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B A Michel

Publications and source records attributed to B A Michel.

At least 19 recordsLinked to original sources
PubMed2006

Analgesic action of acetaminophen in symptomatic osteoarthritis of the knee.

OBJECTIVES: The study was designed to investigate the analgesic effects and mechanisms of acetaminophen (paracetamol) in symptomatic osteoarthritis (OA) of the knee. METHODS: Twenty patients with symptomatic OA were randomly allocated to two groups treated with either acetaminophen or rofecoxib for 3 months. Visits and measurements were scheduled upon entry (T0), at month 1 (T1) and at month 3 (T3). The intensity of joint pain was evaluated with a 100-mm visual analogue scale (VAS). The physical function of the affected knee was evaluated with a questionnaire comparable to the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC). Levels of serotonin, substance P (SP) and beta-endorphin (BEND) were determined with commercial enzyme-linked immunoassay kits. The expression of kappa opioid receptor (KOR) in peripheral mononuclear blood cells (PBMCs) was quantified by real-time PCR. RESULTS: Both acetaminophen and rofecoxib relieved pain considerably but with different kinetics, and affected different biomarkers. Rofecoxib appeared to be more efficient, reducing pain intensity by 56% at T1 (P<0.01), whereas acetaminophen reduced it by only 29%. Physical function improved in both groups by T3. Correlated with the pain relief, acetaminophen significantly reduced plasma BEND levels, whereas rofecoxib did not do so. In both groups plasma SP levels were elevated compared with T0. A reduction in serum serotonin was detected in the rofecoxib group at T1 (P=0.004) but had recovered at T3. No changes in KOR mRNA in PBMCs were observed in either group. CONCLUSIONS: There is a correlation between reduction in circulating BEND and OA pain relief in patients treated with acetaminophen.

Acetaminophen↗
PubMed2006

[History and clinical examination in rheumatology--key to diagnosis and prognosis].

History and clinical examination are key to diagnosis and prognosis in rheumatology. In the area of soft tissue rheumatism, there is no other diagnostic possibility which could replace clinical examination. Clinical examination also plays a very important role in the diagnosis of the other rheumatic disorders. With a competent clinical examination one can often eliminate the need for additional costly and/or time consuming investigations. In addition, diagnosing by purely careful and competent clinical examination is a highly gratifying activity for the medical doctor. The competent examiner should also be able to derive prognostic conclusions directly from the clinical examination. This is especially important for the more frequent disorders such as soft tissue rheumatism or back problems, where diagnostic imaging is only helpful if interpreted in the context of the pertinent clinical question.

Clinical Competence↗
PubMed2005

Trichostatin A sensitises rheumatoid arthritis synovial fibroblasts for TRAIL-induced apoptosis.

BACKGROUND: Histone acetylation/deacetylation has a critical role in the regulation of transcription by altering the chromatin structure. OBJECTIVE: To analyse the effect of trichostatin A (TSA), a streptomyces metabolite which specifically inhibits mammalian histone deacetylases, on TRAIL-induced apoptosis of rheumatoid arthritis synovial fibroblasts (RASF). METHODS: Apoptotic cells were detected after co-treatment of RASF with TRAIL (200 ng/ml) and TSA (0.5, 1, and 2 micromol/l) by flow cytometry using propidium iodide/annexin-V-FITC staining. Cell proliferation was assessed using the MTS proliferation test. Induction of the cell cycle inhibitor p21Waf/Cip1 by TSA was analysed by western blot. Expression of the TRAIL receptor-2 (DR5) on the cell surface of RASF was analysed by flow cytometry. Levels of soluble TRAIL were measured in synovial fluid of patients with RA and osteoarthritis (OA) by ELISA. RESULTS: Co-treatment of the cells with TSA and TRAIL induced cell death in a synergistic and dose dependent manner, whereas TRAIL and TSA alone had no effect or only a modest effect. RASF express DR5 (TRAIL receptor 2), but treatment of the cells with TSA for 24 hours did not change the expression level of DR5, as it is shown for cancer cells. TSA induced cell cycle arrest in RASF through up regulation of p21Waf1/Cip1. Levels of soluble TRAIL were significantly higher in RA than in OA synovial fluids. CONCLUSION: Because TSA sensitises RASF for TRAIL-induced apoptosis, it is concluded that TSA discloses sensitive sites in the cascade of TRAIL signalling and may represent a new principle for the treatment of RA.

Aged↗
PubMed2004

Galectin-3 is induced in rheumatoid arthritis synovial fibroblasts after adhesion to cartilage oligomeric matrix protein.

BACKGROUND: Galectin-3 is expressed in the synovial tissue of patients with rheumatoid arthritis (RA), particularly at sites of joint destruction. OBJECTIVE: To explore the possibilities that galectin-3 is induced either by proinflammatory cytokines or by adhesion to cartilage components. METHODS: Cell culture plates were coated with fibronectin, collagens I-VI, or cartilage oligomeric matrix protein (COMP), and the suspended cells were then added. The medium was changed after 1 hour at 37 degrees C. Adherent cells were further incubated for 18 hours in the presence or absence of tumour necrosis factor alpha (TNF alpha) or interleukin 1 beta. Cells were pretreated with murine IgG1, anti-CD29, -CD51, -CD61 (integrins), or -CD3 monoclonal antibodies and transferred to culture plates coated with COMP. Adherent cells were counted by light microscopy. The expression of intracellular galectin-3, or cell surface CD29, CD51, and CD61 was determined by flow cytometry before and after adhesion. RESULTS: Four times more RA synovial fibroblasts (SF) than osteoarthritis SF adhered to COMP. RA SF presented more cell surface integrins, and monoclonal antibodies against CD51 inhibited the adhesion to COMP by 80%. TNF alpha reduced the expression of CD61 and the adhesion to COMP, but did not reverse the adhesion once it had taken place. The adhesion of RA SF to COMP was found to increase the intracellular level of galectin-3. In contrast, intracellular galectin-3 decreased after exposure to TNF alpha. CONCLUSION: The increase of galectin-3 occurs after adhesion to COMP, and the alpha V beta 3 receptor (CD51/CD61) has a pivotal role in this process.

Arthritis, Rheumatoid↗
PubMed2004

Targeting cathepsin L (CL) by specific ribozymes decreases CL protein synthesis and cartilage destruction in rheumatoid arthritis.

The present study was undertaken to examine whether ribozymes cleaving specifically cathepsin L (CL) mRNA are able to decrease the synthesis of CL protease in rheumatoid arthritis synovial fibroblasts (RA-SF) and thereby reduce the invasiveness into cartilage both in vitro and in the SCID mouse coimplantation model of RA. Two different ribozymes that cleave CL mRNA specifically at positions 533 (RzCL533) and 790 (RzCL790) were generated. Using retroviral gene transfer, RA-SF were transduced with the ribozyme constructs or the empty vector. To examine the effect of the ribozymes on the mRNA level, quantitative analysis for CL mRNA was performed using real-time PCR. For evaluation on the protein level, ELISA using specific anti-CL antibodies was performed. In addition, transduced RA-SF were examined in vitro in a three-dimensional destruction assay evaluating their ability to degrade extracellular matrix produced by human chondrocytes. Matrix destruction was monitored by the release of soluble glycosaminoglycans (sGAG). Using the in vivo SCID mouse coimplantation model of RA, RzCL533-transduced RA-SF and control cells were coimplanted with human cartilage for 60 days. After being killed, invasion of RA-SF into the cartilage was evaluated by using a semiquantitative score. Transduction of RA-SF with RzCL533 and RzCL790 ribozymes decreased significantly the expression of CL mRNA to 44% (range 25-62%) and 20% (range 1-43%), respectively, when compared to mock-transduced cells. The protein concentration of CL in the cell culture supernatants of transduced RA-SF was decreased from 16.0 ng/ml in the mock constructs to 4.1 and 8.2 ng/ml (mean), respectively. Using the in vitro cartilage destruction assay, the release of sGAG decreased to 46 and 60%, respectively, after 14 days when compared to mock-transduced cells. In the SCID mouse coimplantation model of RA, RzCL533-transduced RA-SF revealed a significant lower cartilage invasion when compared to mock and untransduced cells. Using retroviral gene transfer, ribozymes cleaving CL mRNA inhibit specifically the synthesis of this matrix-degrading enzyme and reduce cartilage destruction in in vitro and in vivo models. Our study therefore suggests that ribozymes targeting CL could be a novel and efficient tool to inhibit joint destruction in RA.

Animals↗
PubMed2004

Increased DNA fragmentation and ultrastructural changes in fibromyalgic muscle fibres.

OBJECTIVE: To determine whether there is evidence of increased DNA fragmentation and ultrastructural changes in muscle tissue of patients with fibromyalgia (FM) compared with healthy controls. METHODS: Muscle tissues from 10 community residents with FM and 10 age and sex matched healthy controls were examined "blindly" for the presence of DNA fragmentation by two different methods: terminal deoxynucleotidyl transferase (TdT) staining (TUNEL) and the FragEL-Klenow DNA fragmentation detection kit. Ultrastructural analysis of tissue was performed by electron microscopy. RESULTS: DNA fragmentation was detected by both methods in 55.4 (SEM 2.5)% of the nuclei in muscle tissue of patients with FM compared with 16.1 (4.1)% (p<0.001) of the nuclei in healthy controls. Contrary to expectation, no typical features of apoptosis could be detected by electron microscopy. The myofibres and actin filaments were disorganised and lipofuscin bodies were seen; glycogen and lipid accumulation were also found. The number of mitochondria was significantly lower in patients with FM than in controls and seemed to be morphologically altered. CONCLUSION: The ultrastructural changes described suggest that patients with FM are characterised by abnormalities in muscle tissue that include increased DNA fragmentation and changes in the number and size of mitochondria. These cellular changes are not signs of apoptosis. Persistent focal contractions in muscle may contribute to ultrastructural tissue abnormalities as well as to the induction and/or chronicity of nociceptive transmission from muscle to the central nervous system.

Adult↗
PubMed2004

Discrepancy between mRNA and protein expression of tumour suppressor maspin in synovial tissue may contribute to synovial hyperplasia in rheumatoid arthritis.

OBJECTIVE: To investigate the expression of maspin in RA synovial tissue and compare it with the expression in osteoarthritis (OA) and normal synovial tissue (NS). METHODS: Using specific primers for maspin, a 237 bp fragment was amplified from cDNA obtained from cultured RA, OA, and normal synovial fibroblasts (SF) by RT-PCR. Additionally, mRNA expression levels were determined quantitatively by real time PCR. mRNA expression of maspin was investigated on snap frozen and paraffin embedded synovial tissue sections by in situ hybridisation. Immunohistochemistry was used to identify the cell type expressing maspin. SDS-PAGE and western blotting were performed to evaluate the protein expression in cultured SF. To confirm protein synthesis in situ, immunohistochemistry with specific anti-maspin antibodies was performed in synovial tissue sections of patients with RA. RESULTS: RT-PCR showed expression of maspin in all cDNA samples from cultured SF. Maspin mRNA was found to be decreased in RA SF twofold and 70-fold compared with OA SF and NS SF, respectively. Maspin mRNA was expressed in RA, OA, and normal synovial tissue. Importantly, maspin transcripts were also found at sites of invasion into cartilage and bone. At the protein level, maspin could be detected in RA and, less prominently, OA SF. In RA synovial tissue, maspin protein was detected in only a few synovial lining cells. CONCLUSION: Maspin is expressed intensively in RA SF at the mRNA level, but only slightly at the protein level, possibly owing to down regulation of maspin; this may contribute to the hyperplasia of synovial tissue in RA.

Adult↗
PubMed2003

Rheumatologists' opinions on the feasibility of a measurement feedback system in rheumatoid arthritis and the influence of motivation.

OBJECTIVE: To assess rheumatologists' opinions about the feasibility of a measurement feedback system in rheumatoid arthritis (RA) and to analyse if motivational aspects play a role in assessing the value of the system and in determining the extent to which it is used. METHODS: A survey sample (n=105) was randomly selected from participants of a measurement feedback system. A survey questionnaire assessed opinions on system outcome, structures and processes, motivation and overall satisfaction. Survey results are given descriptively and groups differing in motivation are compared. RESULTS: The overall response rate was 62%. The system was generally perceived to fulfil its aims, but the effort required to use the system was rated less positive. Rheumatologists had as their motivation either 'science/obligation' or 'individual patient evaluation'. Rheumatologists with the latter motivation were more satisfied with the measurement feedback system, perceived its feasibility as better, and made more use of it. CONCLUSION: Motivation for participating in a measurement feedback system has a significant impact on overall satisfaction with the system and the use of the system. Influencing motivation and reduction of the amount of effort required to use the system might increase overall acceptance.

Arthritis, Rheumatoid↗
PubMed2003

[Osteoporosis].

Explore the source record for details and available documents.

Aged↗
PubMed2003

[Therapy of osteoporosis: bisphosphonates, SERM's, teriparatide and strontium].

The therapy of osteoporosis is mostly based upon the use of drugs which inhibit bone resorption. Among these, the bisphosphonate family is the best known and mostly used by clinicians. Both second and third generation bisphosphonates, like alendronate and risedronate, are now available as weekly tablets which have facilitated the patient compliance to treatment together with a decreased occurrence of gastrointestinal side effects. These compounds are used efficiently to treat postmenopausal osteoporosis and osteoporosis of men as well. Their use did provide good evidence of increased bone mineral density (BMD) and a reduction in fracture rates. The use of intravenous bisphosphonates such as Zoledronate, Ibandronate and Pamidronate remains in most of the cases limited to special indications such as intolerance to the oral formulations and treatment of patients with bone metastases. The selective estrogen modulators (SERM's) family is limited to a single product on the market as of now, Raloxifene, which does inhibit bone resorption and is well documented by postmenopausal women to increase BMD and reduce vertebral fractures. In addition, a large range of positive nonosseous effects have been documented such as the reduction of the incidence of breast cancer. Other substances do have a strong anabolic effect such as Teriparatide, a recombinant human formulation of PTH 1-34. This compound has demonstrated good efficacy in postmenopausal women, increasing vertebral and hip BMD and reducing the incidence of fractures at both sites. The exact role of Teriparatide in the clinical setting is still open but its overall impact in the therapy of osteoporosis could be major due to its major efficiency over shorter periods of time. Strontium ranelate, a new divalent Strontium salt taken orally, acts both as an anti-catabolic and anabolic agent. The first results provided with strontium ranelate are very promising due to its major effect on the increase in BMD both at the vertebral and hip sites and its ability to reduce the incidence of fractures at both locations. Additional data are awaited to confirm these initial positive results.

Aged↗
PubMed2003

p53 in rheumatoid arthritis synovial fibroblasts at sites of invasion.

OBJECTIVE: To analyse the functional response of p53 in rheumatoid arthritis synovial fibroblasts (RASF) in vitro and in vivo and to investigate whether activation of p53 modulates the destructive process of RASF. METHODS: RASF and controls grown on chamber slides were either directly examined with DO7 anti-p53 antibodies by immunofluorescence or irradiated with 10 Gy x rays and analysed time dependently for the expression of p53. The percentage of positive cells was evaluated by a quantitative scoring system. RASF and normal (N) SF cultured in vitro were co-implanted with human cartilage in SCID mice for 60 days. Consecutively, the invasion score was evaluated, and the number of p53 positive cells was determined at the sites of invasion by immunohistochemistry. In addition, synovial tissues from RA, osteoarthritis, and normal synovia were stained with DO7 antibodies. RESULTS: In vitro the rate of expression of p53 in RASF was low (<5%), but transiently inducible by ionising irradiation (50%). In vitro low p53 expressing RASF disclosed, when invading articular cartilage, a nuclear p53 signal in 20% of the cells, indicating the induction of p53 in a distinct population of RASF during the invasive process. CONCLUSIONS: These data suggest an inductive p53 response at sites of cartilage invasion during the destructive process driven by activated RASF.

Animals↗
PubMed2003

Effectiveness of a measurement feedback system on outcome in rheumatoid arthritis: a controlled clinical trial.

BACKGROUND: With the help of a measurement feedback system, the treatment strategy for individual patients with rheumatoid arthritis (RA) can be adjusted to achieve optimal control of disease activity. OBJECTIVE: To study whether a measurement feedback system is effective in reducing disease activity in patients with RA. METHODS: Forty eight rheumatologists and 264 patients participated in a controlled clinical trial. A three month control period was followed by a 12 month period, where feedback on disease activity, disability, and damage was provided to the rheumatologist. The primary outcome measure was the rheumatoid arthritis disease activity index (RADAI). RESULTS: The feedback system was used for 142/228 (62%) patients. Disease modifying antirheumatic drug changes occurred in 69/169 (41%) patients. In patients with high disease activity and feedback use (n=70), the RADAI decreased in the feedback period by -0.27 points per 30 days (p<0.05), as compared with the control period. Patients for whom the feedback system was used had a better outcome than non-users. CONCLUSION: Much more training on the use of a feedback system and outcome measures, as well as the inclusion of explicit treatment guidelines will be necessary to increase the clinical use of measurement feedback and, possibly, to reduce disease activity for a larger number of patients with RA.

Acute Disease↗
PubMed2002

The ICIDH-2 as a framework for the assessment of functioning and disability in rheumatoid arthritis.

OBJECTIVE: To investigate by a cross sectional study in patients with rheumatoid arthritis (RA) the relationship between measures of impairment, activity limitation, and participation of the model of functioning and disability (ICIDH-2). METHODS: Inclusion data of patients with RA (n=803) from the Swiss Clinical Quality Management Group were used. Impairments were measured by the Short Form-36 (SF-36) bodily pain scale, rheumatoid arthritis disease activity index (RADAI), disease activity score (DAS28), and radiographic scoring (x ray). Activity limitation was measured with the Health Assessment Questionnaire (HAQ) and the SF-36 physical functioning scale. Participation was measured with the SF-36 role and social functioning scales. Spearman (partial) correlations were used for analysis. RESULTS: Impairment and activity limitation dimensions of the ICIDH-2 model are related; correlations with the HAQ were: SF-36 bodily pain (r(s)=-0.61), RADAI (r(s)=0.58), DAS28 (r(s)=0.49), and x ray (r(s)=0.35). Similar correlations were found for SF-36 physical functioning. Activity limitation and participation restriction dimensions are also related: the HAQ correlates well with SF-36 role-physical (r(s)=-0.53) and SF-36 social functioning (r(s)=-0.43); SF-36 physical functioning correlates similarly. For impairment and participation restriction dimensions only SF-36 bodily pain is substantially correlated (r(s)=0.47 and 0.48) with SF-36 role-physical, after correcting for the influence of the activity limitation dimension (HAQ and SF-36 physical functioning). CONCLUSIONS: In this cross sectional study of patients with RA, impairments are associated with activity limitations, and activity limitations are associated with participation restrictions. Pain is the only impairment directly associated with participation restrictions. Based on the results of this study, it is strongly recommended that the ICIDH-2 framework is used in clinical trials and observational studies including the assessment of disease consequences in RA.

Activities of Daily Living↗
PubMed2001

Responsiveness of the self-assessed rheumatoid arthritis disease activity index to a flare of disease activity.

OBJECTIVE: To assess the responsiveness of the Rheumatoid Arthritis Disease Activity Index (RADAI) to increases in disease activity, using the occurrence of a flare of disease activity as an external standard. METHODS: A post hoc analysis was performed on data from a randomized, double-blind, controlled trial of methotrexate versus type II collagen in 92 patients with rheumatoid arthritis (RA). Responsiveness was analyzed by 1) correlating change in the RADAI score with change in the Disease Activity Score (DAS28), 2) determining the RADAI's ability to detect a disease flare by plotting a receiver operating characteristic (ROC) curve, and 3) using a responsiveness statistic, the standardized effect size (SES). The contribution of the single RADAI items to the change in total RADAI score was analyzed by the item score change in absolute value, the item responsiveness by the standardized response mean, and the correlation of item score change with total RADAI score change by Cronbach's alpha. RESULTS: Changes in the RADAI score correlated strongly with changes in the DAS28 (R2 = 0.70, P < 0.0001). The area under the ROC curve for the RADAI was 0.88 (95% confidence interval 0.78-0.95), which was similar to that for the DAS28. The SES for the RADAI was 1.56, which was also similar to that for the DAS28. The RADAI items of past global disease activity and morning stiffness contributed least to the total score change. CONCLUSION: This study provides evidence that the RADAI is sensitive to relevant increases in disease activity in RA patients. The RADAI may complement clinical measures in clinical studies, or may be used as a proxy for disease activity in epidemiologic studies.

Arthritis, Rheumatoid↗
PubMed2001

Cysteine protease activity is up-regulated in inflamed ankle joints of rats with adjuvant-induced arthritis and decreases with in vivo administration of a vinyl sulfone cysteine protease inhibitor.

OBJECTIVE: Cysteine proteases are postulated to play a role in tissue destruction in the joints of animals with arthritis. The purpose of the present study was to confirm the concept that cysteine proteases are enzymes involved in the pathology of rheumatoid arthritis (RA). METHODS: Arthritis was induced in Lewis rats by adjuvant injection (adjuvant-induced arthritis [AIA] model) and scored for inflammation. At necropsy, the rear paws were either fixed in formalin and assigned a histologic score (based on synovial cell proliferation, cartilage erosion, bone erosion, and fibroproliferative pannus) or frozen, cryosectioned, and assayed for enzyme activity either by in situ cytochemical staining with a post-azo-coupling method using a chromogenic substrate (Z-arg-arg-MNA) or by a novel assay placing the tissue section directly in a cuvette using the fluorogenic substrate Z-arg-arg-AMC. RESULTS: Enzymatic activity, measured either in frozen sections in situ or in the cuvette assay, was positively correlated with joint destruction (r = 0.7) and inflammation (r = 0.8). Activity was not inhibited significantly by Pefabloc (a serine protease inhibitor), EDTA (a metalloprotease inhibitor), or pepstatin A (an aspartyl protease inhibitor) but was inhibited by E-64 and vinyl sulfone irreversible inhibitors of cysteine proteases. The effect of one of the vinyl sulfone cysteine protease inhibitors, Mu-Leu-HomoPhe-vinylsulfone, was tested in vivo by dietary administration at 2.2 mg/kg/day in the AIA model; this resulted in a significant decrease in inflammation and in the amount of cysteine protease activity measured in the joint tissue. CONCLUSION: Cysteine protease activity levels increase in the diseased state and may be an important target for designing small molecule inhibitors to reduce the inflammation and tissue destruction associated with RA.

Animals↗