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1.  Current Status, Goals, and Research Agenda for Outcome Measures Development in Behçet Syndrome: Report from OMERACT 2014 
The Journal of rheumatology  2015;42(12):2436-2441.
There is an unmet need for reliable, validated, and widely accepted outcomes and outcome measures for use in clinical trials in Behçet syndrome (BS). Our report summarizes initial steps taken by the Outcome Measures in Rheumatology (OMERACT) vasculitis working group toward developing a core set of outcome measures for BS according to the OMERACT methodology, including the OMERACT Filter 2.0, and discussions during the first meeting of the BS working group held during OMERACT 12 (2014).
During OMERACT 12, some of the important challenges in developing outcomes for BS were outlined and discussed, and a research agenda was drafted.
Among topics discussed were the advantages and disadvantages of a composite measure for BS that evaluates several organs/organ systems; bringing patients and physicians together for discussions about how to assess disease activity; use of organ-specific measures developed for other diseases; and the inclusion of generic, disease-specific, or organ-specific measures. The importance of incorporating patients’ perspectives, concerns, and ideas into outcome measure development was emphasized.
The planned research agenda includes conducting a Delphi exercise among physicians from different specialties that are involved in the care of patients with BS and among patients with BS, with the aim of identifying candidate domains and subdomains to be assessed in randomized clinical trials of BS, and candidate items for a composite measure. The ultimate goal of the group is to develop a validated and widely accepted core set of outcomes and outcome measures for use in clinical trials in BS.
PMCID: PMC4940045  PMID: 26373563
2.  Update on Outcome Measure Development for Large Vessel Vasculitis: Report from OMERACT 12 
The Journal of rheumatology  2015;42(12):2465-2469.
The rarity of large vessel vasculitis (LVV) is a major factor limiting randomized controlled trials in LVV, resulting in treatment choices in these diseases that are guided mainly by observational studies and expert opinion. Further complicating trials in LVV is the absence of validated and meaningful outcome measures. The Outcome Measures in Rheumatology (OMERACT) vasculitis working group initiated the Large Vessel Vasculitis task force in 2009 to develop data-driven, validated outcome tools for clinical investigation in LVV. This report summarizes the progress that has been made on a disease activity assessment tool and patient-reported outcomes in LVV as well as the group’s research agenda.
The OMERACT LVV task force brought an international group of investigators and patient research partners together to work collaboratively on developing outcome tools. The group initially focused on disease activity assessment tools in LVV. Following a systematic literature review, an international Delphi exercise was conducted to obtain expert opinion on principles and domains for disease assessment. The OMERACT vasculitis working group’s LVV task force is also conducting qualitative research with patients, including interviews, focus groups, and engaging patients as research partners, all to ensure that the approach to disease assessment includes measures of patients’ perspectives and that patients have input into the research agenda and process.
The preliminary results of both the Delphi exercise and the qualitative interviews were discussed at the OMERACT 12 (2014) meeting and the completion of the analyses will produce an initial set of domains and instruments to form the basis of next steps in the research agenda.
The research agenda continues to evolve, with the ultimate goal of developing an OMERACT-endorsed core set of outcome measures for use in clinical trials of LVV.
PMCID: PMC4668221  PMID: 26077399
Vasculitis large vessel; Takayasu arteritis; Giant cell arteritis Outcomes; 
3.  Association of Granulomatosis With Polyangiitis (Wegener’s) With HLA–DPB1*04 and SEMA6A Gene Variants Evidence From Genome-Wide Analysis 
Arthritis and rheumatism  2013;65(9):2457-2468.
To identify genetic determinants of granulomatosis with polyangiitis (Wegener’s) (GPA).
We carried out a genome-wide association study (GWAS) of 492 GPA cases and 1,506 healthy controls (white subjects of European descent), followed by replication analysis of the most strongly associated signals in an independent cohort of 528 GPA cases and 1,228 controls.
Genome-wide significant associations were identified in 32 single-nucleotide polymorphic (SNP) markers across the HLA region, the majority of which were located in the HLA–DPB1 and HLA–DPA1 genes encoding the class II major histocompatibility complex (MHC) DPβ chain 1 and DPα chain 1 proteins, respectively. Peak association signals in these 2 genes, emanating from SNPs rs9277554 (for DPβ chain 1) and rs9277341 (DPα chain 1) were strongly replicated in an independent cohort (in the combined analysis of the initial cohort and the replication cohort, P = 1.92 × 10−50 and 2.18 × 10−39, respectively). Imputation of classic HLA alleles and conditional analyses revealed that the SNP association signal was fully accounted for by the classic HLA–DPB1*04 allele. An independent single SNP, rs26595, near SEMA6A (the gene for semaphorin 6A) on chromosome 5, was also associated with GPA, reaching genome-wide significance in a combined analysis of the GWAS and replication cohorts (P = 2.09 × 10−8).
We identified the SEMA6A and HLA–DP loci as significant contributors to risk for GPA, with the HLA–DPB1*04 allele almost completely accounting for the MHC association. These two associations confirm the critical role of immunogenetic factors in the development of GPA.
PMCID: PMC4471994  PMID: 23740775
4.  Pulmonary Fibrosis in Antineutrophil Cytoplasmic Antibodies (ANCA)-Associated Vasculitis 
Medicine  2014;93(24):340-349.
Pulmonary fibrosis (PF) is an uncommon manifestation observed in patients with antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV), particularly microscopic polyangiitis (MPA). While patients with PF associated with AAV seem to have a worse prognosis, these patients have been described only in case reports or small retrospective case series. In this retrospective multicenter study, we report the main features and long-term outcomes of patients with PF associated with AAV, fulfilling the American College of Rheumatology criteria and/or Chapel Hill definitions. Forty-nine patients (30 men [61%]; median age at diagnosis of AAV, 68 [interquartile range, 58–73] years) with PF associated with AAV were identified. Forty (81.6%) patients had MPA and 9 (18.4%) had granulomatosis with polyangiitis. The diagnosis of PF preceded the onset of vasculitis in 22 (45%) patients. Usual interstitial pneumonia was the main radiologic pattern (n = 18, 43%). ANCA were mostly of antimyeloperoxidase specificity (88%). All patients were treated with glucocorticoids as induction therapy, combined with cyclophosphamide (CYC) (n = 36, 73.5%) or rituximab (RTX) (n = 1, 2%). Factors associated with mortality included occurrence of chronic respiratory insufficiency (hazard ratio [HR], 7.44; 95% confidence interval [CI], 1.6–34.5; p = 0.003), induction therapy with glucocorticoids alone (HR, 2.94; CI, 1.05–8.33; p = 0.04), and initial weigh loss (HR, 2.83; CI, 1.05–7.65; p = 0.041). The 3-year survival rate in patients treated with glucocorticoids alone or combined with an immunosuppressant (CYC or RTX) as induction therapy was 64% (95% CI, 41–99) and 94% (95% CI, 86–100), respectively (p = 0.03). After a median follow-up of 48 months [interquartile range, 14–88 mo], 18 (37%) patients died, including 11 related to respiratory insufficiency. PF is a rare manifestation of AAV with a very poor prognosis. Induction therapy with CYC might improve the outcome.
PMCID: PMC4602438  PMID: 25500703
5.  Diagnosis and management of Neuro-Behçet’s disease: international consensus recommendations 
Journal of Neurology  2013;261(9):1662-1676.
Neuro-Behçet’s disease (NBD) is one of the more serious manifestations of Behçet’s disease (BD), which is a relapsing inflammatory multisystem disease with an interesting epidemiology. Though NBD is relatively uncommon, being potentially treatable, neurologists need to consider it in the differential diagnosis of inflammatory, infective, or demyelinating CNS disorders. Evidence-based information on key issues of NBD diagnosis and management is scarce, and planning for such studies is challenging. We therefore initiated this project to develop expert consensus recommendations that might be helpful to neurologists and other clinicians, created through an extensive literature review and wide consultations with an international advisory panel, followed by a Delphi exercise. We agreed on consensus criteria for the diagnosis of NBD with two levels of certainty in addition to recommendations on when to consider NBD in a neurological patient, and on the use of various paraclinical tests. The management recommendations included treatment of the parenchymal NBD and cerebral venous thrombosis, the use of disease modifying therapies, prognostic factors, outcome measures, and headache in BD. Future studies are needed to validate the proposed criteria and provide evidence-based treatments.
PMCID: PMC4155170  PMID: 24366648
Neuro-Behçet’s disease; Behçet’s disease; Delphi method; Consensus; Diagnosis; Management
6.  HLA–B51/B5 and the Risk of Behçet’s Disease: A Systematic Review and Meta-Analysis of Case–Control Genetic Association Studies 
Arthritis and rheumatism  2009;61(10):10.1002/art.24642.
To quantify by meta-analysis the genetic effect of the HLA–B5 or HLA–B51 (HLA–B51/B5) allele on the risk of developing Behçet’s disease (BD) and to look for potential effect modifiers.
Relevant studies were identified using the PubMed Medline database and manual searches of the literature. Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated by using the random-effects model. Subgroup meta-analyses and meta-regression analyses were undertaken to investigate the effects of selected study-level parameters on the pooled OR. Heterogeneity was assessed using the I2 statistic. Pooled results were used to calculate population-attributable risks (PAR) for BD in relationship to HLA–B51/B5.
A total of 4,800 patients with BD and 16,289 controls from 78 independent studies (published 1975–2007) were selected. The pooled OR of HLA–B51/B5 allele carriers to develop BD compared with noncarriers was 5.78 (95% CI 5.00–6.67), with moderate between-study heterogeneity (I2 = 61%). The subgroup analyses stratifying studies by geographic locations (Eastern Asia, Middle East/North Africa, Southern Europe, Northern/Eastern Europe) yielded consistent OR ranges (5.31–7.20), with I2 ranges of 52–70%. Univariate random-effects meta-regression indicated the percentage of male BD cases (P = 0.008) as a source of heterogeneity. The PAR within the various geographic areas were estimated at 32–52%.
The strength of the association between BD and HLA–B51/B5, and its consistency across populations of various ethnicities, lends further support to this allele being a primary and causal risk determinant for BD. Variations according to sex support an interaction of this allele with BD characteristics.
PMCID: PMC3867978  PMID: 19790126
7.  Meta-analysis in granulomatosis with polyangiitis reveals shared susceptibility loci with rheumatoid arthritis 
Arthritis and rheumatism  2012;64(10):3463-3471.
To examine the association of previously identified autoimmune disease susceptibility loci with granulomatosis with polyangiitis (GPA, formerly known as Wegener’s granulomatosis), and determine whether genetic susceptibility profiles of other autoimmune diseases are associated with GPA
Genetic data from two cohorts were meta-analyzed. Genotypes for 168 previously identified single nucleotide polymorphisms (SNPs) associated with susceptibility to different autoimmune diseases were ascertained for a total of 880 GPA cases and 1969 controls of European descent. Single marker associations were identified using additive logistic regression models. Multi-SNP associations with GPA were assessed using genetic risk scores based on susceptibility loci for Crohn’s disease, type 1 diabetes, systemic lupus erythematosus, rheumatoid arthritis, celiac disease, and ulcerative colitis. Adjustment for population substructure was performed in all analyses using ancestry informative markers and principal components analysis.
Genetic polymorphisms in CTLA4 were significantly associated with GPA in the single-marker meta-analysis (OR 0.79. 95% CI 0.70–0.89, p=9.8×10−5). A genetic risk score based on rheumatoid arthritis susceptibility markers was significantly associated with GPA (OR 1.05 per 1-unit increase in genetic risk score, 95% CI 1.02–1.08, p=5.1×10−5).
Rheumatoid arthritis and GPA may arise from a similar genetic predisposition. Aside from CTLA4, other loci previously found to be associated with common autoimmune diseases were not statistically associated with GPA in this study.
PMCID: PMC3425721  PMID: 22508400
genetics; vasculitis; granulomatosis with polyangiitis; rheumatoid arthritis; CTLA4
8.  Value of ANCA measurements during remission to predict a relapse of ANCA-associated vasculitis—a meta-analysis 
Rheumatology (Oxford, England)  2011;51(1):100-109.
Objective. The value of repeated ANCA measurements among patients with an established diagnosis of ANCA-associated vasculitis (AAV) remains controversial. The aim of this study was to explore whether either of the two distinct patterns of ANCA values during remission, a rise in ANCA or persistently positive ANCA, predicted future relapse.
Methods. MEDLINE and EMBASE searches were performed. Studies with at least 10 subjects with AAV from which both sensitivity and specificity of a rise in ANCA and/or persistent ANCA for future disease relapse could be calculated were included. Likelihood ratios were calculated for each study and pooled to arrive at summary estimates. I2-values were calculated as a measure of heterogeneity and meta-regression was used to explore sources of heterogeneity.
Results. Nine articles on a rise in ANCA and nine articles on persistent ANCA were included. The summary estimates for positive likelihood ratio (LR+) and negative likelihood ratio (LR−) of a rise in ANCA during remission on subsequent relapse of disease were 2.84 (95% CI 1.65, 4.90) and 0.49 (95% CI 0.27, 0.87), respectively. The summary estimates for LR+ and LR− of persistent ANCA during remission for subsequent disease relapse were 1.97 (95% CI 1.43, 2.70) and 0.73 (95% CI 0.50, 1.06), respectively. There was substantial between-study heterogeneity, which was partially explained by the frequency of ANCA measurements.
Conclusion. Among patients with AAV, a rise in or persistence of ANCA during remission is only modestly predictive of future disease relapse. There is limited use to serial ANCA measurements during disease remission to guide treatment decisions for individual patients with AAV.
PMCID: PMC3276294  PMID: 22039267
vasculitis; anti-neutrophil cytoplasmic antibodies; biomarker
9.  Vasculitic emergencies in the intensive care unit: a special focus on cryoglobulinemic vasculitis 
Vasculitis is characterized by the infiltration of vessel walls by inflammatory leukocytes with reactive damage and subsequent loss of vessel integrity. The clinical course of systemic vasculitis may be punctuated by acute life-threatening manifestations that require intensive care unit (ICU) admission. Furthermore, the diagnosis may be established in the ICU after admission for a severe inaugural symptom, mostly acute respiratory failure. Among the systemic vasculitides, cryoglobulinemic vasculitis (CV) has been rarely studied in an ICU setting. Severe CV-related complications may involve the kidneys, lungs, heart, gut, and/or central nervous system. The diagnosis of CV in the ICU may be delayed or completely unrecognized. A high level of suspicion is critical to obtain a timely and accurate diagnosis and to initiate appropriate treatment. We describe severe acute manifestations of CV based on six selected patients admitted to our ICU. That all six patients survived suggests the benefit of prompt ICU admission of patients with severe CV.
PMCID: PMC3488028  PMID: 22812447
Cryoglobulinemia; Cryoglobulinemic vasculitis; Acute respiratory failure; Acute kidney injury; Vasculitis; Systemic disease
10.  Health related quality of life in patients with newly diagnosed anti-neutrophil cytoplasm antibody associated vasculitis 
Arthritis care & research  2011;63(7):1055-1061.
Anti-neutrophil cytoplasm antibody-associated vasculitis (AAV) can present with a broad spectrum of signs and symptoms. The relative effects of different manifestations on health related quality of life (HRQOL) is unknown.
We conducted an individual patient data meta-analysis of baseline Short Form 36 (SF-36) scores from four randomized controlled trials of patients with newly diagnosed AAV. We determined the associations between organ manifestations at trial entry and the SF-36 Physical Composite Score (PCS) and Mental Composite Score (MCS) using mixed effects models adjusted for demographic factors. Associations with each of the 8 domains of the SF-36 were further explored using multivariate multiple regression.
SF-36 data was available from 346 patients. Older age (−0.11 points/year; 95% Confidence Interval [CI] −0.21 to −0.012; p=0.029) and neurologic involvement (−5.84, p<0.001) at baseline were associated with lower Physical Composite Scores. Physical Function scores were the most affected and older age (−0.25 points per year, 95% Confidence Interval [CI] −0.38 to −0.11; p<0.001) scores and neurologic involvement (−8.48 points, 95% CI −12.90 to −4.06; p<0.001) had the largest effects. The MCS was negatively affected only by chest involvement (p=0.027) but this effect was not exerted in any particular domain.
HRQOL in patients with newly diagnosed AAV are complex and incompletely explained by their organ system manifestations.
PMCID: PMC3128179  PMID: 21452254
vasculitis; health related quality of life; short form 36; ANCA; Wegener’s Granulomatosis
11.  Alpha1-Antitrypsin Deficiency–Related Alleles Z and S and the Risk of Wegener’s Granulomatosis 
Arthritis and rheumatism  2010;62(12):3760-3767.
Deficiency of α1-antitrypsin (α1AT) may be a determinant of susceptibility to Wegener’s granulomatosis (WG). Several previous, mainly small, case–control studies have shown that 5–27% of patients with WG carried the α1AT deficiency Z allele. It is not clear whether the S allele, the other major α1AT deficiency variant, is associated with WG. This study investigated the relationship of the α1AT deficiency Z and S alleles with the risk of developing WG in a large cohort.
We studied the distribution of the α1AT deficiency alleles Z and S in 433 unrelated Caucasian patients with WG and 421 ethnically matched controls. Genotyping was performed using an allele discrimination assay. Results were compared between cases and controls using exact statistical methods.
Among the patients with WG, the allele carriage frequencies of Z and S were 7.4% and 11.5%, respectively. The frequencies of the 6 possible genotypes differed in a statistically significant manner between cases and controls (P = 0.01). The general genetic 2-parameter codominant model provided the best fit to the data. Compared with the normal MM genotype, the odds ratio (OR) for MZ or MS genotypes was 1.47 (95% confidence interval [95% CI] 0.98–2.22), and the OR for ZZ, SS, or SZ genotypes was 14.58 (95% CI 2.33–∞). ORs of similar direction and magnitude were observed within the restricted cohorts that excluded cases and controls carrying ≥1 Z or ≥1 S allele.
Both Z and S alleles display associations with risk of WG in a codominant genetic pattern. These findings strengthen the evidence of a causal link between α1AT deficiency and susceptibility to WG.
PMCID: PMC3123032  PMID: 20827781
12.  The effects of duration of glucocorticoid therapy on relapse rate in anti-neutrophil cytoplasm antibody associated vasculitis: A meta-analysis 
Arthritis care & research  2010;62(8):1166-1173.
Disease relapses are common for patients with anti-neutrophil cytoplasm antibody associated vasculitis (AAV). The role of low-dose glucocorticoids (GC) in relapse prevention is controversial. We undertook a systematic review and meta-analysis to determine if GC target doses influence relapses of AAV.
Medline, EMBASE and Cochrane databases were searched for observational studies and randomized controlled trials of treatment of AAV that included a predefined GC treatment plan. The association of GC target dose with the proportion of relapses in studies was assessed using meta-regression and multi-level generalized linear modeling.
Thirteen studies (983 patients) were identified for inclusion. There were no studies directly comparing GC regimens. We classified 288 patients as having a non-zero GC target dose by study end and 695 patients as having a zero GC target dose by study end. The pooled proportion of patients with a relapse was 36% (95% confidence interval [CI] 25 to 47%). GC regimen was the most significant variable explaining the variability between the proportions of patients with relapses. The proportion of patients with a relapse was 14% (95% CI 10 to 19%) in non-zero GC target dose and 43% (95% CI 33 to 52%) in zero GC target dose studies. Differences other than GC regimens exist between studies that complicate the comparability of trials and isolation of the variability in relapses due to GC target alone.
Studies with longer courses of GC in AAV are associated with fewer relapses. These results have implications for study design and outcome assessment in clinical trials of AAV.
PMCID: PMC2946200  PMID: 20235186
anti-neutrophil cytoplasm antibodies; vasculitis; prednisolone; prednisone; Wegener’s granulomatosis
13.  Progress Towards a Core Set of Outcome Measures in Small-vessel Vasculitis. Report from OMERACT 9 
The Journal of rheumatology  2009;36(10):2362-2368.
The past decade has seen a substantial increase in the number and quality of clinical trials of new therapies for vasculitis, including randomized, controlled, multicenter trials that have successfully incorporated measures of disease activity and toxicity. However, because current treatment regimens for severe disease effectively induce initial remission and reduce mortality, future trials will focus on any of several goals including: (a) treatment of mild—moderate disease; (b) prevention of chronic damage; (c) reduction in treatment toxicity; or (d) more subtle differences in remission induction or maintenance. Thus, new trials will require outcome measure instruments that are more precise and are better able to detect effective treatments for different disease states and measure chronic manifestations of disease. The OMERACT Vasculitis Working Group comprises international clinical investigators with expertise in vasculitis who, since 2002, have worked collaboratively to advance the refinement of outcome measures in vasculitis, create new measures to address domains of illness not covered by current research approaches, and harmonize outcome assessment in vasculitis. The focus of the OMERACT group to date has been on outcome measures in small-vessel vasculitis with an overall goal of creating a core set of outcome measures for vasculitis, each of which fulfills the OMERACT filter of truth, discrimination, feasibility, and identifying additional domains requiring further research. This process has been informed by several ongoing projects providing data on outcomes of disease activity, disease-related damage, multidimensional health-related quality of life, and patient-reported ratings of the burden of vasculitis.
PMCID: PMC3142467  PMID: 19820226
14.  EULAR recommendations for conducting clinical studies and/or clinical trials in systemic vasculitis: focus on anti‐neutrophil cytoplasm antibody‐associated vasculitis 
Annals of the Rheumatic Diseases  2006;66(5):605-617.
To develop the European League Against Rheumatism (EULAR) recommendations for conducting clinical studies and/or clinical trials in systemic vasculitis.
An expert consensus group was formed consisting of rheumatologists, nephrologists and specialists in internal medicine representing five European countries and the USA, a clinical epidemiologist and representatives from regulatory agencies. Using an evidence‐based and expert opinion‐based approach in accordance with the standardised EULAR operating procedures, the group identified nine topics for a systematic literature search through a modified Delphi technique. On the basis of research questions posed by the group, recommendations were derived for conducting clinical studies and/or clinical trials in systemic vasculitis.
Based on the results of the literature research, the expert committee concluded that sufficient evidence to formulate guidelines on conducting clinical trials was available only for anti‐neutrophil cytoplasm antibody‐associated vasculitides (AAV). It was therefore decided to focus the recommendations on these diseases. Recommendations for conducting clinical trials in AAV were elaborated and are presented in this summary document. It was decided to consider vasculitis‐specific issues rather than general issues of trial methodology. The recommendations deal with the following areas related to clinical studies of vasculitis: definitions of disease, activity states, outcome measures, eligibility criteria, trial design including relevant end points, and biomarkers. A number of aspects of trial methodology were deemed important for future research.
On the basis of expert opinion, recommendations for conducting clinical trials in AAV were formulated. Furthermore, the expert committee identified a strong need for well‐designed research in non‐AAV systemic vasculitides.
PMCID: PMC2703775  PMID: 17170053
15.  Development and validation of a consensus methodology for the classification of the ANCA-associated vasculitides and polyarteritis nodosa for epidemiological studies 
Annals of the Rheumatic Diseases  2006;66(2):222-227.
The classification of antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and polyarteritis nodosa (PAN) for epidemiology studies is confusing. The existing schemes such as American College of Rheumatology (ACR) criteria, Chapel Hill Consensus Conference (CHCC) definitions and Lanham criteria produce overlapping and conflicting classifications, making it difficult to compare incidence figures.
To develop a consensus method of using these criteria and definitions for epidemiological studies to permit comparison without confounding by classification.
A stepwise algorithm was developed by consensus between a group of doctors interested in the epidemiology of vasculitis. The aim was to categorise patients with Wegener's granulomatosis, microscopic polyangiitis (MPA), Churg–Strauss syndrome (CSS) and PAN into single clinically relevant categories. The ACR and Lanham criteria for CSS, and ACR criteria for Wegener's granulomatosis were applied first, as these were considered to be the most specific. Surrogate markers for Wegener's granulomatosis were included to distinguish Wegener's granulomatosis from MPA. MPA was classified using the CHCC definition and surrogate markers for renal vasculitis. Finally, PAN was classified using the CHCC definition. The algorithm was validated by application to 20 cases from each centre and 99 from a single centre, followed by a paper case exercise.
A four-step algorithm was devised. It successfully categorises patients into a single classification. There was good correlation between observers in the paper case exercise (91.5%; unweighted κ = 0.886).
The algorithm achieves its aim of reliably classifying patients into a single category. The use of the algorithm in epidemiology studies should permit comparison between geographical areas.
PMCID: PMC1798520  PMID: 16901958

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