Bone-marrow-derived mesenchymal stem cells (MSCs) can differentiate into a variety of cell types including smooth muscle cells (SMCs). We have attempted to demonstrate that, following treatment with transforming growth factor-beta 1 (TGF-beta1) and ascorbic acid (AA), human bone-marrow-derived MSCs differentiate into the SMC lineage for use in tissue engineering. Quantitative polymerase chain reaction for SMC-specific gene (alpha smooth muscle actin, h1-calponin, and SM22alpha) expression was performed on MSCs, which were cultured with various concentrations of TGF-beta1 or AA. TGF-beta1 had a tendency to up-regulate the expression of SMC-specific genes in a dose-dependent manner. The expression of SM22alpha was significantly up-regulated by 30 microM AA. We also investigated the additive effect of TGF-beta1 and AA for differentiation into SMCs and compared this effect with that of other factors including platelet-derived growth factor BB (PDGF-BB). In addition to SMC-specific gene expression, SMC-specific proteins increased by two to four times when TGF-beta1 and AA were used together compared with their administration alone. PDGF did not increase the expression of SMC-specific markers. MSCs cultured with TGF-beta1 and AA did not differentiate into osteoblasts and adipocytes. These results suggest that a combination of TGF-beta1 and AA is useful for the differentiation of MSCs into SMCs for use in tissue engineering.

Background: Bone marrow-derived mesenchymal stem cells (MSCs) can differentiate into various types of cell, and the extracellular matrix (ECM) is acknowledged to be important for the regulation of cell functions. In this study, we demonstrated the effects of ECMs on the differentiation of human bone marrow-derived MSCs into a smooth muscle cell (SMC) lineage. Methods: Human MSCs (hMSCs) were cultured on dishes coated with 3 types of ECM including laminin (LM), collagen type IV (Col-IV) and fibronectin for 7 days, and simultaneously cultured on a noncoated dish as a control. Cell numbers of these cultured hMSCs were counted, and their expression of SMC-specific genes and proteins was evaluated. hMSCs were then seeded on LM-coated biodegradable sheets and implanted into rat subcutaneous space. After 2 weeks of implantation, these tissues were evaluated. Results: The number of hMSCs was significantly increased by culture on Col-IV-coated dishes. The expression of SMC-specific genes and proteins (α-smooth muscle actin, ASMA; h1-calponin, CALP) in hMSC was significantly upregulated from culture on LM-coated dishes. LM-coated sheets showed a significantly increased expression of ASMA and CALP protein in vivo. Moreover, a fully differentiated marker (SM2) was expressed in the in vivo implanted hMSCs in the course of 2 weeks on the LM-coated sheet. Conclusion: These results suggest that the signal transduction of the cell-matrix interaction for the differentiation of hMSCs into SMCs was activated when cultured with LM. LM-coated materials may thus be useful for cardiovascular tissue engineering.

Cultured periodontal ligament-derived cells were a morphologically homogeneous population, although expression of STRO-1 was limited in primary culture. Cultured cells showed de-differentiation during passage for both osteogenesis- and tendo/ligamentogenesis-related genes.

Background: No previous population-based studies have examined associations between self-cutting, perceived school safety, and bullying behavior among East Asian adolescents. Method: We examined whether bullying, victimization, and perceived school safety were associated with self-cutting by getting 1865 students with a mean age of 13.9 years (standard deviation 0.2 years) to complete questions on these variables. Psychiatric problems were assessed with the Strengths and Difficulties Questionnaire. Results: About 5.6% of males and 11.9% females had practiced self-cutting and when we controlled these results for psychiatric symptoms, self-cutting was associated with being both a bully and a victim among males and females. In addition, self-cutting was independently associated with perceived school safety among females. Those who felt unsafe at school and were victimized were much more likely to engage in self-cutting. Conclusions: Self-cutting among Japanese adolescents was linked with bullying behavior and feeling unsafe at school. Secure school environments and school-based antibullying programs could help to prevent adolescent self-injurious behavior. Key Practitioner Message• Self-cutting has been observed among adolescents, with females engaging in self-harm more frequently than males, and this is of clinical concern.• Being a bully and a victim of bullying have been strongly associated with self-cutting in both male and female adolescents.• Schools can help to reduce the incidence of self-cutting by providing a safe environment and providing antibullying programs.

Tacrolimus-eluting biodegradable nanofiber reduced neointimal hyperplasia and preserved endothelialization. This device may be useful in the prevention of anastomotic stricture.