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ID PMID Title PublicationDate abstract
16328196 [The prevalence of osteoporosis and associated health care use in women 45 years and older 2005 Dec The prevalence of osteoporosis and associated factors were assessed among women 45 years and older as part of the first nationwide German Telephone Health Survey (GSTel03). A total of 14.2% of women reported that a doctor had ever diagnosed them with osteoporosis. Among these about, 15% also reported a physician-diagnosed fragility fracture, the fracture question was restricted to the subgroup of women with osteoporosis. Point estimates of overall osteoporosis prevalence increased significantly across 10-year age bands from 4% in the lowest to 30% in the highest age group. There was no significant association of osteoporosis with socioeconomic status or residence in former East vs West Germany; however, osteoporosis was significantly overrepresented among women with a migration background in comparison to women born in Germany (age-adjusted odds ratio: 1.68; 95% CI: 1.07-2.63). In age-adjusted logistic regression models, osteoporosis was significantly related to physician-diagnosed arthritis or rheumatoid arthritis, significant stature loss (>5 cm) compared to height at age 25 years, postmenopausal hormone therapy, lower ratings of subjective health as well as increased utilization of health care services. No significant association was observed with body mass index computed from self-reported height and weight. In conclusion, despite methodological limitations, these population-based, representative data support the observation that osteoporosis is a prevalent and serious health problem among older women and reflect the considerable variability with regard to diagnosis and management of this condition. Studies evaluating quality of care as well as monitoring of disease endpoints and risk factors based on representative samples of the population are needed.
15899055 The active metabolite of leflunomide, A77 1726, interferes with dendritic cell function. 2005 Leflunomide, a potent disease-modifying antirheumatic drug used in the treatment of rheumatoid arthritis (RA), exhibits anti-inflammatory, antiproliferative and immunosuppressive effects. Although most of the beneficial effects of leflunomide have been attributed to its antimetabolite activity, mainly in T cells, other targets accounting for its potency might still exist. Because of mounting evidence for a prominent role of dendritic cells (DCs) in the initiation and maintenance of the immune response in RA, we analyzed the effect of the active metabolite of leflunomide (A77 1726; LEF-M) on phenotype and function of human myleloid DCs at several stages in their life cycle. Importantly, DCs differentiated in the presence of LEF-M exhibited an altered phenotype, with largely reduced surface expression of the critical co-stimulatory molecules CD40 and CD80. Furthermore, treatment of DCs during the differentiation or maturation phase with LEF-M aborted successful DC maturation. Exogenous addition of uridine revealed that DC modulation by LEF-M was independent of its proposed ability as an antimetabolite. In addition, the ability of DCs to initiate T-cell proliferation and to produce the proinflammatory cytokines IL-12 and tumour necrosis factor-alpha was markedly impaired by LEF-M treatment. As a molecular mechanism, transactivation of nuclear factor-kappaB, an transcription factor essential for proper DC function, was completely suppressed in DCs treated with LEF-M. These data indicate that interference with several aspects of DC function could significantly contribute to the beneficial effects of leflunomide in inflammatory diseases, including RA.
15827069 Etoricoxib: a highly selective COX-2 inhibitor. 2005 May OBJECTIVE: To review the available literature evaluating the pharmacology, pharmacokinetics, clinical efficacy, and adverse effects of etoricoxib, a highly selective cyclooxygenase-2 (COX-2) inhibitor that is not currently approved for use in the US. DATA SOURCES: Literature retrieval was accessed through MEDLINE (1966-December 2004), Current Contents (1998-December 2004), and Cochrane Library (4th quarter 2004). References from retrieved articles, information from the manufacturer, and abstracts from the American College of Rheumatology and Annual European Congress of Rheumatology meetings were searched. STUDY SELECTION AND DATA EXTRACTION: All clinical trials published in English evaluating etoricoxib were included in this review. An abstract was excluded if it presented preliminary data from trials that are now published, analyzed data previously reported in a published clinical trial, or compared etoricoxib with placebo for an indication with published active-comparator controlled trials. DATA SYNTHESIS: Twelve clinical trials evaluating efficacy were reviewed. Efficacy for acute pain has been evaluated in acute gout, primary dysmenorrhea, and dental surgery and for chronic pain in rheumatoid arthritis, osteoarthritis, and chronic lower back pain. For safety, 3 clinical trials and 6 retrospective analyses of gastrointestinal, renovascular, or cardiovascular adverse effects were reviewed. CONCLUSIONS: Available studies demonstrate the efficacy of etoricoxib compared with nonsteroidal antiinflammatory drugs, but no published studies to date have compared etoricoxib with other selective COX-2 inhibitors. While these agents have demonstrated a significant reduction in gastrointestinal adverse effects, the cardiovascular adverse effects of selective COX-2 inhibition are not well defined. Further study is necessary to delineate the benefits and risks of etoricoxib compared with alternative treatment regimens.
15801031 Employment across chronic inflammatory rheumatic diseases and comparison with the general 2005 Apr OBJECTIVE: To compare labor force participation across chronic inflammatory rheumatic diseases in order to assess the influence of the disease, disease duration, sex, education, and labor market conditions on employment. METHODS: Data from the German rheumatological database on outpatients of working age (20-59 yrs) between 1993 and 2001 were analyzed. The patients had rheumatoid arthritis (RA; n = 26,071), ankylosing spondylitis (AS; n = 5564), psoriatic arthritis (PsA; n = 6041), systemic lupus erythematosus (SLE; n = 4603), systemic sclerosis (SSc; n = 802), or Wegener's granulomatosis (WG; n = 385). Using population data, standardized employment ratios (SER) and part-time employment ratios of observed versus expected cases with 95% CI were calculated by means of indirect standardization for age and year of documentation. RESULTS: Across all diseases the overall employment rates were significantly lower than in the general population. Significant differences in SER were found between the diseases. The lowest SER of 0.76 to 0.81 (1.0 = population) were found in patients with RA, SLE, SSc, and WG. Higher SER were seen in AS (0.94) and PsA (0.92). In patients with a disease duration > 10 years the relative risk of being employed compared to RA, was 1.42 for AS, 1.26 for PsA, and 1.15, 1.03, 0.62 for PsA, SLE, SSc and WG, respectively. Comparing areas with low and high unemployment rates, a highly significant influence of labor market conditions on the SER was observed. The SER were significantly lower in patients with < 10 years of school education. CONCLUSION: Differences between employment rates in the population and the rates for the diseases under study are smaller than assumed by most clinical studies, especially in AS and PsA. However, these differences increase with longer disease duration. Specific measures to prevent patients from losing their job are needed, especially in areas with overall high unemployment.
16884970 Tumor necrosis factor antagonists: different kinetics and/or mechanisms of action may expl 2006 Dec OBJECTIVE: Tumor necrosis factor (TNF) antagonists fall into 2 classes:etanercept (ETA) is a soluble TNF receptor, while infliximab (INF) and adalimumab (ADA) are monoclonal antibodies against TNF. All 3 drugs are effective in treating rheumatoid arthritis. However, these agents have been associated with an increased risk of granulomatous infections, such as tuberculosis and histoplasmosis. Several reports indicate that the incidence of granulomatous infections may potentially be higher in individuals treated with INF than ETA. METHODS: We conducted a comprehensive literature search (1966 to 2004) to review the role of TNF in normal and disease states, and the mechanisms of action of the TNF inhibitors. Specifically, we searched for possible mechanisms for the apparent increase in granulomatous infections associated with TNF inhibitors and for reasons that there may be differences between them. RESULTS: Infection may result from a number of differences between ETA and INF or ADA. First, binding avidities are different, with ETA binding in a 1:1 ratio and INF/ADA binding in 2 to 3:1 ratios. Second, the clearances of ADA, ETA, and INF are different, being about 13 times higher for ETA than INF or ADA, thus resulting in higher steady-state drug levels for ADA and INF. Also, the methods of administration are different, intravenously (for INF) versus subcutaneously (for ETA and ADA), which results in lower peak concentrations for ETA and ADA, potentially explaining some of the differences in effects on granuloma formation. Third, INF and ADA have somewhat different mechanisms of action from ETA: INF and ADA are associated with antibody-mediated cell lysis, while ETA is not; INF may induce apoptosis in some tissues (eg, gastrointestinal [GI] mucosa) while ETA does not--although this is controversial and may not be true at steady state in synovium, where both drugs seem to cause apoptosis; ETA binds lymphotoxin-alpha while INF does not (ETA may thus be more efficient at preventing granuloma formation by this mechanism than INF); finally, ADA and INF seem to inhibit IFN-gamma expression (probably indirectly), while ETA does not. CONCLUSIONS: There are significant differences between the 2 classes of TNF antagonists in terms of both their kinetics and mechanisms of action. These differences may help explain the apparent differences in the incidence of granuloma-dependent infections among them.
16841861 n-3 polyunsaturated fatty acids, inflammation, and inflammatory diseases. 2006 Jun Inflammation is part of the normal host response to infection and injury. However, excessive or inappropriate inflammation contributes to a range of acute and chronic human diseases and is characterized by the production of inflammatory cytokines, arachidonic acid-derived eicosanoids (prostaglandins, thromboxanes, leukotrienes, and other oxidized derivatives), other inflammatory agents (e.g., reactive oxygen species), and adhesion molecules. At sufficiently high intakes, long-chain n-3 polyunsaturated fatty acids (PUFAs), as found in oily fish and fish oils, decrease the production of inflammatory eicosanoids, cytokines, and reactive oxygen species and the expression of adhesion molecules. Long-chain n-3 PUFAs act both directly (e.g., by replacing arachidonic acid as an eicosanoid substrate and inhibiting arachidonic acid metabolism) and indirectly (e.g., by altering the expression of inflammatory genes through effects on transcription factor activation). Long-chain n-3 PUFAs also give rise to a family of antiinflammatory mediators termed resolvins. Thus, n-3 PUFAs are potentially potent antiinflammatory agents. As such, they may be of therapeutic use in a variety of acute and chronic inflammatory settings. Evidence of their clinical efficacy is reasonably strong in some settings (e.g., in rheumatoid arthritis) but is weak in others (e.g., in inflammatory bowel diseases and asthma). More, better designed, and larger trials are required to assess the therapeutic potential of long-chain n-3 PUFAs in inflammatory diseases. The precursor n-3 PUFA alpha-linolenic acid does not appear to exert antiinflammatory effects at achievable intakes.
16818966 Revision total knee arthroplasty: 1990 through 2002. A review of the Finnish arthroplasty 2006 Jul BACKGROUND: National and regional arthroplasty registries have been used to study the results of primary total knee arthroplasties. The purpose of this paper was to present the results of revision total knee replacements and describe predictors of survival of those replacements, with repeat revision as the end point. METHODS: The nationwide Finnish Arthroplasty Registry included 2637 revision total knee arthroplasties from 1990 through 2002. Survivorship of the revision total knee arthroplasties was analyzed, with repeat revision as the end point. The survivorship analyses comprised evaluations of the proportional hazards assumption followed by calculations of univariate and multivariate statistics and model diagnostics as appropriate. RESULTS: The survival rate following the revision total knee arthroplasties was 95% (95% confidence interval, 94% to 96%) at two years (1874 knees), 89% (95% confidence interval, 88% to 90%) at five years (944 knees), and 79% (95% confidence interval, 78% to 81%) at ten years (141 knees). Multivariate regression analysis showed the most significant predictors of prosthetic survival to be the age of the patient and the life in service of the primary total knee replacement (that is, the time between the primary total knee replacement and the revision). Survivorship was also significantly predicted by the year of the first revision total knee arthroplasty and the reason for the revision. CONCLUSIONS: An age greater than seventy years, revision five years or more after the primary arthroplasty, and absence of patellar subluxation are positive indicators of survival of a revision total knee replacement. We believe that normal aging as well as the deconditioning effect of disease (osteoarthritis and rheumatoid arthritis) and its treatment (primary total knee replacement) may lead to a reduced activity level, which, together with a presumed reluctance to operate on elderly patients, protects against repeat revisions. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions to Authors for a complete description of levels of evidence.
16622903 Quality of life and functional status in systemic sclerosis compared to other rheumatic di 2006 Jun OBJECTIVE: To assess clinical factors associated with disability and physical health in patients with systemic sclerosis (SSc) compared to psoriatic arthritis (PsA), systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA) and healthy controls. METHODS: Eighty-two patients with SSc, 82 with PsA, 74 with SLE, 42 with RA, and 60 controls were recruited from various rheumatology clinics and underwent physical examination, tender point count, Health Assessment Questionnaire Disability Index (HAQ-DI) and Short Form-36 Health Survey (SF-36) assessments. RESULTS: SSc patients were younger and had shorter disease duration than the comparator groups. SSc patients with joint involvement had significantly poorer HAQ-DI scores than patients with PsA (1.43 vs 0.84; p < 0.05), and had higher visual analog scale pain scores than RA patients (1.37 vs 1.01; p < 0.05). The SF-36 Physical Component Summary and HAQ-DI score in SSc patients were adversely affected by joint involvement (p < 0.01, p < 0.001, respectively), >or= 11 tender points (p < 0.01, p < 0.001), gastrointestinal (GI) involvement (p < 0.01, p < 0.01), and high skin score (p = 0.02, p < 0.001). CONCLUSION: Physical health relating to quality of life is adversely affected in patients with SSc. Disability is associated with the presence of >or= 11 tender points, a high skin score, and joint and GI involvement. Joint involvement in SSc is more disabling than joint involvement in PsA; and patients with SSc experience more severe pain than patients with RA.
16452262 Inflammation-susceptible Lewis rats show less sensitivity than resistant Fischer rats in t 2006 May Comparisons between Lewis and Fischer inbred strains of rats are used frequently to study the effect of inherent differences in function of the hypothalamic-pituitary-adrenal axis on pain-relevant traits, including differential susceptibility to chronic inflammatory disease and differential responsiveness to analgesic drugs. Increasing use of genetic models including transgenic knockout mice and inbred strains of rodents has raised our awareness of, and the importance of, thorough characterization (or phenotyping) of the strains of rodents being compared. Furthermore, genetic variability in analgesic sensitivity is correlated with, and may be caused by, genetically determined baseline sensitivity. Thus in this study, baseline inflammatory and thermal nociceptive sensitivities were measured in awake male and female Lewis and Fischer rats to examine whether the results could explain relevant strain differences reported in the literature. The effect of maternal separation was also examined and no effect was found on nociceptive sensitivity, corticosterone responses, or the development of adjuvant-induced arthritis, a model of rheumatoid arthritis. Lewis rats and female rats were more sensitive to thermal nociception in the tail withdrawal test (mean of 3 trials) than Fischer rats and male rats, respectively. Unexpectedly, the more inflammation-susceptible Lewis rats were less sensitive in the formalin inflammatory nociception test, and showed a significant decrease in sensitivity with repeated thermal nociceptive testing, whereas Fischer rats did not. These results affect the interpretation of previously observed results. Further study of the underlying mechanisms and the relevance to differential susceptibility to chronic inflammation is warranted.
16356770 RANKL-RANK signaling in osteoclastogenesis and bone disease. 2006 Jan Hundreds of millions of people worldwide are affected by bone-related diseases, such as osteoporosis and rheumatoid arthritis. Understanding the molecular mechanisms of bone metabolism is crucial for developing novel drugs for treating such diseases. In particular, genetic experiments showing that the receptor activator of NF-kappaB (RANK), its ligand RANKL, and the decoy receptor OPG are essential, central regulators of osteoclast development and osteoclast function were significant turning points in our understanding of bone diseases. RANKL-RANK signaling activates a variety of downstream signaling pathways required for osteoclast development. Moreover, molecular cross-talk between RANKL-RANK and other ligand-receptor systems fine-tunes bone homeostasis in normal physiology and disease. Designing novel drugs that target RANKL-RANK and their signaling pathways in osteoclasts could potentially revolutionize the treatment of many diseases associated with bone loss such as arthritis, tooth loss, cancer metastases or osteoporosis.
16320352 The PTPN22 620W allele is a risk factor for Wegener's granulomatosis. 2005 Dec OBJECTIVE: Analyses of families with multiple autoimmune disorders have revealed a functional polymorphism, 620W, in the intracellular tyrosine phosphatase gene PTPN22 as a predisposing factor for type 1 diabetes, seropositive rheumatoid arthritis, systemic lupus erythematosus, and Hashimoto thyroiditis, and the presence of the PTPN22 protein appears to herald the development of autoantibodies in these disorders. This study therefore examined whether the functionally relevant PTPN22 polymorphism is associated with Wegener's granulomatosis (WG). METHODS: A population-based study was performed for the PTPN22 polymorphism in 199 patients with WG and in 399 healthy individuals. The R620W variation was investigated by simple restriction fragment-length polymorphism analysis. RESULTS: The PTPN22 620W allele frequency was significantly increased in antineutrophil cytoplasmic antibody (ANCA)-positive WG patients compared with healthy controls (P < 0.001). The association was particularly striking in patients with kidney, lung, eye, and peripheral nervous system involvement (i.e., those with generalized WG). CONCLUSION: The PTPN22 620W allele appears to be involved in the pathogenesis of WG, and ANCA positivity seems to be the hallmark.
16178791 Therapeutic potential of glycolipid ligands for natural killer (NK) T cells in the suppres 2005 Sep NKT cells emerge as important regulatory cells in autoimmune responses. Abnormalities in the numbers and functions of natural killer T (NKT) cells have been observed in patients with autoimmune diseases as well as in a variety of mouse strains that are genetically predisposed for development of autoimmune diseases. Unlike conventional T cells that recognize peptides in association with major histocompatibility complex (MHC), NKT cells recognize glycolipid antigens presented by the non-polymorphic MHC class I-like protein, CD1d. Recently, we and other groups have demonstrated that administration of glycolipid ligands such as alpha-galactosylceramide (alpha-GC ) or its sphingosine truncated derivative, OCH suppressed autoimmune diseases such as experimental autoimmune encephalomyelitis (EAE), diabetes in NOD mice and collagen-induced arthritis (CIA) by inducing T helper (Th) 2 bias of autoimmune T cells. OCH is a unique ligand to stimulate NKT cells to selectively produce Th2 cytokines whereas alpha-GC induces both interleukin (IL)-4 and interferon (IFN)-gamma, and is more beneficial for treatment of a wide variety of Th1-mediated autoimmune diseases. The lack of polymorphism of CD1d and cross-reactive responses of mouse and human NKT cells to the same ligand indicates that targeting NKT cells with this ligand may be an attractive means for intervening in human autoimmune diseases such as type I diabetes (T1D), multiple sclerosis (MS) and rheumatoid arthritis (RA). The present review will focus on the potential roles of NKT cells in the pathogenesis of autoimmune diseases and the recent advances in glycolipid therapy for autoimmune disease models. The molecular mechanism of OCH-induced Th2-selective cytokine secretion will also be discussed.
15821811 Diagnosis of malignancies in children with musculoskeletal complaints. 2005 Jan 2 CONTEXT: Musculoskeletal complaints may be associated with neoplasias as an initial manifestation of the disease. When these symptoms predominate at the onset of the disease, the differential diagnosis includes several rheumatic diseases. OBJECTIVE: To assess the frequency, clinical features and types of cancer manifested in children presenting with musculoskeletal complaints over a seven-year period. TYPE OF STUDY: Retrospective. SETTING: Discipline of Allergy, Clinical Immunology and Rheumatology, Universidade Federal de São Paulo-Escola Paulista de Medicina. METHODS: The medical records of patients with musculoskeletal complaints and final diagnosis of malignant disease were reviewed. The data collected were: age when symptoms initially presented, age at diagnosis, clinical features presented, laboratory findings, and the initial and final diagnoses. RESULTS: A final diagnosis of cancer was found in nine out of 3,528 patients (0.25%) whose initial symptom was musculoskeletal pain. The mean time between disease onset and final diagnosis was five months. The most common features presented were pauciarticular arthritis or arthralgia involving the large joints. Juvenile rheumatoid arthritis was the most frequent initial diagnosis, in four out of nine patients. Anemia was the most frequent initial hematological change. Six out of eight patients had an increased erythrocyte sedimentation rate. The lactate dehydrogenase level was raised in five out of eight patients. The malignancies found included acute lymphocytic leukemia, acute myeloid leukemia, lymphoma, neuroblastoma and Ewing's sarcoma. DISCUSSION: The frequency of neoplasia in patients with musculoskeletal pain resembled reports in the literature. Consumptive symptoms were not the warning signal in most of our patients. In subsidiary tests, progressive anemia was the most common finding, although the peripheral blood cell count may continue to be normal for weeks or months after symptom onset. CONCLUSION: Malignancy always needs to be ruled out in cases of children with musculoskeletal complaints. Uncharacteristic clinical manifestations and nonspecific laboratory tests may cause difficulty in the final diagnosis, and rigorous investigation should be performed.
16802370 Impaired salivary gland function in NOD mice: association with changes in cytokine profile 2006 Jul OBJECTIVE: To characterize the chronologic disease course and possible interrelationships between salivary gland inflammation, hyposalivation, and cytokine levels in NOD mice, a model for Sjögren's syndrome (SS). METHODS: NOD mice of different ages were used to mimic different disease stages of SS. Histopathologic findings and rates of salivary secretion were compared between 8-week-old, 17-week-old, and 24-week-old female mice. In addition, 10 cytokines were analyzed in serum and saliva obtained from NOD and BALB/c mice. RESULTS: In NOD mice, the salivary flow rate did not change between 8 weeks and 17 weeks of age, while a significant decrease in the salivary flow rate occurred between 17 weeks and 24 weeks of age (P < 0.001). In contrast, significant histopathologic changes in the salivary glands occurred before 17 weeks of age. Chronic inflammatory cell infiltrates were characterized by T and B cell infiltration. Interestingly, in one-third of the mice, proliferating cells were observed in the focal infiltrates. Significant changes in the levels of interleukin-2 (IL-2), IL-5, and granulocyte-macrophage colony-stimulating factor in serum, and in the levels of IL-4 and tumor necrosis factor alpha (TNFalpha) in saliva occurred contemporarily with the decrease in salivary flow. Correlation analyses revealed a negative association between salivary secretion and the levels of IL-4, interferon-gamma, and TNFalpha in saliva obtained from NOD mice, while the correlation with inflammatory changes in the glands was consistently weak. CONCLUSION: Consistent with previous findings, our results indicate at least 2 phases of SS-like disease in NOD mice. Hyposalivation was preceded by inflammatory changes in the salivary glands, whereas abrupt changes in secretion occurred without significant progression of inflammation. Changes in cytokine levels are an indication of the mechanisms involved in the adaptive immune response in the transition from early to overt disease.
16465661 Muscarinic acetylcholine type-3 receptor desensitization due to chronic exposure to Sjögr 2006 Feb OBJECTIVE: Anti-muscarinic acetylcholine type-3 receptor (anti-M3R) autoantibodies have been shown to inhibit M3R-mediated responses by both in vitro contractility and fura-2 microfluorimetry analyses of intracellular calcium mobilization, suggesting an important role for anti-M3R autoantibody in secretory dysfunction. We investigated whether chronic stimulation of M3R by anti-M3R autoantibodies and/or the agonist pilocarpine results in a general M3R desensitization. METHODS: Carbachol-evoked responses of mouse-bladder smooth muscle strips were measured following exposure to anti-M3R-positive and/or anti-M3R-negative sera from either NOD/Lt mice, a model of SS-like disease, or human patients with primary SS. RESULTS: Bladder smooth muscle strips isolated from NOD/Lt mice with circulating anti-M3R autoantibodies exhibited lower carbachol-evoked responses than smooth muscle strips from anti-M3R autoantibody-negative NOD/Lt mice and control C57BL/6 mice. Repeated pilocarpine injections of NOD mice for 6 days also revealed M3R desensitization in the agonist-evoked contractile assay, whereas age and sex matched C57BL/6 mice injected with pilocarpine for the same period showed a 2-fold higher response. Incubation of smooth muscle strips with sera obtained from patients with primary SS resulted in both stimulated and inhibited responses. CONCLUSION: These results support the hypothesis that chronic stimulation of membrane-bound M3R can result in receptor desensitization, and raise questions about repeated use of pilocarpine by patients positive for anti-M3R autoantibodies.
16095123 A novel polymorphism of the SSA1 gene is associated with anti-SS-A/Ro52 autoantibody in Ja 2005 Jul OBJECTIVE: To investigate the association of polymorphisms of the SSA1 gene (OMIM 109092) with primary Sjögren's syndrome (SS) and anti-SS-A/Ro52 antibody production. METHODS: Polymorphisms of SSA1 gene in 111 Japanese SS patients and in 97 healthy controls were analyzed with polymerase chain reaction and automated DNA sequencing. RESULTS: A new single-nucleotide polymorphism (SNP) was identified in intron 1 at position 7216. The allele frequency and genotype of 7216A/G were not significantly different between SS patients and control subjects. However, the allele frequency and genotype of 7216A/G were associated with the presence of anti-SS-A/Ro52 antibody among primary SS patients. The association was not found in patients with SLE, suggesting the limited role for the SNP in anti-SS-A/Ro52 antibody production. The 9571C/T polymorphism, which has been shown to associate with anti-SS-A/Ro52 antibody in Caucasian patients, was not associated with the presence of anti-SS-A/Ro52 antibody in Japanese patients. CONCLUSIONS: 7216A/G polymorphism of SSA1 gene may be one of the genetic factors that determine the presence of anti-SS-A/Ro52 antibody in patients with primary SS.
15817659 Salivary gland and peripheral blood T helper 1 and 2 cell activity in Sjögren's syndrome 2005 Oct OBJECTIVES: To investigate whether differences in T helper (Th) 1 and Th2 cell activity in salivary glands ("local") or ("peripheral") blood can discriminate between Sjögren's syndrome (SS) and non-Sjögren's sicca syndrome (nSS-sicca). Additionally, to study relationships of local and peripheral Th cell activities with each other and with disease activity measures. METHODS: 62 sicca patients (32 with SS, 30 with nSS-sicca) were studied. Local Th1 (interferon gamma (IFNgamma)) and Th2 (interleukin (IL) 4) activity were determined using immunohistochemistry. T cell production of IFNgamma and IL4 in peripheral blood (PB) was determined by ELISA. Erythrocyte sedimentation rate (ESR) and serum IgG were considered disease activity measures. RESULTS: ESR and serum IgG were higher in patients with SS than in patients with nSS-sicca. Local Th1 cell activity was higher and PB Th1 activity lower in patients with SS than in those with nSS-sicca. Th2 cell activity did not differ significantly between the patient groups. The ratio IFNgamma/IL4 was higher in salivary glands and lower in PB in patients with SS than in patients with nSS-sicca. Local and peripheral Th1 and Th2 cell activities correlated with ESR and serum IgG levels. ESR, serum IgG, and local or peripheral Th1 or Th2 cell activity did not discriminate between patients with SS and nSS-sicca. CONCLUSIONS: An imbalance between Th1 and Th2 activity in sicca patients is clearly related to the severity of disease, but cannot be used to distinguish between patients with SS and those with nSS-sicca.
16186536 Painful small-fiber neuropathy in Sjogren syndrome. 2005 Sep 27 Of 20 consecutive patients with Sjögren neuropathy, 16 (80%) presented with burning feet and 12 (60%) with non-length-dependent sensory symptoms. Leg and thigh skin biopsies, performed in 13 patients, including 7 with normal electrophysiology, showed either reduced epidermal nerve fiber (ENF) density or abnormal morphology. ENF loss was frequently non length dependent, suggesting that patients with this disorder commonly have a small-fiber sensory neuronopathy rather than a "dying-back" axonopathy.
16815863 Anti-proteasome autoantibodies contribute to anti-nuclear antibody patterns on human laryn 2007 Jan BACKGROUND: Autoantibodies to the 20S proteasome represent an unspecific but common serological phenomenon in patients with systemic autoimmune diseases. Interestingly, a high prevalence of these antibodies have been observed in patients with connective tissue diseases, where anti-nuclear antibodies (ANAs) serve as an important diagnostic screening test. OBJECTIVE: To disclose interference of anti-proteasome antibodies with known ANA patterns. METHODS: Anti-proteasome antibodies were isolated for comprehensive immunofluorescence analyses. The immunofluorescence pattern of human anti-proteasome antibodies was compared with a panel of monoclonal and polyclonal reference antibodies, and colocalisation was analysed using confocal microscopy. RESULTS: Anti-proteasome antibodies clearly contributed to the ANA patterns of their respective serum samples from patients with different rheumatic disorders. In addition to the nuclear pattern, proteasomal staining was also detectable in the cytoplasm, at the endoplasmic reticulum and perinuclear regions showing features overlapping with other known autoantibodies such as those to mitochondria. The specificity of anti-proteasome antibodies was proved by competition experiments and by colocalisation with monoclonal reference antibodies in confocal microscopy. CONCLUSION: In ANA diagnostics, interference of anti-proteasome antibodies will have to be taken into account, especially in the differentiation of anti-cytoplasmatic autoantibodies.
16802355 Anti-20S proteasome autoantibodies inhibit proteasome stimulation by proteasome activator 2006 Jul OBJECTIVE: The ubiquitin-proteasome system plays a central role in cellular homeostasis as well as in regulation of the inflammatory and stress responses. However, the occurrence of autoantibodies against 20S proteasome has, to date, been considered to be a non-specific epiphenomenon in patients with autoimmune disorders. This study was undertaken to analyze the properties of antiproteasome antibodies by investigating their influence on the proteolytic activity of the proteasome complex. METHODS: The 20S proteasome, with or without addition of the proteasome activator (PA28), was preincubated with affinity-purified human antiproteasome antibodies. Proteolytic activity was estimated using fluorogenic peptides as substrate. RESULTS: The baseline proteolytic properties of the 20S proteasome core complex were not influenced by the autoantibodies in vitro. In contrast, all human antiproteasome antibodies analyzed efficiently blocked the enhanced proteasomal substrate cleavage provided by PA28. A similar influence of proteasome activation was observed upon preincubation with affinity-purified sheep polyclonal or mouse monoclonal antiproteasome antibody, whereas human immunoglobulin controls exhibited no effect. CONCLUSION: Autoantibodies against 20S proteasomes are able to block proteasome activation by PA28, binding to their native antigen in vitro. Antibody targeting of the interaction between 20S proteasome and PA28 represents a novel mechanism of proteasome inhibition.