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Background: The outcomes of transcatheter aortic valve replacement (TAVR) employing the second-generation retrievable VenusA-Pro and VenusA-Plus delivery systems with the self-expanding VenusA-Valve have not been described yet. This study aims to report the outcomes of these two second-generation delivery systems., Methods: From January 2022 to April 2023, we prospectively enrolled patients with severe aortic stenosis undergoing TAVR with VenusA-Pro from three centers across China in this first-in-man study and retrospectively identified those undergoing TAVR with VenusA-Plus. All outcomes were reported according to the Valve Academic Research Consortium 3 definition. The primary outcome was 30-day all-cause mortality., Results: A total of 156 patients were included, of which 46 underwent TAVR with VenusA-Pro and 110 underwent TAVR with VenusA-Plus. The Society of Thoracic Surgeons median score was 2.1%, bicuspid anatomy prevalence rate was 55.1%, and the mean aortic root calcification volume was 693 mm 3 . The technical success rate was 91.7%, comparable between the VenusA-Pro and VenusA-Plus groups (87.0% vs. 93.6%, P  = 0.169). The 30-day all-cause mortality was 2.6%, similar between the VenusA-Pro and VenusA-Plus groups (2.2% vs. 2.7%, P  = 0.842). No myocardial infarction occurred. The incidences of stroke (0.6%), major bleeding (3.8%), major vascular complications (5.1%), acute kidney injury (9.0%), permanent pacemaker implantation (5.1%), new-onset atrial fibrillation (5.8%), and moderate-to-severe paravalvular aortic regurgitation (6.0%) were favorable and comparable between the two groups. The clinical outcomes were similar between the patients with bicuspid and tricuspid aortic valve, except that the incidence of permanent pacemaker implantation was lower in patients with bicuspid anatomy (1.2% vs. 10.6%, P  = 0.010)., Conclusions: The 30-day outcomes of TAVR with VenusA-Pro and VenusA-Plus were favorable and comparable., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Li, Sun, Luo, Zheng, Chen, Fu, Fang, Wang, Li, Fan and Luo.)

Backgrounds: The goal of this study was to assess the impact of neutrophil count, in patients with acute type A aortic dissection (ATAAD)., Methods: This study retrospectively collected data from patients between September 2017 and June 2021. Youden's index was used to determine the optimal cut-off value for the neutrophil count and patients were divided into two subgroups. A restricted cubic spline (RCS) was used to model the relationship between variables and in-hospital mortality. The least absolute shrinkage and selection operator (LASSO) method and multivariate logistic regression analyses were used to investigate the independent prognostic factors for in-hospital mortality in patients with ATAAD., Results: A total of 467 patients were enrolled in this study. In-hospital mortality was 7.28%. The group with elevated neutrophil counts had significantly higher mortality than the group with decreased neutrophil counts (10.8% vs. 3.2%, P  = 0.02). This data shows that elevated neutrophil count was significantly associated with in-hospital mortality (OR 3.07, 95% CI 1.22-7.62, P  = 0.02)., Conclusions: Neutrophil count is an independent risk factor for in-hospital mortality in patients with ATAAD. It is an effective inflammatory index, which can be individualized for patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Feng, Li, Wang, Li, Wu, Yang and Fan.)

Objectives: Isolated abdominal aortic dissection (IAAD) is extremely rare, with its optimal treatment and intervention timing remaining poorly understood. We aimed to study the natural history of IAAD and facilitate better clinical decision., Methods: Consecutive patients admitted to our institution from January 2016 to April 2021 were enrolled and followed up prospectively. All-cause death was taken as the primary endpoint., Results: A total of 68 patients with IAAD were included. The mean age at presentation was 61.2 ± 14.8 (Range: 26.0, 93.0) years and 55 (80.9%) were male. A total of 38 (55.9%) patients were treated conservatively, 27 (39.7%) received endovascular aneurysm repair (EVAR), and 3 (4.4%) underwent open surgery. After a mean follow-up of 2.4 years (Range: 0.1, 5.5), 9 (13.2%) patients died, 8 of whom (21.0%) were treated conservatively and 1 EVAR (3.7%). Compared with EVAR/open surgery, patient treated conservatively had a much worse survival ( p  = 0.043). There was no significant difference between different IAAD aortic sizes regarding mortality ( p  = 0.220). Patients with completely thrombosed false lumen fared improved survival rate, followed by partial thrombosis and patency, respectively, although not significantly ( p  = 0.190). No significant difference was observed between male and female concerning survival rate ( p  = 0.970). Patients without symptoms had a significantly improved survival ( p  = 0.048)., Conclusion: On the basis of patients' preference and surgeons' experience, a more aggressive treatment regimen for IAAD should be considered, with EVAR being the first choice, especially for those with persistent symptoms and patent false lumen, regardless of sex, age, or aortic size., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wu, Wu, Li, Zhuang, Cheng, Chen, Yang, Liu, Li, Fan and Sun.)

Objectives: We evaluated the feasibility, effectiveness, and safety of valve-sparing aortic root reconstruction with a bovine pericardium patch for patients with acute type A aortic dissection (ATAAD)., Methods: From January 2016 to January 2021, 895 consecutive patients with ATAAD received surgical treatment at our hospital. After applying our exclusion criteria, 508 patients were included in this research. Based on the attending surgeon's judgment and preference, 192 patients underwent our novel surgical novel surgical technique of valve-sparing aortic root reconstruction (repair group [RG]) and 316 patients underwent the Bentall procedure (Bentall group [BG])., Results: In the RG, the early mortality rate was 4.2% (8/192). In the BG, the early mortality rate was 5.1% (16/316). There were no significant differences between groups. The incidence of postoperative renal failure in the BG was significantly higher than that in the RG. The mean follow-up time was 2.93 years (standard deviation, ±1.38 years). There were no significant differences between groups regarding ATAAD-related mortality and reoperation. In the RG, the rate of freedom from aortic root reoperation at 5 years was 98.2%, and the grade of aortic regurgitation 6 months later was significant less than that before surgery, and it did not worsen during later follow-up., Conclusions: Valve-sparing aortic root reconstruction with a bovine pericardium patch can be successfully performed for selected patients with ATAAD and is associated with low in-hospital and late mortality rates and low root reoperation rates during early and midterm follow-up., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The handling editor ES declared a past co-authorship with the author RF., (Copyright © 2022 Yang, Li, Wu, Wu, Chen, Sun, Fan and Yu.)

Objective: The aim of the study was to investigate surgical modalities and outcomes in patients with type A aortic dissection involving arch anomalies., Method: Patients with type A aortic dissection who underwent surgical treatment at our center between January 2017 and 31 December 2020 were selected for this retrospective analysis. Data including computed tomography (CT), surgical records, and cardiopulmonary bypass records were analyzed. Perioperatively survived patients were followed up, and long-term mortality and aortic re-interventions were recorded., Result: A total of 81 patients with arch anomalies were included, 35 with "bovine" anomalies, 23 with an aberrant right subclavian artery, 22 with an isolated left vertebral artery, and one with a right-sided arch + aberrant left subclavian artery. The strategies of arch management and cannulation differed according to the anatomic variation of the aortic arch. In total, seven patients (9%) died after surgery. Patients with "bovine" anomalies had a higher perioperative mortality rate (14%) and incidence of neurological complications (16%). Overall, four patients died during the follow-up period, with a 6-year survival rate of 94.6% (70/74). A total of four patients underwent aortic re-intervention during the follow-up period; before the re-intervention, three received the en bloc technique (13.6% 3/22) and one received hybrid therapy (11.1% 1/9)., Conclusion: With complete preservation and reconstruction of the supra-arch vessels, patients with type A aortic dissection combining arch anomalies can achieve a favorable perioperative prognostic outcome. Patients who received the en bloc technique are more likely to require aortic re-intervention than patients who underwent total arch replacement with a four-branched graft vessel. Cannulation strategies should be tailored according to the variation of anatomy, but routine cannulation with the right axillary artery can still be performed in most patients with arch anomalies, even for patients with an aberrant right subclavian artery., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhu, Tong, Zhuang, Yang, Liang, Liu, Yu, Zhang, Chen, Liu, Yang, Li, Fan, Sun and Wu.)

Background: The management of malperfusion is vital to improve the outcomes of surgery for acute type A acute aortic dissection (ATAAD). Open arch repair under hypothermic circulatory arrest with selective antegrade cerebral perfusion (HCA/sACP) is safe and efficient but associated with inevitable hypothermia and ischemia-reperfusion injury. The aortic balloon occlusion (ABO) technique is shown to be organ protective by allowing higher temperature and shorter circulatory arrest time. In this study, we aimed to evaluate the safety and efficacy of this new technique for ATAAD patients with lower body malperfusion., Methods: Between January 2013 and November 2020, 355 ATAAD patients with lower body malperfusion who underwent arch repair in our institute were enrolled. The patients were divided into 2 groups: ABO group ( n = 85) and HCA/sACP group ( n = 271). Propensity score matching was performed to correct baseline differences., Results: Using the propensity score matching, 85 pairs were generated. Circulatory arrest time was significantly lower in the ABO group compared with the HCA/sACP group (median, 8 vs. 22 min; p < 0.001). The incidence of in-hospital mortality (10.6 vs. 12.9%; p = 0.812), stroke (7.1 vs. 7.1%; p = 1.000), dialysis (25.9 vs. 32.9%; p = 0.183), hepatic dysfunction (52.9 vs. 57.6%; p = 0.537), tracheostomy (4.7 vs. 2.4%; p = 0.682), paraplegia (1.2 vs. 4.7%; p = 0.368) were comparable between ABO and HCA/sACP groups. Other outcomes and major adverse events were comparable. The multivariable logistic analysis did not recognize ABO technique protective against any major adverse outcomes., Conclusions: For ATAAD patients with lower body malperfusion, the ABO technique allows the performance of arch repair with frozen elephant trunk (FET) under higher temperature and shorter circulatory arrest time. However, ABO technique did not improve perioperative outcomes. Future studies are warranted to evaluate the efficacy of this technique., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Tong, Sun, Wu, Zhao, Chen, Zhuang, Liu, Yang, Liang, Fan and Sun.)

Background: Acute type A aortic dissection (ATAAD) is a rare, life-threatening condition affecting the aorta. This study explores the relationship between the level of admission D-dimer, which was assessed during the first 2 h from admission, and in-hospital major adverse events (MAE) with ATAAD., Methods: A total of 470 patients with enhanced computed tomography (CT) confirmed diagnosis of ATAAD who underwent operation treatment in Guangdong Provincial People's hospital between September 2017 and June 2021 were enrolled in the present study. The X-tile program was used to determine the optimal D-dimer thresholds for risk. Restricted cubic spline (RSC) was performed to assess the association between D-dimer and endpoint. The perioperative data were compared between the two groups, univariate and multivariate analyses were used to investigate the risk factors of major adverse events (in-hospital mortality, gastrointestinal bleeding, paraplegia, acute kidney failure, reopen the chest, low cardiac output syndrome, cerebrovascular accident, respiratory insufficiency, MODS, gastrointestinal bleeding, and severe infection)., Results: Among 470 patients, 151 (32.1%) had MAE. In-hospital mortality was 7.44%. The patients with D-dimer >14,500 ng/ml were more likely to present with acute kidney failure, low cardiac output, cerebrovascular accident, multiple organ dysfunction syndromes (MODS), gastrointestinal bleeding, and severe infection. D-dimer level was an independent risk factor for acute kidney failure (OR 2.09, 95% CI: 1.25-3.51, p = 0.005), MODS (OR 6.40, 95% CI: 1.23-33.39, p = 0.028), gastrointestinal bleeding (OR 17.76, 95% CI: 1.99-158.78, p = 0.010) and mortality (OR 3.17, 95% CI: 1.32-7.63, p = 0.010). Multivariate regression analysis of adverse events also suggested that D-dimer >14,500 ng/ml (OR 1.68, 95% CI: 1.09-2.61, p = 0.020) was the independent risk factor of major adverse events., Conclusions: Increasing D-dimer levels were independently associated with the in-hospital MAE and thus can be used as a useful prognostic biomarker before the surgery., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Feng, Wang, Li, Wu, Kuang, Yang and Fan.)

Objective: This meta-analysis and systematic review investigated whether partial thrombosed false lumen was a predictor for adverse events in uncomplicated Type B aortic dissection (TBAD)., Methods: We performed the current systematic review of the medical literature according to the 2009 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The Newcastle-Ottawa Scale was used to evaluate the quality of individual studies. Search terms based on the MEDLINE database included "type B aortic dissection," "false lumen" and "thrombosis." The primary outcomes included mortality, intervention, and aortic growth., Results: Six studies were included in this systematic review, with a total number of 692 patients, including 197 patency (28.5%), 214 partial thrombosis (30.9%), and 281 complete thrombosis (40.6%). Due to the insufficient data for quantitative analysis, we only conducted a scoping review for mortality and intervention. For aortic growth, we conducted a meta-analysis based on Standardized Mean Difference (SMD). The SMD of PT vs. P by random effect model was -0.05 (random effect model) [95% confidence interval (CI), -0.39 to 0.29]. The 95% CI crossed with the null line of 0, indicating no significant difference. The SMD was 0.37 (fixed effects model) (95% CI, 0.03-0.71) and 0.70 (fixed effects model) (95% CI, 0.37-1.04) for PT vs. CT, and P vs. CT, respectively., Conclusions: Current researches on partial thrombosis of TBAD are inconsistent. Partial thrombosis is not associated with a faster aortic growth rate. Until more solid evidence is available, we do not recommend partial thrombosis as a surgical indication or high-risk profile for TBAD. Systematic Review Registration: Unique Identifier: CRD42019121912., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wu, Song, Li, Yang, Yu, Zhou, Sun and Fan.)

Background: Acute renal failure (ARF) is the most common major complication following cardiac surgery for acute aortic syndrome (AAS) and worsens the postoperative prognosis. Our aim was to establish a machine learning prediction model for ARF occurrence in AAS patients., Methods: We included AAS patient data from nine medical centers ( n = 1,637) and analyzed the incidence of ARF and the risk factors for postoperative ARF. We used data from six medical centers to compare the performance of four machine learning models and performed internal validation to identify AAS patients who developed postoperative ARF. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was used to compare the performance of the predictive models. We compared the performance of the optimal machine learning prediction model with that of traditional prediction models. Data from three medical centers were used for external validation., Results: The eXtreme Gradient Boosting (XGBoost) algorithm performed best in the internal validation process (AUC = 0.82), which was better than both the logistic regression (LR) prediction model (AUC = 0.77, p < 0.001) and the traditional scoring systems. Upon external validation, the XGBoost prediction model (AUC =0.81) also performed better than both the LR prediction model (AUC = 0.75, p = 0.03) and the traditional scoring systems. We created an online application based on the XGBoost prediction model., Conclusions: We have developed a machine learning model that has better predictive performance than traditional LR prediction models as well as other existing risk scoring systems for postoperative ARF. This model can be utilized to provide early warnings when high-risk patients are found, enabling clinicians to take prompt measures., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Li, Gong, Joshi, Sun, Huang, Fan, Gu, Zhang, Zou, Zhang, Qian, Qiao, Chen, Jiang and Zhang.)

For patients with acute type A aortic dissection, strongly suspected of having concomitant severe coronary artery disease (CAD), preoperative or intraoperative coronary angiography has been recommended. However, conventional selective coronary angiography in this setting may extend the dissection or aortic rupture. We present the use of intraoperative open-heart coronary angiography in a patient with acute type A aortic dissection. A 50-year-old man presented with chest pain and dyspnea and was admitted to our department with acute type A aortic dissection. The patient underwent coronary artery stent implantation in the left anterior descending coronary artery (LAD) 3 years previously due to an acute myocardial infarction. This time we failed to evaluate the patency of the LAD using multidetector computed tomography. An aortic rupture occurred due to conventional coronary angiography, and open-heart coronary angiography was performed. The examination revealed no significant stenosis. A Bentall procedure and total aortic arch replacement were performed, with an intraoperative stent inserted into the descending aorta, and the patient had an uneventful postoperative course. From this case, we learn that intraoperative open-heart coronary angiography is safe and effective in patients with acute type A aortic dissection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Yang, Li, Chen, Sun, Fan and Yu.)

Background: It is unclear whether the total arch replacement (TAR) combined with frozen elephant trunk (FET) implantation and hybrid debranching surgery have a difference in the prognosis of patients with type A acute aortic syndrome (AAS). We attempted to compare the short-term and long-term prognosis of total arch replacement (TAR) combined with frozen elephant trunk (FET) implantation and hybrid debranching surgery in patients with type A acute aortic syndrome (AAS). Methods: From January 2014 to September 2020, a total of 518 patients who underwent TAR with FET surgery and 31 patients who underwent hybrid surgery were included. We analyzed the post-operative mortality and morbidity of complications of the two surgical methods, and we determined 67 patients for subgroup analysis through a 1:2 propensity score match (PSM). We identified risk factors for patient mortality and post-operative neurological complications through multivariate regression analysis. Results: Compared with the TAR with FET group, hybrid surgery could reduce aortic cross-clamp time, reduce intraoperative blood loss and prevent some patients from cardiopulmonary bypass. There was no significant difference in 30-day mortality between the TAR with FET group and the hybrid surgery group (10.6 vs. 9.7%). However, hybrid surgery had increased the incidence of permanent neurological complications in patients (95%CI: 4.7-35.7%, P = 0.001), especially post-operative cerebral infarction ( P < 0.001). During the average follow-up period of 31.6 months, there was no significant difference in the 1-year survival rate and 3-year survival rate between the TAR with FET group and the hybrid surgery group ( P = 0.811), but hybrid surgery increased the incidence of long-term neurological complications ( P < 0.001). In multivariate regression analysis, surgical methods were not a risk factor for post-operative deaths, but hybrid surgery was a risk factor for post-operative neurological complications ( P < 0.001). Conclusions: Hybrid surgery is an acceptable treatment for AAS, and its post-operative mortality is similar to FET. But hybrid surgery may increase the risk of permanent neurological complications after surgery, and this risk must be carefully considered when choosing hybrid surgery., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Li, Li, Wang, Li, Sun, Liu, Fan, Zhang, Zou, Zhang and Gong.)

Background: The consequence of valve malposition (VM) during transcatheter aortic valve replacement (TAVR) can be severe, but the determinants of VM with self-expandable TAVR have not been thoroughly evaluated. We aimed to investigate the anatomical predictors of VM during self-expandable TAVR. Methods: In this multicenter retrospective study, TAVR was performed using the Venus A-Valve. The baseline, computed tomography, and procedural characteristics along with clinical outcomes were collected. Multivariate logistic regression model and receiver operating characteristic (ROC) curve analyses were performed. Results: A total of 84 consecutive patients (23 with VM) were included. Stepwise regression showed that annulus perimeter/left ventricular outflow tract perimeter (AL ratio) and sinotubular junction (STJ) height were predictors of VM. The ROC curve indicated a moderate strength of AL ratio [area under the curve (AUC) 0.71, cutoff 0.96] and a weak strength of STJ height (AUC 0.69, cutoff 23.8 mm) to predict VM. The combination of both predictors revealed a higher predictive value of VM (AUC 0.77). In multivariate analysis, AL ratio <0.96 [odds ratio (OR) 3.98, p = 0.015] and STJ height ≥23.8 mm (OR 4.63, p = 0.008) were strong independent predictors of VM. The presence of both predictors was associated with a very high risk of VM (OR 10.67, p = 0.002). The rate of moderate-to-severe paravalvular regurgitation was higher in patients with VM at 30 days (26.1 vs. 4.9%, p = 0.011). Conclusions: A conical left ventricular outflow tract and tall aortic sinuses were strong anatomical predictors of VM during self-expandable TAVR., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Li, Sun, Zheng, Li, Dong, Fu, Mo, Li, Liu, Xu, Zhang, Cao, Fan, Lim and Luo.)

Background: Patients with acute type A aortic dissection are usually transferred to the intensive care unit (ICU) after surgery. Prolonged ICU length of stay (ICU-LOS) is associated with higher level of care and higher mortality. We aimed to develop and validate machine learning models for predicting ICU-LOS after acute type A aortic dissection surgery. Methods: A total of 353 patients with acute type A aortic dissection transferred to ICU after surgery from September 2016 to August 2019 were included. The patients were randomly divided into the training dataset (70%) and the validation dataset (30%). Eighty-four preoperative and intraoperative factors were collected for each patient. ICU-LOS was divided into four intervals (<4, 4-7, 7-10, and >10 days) according to interquartile range. Kendall correlation coefficient was used to identify factors associated with ICU-LOS. Five classic classifiers, Naive Bayes, Linear Regression, Decision Tree, Random Forest, and Gradient Boosting Decision Tree, were developed to predict ICU-LOS. Area under the curve (AUC) was used to evaluate the models' performance. Results: The mean age of patients was 51.0 ± 10.9 years and 307 (87.0%) were males. Twelve predictors were identified for ICU-LOS, namely, D-dimer, serum creatinine, lactate dehydrogenase, cardiopulmonary bypass time, fasting blood glucose, white blood cell count, surgical time, aortic cross-clamping time, with Marfan's syndrome, without Marfan's syndrome, without aortic aneurysm, and platelet count. Random Forest yielded the highest performance, with an AUC of 0.991 (95% confidence interval [CI]: 0.978-1.000) and 0.837 (95% CI: 0.766-0.908) in the training and validation datasets, respectively. Conclusions: Machine learning has the potential to predict ICU-LOS for acute type A aortic dissection. This tool could improve the management of ICU resources and patient-throughput planning, and allow better communication with patients and their families., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Chen, Zhang, Yang, Mo, Zhang, Li, Chen, Fang, Wang, Huang, Fan and Zhang.)

Objective: To investigate the N6-methyladenosine (m6A) modification and the expressions of the m6A regulatory genes in the acute aortic dissection (AD). Methods: MeRIP-seq and RNA-seq experiments of aortic media tissue samples obtained from AD ( n = 4) and Controls ( n = 4) were conducted. m6A methylation quantification was used to measure the total mRNA m6A level. The five m6A regulators mRNA expressions were analyzed by quantitative polymerase chain reaction (qPCR). Western blot analyses and immunofluorescence staining were used to detect the difference of METTL14 protein expression in the aortas of AD and Normal. Results: Among AD patients, we detected significantly elevated levels of m6A in total RNA. Compared with the normal group, the up methylated coding genes of AD were primarily enriched in the processes associated with extracellular fibril organization, while the genes with down methylation were enriched in the processes associated with cell death regulation. Furthermore, many differentially methylated m6A sites (DMMSs) coding proteins were mainly annotated during the extracellular matrix and inflammatory responses. Conclusions: These findings indicate that differential m6A methylation and m6A regulatory genes, including MTEEL14 and FTO, may act on functional genes through RNA modification, thereby regulating the pathogenesis of aortic dissection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhou, Chen, Zhou, Liu, Fan and Sun.)