Search results for "Endochondral ossification"
showing 7 items of 7 documents
Cranial bone histology of Metoposaurus krasiejowensis (Amphibia, Temnospondyli) from the Late Triassic of Poland
2016
In this study, 21 skull bones ofMetoposaurus krasiejowensisfrom the Late Triassic of Poland were investigated histologically. Dermal bones show a diploë structure, with an ornamented external surface. The ridges consist of mostly well vascularized parallel-fibered bone; the valleys are built of an avascular layer of lamellar bone. The thick middle region consists of cancellous bone, with varying porosity. The thin and less vascularized internal cortex consists of parallel-fibered bone. The numerous Sharpey’s fibers and ISF are present in all bones. The cyclicity of growth is manifested as an alternation of thick, avascular annuli and high vascularized zones as well as a sequence of resting …
Expression profiling of human fetal growth plate cartilage by EST sequencing.
2005
The differentiation of mesenchymal stem cells into hypertrophic chondrocytes is an integral and multistep process important in pattern formation, endochondral ossification, and postnatal growth of the skeleton. In recent years, novel genes involved in these processes have been identified, but still only little is known about the large-scale gene expression profile during skeletal development. We initiated an expressed sequence tag (EST) project aiming at the identification of genes and pathways involved in this complex process. Candidate genes are expected to be of value for diagnosis and treatment of monogenic and multigenic heritable disorders of the skeleton. Here, we describe the sequen…
Heterogeneity of osteogenesis imperfecta. Biochemical and morphological findings in a case of type III according to Sillence.
1986
A male infant with pale-blue sclerae, who died at the age of 6 weeks through the aspiration of food, presented multiple fractures and deformation of the long tubular bones. The clinical and radiological findings and the course indicated osteogenesis imperfecta, type III, according to Sillence's classification. The family history was unremarkable. Light and electron microscopic studies of iliac crest bone obtained postmortem, showed an abrupt interruption of endochondral ossification, with an active periosteal ossification. In the region of the fractures, a mixed desmochondral callus was seen. The endoplasmic reticulum of the osteoblasts was markedly dilated, the mitochondria were swollen. T…
Histological characteristics of the vertebral intercentra of Metoposaurus diagnosticus (Temnospondyli) from the Upper Triassic of Krasiejów (Upper Si…
2012
ABSTRACTOsteohistological characteristics of the large temnospondyl amphibian Metoposaurus diagnosticus from the Upper Triassic of Poland (Krasiejów locality) were determined using vertebral intercentra thin-sections from different regions and growth stages. The intercentra showed a trabecular structure in both the endochondral and periosteal domains. Endochondral ossification developed first, and the primary bone occurs near the periphery with a higher degree of remodelling in the centre. Periosteal bone deposition begins later; first on the ventral side, continuing laterally and finally onto the dorsal side. Periosteal growth rate was initially very rapid, and then subsequently decreased …
The microstructural variability of the intercentra among temnospondyl amphibians
2014
The histology of the vertebral centrum of the morphologically diverse Temnospondyli is poorly known. In this study, the variability of the histological framework of various taxa from several Permian and Triassic localities was investigated for the first time. Twelve intercentra, forming the anterior part of the diplospondylous centra of temnospondyls, were examined histologically. The intercentra of all studied taxa share a highly vascularized cortex on the ventro-lateral side and primary and secondary trabecular, endochondral bone on the dorsal side. A high variability is present, among others, within the arrangement of the vascular cavities, the density of the trabeculae and the distribut…
Zebrafish Fins as a Model System for Skeletal Human Studies
2007
Recent studies on the morphogenesis of the fins ofDanio rerio(zebrafish) during development and regeneration suggest that a number of inductive signals involved in the process are similar to some of those that affect bone and cartilage differentiation in mammals and humans. Akimenko et al. (2002) has shown that bone morphogenetic protein-2b (BMP2b) is involved in the induction of dermal bone differentiation during fin regeneration. Many other groups have also shown that molecules from the transforming growth factor-beta superfamily (TGFβ), including BMP2, are effective in promoting chondrogenesis and osteogenesisin vivoin higher vertebrates, including humans. In the present study, we review…
Osteoprotegerin (OPG) and RANKL expression and distribution in developing human craniomandibular joint.
2005
Abstract During embryogenesis the bone tissue of craniomandibular joint (CMJ) is formed through two pathways: intramembranous ossification and endochondral ossification. The development process is under the control of regulatory factors.The osteoprotegerin (OPG) and the receptor activator of nuclear factor (NF)-κB ligand are key regulators of osteoclastogenesis. The aim of this study is the localization of OPG and RANKL mRNA and protein in the foetal CMJ by immunohistochemistry (IHC) and in situ hybridization (ISH). The main results were: OPG and RANKL mRNA and protein were co-localized in the same cell types; OPG and RANKL were specially immunolocated in osteogenic cells; immunolabeling wa…