Four-dimensional echocardiography with B-flow imaging and spatiotemporal image correlation in the assessment of congenital heart defects

Study on the Application Value of PBL Combined with Situational Simulation Teaching Method in Clinical Practice Teaching of Radiology Department

Objective. To study the application value of PBL (Problem-Based Learning) combined with a situational simulation teaching method in clinical practice teaching of radiology. Methods. 120 interns who practiced in the radiology department of our hospital from 2020 to 2021 were randomly divided into a study group and a control group. The research group used PBL combined with the scenario simulation teaching method to carry out clinical practice teaching activities. The control group was carried out according to the conventional teaching plan. After 3 months, the teaching effect and satisfaction of the two groups were compared. Results. The imaging report quality control score, intravenous contrast agent score, and practice test score in the study group were higher than those in the control group. The scores of the small class and special class in the research group were higher than those in the control group, and the difference was statistically significant ( $P<0.05$ ). The scores of job competency questionnaire in the research group were higher than those in the control group ( $P<0.05$ ). The occupational self-efficacy questionnaire score of the research group was higher than that of the control group ( $P<0.05$ ). The nursing practice satisfaction score of the research group was higher than that of the control group ( $P<0.05$ ). Conclusion. The value of PBL combined with the scenario simulation teaching method in the teaching of radiology clinical practice is significant, which can improve the work ability of interns and make them more satisfied.

Pro-BDNF Contributes to Hypoxia/Reoxygenation Injury in Myocardial Microvascular Endothelial Cells: Roles of Receptors p75NTR and Sortilin and Activation of JNK and Caspase 3

The aim of this study was to identify the role of the precursor of the brain-derived neurotrophic factor (pro-BDNF) in myocardial hypoxia/reoxygenation injury (H/R) and to address the underlying mechanisms. For this purpose, myocardial microvascular endothelial cells (MMECs) exposed to a high concentration of glucose (30 mM) for 48 h were subjected to 4 h of hypoxia followed by 2 h of reoxygenation. Terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) staining and flow-cytometric analysis were performed to detect apoptosis. Cell scratch and capillary-like-structure formation assays were employed to evaluate cell function. The levels of apoptosis-related proteins were evaluated by Western blotting and immunofluorescence assays. Our results showed that H/R resulted in MMEC injury, as indicated by significant increases in TUNEL-positive cell numbers and a reduction in MMEC migration and in capillary-like-structure formation coupled with increased pro-BDNF protein expression. In addition, overexpression of pro-BDNF in MMECs via a viral vector led to increased pro-BDNF expression, and this upregulation induced apoptosis. Mechanistic experiments revealed that H/R did not influence BDNF, JNK, and caspase 3 expression, but upregulated pro-BDNF, p75^NTR, sortilin, phospho-JNK, and cleaved caspase 3 protein levels. In contrast, neutralization of endogenous pro-BDNF with an antibody significantly attenuated H/R-induced upregulation of pro-BDNF, p75^NTR, sortilin, p-JNK, and cleaved caspase 3 protein levels, indicating that p75^NTR-sortilin signaling and activation of JNK and caspase 3 may be involved in these effects. In conclusion, H/R-induced injury may be mediated by pro-BDNF, at least in part through the regulation of p75^NTR-sortilin signaling and activation of JNK and caspase 3.

The value of 3D and 4D assessments of the fetal heart

The objective of this review was to demonstrate the main tools of three- and four-dimensional ultrasonography, using the spatiotemporal image correlation software and its respective applications for assessing the fetal heart and its vascular connections, along with its potential contribution towards screening for congenital heart diseases. Today, conventional, two-dimensional, echocardiography continues to be the gold standard for diagnosing congenital heart diseases. However, recent studies have demonstrated that spatiotemporal image correlation offers some advantages that boost two-dimensional accuracy in detecting congenital heart diseases, given that the fetal heart assessment can be completed in the absence of the patient (offline) and be discussed by different examiners. Additionally, data volumes can be sent for analysis in reference centers via internet links. Spatiotemporal image correlation also enables direct measurement of heart structures in rendering mode, such as the interventricular septum and the annulus of the atrioventricular valves. Furthermore, it enables assessment of cardiac function when used in association with the virtual organ computer-aided analysis software, thus making it possible to calculate the total systolic function, ejection fraction, and cardiac output.