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ID PMID Title PublicationDate abstract
21290129 Resolution of adalimumab-induced psoriasis after vitamin D deficiency treatment. 2012 May Tumoral necrosis factor alpha blockers are very efficient in the treatment of many inflammatory systemic diseases, including rheumatoid arthritis and psoriasis. However, a paradoxical arouse of psoriasiform lesions may occur in a few patients taking anti-TNFα. The etiology of this rare side effect is still a mystery, and its treatment may be difficult. The authors report the resolution of adalimumab-induced psoriasis in a woman with rheumatoid arthritis after the use of high vitamin D(3) doses for the treatment of vitamin D deficiency. This is the first report of resolution of anti-TNFα-induced psoriasiform lesions by high doses of vitamin D(3) in a patient with rheumatoid arthritis and vitamin D deficiency. This case raises interesting questions on the role of vitamin D deficiency in the pathogenesis of this side effect and on the possible usefulness of high-dose vitamin D(3) in its treatment.
21028952 Triamcinolone-loaded glutaraldehyde cross-linked chitosan microspheres: prolonged release 2011 Apr The use of glucocorticoids in the treatment of rheumatoid arthritis has been widely employed, but, owing to their systemic side-effects and also their susceptibility to the first pass metabolism, their use is being discouraged. To circumvent this, triamcinolone (TA) were encapsulated in chitosan microspheres with glutaraldehyde as the cross-linking agent to achieve a prolonged drug release. The percentage of drug loading, encapsulation efficiency, and surface morphology by Scanning electron microscopy (SEM), Phase transition by Differential scanning colorimetry (DSC), as well as Fourier transform infrared spectroscopy (FTIR) studies was carried out to characterize the chitosan microspheres. In-vitro and in-vivo release studies revealed that microspheres were able to control the release of TA with a uniform release pattern up to a period of 36 days and thereafter an extended release up to 63 days. The clinical parameters were investigated for changes in paw volume, hematological parameters like Erythrocyte sedimentation rate (ESR), Paced cell volume (PCV), Total leucocyte count (TLC), Hb, and Differential cell count (DCC) in Fruend's complete adjuvant induced arthritic rats. Histopathological findings as well as radiology (X-ray) further confirmed the effectiveness of TA encapsulated microspheres in mitigating the rat arthritic model.
20219013 Microparticles stimulate angiogenesis by inducing ELR(+) CXC-chemokines in synovial fibrob 2011 Apr Microparticles (MPs) are small membrane-vesicles that accumulate in the synovial fluids of patients with rheumatoid arthritis (RA). In the arthritic joints, MPs induce a pro-inflammatory and invasive phenotype in synovial fibroblasts (SFs). The present study investigated whether activation of SFs by MPs stimulates angiogenesis in the inflamed joints of patients with RA. MPs were isolated from Jurkat cells and U937 cells by differential centrifugation. SFs were co-cultured with increasing numbers of MPs. The effects of supernatants from co-cultures on endothelial cells were studied in vitro and in vivo using MTT assays, annexin V and propidium iodide staining, trans-well migration assays and modified matrigel pouch assays. MPs strongly induced the expression of the pro-angiogenic ELR⁺ chemokines CXCL1, CXCL2, CXCL3, CXCL5 and CXCL6 in RASFs. Other vascular growth factors were not induced. Supernatants from co-cultures enhanced the migration of endothelial cells, which could be blocked by neutralizing antibodies against ELR⁺ chemokines. Consistent with the specific induction of ELR⁺ chemokines, proliferation and viability of endothelial cells were not affected by the supernatants. In the in vivo bio-chamber assay, supernatants from RASFs co-cultured with MPs stimulated angiogenesis with a significant increase of vessels infiltrating into the matrigel chamber. We demonstrated that MPs activate RASFs to release pro-angiogenic ELR⁺ chemokines. These pro-angiogenic mediators enhance migration of endothelial cells and stimulate the formation of new vessels. Our data suggest that MPs may contribute to the hypervascularization of inflamed joints in patients with rheumatoid arthritis.
22076134 Prediction of disease and phenotype associations from genome-wide association studies. 2011 BACKGROUND: Genome wide association studies (GWAS) have proven useful as a method for identifying genetic variations associated with diseases. In this study, we analyzed GWAS data for 61 diseases and phenotypes to elucidate common associations based on single nucleotide polymorphisms (SNP). The study was an expansion on a previous study on identifying disease associations via data from a single GWAS on seven diseases. METHODOLOGY/PRINCIPAL FINDINGS: Adjustments to the originally reported study included expansion of the SNP dataset using Linkage Disequilibrium (LD) and refinement of the four levels of analysis to encompass SNP, SNP block, gene, and pathway level comparisons. A pair-wise comparison between diseases and phenotypes was performed at each level and the Jaccard similarity index was used to measure the degree of association between two diseases/phenotypes. Disease relatedness networks (DRNs) were used to visualize our results. We saw predominant relatedness between Multiple Sclerosis, type 1 diabetes, and rheumatoid arthritis for the first three levels of analysis. Expected relatedness was also seen between lipid- and blood-related traits. CONCLUSIONS/SIGNIFICANCE: The predominant associations between Multiple Sclerosis, type 1 diabetes, and rheumatoid arthritis can be validated by clinical studies. The diseases have been proposed to share a systemic inflammation phenotype that can result in progression of additional diseases in patients with one of these three diseases. We also noticed unexpected relationships between metabolic and neurological diseases at the pathway comparison level. The less significant relationships found between diseases require a more detailed literature review to determine validity of the predictions. The results from this study serve as a first step towards a better understanding of seemingly unrelated diseases and phenotypes with similar symptoms or modes of treatment.
21978430 HLA-DRB1 shared epitope genotyping using the revised classification and its association wi 2011 INTRODUCTION: The revised shared epitope (SE) concept in rheumatoid arthritis (RA) is based on the presence (S) or absence (X) of the SE RAA amino acid motif at positions 72 to 74 of the third hypervariable region of the various human leucocyte antigen (HLA)-DRB1 alleles. The purpose of this study was to investigate SE subtypes on the basis of the American College of Rheumatology 1987 revised criteria for the classification of RA in a cohort of South African RA patients (n = 143) and their association with clinical and circulating biomarkers of disease activity (autoantibodies, acute phase reactants and cytokines). METHODS: Genomic DNA was analysed using high-resolution recombinant sequence-specific oligonucleotide PCR typing of the HLA-DRB1 allele. Subtypes of the SE were classified according to the amino acids at positions 72 to 74 for the RAA sequence, and further sub-divided according to the amino acids at positions 70 and 71, which either contribute to (S2, S3P), or negate (S1, S3D) RA susceptibility. Disease activity was assessed on the basis of (1) Disease Activity Score in 28 joints using C-reactive protein (CRP), (2) rheumatoid factor (RF), (3) CRP and (4) serum amyloid A by nephelometry, anticyclic citrullinated peptide antibodies (aCCP) by an immunofluorometric procedure, and cytokines by multiplex bead array technology. RESULTS: Of the 143 RA patients, 81 (57%) were homozygous (SS) and 50 (35%) were heterozygous (SX) for the SE alleles with significant overexpression of S2 and S3P (respective odds ratios (ORs) 5.3 and 5.8; P < 0.0001), and 12 (8%) were classified as no SE allele (XX). Both the SS and SX groups showed a strong association with aCCP positivity (OR = 10.2 and P = 0.0010, OR = 9.2 and P = 0.0028, respectively) relative to the XX group. Clinical scores and concentrations of the other biomarkers of disease activity (RF, CRP and T helper cell type 1 (Th1), Th2, macrophage and fibroblast cytokines) were also generally higher in the SS group than in the SX and XX groups. CONCLUSIONS: RA susceptibility alleles investigated according to revised criteria for the classification of RA were significantly increased in South African RA patients and strongly associated with aCCP in particular as well as with circulating cytokines and disease severity.
20349236 Programmed initiation of hemodialysis for systemic amyloidosis patients associated with rh 2011 Sep Reactive amyloidosis is a serious systemic disease in rheumatoid arthritis (RA). Amyloid protein can be deposited in kidneys, heart or gastrointestinal tract leading to organ failure. Renal involvement is a well-known complication in amyloidosis as this may culminate in end-stage renal disease (ESRD). Hemodialysis (HD) is always considered the treatment of choice for such patients; however, the prognosis is usually poor due to a large number of sudden deaths immediately following HD therapy. To circumvent the problem of HD initiation while instituting HD safety, we devised a plan to start HD and compare patient's survival with our previous data. Sixty-three patients were treated with HD. They were categorized according to the initiation of first dialysis. All patients were divided into planned, unplanned and programmed initiation groups. First dialysis that had been initiated as not urgent was considered 'planned' (20 patients). First dialysis that had been performed urgently for life-threatening renal insufficiency was considered 'unplanned' (31 patients). First dialysis that had been initiated as not urgent and according to our dialysis program was considered 'programmed' (12 patients). Survival of these 63 patients from the initiation of HD at 38 days was 75%, at 321 days was 50% and at 1,784 days was 25%. Patients with unplanned initiation of HD showed a significant poor survival compared with those of both planned and programmed initiation. Additionally, patients with planned and programmed initiation of HD showed no significant difference for the patients' survival. Our study demonstrates that patients with amyloidosis have a higher mortality rate. Nevertheless, programmed initiation of HD will improve the prognosis of patients with ESRD. Such possibility needs to be considered in more detail in the future.
21229375 Disease activity score 28 may overestimate the remission induction of rheumatoid arthritis 2011 Aug We evaluated the efficacy of tocilizumab (TCZ) in patients with rheumatoid arthritis (RA) by the clinical disease activity index (CDAI) and disease activity score (DAS) 28-erythrocyte sedimentation rate (ESR). Thirty-two RA patients received 8 mg/kg of TCZ intravenously every 4 weeks for 48 weeks. The therapeutic response was also evaluated in 30 RA patients treated with 3 mg/kg of infliximab (IFX) for 46 weeks. We compared the therapeutic course of TCZ with IFX in order to evaluate the efficacy of TCZ therapy. A strong positive correlation between CDAI and DAS28-ESR was observed at baseline, whereas their associations dropped significantly within the first 2 months. The association recovered to the baseline by IFX, but still remained low in TCZ. Although a decrement of DAS28-ESR was prominent in TCZ as compared with IFX, that of CDAI was significant in the early phase and even in the latter in patients treated by IFX. The present study revealed that DAS28-ESR may not be sufficient to estimate RA disease activity treated by TCZ, probably due to the significant effect toward inhibition of acute phase reactants by TCZ. CDAI is suggested to be an important alternate of composite measure in these cases.
21091097 Injection-site burning and stinging in patients with rheumatoid arthritis using injectable 2011 Jan OBJECTIVE: Some patients with rheumatoid arthritis (RA) who receive injectable biologics experience injection-site burning and stinging (ISBS); however, the prevalence of ISBS in the general RA population is unknown and may impact preference for an injectable biologic. This study assessed the prevalence of ISBS and associated comorbidities in patients with RA who receive injectable biologics. RESEARCH DESIGN AND METHODS: The physician and patient survey consisted of a retrospective chart review and a prospective assessment. In the former, each participating US rheumatologist reviewed the medical records of five randomly selected RA patients receiving an injectable biologic. In the prospective assessment, each rheumatologist was asked to report data based on interviews with up to 50 RA patients currently treated with an injectable biologic, who were asked whether they had ISBS during or after their most recent injection. RESULTS: Data were analyzed for 504 patients in the retrospective chart review and 3326 patients in the prospective assessment; data were provided by 101 physicians. The overall prevalence of ISBS was 17% and 58% in the retrospective chart review and prospective analyses, respectively. Out of the 1939 prospectively assessed patients who experienced at least some ISBS, 429 (22%) rated the level of ISBS as moderate to severe (13% of total). Increased risk of ISBS was associated with female gender, fibromyalgia, depression, and more severe RA. CONCLUSIONS: The prevalence of ISBS is likely underestimated in many rheumatology practices. Specifically asking about it may identify patients who experience this side effect, provide a more accurate understanding of how significantly it affects them, and provide an opportunity for intervention in light of their preferences.
20683740 Autoantibodies for gastrointestinal organ-specific autoimmune diseases in rheumatoid arthr 2011 Jan BACKGROUND: Clustering of autoimmune diseases is common and may be due to genetic background and exposition to environmental triggers. OBJECTIVE: The aim is to carry out a laboratory and clinical study of the prevalence of gastrointestinal organ-specific autoantibodies in rheumatoid arthritis (RA) patients and their relatives. METHODS: Serum samples of 156 RA patients, 200 relatives, and 100 healthy controls were studied for anti-smooth muscle antibody (ASMA), anti-mitochondrial (AMA), anti-parietal cell (APCA), anti-liver-kidney microsome (LKM), and anti-endomysium antibodies (IgA-EmA) by indirect immunofluorescence. RESULTS: A total of eight out of the 156 (5.1%) RA patients were positive for the autoantibodies (ASMA = 1; AMA = 2, APCA = 5). In the relative group, 12/200 (6%) had at least one positive autoantibody (ASMA = 1; AMA = 2, APCA = 7, IgA-EmA = 2). In the control group, two out of the 100 (2%) healthy controls were positive (ASMA = 1, APCA = 1). No statistical difference was found between RA patients, their relatives, and controls in relation to the frequency of autoantibodies evaluated. CONCLUSION: Although RA patients and their relatives have positivity of AMA, ASMA, and APCA without statistical difference in relation to healthy individuals, the findings may be of value for adequate clinical approach of these subjects.
22581277 Association between metabolic syndrome, BMI, and serum vitamin D concentrations in rheumat 2012 Aug Rheumatoid arthritis (RA) is the most common autoimmune arthritis. The impact of chronic inflammation on atherosclerosis and insulin resistance has been observed in several autoimmune diseases. On the other hand, metabolic syndrome (MetS); a cluster of traditional risk factors for atherosclerosis and diabetes seems to be prevalent in RA patients. It is reasonable to think that protective factors against inflammation can protect patients against atherosclerosis and diabetes, too. Vitamin D (Vit D), a novel immunomodulator, is recently considered to play a protective role against cardiovascular diseases, insulin resistance, and obesity. This cross-sectional study was designed to evaluate the impact of serum Vit D on MetS and body mass index (BMI). One hundred twenty RA patients were enrolled. MetS was assessed according to Adult Treatment Panel III criteria. All patients with known confounders influencing Vit D serum levels were excluded. Serum value of 25-hydroxyvitamin D (25(OH)D) was measured using a commercial ELISA kit. Data were analyzed by SPSS software. A logistic regression analysis stated that prednisolone dosage [p = 0.028, β = 0.177, odds ratio (OR) = 1.194, confidence interval (CI, 1.09-1.32)], age [p = 0.002, β = 0.146, OR = 1.57, CI (1.05-1.27)] and Vit D serum levels [p = 0.049, β = -3.766, OR = 0.023, CI (0.001-0.978)] are all significant predictors of MetS occurrence in RA patients. It was shown that 25(OH)D is a protective factor against MetS. It was also shown that there is a negative correlation between BMI and 25(OH)D serum levels (P = 0.037, r (s) = -0.266). In summary, this study suggested that 25(OH)D plays a protective role against MetS in RA patients. However, this cross-sectional study did not permit a power calculation on the causal relationship between Vit D and metabolic syndrome. On the other hand, Vit D has a negative correlation with BMI in these patients.
22275313 Dual-specificity phosphatase 1-null mice exhibit spontaneous osteolytic disease and enhanc 2012 Jul OBJECTIVE: Bone formation and destruction are usually tightly linked; however, in disorders such as rheumatoid arthritis, periodontal disease, and osteoporosis, elevated osteoclast activity leads to bone destruction. Osteoclast formation and activation are controlled by many signaling pathways, including p38 MAPK. Dual-specificity phosphatase 1 (DUSP-1) is a factor involved in the negative regulation of p38 MAPK. The purpose of this study was to examine the effect of Dusp1 deficiency on bone destruction. METHODS: Penetrance, onset, and severity of collagen-induced arthritis were recorded in DUSP-1+/+ and DUSP-1-/- mice. Bone destruction was assessed by histologic and micro-computed tomographic examination of the joints. The in vitro formation and activation of osteoclasts from DUSP-1+/+ and DUSP-1-/- precursors were assessed in the absence or presence of tumor necrosis factor (TNF). RESULTS: The formation and activation of osteoclasts in vitro in the presence of TNF were enhanced by Dusp1 gene disruption. DUSP-1-/- mice exhibited higher penetrance, earlier onset, and increased severity of experimental arthritis, accompanied by greater numbers of osteoclasts in inflamed joints and more extensive loss of bone. A DUSP-1-/- mouse colony of mixed genetic background also demonstrated striking spontaneous osteolytic destruction of distal phalanges. CONCLUSION: DUSP-1 is a critical regulator of osteoclast activity and limits bone destruction in an experimental model of rheumatoid arthritis. Defects in the expression or activity of DUSP1 in humans may correlate with a propensity to develop osteolytic lesions in arthritis.
22547695 Cyr61 induces IL-6 production by fibroblast-like synoviocytes promoting Th17 differentiati 2012 Jun 1 Cysteine-rich protein 61 (Cyr61)/CCN1 is a product of an immediate early gene and functions in mediating cell adhesion and inducing cell migration. We previously showed that increased production of Cyr61 by fibroblast-like synoviocytes (FLS) in rheumatoid arthritis (RA) promotes FLS proliferation and participates in RA pathogenesis with the IL-17-dependent pathway. However, whether Cyr61 in turn regulates Th17 cell differentiation and further enhances inflammation of RA remained unknown. In the current study, we explored the potential role of Cyr61 as a proinflammatory factor in RA pathogenesis. We found that Cyr61 treatment dramatically induced IL-6 production in FLS isolated from RA patients. Moreover, IL-6 production was attenuated by Cyr61 knockdown in FLS. Mechanistically, we showed that Cyr61 activated IL-6 production via the αvβ5/Akt/NF-κB signaling pathway. Further, using a coculture system consisting of purified CD4(+) T cells and RA FLS, we found that RA FLS stimulated Th17 differentiation, and the pro-Th17 differentiation effect of RA FLS can be attenuated or stimulated by Cyr61 RNA interference or addition of exogenous Cyr61, respectively. Finally, using the collagen-induced arthritis animal model, we showed that treatment with the anti-Cyr61 mAb led to reduction of IL-6 levels, decrease of Th17 response, and attenuation of inflammation and disease progression in vivo. Taken together, our results reveal a novel role of Cyr61 in promoting Th17 development in RA via upregulation of IL-6 production by FLS, thus adding a new layer into the functional interplay between FLS and Th17 in RA pathogenesis. Our study also suggests that targeting of Cyr61 may represent a novel strategy in RA treatment.
22068355 Angiogenic growth factors in rheumatoid arthritis. 2013 Feb We investigated whether the angiogenic profile, which is based on the local expression and systemic levels of angiogenic growth factors (VEGF, Ang-1, Ang-2, and the corresponding receptors), differs between rheumatoid arthritis (RA) and osteoarthritis (OA) patients. We determined the expression of VEGF, Ang-1, and Ang-2 together with its receptors (VEGFR-1/-2 and Tie2) in synovium tissue (ST) and muscular tissue (MT) from patients with RA and OA using quantitative PCR. Tissue samples were obtained from 15 RA and 19 OA patients during total knee arthroplasty. Control MT samples (n = 10) were obtained during spinal surgery. Results are correlated to VEGF and angiopoietin serum levels via ELISA measurements. The VEGF expressions in ST and serum levels were significantly higher in RA patients than in OA patients (P < 0.05). Furthermore, the VEGFR-1 and VEGFR-2 expression in ST from RA patients were significantly higher than in OA patients (P < 0.001 and P < 0.05). The relative concentration of angiopoietins (Ang-1/Ang-2 ratio) was significantly increased in RA (P < 0.01). Serum levels for Ang-2 showed no significant differences. Statistical analysis showed a significant higher level of Tie2 in RA patients (P < 0.001). Analysis of local levels of VEGF, VEGFR-1, VEGFR-2, Ang-1, Ang-2, and Tie2 in the muscular tissue showed no significant difference between RA and OA patients. These results underline the importance of pro-angiogenic growth factor levels for RA corroborating the assumption that VEGF and angiopoietins play an important role in the pathogenesis of RA.
22121133 Mitochondrial mutagenesis correlates with the local inflammatory environment in arthritis. 2012 Apr BACKGROUND: To examine the association between mitochondrial mutagenesis and the proinflammatory microenvironment in patients with inflammatory arthritis. METHODS: Fifty patients with inflammatory arthritis underwent arthroscopy and synovial tissue biopsies, synovial fluid and clinical assessment were obtained. Fifteen patients pre/post-TNFi therapy were also recruited. Normal synovial biopsies were obtained from 10 subjects undergoing interventional arthroscopy. Macroscopic synovitis/vascularity was measured by visual analogue scale. Cell-specific markers CD3 (T cells) and CD68 (macrophages) were quantified by immunohistology. TNFα, IL-6, IFNγ and IL-1β were measured in synovial fluids by MSD multiplex assays. Synovial tissue mitochondrial mutagenesis was quantified using a mitochondrial random mutation capture assay (RMCA). The direct effect of TNFα on oxidative stress and mitochondrial function was assessed in primary cultures of rheumatoid arthritis synovial fibroblast cells (RASFCs). Mitochondrial mutagenesis, reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and mitochondrial mass (MM) were quantified using the RMCA and specific cell fluorescent probes. RESULTS: A significant increase in mtDNA mutation frequency was demonstrated in inflamed synovial tissue compared with control (p<0.05), an effect that was independent of age. mtDNA mutations positively correlated with macroscopic synovitis (r=0.52, p<0.016), vascularity (r=0.54, p<0.01) and with synovial fluid cytokine levels of TNFα (r=0.74, p<0.024) and IFNγ (r=0.72, p<0.039). mtDNA mutation frequency post-TNFi therapy was significantly lower in patients with a DAS<3.2 (p<0.05) and associated with clinical and microscopic measures of disease (p<0.05). In vitro TNFα significantly induced mtDNA mutations, ROS, MM and MMP in RASFCs (all p<0.05). CONCLUSION: High mitochondrial mutations are strongly associated with synovial inflammation showing a direct link between mitochondrial mutations and key proinflammatory pathways.
21952975 What is the ability of anti-cyclic citrullinated peptide antibodies determination in synov 2012 Feb Anti-cyclic citrullinated peptide antibodies (ACPA) seem to be produced locally at the site of joints inflammation in the first stage of rheumatoid arthritis (RA). A strong correlation between serum ACPA and ACPA in the synovial fluid (SF-ACPA) is now suggested. A case-control study was conducted to evaluate the usefulness of ACPA determination in SF of patients with RA. A total of 53 patients with a knee-joint effusion (26 RA, 18 peripheral spondyloarthropathies (SPA), and 9 osteoarthritis (OA)) were included in our study. SF samples were obtained by performing therapeutic arthrosynthesis. IgG serum ACPA and SF-ACPA levels were determined by the enzyme-linked immunosorbent assay (ELISA). We have also determined IgG levels in serum and SF by nephelometry. Higher levels of IgG ACPA antibodies in SF (p = 0.045) and serum (p = 0.045) were found in patients with RA with respect to SPA and OA patients. The Spearman correlation analysis showed a significant and positive correlation between ACPA in serum and SF (rho = 0.516; p = 0.007) not only in the RA group but also in patients with SPA. Serum ACPA discriminated RA from non-RA at a cut-off value of 2.7 U/ml (sensitivity, 69%; specificity, 78%; and area under the curve (AUC), 0.72), whereas SF-ACPA discriminated RA from non-RA at a higher cut-off value of 4.95 U/ml (sensitivity, 73%; specificity, 61%; and AUC, 0.71). Our study suggests that the determination of SF-ACPA give complement information to serum ACPA in patients with RA.
22245418 Differential protein profiling of synovial fluid from rheumatoid arthritis and osteoarthri 2012 Jun 6 The purpose of this study was to identify those proteins relatively more abundant in the synovial fluid (SF) of patients suffering from rheumatoid arthritis (RA) and osteoarthritis (OA) using high performance liquid chromatography coupled to mass spectrometry. 20 individual SF samples from each disease were pooled into two groups (RA and OA) to reduce the contribution of extreme individual values. Prior to the proteomic analysis, samples were immunodepleted from the top 20 most abundant plasma proteins, to enrich the lower-abundance protein fractions. Then, they were subjected to protein size fractioning and in-gel digestion, followed by reversed-phase peptide separation in a nano-LC system and subsequent peptide identification by MALDI-TOF/TOF. This strategy led to the identification of 136 different proteins in SF, which is the largest number of SF proteins described up to date by proteomics. A relative quantification of the proteins between RA and OA was carried out by spectral counting analysis. In RA, our results show a greater relative abundance of proteins related to complement activation, inflammation and the immune response, such as the major matrix metalloproteinases and several neutrophil-related proteins. In OA, we detected an increase in proteins involved in the formation and remodeling of the extracellular matrix (ECM), such as fibronectin, kininogen-1, cartilage acidic protein 1 and cartilage oligomeric matrix protein. The results obtained for MMP-1, BGH3, fibronectin and gelsolin were verified by immunoblotting analyses. Some of the novel proteins identified in this work might be relevant not only for increasing knowledge on the etiopathogenesis of RA and OA processes, but also as putative disease biomarkers, as their presence in SF is a prior step to their dilution in serum. This article is part of a Special Issue entitled: Proteomics: The clinical link.
22011399 Toll-like receptor 4 gene polymorphisms in polymyalgia rheumatica and elderly-onset rheuma 2011 Sep OBJECTIVES: Coding variants in TLR4 gene have been reported to be associated with inflammatory diseases. The aim of this study was to determine whether two of these polymorphisms (Asp299Gly and Thr399Ile) of TLR4 contribute to the genetic background of polymyalgia rheumatica (PMR) and elderly-onset rheumatoid arthritis (EORA). Furthermore, we have attempted to correlate the functional consequences of these polymorphisms. METHODS: 164 patients with PMR, 93 with EORA and 126 unrelated age-matched controls were genotyped. The TLR4 genotypes were determined using allele-specific primers and restriction fragment length polymorphism analysis. Association of genotypes and alleles with disease susceptibility and disease phenotypes were studied. TLR4 expression was assessed on PBMCs by flow cytometry and TLR4 function was assessed by stimulating PBMCs in vitro with LPS. RESULTS: No significant difference in allele frequency or genotype between patients with elderly-onset inflammatory conditions and controls was observed. The Thr399Ile CC genotype was associated with a higher cumulative dose of corticosteroids in patients with PMR (p=0.031). We found no association with TLR4 expression on B cells, T cells or monocytes or a distinct phenotype of TLR4 response with the Asp299Gly or Thr399Ile genotypes. CONCLUSIONS: These results do not support the association of these TLR4 variants with two age-related inflammatory conditions. The value of determining Thr399Ile genotypes for disease prognosis in PMR should be confirmed in different populations.
22128899 Association study of CARD8 (p.C10X) and NLRP3 (p.Q705K) variants with rheumatoid arthritis 2012 Apr The objective of the study was to investigate the association of caspase activating and recruitment domain 8 (CARD8) and nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain containing 3 (NLRP3) polymorphisms with rheumatoid arthritis (RA) in Tunisian and French populations. CARD8 (c.30T>A, rs2043211) and NLRP3 (c.2113C>A, rs35829419) single nucleotide polymorphisms (SNPs) were genotyped in 100 French RA trio families and 141 Tunisian patients with RA and 191 unrelated healthy controls, using TaqMan(®) allelic discrimination assay. The genetic analyses for the association and linkage in French families were performed using the comparison of allelic frequencies (AFBAC), the genotype relative risk (GRR) and the transmission disequilibrium test (TDT). Data for case and control samples were analysed by chi-square-test, GRR and odds ratio (OR). No significant differences between alleles and genotypes frequencies were detected in French trio and Tunisian patients with RA and controls, either with CARD8 or with NLRP3 SNPs both in French and in Tunisian populations. Moreover, stratifying patients according to the presence of rheumatoid factor (RF), anti-cyclic peptides antibodies (ACPA), erosion, nodules, other autoimmune disease or HLA-DRB1*04-positive subgroups did not show any significant association with CARD8 or NLRP3 (P ≥ 0.05). This study suggests that variations in the innate immunity genes CARD8 (p.C10X) and NLRP3 (p.Q705K) have no effect on RA susceptibility either in the Tunisian or in the French population.
22704227 Patellar fracture after total knee arthroplasty for rheumatoid arthritis. 2013 Jan Patellar fracture is one of the most challenging complications of total knee arthroplasty, but relatively, little is known about it in patients with rheumatoid arthritis. We retrospectively analyzed 329 total knee arthroplasties performed in 230 female patients with rheumatoid arthritis to identify the incidence and risk factors for postoperative patellar fractures. The mean age was 61.8 years, and the mean follow-up period was 6.2 years. Patellar resurfacing was performed in all cases. Five postoperative patellar fractures (1.51%) were identified, and a thin residual patellar thickness and the use of posterior-stabilizing components were identified as significant risk factors, although the number of fractures was small in both groups. There was also tendency of higher age and greater joint line change observed in patients with fracture compared with those without fracture.
21261568 Diurnal variation of connective tissue metabolites in early and long-standing rheumatoid a 2011 Mar OBJECTIVE: To study the circadian variability of circulating connective tissue metabolites in patients with very early (VERA) and long-standing rheumatoid arthritis (LRA) and in healthy control individuals. METHODS: Eleven patients with newly diagnosed, untreated RA, disease duration < 6 months, and 10 patients with LRA were included, together with 16 healthy control subjects. Seven blood samples were drawn serially from each participant at 3-hourly intervals from 10.00-22.00 h, fasting at 07.00 h the following day and finally at 10.00 h. Cartilage oligomeric matrix protein (COMP) and hyaluronan (HYA) were quantified by enzyme-linked immunosorbent assay (ELISA) and the N-terminal propeptide of collagen type III (PIIINP) was determined by radioimmunoassay (RIA). RESULTS: The two RA subsets did not differ with respect to age, gender distribution, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), immunoglobulin M rheumatoid factor (IgM-RF) status, global health status and pain. Healthy controls were younger than both VERA and LRA patients. At baseline, PIIINP, HYA, and COMP were increased significantly in both RA cohorts compared with controls. No circadian rhythmicity was recorded with respect to HYA and PIIINP. By contrast, COMP was decreased at 07.00 h in all three study groups; this decline was particularly prominent in LRA. CONCLUSION: Within-day changes of PIIINP, HYA, and COMP are qualitatively similar in RA at different stages and in healthy individuals, indicating that the connective tissue responses to rhythmic physiological signals are not abolished by disease-modifying anti-rheumatic drug (DMARD) therapy. Serum for measurement of HYA and COMP should be collected between 10.00 and 20.00 h.