Search for: rheumatoid arthritis methotrexate autoimmune disease biomarker gene expression GWAS HLA genes non-HLA genes
| ID | PMID | Title | PublicationDate | abstract |
|---|---|---|---|---|
| 9106074 | The role of nitric oxide in multiple sclerosis. | 1997 Mar | During the past decade nitric oxide has emerged as an important mediator of physiological and pathophysiological processes. Elevated nitric oxide bio-synthesis has been associated with nonspecific immune-mediated cellular cytotoxicity and the pathogenesis of chronic, inflammatory autoimmune diseases including rheumatoid arthritis, insulin-dependent diabetes, inflammatory bowel disease, and multiple sclerosis. Recent evidence suggests, however, that nitric oxide is also immunoregulatory and suppresses the function of activated proinflammatory macrophages and T lymphocytes involved in these diseases. This article reviews the role of nitric oxide in the biology of central nervous system glial cells (astrocytes and microglia) as it pertains to the pathogenesis of multiple sclerosis in humans and experimental allergic encephalitis, the animal model of this disease. Although nitric oxide has been clearly implicated as a potential mediator of microglia-dependent primary demyelination, a hallmark of multiple sclerosis, studies with nitric oxide synthase inhibitors in the encephalitis model have been equivocal. These data are critically reviewed in the context of what is know from clinical research on the nitric oxide pathway in multiple sclerosis. Specific recommendations for future preclinical animal model research and clinical research on the nitric oxide pathway in patients are suggested. These studies are necessary to further define the role of nitric oxide in the pathology of multiple sclerosis and to fully explore the potential for nitric oxide synthase inhibitors as novel therapeutics for this disease. | |
| 9029128 | Mechanisms of action of antimalarials in inflammation: induction of apoptosis in human end | 1997 Feb 15 | Antimalarials are beneficial therapeutic agents in systemic lupus and rheumatoid arthritis. These autoimmune diseases have abnormally low apoptosis of inflammatory cells. Both disorders have an abnormal angiogenesis. In the present report, antimalarials were demonstrated to selectively increase apoptosis of HUVECs in vitro. A 24-h exposure to 50 or 150 microM of the drugs was associated with a significant loss of substrate-adherent cells. Chloroquine exhibited an inhibitory effect on HUVEC proliferation over 7 days. Programmed cell death in HUVECs rendered nonadherent by chloroquine was confirmed by the induction of DNA fragmentation in floating cells. Northern blot analysis revealed a rapidly increased expression of the bcl-x(s) gene without any change in the expression of the bcl-2 gene, indicating that HUVECs under chloroquine were undergoing apoptosis. The onset of the apoptotic cascade in HUVECs appeared shortly after the addition of chloroquine. The effect of chloroquine on apoptosis was distinct from acute cell lysis and was restricted to HUVECs. Antimalarials also induced IL-1alpha production. In parallel, chloroquine alone did not increase the expression of IL-6. Anti-IL-1alpha Ab or IL-1Ra only marginally reversed chloroquine-induced depression of proliferation for the low drug concentration, but not the massive cell death effect at and above 50 microM. Taken together, these data may indicate that antimalarials repress angiogenesis. The autocrine mechanism involving IL-1alpha accounts only for a minor fraction of the full antiendothelial effect of chloroquine, which is mainly dependent on apoptosis. | |
| 11699390 | Triptolide, a novel immunosuppressive and anti-inflammatory agent purified from a Chinese | 2001 Jul | Triptolide is a diterpenoid triepoxide purified from a Chinese herb Tripterygium Wilfordii Hook F (TWHF). TWHF has been used in traditional Chinese medicine for more than two thousand years. However, its potential value was recognized by the western medicine only after investigators observed the effectiveness of TWHF in the treatment of leprosy and rheumatoid arthritis. Triptolide has been identified as the major component responsible for the immunosuppressive and anti-inflammatory effects of TWHF. Triptolide inhibits both Ca(2+)-dependent and Ca(2+)-independent pathways and affects T cell activation through inhibition of interleukin-2 transcription at a site different from the target of cyclosporin A. Triptolide also has inhibitory effects on a variety of proinflammatory cytokines and mediators and on the expression of adhesion molecules by endothelial cells. Triptolide is effective for the treatment of a variety of autoimmune diseases and in prevention of allograft rejection and graft-versus-host disease in both animals and humans. Moreover, triptolide possesses antitumor and male anti-fertility effect. However, the toxicities of triptolide may be associated with renal, cardiac, hematopoietic and reproductive systems. Currently available data suggest that triptolide is a promising immunosuppressive and anti-inflammatory agent and should be explored further in autoimmune diseases and transplantation. | |
| 11686224 | Expression of group II phospholipase A2 in the liver in acute pancreatitis. | 2001 Nov | BACKGROUND: A number of distinct secretory phospholipases A2 (PLA2) have been characterized in the human. Elevated group II PLA2 serum levels are associated with inflammatory diseases such as infections, septic shock, rheumatoid arthritis, multiple organ failure and acute pancreatitis. The cellular source of circulating group II PLA2 has not been defined unequivocally. The possible role of the liver as a source of circulating group II PLA2 in acute pancreatitis was studied using liver biopsies from five patients operated on for necrotizing acute pancreatitis and from two control liver samples. METHODS: Reverse transcription polymerase chain reaction (RT PCR), northern hybridization and in situ hybridization were used to study the expression of group II PLA2. Immunohistochemistry was used to study the localization of the group II PLA2 protein in liver cells and time-resolved fluoroimmunoassay to measure the plasma group II PLA2 content. RESULTS: Expression of group II PLA2 was found in the livers of patients with acute pancreatitis by RT PCR and confirmed by northern hybridization. Group II PLA2 mRNA was localized in hepatocytes by in situ hybridization. Faint immunopositivity was found in Kupffer cells. Time-resolved fluoroimmunoassay revealed elevated concentration of group II PLA2 in plasma samples. Only low levels of expression were found in the control livers. CONCLUSIONS: Group II PLA2 is expressed in the livers of patients suffering from acute pancreatitis but not in the livers of patients without pancreatic disease. The current results support the idea that hepatocytes are an important source of circulating group II PLA2 in inflammatory diseases. | |
| 11685366 | Cyclic mechanical stretching enhances secretion of Interleukin 6 in human tendon fibroblas | 2001 Sep | Accelerated rehabilitation after tendon and ligament injuries is widely accepted to avoid adverse effects of immobilization. However, progressive rehabilitation may also lead to an excessive inflammatory soft tissue response. To investigate the amount of loading necessary to accelerate the healing process without causing damage to the healing tissue, we experimentally stretched human tendon fibroblasts of healthy tendons 15 and 60 min with 1 Hz and an elongation of 5% and measured the secretion of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta1 (TGF-beta1), platelet-derived growth factor (PDGF), and fibroblast growth factor basic (bFGF). Secretion of IL-6 was significantly induced by 15 min of cyclic biaxial mechanical stretching after 4 and 8 h observation time and by 60 min stretching and 2 h observation time. The growth factors TGF-beta1, bFGF, and PDGF were secreted by human tendon fibroblasts both in stretched cells and controls; however, no increases were related to mechanical stretching. There was no measurable secretion of TNF-alpha in human tendon fibroblasts. These findings suggest that the inflammatory reaction often seen during physiotherapy after tendon and ligament injuries is caused in part by secretion of IL-6 from the stretched human tendon fibroblasts. IL-6 may cause exaggerated proliferation of fibroblasts and synovial cells as seen in rheumatoid arthritis and arthrofibrosis. However, physiological proliferative reactions leading to repair of injured tissue are also possible. IL-6 measured in the synovial fluid may be an important predictor for monitoring and improving therapeutic strategies in terms of tendon/ligament healing. | |
| 11587095 | Drug-induced pneumonitis: the role of methotrexate. | 2001 Oct | Methotrexate (MTX) is a folate antagonist used in several chronic inflammatory and neoplastic conditions. Pulmonary toxicity occurs in 0.5% to 14% of patients receiving low-dose MTX. Manifestations of pulmonary toxicity are protean and include parenchymal inflammation, pneumonia, airway hyperreactivity, air trapping and possibly neoplasm. We performed an exhaustive review of the English literature and identified 189 cases of methotrexate-induced pneumonitis (MIP). Rheumatoid arthritis (RA) was the most frequent underlying disease. In most patients, symptoms present subacutely with progression over several weeks. Most patients present with dyspnea, dry cough, fever, and bibasilar crackles. Peripheral eosinophilia has been cited in one third of cases. The chest radiograph may be normal, but more commonly reveals bilateral interstitial or mixed, interstitial and alveolar infiltrates with a predilection for the bases. Chest computed tomography (CT) scans demonstrate ground-glass opacities, interstitial infiltrates, septal lines or widespread consolidation. Pulmonary function studies reveal a restrictive ventilatory defect and/or impaired gas exchange. Bronchoalveolar lavage (BAL) may be helpful in ruling out an infectious etiology and in supporting the diagnosis of MIP. Cellular interstitial infiltrates, granulomas, fibrosis, atypical epithelial cells, and diffuse alveolar damage (DAD) are the main histologic features. Once MIP is suspected, the MTX should be withdrawn. Corticosteroids may accelerate resolution and are recommended in severe or fulminant cases. The prognosis of MIP is usually favorable, but occasionally the outcome may be fatal. | |
| 11577996 | Establishment of a consistent L929 bioassay system for TNF-alpha quantitation to evaluate | 2001 Aug | TUMOR necrosis factor-alpha (TNF-alpha) plays an important role in the pathogenesis of rheumatoid arthritis. The present study was to evaluate the effects of lipopolysaccharide (LPS), phytomitogens and cytodifferentiation agents on cytotoxicity of TNF-alpha secreted by adherent human mononuclear cells (AMC). TNF-alpha cytotoxicity in LPS-treated, phytomitogen-treated, and cytodifferentiation agent-treated AMC supernatants were analyzed by the L929 bioassay system. Our results showed that LPS could induce homogeneous TNF-alpha production by AMC whereas, in addition to TNF-alpha, phytomitogens could also induce other TNF-like factors. Neither methotrexate, retinoic acid nor sodium butyrate can inhibit TNF-alpha cytotoxicity, while hexamethylene bisacetamide could not only inhibit TNF-alpha cytotoxicity but also TNF-alpha inducing ability of LPS to AMC. | |
| 11472248 | Mediterranean diet and health: biological importance of olive oil. | 2001 Jul | Olive oil, the main fatty component of the Mediterranean diet, is characterized by consisting of monounsaturated fatty acids as well as by its elevated content in antioxidant agents. This oil exhibits numerous biological functions which are beneficial for the state of health. A diet rich in monounsaturated fatty acids provides an adequate fluidity to the biological membranes, diminishing the hazard of lipid peroxidation which affects polyunsaturated fatty acids. Moreover, the antioxidants present in olive oil are able to scavenge free radicals and afford an adequate protection against peroxidation. Regarding the heart, olive oil decreases the plasmatic levels of LDL-cholesterol and increases those of HDL-cholesterol, hence diminishing the risk of suffering from heart complaints. In this context, it has been suggested that increased consumption of monounsaturated fatty acids in place of polyunsaturated fatty acids will render circulating lipoproteins less sensitive to peroxidation and thereby diminish the development of atherosclerosis. Olive oil has also been proven to contribute to a better control of the hypertriglyceridemia accompanying diabetes and may reduce the risk of breast cancer and colorectum. On the other hand, several investigations have suggested that olive oil can be beneficial in inflammatory and autoimmune diseases, such as rheumatoid arthritis. In this sense, some reports have indicated that olive oil modifies inflammatory cytokines production. As for the digestive system, olive oil enhances gallbladder emptying consequently reducing cholelithiasis risk, decreases the pancreatic exocrine secretion and gastric secretory function in response to food. Finally, it has been demonstrated that a diet rich in olive oil is associated with a high percentage of gastric ulcer healing and affords a higher resistance against non steroidal antiinflammatory drugs-induced gastric ulcerogenesis. | |
| 11451713 | Treatment of protein-energy malnutrition in chronic nonmalignant disorders. | 2001 Jul | Protein-energy malnutrition (PEM) is common in connection with chronic disease and is associated with increased morbidity and mortality. Because the risk of PEM is related to the degree of illness, the causal connections between malnutrition and a poorer prognosis are complex. It cannot automatically be inferred that nutritional support will improve the clinical course of patients with wasting disorders. We reviewed studies of the treatment of PEM in cases of chronic obstructive pulmonary disease, chronic heart failure, stroke, dementia, rehabilitation after hip fracture, chronic renal failure, rheumatoid arthritis, and multiple disorders in the elderly. Several methodologic problems are associated with nutrition treatment studies in chronically ill patients. These problems include no generally accepted definition of PEM, uncertain patient compliance with supplementation, and a wide range of outcome variables. Avail-able treatment studies indicate that dietary supplements, either alone or in combination with hormonal treatment, may have positive effects when given to patients with manifest PEM or to patients at risk of developing PEM. In chronic obstructive pulmonary disease, nutritional treatment may improve respiratory function. Nutritional therapy of elderly women after hip fractures may speed up the rehabilitation process. When administered to elderly patients with multiple disorders, diet therapy may improve functional capacity. The data regarding nutritional treatment of the conditions mentioned above is still inconclusive. There is still a great need for randomized controlled long-term studies of the effects of defined nutritional intervention programs in chronically ill and frail elderly with a focus on determining clinically relevant outcomes. | |
| 11334384 | Apoptosis in autoimmune diseases. | 2001 Apr | Over the past decade, our understanding of apoptosis, or programmed cell death, has increased greatly, with the identification of some of the major components of the apoptotic program and the processes regulating their activation. Although apoptosis is an intrinsic process present in all cells, it can be regulated by extrinsic factors, including growth factors, cell surface receptors, cellular stress and hormones. Apoptotis plays an important role in autoimmune diseases. Normal thyrocytes could induce apoptosis of infiltrating activated T cells and protect against attack by such cells, i.e., the normal thyroid tissues act as an immune privileged site. In Hashimoto's thyroiditis (HT), Fas-mediated apoptosis of thyrocytes in a section of tissues is due to at least two separate mechanisms, the first by infiltrating activated T cells, and the other by FasL-positive thyrocytes in a suicidal or fratricidal fashion. A common feature of autoimmune diseases such as systemic lupus erythematosus (SLE) is the breakdown of tolerance of self antigens, a consequence of which is the production of autoantibodies reactive with multiple self proteins. Evidence is accumulating that modifications of autoantigens during apoptosis lead to the development of autoantibodies by bypassing the normal mechanisms of tolerance. Tissue homeostasis is maintained through a balance between cell proliferation and apoptotic cell death. Rheumatoid arthritis (RA) is characterized by pronounced hyperplasia of the synovial tissue, cell infiltration and periarticular osteoporosis. Enhanced Bcl-2 expression and NF-kappaB nuclear translocation of synovial cells are induced by inflammatory cytokines and/or growth factors. These synovial cells become resistant toward apoptosis triggered by various stimuli. The infiltrated cells which are defect in activation-induced cell death can cause autoimmunity by allowing the survival of autoreactive T and B cells. These data suggest that apoptosis might be implicated with the pathogenesis of autoimmunity, whereas the mechanisms might be distinct in each autoimmune disease. | |
| 11320025 | Keratitis, ulceration, and perforation associated with topical nonsteroidal anti-inflammat | 2001 May | PURPOSE: To report corneal complications associated with topical nonsteroidal anti-inflammatory drugs (NSAIDs). DESIGN: Retrospective, noncomparative interventional case series. PARTICIPANTS: Eighteen eyes of 16 patients with adverse corneal events associated with NSAID use. METHODS: Evaluation of 16 patients referred for management of corneal complications during use of topical NSAIDs (ketorolac tromethamine [Acular], diclofenac sodium [Voltaren], diclofenac sodium [Falcon DSOS]). MAIN OUTCOME MEASURES: Type and severity of corneal complications. RESULTS: Of the 16 patients, two experienced severe keratopathy, three experienced ulceration, six experienced corneal or scleral melts, and five experienced perforations. Eleven patients had recent cataract surgery; nine of these were on concurrent topical steroids and antibiotics. Another patient who did not have recent surgery was using concurrent topical steroids without antibiotics for sarcoid uveitis. Systemic associations included two patients with rheumatoid arthritis, one patient with asymptomatic Sjogren's syndrome, and two with rosacea. CONCLUSIONS: Topical NSAIDs were associated with corneal complications in 18 eyes of 16 patients. Potential risk factors include conditions that predispose the patient to corneal melting, concurrent topical steroids, and epithelial keratopathy in the early postoperative period. | |
| 11311066 | Design, synthesis, and discovery of a novel CCR1 antagonist. | 2001 Apr 26 | The CC chemokines may play an important role in the pathogenesis of chronic inflammatory diseases including rheumatoid arthritis, and their effects are thought to be mediated through CCR1 receptors. Several nonpeptide CCR1 receptor antagonists that showed high affinity for human CCR1 receptors have been identified; however, their effectiveness in animal models of inflammatory diseases has been scarcely demonstrated, probably due to species selectivity of the antagonists. To elucidate the pathophysiological role of CCR1 receptors in murine models of disease, we looked for a potent antagonist for both murine and human CCR1 receptors. Screening of our chemical collection for inhibition of (125)I-MIP-1alpha binding to human CCR1 receptors transfected in CHO cells led to the identification of xanthene-9-carboxamide 1a as the lead compound. Derivatization of 1a by quaternarizing the piperidine nitrogen with various alkyl groups and by installing substituents into the xanthene moiety dramatically improved the inhibitory activity against both human and murine CCR1 receptors. As a result, 2q-1 showing IC(50) values of 0.9 and 5.8 nM for human and murine CCR1 receptors, respectively, was discovered. This compound is the first murine CCR1 receptor antagonist and may be a useful tool for clarifying the role of CCR1 receptors in murine models of disease. | |
| 11249493 | Current treatment of asthma--focus on leukotrienes. | 2000 Jul | Since their identification in 1979, the cysteinyl leukotrienes (cysLTs) have been shown to be prominent in many inflammatory conditions, including asthma, allergic rhinitis, rheumatoid arthritis, psoriasis, cystic fibrosis and inflammatory bowel disease. They are potent pro-inflammatory agents, as well as causing bronchoconstriction, and undoubtedly have a role in asthma. The cysLTs are products of arachidonic acid metabolism and have been shown to have effects via a cysteinyl leukotriene receptor (CysLTR1) on vascular permeability, mucus production, chemotaxis and bronchial smooth muscle. Their detection in certain body fluids in allergic, aspirin-sensitive and exercise-induced asthma is well documented and potential roles in pathogenesis, proposed. The development of agents affecting production or action offers an exciting new approach to the treatment of asthma. Two approaches to antileukotriene therapy have been developed: blocking their production by inhibiting the action of 5-lipoxygenase enzyme or blocking the CysLTR1. Both approaches have been tried in studies in asthma and overall the results are encouraging, with a decrease in both daytime and nocturnal symptoms, a decrease in additional beta 2 agonist usage and improvement in lung function. The changes, however, are small in some studies. This may be a reflection of disease severity in the study subjects, but of note is a heterogeneity of response to these treatments that may be genetically determined. Antileukotriene therapy has been shown to have an effect in specific types of asthma where the role of cysLTs seems well established--aspirin-sensitive/intolerant asthma and exercise-induced asthma. Longer term studies are needed in other areas such as severe asthma and chronic persistent asthma in both children and adults to provide evidence for the appropriate placement of antileukotriene treatment in current asthma guidelines, in comparison with other established treatments. | |
| 11231954 | Anti-tumor necrosis factor monoclonal antibody therapy for gastrointestinal Behçet's dise | 2001 Mar | Behçet's disease (BD) is a multisystem immune-mediated inflammatory disorder that involves the intestine in 3%-26% of cases. Corticosteroids, 5-aminosalicylic acid derivatives, immunomodulators, and more recently thalidomide and pentoxifylline have been used to treat BD with varying degrees of success. Tumor necrosis factor (TNF)-alpha is believed to play a pivotal role in this T helper cell type 1 (Th1)-mediated disease. Infliximab, a chimeric monoclonal antibody to TNF-alpha, has been demonstrated to be an effective therapy for Crohn's disease and rheumatoid arthritis, 2 other Th1-mediated disorders. We describe a patient with chronically active, steroid-dependent BD involving the gastrointestinal tract who received 4 doses of infliximab during a 6-month period. Because most of her symptoms were gastrointestinal, the Crohn's Disease Activity Index (CDAI) was used to assess response. A rapid and dramatic improvement in both gastrointestinal and extraintestinal symptoms was observed. The CDAI score decreased from 270 points (preinfusion) to 13 points by week 2, and remission was sustained despite complete withdrawal of steroids. Colonoscopy performed 10 weeks after the first infusion showed marked endoscopic and histologic improvement. This report suggests that infliximab may be an effective new therapy for gastrointestinal BD, and perhaps other manifestations of BD as well. | |
| 11207664 | CD4+ and CD8+ clonal T cell expansions indicate a role of antigens in ankylosing spondylit | 2001 Feb | Ankylosing spondylitis (AS) is a complex genetic disease in which both MHC and non-MHC genes determine disease susceptibility. To determine whether the T cell repertoires of individuals with AS show signs of increased stimulation by exogenous antigens, CD4+ and CD8+ T cell subsets of five monozygotic HLA-B27+ twins (two concordant and three discordant for AS) and CD8+ T cell repertoires of three healthy HLA-B27+ individuals were characterized by TCR beta-chain (TCRB) CDR3 size spectratyping. Selected TCRB-CDR3 spectra were further analysed by BJ-segment analysis and TCRB-CDR3 from expanded T cell clones were sequenced. In an analysis of all data (519/598 possible TCRB-CDR3 spectra), AS was associated with increased T cell oligoclonality in both CD8+ (P = 0.0001) and CD4+ (P = 0.033) T cell subsets. This was also evident when data were compared between individual twins. Nucleotide sequence analysis of expanded CD8+ or CD4+ T cell clones did not show selection for particular TCRB-CDR3 amino acid sequence motifs but displayed sequence homologies with published sequences from intra-epithelial lymphocytes or synovial T cells from rheumatoid arthritis patients. Together, these results provide support for the hypothesis that responses to T cell-stimulating exogenous or endogenous antigens are involved in the induction and/or maintenance of AS. | |
| 11147173 | Distribution pattern of matrix metalloproteinases 1, 2, 3, and 9, tissue inhibitors of mat | 2000 Nov | Matrix metalloproteinases (MMPs) degrade basement membranes and connective tissue and play an essential role in the homeostasis of the extracellular matrix which is disrupted by the deposition of amyloid. This immunohistochemical study investigated the distribution pattern of matrix metalloproteinases (MMP-1, -2, -3, and -9) and their inhibitors [alpha 2-macroglobulin (alpha 2-M), tissue inhibitors of MMPs (TIMP)-1, and TIMP-2] in human AA- and AL amyloid deposits. Specimens of liver, kidney, and spleen from 22 autopsy cases were investigated. Nine patients had suffered from generalized AA amyloidosis, eight from generalized AL amyloidosis, and five from rheumatoid arthritis or tuberculosis with no histological evidence of amyloid. In all amyloidotic and non-amyloidotic patients, each protease and protease inhibitor was detected in almost every organ investigated. In the amyloidotic cases, there was no indication that a specific protease or protease inhibitor was absent or expressed, but a difference was observed in their spatial distribution patterns. The most noticeable difference was found in immunostaining of amyloid. Only MMP-1, -2, and -3, and alpha 2-M were present in AA amyloid deposits, and only TIMP-1 and TIMP-2 were found in deposits of AL amyloid. This is the first study to show that MMP-1, -2, and -3 are present in AA amyloid deposits. They may be involved in tissue remodeling or in proteolysis of the precursor and fibril proteins. | |
| 11110581 | Anti-centromere antibodies as a marker of Raynaud's phenomenon in pediatric rheumatologic | 2000 Nov | To examine the possible relationship between anti-centromere antibodies (ACA) and pediatric rheumatologic diseases, we investigated the presence of ACA (using enzyme immunoassay) in the sera of 45 children and adolescents with such diseases and compared the results with a group of 42 age- and gender-matched healthy subjects. ACA were present ( > or =10 U/ml) in three out of five patients (60%) with scleroderma (SCD), in seven out of 16 (43.8%) patients with systemic lupus erythematosus (SLE), in two out of five patients (40%) with mixed connective tissue disease (MCTD), in one out of four patients (25%) with dermatomyositis (DMS), and in two out of 14 patients (14.3%) with juvenile rheumatoid arthritis (JRA). ACA were also detected in a single patient with anti-phospholipid syndrome (APL) who had digital gangrene and hemiparesis, as well as in two healthy subjects. ACA positivity was related to the presence of Raynaud's phenomenon in the studied sample, as 86% of patients suffering from the phenomenon were ACA positive. ACA positivity was associated with older age, high blood pressure and high erythrocyte sedimentation rate (ESR) values, and lower hemoglobin and weight and height percentile values. It was also higher among anti-nuclear antibody-positive subjects. Raynaud's phenomenon and ACA positivity shared almost the same clinical and laboratory associations in the studied patients. Thus, ACA are probably among the markers of Raynaud's phenomenon in pediatric rheumatologic diseases. Their value as predictors of future development of the phenomenon needs further evaluation. | |
| 10930294 | Differential glycosylation of two glycoproteins synthesized by murine B cells in response | 2000 Aug | We sought to determine whether selected cytokines, known to stimulate profoundly B-cell activation and differentiation, also have as yet unrecognized effects upon the glycosylation of secreted Ig and/or membrane-associated proteins. The glycosylation of both secreted IgM and membrane-bound MHC Class-I synthesized by CH12LX cells was detected by enzyme-lectin conjugates in immunoabsorption assays. Stimulation of B cells with IL-4 plus IL-5 significantly decreases the terminal glycosylation of secreted IgM, whereas LPS has a minor effect, despite the fact that both stimuli are equipotent for IgM secretion. Neither LPS nor IL-4 plus IL-5 affect MHC Class-I expression. However, IL-4 plus IL-5 substantially increases the terminal glycosylation of MHC Class-I produced from both mIgM(+)and mIgA(+)CH12LX cells. LPS has no or a modest effect on the terminal glycosylation of MHC Class-I produced from CH12LX cells. These results suggest that Th(2)-derived cytokines differentially influence the glycosylation of secreted and membrane-associated glycoproteins of B cells. In turn, this might elucidate the basis of aberrant glycosylation reported in conditions such as IgA nephropathy, cancer and rheumatoid arthritis. | |
| 19078467 | Malignant neoplasms in autoimmune rheumatic diseases: examination of the risk of developin | 2000 Aug | Relationships between autoimmune rheumatic diseases and malignant neoplasms have been discussed, but there is no study of the different rheumatic diseases examining the risk of developing cancer. Our study has examined probabilities for developing malignancy among patients with connective tissue diseases seen in a single institution. Patients with autoimmune rheumatic disease and malignancy were compared with patients with the same autoimmune rheumatic diseases without malignancy. All cases identified through record-linkage from 1964 to 1996 were selected. Four controls per case were randomly selected from a pool of 3228 patients. The rheumatic diseases considered were rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), primary Sjögren's syndrome (pSS), dermatomyositis-polymyositis (DM-PM), and systemic sclerosis (Scl). The statistical analysis was conducted by conditional logistic regression, testing rheumatic disease as main effect. We identified 72 cases and 288 controls. Fifty-three of the cases had solid tumors, and 19 had lymphoproliferative neoplasms. The risk of developing a malignancy was considerably higher in DM-PM than in SLE (odds ratio [OR] = 17.5, 95% confidence interval [CI] 4.1-75.7), in pSS than in SLE (OR = 5.7, 95% CI 2.2-15.1), and in Scl than in SLE (OR = 5.4, 95% CI 1.6-18.0). These risks persisted after controlling for rheumatic disease duration, the time the disease was active, and anti-rheumatic treatment. RA had an OR of 1.8 (95% CI 0.9-3.4) with respect to SLE. This is the first study which describes the magnitude of risks among rheumatic diseases associated with the probability of developing a malignant neoplasm whether lymphoproliferative or solid. The risks in this series depend on the primary rheumatic disease, with DM-PM, pSS, and Scl all having greater risk than SLE. | |
| 10841792 | Peptide and peptide mimetic inhibitors of antigen presentation by HLA-DR class II MHC mole | 2000 Jun 1 | Molecular features of ligand binding to MHC class II HLA-DR molecules have been elucidated through a combination of peptide structure-activity studies and structure-based drug design, resulting in analogues with nanomolar affinity in binding assays. Stabilization of lead compounds against cathepsin B cleavage by N-methylation of noncritical backbone NH groups or by dipeptide mimetic substitutions has generated analogues that compete effectively against protein antigens in cellular assays, resulting in inhibition of T-cell proliferation. Crystal structures of four ternary complexes of different peptide mimetics with the rheumatoid arthritis-linked MHC DRB10401 and the bacterial superantigen SEB have been obtained. Peptide-sugar hybrids have also been identified using a structure-based design approach in which the sugar residue replaces a dipeptide. These studies illustrate the complementary roles played by phage display library methods, peptide analogue SAR, peptide mimetics substitutions, and structure-based drug design in the discovery of inhibitors of antigen presentation by MHC class II HLA-DR molecules. |