevalence and seroincidence.Results:The mean difference (0.04, 95% CI:-0.02-0.10) between the two dilution approaches was not significant. However, the limits of agreement (LOA) (-1.12-1.21), with the 95% confidence interval of upper LOA (1.10-1.31) and of lower LOA (-1.22--1.02), significantly exceeded the Clinic accept interval (-1, 1) indicating insufficient agreement between the two approaches in practice. While the dilution approaches did not affect estimates of GMT of the total population and the positive population, and seroincidence with seroconversion only, the differences were 2, 6 and 2%, respectively ( P>0.05). Estimates of seroincidence with at least 4-fold increase and seroconversion/4-fold increase were significantly higher using a 4-fold dilution neutralization test compared to the 2-fold dilution neutralization test with 8% (95% CI: 1%-12%) and 9% (95% CI: 1%-17%), respectively. Conclusion:The 2-dilution and 4-dilution neutralization tests yielded comparable results when estimating the population′s GMT; however, the difference between the two is not negligible when assessing the seroincidence.

Objective:To build a medical service experience system based on role play of hospital staff, and explore its contribution to upgrading medical service, elevating medical service quality, and improving patients′ satisfaction.Methods:An indicator system for medical service experience was developed via literature review. 20 newly recruited hospital employees in 2019 were sampled randomly to form a service experience team, who were arranged to experience the full medical service process of outpatients and inpatients based on role play. The questionnaire for service quality based on patient perception and expectation was used to survey the expectation and perception values of those role players on their medical service experiences, and summarize the defects found on such six dimensions as hospital reliability, responsiveness, tangibility, assurance, empathy and cost-effectiveness. After due corrections of these defects, further experiences and patient satisfaction survey were made to assess the effects of such actions taken. Paired t test was used respectively in statistical analysis of service experience value and actual perception value, as well as the perception values before and after the actions taken, and χ2 test was used for a statistical analysis of patient satisfaction. Results:Role players experienced respectively at the emergency, outpatient and inpatient departments of the hospital for a week in August 2019. Statistics of their experiences indicated≥0.50 points difference between the mean expectation and perception values on doctor-patient communication, patient help responsiveness, outpatient process, examination report delivery duration, service attitude, patient trust on medical workers, medical environment and patient privacy protection.Following a 3-month reform, role players found improvements in such aspects as hospital reliability, responsiveness, tangibility, assurance, empathy and cost-effectiveness; patient satisfaction improved sizably in December 2019 over January of the same year( P<0.05). Conclusions:The construction and application of the medical service experience system based on role play of hospital staff prove highly useful in upgrading medical service actions, improving medical service quality, and improving patient satisfaction.