摘要: The distribution pattern of reptiles in mountainous regions is generally related to altitude. The distribution of viperine species can be limited by elevation. Short-tailed viper snakes (Gloydius saxatilis) of South Korea are found mostly in high elevation mountainous areas, but few studies have evaluated how their distribution relates to elevation gradient. This study was conducted from 2012 to 2013 to investigate the altitudinal distribution of short-tailed viper snakes in mountainous areas and to discover their movement patterns in Cheon-ma Mountain County Park in South Korea. A translocation method utilizing radio-tracking technology was employed to confirm whether their distribution was influenced by altitude. The results showed that most short-tailed vipers were observed in middle and high altitude areas (from 400 m to 800 m), but none were observed in low altitude areas (from 200 m to 400 m). According to the results of the translocation and tracking experiments, the individuals of the translocated group showed a significantly broader home range than those of the control group. In addition, all individuals of the translocated group moved vertically, while most of the control group moved horizontally. Therefore, all translocated individuals tended to move back toward their original habitat, a high elevation area. Consequently, we concluded that the distribution of short-tailed viper snakes was limited by altitude.

摘要: Objectives: Cells in the osteon reside in a curved space, accordingly, the curvature of the microenvironment is an important geometric feature in bone formation. However, it is not clear how curved microstructures affect cellular behaviour in bone tissue. Materials and methods: Rat primary bone marrow mesenchymal stem cells (BMSCs) on wavy microgrooves were exposed to PDMS substrates with various curvatures to investigate alterations in cellular morphology and osteogenic differentiation. Additionally, the expression levels of RhoA and its effectors were examined by immunofluorescence and quantitative PCR to determine the mechanisms of curvature-dependent osteogenic differentiation. Results: Wavy microgrooves caused dramatic nuclear distortion and cytoskeletal remodelling. We detected a noticeable increase in the expression of osteogenic-related genes in BMSCs in wavy microgroove groups, and the maximum expression was observed in the high curvature group. Moreover, immunofluorescent staining and quantitative RT-PCR results for RhoA and its effectors showed that the RhoA/ROCK signalling pathway is associated with curvature-dependent osteogenic differentiation. Conclusions: Our results illustrated that curved microstructures could promote BMSC differentiation to the osteogenic lineage, and the osteogenic effects of higher curvature are more obvious. Wavy microstructures could also influence the RhoA/ROCK pathway. Accordingly, curved microstructures may be useful in bone tissue engineering.