Search results for "Articular Cartilage"
showing 10 items of 50 documents
Biomaterial-based approaches and adult stem cells
2009
Collecting evidence for a stem cell hypothesis in HCC.
2010
Ever since Ernest McCulloch and James E Till defined essential stem cell properties, the field of stem cell biology has attracted increasing interest.1 Manipulating embryonic stem cells has resulted in advanced genetic technologies such as knock-out and transgenic animals, providing valuable models to study genetic influence on a wide variety of diseases.2 The success in manipulating stem cells and the ability to differentiate them into diverse tissues brought with them countless concepts of utilising stem cells in medicine. The idea of perpetually dividing pluripotent cells, capable of differentiating into nearly every possible cell or tissue type, seems like an inexhaustible resource for …
Volumetric changes of articular cartilage during stress relaxation in unconfined compression
2000
The time-dependent lateral expansion and load relaxation of cartilage cylinders subjected to unconfined compression were simultaneously recorded. These measurements were used to (1) test the assumption of incompressibility for articular cartilage, (2) measure the Poisson's ratio of articular cartilage in compression and (3) investigate the relationship between stress relaxation and volumetric change. Mechanical tests were performed on fetal, calf, and adult humeral head articular cartilage. The instantaneous Poisson's ratio of adult cartilage was 0.49+/-0.08 (mean+S.D.), thus confirming the assumption of incompressibility for this tissue. The instantaneous Poisson's ratio was significantly …
Genetic abrogation of the fibronectin-α5β1 integrin interaction in articular cartilage aggravates osteoarthritis in mice.
2018
The balance between synthesis and degradation of the cartilage extracellular matrix is severely altered in osteoarthritis, where degradation predominates. One reason for this imbalance is believed to be due to the ligation of the α5β1 integrin, the classic fibronectin (FN) receptor, with soluble FN fragments instead of insoluble FN fibrils, which induces matrix metalloproteinase (MMP) expression. Our objective was to determine whether the lack of α5β1-FN binding influences cartilage morphogenesis in vivo and whether non-ligated α5β1 protects or aggravates the course of osteoarthritis in mice. We engineered mice (Col2a-Cre;Fn1RGE/fl), whose chondrocytes express an α5β1 binding-deficient FN, …
Current knowledge of pituitary adenylate cyclase activating polypeptide (PACAP) in articular cartilage
2020
Pituitary adenylate cyclase activating polypeptide (PACAP) is an evolutionally well conserved neuropeptide, mainly expressed by neuronal and peripheral cells. It proves to be an interesting object of study both for its trophic functions during the development of several tissues and for its protective effects against oxidative stress, hypoxia, inflammation and apoptosis in different degenerative diseases. This brief review summarises the recent findings concerning the role of PACAP in the articular cartilage. PACAP and its receptors are expressed during chondrogenesis and are shown to activate the pathways involved in regulating cartilage development. Moreover, this neuropeptide proves to be…
Expression of Gelatinases (MMP-2, MMP-9) in human articular cartilage
2013
Osteoarthritis (OA) is a chronic degenerative joint disorder characterized by destruction of the articular cartilage, subchondral bone alterations and synovitis. Matrix metalloproteinases (MMPs) are expressed in joint tissues of patients with osteoarthritis (OA). The objective of this study was to define the steady state levels of two different MMPs to provide more insight into the role of MMPs in cartilage destruction in OA. We investigated the expression of gelatinases through immunohistochemistry Our results show that high levels of MMP-2 and MMP-9 are present in OA and suggest that once these MMPs are fully activated they may contribute to the cartilage destruction in OA.
Nondestructive fluorescence-based quantification of threose-induced collagen cross-linking in bovine articular cartilage.
2012
Extensive collagen cross-linking affects the mechanical competence of articular cartilage: it can make the cartilage stiffer and more brittle. The concentrations of the best known cross-links, pyridinoline and pentosidine, can be accurately determined by destructive high-performance liquid chromatography (HPLC). We explore a nondestructive evaluation of cross-linking by using the intrinsic fluorescence of the intact cartilage. Articular cartilage samples from bovine knee joints were incubated in threose solution for 40 and 100 h to increase the collagen cross-linking. Control samples without threose were also prepared. Excitation-emission matrices at wavelengths of 220 to 950 nm were acquir…
The ultrastructure of articular cartilage of the chicken's knee joint
1993
The articular cartilage and synovial membrane of immature and mature chicken knee joints were studied by light, scanning and transmission microscopy. The findings differed from human articular cartilage and we conclude that the chicken knee joint is not suitable as a model for human joint degeneration.
Wharton’s Jelly Mesenchymal Stem Cells for the Treatment of Type 1 Diabetes
2014
Type 1 diabetes is an autoimmune disease caused by the destruction of endocrine pancreas β cells by T lymphocytes, for which genetic and environmental risk factors have been proposed. Patients require daily infusions of recombinant insulin to overcome the reduced production by their own cells, but there is an increasing demand for a permanent and efficient supplementation which could better modulate the need for the hormone during the normal activities. For this reason, transplant-based therapeutic models have been proposed such as whole organ transplantation and Langerhans islets transplantation. These techniques are limited by many factors such as the lack of donors, the risks linked to t…
The expression of CD68 in human umbilical cord mesenchymal stem cells: new evidences of presence in non-myeloid cell types.
2009
Since their first identification in bone marrow [2],MSC have attracted much attention for thei r potential todifferentiate towards several mature tissues. The efforts ofthe researchers aimed in finding new tissues, whichshould provide adequate cell numbers for regenerativemedicine applications (and between them, extraembryonicsources as umbilical cord and amniotic membrane, arebeing viewed with extreme interest).