| 1. |
- Arvidson, Nils Gunnar, et al.
(författare)
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Circadian rhytm of serum interleukin-6 in rheumatoid arthritis
- 1994
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Ingår i: Annals of the Rheumatic Diseases. - 0003-4967 .- 1468-2060. ; 53:8, s. 521-4
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES--To test the hypothesis of a diurnal variation in circulating levels of interleukin-6 (IL-6) and/or tumour necrosis factor-alpha (TNF-alpha) in rheumatoid arthritis and other inflammatory connective tissue diseases. METHODS--Serum levels of IL-6 and TNF-alpha were measured at three hour intervals from 7:30 to 22:30 in 48 patients with different rheumatic diseases as well as ten healthy controls. In four of the patients with rheumatoid arthritis, serum IL-6 levels were measured before and after one week of treatment with prednisolone 15-20 mg daily. RESULTS--IL-6 and TNF-alpha could not be detected in serum from healthy controls. However, serum IL-6 levels were substantially increased in patients with rheumatoid arthritis. Furthermore, patients with rheumatoid arthritis showed a statistically significant circadian variation in levels of IL-6. Peak values appeared in the morning and low values in the afternoon and evening. In contrast, levels were low and stable in other connective tissue diseases. Levels of TNF-alpha were low in patients with rheumatoid arthritis and high in patients with other connective tissue diseases, but without circadian rhythm. After treatment with prednisolone, levels of serum IL-6 decreased significantly, but the circadian rhythm remained. CONCLUSIONS--The circadian rhythm of circulating IL-6 might correspond to the circadian rhythm of symptoms in rheumatoid arthritis. The diurnal variation of IL-6, and possibly other cytokines, might explain the conflicting results previously reported on the inter-relationship between circulating IL-6 levels and disease activity in rheumatoid arthritis.
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| 2. |
- Lammi, Mikko, 1961-, et al.
(författare)
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Adaptation of canine femoral head articular cartilage to long distance running exercise in young beagles.
- 1993
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Ingår i: Annals of the Rheumatic Diseases. - : British Medical Journal. - 0003-4967 .- 1468-2060. ; 52:5, s. 369-377
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To study the effects of long term (one year), long distance (up to 40 km/day) running on the metabolism of articular cartilage the biosynthesis of proteoglycans was examined by in vitro labelling of anterior (weight bearing) and posterior (less weight bearing) areas of the femoral head from young beagles.METHODS: Total sulphate incorporation rates were determined and distribution of the incorporated sulphate was localised by quantitative autoradiography. Concentration and extractability of the proteoglycans were determined, and proteoglycan structures were investigated by gel filtration chromatography, agarose gel electrophoresis, and chemical determinations.RESULTS: In the less weight bearing area the amount of extractable proteoglycans was decreased (p < or = 0.02), simultaneously with an increased concentration of residual glycosaminoglycans in the tissue after 4 M GuCl extraction (p < or = 0.05). In control animals proteoglycan synthesis was most active in the deep zone of the cartilage, whereas exercise increased synthesis in the intermediate zone. There was a tendency to a lower keratan: chondroitin sulphate ratio in the running dogs. No macroscopical or microscopical signs of articular degeneration or injury were visible in any of the animals.CONCLUSION: The articular cartilage of the femoral head showed a great capacity to adapt to the increased mechanical loading. The reduced proteoglycan extractability in the less weight bearing area changed it similar to the weight bearing area, suggesting that the low extractability of proteoglycans reflects the long term loading history of articular cartilage. The congruency of the femoral head with acetabulum seems to protect the cartilage from the untoward alterations that occur in the femoral condyles subjected to a similar running programme.
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| 3. |
- Månsson, Bengt, et al.
(författare)
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Cytidine deaminase activity in synovial fluid of patients with rheumatoid arthritis: relation to lactoferrin, acidosis, and cartilage proteoglycan release
- 1990
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Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 49:8, s. 594-597
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Tidskriftsartikel (refereegranskat)abstract
- It is claimed that cytidine deaminase activity reflects local granulocyte turnover or activity in the synovial fluid of patients with rheumatoid arthritis, but cytidine deaminase is not a granulocyte specific enzyme. Lactoferrin is a granulocyte specific protein that is released from the secondary granulae during activation. We measured cytidine deaminase activity and lactoferrin concentrations in 33 rheumatic synovial fluid samples. Cytidine deaminase activity and lactoferrin concentrations correlated closely, indicating that both analyses reflect similar events in the joint-that is, result in their release from granulocytes. Cytidine deaminase activity and granulocyte concentrations correlated less closely, suggesting that there are additional factors besides the cell number which contribute to this release. Joint acidosis may be one such factor, as pH and cytidine deaminase activity correlated inversely. There was no association with synovial fluid proteoglycan concentrations, a marker of cartilage degradation.
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| 4. |
- Nilsson, B, et al.
(författare)
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Reconstitution of the alternative pathway of complement by plasma infusions given to a patient with an SLE-like syndrome associated with a hereditary C3 dysfunction.
- 1994
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Ingår i: Annals of the Rheumatic Diseases. - 0003-4967 .- 1468-2060. ; 53:10, s. 691-694
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To reconstitute a dysfunctional form of complement factor C3 in a patient with a systemic lupus erythematosus (SLE)-like syndrome.METHODS: The propositus was treated with plasma infusions during five sessions over a period of eight months.RESULTS: The alternative pathway was reconstituted to normal levels for approximately two to three days after each infusion. C3 fragments were incorporated into previously detected deposits of IgG and IgM at the dermal-epidermal junction and the immune complex levels gradually decreased during the whole treatment period.CONCLUSION: The reconstitution appears to result in the solubilisation of tissue immune complexes and a subsequent transportation to the fixed macrophage system.
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| 5. |
- Parkkinen, Jyrki, et al.
(författare)
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Altered Golgi apparatus in hydrostatically loaded articular cartilage chondrocytes.
- 1993
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Ingår i: Annals of the Rheumatic Diseases. - : British Medical Journal. - 0003-4967 .- 1468-2060. ; 52:3, s. 192-198
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Articular cartilage proteoglycan content is controlled by joint loading. This study aimed to elucidate the role of hydrostatic pressure in this regulation.METHODS: Primary cultures of chondrocytes from bovine articular cartilage, grown on coverslips, were subjected to 5, 15, or 30 MPa hydrostatic pressure, applied continuously or cyclically at 0.125 or 0.05 Hz. The Golgi apparatus was visualised either by a fluorochrome coupled wheat germ agglutinin or by transmission electron microscopy. Proteoglycan synthesis was studied by the incorporation of sulphur-35 labelled sulphate.RESULTS: After 30 MPa continuous hydrostatic pressure, the Golgi apparatus was observed in a compact form with a concomitant decrease in proteoglycan synthesis. The normal stacked appearance of the Golgi apparatus was no more visible in the electron microscopy preparation of the pressurised chondrocytes. This effect was reversible and was also noticed after 15 MPa continuous load, though to a minor extent. Cyclic pressures (5-30 MPa) caused no apparent change in the Golgi apparatus. The shape of some cells changed to a more retracted form after 30 MPa continuous pressure. Nocodazole, which causes disassembly of the microtubules, blocked the compacting influence of pressurisation on the Golgi apparatus, and reduced proteoglycan synthesis to about half of the control level.CONCLUSIONS: The packing of the Golgi apparatus is dependent on microtubules and may contribute to the inhibition of proteoglycan synthesis observed in articular cartilage subjected to high hydrostatic pressure.
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| 6. |
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| 7. |
- Dahlberg, L., et al.
(författare)
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Cartilage metabolism in the injured and uninjured knee of the same patient
- 1994
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Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 0003-4967. ; 53:12, s. 823-827
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Tidskriftsartikel (refereegranskat)abstract
- Objective-To examine if unilateral knee injury affects the synovial fluid concentrations of aggrecan fragments, cartilage oligomeric matrix protein (COMP) fragments, stromelysin-l, and tissue inhibitor of metalloproteinases-l (TIMP-1) in the contralateral uninjured knee. Methods-Synovial fluids from the injured and uninjured knees were obtained at different times in a group of patients after unilateral knee trauma. Serum samples were obtained on the same occasion. Concentrations of aggrecan fragments were determined by precipitation with Alcian Blue; those of COMP fragments, stromelysin-l, and TIMP-1 were measured by immunoassay. Concentrations were compared with those in a reference group of 10 healthy volunteers. Results-Immediately after knee injury, concentrations of aggrecan fragments, COMP fragments, stromelysin-l and TIMP-1 were increased in the synovial fluid of the injured knee. However, concentrations of aggrecan and COMP fragments, and stromelysin-l increased also in the contralateral uninjured knee immediately after injury, but less than in the injured knee. Subsequently, the concentrations ofall markers decreased in the synovial fluid of the injured knee, but remained unchanged in the uninjured knee. The concentration of aggrecan fragments in the injured knee decreased to less than that in the uninjured knee in the chronic phase. Serum concentrations of COMP were much smaller than those in synovial fluid. Conclusions-The increased concentrations of aggrecan and COMP fragments and stromelysin-1 in the joint fluid of the contralateral, uninjured knee following unilateral knee injury, compared with concentrations in healthy reference knees, suggest changes in joint cartilage metabolism in both knees following unilateral knee injury. The mechanisms for these changes are unclear. The low serum concentration of COMP makes it less likely that there is any significant 'exchange' of molecular markers between the knees. A further consequence of these findings is that the contralateral knee cannot be recommended as the only control joint in studies of matrix metabolism in patients with unilateral knee injury.
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| 8. |
- Lohmander, L. S., et al.
(författare)
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Release of cartilage oligomeric matrix protein (COMP) into joint fluid after knee injury and in osteoarthritis
- 1994
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Ingår i: Annals of the Rheumatic Diseases. - 0003-4967. ; 53:1, s. 8-13
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Tidskriftsartikel (refereegranskat)abstract
- Objective - The release of fragments of cartilage oligomeric matrix protein (COMP) and aggrecan into knee joint fluid and serum after joint injury and in post-traumatic and primary osteoarthritis was monitored in a cross-sectional study. Methods - Samples of joint fluid and serum were obtained from healthy volunteers and from patients with arthroscopically verified injury to anterior cruciate ligament and or meniscus of the knee at different times after injury and with different degrees of post-traumatic osteoarthritis. Samples were also obtained from patients with primary osteoarthritis. Fragments of COMP were quantified in joint fluid and in serum by enzyme-linked immunoassay. Fragments of aggrecan were quantified in joint fluid by enzyme-linked immunoassay. Results - Concentrations of COMP and aggrecan fragments in joint fluid in the study groups were increased over the reference levels of 47 (range 10-109) and 34 (range 6-59) μg/mL, respectively, in the volunteers with healthy knees. The ratios (w/w) of aggrecan to COMP fragments in joint fluid were also increased in all study groups over that in the reference group. Average concentration of COMP in joint fluid were high shortly after injury and decreased with time but remained increased over reference levels for many years. Joint fluid COMP concentrations were also increased in early stage post-traumatic and primary osteoarthritis, but not in advanced osteoarthritis. Conclusion - Increased amounts of aggrecan and COMP fragments are released into joint fluid after joint injury and in early stage osteoarthritis. The ratios of aggrecan to COMP in joint fluid vary with time after injury and with osteoarthritis disease stage. Although both molecules are sensitive to the agents active in matrix breakdown in joint disease, differences may thus exist in the release mechanisms and attempted repair. The concentrations of the individual markers in body fluids and their ratios may serve to monitor treatment efficacy, disease progression and repair in osteoarthritis and other joint diseases.
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