How to use Socratic questioning in order to promote adults’ self-directed learning

© 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group. This article discusses the teachers’ role in self-directed learning (SDL)–a central concept in adult education. We explore the use of Socratic questioning to develop critical thinking, which is the outcome of SDL in problem-based learning (PBL). In particular, we analyse 11 adult learners’ reflective journals in relation to a Socratic seminar. Findings showed that adult learners value the mutual relationship between the learner and the teacher in managing the learning process. In addition, we suggest a teaching approach where Socratic questioning can facilitate students’ SDL. We conclude with implications on its use as a means to initiate the learning goals of a PBL tutorial.status: publishe

Effects of donor age, gender, and in vitro cellular aging on the phenotypic, functional, and molecular characteristics of mouse bone marrow-derived mesenchymal stem cells

Mesenchymal stem cells (MSCs) are a very important adult stem cell population with a multitude of potential applications in regenerative medicine. The thorough characterization of the bone marrow MSC (BM-MSC) population derived from the BALB/c species was essential, considering the significance of the murine model amongst animal models. In the present study, we examined the effect of gender, age, and in vitro culture on the basic properties (proliferation, differentiation, and immunosuppressive potential) of BM-MSCs. We found a decline in the progenitor frequencies from the BM of adult mice, lower MSC frequencies in all female donors, and an increase in the BM-MSC proliferation rate upon in vitro propagation. We also examined BM-MSCs for the expression of the 3 major embryonic stem cell transcription factors, Oct3/4, Sox-2, and Nanog, as well as 2 mRNA binding proteins, coding region determinant binding protein/insulin-like growth factor 2 mRNA binding protein 1 (Crd-bp/Imp1) and Deleted in azoospermia-like (Dazl), which are expressed in primitive stem cells, umbilical cord blood-hematopoietic stem cells and amniotic fluid stem cells, respectively. Further, it has been reported that these 2 genes are critical for embryonic development. In this study, therefore, we report, for the first time, the expression of Crd-bp/Imp1 and Dazl in BM-MSCs. Dazl, Oct3/4, and Sox2 were detected in relatively low levels in contrast to Crd-bp/Imp1, its major target c-Myc, as well as Nanog, which were expressed redundantly, irrespective of sex, donor age, or in vitro passaging. These findings could further support the extrinsic theory of aging of the MSC population and the potential implication of embryonic genes in adult stem cell physiology. © Copyright 2011, Mary Ann Liebert, Inc

IGF2BP1 expression in human mesenchymal stem cells significantly affects their proliferation and is under the epigenetic control of TET1/2 demethylases

Mesenchymal stem cells (MSCs) are a population of cells harboring in many tissues with the ability to differentiate toward many different lineages. Unraveling the molecular profile of MSCs is of great importance due to the fact that these cells are very often used in preclinical and clinical studies. We have previously reported the expression of insulin-like growth factor 2 mRNA binding protein 1 (IGF2BP1) an oncofetal mRNA-binding protein - in different stem cell types such as bone marrow (BM)-MSC and umbilical cord blood (UCB)-hematopoietic stem cells. Here, we demonstrate that MSCs of adipose tissue, BM, and UC origin have a differential pattern of IGF2BP1 and ten-eleven-translocate 1/2 (TET1/2) expression that could correlate with their proliferation potential. Upon IGF2BP1 interference, a significant reduction of cell proliferation is observed, accompanied by reduced expression of c-MYC and GLI1 and increased p21. We also present, for the first time, evidence that IGF2BP1 is epigenetically regulated by TET1 and TET2 demethylases. Specifically, we show that TET1 directly binds to the promoter of IGF2BP1 gene and affects the hydroxymethylation status of its promoter. These results indicate that IGF2BP1 and TET1/2 contribute to the stemness of MSCs, at least regarding their proliferative potential. © Mary Ann Liebert, Inc. 2014

Directing mesenchymal stem cells to bone to augment bone formation and increase bone mass

Aging reduces the number of mesenchymal stem cells (MSCs) in the bone marrow which leads to impairment of osteogenesis. However, if MSCs could be directed toward osteogenic differentiation, they could be a viable therapeutic option for bone regeneration. We have developed a method to direct the MSCs to the bone surface by attaching a synthetic high affinity and specific peptidomimetic ligand (LLP2A) against integrin α4β1 on the MSC surface, to a bisphosphonate (alendronate, Ale) that has high affinity for bone. LLP2A-Ale increased MSCs migration and osteogenic differentiation in vitro. A single intravenous injection of LLP2A-Ale increased trabecular bone formation and bone mass in both xenotransplantation and immune competent mice. Additionally, LLP2A-Ale prevented trabecular bone loss after peak bone acquisition was achieved or following estrogen deficiency. These results provide a proof of principle that LLP2A-Ale can direct MSCs to the bone to form new bone and increase bone strength

Myelin-derived and putative molecular mimic peptides share structural properties in aqueous and membrane-like environments

Abstract Background: Despite intense research, the causes of various neurological diseases remain enigmatic to date. A role for viral or bacterial infection and associated molecular mimicry has frequently been suggested in the etiology of neurological diseases, including demyelinating autoimmune disorders, such as multiple sclerosis. Pathogen mimics of myelin-derived autoimmune peptides have been described in the literature and shown to induce myelin autoimmune responses in animal models. Methods: We carried out a structural study on myelin-derived peptides, and mimics thereof from various pathogens, in aqueous and membrane-like environments, using conventional and synchrotron radiation circular dichroism spectroscopy. A total of 13 peptides from the literature were studied, and 290 circular dichroism spectra were analysed. In addition, peptide structure predictions and vesicle aggregation assays were performed. Results: The results indicate a high level of similarity in the biophysical and folding properties of the peptides from either myelin proteins or proteins from pathogenic viruses or bacteria; essentially all of the studied peptides folded in the presence of lipid vesicles or under other membrane-mimicking conditions, which is a sign of membrane interaction. Many of the peptides presented remarkable similarities in their conformation in different environments. Conclusions: As most of the studied epitope segments in myelin proteins are associated with membrane-binding sites, our results support a view of molecular mimicry, involving lipid membrane interaction propensity and similar conformational properties, possibly playing a role in demyelinating disease. The results suggest mechanisms related to protein amphiphilicity and order-disorder transitions in the recognition of peptide epitopes in autoimmune demyelination