Search results for "Cell biology"
showing 10 items of 8732 documents
The Tongue, Mandible, Hyoid System.
2017
The craniocervical-mandibular system works in harmony and allows different functional tasks as the postural control of the cervical region. This system is formed by the temporomandibular joint, the masticatory muscles and ligaments connecting the temporomandibular joint and the cervical region. It has been seen to affect human posture, and many disorders of the temporomandibular joints may affect this functional arrangement. Notwithstanding this system considered as a functional arrangement, may offer various clinical explanations, it does not hold anatomical connections with the posterior region of the cranium, thus it should not be refered to as a craniocervical arrangement. For this reas…
Mouse CSB protein is important for gene expression in the presence of a single-strand break in the non-transcribed DNA strand.
2010
CSB protein is required for strand-specific repair of bulky DNA lesions in transcribed genes and mediates transcription recovery after exposure to DNA-damaging agents. We enzymatically generated DNA single-strand breaks (SSBs) with 3'-OH and 5'-phosphate termini in defined positions of a plasmid-borne gene and measured their effect on transcription in cell lines with different statuses of the Csb gene. A single SSB in the transcribed region of the gene caused significant decrease of gene expression. In all tested cell lines of mouse and human origin, a SSB in the transcribed DNA strand was less harmful for gene expression than a SSB situated in the opposing DNA strand. CSB deficiency exhibi…
Clonal heterogeneity of the growth and invasive response of a human breast carcinoma cell line to parathyroid hormone-related peptide fragments
1997
It has been previously reported that 8701-BC cells, derived from a primary carcinoma of the breast, constitutively express parathyroid hormone (PTH)-related peptide (PTHrP) and PTH/PTHrP receptor (PTH/PTHrP-R) genes, that N-terminal, mid-regional and C-terminal immunoreactive PTHrP can be found in cell conditioned medium and, furthermore, that exogenously added PTHrP (1-34), (67-86) and, to a minor extent, (107-139) are anti-mitogenic but promote Matrigel invasion by this cell line. It has also been reported that PTHrP gene expression is selectively switched on in those 8701-BC clonal lines endowed with a higher proliferation rate and invasive ability in vitro. Here we have first examined t…
Physiological incongruity of the humero-ulnar joint: a functional principle of optimized stress distribution acting upon articulating surfaces?
1993
Investigations into the distribution of subchondral bone density in the human elbow have suggested that the geometry of the trochlear notch deviates from a perfect fit with the trochlea, and that the load is transmitted ventrally and dorsally rather than through the centre of the humero-ulnar joint. We therefore decided to make a quantitative assessment of the degree of incongruity between the two components in 15 human specimens (age distribution 60 to 93 years) with different types of joint surface. Polyether casts of the joint cavity were prepared under loads of 10, 40, 160 and 640 N. The thickness of the casts was then measured at 50 predetermined points, and an area distribution of the…
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…
Silicate modulates the cross-talk between osteoblasts (SaOS-2) and osteoclasts (RAW 264.7 cells): inhibition of osteoclast growth and differentiation
2012
It has been shown that inorganic monomeric and polymeric silica/silicate, in the presence of the biomineralization cocktail, increases the expression of osteoprotegerin (OPG) in osteogenic SaOS-2 sarcoma cells in vitro. In contrast, silicate does not affect the steady-state gene expression level of the osteoclastogenic ligand receptor activator of NF-κB ligand (RANKL). In turn it can be expected that the concentration ratio of the mediators OPG/RANKL increases in the presence of silicate. In addition, silicate enhances the growth potential of SaOS-2 cells in vitro, while it causes no effect on RAW 264.7 cells within a concentration range of 10-100 µM. Applying a co-cultivation assay system,…
Osteoprotegerin: multiple partners for multiple functions.
2013
Osteoprotegerin (OPG) is an essential secreted protein in bone turnover due to its role as a decoy receptor for the Receptor Activator of Nuclear Factor-kB ligand (RANKL) in the osteoclasts, thus inhibiting their differentiation. However, there are additional ligands of OPG that confer various biological functions. OPG can promote cell survival, cell proliferation and facilitates migration by binding TNF-related apoptosis inducing ligand (TRAIL), glycosaminoglycans or proteoglycans. A large number of in vitro, pre-clinical and clinical studies provide evidences of OPG involvement in vascular, bone, immune and tumor biology. This review describes an overview of the different OPG ligands regu…
Osteogenic differentiation of periodontal fibroblasts is dependent on the strength of mechanical strain
2012
Abstract Objective During orthodontic therapy the correct strength of mechanical strain plays a key role for bone remodelling during tooth movement. Aim of this study was to investigate the osteogenic differentiation of human periodontal ligament fibroblasts (HPdLF) depending on the applied strength of mechanical strain compared to osteoblasts (HOB). Design HPdLF and HOB were loaded with different strengths (1%, 5% and 10%) of static mechanical strain (SMS) for 12 h in vitro. Viability was verified by MTT and apoptosis by TUNEL assay. Gene expression of cyclin D1, collagen type-1 (COL-I), alkaline phosphatase (ALP), osteocalcin, osteoprotegerin (OPG) and receptor activator of the NF-κB liga…
Dystroglycan regulates structure, proliferation and differentiation of neuroepithelial cells in the developing vertebrate CNS.
2007
AbstractIn the developing CNS α- and β-dystroglycan are highly concentrated in the endfeet of radial neuroepithelial cells at the contact site to the basal lamina. We show that injection of anti-dystroglycan Fab fragments, knockdown of dystroglycan using RNAi, and overexpression of a dominant-negative dystroglycan protein by microelectroporation in neuroepithelial cells of the chick retina and optic tectum in vivo leads to the loss of their radial morphology, to hyperproliferation, to an increased number of postmitotic neurons, and to an altered distribution of several basally concentrated proteins. Moreover, these treatments also altered the oriented growth of axons from retinal ganglion c…
Bioengineered in vitro 3D model of myotonic dystrophy type 1 human skeletal muscle
2021
Abstract Myotonic dystrophy type 1 (DM1) is the most common hereditary myopathy in the adult population. The disease is characterized by progressive skeletal muscle degeneration that produces severe disability. At present, there is still no effective treatment for DM1 patients, but the breakthroughs in understanding the molecular pathogenic mechanisms in DM1 have allowed the testing of new therapeutic strategies. Animal models and in vitro two-dimensional cell cultures have been essential for these advances. However, serious concerns exist regarding how faithfully these models reproduce the biological complexity of the disease. Biofabrication tools can be applied to engineer human three-dim…