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ID PMID Title PublicationDate abstract
20171050 Changes in cobalt and chromium levels after metal-on-metal hip resurfacing in young, activ 2011 Jan Metal-on-metal resurfacing arthroplasty is increasingly being performed in young, active patients. Serum and urine metal ion levels are monitored in these patients to assess the physiologic effects of metal-on-metal wear on them. The aim of our prospective study was to evaluate the serum and urine levels of cobalt (Co) and chromium (Cr) in young (age, ≤50 years), active Chinese patients who had undergone metal-on-metal hybrid resurfacing arthroplasties. Levels were measured preoperatively using atomic absorption spectrometry and then sequentially at 3, 6, 9, 12, and 24 months after surgery. For both serum and urine Co and Cr, there was an initial increase to a peak at 6 months, followed by a gradual decline after 6 months, whereas renal function was normal during the study the 2-year study period. There was no radiographic evidence of component loosening. All implants were functioning well. Further long-term studies are needed to observe clinical outcomes and to determine the physiologic effects of the wearing process.
20022453 Metal-on-metal cups cemented into reinforcement rings: a possible new acetabular reconstru 2011 Jan The purpose of this study was to evaluate the clinical and radiological results of Metasul cups cemented into reinforcement rings for young and active patients. Twenty-three total hip arthroplasties with Metasul cups were cemented into Muller reinforcement rings. Mean follow-up was 6.1 years (5-10). At final follow-up, the Harris hip score increased from 62.2 (39-85) to 95.2 (84-100, P = .01): no revision was undertaken for aseptic loosening or fixation failure. Considering reoperation and bearing revision as end points, survival rates were 95.8% and 100%, respectively. The mean blood concentrations of chromium, cobalt, and titanium were 1.85 μg/L, 1.24 μg/L, and 9.62 μg/L, respectively. A longer follow-up is mandatory, but it seems possible to use hard-on-hard bearings with metallic rings in young patients during hip revisions or in dysplastic cases with encouraging intermediate follow-up results.
21366559 Indoleamine 2,3-dioxygenase-expressing peripheral cells in rheumatoid arthritis and system 2011 Oct BACKGROUND: Indoleamine 2,3-dioxygenase (IDO) is a tryptophan-degrading enzyme which suppresses T lymphocyte activity and induces Foxp3+ CD4+ regulatory T cells (Tregs) polarisation. The aim of this study was to evaluate the expression of IDO in freshly isolated peripheral cells as well as to enumerate Tregs and Th17 subpopulation in rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) patients. MATERIALS AND METHODS: The percentage of IDO-expressing cells as well as Tregs and Th17 was evaluated in 14 active RA- (aRA), 13 inactive RA- (iRA), 7 aSLE-, 12 iSLE-treated patients and 11 healthy donors (controls). Intracellular IDO was analysed by flow cytometry in CD14+, CD8α+, CD16+ and CD123+ cell subpopulations. Tregs and Th17 were assessed by intracellular of Foxp3 and IL17A detection in CD4+ CD14- cells. A total of 50,000 events were recorded for each sample. RESULTS: The amounts of CD14+/CD16-/IDO+, CD14-/CD16+/IDO+ and CD14+/CD16+/IDO+-expressing peripheral cells were slightly lower in inactive vs. active disease in RA and SLE patients. Notwithstanding, only inactive patients had statistically significant lower percentages when compared to controls. aRA and iRA showed a statistically significant decrease in CD8α+/CD123+/IDO+ vs. controls. Meanwhile, only iSLE patients had lower CD8α+/CD123+/IDO+ cells vs. aSLE patients and controls. Th17 subset was present in higher amounts in aRA and iRA patients vs. controls. Tregs showed an increase in aRA patients vs. controls. CONCLUSIONS: A decreased percentage of IDO-expressing peripheral cells were determined in iRA and iSLE compared to controls. It could play a critical role in tolerance loss in these diseases.
22205381 The clinical significance of anti-cyclic citrullinated peptide antibody in primary Sjögre 2012 Dec Anti-cyclic citrullinated peptide antibody (anti-CCP) is a specific marker for the diagnosis of rheumatoid arthritis. However, this antibody can be detected in other rheumatic diseases and even in healthy people. This study aims to determine the prevalence and the clinical significance of anti-CCP in patients with primary Sjögren syndrome (pSS). We analyzed the clinical and laboratory data of 95 patients with pSS by retrospective review of their medical records. Anti-CCP was measured by ELISA kit. Anti-CCP, rheumatoid factor (RF), anti-nuclear antibody, anti-Ro and anti-La antibodies, and clinical data were investigated. We analyzed clinical and serologic characteristics of anti-CCP-positive patients. Twenty-one patients (22.1%) had positive anti-CCP (mean titer 61.6 ± 15.6 U/ml) and 40 patients (42.1%) had positive RF (mean titer 98.8 ± 22.7 IU/ml). Seventy-nine patients (83.1%) had arthralgia, and 31 patients (32.6%) had non-erosive arthritis on physical examination and radiologic images. Anti-CCP-positive patients had more frequently positive RF (71.4% vs. 41.8%, P = 0.01) and anti-Ro antibody (85.7% vs. 60.8%, P = 0.03). Anti-CCP-positive patients had non-erosive arthritis more frequently than anti-CCP-negative patients (76.1% vs. 21.6%, P < 0.01). The prevalence of anti-CCP was 22.1% in pSS, and anti-CCP was associated with non-erosive arthritis, and positivity of RF and anti-Ro antibody.
22354637 Pneumocystis jirovecii pneumonia associated with etanercept treatment in patients with rhe 2012 Nov OBJECTIVES: The association of anti-tumor necrosis factor therapy with opportunistic infections in rheumatoid arthritis (RA) patients has been reported. The goal of this study was to clarify the clinical characteristics and the risk factors of RA patients who developed Pneumocystis jirovecii pneumonia (PCP) during etanercept therapy. METHODS: We conducted a multicenter, case-control study in which 15 RA patients who developed PCP were compared with 74 RA patients who did not develop PCP during etanercept therapy. RESULTS: PCP developed within 26 weeks following the first injection of etanercept in 86.7% of the patients. All PCP patients presented with a rapid and severe clinical course and the overall mortality was 6.7%. Independent risk factors were identified using multivariate analysis and included age ≥65 years [hazard ratio (HR) 3.35, p = 0.037], coexisting lung disease (HR 4.48, p = 0.009), and concomitant methotrexate treatment (HR 4.68, p = 0.005). In patients having a larger number of risk factors, the cumulative probability of developing PCP was significantly higher (p < 0.001 for patients with two or more risk factors vs. those with no risk factor, and p = 0.001 for patients with one risk factor vs. those with no risk factor). CONCLUSION: Physicians must consider the possibility of PCP developing during etanercept therapy in RA patients, particularly if one or more risk factors are present.
22626832 Citrullinated mouse collagen administered to DBA/1J mice in the absence of adjuvant initia 2012 Aug INTRODUCTION: Citrullinated self-proteins are thought to be involved in the onset/progression of rheumatoid arthritis (RA). Numerous studies have been performed to look for the self-antigen that becomes citrullinated and induces RA. Importantly, these studies have been performed using citrullinated self-antigens injected into an animal model in the presence of a strong adjuvant in order to derive the response. However, to date no studies have been performed to determine if these phenotypes can be induced in the absence of an adjuvant. METHODS: To investigate this possibility, mice were immunized with citrullinated or non-citrullinated mouse Type II collagen (Cit-Col or Col) in the presence or absence of Freund's Complete Adjuvant (FCA). RESULTS: An autoimmune-like RA response was observed in mice immunized with Cit-Col in the absence of FCA; by the increase in caliper score, visual observation, and micro-CT analysis of bone erosions. Antibody and T-cell responses were increased in the Cit-Col injected mice to Cit-Col as well as antibody to Anti-Citrullinated Peptide Antigens (ACPA) as determined by a commercially available test kit. CONCLUSIONS: Therefore, the use of citrullinated mouse collagen induces an autoimmune-like RA in the absence of an adjuvant. These data also suggest that citrullinate self-proteins may be potential molecular adjuvants that assist in driving an inflammatory response, that increases the production of PAD in joint tissue, resulting in the citrullination of other self-proteins to exacerbate the disease.
22595227 Enhanced COMP catabolism detected in serum of patients with arthritis and animal disease m 2012 Aug OBJECTIVE: The study aimed determining whether assessment of cartilage oligomeric matrix protein (COMP) degradation products could serve as a serological disease course and therapeutic response predictor in arthritis. METHODS: We generated a panel of monoclonal antibodies against COMP fragments and developed a novel capture enzyme-linked immunosorbent assay (ELISA) for detecting COMP fragments in patients with osteoarthritis (OA) and rheumatoid arthritis (RA). This test was also used to monitor COMP fragments in surgically-induced OA, collagen-induced arthritis (CIA), and tumor necrosis factor (TNF) transgenic animal models. RESULTS: Compared with a commercial COMP ELISA kit that detected no significant difference in COMP levels between OA and control groups, a significant increase of the COMP fragments were noted in the serum of OA patients assayed by this newly established ELISA. In addition, serum COMP fragment levels were well correlated with severity in OA patients and the progression of surgically-induced OA in murine models. Furthermore, the serum levels of COMP fragments in RA patients, mice with CIA, and TNF transgenic mice were significantly higher when compared with their controls. Interestingly, treatment with TNFα inhibitors and methotrexate led to a significant decrease of serum COMP fragments in RA patients. Additionally, administration of Atsttrin [Tang, et al., Science 2011;332(6028):478] also resulted in a significant reduction in COMP fragments in arthritis mice models. CONCLUSION: A novel sandwich ELISA is capable of reproducibly measuring serum COMP fragments in both arthritic patients and rodent arthritis models. This test also provides a valuable means to utilize serum COMP fragments for monitoring the effects of interventions in arthritis.
21572150 Persistence with anti-tumor necrosis factor therapies in patients with rheumatoid arthriti 2011 Jul OBJECTIVE: To evaluate persistence with anti-tumor necrosis factor (TNF) therapy and predictors of discontinuation in patients with rheumatoid arthritis (RA). METHODS: This retrospective analysis used data from RADIUS 1, a 5-year observational registry of patients with RA, to determine time to first- and second-course discontinuation of etanercept, infliximab, and adalimumab. First-course therapy was defined as first exposure to anti-TNF therapy, and second-course therapy was defined as exposure to anti-TNF therapy after the first discontinuation. Kaplan-Meier survival analysis was used to assess persistence, log-rank tests were used to compare therapies, and Cox proportional hazards models were used to assess potential predictors of treatment discontinuation. RESULTS: This analysis included 2418 patients. Mean persistence rates were similar among treatments [first-course: etanercept, 51%; infliximab, 48%; adalimumab, 48% (followup was 54 weeks for etanercept and infliximab and 42 weeks for adalimumab); second-course: 56%, 50%, 46%, respectively (followup was 36 weeks for etanercept and infliximab and 30 weeks for adalimumab)]. Discontinuations of first-course therapy due to ineffectiveness were similar among treatments (etanercept, 19%; infliximab, 19%; adalimumab, 20%) and discontinuations due to adverse events were significantly (p = 0.0006) lower for etanercept than for infliximab (etanercept, 14%; infliximab, 22%; adalimumab, 17%). Predictors from univariable analysis of first- or second-course therapy discontinuation included increased comorbidities (etanercept), female sex (infliximab), Clinical Disease Activity Index > 22 (infliximab), and a Stanford Health Assessment Questionnaire score > 0.5 (adalimumab). CONCLUSION: In this population, first- and second-course persistence was similar among anti-TNF therapies. First-course discontinuation due to adverse events was lower with etanercept compared with infliximab.
21914628 Clinical response and tolerability to abatacept in patients with rheumatoid arthritis prev 2011 Nov OBJECTIVE: To assess the efficacy and safety of abatacept in biological-naive patients with rheumatoid arthritis and an inadequate response to methotrexate treated in the long-term extension (LTE) of the ATTEST trial. METHODS: Patients randomly assigned to abatacept, placebo or infliximab completing the 1-year double-blind period were eligible to receive abatacept ∼10 mg/kg in the open-label LTE. Efficacy to year 2 is presented for patients randomly assigned to abatacept or infliximab who switched to open-label abatacept. Safety data are presented for all patients entering LTE regardless of double-blind treatment. RESULTS: Of 431 patients randomly assigned, 79.8% remained on abatacept at year 2. At years 1 and 2, 19.7% and 26.1% of abatacept and 13.3% and 28.6% of infliximab-to-abatacept patients achieved disease activity score 28-defined remission (<2.6). Safety with abatacept during the cumulative study period was consistent with the double-blind experience, with no increase in adverse event incidence following the switch to abatacept. CONCLUSION: In methotrexate-inadequate responders, abatacept efficacy was maintained over 2 years. For infliximab-to-abatacept patients, efficacy improvements were seen in year 2 after patients switched to abatacept. Switching directly from infliximab to abatacept was well tolerated. These data demonstrate that abatacept provides sustained responses and consistent safety, suggesting that switching from infliximab to abatacept is a viable treatment option.
22139198 Antigen-presenting effects of effector memory Vγ9Vδ2 T cells in rheumatoid arthritis. 2012 May Rheumatoid arthritis is an autoimmune disease that primarily affects the limbs, but the pathogenic mechanism remains unclear. γδ T cells, a T-cell subpopulation, are characterized by multiple biological functions and associated with a variety of diseases. This study investigated the antigen-presenting effects of γδ T cells and their relationship with rheumatoid arthritis development. We found that Vγ9Vδ2 T cells (the predominant subtype of γδ T cells in peripheral blood) were activated by isopentenyl pyrophosphate to continuously proliferate and differentiate into effector memory cells. The effector memory Vγ9Vδ2 T cells exhibited phenotypic characteristics of specific antigen-presenting cells, including high HLA-DR and CD80/86 expression. These Vγ9Vδ2 T cells could present soluble antigens and synthetic peptides to CD4(+) T cells. Vγ9Vδ2 T cells with different phenotypes showed different cytokine secretion patterns. Effector memory Vγ9Vδ2 T cells simultaneously secreted not only interferon (IFN)-γ but also IL-17. The peripheral blood and joint synovial fluid from RA patients contained numerous heterogeneous γδ T cells that were predominantly effector memory Vγ9Vδ2 T cells with the ability to secrete inflammatory factors. We also found that γδ T cells had a similar antigen-presenting capability to B cells. These results suggest that during the development of rheumatoid arthritis, γδ T cells can aggravate immune dysfunction and produce abnormal immune damage by secreting cytokines and inducing inflammatory cells to participate in synergistic inflammatory responses. Furthermore, γδ T cells can behave similarly to B cells to present viral peptides and autoantigen peptides to CD4(+) T cells, thus sustaining CD4(+) T-cell activation.
22459542 Golimumab in patients with active rheumatoid arthritis who have previous experience with t 2012 Oct OBJECTIVE: The aim of this study was to assess long-term golimumab therapy in patients with rheumatoid arthritis (RA) who discontinued previous tumour necrosis factor alpha (TNFα) inhibitor(s) for any reason. METHODS: Results through week 24 of this multicentre, randomised, double-blind, placebo-controlled study of active RA (≥4 tender, ≥4 swollen joints) were previously reported. Patients received placebo (Group 1), 50 mg golimumab (Group 2) or 100 mg golimumab (Group 3) subcutaneous injections every 4 weeks. Patients from Groups 1 and 2 with <20% improvement in tender/swollen joints at week 16 early escaped to golimumab 50 mg and 100 mg, respectively. At week 24, Group 1 patients crossed over to golimumab 50 mg, Group 2 continued golimumab 50/100 mg per escape status and Group 3 maintained dosing. Data through week 160 are reported. RESULTS: 459 of the 461 randomised patients were treated; 236/459 (51%) continued treatment through week 160. From week 24 to week 100, ACR20 (≥20% improvement in American College of Rheumatology criteria) response and ≥0.25 unit HAQ (Health Assessment Questionnaire) improvement were sustained in 70-73% and 75-81% of responding patients, respectively. Overall at week 160, 63%, 67% and 57% of patients achieved ACR20 response and 59%, 65% and 64% had HAQ improvement ≥0.25 unit in Groups 1, 2 and 3, respectively. Adjusted for follow-up duration, adverse event incidences (95% CI) per 100 patient-years among patients treated with golimumab 50 mg and 100 mg were 4.70 (2.63 to 7.75) and 8.07 (6.02 to 10.58) for serious infection, 0.95 (0.20 to 2.77) and 2.04 (1.09 to 3.49) for malignancy and 0.00 (0.00 to 0.94) and 0.62 (0.17 to 1.59) for death, respectively. CONCLUSION: In patients with active RA who discontinued previous TNF-antagonist treatment, golimumab 50 and 100 mg injections every 4 weeks yielded sustained improvements in signs/symptoms and physical function in ∼57-67% of patients who continued treatment. Golimumab safety was consistent with other anti-TNF agents, although definitive conclusions regarding long-term safety require further monitoring.
21998116 Change in the discontinuation pattern of tumour necrosis factor antagonists in rheumatoid 2012 Mar OBJECTIVE: To investigate in rheumatoid arthritis (RA) the rate and reason of discontinuation of tumour necrosis factor (TNF) antagonists over the past decade. METHODS: RA patients in BIOBADASER 2.0 were stratified according to the start date of their first TNF antagonist into 2000-3, 2004-6 and 2007-9 interval years. Cumulative incidence function of discontinuation for inefficacy or toxicity was estimated with the alternative reason as competing risk. Competing risks regression models were used to measure the association of study groups with covariates and reasons for discontinuation. Association is expressed as subhazard ratios (SHR). RESULTS: 2907 RA patients were included in the study. Competing risk regression for inefficacy shows larger SHR for patients starting treatment in 2004-6 (SHR 2.57; 95% CI 1.55 to 4.25) and 2007-9 (SHR 3.4; 95% CI 2.08 to 5.55) than for those starting in 2000-3, after adjusting for TNF antagonists, clinical activity and concomitant treatment. Competing risk regression analysis for adverse events revealed no differences across the three time intervals. CONCLUSIONS: In RA, the discontinuation rate of TNF antagonists in the first year of treatment is higher more recently than a decade ago, inefficacy being the main reason for the increased rate. The rate of discontinuation for adverse events has remained stable.
22205302 Identification of HnRNP-A2/B1 as a target antigen of anti-endothelial cell IgA antibody in 2012 Mar Behçet's disease (BD) is a chronic, multisystemic vasculitis that theoretically affects all sizes and types of blood vessels. Although pathogenesis remains enigmatic, endothelial cells are believed to be the primary target in this disease. We detected the target protein using western blotting and immunoprecipitation and determined the amino-acid sequence of the peptide by liquid chromatography-matrix assisted laser desorption/ionization-tandem time-of-flight analysis (LC-MALDI-TOF/TOF). Serum reactivity against the recombinant target protein was analyzed by immunoblotting. Serum reactivity against streptococcal 65-kD heat shock protein (hsp-65) and the recombinant target protein was investigated by ELISA. The 36-40-kD protein band that was obtained from immunoprecipitation, which was analyzed by LC-MALDI-TOF/TOF, exhibited the amino-acid sequences of heterogeneous nuclear ribonucleoproteins A2/B1 (hnRNP-A2/B1). Reactivity of serum IgA against human recombinant hnRNP-A2/B1 was detected in 25 of 30 BD patients (83.3%), 4 of 30 systemic lupus erythematosus patients (13.3%), 8 of 30 rheumatoid arthritis patients (26.7%), 9 of 30 Takayasu's arteritis patients (30%), 6 of 30 healthy controls (20%), and none of 30 IgA nephropathy patients. Optical densities obtained from ELISAs against the recombinant human hnRNP-A2/B1 were correlated with those against the recombinant streptococcal hsp-65.JID JOURNAL CLUB ARTICLE: For questions, answers, and open discussion about this article, please go to http://www.nature.com/jid/journalclub.
20347257 Association between deep vein thrombosis and the temperature at the popliteal fossa during 2011 Apr The temperature at the popliteal fossa during cement curing and its relationship with deep vein thrombosis (DVT) in total knee arthroplasty (TKA) has not been investigated. Fifty-six consecutive patients who underwent primary TKA were recruited. The temperatures at the popliteal fossa were measured during bone cement exothermic polymerization. Postoperative operated leg ascending venographies were performed 5 days after TKA for screening of DVT. The maximum temperatures were 32.5°C ± 1.0°C at the popliteal fossa during cement curing. No significant difference was found of the maximum temperatures in the popliteal fossa between the non-DVT and DVT groups. The present study indicated that the heat resulting from polymerization of the cement may not be a possible cause of damage to the veins surrounding the knee, and it may have no relationship with DVT.
21567377 Collagen-induced arthritis is exacerbated in C-reactive protein-deficient mice. 2011 Sep OBJECTIVE: Blood C-reactive protein (CRP) is routinely measured to gauge inflammation. In rheumatoid arthritis (RA), a heightened CRP level is predictive of a poor outcome, while a lowered CRP level is indicative of a positive response to therapy. CRP interacts with the innate and adaptive immune systems in ways that suggest it may be causal in RA and, although this is not proven, it is widely assumed that CRP makes a detrimental contribution to the disease process. Paradoxically, results from animal studies have indicated that CRP might be beneficial in RA. This study was undertaken to study the role of CRP in a mouse model of RA, the collagen-induced arthritis (CIA) model. METHODS: We compared the impact of CRP deficiency with that of transgenic overexpression of CRP on inflammatory and immune responses in mice, using CRP-deficient (Crp-/-) and human CRP-transgenic (CRP-Tg) mice, respectively. Susceptibility to CIA, a disease that resembles RA in humans, was compared between wild-type, Crp-/-, and CRP-Tg mice. RESULTS: CRP deficiency significantly altered the inflammatory cytokine response evoked by challenge with endotoxin or anti-CD3 antibody, and heightened some immune responses. Compared to that in wild-type mice, CIA in Crp-/- mice progressed more rapidly and was more severe, whereas CIA in CRP-Tg mice was dramatically attenuated. Despite these disparate clinical outcomes, anticollagen autoantibody responses during CIA did not differ among the genotypes. CONCLUSION: CRP exerts an early and beneficial effect in mice with CIA. The mechanism of this effect remains unknown but does not involve improvement of the autoantibody profile. In humans, the presumed detrimental role of a heightened blood CRP level during active RA might be balanced by a beneficial effect of the baseline CRP (i.e., levels manifest during the preclinical stages of disease).
22286218 Five amino acids in three HLA proteins explain most of the association between MHC and ser 2012 Jan 29 The genetic association of the major histocompatibility complex (MHC) to rheumatoid arthritis risk has commonly been attributed to alleles in HLA-DRB1. However, debate persists about the identity of the causal variants in HLA-DRB1 and the presence of independent effects elsewhere in the MHC. Using existing genome-wide SNP data in 5,018 individuals with seropositive rheumatoid arthritis (cases) and 14,974 unaffected controls, we imputed and tested classical alleles and amino acid polymorphisms in HLA-A, HLA-B, HLA-C, HLA-DPA1, HLA-DPB1, HLA-DQA1, HLA-DQB1 and HLA-DRB1, as well as 3,117 SNPs across the MHC. Conditional and haplotype analyses identified that three amino acid positions (11, 71 and 74) in HLA-DRβ1 and single-amino-acid polymorphisms in HLA-B (at position 9) and HLA-DPβ1 (at position 9), which are all located in peptide-binding grooves, almost completely explain the MHC association to rheumatoid arthritis risk. This study shows how imputation of functional variation from large reference panels can help fine map association signals in the MHC.
21452922 Methotrexate chronotherapy is effective against rheumatoid arthritis. 2011 Apr Methotrexate (MTX) is the most important drug for treating rheumatoid arthritis (RA). It has been stated that cytokines play an important role in the pathogenesis of RA, and that cytokine levels increase and show 24-h rhythms in RA patients. Previously, we found that arthritis was relieved after the administration of MTX at specific times in synchronization with the 24-h rhythm of tumor necrosis factor (TNF)-α in collagen-induced arthritis (CIA) animals. Based on our findings in an earlier study of the dosing time-dependent effects of MTX in MRL/lpr mice, which develop autoimmune disorders that share similarities with human RA, we examined here the utility of MTX chronotherapy in Japanese RA patients. In an initial animal modeling study, we collected blood from MRL/lpr mice at different times (2, 6, 10, 14, 18, or 22 hours after the light was turned on [HALO]), and we measured TNF-α mRNA expression in leukocytes. MTX was administered to the mice at two different dosing times (6 or 18 HALO), and various blood parameters were measured to estimate arthritis activity. TNF-α mRNA levels showed a clear 24-h rhythm with a peak at 22 HALO and a trough at 18 HALO after RA had developed. In these MRL/lpr mice, inflammation and TNF-α were markedly reduced when the MTX dosing time was matched to the time (18 HALO) when the TNF-α level began to increase. We then applied these findings to Japanese RA patients by switching them from the standard MTX three times/wk (day 1: after breakfast and supper; day 2: after breakfast schedule), to chronotherapy, in which the dose and number of doses/wk were not changed but MTX was administered once-a-day at bedtime. Disease Activity Score (DAS)28, modified health assessment questionnaire (MHAQ), and adverse effects were assessed. With MTX chronotherapy, DAS28, which is commonly used to quantitatively assess RA symptoms, was significantly improved at all follow-up clinical visit times compared with the baseline (vs. 1 mo: p = .0197, 2 mos: p = .0107, 3 mos: p = .0087). Significant symptom recovery was observed in 41.2% of patients, and 23.5% of patients achieved clinical remission during the 3 mos of follow-up. Functional capacity of RA patients, as indicated by the MHAQ, was markedly improved by chronotherapy. There were no severe adverse effects. Thus, we demonstrated (i) inflammation and plasma TNF-α concentrations were significantly reduced in MRL/lpr mice treated with MTX at 18 HALO, the time when TNF-α mRNA level began to increase; and (ii) MTX bedtime chronotherapy was safe, markedly reduced disease activity, and improved the functional capacity of RA patients. The findings on RA patients show that bedtime MTX chronotherapy can improve RA symptoms compared to the current standard dosing methods.
22825589 Sex-specific differences in effect size estimates at established complex trait loci. 2012 Oct BACKGROUND: Genetic differences between men and women may contribute to sex differences in prevalence and progression of many common complex diseases. Using the WTCCC GWAS, we analysed whether there are sex-specific differences in effect size estimates at 142 established loci for seven complex diseases: rheumatoid arthritis, type 1 diabetes (T1D), Crohn's disease, type 2 diabetes (T2D), hypertension, coronary artery disease and bipolar disorder. METHODS: For each Single nucleotide polymorphism (SNP), we calculated the per-allele odds ratio for each sex and the relative odds ratios (RORs; the effect size is higher in men with ROR greater than one). RORs were then meta-analysed across loci within each disease and across diseases. RESULTS: For each disease, summary RORs were not different from one, but there was between-SNP heterogeneity in the RORs for T1D and T2D. Four loci in T1D, three in Crohn's disease and three in T2D showed differences in the genetic effect between men and women (P<0.05). We probed these differences in additional independent replication samples for T1D and T2D. The differences remained for the T1D loci CTSH, 17q21 and 20p13 and the T2D locus BCL11A, when WTCCC data and replication data were meta-analysed. Only CTSH showed different genetic effect between men and women in the replication data alone. CONCLUSION: Our results exclude the presence of large and frequent differences in the effect size estimates between men and women for the established loci in the seven common diseases explored. Documenting small differences in genetic effects between men and women requires large studies and systematic evaluation.
23148088 Intron-derived aberrant splicing of A20 transcript in rheumatoid arthritis. 2013 Mar OBJECTIVE: Aberrant splicing is one of the most significant components generating functional diversity in many pathological conditions. The objective of this study was to analyse the mutations or aberrant splicing of A20 transcript, the region encompassing the ovarian tumour (OTU) domain [which is functionally important as an inhibitor of nuclear factor (NF)-κB activation] in fibroblast-like synoviocytes (FLSs) from RA patients. METHODS: Alterations in A20 transcripts were determined through sequence analysis of 10 clones of A20 cDNA in FLSs from each of the five RA patients. The levels of aberrant A20 transcript were measured by quantitative real-time RT-PCR with primers to specifically recognize the inserted introns. The functional role of A20 and its aberrant variants were examined by analysing NF-κB luciferase reporter activity and NF-κB-dependent target gene expression. RESULTS: In RA FLSs, we discovered four novel aberrant A20 transcripts, most of which resulted from insertion of partial intron 2, intron 4 and/or deletion of exon 4. In each of these FLSs, sequence analysis revealed that these aberrant insertional sequences were flanked by consensus splice donor and acceptor sequences without nucleotide substitution, suggesting alternative splicing as the likely mutational mechanism. These variants elicited a codon frame shift by creating a premature translational stop codon, and eventually, disruption of the OTU domain (which is functionally important as an inhibitor of NF-κB activation) of A20. The expression level of aberrant A20 transcript was correlated well with persisitently enhanced status of NF-κB signalling, as evident by the phosphorylation of inhibitor of NF-κB (IκB)-α and transcription of NF-κB target genes. CONCLUSION: The results suggest that A20 inactivation by the novel aberrant splicing may contribute to RA progression by inducing persistent NF-κB activation.
23148991 Association analysis of single nucleotide polymorphisms of proinflammatory cytokine and th 2013 Jan OBJECTIVE: To analyze the relationship of genetic polymorphisms in IL1β, IL6, TNF-α genes and their receptors genes with rheumatoid arthritis (RA) for northwest Han Chinese. This study also explores whether there are gene-gene interactions among these genetic polymorphisms. METHODS: A total of 452 patients with RA and 373 matched healthy controls were enrolled to carry out a case-control study for 16 SNPs of IL1B-511 C>T, IL1B-31 T>C, IL1B+3954 C>T, IL1RN T>C, IL6-597 G>A, IL6-572 G>C, IL6-174 G>C, IL6R-183 G>A, IL6R exon2 T>A, IL6R exon1 A>C, TNFA-863 C>A, TNFA-857 C>T, TNFA-308 G>A, TNFA-238 G>A, TNFR1-383 A>C and TNFR2 T676G T>G from seven genes. Genotyping for the SNPs was conducted on the RotorGene 6000 PCR platform using in-house high resolution melting (HRM) approaches. Detection correctness was validated through direct sequencing. Generalized multifactor dimensionality reduction (GMDR) analysis was applied to discover likely gene-gene interaction model among the SNPs. RESULTS: The results showed that the genotype distributions of TNFA-308, TNFA-857 and TNFA-863 are significantly different between case and control groups (P=0.016, P=0.048 and P=0.016, respectively). Carriers of TNFA-857 mutant allele conferred risk to RA (OR=1.525, 95% CI=1.157-2.009) while those of TNFA-308 and TNFA-863 mutant alleles conferred protection to RA (OR=0.459, 95% CI=0.286-0.739; OR=0.490, 95% CI=0.329-0.732). GMDR analysis for the SNPs indicated that gene-gene interaction existed among IL1B-31, IL1RN, IL6-572, IL6R-183, IL6R-exon1 and TNFA-857. Thirteen of all genotypes of the six SNPs combination were discovered to have significant distribution difference between RA group and the control. CONCLUSIONS: This study demonstrated that PCR-HRM assay is a highly efficient SNP genotyping method especially for the detection of large-scale samples. The SNPs of TNFA-308 and TNFA-863 are closely associated with RA susceptibility and that gene-gene interactions may occur among the six SNPs of IL1B-31, IL1RN, IL6-572, IL6R-183, IL6R-exon1 and TNFA-857 in RA patients from northwest Chinese Han population, especially these SNPs' combination genotypes CT/TT/CC/GG/AC/CC, CT/TT/GC/AA/AC/CT and CT/CT/CC/GA/AC/CC to show high risk of RA susceptibility in our study.