Biomedical subjects

A Rass

Publications and source records attributed to A Rass.

3 recordsLinked to original sources

PubMed1995

Expression of the intermediate filament nestin during rodent tooth development.

The developing tooth represents a suitable model for understanding the molecular mechanisms involved in induction, morphogenesis and differentiation of organs. It is conceivable that the developmental changes could be reflected in the distribution of different cytoskeletal components and in this report we analyze the expression of the intermediate filament nestin during rodent tooth development at the protein and mRNA levels (by immuno light and electron microscopy, and by in situ hybridization). Nestin is expressed at all stages of tooth development, but the expression levels increase after birth in both ectodermal and ectomesenchymal derivatives. The shift in nestin distribution, from the proliferating dental lamina to the dental mesenchyme, indicates that nestin may be involved in inductive phenomena. At early stages of mineralization, nestin is seen within the apical parts of the presecretory ameloblasts. Nestin is also expressed in odontoblasts, both during odontogenesis and after tooth eruption. The increase in nestin expression from early to late developmental stages and sustained expression in a differentiated cell type contrasts with previously observed patterns of nestin expression during nerve and muscle development. This suggests that nestin could be used as a specific marker for the odontoblast.

Animals↗

PubMed1994

Distribution of C-CAM in developing oral tissues.

C-CAM is a cell surface glycoprotein that is involved in cell adhesion and may play a role in histogenesis and organogenesis. It is a member of the carcinoembryonic antigen (CEA) gene family, which is a subfamily of the immunoglobulin gene superfamily. We have analyzed the expression of C-CAM during normal and disturbed craniofacial development in the mouse by immunohistochemistry and in situ hybridization. Developmental disturbances were induced by retinoic acid (RA) treatment of pregnant mice. Normal and malformed fetuses were examined on days 14, 15, 16, 17 and 18 of gestation. The expression of C-CAM was detected first at day 16. With age, the signal became gradually stronger. C-CAM was detected in the epithelia of both ectodermal and mesodermal origin, including oral and respiratory epithelia, epithelia of the developing vessels, glands and their ducts. In the RA-treated fetuses, the expression of C-CAM was higher in the epithelium of the oral cavity than in that of the nasal cavity, with a distinct borderline between differentiating nasal and oral epithelium of the palatal shelves. However, the submucosal nasal glands and ducts showed higher expression than oral glands in both normal and RA-treated mice. The expression of C-CAM did not differ significantly between control and RA-treated animals. The presence of C-CAM in all proliferating craniofacial epithelia indicates that this molecule may play an important role in development.

Adenosine Triphosphatases↗

PubMedDate not supplied

Expression of E-cadherin during craniofacial development.

The cell adhesion molecule E-cadherin is assumed to play an important role in organogenesis and histogenesis. We have analyzed the presence of E-cadherin during normal and disturbed craniofacial development with respect to palate and tooth formation by immunohistochemistry using a rat monoclonal antibody (DECMA-1) and by in situ hybridization using an oligonucleotide probe. Cleft palate was induced by retinoic acid (RA) treatment of pregnant dams. Normal and RA-treated fetuses of gestational days 14-18 were examined. E-cadherin was present in epithelia of both ectodermal and endodermal origin, including developing teeth and epithelia of the palate as well as respiratory and oral epithelia. The expression level of E-cadherin increased with age and differentiation. In normal fetuses, at day 18, the expression was higher in the epithelia of the oral cavity than in the forming nasal cavity. The expression pattern of E-cadherin implies that this molecule has a role during normal development of the epithelia of the craniofacial complex.

Animals↗