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Dive into the research topics where Mark C. Fisher is active.

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Featured researches published by Mark C. Fisher.


The American Journal of Medicine | 2011

Prevalence of Contraindications and Prescription of Pharmacologic Therapies for Gout

Robert T. Keenan; William R. O'Brien; Kristen Lee; Daria B. Crittenden; Mark C. Fisher; David S. Goldfarb; Svetlana Krasnokutsky; Cheongeun Oh; Michael H. Pillinger

BACKGROUND Patients with gout have comorbidities, but the impact of these comorbidities on treatment has not been studied. METHODS A total of 575 patients with gout were stratified according to certainty of diagnosis according to International Classification of Diseases, 9th Revision, Clinical Modification code alone (cohort I), American College of Radiology criteria (cohort II), and crystal diagnosis (cohort III). Comorbid conditions were defined according to International Classification of Diseases, 9th Revision, Clinical Modification codes, and stratified as either moderate or severe. Drug contraindications were defined as moderate or strong, based on Food and Drug Administration criteria and severity of disease. RESULTS The most common comorbidity was hypertension (prevalence 0.89). The presence of comorbidities resulted in a high frequency of contraindications to approved gout medications. More than 90% of patients had at least 1 contraindication to nonsteroidal anti-inflammatory drugs. Many patients demonstrated multiple contraindications to 1 or more gout medications. Frequently, patients were prescribed medications to which they harbored contraindications. The prevalence of patients prescribed colchicine despite having at least 1 strong contraindication was 30% (cohort I), 37% (cohort II), and 39.6% (cohort III). CONCLUSION Patients with gout typically harbor multiple comorbidities that result in contraindications to many of the medications available to treat gout. Frequently, despite contraindications to gout therapies, patients are frequently prescribed these medications.


The Journal of Rheumatology | 2009

Metaanalysis of methylenetetrahydrofolate reductase (MTHFR) polymorphisms affecting methotrexate toxicity.

Mark C. Fisher; Bruce N. Cronstein

Objective. Methotrexate (MTX) is an effective therapy for rheumatoid arthritis (RA) but it is also associated with toxicity. Pharmacogenetics is the systematic evaluation of the role of genetic differences in the efficacy and toxicity of therapeutic interventions. Because the results of small pharmacogenetic studies are often misleading, we undertook a metaanalysis of published studies to determine the role of polymorphisms in the therapeutic efficacy and toxicity of MTX. Methods. A search of PubMed produced 55 publications, which were then reviewed for relevance to MTX toxicity and efficacy in patients with RA. To ensure that no study was missed, each polymorphism found was then entered as an independent search string and all results were reviewed again. Results. Only 2 polymorphisms [C677T and A1298C in methylenetetrahydrofolate reductase (MTHFR); total 8 studies] relevant to MTX metabolism and efficacy had sufficient data to allow a metaanalysis of their association with toxicity; there was no polymorphism with sufficient data to perform a metaanalysis of efficacy. In a fixed-effects model, the C677T polymorphism was associated with increased toxicity (OR 1.71, 95% CI 1.32–2.21, p < 0.001). The A1298C polymorphism was not associated with increased toxicity (OR 1.12, 95% CI 0.79–1.6, p = 0.626). Conclusion. As pharmacogenetics evolves, more data are needed to assess the role of various polymorphisms for drug efficacy and toxicity. These results illustrate the paucity of reliable pharmacogenetic data on a commonly used antirheumatic drug and the potential role of pharmacogenetics in tailoring drug therapy for an individual patient.


Seminars in Arthritis and Rheumatism | 2014

Comparative cancer risk associated with methotrexate, other non-biologic and biologic disease-modifying anti-rheumatic drugs

Daniel H. Solomon; Joel M. Kremer; Mark C. Fisher; Jeffrey R. Curtis; Victoria Furer; Leslie R. Harrold; Marc C. Hochberg; George W. Reed; Peter Tsao; Jeffrey D. Greenberg

OBJECTIVE There is little information comparing the potential risk of cancer across conventional and biologic disease-modifying anti-rheumatic drugs (DMARDs) in patients with rheumatoid arthritis (RA). Methotrexate has not been the focus of most contemporary pharmacoepidemiologic studies of cancer. METHODS We conducted a comparative effectiveness study with cancer as the outcome. A large observational cohort of RA was followed up from 2001 to 2010. Reports of any cancer prompted a confirmation process that included adjudication of the primary cancer records. We used a propensity score (PS) with relevant covariates and cohort trimming to improve the balance between DMARD cohorts. Cox proportional hazard regression models were constructed to estimate the risk of cancer with various DMARDs, all compared with methotrexate. RESULTS We identified 6806 DMARD courses for analysis (1566 methotrexate; 904 nbDMARDs; 3761 TNF antagonists; 408 abatacept; and 167 rituximab). Non-biologic DMARDs (HR 0.17, 95% CI 0.05-0.65) and TNF antagonists (HR 0.29, 95% CI 0.05-0.65) were associated with a reduced adjusted risk of cancer compared with methotrexate. Abatacept (HR 1.55, 95% CI 0.40-5.97) and rituximab (HR 0.42, 95% CI 0.07-2.60) were similar in risk of cancer with methotrexate. These results were robust to sensitivity analyses. After controlling for DMARD exposures, risk factors for cancer included male gender, age, and alcohol consumption. CONCLUSIONS Cancer risk was elevated for methotrexate users compared with nbDMARDs and TNF antagonists.


Journal of Biomolecular Structure & Dynamics | 2011

Screening from the world's largest tcm database against h1n1 virus

Tung Ti Chang; Mao-Feng Sun; Hsin-Yi Chen; Fuu Jen Tsai; Mark C. Fisher; Jaung Geng Lin; Calvin Yu-Chian Chen

Abstract The swine influenza virus (H1N1) 2009 pandemic highlights the importance of having effective anti-viral strategies. Recently, oseltamivir (Tamiflu) resistant influenza viruses are identified; which further emphasizes the urgency in developing new antiviral agents. In influenza virus replication cycle, viral surface glycoprotein, hemagglutinin, is responsible for viral entry into host cells. Hence, a potentially effective antiviral strategy is to inhibit viral entry mechanism. To develop novel antiviral agent that inhibits viral entry, we analyzed 20,000 traditional Chinese medicine (TCM) ingredients in hemagglutinin subtype H1 sialic acid binding site found on H1N1 virus. We then performed molecular dynamics simulations to investigate receptor-ligand interaction of the candidates obtained from docking. Here, we report three TCM derivatives that have high binding affinities to H1 sialic acid binding site residues based on structure-based calculations. The top three derivatives, xylopine_2, rosmaricine_14 and rosmaricine_15, all have an amine group that interact with Glu83 and a pyridinium group that interact with Asp103. Molecular dynamics simulations show that these derivatives form strong hydrogen bonding with Glu83 but interact transiently with Asp103. We therefore suggest that an enhanced hemagglutinin inhibitor, based on our scaffold, should be designed to bind both Glu83 and Asp103 with high affinity.


Current Reviews in Musculoskeletal Medicine | 2011

Inflammatory bowel disease associated arthropathy

Sheila L. Arvikar; Mark C. Fisher

Arthritis is the most common extraintestinal manifestation of inflammatory bowel disease (IBD) and can have a significant impact on morbidity and quality of life. IBD-associated arthropathy is considered a subtype of seronegative spondyloarthropathy, with axial, peripheral, or a combination of both joint manifestations. Peripheral arthritis is generally non-erosive and the oligoarticular variant particularly may correlate with intestinal disease activity. Axial arthritis may include inflammatory back pain, sacroiliitis, or ankylosing spondylitis, and is less likely to correlate with gastrointestinal symptoms. While there have been advances in identifying predisposing genetic factors and in elucidating pathophysiology of inflammatory bowel disease, the mechanisms surrounding the development of arthritis in IBD remain unclear. Treatment of inflammatory bowel disease is not always sufficient for control of arthritis. While treatment with biologic agents is promising, there remains a great need for larger, randomized studies to address optimal therapy of IBD associated arthropathy.


Journal of Biomolecular Structure & Dynamics | 2011

Potent Inhibitor Design Against H1N1 Swine Influenza: Structure-based and Molecular Dynamics Analysis for M2 Inhibitors from Traditional Chinese Medicine Database

Chia Hui Lin; Tung Ti Chang; Mao-Feng Sun; Hsin-Yi Chen; Fuu Jen Tsai; Kun Lung Chang; Mark C. Fisher; Calvin Yu-Chian Chen

Abstract The rapid spread of influenza virus subtype H1N1 poses a great threat to million lives worldwide. To search for new anti-influenza compounds, we performed molecular docking and molecular dynamics simulation to identify potential traditional Chinese medicine (TCM) constituents that could block influenza M2 channel activity. Quinic acid, genipin, syringic acid, cucurbitine, fagarine, and methyl isoferulate all have extremely well docking results as compared to control amantadine. Further de novo drug design suggests that derivatives of genipin and methyl isoferulate could have enhanced binding affinity towards M2 channel. Selected molecular dynamics simulations of M2-derivative complexes show stable hydrogen bond interactions between the derivatives and M2 residues, Ser10 and Ala9. To our best knowledge, this is the first study on the anti-viral activity of the above listed TCM compounds.


Arthritis Research & Therapy | 2013

Clinical correlations with Porphyromonas gingivalis antibody responses in patients with early rheumatoid arthritis

Sheila L. Arvikar; Deborah S. Collier; Mark C. Fisher; Sebastian Unizony; George L. Cohen; Gail McHugh; Toshihisa Kawai; Klemen Strle; Allen C. Steere

IntroductionPrior studies have demonstrated an increased frequency of antibodies to Porphyromonas gingivalis (Pg), a leading agent of periodontal disease, in rheumatoid arthritis (RA) patients. However, these patients generally had long-standing disease, and clinical associations with these antibodies were inconsistent. Our goal was to examine Pg antibody responses and their clinical associations in patients with early RA prior to and after disease-modifying antirheumatic drug (DMARD) therapy.MethodsSerum samples from 50 DMARD-naïve RA patients were tested using an enzyme-linked immunosorbent assay with whole-Pg sonicate. For comparison, serum samples were tested from patients with late RA, patients with other connective tissue diseases (CTDs), age-similar healthy hospital personnel and blood bank donors. Pg antibody responses in early RA patients were correlated with standard RA biomarkers, measures of disease activity and function.ResultsAt the time of enrollment, 17 (34%) of the 50 patients with early RA had positive immunoglobulin G (IgG) antibody responses to Pg, as did 13 (30%) of the 43 patients with late RA. RA patients had significantly higher Pg antibody responses than healthy hospital personnel and blood bank donors (P < 0.0001). Additionally, RA patients tended to have higher Pg antibody reactivity than patients with other CTDs (P = 0.1), and CTD patients tended to have higher Pg responses than healthy participants (P = 0.07). Compared with Pg antibody-negative patients, early RA patients with positive Pg responses more often had anti-cyclic citrullinated peptide (anti-CCP) antibody reactivity, their anti-CCP levels were significantly higher (P = 0.03) and the levels of anti-Pg antibodies correlated directly with anti-CCP levels (P < 0.01). Furthermore, at the time of study entry, the Pg-positive antibody group had greater rheumatoid factor values (P = 0.04) and higher inflammatory markers (erythrocyte sedimentation rate, or ESR) (P = 0.05), and they tended to have higher disease activity scores (Disease Activity Score based on 28-joint count (DAS28)-ESR and Clinical Disease Activity Index) and more functional impairment (Health Assessment Questionnaire). In Pg-positive patients, greater disease activity was still apparent after 12 months of DMARD therapy.ConclusionsA subset of early RA patients had positive Pg antibody responses. The responses correlated with anti-CCP antibody reactivity and to a lesser degree with ESR values. There was a trend toward greater disease activity in Pg-positive patients, and this trend remained after 12 months of DMARD therapy. These findings are consistent with a role for Pg in disease pathogenesis in a subset of RA patients.


The Journal of Rheumatology | 2010

Comparative Analysis of Disease Activity Measures, Use of Biologic Agents, Body Mass Index, Radiographic Features, and Bone Density in Psoriatic Arthritis and Rheumatoid Arthritis Patients Followed in a Large U.S. Disease Registry

Soumya M. Reddy; Allen Anandarajah; Mark C. Fisher; Philip J. Mease; Jeffrey D. Greenberg; Joel M. Kremer; George W. Reed; Rui Chen; Susan Messing; Kimberly Kaukeinen; Christopher T. Ritchlin

Objective. To compare disease activity, radiographic features, and bone density in psoriatic arthritis (PsA) and rheumatoid arthritis (RA) matched cohorts. Methods. Disease activity and radiographic data in the Consortium of Rheumatology Researchers of North America database from 2001 to 2008 were compared for 2481 patients with PsA and 17,107 patients with RA subsequently matched for age, gender, and disease duration. Radiographic outcomes included presence of erosions, and joint deformity. In addition, bone mineral density (BMD) scores for lumbar spine (L-spine) and femoral neck were compared using the same matching criteria plus weight and smoking status. Results. Tender (4.5 vs 3.4, p < 0.001) and swollen (4.4 vs 2.9, p < 0.012) joint counts, and modified Health Assessment Questionnaire scores were significantly higher (0.4 vs 0.3, p < 0.001) in patients with RA compared with patients with PsA. Patient general health and pain scores were also higher in patients with RA vs patients with PsA. Joint erosions (47.4% vs 37.6%, p = 0.020) and deformity (25.2% vs 21.6%, p = 0.021) were more prevalent in RA than PsA. In multivariate analysis, a reduced prevalence of erosions in PsA vs RA was noted (OR 0.609, p < 0.001). After matching, T-scores for L-spine (−0.54 vs −0.36, p = 0.077) and femoral neck (−0.88 vs −0.93, p = 0.643) were similar in patients with RA and patients with PsA, although body weight was a major confounder. Conclusion. The level of disease activity and radiographic damage was significantly higher for RA vs PsA subjects, although the magnitude of differences was relatively small. BMD levels were comparable between cohorts. Outcomes in patients with PsA and patients with RA may be more similar than previously reported.


The Journal of Rheumatology | 2012

Smoking, Smoking Cessation, and Disease Activity in a Large Cohort of Patients with Rheumatoid Arthritis

Mark C. Fisher; Marc C. Hochberg; Muhammad El-Taha; Joel M. Kremer; Cheng Peng; Jeffrey D. Greenberg

Objective. While cigarette smoking is the best-studied environmental factor contributing to rheumatoid arthritis (RA), no study to date has examined the influence of smoking cessation on disease activity. We examined this relationship in an observational cohort of patients with RA in the United States. Methods. Patients enrolled in the Consortium of Rheumatology Researchers of North America registry (CORRONA) were stratified into never, former, and current smokers at enrollment. Current smokers were further stratified into continued and ceased smoking groups during their followup in the registry. The primary outcome was change in Clinical Disease Activity Index (CDAI) at last visit in a multivariate, random-effects regression model accounting for multiple timepoints. Results. At last visit, there was no significant change in CDAI between ceased smokers and continued smokers (coefficient −0.00091, SE 0.0033, p = 0.7834). The study did confirm prior cross-sectional studies that current smokers have worse disease activity than former or never smokers. Conclusion. In the short term, smoking cessation did not appear to influence change in disease activity over time.


JAMA | 2016

Trends in Gout and Rheumatoid Arthritis Hospitalizations in the United States, 1993-2011.

Sian Yik Lim; Na Lu; Amar Oza; Mark C. Fisher; Sharan K Rai; Mariano E. Menendez; Hyon K. Choi

This population epidemiology study uses Nationwide Inpatient Sample data to describe trends in US hospitalizations for gout and rheumatoid arthritis between 1993 and 2011.

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George W. Reed

University of Massachusetts Medical School

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Michael H. Pillinger

United States Department of Veterans Affairs

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Na Lu

Harvard University

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