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Biomedical subjects

W J McCune

Publications and source records attributed to W J McCune.

At least 19 recordsLinked to original sources
PubMed2001

Decreased Ras-mitogen-activated protein kinase signaling may cause DNA hypomethylation in T lymphocytes from lupus patients.

OBJECTIVE: Previous studies have shown that inhibiting T cell DNA methylation causes a lupus-like disease by modifying gene expression. T cells from patients with lupus exhibit diminished levels of DNA methyltransferase (MTase) enzyme activity, hypomethylated DNA, and changes in gene expression similar to those exhibited by T cells treated with methylation inhibitors, suggesting that DNA hypomethylation may contribute to human lupus. Since it is known that DNA MTase levels are regulated by the ras-mitogen-activated protein kinase (MAPK) pathway, this study sought to determine whether decreased ras-MAPK signaling could account for the DNA hypomethylation in lupus T cells. METHODS: DNA MTase messenger RNA (mRNA) from lupus patients and from healthy controls was quantitated by Northern analysis, and ras-MAPK signaling was determined by immunoblotting with antibodies to the activated forms of extracellular receptor-associated kinase (ERK). Results were compared with those in T cells in which ras-MAPK signaling was inhibited with a soluble inhibitor of MAPK ERK I (MEK1). RESULTS: T cells from patients with active lupus had diminished DNA MTase mRNA levels and decreased signaling through the ras-MAPK pathway. Inhibiting signaling through the ras-MAPK pathway with the MEK1 inhibitor decreased DNA MTase mRNA and enzyme activity to the levels seen in lupus T cells, and resulted in DNA hypomethylation resembling that seen in lupus T cells. CONCLUSION: These results suggest that a decrease in signaling through the ras-MAPK pathway may be responsible for the decreased MTase activity and DNA hypomethylation in patients with lupus.

Adolescent↗
PubMed2000

Thrombosis in patients with connective tissue diseases treated with specific cyclooxygenase 2 inhibitors. A report of four cases.

Specific inhibitors of cyclooxygenase 2 (COX-2) have been approved for the treatment of osteoarthritis and rheumatoid arthritis. Unlike nonsteroidal anti-inflammatory drugs, specific COX-2 inhibitors do not inhibit platelet activation. However, these agents significantly reduce systemic production of prostacyclin. As a result, theoretical concerns have been raised that specific COX-2 inhibitors could shift the hemostatic balance toward a prothrombotic state. Patients with connective tissue diseases (CTD), who may be predisposed to vasculopathy and thrombosis, often have arthritis or pain syndromes requiring treatment with antiinflammatory agents. Herein we describe 4 patients with CTD who developed ischemic complications after receiving celecoxib. All patients had a history of Raynaud's phenomenon, as well as elevated anticardiolipin antibodies, lupus anticoagulant, or a history compatible with antiphospholipid syndrome. It was possible to measure a urinary metabolite of thromboxane A2 in 2 of the patients as an indicator of in vivo platelet activation, and this was markedly elevated in both. In addition, the patients had evidence of ongoing inflammation as indicated by elevated erythrocyte sedimentation rate, hypocomplementemia, and/or elevated levels of anti-DNA antibodies. The findings in these 4 patients suggest that COX-2 inhibitor-treated patients with diseases that predispose to thrombosis should be monitored carefully for this complication.

Adult↗
PubMed2000

Chimeric anti-tumor necrosis factor-alpha monoclonal antibody treatment of patients with rheumatoid arthritis receiving methotrexate therapy.

OBJECTIVE: To evaluate the safety and efficacy of single and multiple doses of a chimeric anti-TNF-alpha monoclonal antibody (infliximab) in patients with rheumatoid arthritis (RA) who had active disease despite therapy with methotrexate (MTX). METHODS: Twenty-eight patients with active RA despite receiving therapy with 10 mg/week of MTX were randomized to receive a single, blinded infusion of either placebo or 5, 10, or 20 mg/kg infliximab. Twenty-three patients who completed the blinded study entered an open, multiple dose extension study in which they received up to 3 additional infusions of 10 mg/kg infliximab at Weeks 12, 20, and 28. Safety, efficacy, and pharmacokinetics were evaluated during the blinded and open trial. RESULTS: There were no serious infusion related reactions. In the blinded phase, 17 (81.0%) of 21 patients receiving infliximab achieved an American College of Rheumatology (ACR) 20% response at some point during the 12 weeks of followup compared to one (14.3%) of 7 patients receiving placebo (p = 0.003). Clinical improvement was evident by the first week and was sustained through Week 12. For the 19 patients who received infliximab during the blinded part of the trial and continued into the open label trial, 53% maintained an ACR 20% response with multiple infusions of 10 mg/kg infliximab through Week 40. Three patients withdrew from the trial during the open continuation phase because of adverse events: cellulitis, infusion related dizziness and headache, and vasculitic rash. Infliximab in doses of 5 to 20 mg/kg had a mean terminal half-life ranging from 9 to 12 days and was detectable in sera from most patients 8 to 12 weeks after dosing. CONCLUSION: Infliximab is generally well tolerated during 40 weeks of therapy. A single infusion of 5 to 20 mg/kg infliximab significantly decreases the signs and symptoms of RA compared to placebo in patients with active disease receiving MTX. Multiple doses of infliximab produce sustained clinical benefit for up to 40 weeks.

Adult↗
PubMed1999

Prevention of infectious complications in rheumatic disease patients: immunization, Pneumocystis carinii prophylaxis, and screening for latent infections.

Most rheumatology textbooks lack adequate recommendations for specific immunization of patients with rheumatic diseases, especially those treated with immunosuppressive medications. The authors wish to alert clinicians to issues pertinent to immunization of immunosuppressed rheumatology patients. By elucidating deficiencies in the current literature, the authors hope to identify future directions for clinical investigation and to increase the rates of effective immunization against vaccine preventable diseases. In addition to focusing on immunizations, this article also discusses Pneumocystis carinii prophylaxis in immunosuppressed patients with rheumatic diseases and screening that clinicians should consider before beginning administration of immunosuppressive agents.

Bacterial Infections↗
PubMed1998

Cytogenetic abnormalities and therapy-related myelodysplastic syndromes in rheumatic disease.

OBJECTIVE: To describe the myelodysplastic syndromes (MDS) and cytogenetic abnormalities that occur in patients who have been treated with alkylating drugs for their rheumatic disease. METHODS: Patients with rheumatic disease who developed MDS after current or previous treatment with alkylating drugs were selected for evaluation by chart review and cytogenetic studies. RESULTS: Eight patients with rheumatic disease (mean age 56.9 years) developed MDS over the study period. Seven had received oral cyclophosphamide and 1 chlorambucil as their main immunosuppressive drug. The mean total cumulative dose of cyclophosphamide or chlorambucil was 118 gm and 6.5 gm, respectively, over a period of 2-10 years. The cytogenetic abnormalities included a deletion of all or part of chromosome 7 in 5 patients, while 4 had a deletion of part of the long arm of chromosome 5. Six of the patients have since died. CONCLUSION: Large cumulative doses of cyclophosphamide and chlorambucil were associated with the development of MDS, the occurrence of abnormalities of chromosome 5 and/or chromosome 7 deletions, and a poor prognosis.

Adult↗
PubMed1998

Update on immunosuppressive therapy.

In this review we summarize selected articles that have been published about immunosuppressive agents in the past year. These studies fall into three major categories: 1) use of pulse cyclophosphamide in autoimmune diseases other than systemic lupus erythematosus; 2) use of newer immunosuppressive agents such as cyclosporine and FK506 in a variety of rheumatic diseases; and 3) toxicity.

Adult↗
PubMed1996

A double-blind, placebo-controlled study of anti-CD5 immunoconjugate in patients with rheumatoid arthritis. The Xoma RA Investigator Group.

OBJECTIVE: To evaluate the efficacy of an anti-CD5 ricin-linked immunoconjugate (CD5-IC) in patients with rheumatoid arthritis (RA). METHODS: A total of 104 evaluable patients were enrolled in a multicenter, double-blind, multiple-dose, placebo-controlled study of CD5-IC. RESULTS: Treatment with CD5-IC in doses up to 8 mg/m2/day for 4 days in 1 month failed to produce marked or prolonged T cell depletion and was no more effective than placebo in ameliorating disease manifestations. An unexpectedly high placebo response was observed in 48% of the patients. Adverse events were correlated with the dose of CD5-IC, but the treatment was generally well-tolerated. CONCLUSION: At the doses used in this study, CD5-IC was ineffective for treating RA.

Adult↗
PubMed1996

Immunosuppressive drug therapy.

Intravenous cyclophosphamide therapy for autoimmune disease continues to be the subject of many clinical trials, which in general have strongly supported its use in lupus nephritis but have failed to demonstrate efficacy in severe vasculitis or severe Wegener's granulomatosis. A particularly difficult issue is the use of this medical therapy in neurologic disease. Uncertainty as to the patholophysiologic processes leading to development of neurologic symptoms, particularly in patients with systemic lupus, and difficulty in following response to clinical trials objectively have been associated with a relative lack of information about the efficacy of cyclophosphamide therapy. This review will focus on treatment of neurologic lupus and review the use of cyclophosphamide in multiple sclerosis as well.

Humans↗
PubMed1995

Immunosuppressive treatment of the pulmonary manifestations of progressive systemic sclerosis.

In this article, we review recent studies on the use of immunosuppressive agents in autoimmune diseases, especially cyclophosphamide. In addition, we begin with a special section on the treatment of scleroderma lung disease, including controversies regarding the indications for immunosuppressive therapy. Scleroderma lung disease is justifiably regarded as one of the "frontiers of medicine" because of its gravity, its often rapidly progressive nature, and the urgency with which improved therapy is needed.

Autoantibodies↗
PubMed1995

Sulfasalazine therapy for psoriatic arthritis: a double blind, placebo controlled trial.

OBJECTIVE: Psoriatic arthritis (PsA) is often poorly responsive to 2nd line antirheumatic drug therapy. Sulfasalazine has recently gained wide acceptance in the treatment of rheumatoid arthritis, and beneficial effects have also been noted in ankylosing spondylitis and reactive arthritis. We report a double blind placebo controlled study of sulfasalazine in PsA. METHODS: Twenty-four patients with active PsA were randomized to receive either sulfasalazine (3 g/day) (n = 10) or placebo (n = 14) for 8 weeks, in a double blind manner, followed by an 8 week open label crossover phase for nonresponding placebo patients. RESULTS: Compared with placebo controls, sulfasalazine treated patients were significantly improved at Weeks 4 and 8 with respect to physician (p < 0.01) and patient (p < 0.05) global assessments. Duration of morning stiffness was significantly decreased at Week 8 (p < 0.01). Clinical variables of disease activity returned to baseline after a 4 week drug washout period in 5 evaluable patients. Six patients in the placebo group crossed over to an 8 week open label phase and demonstrated significant improvements in joint scores, 50 ft walking time, and global patient assessment. Sulfasalazine treated patients also showed significant improvements in cutaneous involvement. CONCLUSION: Sulfasalazine was effective in PsA, with efficacy observed as early as the 4th week of treatment. Longterm studies are needed to determine whether such therapy can modify disease outcome.

Activities of Daily Living↗
PubMed1994

Immediate hypersensitivity reaction to cyclophosphamide.

We report a case of an acute anaphylactic reaction to intravenous cyclophosphamide in a patient with systemic lupus erythematosus. Skin testing for reactivity to cyclophosphamide and one of its metabolites, 4-hydroperoxycyclophosphamide, was performed on the patient and on 6 controls. The patient exhibited positive skin test responses; all controls had negative responses. The results suggest an acute hypersensitivity reaction related to sensitivity to cyclophosphamide and to 4-hydroperoxycyclophosphamide, through a shared antigenic determinant or dual sensitization.

Adult↗
PubMed1994

Immunosuppressive drug therapy.

Interstitial lung disease frequently complicates rheumatic disorders, especially polymyositis-dermatomyositis, rheumatoid arthritis, systemic sclerosis, and mixed connective tissue disease. In this article, we review the current data supporting the use of azathioprine, cyclophosphamide, chlorambucil, cyclosporine, and methotrexate in the management of chronic interstitial pneumonitis-fibrosis. The literature addressing the utility of these immunosuppressive-cytotoxic agents, however, consists almost entirely of anecdotal successes and small, uncontrolled series. Although no convincing data have proven that the use of any of these agents with or without corticosteroids is superior to therapy with corticosteroids alone, the literature may suggest a slight long-term survival advantage when either azathioprine or cyclophosphamide is added to prednisone therapy. Studies in which cyclosporine was used, however, have been less encouraging. Data regarding the use of chlorambucil and methotrexate are too sparse to permit any conclusions. Further controlled studies are required to clarify the role of these immunosuppressive agents in the treatment of interstitial lung disease.

Adrenal Cortex Hormones↗
PubMed1994

The role of methotrexate in the management of steroid-dependent asthma.

Severe asthma often requires high-dose corticosteroid therapy. However, steroid therapy is fraught with many side effects. There are conflicting reports in the literature regarding the role of methotrexate in reducing the steroid requirements of these patients. This study examined the role of low-dose methotrexate in the management of steroid-dependent asthma. Eleven subjects with stable steroid-dependent asthma were enrolled in a placebo-controlled double-blind crossover trial. Patients received methotrexate, 15 mg/wk, or placebo each for two 12-week periods. There was significant improvement of pulmonary function and reduction of prednisone requirement in both placebo and methotrexate treatment periods. However, methotrexate was not superior to placebo. Only 3 of 11 patients responded to methotrexate. Although low-dose methotrexate therapy may have a role in a small select group of steroid-dependent asthmatics, it provided no additional benefit overall.

Adolescent↗
PubMed1994

Lupus nephritis. Classification, prognosis, immunopathogenesis, and treatment.

There is great variation in the characteristics of renal histology, in its clinical expression and clinical course, and, most likely, in the pathogenic mechanisms of glomerular damage. As the ability to more precisely characterize these lesions improves and as we better understand the multiple pathogenic mechanisms and modulating factors at play in the disease, treatment advances and improved renal survival should follow.

Antibodies, Antinuclear↗