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Dive into the research topics where Murray Baron is active.

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Featured researches published by Murray Baron.


Arthritis & Rheumatism | 2013

2013 Classification Criteria for Systemic Sclerosis: An American College of Rheumatology/European League Against Rheumatism Collaborative Initiative

Frank J. A. van den Hoogen; Dinesh Khanna; Jaap Fransen; Sindhu R. Johnson; Murray Baron; Alan Tyndall; Marco Matucci-Cerinic; Raymond P. Naden; Thomas A. Medsger; Patricia Carreira; Gabriela Riemekasten; Philip J. Clements; Christopher P. Denton; Oliver Distler; Yannick Allanore; Daniel E. Furst; Armando Gabrielli; Maureen D. Mayes; Jacob M van Laar; James R. Seibold; László Czirják; Virginia D. Steen; Murat Inanc; Otylia Kowal-Bielecka; Ulf Müller-Ladner; Gabriele Valentini; Douglas J. Veale; Madelon C. Vonk; Ulrich A. Walker; Lorinda Chung

OBJECTIVE The 1980 American College of Rheumatology (ACR) classification criteria for systemic sclerosis (SSc) lack sensitivity for early SSc and limited cutaneous SSc. The present work, by a joint committee of the ACR and the European League Against Rheumatism (EULAR), was undertaken for the purpose of developing new classification criteria for SSc. METHODS Using consensus methods, 23 candidate items were arranged in a multicriteria additive point system with a threshold to classify cases as SSc. The classification system was reduced by clustering items and simplifying weights. The system was tested by 1) determining specificity and sensitivity in SSc cases and controls with scleroderma-like disorders, and 2) validating against the combined view of a group of experts on a set of cases with or without SSc. RESULTS It was determined that skin thickening of the fingers extending proximal to the metacarpophalangeal joints is sufficient for the patient to be classified as having SSc; if that is not present, 7 additive items apply, with varying weights for each: skin thickening of the fingers, fingertip lesions, telangiectasia, abnormal nailfold capillaries, interstitial lung disease or pulmonary arterial hypertension, Raynauds phenomenon, and SSc-related autoantibodies. Sensitivity and specificity in the validation sample were, respectively, 0.91 and 0.92 for the new classification criteria and 0.75 and 0.72 for the 1980 ACR classification criteria. All selected cases were classified in accordance with consensus-based expert opinion. All cases classified as SSc according to the 1980 ACR criteria were classified as SSc with the new criteria, and several additional cases were now considered to be SSc. CONCLUSION The ACR/EULAR classification criteria for SSc performed better than the 1980 ACR criteria for SSc and should allow for more patients to be classified correctly as having the disease.


Annals of the Rheumatic Diseases | 2013

2013 classification criteria for systemic sclerosis: an American college of rheumatology/European league against rheumatism collaborative initiative

Frank J. A. van den Hoogen; Dinesh Khanna; Jaap Fransen; Sindhu R. Johnson; Murray Baron; Alan Tyndall; Marco Matucci-Cerinic; Raymond P. Naden; Thomas A. Medsger; Patricia Carreira; Gabriela Riemekasten; Philip J. Clements; Christopher P. Denton; Oliver Distler; Yannick Allanore; Daniel E. Furst; Armando Gabrielli; Maureen D. Mayes; Jacob M van Laar; James R. Seibold; László Czirják; Virginia D. Steen; Murat Inanc; Otylia Kowal-Bielecka; Ulf Müller-Ladner; Gabriele Valentini; Douglas J. Veale; Madelon C. Vonk; Ulrich A. Walker; Lorinda Chung

Objective The 1980 American College of Rheumatology (ACR) classification criteria for systemic sclerosis (SSc) lack sensitivity for early SSc and limited cutaneous SSc. The present work, by a joint committee of the ACR and the European League Against Rheumatism (EULAR), was undertaken for the purpose of developing new classification criteria for SSc. Methods Using consensus methods, 23 candidate items were arranged in a multicriteria additive point system with a threshold to classify cases as SSc. The classification system was reduced by clustering items and simplifying weights. The system was tested by (1) determining specificity and sensitivity in SSc cases and controls with scleroderma-like disorders, and (2) validating against the combined view of a group of experts on a set of cases with or without SSc. Results It was determined that skin thickening of the fingers extending proximal to the metacarpophalangeal joints is sufficient for the patient to be classified as having SSc; if that is not present, seven additive items apply, with varying weights for each: skin thickening of the fingers, fingertip lesions, telangiectasia, abnormal nailfold capillaries, interstitial lung disease or pulmonary arterial hypertension, Raynauds phenomenon, and SSc-related autoantibodies. Sensitivity and specificity in the validation sample were, respectively, 0.91 and 0.92 for the new classification criteria and 0.75 and 0.72 for the 1980 ACR classification criteria. All selected cases were classified in accordance with consensus-based expert opinion. All cases classified as SSc according to the 1980 ACR criteria were classified as SSc with the new criteria, and several additional cases were now considered to be SSc. Conclusions The ACR/EULAR classification criteria for SSc performed better than the 1980 ACR criteria for SSc and should allow for more patients to be classified correctly as having the disease.


BMJ Open | 2013

The Scleroderma Patient-centered Intervention Network (SPIN) Cohort: protocol for a cohort multiple randomised controlled trial (cmRCT) design to support trials of psychosocial and rehabilitation interventions in a rare disease context

Linda Kwakkenbos; Lisa R. Jewett; Murray Baron; Susan J. Bartlett; D.E. Furst; Karen Gottesman; Dinesh Khanna; Vanessa L. Malcarne; Maureen D. Mayes; Luc Mouthon; Serge Poiraudeau; Maureen Sauve; Warren R. Nielson; Janet L. Poole; Shervin Assassi; Isabelle Boutron; Carolyn Ells; Cornelia H. M. van den Ende; Marie Hudson; Ann Impens; Annett Körner; Catarina da Silva Correia Pereira Leite; Angela Costa Maia; Cindy Mendelson; Janet E. Pope; Russell Steele; Maria E. Suarez-Almazor; Sara Ahmed; Stephanie Coronado-Montoya; Vanessa C. Delisle

Introduction Psychosocial and rehabilitation interventions are increasingly used to attenuate disability and improve health-related quality of life (HRQL) in chronic diseases, but are typically not available for patients with rare diseases. Conducting rigorous, adequately powered trials of these interventions for patients with rare diseases is difficult. The Scleroderma Patient-centered Intervention Network (SPIN) is an international collaboration of patient organisations, clinicians and researchers. The aim of SPIN is to develop a research infrastructure to test accessible, low-cost self-guided online interventions to reduce disability and improve HRQL for people living with the rare disease systemic sclerosis (SSc or scleroderma). Once tested, effective interventions will be made accessible through patient organisations partnering with SPIN. Methods and analysis SPIN will employ the cohort multiple randomised controlled trial (cmRCT) design, in which patients consent to participate in a cohort for ongoing data collection. The aim is to recruit 1500–2000 patients from centres across the world within a period of 5 years (2013–2018). Eligible participants are persons ≥18 years of age with a diagnosis of SSc. In addition to baseline medical data, participants will complete patient-reported outcome measures every 3 months. Upon enrolment in the cohort, patients will consent to be contacted in the future to participate in intervention research and to allow their data to be used for comparison purposes for interventions tested with other cohort participants. Once interventions are developed, patients from the cohort will be randomly selected and offered interventions as part of pragmatic RCTs. Outcomes from patients offered interventions will be compared with outcomes from trial-eligible patients who are not offered the interventions. Ethics and dissemination The use of the cmRCT design, the development of self-guided online interventions and partnerships with patient organisations will allow SPIN to develop, rigourously test and effectively disseminate psychosocial and rehabilitation interventions for people with SSc.


Annals of the Rheumatic Diseases | 1982

The articular manifestations of progressive systemic sclerosis (scleroderma).

Murray Baron; P Lee; Edward C. Keystone

The articular manifestations of progressive systemic sclerosis (PSS) were studied in 38 patients. Of these, 66% experienced joint pain and 61% had signs of joint inflammation. Limitation of joint movement was seen in 45%. Radiological abnormalities included periarticular osteoporosis (42%), joint space narrowing (34%), and erosions (40%). Erosive disease did not correlate with disease duration, presence of rheumatoid factor, antinuclear antibodies, distal tuft resorption, or the extent of the scleroderma skin changes. Calcinosis was seen more frequently in those patients with articular erosions (67%). Erosive osteoarthritis of the distal interphalangeal joints (7 patients) was associated with impaired finger flexion. Joint involvement in PSS occurs frequently and may resemble rheumatoid arthritis in the early stages but is less destructive. The occurrence of unrelated arthropathy, such as primary osteoarthritis, is not uncommon, and its differentiation from true PSS joint disease can be difficult.


American Journal of Human Genetics | 2014

Immunochip Analysis Identifies Multiple Susceptibility Loci for Systemic Sclerosis

Maureen D. Mayes; Lara Bossini-Castillo; Olga Y. Gorlova; José Martín; Xiaodong Zhou; Wei Chen; Shervin Assassi; Jun Ying; Filemon K. Tan; Frank C. Arnett; John D. Reveille; Sandra G. Guerra; María Teruel; F. Carmona; Peter K. Gregersen; Annette Lee; Elena López-Isac; Eguzkine Ochoa; Patricia Carreira; Carmen P. Simeon; I. Castellví; Miguel A. González-Gay; Alexandra Zhernakova; Leonid Padyukov; Marta E. Alarcón-Riquelme; Cisca Wijmenga; Matthew A. Brown; Lorenzo Beretta; Gabriela Riemekasten; Torsten Witte

In this study, 1,833 systemic sclerosis (SSc) cases and 3,466 controls were genotyped with the Immunochip array. Classical alleles, amino acid residues, and SNPs across the human leukocyte antigen (HLA) region were imputed and tested. These analyses resulted in a model composed of six polymorphic amino acid positions and seven SNPs that explained the observed significant associations in the region. In addition, a replication step comprising 4,017 SSc cases and 5,935 controls was carried out for several selected non-HLA variants, reaching a total of 5,850 cases and 9,401 controls of European ancestry. Following this strategy, we identified and validated three SSc risk loci, including DNASE1L3 at 3p14, the SCHIP1-IL12A locus at 3q25, and ATG5 at 6q21, as well as a suggested association of the TREH-DDX6 locus at 11q23. The associations of several previously reported SSc risk loci were validated and further refined, and the observed peak of association in PXK was related to DNASE1L3. Our study has increased the number of known genetic associations with SSc, provided further insight into the pleiotropic effects of shared autoimmune risk factors, and highlighted the power of dense mapping for detecting previously overlooked susceptibility loci.


Arthritis & Rheumatism | 2009

MQX-503, a novel formulation of nitroglycerin, improves the severity of Raynaud's phenomenon: A randomized, controlled trial†

Lorinda Chung; Lee Shapiro; David Fiorentino; Murray Baron; Joseph Shanahan; Sangeeta Sule; Vivien M. Hsu; Naomi F. Rothfield; Virginia D. Steen; Richard W. Martin; Edwin A. Smith; Maureen D. Mayes; Robert W. Simms; Janet E. Pope; Bashar Kahaleh; Mary Ellen Csuka; Barry L. Gruber; David H. Collier; Nadera J. Sweiss; Adam Gilbert; Frederick J. Dechow; Jeffrey Gregory; Fredrick M. Wigley

OBJECTIVE Raynauds phenomenon (RP) affects 3-9% of the general population and >90% of patients with systemic sclerosis. Nitrates are often prescribed for the treatment of RP, but currently available formulations are limited by side effects, particularly headaches, dizziness, and skin irritation. The purpose of this study was to evaluate the tolerability and efficacy of a novel formulation of topical nitroglycerin, MQX-503, in the treatment of RP in an ambulatory setting. METHODS We conducted a multicenter, randomized, placebo-controlled study with a 2-week single-blind run-in period to determine baseline severity, followed by a 4-week double-blind treatment phase. Two hundred nineteen adult patients with a clinical diagnosis of primary or secondary RP received 0.9% MQX-503 gel or matching placebo during the treatment period. Gel was applied immediately before or within 5 minutes of the beginning of an episode of RP (maximum of 4 applications daily). End points included the change in the mean Raynauds Condition Score (RCS; scale 0-10), the frequency and duration of episodes, and subjective assessments at the target week (the week during the treatment phase that most closely matched the run-in period in terms of ambient temperature) compared with baseline. RESULTS The mean (%) change in the RCS at the target week compared with baseline was significantly greater in the MQX-503 group (0.48 [14.3%]) than that in the placebo group (0.04 [1.3%]; P = 0.04). Changes in the frequency and duration of RP episodes and subjective assessments were not statistically different between the groups. MQX-503 had a side effect profile similar to that of placebo. CONCLUSION MQX-503 is well tolerated and more effective than placebo for the treatment of RP.


Clinical Rheumatology | 2007

A comparison of the frequency of antibodies to cyclic citrullinated peptides using a third generation anti-CCP assay (CCP3) in systemic sclerosis, primary biliary cirrhosis and rheumatoid arthritis

Mittermayer Barreto Santiago; Murray Baron; Kiyomitsu Miyachi; Marvin J. Fritzler; Maysan Abu-Hakima; Sharon LeClercq; Mary Bell; Marie Hudson; Jean-Pierre Mathieu; Suzanne Taillefer; Niall Jones; Peter Docherty; Majed Khraishi; Janet Markland; Janet E. Pope; David Robinson; Douglas Smith; E. Sutton

The objective was to investigate the frequency of anti-cyclic citrullinated peptides (CCP) antibodies in systemic sclerosis (SSc) and primary biliary cirrhosis (PBC), utilizing a new “third generation” anti-CCP ELISA (anti-CCP3) kit and a conventional anti-CCP2 assay. Patients with PBC, SSc, RA, and normal controls were included in the study. Serum samples were screened for autoantibodies by indirect immunofluorescence (IIF), antibodies to CCP by a second- and third-generation ELISA, antibodies to “scleroderma” antigens (CENP B, Scl-70, PM/Scl and fibrillarin—Scl-34) by a line immunoassay (LIA), and IgM RF by ELISA. The frequency of anti-CCP2 antibodies in SSc and PBC samples was 14.8% (11/74) and 6.2% (5/80), respectively, and the frequency of anti-CCP3 antibodies in SSc was 13.5% (10/74) and in PBC was 3.7% (3/80). By comparison, in the RA group the frequency of anti-CCP3 and anti-CCP2 antibodies was 79.1% (38/48) and 77% (37/48), respectively. Anti-CCP3 ELISA had a sensitivity, specificity, and positive and negative likelihood ratios (LR) of 79% (95% confidence interval [CI] = 64–89%), 93% (95% CI = 88–96%), 11.8 (95% CI = 6.8–20.3), and 0.22 (95% CI = 0.12–0.38), respectively. By comparison, the anti-CCP2 assay had a sensitivity, specificity, and positive and negative LRs of 77% (95% CI = 62–87), 90% (95% CI = 85–94), 8.3 (95% CI = 5.2–13.2), and 0.25 (95% CI = 0.15–0.42), respectively. In patients with SSc, there was an association of anti-CCP2 antibodies with the presence of arthritis, but there was no association of anti-CCP2 or anti-CCP3 with anti-CENP B, anti-Scl 70, or RF. This study confirmed the high specificity and sensitivity of both anti-CCP assays for the diagnosis of RA. The presence of anti-CCP antibodies in SSc was only correlated with the presence of arthritis.


Arthritis Care and Research | 2009

Health-related quality of life in systemic sclerosis: A systematic review

Marie Hudson; Brett D. Thombs; Russell Steele; Pantelis Panopalis; Evan G. Newton; Murray Baron

OBJECTIVE A number of studies (all n <200) have assessed health-related quality of life (HRQOL) in patients with systemic sclerosis (SSc), but no systematic review of the effect of SSc on HRQOL has been done. The objective of this study was to systematically review the literature on HRQOL in SSc measured using the Medical Outcomes Trust Short Form 36 (SF-36). METHODS A comprehensive search was conducted in August 2007 using Medline, CINAHL, and EMBase to identify original research studies reporting SF-36 scores of SSc patients. Selected studies were reviewed and characteristics of the study samples and SF-36 data were extracted. Bayesian meta-analysis and meta-regression were performed to obtain pooled estimates of SF-36 physical component summary (PCS) and mental component summary (MCS) scores for all patients as well as by limited and diffuse disease status. RESULTS Twelve data sets with a total of 1,127 SSc patients were included in the systematic review. HRQOL was impaired in patients with SSc, with pooled SF-36 PCS scores being more than 1 SD below the general population (38.3; 95% credible interval [95% CI] 35.2, 41.5) and pooled SF-36 MCS scores being approximately 0.5 SDs below the general population (46.6; 95% CI 44.2, 49.1). SF-36 PCS scores were 3.5 points (95% CI -1.0, 8.0) lower in patients with diffuse compared with limited disease. CONCLUSION This study provides robust evidence of the presence and magnitude of impairment in HRQOL in patients with SSc. Although the impairment appears greater in physical health, mental health impairment is also reported.


Journal of Autoimmunity | 2008

Polyautoimmunity and familial autoimmunity in systemic sclerosis.

Marie Hudson; Adriana Rojas-Villarraga; Paola Coral-Alvarado; Silvia López-Guzmán; Rubén D. Mantilla; Philippe Chalem; Murray Baron; Juan-Manuel Anaya

Characterization of the extent to which particular combinations of autoimmune diseases occur in excess of that expected by chance may offer new insights into possible common pathophysiological mechanisms. The goal of this study was to investigate the spectrum of polyautoimmunity (i.e. autoimmune diseases co-occurring within patients) and familial autoimmunity (i.e. diverse autoimmune diseases co-occurring within families) in patients with systemic sclerosis (SSc). A cross-sectional study of two convenience samples of patients with SSc, one in Canada and the other in Colombia, was performed. History of other autoimmune diseases in the SSc patients as well as a family history of autoimmunity was obtained. Of 719 patients, 273 (38%) had at least one other autoimmune disease. A total of 366 autoimmune diseases were reported, of which the most frequent were autoimmune thyroid disease (AITD, 38%), rheumatoid arthritis (RA, 21%), Sjögrens syndrome (18%), and primary biliary cirrhosis (4%). There were 260 (36%) patients with first-degree relatives with at least one autoimmune disease, of which the most frequent were RA (18%) and AITD (9%). Having at least one first-degree relative with autoimmune disease was a significant predictor of polyautoimmunity in SSc patients. No significant differences in polyautoimmunity or familial autoimmunity were noted between diffuse and limited subsets of disease. Our results indicate that polyautoimmunity is frequent in patients with SSc and autoimmune diseases cluster within families of these patients. Clinically different autoimmune phenotypes might share common susceptibility variants, which acting in epistatic pleiotropy may represent risk factors for autoimmunity.


Arthritis Care and Research | 2011

Associations with digital ulcers in a large cohort of systemic sclerosis: Results from the Canadian Scleroderma Research Group registry

Sarit Khimdas; Sarah Harding; Ash Bonner; Brittany Zummer; Murray Baron; Janet E. Pope

Digital ulcers are a common complication of systemic sclerosis (SSc; scleroderma). Approximately half of SSc patients have had a digital ulcer, but information is lacking on whether digital ulcers are associated with patient demographics and clinical outcomes. We wanted to determine the associations between digital ulcers and other SSc vascular complications and organ involvement.

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Marie Hudson

Jewish General Hospital

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Janet E. Pope

University of Western Ontario

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Maureen D. Mayes

University of Texas Health Science Center at Houston

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Sasha Bernatsky

McGill University Health Centre

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