Initiation of degenerative joint damage by experimental bleeding combined with loading of the joint: a possible mechanism of hemophilic arthropathy

OBJECTIVE

To investigate the effect of a limited number of experimental joint bleedings, combined with loading of the affected joint, on the development of progressive degenerative joint damage.

METHODS

The right knee of 8 mature beagle dogs was injected with freshly collected autologous blood 3 times per week for 4 weeks, to mimic a limited number of joint hemorrhages occurring over a short period. To ensure loading of the experimental joint, the contralateral control knee of the animals was fixed to the trunk 4 hours per day, 3 days per week. Ten weeks after the last injection, cartilage tissue and synovium were collected from both knees to analyze features of joint degeneration. Cartilage was prepared for analysis of proteoglycan turnover (synthesis, retention, release, and content) and histologic features. Synovium was prepared for histologic analysis.

RESULTS

The rate of proteoglycan synthesis was significantly increased, characteristic of degenerative cartilage damage as seen in osteoarthritis. Release of newly formed proteoglycans (as a measure of retention) and total loss of proteoglycans from the cartilage matrix were increased. Cartilage matrix integrity was adversely altered, as shown by histologic damage. Histologic analysis also revealed signs of synovial inflammation. These effects were not observed 10 weeks after the experimental bleedings in joints that did not undergo forced loading.

CONCLUSION

Experimental joint bleedings when combined with loading of the affected joint resulted in features of progressive degenerative joint damage, whereas similar joint hemorrhages without joint loading did not. This might reflect a possible mechanism of joint damage in hemophilia.

Accumulation of advanced glycation end products as a molecular mechanism for aging as a risk factor in osteoarthritis

OBJECTIVE

Osteoarthritis (OA) is one of the most prevalent and disabling chronic conditions affecting the elderly. Its etiology is largely unknown, but age is the most prominent risk factor. The current study was designed to test whether accumulation of advanced glycation end products (AGEs), which are known to adversely affect cartilage turnover and mechanical properties, provides a molecular mechanism by which aging contributes to the development of OA.

METHODS

The hypothesis that elevated AGE levels predispose to the development of OA was tested in the canine anterior cruciate ligament transection (ACLT) model of experimental OA. Cartilage AGE levels were enhanced in young dogs by intraarticular injections of ribose. This mimics the accumulation of AGEs without the interference of other age-related changes. The severity of OA was then assessed 7 weeks after ACLT surgery in dogs with normal versus enhanced AGE levels.

RESULTS

Intraarticular injections of ribose enhanced cartilage AGE levels approximately 5-fold, which is similar to the normal increase that is observed in old dogs. ACLT surgery resulted in more-pronounced OA in dogs with enhanced AGE levels. This was observed as increased collagen damage and enhanced release of proteoglycans. The attempt to repair the matrix damage was impaired; proteoglycan synthesis and retention were decreased at enhanced AGE levels. Mankin grading of histology sections also revealed more-severe OA in animals with enhanced AGE levels.

CONCLUSION

These findings demonstrate increased severity of OA at higher cartilage AGE levels and provide the first in vivo experimental evidence for a molecular mechanism by which aging may predispose to the development of OA.

A good response to early DMARD treatment of patients with rheumatoid arthritis in the first year predicts remission during follow up

OBJECTIVE

To describe the frequency and duration of remission in the Utrecht rheumatoid arthritis cohort of patients followed since diagnosis, and the clinical and treatment characteristics of patients with remission v those without.

METHODS

In 1990 the Utrecht rheumatoid arthritis cohort study group started a clinical trial in which patients with recent onset of rheumatoid arthritis (<1 year) were randomised into four treatment groups: hydroxychloroquine (n = 169); intramuscular gold (n = 163); methotrexate (n = 166); and pyramid (n = 64). After two years, rheumatologists were allowed to prescribe any disease modifying antirheumatic drug. Remission was defined as: duration of morning stiffness < or =15 min, mean VAS pain < or =10 mm, Thompson joint score < or =10, and ESR < or =30 mm/h during at least six months. Cox regression analysis was used to determine baseline clinical, demographic, and treatment predictors of remission.

RESULTS

Mean follow up duration was 62 months. Thirty six per cent achieved at least one period of remission. Median duration between diagnosis and the first remission period was 15 months for the intramuscular gold group, 18 months for the methotrexate and hydroxychloroquine groups, and 24 months for the pyramid group (NS). Predictors of remission were early response to initial treatment, less pain, rheumatoid factor negativity, and lower joint score at baseline.

CONCLUSIONS

After a mean follow up duration of 62 months, only 36% of the patients had fulfilled the remission criteria at least once. A good response to treatment during the first year seems to be independently associated with remission rather than initial treatment alone.

The clinical effect of glucocorticoids in patients with rheumatoid arthritis may be masked by decreased use of additional therapies

OBJECTIVE

Our previous analysis of patients with early active rheumatoid arthritis (RA) treated with prednisone or placebo revealed the following discrepancy: although a significant retardation of joint damage was observed in the prednisone group compared with the placebo group, no differences in clinical variables between the 2 groups were observed, due to greater use of additional therapy in the placebo group. We sought to investigate whether this discrepancy would extend to variables of well-being.

METHODS

We conducted a double-blind, randomized, placebo-controlled clinical trial of prednisone (10 mg) in patients with RA; the duration of the study was 2 years. Following the placebo-controlled trial, a 1-year open-label followup study was conducted in 81 patients with early (</=1 year) active, previously untreated RA. Forty-one patients were allocated to receive oral prednisone, 10 mg/day, and 40 patients were assigned to the placebo group. Analgesics, nonsteroidal antiinflammatory drugs (NSAIDs), local injections of a glucocorticoid (only when absolutely necessary), and use of physiotherapy were allowed in both groups. After 6 months, sulfasalazine (2 gm/day) could be prescribed as rescue therapy in both groups. At the beginning of the study and every 6 months thereafter, 2 questionnaires (the VDF [Dutch version of the Health Assessment Questionnaire] and the IRGL [Dutch version of the Arthritis Impact Measurement Scales]) were administered. A visual analog scale (VAS) for morning pain was administered every 3 months. Disease activity and radiologic scores were assessed.

RESULTS

VDF scores in the 2 groups were not statistically significantly different. No statistically significant differences between groups were observed in almost all parameters of the IRGL. In the prednisone group (and only at 6 months), the VAS scores for morning pain and general well-being showed improvement comparable with the transient improvement in some of the disease activity variables. In the prednisone group, use of NSAIDs, analgesics, local injections of glucocorticoids, and physiotherapy sessions was approximately 50% that in the placebo group.

CONCLUSION

Although significant retardation of joint damage in the prednisone group indicates better disease control, no differences between the groups for variables of well-being were found. This discrepancy may be attributed to greater use of additional therapy in the placebo group. In future clinical trials, the use of additional therapies should be taken into account when analyzing the differences in effect between drugs.

Pain coping and social support as predictors of long-term functional disability and pain in early rheumatoid arthritis

Pain-related avoidance factors and social resources, as assessed by pain coping and social support, are supposed to have lasting effects on functional disability and pain in chronic pain disorders. As a follow-up to a prospective study demonstrating short-term effects after one year (Behaviour Research and Therapy, 36, 179-193, 1998), the role of pain coping and social support at the time of diagnosis was investigated in relationship to the long-term course of functional disability and pain after three and five years in 78 patients with rheumatoid arthritis (RA), taking into account personality characteristics of neuroticism and extraversion, clinical status and use of medication. In line with findings at the one-year follow-up, results showed that more passive pain coping predicted functional disability at the three-year, but not the five-year follow-up. In addition, low levels of social support at the time of diagnosis consistently predicted both functional disability and pain at the three and five-year follow-ups. Results indicate that pain coping and social support, assessed very early in the disease process, can affect long-term functional disability and pain in RA, and suggest that early interventions focusing on pain-related avoidance factors and social resources for patients at risk may beneficially influence long-term outcomes in RA.

Long-term exposure to silicone breast implants does not induce antipolymer antibodies

The focus of our studies was to determine whether the antipolymer antibody assay (APA) as an objective laboratory assay could contribute to the diagnosis in women with a silicone breast implant (SBI) and complaints/symptomatic disease. We investigated whether a population of symptomatic SBI recipients exists with a high prevalence of APA in the Netherlands. The study participants were selected based on self-reported complaints. In one study their physician was approached for additional information on their disease status. Two groups of 42 women were included in the studies, with a mean SBI exposure of 17 and 16 years, respectively. The participants were clinically examined, and the APA level in serum samples determined. The study population of SBI recipients was categorised in severity subgroups based on the functional capacity, and the study physicians general assessment of pain and disease activity. Positive APA levels were found in 10% of the SBI recipients. Also in control groups 8% showed a positive APA response. After categorisation most (65 of 84) SBI recipients belonged to the limited severity subgroup on an increasing scale of limited, mild, moderate and advanced. Eight were categorised in the mild, four in the moderate, and seven in the advanced severity subgroup. None of the APA positive women were found to belong to the moderate or advanced severity subgroup. Seven of the APA positive women belonged to the limited, and one woman to the mild severity subgroup. In conclusion, we were unable to include a large proportion of severely symptomatic SBI recipients in our study populations. So, we cannot confirm the results of Tenenbaum et al. [1] on the presence of APA in symptomatic SBI recipients. However, our failure in two separate studies to recruit symptomatic SBI recipients suggests that the population of severely symptomatic SBI recipients in the Netherlands is rather small. The number of APA positive responses in our study population was low. In addition, also in the normal population a similar low percentage of positively reacting women were observed. Hence, we cannot recommend the use of the APA assay for diagnostic purposes in the clinical evaluation of SBI recipients with severe complaints/symptoms.

EULAR Recommendations 2003: an evidence based approach to the management of knee osteoarthritis: Report of a Task Force of the Standing Committee for International Clinical Studies Including Therapeutic Trials (ESCISIT)

OBJECTIVES

To update the EULAR recommendations for management of knee osteoarthritis (OA) by an evidence based medicine and expert opinion approach.

METHODS

The literature search and guidelines were restricted to treatments for knee OA pertaining to clinical and/or radiological OA of any compartment of the knee. Papers for combined treatment of knee and other types of OA were excluded. Medline and Embase were searched using a combination of subject headings and key words. Searches for those treatments previously investigated were conducted for January 1999 to February 2002 and for those treatments not previously investigated for 1966 to February 2002. The level of evidence found for each treatment was documented. Quality scores were determined for each paper, an effect size comparing the treatment with placebo was calculated, where possible, and a toxicity profile was determined for each treatment modality.

RESULTS

497 new publications were identified by the search. Of these, 103 were intervention trials and included in the overall analysis, and 33 treatment modalities were identified. Previously identified publications which were not exclusively knee OA in the initial analysis were rejected. In total, 545 publications were included. Based on the results of the literature search and expert opinion, 10 recommendations for the treatment of knee OA were devised using a five stage Delphi technique. Based on expert opinion, a further set of 10 items was identified by a five stage Delphi technique as important for future research.

CONCLUSION

The updated recommendations support some of the previous propositions published in 2000 but also include modified statements and new propositions. Although a large number of treatment options for knee OA exist, the evidence based format of the EULAR Recommendations continues to identify key clinical questions that currently are unanswered.

Stress-vulnerability factors as long-term predictors of disease activity in early rheumatoid arthritis

OBJECTIVE

Stress-vulnerability factors were studied for their ability to predict long-term disease activity in early rheumatoid arthritis.

METHODS

In a prospective study involving 78 recently diagnosed rheumatoid arthritis (RA) patients, the role of personality characteristics (neuroticism, extraversion), physical and psychological stressors (chronic, disease-related stressors of functional disability, pain, disease impact on daily life, as well as major life events), coping and social support at the time of diagnosis was examined to predict changes in clinical indicators of disease activity 1, 3 and 5 years later.

RESULTS

While stress-vulnerability factors failed to predict disease activity at the 1-year follow-up, disease activity at the 3- and 5-year follow-ups was predicted by coping and social support at the time of diagnosis, after adjusting for disease activity at first assessment, other biomedical and psychosocial factors and use of medication. Low levels of social support predicted increased disease activity at the 3-year follow-up, and high avoidance coping predicted increased disease activity at the 3- and 5-year follow-ups.

CONCLUSION

Findings indicate the potential prognostic value of avoidance coping and social support for the long-term course of disease activity in early RA and suggest that the effects of these vulnerability factors predominantly operate in the long term.

Five-year followup of rheumatoid arthritis patients after early treatment with disease-modifying antirheumatic drugs versus treatment according to the pyramid approach in the first year

OBJECTIVE

To evaluate whether the clinical advantages observed after 1 year in a randomized controlled clinical trial, in which 2 treatment strategies were compared (the early disease-modifying antirheumatic drug [DMARD] approach versus the pyramid approach), persist after 5 years.

METHODS

In this study, 238 patients with recently diagnosed rheumatoid arthritis (RA) were randomized to either the pyramid group (n = 56) or the early DMARD group (n = 182). Patients assigned to the pyramid group received nonsteroidal antiinflammatory drugs for at least 1 year after inclusion (the mean +/- SD lag time until first prescription of a DMARD was 14 +/- 9 months). Patients in the early DMARD group were treated with a DMARD immediately after inclusion.

RESULTS

After 5 years, data were available for 44 patients in the pyramid group (79%) and 145 patients in the early DMARD group (80%). No prolongation of the clinical advantages in favor of the early DMARD group, as observed after the first year, was demonstrated. Nevertheless, a significantly shorter delay time until complete response and a higher number of patients with overall clinically relevant improvement at several assessment points were observed in the early DMARD group compared with the pyramid group.

CONCLUSION

The clinical results in favor of the early DMARD group, as observed after the first year, were not as evident after 5 years. This indicates that a more aggressive treatment approach in early RA is required, and that treatment should be continued for a prolonged period of time, in order to maintain the advantages obtained in the first year.

Haemoglobin-derived iron-dependent hydroxyl radical formation in blood-induced joint damage: an in vitro study

OBJECTIVE

It has been reported that joint bleeds cause cartilage damage and that the combination of red blood cells (RBC) plus mononuclear cells (MNC) causes the adverse effects. The present study is to elucidate the mechanism by which blood, as present in whole blood, may cause this cartilage damage.

METHODS

Human cartilage samples were cultured for 4 days in the presence of 50% whole blood, isolated MNC plus RBC, CD14+ cells (monocytes/macrophages) plus RBC, or lysed RBC with interleukin 1beta (IL-1beta; a major catabolic product of activated monocytes/macrophages). Antioxidants were used to investigate the involvement of oxidative stress. A subsequent 12-day culture period in the absence of additions is referred to as the recovery period. Changes in cartilage proteoglycan synthesis were determined at days 4 and 16.

RESULTS

Cartilage cultured in the presence of whole blood, MNC plus RBC, or monocytes/macrophages plus RBC resulted in a prolonged inhibition of proteoglycan synthesis (>90% inhibition at day 16; all three P<0.05). Lysed RBC together with IL-1beta also induced prolonged inhibition of proteoglycan synthesis (>56% of controls, P<0.05). Dimethylsulphoxide (DMSO), scavenging hydroxyl radicals, could reverse the inhibition of cartilage proteoglycan synthesis.

CONCLUSIONS

Based on these results we hypothesize that IL-1beta produced by activated monocytes/macrophages increases the production of hydrogen peroxide by chondrocytes. This in combination with haemoglobin-derived iron from the RBC will result in the formation of hydroxyl radicals in the vicinity of chondrocytes. This mechanism may result in chondrocyte damage and as such be involved in blood-induced cartilage damage.

Selective elimination of synovial inflammatory macrophages in rheumatoid arthritis by an Fcgamma receptor I-directed immunotoxin

OBJECTIVE

To determine whether monocyte/macrophages from rheumatoid arthritis (RA) patients can be selectively eliminated by a toxin-conjugated antibody CD64-ricin A (CD64-RiA) directed toward the high-affinity receptor for IgG (FcgammaRI), exploiting the capacity of FcgammaRI to efficiently endocytose antibody which it has bound.

METHODS

Mononuclear cells from peripheral blood (PB) and synovial fluid (SF) obtained from RA patients were cultured in the presence of CD64-RiA. Cell death of monocyte/macrophages was measured by phenotypic changes (light-scatter patterns and CD14 and FcgammaRI expression) and apoptosis (nuclear DNA fragmentation). We then tested whether CD64-RiA-induced cell death of macrophages affected their capacity to stimulate antigen-induced lymphocyte proliferation and to secrete cytokines. Additionally, the capacity of CD64-RiA to inhibit proinflammatory activity and cartilage degradation by RA synovial tissue explants was evaluated.

RESULTS

Inflammatory macrophages from RA SF expressed elevated levels of FcgammaRI and were selectively eliminated by CD64-RiA via apoptotic cell death. Monocyte/macrophages from RA PB, which had lower levels of FcgammaRI expression, were much less affected. Induction of SF macrophage apoptosis was associated with efficient inhibition of antigen-induced lymphocyte proliferation and a reduction in tumor necrosis factor alpha (TNFalpha) release. Consistent with these effects on SF macrophages, CD64-RiA also inhibited TNFalpha production, interleukin-1beta production, and cartilage-degrading activity of RA synovial tissue explants.

CONCLUSION

Together, these data underscore the crucial role of synovial macrophages in RA joint inflammation and indicate that selective elimination of these cells through FcgammaRI-directed immunotoxins could be a novel approach to the treatment of RA.

Fcgamma receptor expression levels on monocytes are elevated in rheumatoid arthritis patients with high erythrocyte sedimentation rate who do not use anti-rheumatic drugs

OBJECTIVES

Levels of immunoglobulin G (IgG) Fc receptors (FcgammaRs) affect the activity and function of monocytes/macrophages when binding IgG-containing immune complexes. Hence, the expression level of FcgammaRs on monocytic cells may influence inflammation in patients with rheumatoid arthritis (RA). In this study the expression levels of FcgammaRI, IIa and IIIa on peripheral blood monocytes of RA patients were compared with those of healthy controls and related to patient and disease characteristics and the use of disease-modifying anti-rheumatic drugs (DMARDs). In addition, FcgammaR expression levels were determined on RA synovial fluid macrophages and compared with those in RA peripheral blood.

METHODS

Mononuclear cells from peripheral blood and synovial fluid were isolated and FcgammaR expression levels on CD14-positive cells were analysed by flow cytometry. The effects of patient and disease characteristics and the use of DMARDs were assessed.

RESULTS

A high expression level of FcgammaRIIa and high percentages of FcgammaRIIIa-expressing monocytes were found in RA patients with a high erythrocyte sedimentation rate. DMARD-naive early RA patients had higher FcgammaRIIa expression levels but a similar amount of FcgammaRIIIa-positive monocytes compared with RA patients using DMARDs. In synovial fluid, FcgammaRIIa expression levels were lower than in RA peripheral blood, whereas the percentage of FcgammaRIIIa-positive monocytic cells was higher in synovial fluid than in peripheral blood.

CONCLUSIONS

These data point to the involvement of FcgammaRs, specifically FcgammaRIIa and IIIa, in the immune response of RA and suggest that FcgammaR expression levels are susceptible to modulation by DMARD therapy.

Interleukin 10 treatment of patients with rheumatoid arthritis enhances Fc gamma receptor expression on monocytes and responsiveness to immune complex stimulation

OBJECTIVE

Several clinical studies performed with human recombinant interleukin 10 (IL-10) in patients with rheumatoid arthritis (RA) have shown little efficacy. We investigated potentially proinflammatory in vivo effects of IL-10 in humans. We evaluated the upregulation of Fc gamma receptor (Fc gamma R) expression on monocytes/macrophages (and granulocytes) in patients with RA receiving different dosages of IL-10.

METHODS

Together with changes in disease activity and several cell markers, the expression of Fc gamma RI, Fc gamma RIIa, and Fc gamma RIII was determined on granulocytes and monocytes/macrophages from the peripheral blood of 6 patients with active RA before and after treatment with recombinant human IL-10. In addition, the in vitro effect of IL-10 on Fc gamma R expression on monocytes/macrophages in combination with their susceptibility to immune complex induced production of tumor necrosis factor-alpha(TNF-alpha) was assessed.

RESULTS

Clinical improvement was not observed in the IL-10 treated patients (based on ACR20 criteria). Significant decreases in thrombocyte numbers were observed in patients receiving IL-10. No changes in cell markers such as CD14 were found. On the other hand, expression of Fc gamma RI and Fc gamma RIIa on monocytes/macrophages was increased upon high dose IL-10 treatment. Interestingly, increases in expression of Fc gamma RI and Fc gamma RIIa correlated with a decrease in thrombocyte numbers. In vitro, IL-10 similarly upregulated Fc gamma RI and Fc gamma RIIa expression on monocytes/macrophages from RA patients. This was accompanied by increased TNF-a production after immune complex stimulation.

CONCLUSION

These findings indicate that upregulation of Fc gamma R expression in RA with IL-10 treatment may counteract the otherwise antiinflammatory effects of IL-10 by potentiating immune complex mediated proinflammatory responses.

Low-dose glucocorticoids in early rheumatoid arthritis: discordant effects on bone mineral density and fractures?

OBJECTIVE

To investigate the incidence of osteoporotic fractures and effects on bone of low-dose glucocorticoid (GC) monotherapy in a group of previously untreated patients with early active RA we performed a double blind, randomised, placebo-controlled clinical trial. The study duration was 2 years, with an open follow-up during the third year. Patients were randomly allocated to receive 10 mg prednisone or placebo.

METHODS

Non-steroidal anti-inflammatory drugs (NSAIDs) were allowed in both groups. After 6 months sulphasalazine (2 gr daily) could be prescribed as rescue therapy in both groups. Except for 500 mg calcium supplement daily, no specific preventive measures were taken. This was a normal procedure at the time the study was designed (1989-1991). At the start of the study and every 6 months, X-rays of the twelfth thoracic and of all lumbar vertebrae were scored using the Kleerekoper method, and every year biochemical parameters of bone metabolism and bone mineral density (BMD, expressed in T-scores) and bone mineral content (BMC, expressed in g/cm) were assessed.

RESULTS

In the prednisone group there was a higher incidence during the study of lumbar vertebral fractures than in the placebo group: 7 vs 4 respectively. This difference did not reach statistical significance however, probably because of the small numbers. One patient of the prednisone group suffered an osteoporotic fracture of the pelvis. In the 2-year study and the subsequent follow-up year, no other peripheral fractures were seen in either group. No significant changes from baseline in BMD and BMC of the hips were seen in either group during the study and the follow-up year. In the lumbar spine, BMD in the prednisone group decreased although not statistically significantly during the whole study. No correlation between changes in serum osteocalcin and BMD was observed.

CONCLUSION

Low-dose prednisone monotherapy for patients with early active previously untreated RA seems to increase the risk of fractures not only by reducing the BMD but also by changes in bone strength and structure.

Glucocorticoid receptor up-regulation in early rheumatoid arthritis treated with low dose prednisone or placebo

OBJECTIVE

Low or medium dose prednisone in early rheumatoid arthritis (RA), albeit with significant variation in clinical efficacy, reduces the progression of joint damage. The glucocorticoid receptor (GR) number in peripheral mononuclear cells (PBMC) might be helpful to predict which patients will respond to low or medium dose prednisone and therefore do not or will not need higher doses. With this in mind we determined in a double blind, placebo controlled study at baseline and yearly the GR number in PBMC.

METHODS

Eighty-one early RA patients (disease duration less than one year) were included. All patients fulfilled the ACR criteria and were disease modifying antirheumatic drugs (DMARD) and glucocorticoid-naive. They were randomly assigned to treatment with 10 mg prednisone daily or placebo. From all patients disease activity (CRP, number of tender and swollen joints), the radiological joint score, bone mineral density, and the GR number in PBMC were measured annually.

RESULTS

In females the GR number was up-regulated over time in both the prednisone and the placebo group. The same trend was observed in males. No correlations were found between the GR number in the prednisone users at the start of their treatment and changes in radiological scores or bone density after 2 years of treatment. No correlations were found between the GR number at the start and the clinical characteristics after a follow-up of 2 years.

CONCLUSION

The GR number in the PBMC of early RA patients did not predict which patients would be prednisone responders based on clinical or radiological parameters. However, the up-regulation of the GR number in PBMC in early RA patients towards the GR number of healthy subjects during the first two years of their disease course seems to reflect a recovery or compensatory mechanism as a response to an ongoing inflammatory process. This recovery may be not enough to efficiently control the inflammatory situation.

Immature articular cartilage is more susceptible to blood-induced damage than mature articular cartilage: an in vivo animal study

OBJECTIVE

Cartilage of young but skeletally mature dogs is more susceptible to blood-induced damage than that of old dogs. The aim of the present study was to investigate whether cartilage of skeletally immature individuals is even more adversely affected by exposure to blood than that of mature individuals, as suggested by clinical practice experience with humans.

METHODS

Right knees of 3 groups of 6 beagle dogs (skeletally immature, young mature, and old animals) were injected with autologous blood on days 0 and 2. On day 4, cartilage matrix proteoglycan turnover (content, synthesis, and release), synovial inflammation, and cartilage-destructive properties of the synovial tissue were determined and compared with those of the left uninjected control knees.

RESULTS

Subsequent to intraarticular bleeding, cartilage proteoglycan content decreased in an age-dependent manner, with the largest decrease occurring in cartilage of immature animals. Proteoglycan synthesis per cell also decreased in an age-dependent manner, with the largest decrease occurring in the immature animals. Cartilage proteoglycan release increased in all 3 groups, but the decrease was not age dependent. Interestingly, immature animals showed a large increase in cartilage DNA content upon exposure to blood, whereas mature animals did not. Histologic analysis showed a mild synovitis in animals of all ages, but catabolic inflammatory activity was found only in immature animals.

CONCLUSION

Joints of skeletally immature dogs appeared to be more susceptible than joints of mature dogs to the adverse effects of a joint hemorrhage. These data suggest that for humans, specifically young children are at risk for joint damage after a joint hemorrhage.

Interleukin 7 stimulates tumour necrosis factor alpha and Th1 cytokine production in joints of patients with rheumatoid arthritis

BACKGROUND

A large number of activated T cells are found in the joints of patients with rheumatoid arthritis (RA). Interleukin 7 (IL7), a T cell growth factor and a regulator of Th1 and Th2 cytokine production, is produced by synoviocytes from patients with RA.

OBJECTIVE

To investigate the effect on proinflammatory cytokine production of synovial fluid mononuclear cells (SFMC) and the mechanism by which IL7 influences CD4+ T cell activity in patients with RA.

METHODS

In a cross sectional group of patients with RA, IL7 levels were compared with those of healthy controls and related to disease activity. The effect of IL7 on cytokine production was tested by RA SFMC and on SF CD4+ T cells in the presence of mononuclear cells (MC). Production of tumour necrosis factor alpha (TNF alpha), IL1 beta, interferon gamma (IFN gamma), and IL4 was measured by enzyme linked immunosorbent assay (ELISA) and by single cell FACS analysis. Expression of the IL7 receptor alpha chain on CD4+ T cells (essential for IL7 signalling) was assessed. Direct effects of IL7 on isolated synovial fluid (SF) CD4+ T cells were studied by cytokine analysis. By neutralisation of IL12 in MC cultures, indirect effects of IL7 on T cells through accessory cells were studied.

RESULTS

IL7 serum levels were higher in patients with RA than in healthy controls and correlated positively with C reactive protein levels. IL7 stimulated TNFalpha production by SFMC and very potently stimulated IFN gamma and TNF alpha production by SF CD4+ T cells. These effects were probably mediated through the IL7 receptor alpha chain, which was abundantly expressed on SF CD4+ T cells. Besides the direct stimulation of T cell cytokine production by IL7, its action was partly dependent on IL12, indicating that IL7 also stimulates accessory cell function, leading to T cell activation.

CONCLUSION

IL7 stimulates proinflammatory cytokine production of intra-articular CD4+ T cells and accessory cells from patients with RA. The correlation with measures of disease activity indicates that IL7 might substantially contribute to the perpetuation of Th1 and TNF alpha mediated proinflammatory responses in patients with RA.

Differentiation of naive CD4+ T cells towards T helper 2 cells is not impaired in rheumatoid arthritis patients

An impaired differentiation of naive CD4+ T cells towards Th2 cells may contribute to the chronic tissue-destructive T-cell activity in rheumatoid arthritis (RA). The differentiation of naive CD4+ T cells into memory Th2 cells by IL-7 in comparison with that by IL-4 was studied in RA patients and in healthy controls. Naive CD4+ T cells from peripheral blood were differentiated by CD3/CD28 costimulation in the absence of or in the presence of IL-7 and/or IL-4. The production of IFN-gamma and IL-4 was measured by ELISA and by single-cell FACS analysis to indicate Th1 and Th2 cell activity. CD3/CD28 costimulation and IL-7 were early inducers of IL-4 production, but primarily stimulated IFN-gamma production. In contrast, in short-term cultures exogenously added IL-4 did not prime for IL-4 production but suppressed IL-7-induced IFN-gamma production. Upon long-term stimulation of naive CD4+ T cells, IFN-gamma production was differentially regulated by IL-7 and IL-4, but IL-4 production was increased by both IL-7 and IL-4. IL-7 and IL-4 additively induced polarization towards a Th2 phenotype. This susceptibility of naive CD4+ T cells to become Th2 cells upon culture with IL-7 and IL-4 was increased in RA patients compared with that in healthy controls. These findings demonstrate that, in RA patients, differentiation of naive CD4+ T cells towards a Th2 phenotype by CD3/CD28 costimulation, IL-7 and IL-4 is not impaired. The perpetuation of arthritogenic T-cell activity in RA therefore seems not to be the result of intrinsic defects of naive CD4+ T cells to develop towards suppressive memory Th2 cells.

Longterm predictors of anxiety and depressed mood in early rheumatoid arthritis: a 3 and 5 year followup

OBJECTIVE

Heightened levels of anxiety and depressed mood are known to be common consequences of rheumatoid arthritis (RA). We examined the role of stress vulnerability factors in the longterm course of anxiety and depressed mood in patients with early RA. Specifically, the role of personality characteristics (neuroticism, extraversion), physical and psychological stressors (clinical status, disease influence on daily life, major life events), and coping and social support at the time of diagnosis were studied to predict changes in anxiety and depressed mood 3 and 5 years later.

METHODS

Anxiety and depressed mood, predicted from clinical and self-reported assessments of stress vulnerability factors at the time of diagnosis in 78 patients with RA were assessed again after 3 and 5 years.

RESULTS

A worse clinical status, more neuroticism, and lower education level at the time of diagnosis were all significantly related to increased psychological distress at the 3 and 5 year followup. However, the personality characteristics of neuroticism proved to be the most consistent and effective predictor of anxiety and depressed mood after 3 and 5 years, irrespective of initial distress levels, biomedical factors, use of medication, and other stressors or vulnerability factors.

CONCLUSION

Results indicate the prognostic value of personality characteristics for longterm susceptibility to distress in patients with early RA, and emphasize the importance of paying close attention to factors unrelated to RA when screening for patients at risk.

Clinical benefit of joint distraction in the treatment of severe osteoarthritis of the ankle: proof of concept in an open prospective study and in a randomized controlled study

OBJECTIVE

Osteoarthritis (OA) is a degenerative, disabling joint disease that affects >10% of the adult population. No effective disease-modifying treatment is available. In the present study, we used joint distraction, a relatively new treatment in which mechanical contact between the articular surfaces is avoided while intraarticular intermittent fluid pressure is maintained, to treat patients with severe OA of the ankle.

METHODS

Patients with severe ankle OA (n = 57) who were being considered for joint fusion (arthrodesis) were treated with joint distraction in an open prospective study. In addition, a randomized trial was performed in 17 patients to determine whether joint distraction had a better outcome than debridement. A standardized evaluation protocol (physical examination, assessment of pain, mobility, and functional ability) was used, and changes in radiographic joint space width and subchondral sclerosis were measured. Thirty-eight patients in the open study have been followed up for >1 year, with up to 5 years of followup in 7 of them (mean +/- SD followup 2.8 +/- 0.3 years). Patients in the randomized study have been followed up for 1 year.

RESULTS

Significant clinical benefit was found in three-fourths of the 57 patients in the open prospective study. Most interestingly, the improvement increased over time. Radiographic evaluation showed increased joint space width and decreased subchondral sclerosis. Moreover, joint distraction showed significantly better results than debridement.

CONCLUSION

The clinical benefit of joint distraction in the treatment of severe OA is proof of the concept. Although the followup remains relatively short and effects over time remain unpredictable, our study creates possibilities for the treatment of severe OA in general. Considering the high prevalence of OA and the lack of a cure for it, joint distraction as a treatment of severe OA may have great medical, social, and economic impact.

[Glucosamine and chondroitin sulfate as a possible treatment for osteoarthritis]

The nutritional supplements glucosamine and chondroitine sulphate are widely used in the treatment of osteoarthritis. In published studies, glucosamine used in a dosage of 1.5 gram daily is, after a period of 2 to 4 weeks, just as effective as low doses of NSAIDs in alleviating pain. Chondroitine sulphate has been less well investigated. There are indications that it affects the symptoms of osteoarthritis, even though this effect only occurs after a longer period of time. The side effects for both substances are minor. A disease-modifying effect (defined as delay of radiological progression of osteoarthritis) has not been proven.

Standardised nomenclature for glucocorticoid dosages and glucocorticoid treatment regimens: current questions and tentative answers in rheumatology

In rheumatology and other medical specialties there is a discrepancy between the widespread use and the imprecise designation of glucocorticoid treatment regimens. Verbal descriptions of glucocorticoid treatment regimens used in various phases of diseases vary between countries and institutions. Given this background, a workshop under the auspices of the EULAR Standing Committee on International Clinical Studies including Therapeutic Trials was held to discuss this issue and to seek a consensus on nomenclature for glucocorticoid treatment. This report summarises the panel's discussion and recognises that answers derived from consensus conferences are not definitive. Nevertheless, recommendations on glucocorticoid treatment are presented that (1) reflect current and best knowledge available and (2) take into account current clinical practice. A question-answer rationale presentation style has been chosen to convey the messages, to summarise the meeting in a readable format, and to avoid dogmatism.

Selective COX-2 inhibition prevents proinflammatory cytokine-induced cartilage damage

OBJECTIVES

This study evaluated the in vitro effect of the selective cyclooxygenase-2 (COX) inhibitor celecoxib on cartilage matrix turnover under normal and inflammatory conditions.

METHODS

Healthy human articular cartilage tissue alone, in co-culture with peripheral blood mononuclear cells (PBMC) or in the presence of interleukin 1 (IL-1beta) plus tumour necrosis factor alpha (TNF-alpha) was cultured for 7 days in the presence of celecoxib. Changes in cartilage matrix turnover were measured.

RESULTS

No direct effects of celecoxib on healthy normal cartilage were found. Both PBMC and IL-1beta plus TNF-alpha induced strong inhibition of cartilage proteoglycan synthesis and significant enhancement of the release of proteoglycans, diminishing proteoglycan content. Celecoxib was able to reverse these adverse effects up to complete normalization.

CONCLUSIONS

The results suggest that, under the influence of inflammation, COX-2 is up-regulated, which results in disturbance of cartilage matrix turnover. Celecoxib, by diminishing COX-2 activity, prevents these adverse effects without having a direct effect on healthy cartilage.

Down regulation of glucocorticoid receptors in early-diagnosed rheumatoid arthritis

OBJECTIVE

In patients with rheumatoid arthritis (RA) of longer duration, glucocorticoid receptor (GR) down-regulation has been reported without any change in cortisol levels. This phenomenon might play a role in the aetio-pathogenesis of RA. Therefore we studied GR expression, as well as the serum cortisol levels, in patients with recently diagnosed RA.

METHODS

In 81 early diagnosed RA patients with disease duration < 1 year (52F/29M; mean (SD) age 63 (13) years) and in 39 age and sex matched controls (23F/16M; mean age 63 (15) years) blood samples were taken between 8-10 h AM. GR expression (GR-number and GR-affinity), serum cortisol levels, ESR, CRP, painful and swollen joints were measured.

RESULTS

A significantly lower GR-number was found in the female patients compared with female controls: 7.0 versus 9.8fmol/million cells, respectively (difference: 2.8, 95% CI 1.1 - 4.6). Interestingly, also serum cortisol levels were significantly lower in the female patients compared with the female controls: 0.21 versus 0.41 micromol/l, respectively (difference: 0.20, 95% CI 0.12 - 0.28). However, between the male patients and male controls no difference was found in GR expression nor in serum cortisol levels. Neither in female nor in male patients were correlations found between GR expression and parameters of disease activity nor was there a relation between GR expression and serum cortisol levels.

CONCLUSIONS

Changes in GR expression as well as serum cortisol were not a general phenomenon in early diagnosed RA patients, being present only in females and not related to disease activity. Therefore it seems unlikely that GR expression per se is causally involved in the pathogenesis of RA. We cannot preclude that it may be involved in the incidence, severity and course of RA, as this may be differentially regulated in males and females.

Suppression of inflammation and joint destruction in rheumatoid arthritis may require a concerted action of Th2 cytokines

A predominance of T-helper 1 (Th1) activity and a lack of Th2 activity has been documented in the inflamed joints of patients with rheumatoid arthritis (RA). This imbalance is suggested to contribute to activation of, particularly, inflammatory macrophages and B-cells. Th2-mediated immunity, like atopy, is associated with amelioriated inflammation and joint damage in RA patients. Despite the potent anti-inflammatory capacities of two prominent Th2 cytokines in many experimental studies, clinical trials with either human IL-4 or IL-10 in RA patients did not lead to substantial disease suppression. Based on a thorough evaluation of the actions of IL-4 and IL-10 in these studies, it is hypothesized that disease suppression of RA may require the concerted action of suppressive Th2 cytokines or Th2 activity.

16-year remission of rheumatoid arthritis after unusually vigorous treatment of closed dental foci

This report describes a remission of rheumatoid arthritis (RA) of 16 years duration, apparently caused by the extraction of endodontically well-treated, healthy looking teeth. The only clue that the teeth were contributing to the disease pathogenesis in this case of RA was that the patient was able to reproducibly induce severe attacks of arthritis after prolonged, heavy pressure on some of his teeth treated with root canal fillings. After extraction, a small pus layer was found to cover the apices of the clinically healthy looking teeth. The rheumatoid factor (RF) became negative and the patient remained symptom free for the next 16 years. The possible connections between micro-organisms in closed dental foci under constant pressure and the chronicity and exacerbations of RA are discussed.

Avoidance of activity and disability in patients with osteoarthritis of the knee: the mediating role of muscle strength

OBJECTIVE

Avoidance of activity is hypothesized to lead to muscle weakness and consequently, to physical disability. This study was undertaken to validate the avoidance model by providing evidence for the mediating role of muscle weakness in the relationship between avoidance of activity and physical disability in patients with osteoarthritis (OA) of the knee.

METHODS

Data on avoidance of activity, observed physical disability, and muscle strength of the knee in 107 patients with knee OA were analyzed. A series of regression analyses was performed to establish the mediating role of muscle weakness. First, the effect of avoidance of activity on the level of disability was assessed. Next, the relationship between avoidance of activity and muscle strength was established. Finally, the mediating role of muscle strength could be established if the effect of avoidance of activity on disability decreased when muscle strength was taken into account.

RESULTS

Initially, avoidance of activity accounted for 21.5% of variance in disability. Avoidance of activity also accounted for 3.9% of variance in muscle strength. After muscle strength was taken into account, the variance in disability accounted for by avoidance of activity was reduced from 21.5% to 15.7%. Thus, the criteria for establishing the mediating role of muscle strength were met.

CONCLUSION

The results of this study provide evidence for the mediating role of muscle weakness in the relationship between avoidance of activity and disability in patients with knee OA.

[The treatment of chronic inflammatory diseases with monoclonal antibodies against tumor necrosis factor: side effects, contraindications and precautions]

Monoclonal antibodies are increasingly used to modulate immunologically mediated diseases such as rheumatoid arthritis, psoriatic arthritis, systemic lupus erythematosus, Crohn's disease, multiple sclerosis and systemic vasculitis. Constructs of monoclonal antibodies to tumour necrosis factor (TNF) alpha differ with respect to their structure, effects and immunogenic side effects. Clinical experience with TNF alpha-neutralizing therapy has revealed several other side effects over the past few years. The most important is increased infection rates, especially the activation of (latent) tuberculosis, although other opportunistic infections such as listeriosis, Pneumocystis carinii pneumonia, histoplasmosis, candidiasis and aspergillosis have also been reported. Furthermore, results from clinical studies indicate that TNF alpha-neutralizing therapy should not be given to patients with cardiac failure (NYHA class III or IV) or a history of demyelinating disease. An increased incidence of malignancies has not been observed up to now, but data from the long-term follow-up are not yet available.

Fatigue in daily life in patients with primary Sjögren's syndrome and systemic lupus erythematosus

Fatigue is a well-recognized complaint with major impact on daily life in primary Sjögren's syndrome (PSS) and systemic lupus erythematosus (SLE). Previous research has not taken into account several crucial aspects of fatigue. This study examined various aspects of fatigue in the daily life of patients with PSS and SLE and in healthy controls. We compared age-adjusted, repeated measurements of fatigue across the day of female patients with SLE (n = 20, mean age 43.4 +/- 11.3), with PSS (n = 28, mean age 53.7 +/- 13.9) and healthy participants (n = 30, mean age 50.5 +/- 13.4). General and physical fatigue was significantly higher in patients than in healthy participants. Groups did not differ with respect to average levels of reduced motivation or mental fatigue. Both general and physical fatigue and reduced activity varied significantly during the day. Adjusting for depressive symptoms, groups showed significantly different time courses during the day. In healthy participants and patients with SLE, fatigue first decreased and then increased, whereas a rather opposite course-at least for the first part of the day-was observed in patients with PSS. Using an ecologically valid assessment method, we demonstrated substantially higher levels of daily fatigue in SLE and PSS patients as compared to healthy participants, thereby jeopardizing these patients' quality of life. The effect of disease on variations in fatigue over the day should be the subject of further inquiry, especially as it might clarify underlying mechanisms.

Antigen-specific T cell suppression by human CD4+CD25+ regulatory T cells

Anergic/suppressive CD4+CD25+ T cells have been proposed to play an important role in the maintenance of peripheral tolerance. Here we demonstrate that in humans these cells suppress proliferation to self antigens, but also to dietary and foreign antigens. The suppressive CD4+CD25+ T cells display a broad usage of the T cell receptor Vbeta repertoire,suggesting that they recognize a wide variety of antigens. They reside in the primed/memory CD4+CD45RO+CD45RB(low) subset and have short telomeres, indicating that these cells have the phenotype of highly differentiated CD4+ T cells that have experienced repeated episodes of antigen-specific stimulation in vivo. This suggests that anergic/suppressive CD4+CD25+ T cells may be generated in the periphery as a consequence of repeated antigenic encounter. This is supported by the observation that highly differentiated CD4+T cells can be induced to become anergic/suppressive when stimulated by antigen presented by non-professional antigen-presenting cells. We suggest that besides being generated in the thymus, CD4+CD25+ regulatory T cells may also be generated in the periphery. This would provide a mechanism for the generation of regulatory cells that induce tolerance to a wide array of antigens that may not be encountered in the thymus.

Glucocorticoids in rheumatoid arthritis: effects on erosions and bone

Recently, four prospective placebo-controlled studies have further evaluated the disease-modifying properties of glucocorticoids in the treatment of rheumatoid arthritis. These studies irrefutably show that the use of (low) doses of glucocorticoids leads to a significant retardation of the progression of erosions, especially in early rheumatoid arthritis. This effect on erosions seems more impressive and probably more persistent than the well-known relief during low-dose glucocorticoid therapy of symptoms, such as pain, stiffness, and joint scores. The management of the (side) effects of glucocorticoids on bone has clearly improved in the last years. These two developments lead to a further optimizing of glucocorticoid treatment in patients with rheumatoid arthritis.

Glucocorticoid receptor downregulation in early diagnosed rheumatoid arthritis

In patients with rheumatoid arthritis (RA) with a mean duration of six years, glucocorticoid receptor (GR) downregulation has been reported without change in cortisol levels. This phenomenon might play a role in the etiopathogenesis of RA. If this is the case, GR downregulation should also be found in early-diagnosed RA. We compared GR expression and cortisol levels of early RA patients with those of sex and age matched healthy controls. In early (disease duration less than one year) RA patients (52F/29M; mean [SE] age 63 +/- 2 years) and in 39 controls (23F/16M; mean age 63 +/- 2 years) blood samples were taken between 8:00 and 10:00 a.m. GR expression (GR number), cortisol levels (fluorescence polarization immunoassay, FPIA), ESR, CRP, and the presence of swollen and painful knees were determined. RA was diagnosed according to the ACR classification criteria. In early RA a significantly lower GR expression was found compared to controls. Interestingly, cortisol levels were also significantly lower. Both findings were due to the observed differences in the female population. In the male population no differences were found. No correlations were found among parameters of disease activity, nor was there a relation between GR expression and serum cortisol levels. In female patients with early-diagnosed RA a decrease in glucocorticoid receptor expression was found as well as a decrease in cortisol levels. Since normal glucocorticoid receptor expression was found in the male population with early-diagnosed RA, it remains questionable if glucocorticoid receptor expression is causally involved in pathogenesis of RA.

Analgesia and the patient with osteoarthritis

Osteoarthritis is the most common form of arthritis, its prevalence increasing with age: as much as 80% of the population over 75 years show radiologic signs of the condition. Symptoms include pain, stiffness, and functional impairment; however, not all patients are symptomatic. Management starts with nonpharmacologic interventions, followed by pharmacologic means, and ultimately by surgical intervention. The management is multidisciplinary and is tailored to the needs of the individual patient. It is, therefore, a good model of collaborative care: multidisciplinary management of a chronic condition for which the patients themselves coordinate the use of the management options, with information and guidance from health care professionals and written materials, as needed. Guidelines for the management of osteoarthritis have been developed and are applied in different continents. These guidelines are based on searches of the literature and evidence-based interpretation, in combination with expert opinion. Pharmacologic management guidelines state that based on its overall efficacy, toxicity profile, and cost, paracetamol-acetaminophen should be tried first and, if successful, should be used as the preferred long-term analgesic. In patients who do not experience adequate symptomatic relief with paracetamol-acetaminophen, alternative or additional pharmacologic agents should be considered, especially nonsteroidal anti-inflammatory drugs (NSAIDs). When the combination of paracetamol-acetaminophen with NSAIDs fails, tramadol may be given. Most patients with osteoarthritis are able, after discussion with their physician, to manage their symptoms themselves. They make use of educational occupational, and physical advisers, and they use their medication on demand. The basis of this self-administered pharmacologic management is paracetamol-acetaminophen, sometimes in combination with NSAIDs. A promising option for the future is the development of symptomatic slow-acting drugs for osteoarthritis that possess structure-modifying properties.

Evaluation and management of endocrine dysfunction in fibromyalgia

Fibromyalgia-like symptoms such as muscle pain and tenderness, exhaustion, reduced exercise capacity, and cold intolerance, resemble symptoms associated with endocrine dysfunction like hypothyroidism, and adrenal or growth hormone insufficiency. To investigate the potential of management of endocrine abnormalities for relieve of symptoms of patients with fibromyalgia, we reviewed experimental and clinical studies of endocrine functioning and endocrine treatment. Serum GH, androgen, and 24-hour urinary cortisol levels of patients with fibromyalgia tend to be in the lower part of the normal range, while serum levels of thyroid hormone, female sex hormones, prolactin, and melatonin are normal. With exception of GH, these conclusions are based on studies in small samples. With respect to dynamic responsiveness of the hypothalamic-pituitary-adrenal (HPA) axis, the dexamethasone suppression test and stimulation with ACTH show normal results, while patients show marked ACTH hypersecretion in response to severe acute stressors, perhaps indicative of chronic CRH hyposecretion. This finding and slightly altered responsiveness of growth hormone, thyroid hormone, and prolactin in pharmacologic stimulation tests suggest a central rather than peripheral origin of endocrine deviations. Because hormone level deviations were not severe, occurred in subgroups of patients only, and few controlled clinical trials were performed, there is--unless future research shows otherwise--little support for hormone supplementation as a general therapy in the common patient with fibromyalgia. In patients with clinically overt hormone deficiency, hormonal supplementation is an option. In patients with hormone levels that are in the lower part of the normal range, interventions aimed at pain, fatigue, sleep or mood disturbance, and physical deconditioning may indirectly improve endocrine functioning.

Steady progression of osteoarthritic features in the canine groove model

OBJECTIVE

Recently we described a canine model of osteoarthritis (OA), the groove model with features of OA at 10 weeks after induction, identical to those seen in the canine anterior cruciate ligament transection (ACLT) model. This new model depends on cartilage damage accompanied by transient intensified loading of the affected joint. The present study evaluates this groove model at 20 and 40 weeks after induction, to assess whether the osteoarthritic features progress in time.

METHODS

Grooves were made in the femoral condyles of one knee without damaging the subchondral bone. After surgery the dogs were forced to load the experimental joint 3 days per week (4 hours/day) for 20 weeks by fixing the contralateral control limb to the trunk. After 20 weeks and 40 weeks (the last 20 weeks normal loading) joints were analysed for biochemical and histological features of OA.

RESULTS

All biochemical cartilage parameters were indicative of OA and all these parameters suggested a slow progression of degeneration over time from 20 to 40 weeks after induction, statistically significant for synthesis and content of proteoglycans as well as Mankin grade. Synovial inflammation, which was mild, diminished slightly in time.

CONCLUSION

The degenerative joint damage in the canine groove model is slowly progressive over time in the first year. The cartilage degeneration is induced by a one-time trauma and is not primarily mediated by synovial inflammation, which gives this model unique characteristics compared to presently available models for studying early osteoarthritic features in vivo. In the groove model the effect of treatment of cartilage damage is not counteracted by permanent joint instability or hampered by inflammation. Therefore, the model might be more sensitive to detect effects of therapy, aimed at cartilage protection and repair.

Study to determine the presence of antipolymer antibodies in a group of Dutch women with a silicone breast implant

OBJECTIVE

To determine whether there exists a population of Dutch women with a high prevalence of antipolymer antibodies (APA) and severe health complaints/symptoms, and exposure to a silicone breast implant (SBI). As the antigen-specific nature of the antipolymer antibody has not yet been established, we refer to the term polymer binding immunoglobulins.

METHODS

The study population was selectedfrom a voluntary registry of SBI recipients of a Dutch consumers organisation. The final selection was based on the severity of self-reported complaints in a questionnaire. A total of 42 SBI recipients were included in the study, clinically examined and blood samples were obtained.

RESULTS

In 12 of 42 SBI recipients an increase in the level of polymer binding immunoglobulins was detected compared to a negative reference sample, 3 of these 12 showing a positive and 9 a weakly positive response. In 3 out of 12 non-SBI recipients, included for control on the performance of the APA assay, an increased level of polymer binding immunoglobulins was demonstrated, 2 of these 3 showing a positive and 1 a weakly positive response. The study population of SBI recipients was categorised in severity subgroups (limited, mild, moderate, advanced) based on the fuctional capacity and the physicians general assessment of pain and disease activity. Most (34 of 42) SBI recipients belonged to the limited severity subgroup.

CONCLUSION

Our methods failed to select a group of severely symptomatic Dutch SBI recipients reported to have a high prevalence of polymer binding antibodies. A discrepancy was present between the self reported severe complaints and the observed mild clinical symptoms. In the group of SBI recipients with self reported severe complaints recruited we did not find a high prevalence of polymer binding immunoglobulins. SBI exposure (mean 17 years) did not result in induction of polymer binding immunoglobulins in this minimal symptomatic study group.

Crosslinking by advanced glycation end products increases the stiffness of the collagen network in human articular cartilage: a possible mechanism through which age is a risk factor for osteoarthritis

OBJECTIVE

Age is an important risk factor for osteoarthritis (OA). During aging, nonenzymatic glycation results in the accumulation of advanced glycation end products (AGEs) in cartilage collagen. We studied the effect of AGE crosslinking on the stiffness of the collagen network in human articular cartilage.

METHODS

To increase AGE levels, human adult articular cartilage was incubated with threose. The stiffness of the collagen network was measured as the instantaneous deformation (ID) of the cartilage and as the change in tensile stress in the collagen network as a function of hydration (osmotic stress technique). AGE levels in the collagen network were determined as: Nepsilon-(carboxy[m]ethyl)lysine, pentosidine, amino acid modification (loss of arginine and [hydroxy-]lysine), AGE fluorescence (360/460 nm), and digestibility by bacterial collagenase.

RESULTS

Incubation of cartilage with threose resulted in a dose-dependent increase in AGEs and a concomitant decrease in ID (r = -0.81, P < 0.001; up to a 40% decrease at 200 mM threose), i.e., increased stiffness, which was confirmed by results from the osmotic stress technique. The decreased ID strongly correlated with AGE levels (e.g., AGE fluorescence r = -0.81, P < 0.0001). Coincubation with arginine or lysine (glycation inhibitors) attenuated the threose-induced decrease in ID (P < 0.05).

CONCLUSION

Increasing cartilage AGE crosslinking by in vitro incubation with threose resulted in increased stiffness of the collagen network. Increased stiffness by AGE crosslinking may contribute to the age-related failure of the collagen network in human articular cartilage to resist damage. Thus, the age-related accumulation of AGE crosslinks presents a putative molecular mechanism whereby age is a predisposing factor for the development of OA.

[The Dutch College of General Practitioners' "Gout" Standard: a response from rheumatologists]

The authors (rheumatologists) agree with most recommendations of the Dutch College of General Practitioners' guidelines for the diagnosis and management of gout. The most important criticism concerns the supposed diagnostic value of serum urate levels: close examination of the data suggests that this value is very limited.

The canine 'groove' model, compared with the ACLT model of osteoarthritis

OBJECTIVE

The frequently used anterior cruciate ligament transection (ACLT) model of osteoarthritis (OA) in the dog, makes use of a permanent trigger (joint instability) for inducing degenerative changes. The present study evaluates a canine model of degenerative cartilage damage, mimicking OA, which is induced without making use of permanent joint instability.

METHODS

The articular cartilage of the weight-bearing areas of the femoral condyles in one knee of ten beagle dogs was damaged by making grooves, without damaging the subchondral bone. Surgery was followed by 10 weeks intensified loading of the affected joint. Subsequently, joint damage and inflammation were evaluated. The effects were compared with those of the ACLT model.

RESULTS

Histological analysis showed chondrocyte clusters around cartilage lesions and moderate loss of proteoglycans in the 'groove' model. Synovial inflammation was mild. Biochemical analysis of cartilage showed changes in matrix proteoglycan turnover, proteoglycan content, and collagen damage, all characteristics of OA. Synovial fluid MMP-1, -3 and -13 activity was enhanced. Changes were found in condyles and plateau, were similar for all animals tested, and were similar to the changes observed in the ACLT model.

CONCLUSION

The presently described canine 'groove' model shows characteristics identical to those seen in the ACLT model but differs in a way that the changes are induced without joint instability. The latter is expected to make the 'groove' model more sensitive to treatment.

Low-dose prednisone therapy for patients with early active rheumatoid arthritis: clinical efficacy, disease-modifying properties, and side effects: a randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

Oral glucocorticoids combined with disease-modifying antirheumatic drugs are beneficial and retard radiologic joint damage in rheumatoid arthritis.

OBJECTIVE

To investigate the clinical efficacy, disease-modifying properties, and side effects of low-dose glucocorticoids as monotherapy for previously untreated patients with early active rheumatoid arthritis.

DESIGN

2-year randomized, double-blind, placebo-controlled clinical trial.

SETTING

2 outpatient rheumatology clinics.

PATIENTS

81 patients with early active rheumatoid arthritis who had not been treated with disease-modifying antirheumatic drugs.

INTERVENTION

41 patients were assigned to 10 mg of oral prednisone per day, and 40 were assigned to placebo. Nonsteroidal anti-inflammatory drugs were allowed in both groups. After 6 months, sulfasalazine (2 g/d) could be prescribed as rescue medication.

MEASUREMENTS

Clinical variables were assessed at baseline and every 3 months; radiologic studies were performed every 6 months. Adverse effects were documented every 3 months.

RESULTS

In the first 6 months, the prednisone group showed more clinical improvement than the placebo group. This effect was not seen after 6 months except in grip strength and the 28-joint score for tenderness. Use of additional therapies was significantly less common in the prednisone group, particularly in the first 6 months. More than 65% of those who completed the study were not taking sulfasalazine. After month 6, radiologic scores showed significantly less progression in the prednisone group than in the placebo group. No clinically relevant adverse effects were observed, except for a higher incidence of osteoporotic fractures in the prednisone group.

CONCLUSIONS

Prednisone, 10 mg/d, provides clinical benefit, particularly in the first 6 months, and substantially inhibits progression of radiologic joint damage in patients with early active rheumatoid arthritis and no previous treatment with disease-modifying antirheumatic drugs. Because of their limited disease-modifying effects, glucocorticoids should be combined with disease-modifying antirheumatic drugs in patients with rheumatoid arthritis.

Crosslinking by advanced glycation end products increases the stiffness of the collagen network in human articular cartilage: a possible mechanism through which age is a risk factor for osteoarthritis

OBJECTIVE

Age is an important risk factor for osteoarthritis (OA). During aging, nonenzymatic glycation results in the accumulation of advanced glycation end products (AGEs) in cartilage collagen. We studied the effect of AGE crosslinking on the stiffness of the collagen network in human articular cartilage.

METHODS

To increase AGE levels, human adult articular cartilage was incubated with threose. The stiffness of the collagen network was measured as the instantaneous deformation (ID) of the cartilage and as the change in tensile stress in the collagen network as a function of hydration (osmotic stress technique). AGE levels in the collagen network were determined as: Nepsilon-(carboxy[m]ethyl)lysine, pentosidine, amino acid modification (loss of arginine and [hydroxy-]lysine), AGE fluorescence (360/460 nm), and digestibility by bacterial collagenase.

RESULTS

Incubation of cartilage with threose resulted in a dose-dependent increase in AGEs and a concomitant decrease in ID (r = -0.81, P < 0.001; up to a 40% decrease at 200 mM threose), i.e., increased stiffness, which was confirmed by results from the osmotic stress technique. The decreased ID strongly correlated with AGE levels (e.g., AGE fluorescence r = -0.81, P < 0.0001). Coincubation with arginine or lysine (glycation inhibitors) attenuated the threose-induced decrease in ID (P < 0.05).

CONCLUSION

Increasing cartilage AGE crosslinking by in vitro incubation with threose resulted in increased stiffness of the collagen network. Increased stiffness by AGE crosslinking may contribute to the age-related failure of the collagen network in human articular cartilage to resist damage. Thus, the age-related accumulation of AGE crosslinks presents a putative molecular mechanism whereby age is a predisposing factor for the development of OA.