BackgroundEndothelin-1 (ET-1) is synthesized and upregulated in astrocytes under stroke. We previously demonstrated that transgenic mice over-expressing astrocytic ET-1 (GET-1) displayed more severe neurological deficits characterized by a larger infarct after transient middle cerebral artery occlusion (tMCAO). ET-1 is a known vasoconstrictor, mitogenic, and a survival factor. However, it is unclear whether the observed severe brain damage in GET-1 mice post stroke is due to ET-1 dysregulation of neurogenesis by altering the stem cell niche.MethodsNon-transgenic (Ntg) and GET-1 mice were subjected to tMCAO with 1 h occlusion followed by long-term reperfusion (from day 1 to day 28). Neurological function was assessed using a four-point scale method. Infarct area and volume were determined by 2,3,5-triphenyltetra-zolium chloride staining. Neural stem cell (NSC) proliferation and migration in subventricular zone (SVZ) were evaluated by immunofluorescence double labeling of bromodeoxyuridine (BrdU), Ki67 and Sox2, Nestin, and Doublecortin (DCX). NSC differentiation in SVZ was evaluated using the following immunofluorescence double immunostaining: BrdU and neuron-specific nuclear protein (NeuN), BrdU and glial fibrillary acidic protein (GFAP). Phospho-Stat3 (p-Stat3) expression detected by Western-blot and immunofluorescence staining.ResultsGET-1 mice displayed a more severe neurological deficit and larger infarct area after tMCAO injury. There was a significant increase of BrdU-labeled progenitor cell proliferation, which co-expressed with GFAP, at SVZ in the ipsilateral side of the GET-1 brain at 28 days after tMCAO. p-Stat3 expression was increased in both Ntg and GET-1 mice in the ischemia brain at 7 days after tMCAO. p-Stat3 expression was significantly upregulated in the ipsilateral side in the GET-1 brain than that in the Ntg brain at 7 days after tMCAO. Furthermore, GET-1 mice treated with AG490 (a JAK2/Stat3 inhibitor) sh owed a significant reduction in neurological deficit along with reduced infarct area and dwarfed astrocytic differentiation in the ipsilateral brain after tMCAO.ConclusionsThe data indicate that astrocytic endothelin-1 overexpression promotes progenitor stem cell proliferation and astr ocytic differentiation via the Jak2/Stat3 pathway.

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Background: The aim of the study was to probe the morphological features of the proximal segment (V1) of vertebral artery (VA) in a sample of Chinese cadavers. Materials and methods: The origin, course and outer diameter at origin of the pre-vertebral part of the VAs were evaluated in 119 adult cadavers. Results: It was found that 94.12% of the VAs originated from the subclavian arteries, bilaterally. The variant origins were present in 5.88% of the cadavers and all originated directly from the arch of the aorta. All the variations were observed on the left side of male cadavers. The average outer diameters at origin of the normal and variation groups were 4.35 ± 1.00 mm and 4.82 ± ± 1.42 mm, respectively, p = 0.035. In the normal group, but not in the variation group, the average diameter in the males was significantly larger than that in the females (4.50 ± 0.99 mm, 3.92 ± 0.92 mm, respectively, p = 0.000). In addition, only 5 cadavers in the normal group had hypoplastic VAs (4.20%, 4 males,. Vertebral artery dominance (VAD) was present in 91 (69 males) out of 112 cadavers and more common on the left (n = 48). In addition, 3 cadavers satisfied conditions for coexistence of VAD and vertebral artery hypoplasia. All 7 cadavers in the variation group exhibited VAD, which was more common on the right side (n = 5). Conclusions: The morphologic variations and frequencies described above have implications for the early prevention, abnormal anatomy detection, accurate diagnosis, safe surgery and endovascular treatment of cardiovascular and neurological disease. (Folia Morphol 2019; 78, 4: 710-719)

Medical students' motivation and study strategies are crucial in determining academic performance. This study aimed to assess the motivation and learning strategies of medical students as well as their association with performance in anatomy examinations. The Motivated Strategies for Learning Questionnaire, two focus group discussions, and students' current anatomy cumulative grade point average (cGPA) were used. Generally, the medical students strongly felt that anatomy is fundamental to the practice of medicine and surgery. This result was consistent with high task value scores of 5.99 ± 1.25. They were also driven by extrinsic goal orientation (5.59 ± 1.42) and intrinsic goal orientation (5.08 ± 1.26). Most medical students typically relied on elaboration (5.35 ± 1.25) ahead of other cognitive strategies namely rehearsal (5.30 ± 1.11), organization (5.15 ± 1.34), and lowest‐rated critical thinking (4.77 ± 1.19). The students also relied on resource management strategies, effort regulation (5.15 ± 1.20) and time and study environment regulation (5.03 ± 1.03) more than the moderately scored peer learning (4.95 ± 1.50) and help‐seeking (4.95 ± 1.09). In the focus group discussions, students reported that they often narrate or explain to each other what they would have read and understood from anatomy lectures, tutorials, and textbooks. They also bemoaned the lack of institutional support for stress burdens. The motivation and learning strategies subscales were not correlated with anatomy cGPA. Males were driven by extrinsic goals and experienced significantly higher levels of test anxiety than females (P < 0.05). Knowing the motivation and learning strategies students employ early in the medical curriculum can be leveraged to promote self‐directed learning and academic achievement.

The present study evaluated the students' psychological well-being, experiences, performance, and perception of learning regional anatomy remotely. A regional anatomy remote learning curriculum was designed and learning materials were delivered virtually to 120 undergraduate medical students at Jinan University, China. All the students consented and voluntarily participated in this study by completing self-administered online questionnaires including the Zung's Self-Rating Anxiety and Depression Scales at the beginning and end of the learning session. A subset participated in focus group discussions. Most of the students (90.0%) positively evaluated the current distance learning model. More than 80% were satisfied with the content arrangement and coverage. Many students preferred virtual lectures (68.2%) and videos showing dissections (70.6%) during the distance learning sessions. However, writing laboratory reports and case-based learning were the least preferred modes of learning as they were only preferred by 23.2% and 14.1% of the students, respectively. There was no significant lockdown-related anxiety or depression reported by students using depression and anxiety scales as well as feedback from focus group discussions. The surveyed students' confidence scores in distance learning were significantly higher after 5 weeks than at the beginning of the session (3.05 ± 0.83 vs. 3.70 ± 0.71, P < 0.05).Furthermore, the present results showed no significant differences between the current group's academic performance in the unit tests as well as the final overall evaluation for different parts of the course compared to that of the previous year's cohort.The findings above were congruent with focus group discussion data that the use of the online teaching platform for regional anatomy significantly improved the students' confidence in virtual and self-directed learning and did not negatively affect their academic performance.

Anatomy is a challenging preclinical subject owing to the vast amount of information that students need to master. The adoption of relevant study approaches is key to the development of a long-lasting understanding of anatomical subject matter. Phenomenographic educational research describes the medical students as using a variable mix of deep, strategic, and surface approaches to study. Continually assessing students' learning preferences and approaches is crucial for achieving the desired learning outcomes. The approaches to studying anatomy in two groups of first-year Zimbabwean medical students from two newly established medical schools were collected using the Approaches and Study Skills Inventory for Students (ASSIST) instrument and than analyzed. At least 90% of the students believed that anatomy involved reproducing knowledge or personal understanding and development. Overall, the majority of the students adopted deep and strategic approaches, while a distant minority used the surface approach. There was no significant correlation between either the students' sex or age and their preference for a specific approach to studying. The mean anatomy grades for students using a strategic approach were significantly higher than those using deep or surface approaches. The number of strategic learners was double that of deep learners among the high achievers subgroup. The strategic approach positively correlated with performance in examinations. Generally, the students shared a common understanding of the concept of anatomy learning. Studies such as this can assist with the identification of students at risk of failure and empower lecturers to recommend the adoption of more beneficial strategic and deep learner traits. Anat