This study developed a set of Role-playing game (RPG), which was used to explore whether significant differences exist in academic performance and learning attitudes between RPG-based assessment and traditional lectures. This study also investigated the satisfaction of students toward the RPG scenario. Research participants included 100 second grade elementary students. The experimental results showed the different teaching methods affected the academic performance and learning attitude of second grade elementary students in fraction concepts. Learning by using RPG-based assessment can effectively improve the academic performance and learning attitudes of students. Students with high learning achievement were most satisfied with the RPG-based assessment scenarios, whereas those with low learning achievement demonstrated low levels of satisfaction. It is hoped that the innovative learning method provided by this study will help students.
Mesenchymal stem cells (MSCs) are known to play a role in postnatal vasculogenesis and hold great promise for vascular regeneration. However, the mechanisms by which the endothelial differentiation and specification of MSCs remain unclear. We examined the potential role and molecular mechanisms of atypical chemokine receptor ACKR3/ CXCR7 in MSC-mediated endothelial cell differentiation and specification. Here, we showed that vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) activate CXCR7 expression on MSCs through PDGF receptors, PDGFRα and PDGFRβ-mediated phosphoinositide 3-kinase (PI3K)/Akt signaling. Genetic and pharmacologic blockage of CXCR7 on MSCs suppressed the VEGF or stromal cell-derived factor 1 (SDF)-1-induced the capacity for vasculogenesis in vitro and in vivo. Moreover, CXCR7 gain of function markedly promoted vasculogenesis by MSCs in vitro and in vivo and induced endothelial differentiation along the arterial endothelial cell lineage via upregulation of Notch signaling. However, blockade of Notch signaling inhibited CXCR7-induced vasculogensis by MSCs. These results indicate CXCR7 is a critical regulator of MSC-mediated postnatal vasculogenesis and arterial specification via Notch signaling.
Background. To investigate the possibility of cryopreservation of spermatozoa obtained from percutaneous epididymal sperm aspiration (PESA) in patients with obstructive azoospermia and the feasibility of intentional dissociation of PESA and intracytoplasmic sperm injection (ICSI) cycles. Methods. Fifty-six patients with obstructive azoospermia underwent diagnostic PESA before ovarian stimulation. If spermatozoa were found, they were frozen for subsequent ICSI. The outcome was compared with 17 fresh PESA/ICSI cycles. Results. Among the 56 patients, diagnostic PESA obtained spermatozoa in 51 patients. The mean motility of the spermatozoa decreased from 15.2% to 4.2% after freezing and thawing. These patients underwent 96 frozen PESA/ICSI cycles. The rates of fertilization, implantation and clinical pregnancy for frozen-thawed spermatozoa (71.6, 14.0 and 40.6%, respectively) were similar to those for fresh spermatozoa (69.2, 13.2 and 41.2%, respectively). Conclusions. Sufficient numbers of spermatozoa can be obtained for cryopreservation through PESA and the spermatozoa work well after thawing. The strategy of performing diagnostic PESA before ovarian stimulation and freezing the recovered spermatozoa for subsequent ICSI is feasible for patients with obstructive azoospermia.
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