Differentiation capacity of BrdU label-retaining dental pulp cells during pulpal healing following allogenic transplantation in mice.

Our recent study has demonstrated the localization of putative dental pulp stem cells in the developing molar by chasing 5-bromo-2'-deoxyuridine (BrdU)-labeling. However, their differentiation capacity subsequent to the tooth transplantation remains to be elucidated. This study aims to clarify the differentiation capacity of BrdU label-retaining dental pulp cells and their relationship to cell proliferation and apoptosis during pulpal healing following allogenic transplantation in mice.

The expression of GM-CSF and osteopontin in immunocompetent cells precedes the odontoblast differentiation following allogenic tooth transplantation in mice.

Dental pulp elaborates both bone and dentin under pathological conditions such as tooth replantation/transplantation. This study aims to clarify the expression of granulocyte macrophage colony-stimulating factor (GM-CSF) and osteopontin (OPN) in the process of reparative dentin formation by allogenic tooth transplantation using in situ hybridization for OPN and immunohistochemistry for GM-CSF and OPN at both levels of light and electron microscopes. Following the extraction of the mouse molar, the roots and pulp floor were resected and immediately allografted into the sublingual region.

The relationship between the cusp pattern and plural stem cell compartments in Guinea pig cheek teeth by chasing BrdU-labeling.

Continuously growing rodent incisors have a special epithelial structure for maintaining adult stem cells that shows a bulbous epithelial protrusion at the apical end and is referred to as an "apical bud". Guinea pig cheek teeth (premolars and molars), also continuously growing teeth, have a complex crown shape consisting of plural cusps. The present study clarifies the existence of apical buds in guinea pig premolars/molars as it examines the relationship between the crown shape and the orientation of the apical buds by micro-computed tomography (micro-CT) and immunohistochemistry for 5-bromo-2'-deoxyuridine (BrdU).

Cell dynamics in the pulpal healing process following cavity preparation in rat molars.

Odontoblast-lineage cells acquire heat-shock protein (HSP)-25-immunoreactivity (IR) after they complete their cell division, suggesting that this protein acts as a switch between cell proliferation and differentiation during tooth development. However, there are few available data concerning the relationship between cell proliferation and differentiation following cavity preparation. The present study aims to clarify the expression of HSP-25 in the odontoblast-lineage cells with their proliferative activity after cavity preparation by immunocytochemistry for HSP-25 and cell proliferation assay using 5-bromo-2'-deoxyuridine (BrdU) labeling.

Rat wct mutation induces a hypo-mineralization form of amelogenesis imperfecta and cyst formation in molar teeth.

Our previous findings have demonstrated that the rat autosomal-recessive mutation, whitish chalk-like teeth (wct), induces enamel defects resembling those of human amelogenesis imperfecta (AI) in continuously growing incisor teeth. The present study clarifies the effect of the wct mutation on the morphogenesis and calcification of rat molar teeth. Formalin-fixed maxillae obtained from animals aged 4-30 days were examined by electron probe micro-analysis (EPMA) and by immunocytochemistry for amelogenin, ameloblastin, and enamelin.

RANK ligand expression in heat shock factor-2 deficient mouse bone marrow stromal/preosteoblast cells.

Heat Shock Proteins (HSP) are molecular chaperones activated upon cellular stress/stimuli. HSP gene expression is regulated by Heat Shock Factors (HSF). We have recently demonstrated a functional role for heat shock factor-2 (HSF-2) in fibroblast growth factor-2 (FGF-2)-induced RANK ligand (RANKL), a critical osteoclastogenic factor expression on stromal/preosteoblast cells.

Deficiency of insulin receptor substrate-1 impairs skeletal growth through early closure of epiphyseal cartilage.

Unlabelled: Morphological analyses in and around the epiphyseal cartilage of mice deficient in insulin receptor substrate-1 (IRS-1) showed IRS-1 signaling to be important for skeletal growth by preventing early closure of the epiphyseal cartilage and maintaining the subsequent bone turnover at the primary spongiosa.

Introduction: IRS-1 is an essential molecule for intracellular signaling by IGF-I and insulin, both of which are potent anabolic regulators of cartilage and bone metabolism. To clarify the role of IRS-1 signaling in the skeletal growth, morphological analyses were performed in and around the epiphyseal cartilage of mice deficient in IRS-1 (IRS-1(-/-)), whose limbs and trunk were 20-30% shorter than wildtype (WT) mice.

Possible role of immunocompetent cells and the expression of heat shock protein-25 in the process of pulpal regeneration after tooth injury in rat molars.

Recent studies have established that heat shock proteins (HSPs) potentially play a role in immunosurveillance. The purpose of the present study was to clarify the relationship between the chronological changes of immunocompetent cells and the expression of HSP-25 in the process of pulpal regeneration after tooth injury in rat molars by immunocytochemistry for HSP-25 and class II major histocompatibility complex (MHC) antigen. In untreated control teeth, intense HSP-25 immunoreactivity was found in the cell bodies of odontoblasts.

Ultrastructural and cytobiological studies on possible interactions between PTHrP-secreting tumor cells, stromal cells, and bone cells.

Parathyroid hormone-related peptide (PTHrP) induces pathological bone resorption in an endocrine manner, resulting in hypercalcemia of malignancy. However, the histopathological aspect of the action of PTHrP secreted by tumor cells on bone resorption has not well been documented. Therefore, we studied cell-cell interactions between bone cells, stromal cells, and PTHrP-secreting tumor cells (EC-GI-10) morphologically.