INTRODUCTION Oxygen is a critical parameter proposed to modulate the functions of chondrocytes ex-vivo as well as in damaged joints. This article investigates the effect of low (more physiological) oxygen percentage on the biosynthetic and catabolic activity of human articular chondrocytes (HAC) at different phases of in vitro culture. METHODS HAC expanded in monolayer were cultured in pellet...

Introduction: Articular cartilage possesses little intrinsic ability to heal after injury. When patient fail conservative management, current surgical treatments have included abrasion chondroplasty, osteochondral transplantation, and autologous chondrocytic implantation (ACI). Clinical outcome after treatment is generally good; however, good to excellent outcomes are not universal. In an attem...

The fetal and adult lung have a constant level of collagen synthesis that represents 4-5% of the total amino acids incorporated into lung protein. Prior studies have demonstrated that this collagen is not homogeneous but rather is composed of at least two collagen types, I and II, each localized to specific lung structures. Although it is known that explants of rabit lung parenchyma and blood v...

Organs of fish, amphibian, reptile, bird and mammals when stained by Sirius Red and studied with polarization microscopy present different colors in regions where collagens I, II and III have been described. Collagen type I presented a yellow, orange or red color while collagen type III appeared green. Collagen type II, present in cartilage and chondrosarcoma showed a variable color according t...

Chondrocytes isolated from bovine articular cartilage were plated at high density and grown in the presence or absence of ascorbate. Collagen and proteoglycans, the major matrix macromolecules synthesized by these cells, were isolated at times during the course of the culture period and characterized. In both control and ascorbate-treated cultures, type II collagen and cartilage proteoglycans a...

Background: Alteration in polymorphism of tissue collagens has been reported in association with some genetic and metabolic disorders. These alterations can be estimated quantitatively by measuring alpha-chain monomers derived from the polymeric form of collagens following treatment with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We studied the rate of placental colla...

OBJECTIVES Chondrocytic matrix metalloproteinases (MMPs) are believed to be important in osteoarthritic cartilage degradation. The cartilage lesion of osteoarthritis (OA) is focal and often progressive. During its development chondrocytes differentially up and down regulate production of mRNA for individual MMPs. This observation has potential implications for understanding the disease processe...

Rheumatoid arthritis is an autoimmune disease characterized by T-cell infiltration of the synovium of joints. Analysis of the phenotype and antigen specificity of the infiltrating cells may thus provide insight into the pathogenesis of rheumatoid arthritis. T cells were cloned with interleukin 2, a procedure that selects for in vivo-activated cells. All clones had the CD4 CDW29 phenotype. Their...

Differences in cartilage biomarkers have been noted in patients with anterior cruciate ligament tears, but little is known about any similar relationship with shoulder instability. This study evaluated the relationship between serum cartilage biomarkers and shoulder instability. The authors present a prospective cohort study of young athletes followed from 2006 to 2010. A nested case-control an...