Expanding the Scholarship on Leadership Training in Dental Education

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153680/1/jddj002203372014786tb05733x.pd

Dentists’ Leadership‐Related Educational Experiences, Attitudes, and Past and Current Behavior

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153576/1/jddj002203372014786tb05741x.pd

Where Is Leadership Training Being Taught in U.S. Dental Schools?

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153740/1/jddj002203372012766tb05305x.pd

Perceptions of Business Skill Development by Graduates of the University of Michigan Dental School

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153743/1/jddj002203372011754tb05074x.pd

The Bone Marrow Endosteal Niche: How Far from the Surface?

aaHematopoietic stem cells (HSC) self‐renewal takes place in the same microenvironment in which massive hematopoietic progenitor proliferation, commitment, and differentiation will occur. This is only made possible if the bone marrow microenvironment comprises different specific niches, composed by different stromal cells that work in harmony to regulate all the steps of the hematopoiesis cascade. Histological and functional assays indicated that HSC and multipotent progenitors preferentially colonize the endosteal and subendosteal regions, in close association with the bone surface. Conversely, committed progenitors and differentiated cells are distributed in the central and perisinusoidal regions, respectively. Over the last decade, many investigative teams sought to define which cell types regulate the HSC niche, how they are organized, and to what extent they interface with each other. System dynamics requires different stromal cells to operate distinct functions over similar HSC pools rather than a single stromal cell type controlling everything. Therefore, our focus herein is to depict the players in the endosteal and subendosteal regions, named the endosteal niche, a necessary step to better understand the interactions of the HSC within the niche and to identify potential targets to manipulate and/or modulate normal and malignant HSC behavior. J. Cell. Biochem. 116: 6–11, 2015. © 2014 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109640/1/jcb24952.pd

Ablation of Proliferating Marrow with 5‐Fluorouracil Allows Partial Purification of Mesenchymal Stem Cells

The ability to identify and maintain mesenchymal stem cells in vitro is a prerequisite for the ex vivo expansion of cells capable of effecting mesenchymal tissue regeneration. The aim of this investigation was to develop an assay to enrich and ultimately purify mesenchymal stem cells. To enrich the population of mesenchymal stem cell‐like cells, rats or mice were administered 5‐fluorouracil (5‐FU) in vivo. Limiting dilution analysis demonstrated that 5‐FU‐treated bone marrow had the potential to form colony‐forming units‐fibroblastic (CFU‐F) at a 10‐fold or sixfold enrichment compared to normal bone marrow in rats or mice, respectively. In vivo and in vitro differentiation assays supported the enrichment and purification effects. In vitro, bone marrow cultures from 5‐FU‐treated bone marrow demonstrated lineage‐specific gene expression in lineage‐specific medium conditions in contrast to the multilineage gene expression of control bone marrow cultures. In vivo implantation of 5‐FU‐treated cells that were not expanded in culture generated ossicles containing an intact bone cortex and mature hematopoietic components, whereas non‐5‐FU‐treated bone marrow only formed fibrous tissues. Our results demonstrate that enrichment of a quiescent cell population in the bone marrow by in vivo treatment of 5‐FU spares those undifferentiated mesenchymal stem cells and influences the differentiation of bone marrow stromal cells in vitro and in vivo. This prospective identification of a population of mesenchymal cells from the marrow that maintain their multilineage potential should lead to more focused studies on the characterization of a true mesenchymal stem cell.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90309/1/241573_ftp.pd

Effects of interleukin-1 β and tumor necrosis factor-α on osteoblastic expression of osteocalcin and mineralized extracellular matrix in vitro

Osteoblasts play a pivotal role during the bioresponse of bone to agents that stimulate bone resorption and/or inhibit bone formation including hormones, polypeptide growth factors, and cytokines. We examined the cytokines interleukin-1-beta (IL-1 β ) and tumor necrosis factor-alpha (TNF- α ) for their effects on osteoblastic proliferation and development and expression of alkaline phosphatase and the osteoblast-specific protein osteocalcin in a mineralizing environment. Primary rat osteoblast-like cells (ROB) and osteoblastic cell lines derived from rat (ROS 17/2.8) and human (MG-63) osteosarcomas were studied. IL-1 β and TNF- α were chosen because of their critical importance during the host response to local inflammatory stimuli. Qualitatively similar two- to threefold inhibition of osteocalcin synthesis by IL-1β and TNF- α were observed in all three postconfluent bone-forming model systems. Because of the readily measurable concentrations of osteocalcin produced in our culture protocol, it was not necessary to enhance osteoblastic synthesis of osteocalcin by supplementation with 1,25(OH) 2 -vitamin D 3 , a treatment which exerts pleiotropic effects on osteoblasts. Under the constraints of our protocol, where alkaline phosphatase and mineralization were already elevated at the 14-day onset of treatment, neither of these phenotypic properties was sensitive to a three-day cytokine exposure. Differences were noted in proliferation, where only TNF- α stimulated DNA synthesis in ROB cells, while both cytokines stimulated MG-63 cells. IL-1 β and TNF- α failed to alter ROS 17/2.8 DNA synthesis except at the highest doses (25 pM IL-1β and l nM TNF- α ) where inhibition was observed. These results further support the view that cytokine-mediated osteoblastic regulation can be relatively selective.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44508/1/10753_2004_Article_BF00919342.pd

Developing the Next Generation of Leaders in Oral Health

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153770/1/jddj0022033720137711tb05627x.pd