Analysis of the essential oil from Gaillardia pulchella Foug. and its antioxidant activity.

The essential oil from Gaillardia pulchella Foug. flowers was obtained by hydrodistillation and its chemical composition was analyzed by gas chromatography-mass spectrometry (GC-MS). Twenty-eight compounds representing 92.63% of the essential oil were identified, of which the most prominent were n-Hexadecanoic acid (26.90%), Phytol (7.58%) and Cyclopropaneoctanoic acid, 2-[[2-[(2-ethylcyclopropyl) methyl] cyclopropyl] methyl]-, methyl ester (6.73%). Meanwhile, antioxidant activity of the essential oil was tested. The essential oil showed certain antioxidant activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH) with an EC50 of 70.95 µg/ml. This is the first report on the essential oil of this particular species. Its bioactivities warrant further studies.

[Comparison study on knee osteoarthritis in rabbits induced by different concentrations of papain].

OBJECTIVE: To compare the knee osteoarthritis (OA) models in rabbits by different concentrations of papain and provide data for exploring pathogenesis and treatments of this disease. METHODS: Sixty New Zealand white rabbits were randomly divided into four groups of 15 each and given injections into the right knee on days 1, 3 and 5 including intra-articular injections of 2%, 5% or 10% (w/v) papain and 0.03 mol/L L-cysteine at the dose of 0.1 ml/kg (experimental groups). The 0.9% NaCl (w/v) with a dose of 0.1 ml/kg were injected intra-articularly into the right knees of rabbits in the control group. The rabbits were sacrificed at 2, 4, 6 weeks respectively after the initiation of papain injection and these OA models were evaluated through recording the width of knee joint, performing the morphological observation and histological evaluation of articular cartilage and synovium. RESULTS: The degenerative changes were demonstrated in knee joints of rabbit in all experimental groups, such as thinner articular cartilage, fibrillation and destroyed cartilage matrix, and inflammation, proliferation, and degeneration of the synovial tissue. All these changes were much worse with increased concentration and prolonged observation time. CONCLUSION: Different severity of OA are established through intra-articular injections of 2%, 5% or 10% papain and 0.03 mol/L L-cysteine at the dose of 0.1 ml/kg. These models are of the characters of short period and a good reproducibility.

[The application of sodium hyaluronate in joint diseases].

OBJECTIVE: To review the physiological function of sodium hyaluronate in joints and its clinical applications. METHODS: Many literatures were reviewed and analysed on therapeutic mechanism and the application foreground of sodium hyaluronate. RESULTS: Extrinsic sodium hyaluronate plays an important role in improving synovial fluid and protecting cartilages as well as suppressing inflammation, so it is used in the treatment of joint diseases such as knee osteoarthritis, rheumatoid arthritis or temporomandibular osteoarthritis. CONCLUSION: Sodium hyaluronate possesses a good applied prospect in joint diseases.