Release of miR-29 Target Laminin C2 Improves Skin Repair.

miRNAs are small noncoding RNAs that regulate mRNA targets in a cell-specific manner. miR-29 is expressed in murine and human skin, where it may regulate functions in skin repair. Cutaneous wound healing model in miR-29a/b1 gene knockout mice was used to identify miR-29 targets in the wound matrix, where angiogenesis and maturation of provisional granulation tissue was enhanced in response to genetic deletion of miR-29. Consistently, antisense-mediated inhibition of miR-29 promoted angiogenesis in vitro by autocrine and paracrine mechanisms. These processes are likely mediated by miR-29 target mRNAs released upon removal of miR-29 to improve cell-matrix adhesion. One of these, laminin (Lam)-c2 (also known as laminin γ2), was strongly up-regulated during skin repair in the wound matrix of knockout mice. Unexpectedly, Lamc2 was deposited in the basal membrane of endothelial cells in blood vessels forming in the granulation tissue of knockout mice. New blood vessels showed punctate interactions between Lamc2 and integrin α6 (Itga6) along the length of the proto-vessels, suggesting that greater levels of Lamc2 may contribute to the adhesion of endothelial cells, thus assisting angiogenesis within the wound. These findings may be of translational relevance, as LAMC2 was deposited at the leading edge in human wounds, where it formed a basal membrane for endothelial cells and assisted neovascularization. These results suggest a link between LAMC2, improved angiogenesis, and re-epithelialization.

Twelve tips to organise a mock OSCE.

The objective structured clinical examination (OSCE) is central to assessing clinical competence in undergraduate and postgraduate exams for medical and allied healthcare professions. A mock OSCE on the other hand is a simulation of the OSCE and a unique learning experience for the examinee. They benefit in a variety of ways; from enhancing their time management skills to receiving feedback that can improve their clinical skills. Unfortunately, opportunities to participate in simulated OSCEs remain limited. Reasons include difficulty in fulfilling organisational requirements and equipment-related costs. Mock OSCEs can be set up by undergraduate students or junior trainees for peers, without senior supervision or direct guidance. This article will discuss 12 tips regarding the arrangement of mock OSCEs to guide organisers, including accessing resources and establishing the content of the exam.

Spatio-temporal regulation of gene expression defines subpopulations of epidermal stem cells.

The search for epidermal stem cells has gained the momentum as they possess unique biological characteristics and a potential in regeneration therapies. Several transcription factors and miRNAs have been identified as epidermal stem cell markers. However, the separation of epidermal stem cells from their progeny remains challenging. The introduction of single-cell transcriptomics pointed to the high degree of heterogeneity in epidermal stem cells imbedded within subpopulations of keratinocytes. Pseudotime inference, RNA velocity, and cellular entropy further enhanced our knowledge of stem cells, allowing for the discovery of the epidermal stem cell plasticity. We explore the main findings that lead to the discovery of the plastic trait within the epidermal stem cells and the implications of cell plasticity in regenerative medicine.