Objective To explore the experiences of master degree nursing students and their supervisors under the dual-supervisor system.Methods A phenomenological research was adopted in this study eighteen master degree nursing students,five principle supervisors and four assistant supervisors from our university were selected through purposive sampling for semi-structured interviews between July and September 2023.Data acquired from the interviews was analysed using Colaizzi's method to summarise and extract the themes.Results Three main themes and eleven sub-themes were extracted,including the collaborative framework of the dual-mentor system(discrepancies in the perception of the dual-mentor system between faculty and students,the selection and matching process for associate mentors,the division of responsibilities and collaborative dynamics between primary and associate mentors,student-centered personalized training strategies,context-specific guidance provided by associate mentors,and the extent to which inter-role communication relies on student initiative),the benefits of the dual-mentor system(encompassing diversified academic and professional guidance,as well as integrated theoretical and practical support)and the expectations held by faculty and students regarding the dual-mentor system(refining institutional design and reinforcing accountability,enhancing the support infrastructure for associate mentors,and improving the tripartite communication mechanism among faculty,students,and associate mentors).Conclusion In nursing postgraduate education,the roles and responsibilities within the dual-mentor system can be more clearly delineated,and inter-mentor collaboration should be further strengthened.It is recommended to enhance tripartite communication among faculty,students,and associate mentors to foster the effective implementation and development of the dual-mentor system.

Objective To explore the experiences of master degree nursing students and their supervisors under the dual-supervisor system.Methods A phenomenological research was adopted in this study eighteen master degree nursing students,five principle supervisors and four assistant supervisors from our university were selected through purposive sampling for semi-structured interviews between July and September 2023.Data acquired from the interviews was analysed using Colaizzi's method to summarise and extract the themes.Results Three main themes and eleven sub-themes were extracted,including the collaborative framework of the dual-mentor system(discrepancies in the perception of the dual-mentor system between faculty and students,the selection and matching process for associate mentors,the division of responsibilities and collaborative dynamics between primary and associate mentors,student-centered personalized training strategies,context-specific guidance provided by associate mentors,and the extent to which inter-role communication relies on student initiative),the benefits of the dual-mentor system(encompassing diversified academic and professional guidance,as well as integrated theoretical and practical support)and the expectations held by faculty and students regarding the dual-mentor system(refining institutional design and reinforcing accountability,enhancing the support infrastructure for associate mentors,and improving the tripartite communication mechanism among faculty,students,and associate mentors).Conclusion In nursing postgraduate education,the roles and responsibilities within the dual-mentor system can be more clearly delineated,and inter-mentor collaboration should be further strengthened.It is recommended to enhance tripartite communication among faculty,students,and associate mentors to foster the effective implementation and development of the dual-mentor system.

Objective To assess with machine learning the predictive value of mechanomics derived from coronary CT angiography(CCTA)for atherosclerotic plaque formation in regions proximal to myocardial bridging(MB)in the left anterior descending coronary artery(LAD).Methods This retrospective study included a cohort of patients with MB in LAD and no atherosclerotic plaque formation in LAD as confirmed by two CCTA conducted between January 2007 and April 2021 at our hospital.The interval between the two CCTA examinations was more than 3 months.The primary endpoint was the formation of atherosclerotic plaques in regions proximal to the myocardial bridging.Patient demographic characteristics and clinical risk factors were documented.Then,the patients were matched by age and sex in a 1-to-1 ratio and divided into two groups,those with plaque formation and those without plaque formation.Computational fluid dynamics analysis was performed based on CCTA.Key anatomical parameters of MB,including location,length,depth,and systolic compression index,were meticulously measured on the CCTA images.Mechanomic data were extracted from the region proximal to the MB.A multivariate Cox regression analysis was performed to identify significant features.A random forest algorithm was used to select mechanomic features for subsequent modeling and to assign scores for each patient's mechanomic features.The log-rank test and Kaplan-Meier curves were used to investigate the mechanomic model's predictive performance concerning plaque formation.Additionally,the operator characteristic curves were applied to evaluate how well the model could predict plaque formation across various myocardial bridge subgroups.Results A total of 104 patients with LAD MB were recruited.The mean age of the subjects were(54.56±10.56)years and 75.00％(78/104)of them were male.Among them,52 developed plaque formation over a median follow-up period of 3.0 years.Apart from a smoking history,which was more prevalent in the group with plaque formation than that in the group without plaque formation(21.15％vs.5.77％,P=0.04),no significant differences between the groups were observed in terms of the other clinical or anatomical characteristics(all P≤0.05).The participants were divided into a training set(n=74)and a validation set(n=30)at a 7∶3 ratio.With the mechanomics model constructed using the random forest algorithm,the patients were classified into a high-score group(≥0.46)and a low-score group(＜0.46)based on a cutoff score of 0.46.The mechanomics model achieved a sensitivity of 0.87(0.58-0.98)and an accuracy of 0.63(0.44-0.79)in the validation set.The multivariate Cox regression model revealed a strong positive association between mechanomics and plaque formation(hazards ratio[HR]:10.58;95％confidence interval[CI]:3.23-34.64,P＜0.001).The log-rank test showed that the high-score group in the mechanomics model was more likely to develop plaques at the proximal regions of the myocardial bridge compared to the low-score group(P＜0.001).The area under the curve(AUC)for plaque formation,as predicted by the model,was 0.88(95％CI:0.82-0.95)for the entire population,0.89(95％CI:0.82-0.96)for the training set,0.86(95％CI:0.74-0.99)for the validation set,0.92(95％CI:0.86-0.97)for the superficial MB group,0.86(95％CI:0.74-0.98)for the long MB group,and 0.91(95％CI:0.83-0.98)for the short MB group.Conclusion The mechanomic assessment holds substantial potential as a predictive tool for atherosclerotic plaque formation in regions proximal to MB in LAD.

Aristolochic acid (AA), extracted from Aristolochiaceae plants, plays an essential role in traditional herbal medicines and is used for different diseases. However, AA has been found to be nephrotoxic and is known to cause aristolochic acid nephropathy (AAN).AA-induced acute kidney injury (AKI) is a syndrome in AAN with a high morbidity that manifests mitochondrial damage as a key part of its pathological progression. Melatonin primarily serves as a mitochondria-targeted antioxidant. However, its mitochondrial protective role in AA-induced AKI is barely reported. In this study, mice were administrated 2.5 mg/kg AA to induce AKI. Melatonin reduced the increase in Upro and Scr and attenuated the necrosis and atrophy of renal proximal tubules in mice exposed to AA. Melatonin suppressed ROS generation, MDA levels and iNOS expression and increased SOD activities in vivo and in vitro. Intriguingly, the in vivo study revealed that melatonin decreased mitochondrial fragmentation in renal proximal tubular cells and increased ATP levels in kidney tissues in response to AA. In vitro, melatonin restored the mitochondrial membrane potential (MMP) in NRK-52E and HK-2 cells and led to an elevation in ATP levels. Confocal immunofluorescence data showed that puncta containing Mito-tracker and GFP-LC3A/B were reduced, thereby impeding the mitophagy of tubular epithelial cells. Furthermore, melatonin decreased LC3A/B-II expression and increased p62 expression. The apoptosis of tubular epithelial cells induced by AA was decreased. Therefore, our findings revealed that melatonin could prevent AA-induced AKI by attenuating mitochondrial damage, which may provide a potential therapeutic method for renal AA toxicity.

The incidence of valvular heart disease (VHD) increases with age, and its principal therapy is valve replacement. However, in recent years, the emergence of transcatheter interventions has changed the traditional therapy, making high-risk patients of surgery see dawn of hope. 3D printing technology has developed rapidly since it was applied to the medical field in 1990. Moreover, it has been widely applied in many surgical majors via refined reduction technology. However, the application of 3D printing technology in cardiovascular surgery is still in the preliminary stage, especially in the field of VHD. This article aims to review basic principles of 3D printing technology, its advantages in the therapy of VHD, and its current status of clinical application. Furthermore, this article elaborates current problems and looks forward to the future development direction.

Objective    To evaluate the clinical value of three-dimensional (3D) printing model in accurate and minimally invasive treatment of double outlet right ventricle (DORV). Methods    From August 2018 to August 2019, 35 patients (22 males and 13 females) with DORV aged from 5 months to 17 years were included in the study. Their mean weight was 21.35±8.48 kg. Ten patients who received operations guided by 3D printing model were allocated to a 3D printing model group, and the other 25 patients who received operations without guidance by 3D printing model were allocated to a non-3D printing model group. Preoperative transthoracic echocardiography and CT angiography were performed to observe the location and diameter of ventricular septal defect (VSD), and to confirm the relationship between VSD and double arteries. Results    The McGoon index of patients in the 3D printing model group was 1.91±0.70. There was no statistical difference in the size of VSD (13.20±4.57 mm vs. 13.40±5.04 mm, t=−0.612, P=0.555), diameter of the ascending aorta (17.10±2.92 mm vs. 16.90±3.51 mm, t=0.514, P=0.619) or diameter of pulmonary trunk (12.50± 5.23 mm vs. 12.90±4.63 mm, t=−1.246, P=0.244) between CT and 3D printing model measurements. The Pearson correlation coefficients were 0.982, 0.943 and 0.975, respectively. The operation time, endotracheal intubation time, ICU stay time and hospital stay time in the 3D printing model group were all shorter than those in the non-3D printing model group (P<0.05). Conclusion    The relationship between VSD and aorta and pulmonary artery can be observed from a 3D perspective by 3D printing technology, which can guide the preoperative surgical plans, assist physicians to make reasonable and effective decisions, shorten intraoperative exploration time and operation time, and decrease the surgery-related risks.

Objective:To investigate the effects of different surface treatments protocol on the bonding strength between lithium disilicate glass ceramic and resin cements.Methods:Ceramic specimens of 15 mm×13 mm×3 mm were used to evaluate the effects of different surface treatments of hydrofluoric acid etching and silane coupling in current research. Firstly, the standard lithium ceramic specimens were divided into 8 groups ( n=16), and were etched by 4.5% hydrofluoric acid for 0, 10, 20, 30, 40, 60, 120 and180 s. Then specimens in each group was further divided into two sub-groups. In one sub-group specimens were coated with coupling agents and in the other were not. Shear bonding strength (SBS) and failure mode were tested and analyzed. The surface morphologies of hydrofluoric acid-etched ceramic specimens were observed by the scanning electron microscopy (SEM). Secondly, after being etched by 4.5% hydrofluoric acid for 30 s, the lithium ceramic specimens were coated with coupling agents at different temperatures: room temperature (12 ℃) for 60 s, 60 ℃ hot air for 60 s and 100 ℃ hot air for 60 s ( n=8). SBS and fracture mode were tested and analyzed. The infrared spectrum analysis was used to characterize the coupled surfaces of the ceramic samples. Results:The maximum SBS values were obtained after the specimens were etched for 30 s. The silane coupled group showed a higher SBS value [(25.91±4.30) MPa, P<0.05] than the no-silane-coupled group [(20.27±4.92) MPa]. SBS decreased with extended etching time (>30 s) and the SEM photos showed over-etching morphologies. The 60 ℃ hot air treatment resulted in the maximum SBS value [(28.70±5.32) MPa] than that of the room temperature [(20.08±3.64) MPa] or 100 ℃ hot air [(25.64±4.86) MPa, P<0.05]. And the cohesive failure mode was found in 60 ℃ hot air treatment group. The infrared spectroscopy analysis showed the highest amount of silicon oxide bond in the 60 ℃ hot air treatment group. Conclusions:In this study, for this product, the optimum etching time of 4.5% hydrofluoric acid was 30 s. Furthermore, an ideal SBS value could be obtained when the silane coupling agents were applied additionally. SBS could be increased substantially when the 30 s-etched-ceramic product was coated with silane coupling agents at 60 ℃ hot air for 60 s.

Nearly a decade of curriculum update in American medical colleges and universities are summarized in this paper. This paper introduces the situation of sampling survey of colleges and universities. The results show the diversity of medical curriculum integration, reflecting the concept of multi-disciplinary integration of basic disciplines, clinical disciplines and public health and social sciences, and giving experiences such as early clinical practice, providing personalized talent cultivation approaches, and designing competency-oriented curriculum system. Combined with the current situation of medical education curriculum reform in China, it's suggested to explore the construction of medical curriculum system with Chinese characteristics, so as to contribute to the cultivation of excellent physicians for implementing Healthy China Initiative.

Objective:To observe the efficacy and safety of urokinase arterial thrombolysis in the treatment of central retinal artery occlusion (CRAO) at different time window.Methods:A retrospective study. From January 2014 to November 2019, 157 eyes (157 CRAO patients) in the Xi’an People's Hospital (Xi’an Fourth Hospital) were included in the study. There were 120 males and 37 females, with the average age of 54.87±12.12 years. The mean onset time was 65.66±67.44 h. All patients were tested with BCVA using international standard visual acuity chart, and the results were converted into logMAR visual acuity record. The arm-retinal circulation time (A-Rct) and the filling time (FT) of retinal arterial trunk-terminal filling time were measured by FFA. The mean logMAR BCVA was 2.44±0.46, the mean A-Rct and FT were 27.72±9.78 and 13.58±14.92 s respectively. According to the time window, the patients were divided into the onset 3-72 h group and the onset 73-240 h group, which were 115 patients and 42 patients respectively. There were no statistically significant difference between the 3-72 h group and the 73-240 h group in age, A-Rct and LogMR BCVA before treatment ( χ2=-0.197, -1.242, -8.990; P=0.844, 0.369, 0.369); the difference was statistically significant in FT comparison ( χ2=-3.652, P=0.000). Urokinase artery thrombolytic therapy was performed at different time window of 3-24 h, 25-72 h, 73-96 h, 97-120 h, 121-240 h after the onset of onset. Age and A-Rct of patients with different treatment time windows were compared, and the differences were not statistically significant ( χ2=6.588, 6.679; P=0.253, 0.246).In comparison of FT and logMAR BCVA, the difference was statistically significant ( χ2 =30.150, 71.378; P=0.000, 0.000). FFA was rechecked 24 hours after treatment, BCVA was rechecked 30 days after treatment. The changes of A-Rct, FT and BCVA before and after treatment were compared and analyzed. The occurrence of adverse reactions during and after treatment were observed. The two groups of measurement data were compared. The t test was used for those with normal distribution and χ2 test was used for those with non-normal distribution. Spearman correlation analysis was used to analyze the correlation between onset time and the difference of A-Rct, FT shortening time and logMAR BCVA after treatment. Results:At 24 h after CRAO treatment, A-Rct and FT of 157 cases were 19.64±6.50 and 6.48±7.36 s respectively, which were significantly shorter than those before treatment, and the differences were statistically significant ( χ2=-16.236, -14.703; P=0.000, 0.000). The logMAR BCVA at 30 d after treatment was 1.72±0.76, which was significantly higher than that before treatment. The difference was statistically significant ( χ2=-14.460, P=0.000). After CRAO urokinase arterial thrombolysis at different time window, there were statistically significant differences in A-Rct shortening time, FT shortening time, and logMAR BCVA difference ( χ2=12.408, 24.200, 104.388; P=0.030, 0.000, 0.000). There was no statistically significant difference between the 3-72 h group and the 73-240 h group ( χ2 =-1.042, P=0.297) in shortening time of A-Rct after treatment. The difference of FT shortening time was statistically significant ( χ2=-3.581, P=0.000). The difference of logMAR BCVA was statistically significant ( χ2=-9.905, P=0.000). The results of Spearman correlation analysis showed that there was no correlation between the onset time and the shortening time of A-Rct and FT after treatment ( rp=-0.040, -0.081; P=0.436, 0.115), and negative correlation with the logMAR BCVA difference ( rp=-0.486, P=0.000). One case of intracranial hemorrhage occurred after treatment, and it improved after dehydration to reduce cerebral edema, scavenging free radicals and brain protection. Conclusions:Urokinase arterial thrombolytic therapy is effective for CRAO within time window of 3-240 h, A-Rct, FT and LogMRA BCVA are all improved. However, with the prolongation of thrombolytic therapy time window, the therapeutic effect of urokinase arterial thrombolytic therapy is decreased. The therapeutic effect of Urokinase arterial thrombolytic therapy was better within 72 h.

Objective To evaluate the accuracy and clinical significance of the vesical imagingreporting and data system (Ⅵ-RADS) in predicting muscle-invasive bladder cancer (MIBC).Methods The data of 59 bladder cancer patients who underwent multiparametric magnetic resonance imaging and surgery between 2014 March and 2019 May were retrospectively analyzed,which includes 51 males and 8 females,aged 36-82 years old,with a median age of 62 years old.According to the scoring methods specified by Ⅵ-RADS,radiologists read and scored all mpMRIs including T2-weighted imaging (T2WI),diffusion-weighted imaging(DWI),and dynamic contrast enhancement MRI(DCE-MRI) of all the included patients.And then the Ⅵ-RADS were compared with pathological diagnosis.Proportions of MIBC in each score category were calculated,and ROC curve was plotted and the area under the curve (AUC) was estimated to assess the sensitivity and specificity of Ⅵ-RADS in diagnosing MIBC.Results The number of patients in Ⅵ-RADS score category 1 to 5 were 12,28,2,15 and 2,respectively.And there were 0,2 (7.4％),1 (50.0％),13 (81.3 ％),2 (100.0％) MIBC patients in each score category,respectively.When Ⅵ-RADS ≥3 was used to define MIBC,it came to the largest Youden's Index(0.7913),with an AUC of 0.924.And the sensitivity and specificity were 88.9％ and 90.2％,respectively.Conclusions Ⅵ-RADS has high accuracy in predicting MIBC,and it is worthy of application and verification in further clinical practice.The urologists should be highly alert to the existence of MIBC when Ⅵ-RADS ≥3.