scholarly journals Clinical Relevance of the Serial Measurement of Krebs von den Lungen-6 Levels in Patients with Systemic Sclerosis-Associated Interstitial Lung Disease

Diagnostics ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2007
Author(s):  
Yuichiro Shirai ◽  
Ryosuke Fukue ◽  
Yuko Kaneko ◽  
Masataka Kuwana
Keyword(s):  
Systemic Sclerosis ◽  
Interstitial Lung Disease ◽  
Lung Disease ◽  
Topoisomerase I ◽  
Significant Proportion ◽  
High Resolution Computed Tomography ◽  
Extensive Disease ◽  
Serial Measurement ◽  
Level Measurement ◽  
Wide Range

Krebs von den Lungen-6 (KL-6) levels measured at baseline have been reported as a circulating biomarker useful for the detection, evaluation of severity and assessment of risk of the progression of interstitial lung disease (ILD) in patients with systemic sclerosis (SSc). In this retrospective study, longitudinal changes in serum KL-6 levels over 2 years were examined in 110 patients with SSc using prospectively collected cohort data. Serum KL-6 levels fluctuated in a significant proportion of the patients but remained stable in the remaining patients. A wide range of variability of longitudinal KL-6 levels was associated with the presence of ILD, diffuse cutaneous SSc, positive anti-topoisomerase I antibodies, negative anticentromere antibodies, increased ILD extent on high-resolution computed tomography, extensive disease, low pulmonary function parameters, high KL-6 levels at baseline and immunomodulatory treatment. Extensive disease was consistently identified as an independent factor associated with variability in KL-6 levels in different models of multiple regression analysis. We failed to demonstrate correlations between trends for KL-6 level changes during the 6 months after SSc diagnosis and ILD progression over 2 years in patients with SSc-ILD. Serum KL-6 levels fluctuate in SSc patients with ILD, especially in those with extensive disease, but the clinical utility of a serial KL-6 level measurement remains uncertain.

scholarly journals Predictors of progression in systemic sclerosis patients with interstitial lung disease

2020 ◽  
Vol 55 (5) ◽  
pp. 1902026 ◽  
Author(s):  
Oliver Distler ◽  
Shervin Assassi ◽  
Vincent Cottin ◽  
Maurizio Cutolo ◽  
Sonye K. Danoff ◽  
...  
Keyword(s):  
Systemic Sclerosis ◽  
Interstitial Lung Disease ◽  
Lung Disease ◽  
Disease Progression ◽  
Topoisomerase I ◽  
Diagnostic Tools ◽  
Systemic Autoimmune Disease ◽  
High Resolution Computed Tomography ◽  
Time Period ◽  
Organ Systems

Systemic sclerosis (SSc) is a systemic autoimmune disease affecting multiple organ systems, including the lungs. Interstitial lung disease (ILD) is the leading cause of death in SSc.There are no valid biomarkers to predict the occurrence of SSc-ILD, although auto-antibodies against anti-topoisomerase I and several inflammatory markers are candidate biomarkers that need further evaluation. Chest auscultation, presence of shortness of breath and pulmonary function testing are important diagnostic tools, but lack sensitivity to detect early ILD. Baseline screening with high-resolution computed tomography (HRCT) is therefore necessary to confirm an SSc-ILD diagnosis. Once diagnosed with SSc-ILD, patients' clinical courses are variable and difficult to predict, although certain patient characteristics and biomarkers are associated with disease progression. It is important to monitor patients with SSc-ILD for signs of disease progression, although there is no consensus about which diagnostic tools to use or how often monitoring should occur. In this article, we review methods used to define and predict disease progression in SSc-ILD.There is no valid definition of SSc-ILD disease progression, but we suggest that either a decline in forced vital capacity (FVC) from baseline of ≥10%, or a decline in FVC of 5–9% in association with a decline in diffusing capacity of the lung for carbon monoxide of ≥15% represents progression. An increase in the radiographic extent of ILD on HRCT imaging would also signify progression. A time period of 1–2 years is generally used for this definition, but a decline over a longer time period may also reflect clinically relevant disease progression.

scholarly journals AB0605 CLINICAL PROFILE AND CHEST HIGH-RESOLUTION COMPUTED TOMOGRAPHY (HRCT) FINDINGS IN PATIENTS WITH CONNECTIVE TISSUE DISEASES AND INTERSTITIAL LUNG DISEASE: EXPERIENCE OF A SINGLE REFERENCE RHEUMATOLOGY CENTER

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1598.2-1599
Author(s):  
I. Rusu ◽  
L. Muntean ◽  
M. M. Tamas ◽  
I. Felea ◽  
L. Damian ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Systemic Sclerosis ◽  
High Resolution ◽  
Interstitial Lung Disease ◽  
Connective Tissue ◽  
Lung Disease ◽  
Interstitial Pneumonia ◽  
Connective Tissue Diseases ◽  
High Resolution Computed Tomography ◽  
Hrct Patterns

Background:Interstitial lung disease (ILD) is a common manifestation of connective tissue diseases (CTDs), and is associated with significant morbidity and mortality. Chest high-resolution computed tomography (HRCT) play an important role in the diagnosis of ILD and may provide prognostic information.Objectives:We aimed to characterize the clinical profile and chest HRCT abnormalities and patterns of patients diagnosed with CTDs and ILD.Methods:In this retrospective, observational study we included 80 consecutive patients with CTDs and ILD referred to a tertiary rheumatology center between 2015 and 2019. From hospital charts we collected clinical data, immunologic profile, chest HRCT findings. HRCT patterns were defined according to new international recommendations.Results:Out of 80 patients, 64 (80%) were women, with a mean age of 55 years old. The most common CTD associated with ILD was systemic sclerosis (38.8%), followed by polymyositis (22.5%) and rheumatoid arthritis (18.8%). The majority of patients had dyspnea on exertion (71.3%), bibasilar inspiratory crackles were present in 56.3% patients and 10% had clubbing fingers. Antinuclear antibodies (ANA) were present in 78.8% patients, and the most frequently detected autoantibodies against extractable nuclear antigen were anti-Scl 70 (28.8%), followed by anti-SSA (anti-Ro, 17.5%), anti-Ro52 (11.3%) and anti-Jo (7.5%). Intravenous cyclophosphamide therapy for 6-12 months was used in 35% of patients, while 5% of patients were treated with mycophenolate mofetil.The most frequent HRCT abnormalities were reticular abnormalities and ground glass opacity. Non-specific interstitial pneumonia (NSIP) was identified in 46.3% CTDs patients. A pattern suggestive of usual interstitial pneumonia (UIP) was present in 32.5% patients, mainly in patients with systemic sclerosis. In 21.3% patients the HRCT showed reticulo-nodular pattern, micronodules and other abnormalities, not diagnostic for UIP or NSIP pattern.Conclusion:Nonspecific interstitial pneumonia (NSIP) is the most common HRCT pattern associated with CTDs. Further prospective longitudinal studies are needed in order to determine the clinical and prognostic significance of various HRCT patterns encountered in CTD-associated ILD and for better patient management.References:[1]Ohno Y, Koyama H, Yoshikaua T, Seki S. State-of-the-Art Imaging of the Lung for Connective Tissue Disease (CTD). Curr Rheumatol Rep. 2015;17(12):69.[2]Walsh SLF, Devaraj A, Enghelmeyer JI, Kishi K, Silva RS, Patel N, et al. Role of imaging in progressive-fibrosing interstitial lung diseases. Eur Respir Rev. 2018;27(150)Disclosure of Interests:None declared

scholarly journals POS0842 LUNG ULTRASOUND TO ASSESS THE SEVERITY OF INTERSTITIAL LUNG DISEASE IN SYSTEMIC SCLEROSIS

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 675.1-675
Author(s):  
C. Bruni ◽  
L. Mattolini ◽  
L. Tofani ◽  
L. Gargani ◽  
N. Landini ◽  
...  
Keyword(s):  
Systemic Sclerosis ◽  
Interstitial Lung Disease ◽  
Lung Disease ◽  
Quantitative Methods ◽  
Lung Ultrasound ◽  
Significant Negative Correlation ◽  
High Resolution Computed Tomography ◽  
Quantitative Score ◽  
Quantitative Scoring ◽  
B Lines

Background:Interstitial lung disease (ILD) is one of the most common complications and one of the main causes of morbidity and mortality in Systemic Sclerosis (SSc). High-resolution computed tomography (HRCT) is the gold standard for the diagnosis of ILD and it allows its quantification. Among semi-quantitative methods, Goh et al proposed a semi-quantitative scoring system to visually quantify ILD extent, with categorical cut-off of 20% to distinguish limited and extensive parenchymal involvement with prognostic implications. More recently, the use of radiomics has allowed the objective quantification of ILD through the use of dedicated software, which calculate different parameters of lung density.Given the exposure to ionizing radiation that the procedure entails, other methods of ILD evaluation are being studied, among which lung ultrasound (LUS) identifies the B-lines as a main feature of ILD. So far, different evidences have proposed the use of LUS for the screening of ILD, even in the early phases of the disease and in subclinical lung involvement.Objectives:the aim of this study is to test the role of LUS in quantifying the severity of SSc-ILD, evaluated with both semi-quantitative visual radiological and quantitative radiomic scores.Methods:Adult SSc patients classified according to the ACR/EULAR 2013 criteria patients were assessed with pulmonary function test (PFTs), lung ultrasound and HRCT over 60 days. CT images were analysed qualitatively (by presence/absence of ILD), semi-quantitatively (categorical Goh score <20% vs> 20% of extent and the continuous extent Goh score made from 5 levels’ assessment– 0 to 100%) and quantitatively [with the densitometric radiomic data obtained through the Horos software - Mean lung attenuation (MLA), Standard Deviation (SD), Kurtosis, Skewness and Lung volume (LV)]. LUS was used to quantify the B-lines detected in each patient by scanning a total of 13 intercostal spaces, on both anterior and posterior chest wall.Results:Among 59 SSc patients (81% women, mean age 48±14 years, 45% anti-Scl70 positive), 23 (39%) presented ILD on HRCT, of which 14 limited and 9 extensive. The mean visual semi-quantitative score was 6%, ranging from 0 to 66%. Our data showed a significantly different number of B-Lines in ILD vs non-ILD patients (median 38 vs 9, p <.005), a result which was further confirmed among non-ILD vs ILD> 20% (median 47 vs 9, p=.001) and ILD <20% (median 36 vs 9, p=.001) patients. Conversely, the number of B-lines was not statistically different between patients with ILD <20% and >20% (median 47 vs 36, p=.78). We observed a significant negative correlation between the number of B-lines and FVC (r=-.472, p<.05) TLC (r=-.436, p=.003), DLco (r=-.515, p<.001), DLCO/VA (r=.-306, p=.03). Finally, the number of B-lines showed a statistically significant correlation with the Goh score on 5 levels (r=.437, p=.001), MLA (r=.571, p<.001), kurtosis (r=-.285, p=.028), skewness (r=-.370, p = .004) and LV (r=-.277, p=.033). All data were confirmed analysing anterior and posterior B-Lines separately.Conclusion:Our study confirms that LUS represents a useful tool for the identification of SSc-ILD. In addition, we showed that LUS may be useful also for the quantification of the severity of SSc-ILD, by correlating with PFT parameters, radiomics parameters and visual radiological evaluation. Together with the PFTs, LUS could be used to increase the accuracy of the screening and, potentially, of the follow-up of SSc-ILD patients.Disclosure of Interests:Cosimo Bruni: None declared, Lavinia Mattolini: None declared, Lorenzo Tofani: None declared, Luna Gargani Consultant of: GE Healthcare, Philips Healthcare and Caption Health, Nicholas Landini: None declared, Gemma Lepri: None declared, Martina Orlandi: None declared, Serena Guiducci: None declared, Silvia Bellando Randone: None declared, Marco Matucci-Cerinic: None declared

scholarly journals Nailfold Videocapillaroscopy Is a Useful Tool to Recognize Definite Forms of Systemic Sclerosis and Idiopathic Inflammatory Myositis in Interstitial Lung Disease Patients

Diagnostics ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 253 ◽  
Author(s):  
Domenico Sambataro ◽  
Gianluca Sambataro ◽  
Alessandro Libra ◽  
Giovanna Vignigni ◽  
Fabio Pino ◽  
...  
Keyword(s):  
Systemic Sclerosis ◽  
Interstitial Lung Disease ◽  
Lung Disease ◽  
Correct Diagnosis ◽  
Diagnostic Assessment ◽  
Nailfold Videocapillaroscopy ◽  
High Resolution Computed Tomography ◽  
Inflammatory Myositis ◽  
Idiopathic Inflammatory Myositis ◽  
Diagnostic Role

Nailfold videocapillaroscopy (NVC) is an easy tool used for the assessment of patients with Raynaud’s phenomenon (RP) as possibly associated with systemic sclerosis (SSc). Recent insights have also highlighted its role in the diagnostic assessment of idiopathic inflammatory myopathies (IIMs). The aim of this study is to describe the diagnostic role of NVC in a series of 361 consecutive patients with interstitial lung disease (ILD). All the patients were assessed by clinical pulmonary and rheumatic examinations, blood exams, high-resolution computed tomography and NVC. NVC was considered positive only in the presence of avascular areas or giant capillaries, but also, the presence of bushy capillaries (BCs) was recorded. NVC was positive in 17.7% of ILD patients and in 78.1% of ILD patients associated with a diagnosis of connective tissue disease (CTD). In 25% of SSc-ILD patients, NVC proved necessary for a correct diagnosis. The presence of BCs and/or NVC positivity in ILD patients with normal levels of creatine phosphokinase is associated with amyopathic IIM, regardless the presence of RP. In conclusion, NVC is useful for the diagnostic assessment of incomplete forms of CTD and in amyopathic IIMs. NVC should be considered in the diagnostic assessment of ILD patients regardless of the presence of RP.

scholarly journals Applicability of radiomics in interstitial lung disease associated with systemic sclerosis: proof of concept

2020 ◽  
Author(s):  
K. Martini ◽  
B. Baessler ◽  
M. Bogowicz ◽  
C. Blüthgen ◽  
M. Mannil ◽  
...  
Keyword(s):  
Systemic Sclerosis ◽  
Interstitial Lung Disease ◽  
Pulmonary Function ◽  
Lung Disease ◽  
Data Augmentation ◽  
Visual Analysis ◽  
Area Under The Curve ◽  
Information Criterion ◽  
Visual Assessment ◽  
High Resolution Computed Tomography

Abstract Objective To retrospectively evaluate if texture-based radiomics features are able to detect interstitial lung disease (ILD) and to distinguish between the different disease stages in patients with systemic sclerosis (SSc) in comparison with mere visual analysis of high-resolution computed tomography (HRCT). Methods Sixty patients (46 females, median age 56 years) with SSc who underwent HRCT of the thorax were retrospectively analyzed. Visual analysis was performed by two radiologists for the presence of ILD features. Gender, age, and pulmonary function (GAP) stage was calculated from clinical data (gender, age, pulmonary function test). Data augmentation was performed and the balanced dataset was split into a training (70%) and a testing dataset (30%). For selecting variables that allow classification of the GAP stage, single and multiple logistic regression models were fitted and compared by using the Akaike information criterion (AIC). Diagnostic accuracy was evaluated from the area under the curve (AUC) from receiver operating characteristic (ROC) analyses, and diagnostic sensitivity and specificity were calculated. Results Values for some radiomics features were significantly lower (p < 0.05) and those of other radiomics features were significantly higher (p = 0.001) in patients with GAP2 compared with those in patients with GAP1. The combination of two specific radiomics features in a multivariable model resulted in the lowest AIC of 10.73 with an AUC of 0.96, 84% sensitivity, and 99% specificity. Visual assessment of fibrosis was inferior in predicting individual GAP stages (AUC 0.86; 83% sensitivity; 74% specificity). Conclusion The correlation of radiomics with GAP stage, but not with the visually defined features of ILD-HRCT, implies that radiomics might capture features indicating severity of SSc-ILD on HRCT, which are not recognized by visual analysis. Key Points • Radiomics features can predict GAP stage with a sensitivity of 84% and a specificity of almost 100%. • Extent of fibrosis on HRCT and a combined model of different visual HRCT-ILD features perform worse in predicting GAP stage. • The correlation of radiomics with GAP stage, but not with the visually defined features of ILD-HRCT, implies that radiomics might capture features on HRCT, which are not recognized by visual analysis.

scholarly journals THE PREVALENCE OF INTERSTITIAL LUNG DISEASE IN SYSTEMIC SCLEROSIS PATIENTS

2019 ◽  
pp. 1-3
Author(s):  
Julyan Al Fori
Keyword(s):  
Systemic Sclerosis ◽  
Interstitial Lung Disease ◽  
Lung Disease ◽  
High Resolution Computed Tomography ◽  
Atypical Chest Pain ◽  
Royal Hospital ◽  
Lung Capacity ◽  
Female Predominance ◽  
The Mean ◽  
Traction Bronchiectasis

OBJECTIVE: To report the prevalence of interstitial lung disease in Systemic Sclerosis patients at the Royal Hospital and compare our data with the literature. METHODS:All adult Omani patients with Systemic Sclerosis (SSc) who are under regular follow-up at the Royal Hospital were retrospectively enrolled from January 2006 to January 2014. RESULTS: A total of 49 cases of Systemic Sclerosis (SSc) patients were included. The mean age was 44.06 ± 11.9 years. There was a predominance of females (48 cases; 98%). Interstitial lung disease present in 30 cases (61%). The most frequent symptoms were dyspnea 47%, cough 33%, and others (e.g. atypical chest pain) 20%. There was no association with smoking, non-smoker (47 cases, 95.5%) versus ex. smoker (2 cases, 4%). The most high resolution computed tomography (HRCT) finding was traction bronchiectasis (21 cases, 42.9%) followed by honey comb appearance (19 cases, 38.8%). Pulmonary Function Test (PFT) was done in 33 cases. The mean total lung capacity (TLC) was 81. 06 ± 26.2. The mean diffusion lung capacity (DLCO) was 61.8± 28.3. Pulmonary hypertension was found in 10 cases only (20.4%) based on echocardiography. CONCLUSIONS: ILD was present in 30 cases out of 49 cases of SSc (61.2%) with female predominance. The most frequently observed HRCT change was traction bronchiectasis. Similarities and differences were found with respect to the previous reports from other countries

scholarly journals Increased levels of HE4 (WFDC2) in systemic sclerosis: a novel biomarker reflecting interstitial lung disease severity?

2020 ◽  
Vol 11 ◽  
pp. 204062232095642
Author(s):  
Mingxia Zhang ◽  
Liyun Zhang ◽  
Linning E ◽  
Ke Xu ◽  
Xu Fei Wang ◽  
...  
Keyword(s):  
Systemic Sclerosis ◽  
Interstitial Lung Disease ◽  
Lung Disease ◽  
Pulmonary Function Tests ◽  
Lavage Fluid ◽  
Ct Scans ◽  
Function Parameter ◽  
Enzyme Linked Immunosorbent Assay ◽  
Healthy Controls ◽  
High Resolution Computed Tomography

Background: Human epididymis protein 4 (HE4, also known as WFDC-2) has been implicated in fibrotic disorders pathobiology. We tested the hypothesis that HE4 may be used as a candidate biomarker for systemic sclerosis (SSc)-related interstitial lung disease (SSc-ILD). Methods: A total of 169 consecutive SSc patients and 169 age-and sex-matched healthy controls were enrolled and blood samples were collected. Pulmonary function tests (PFTs) and paired lavage was performed on 169 patients and 37 healthy controls. All patients were classified as having SSc-no ILD or SSc-ILD, based on high-resolution computed tomography (CT) scans of the chest, and a semiquantitative grade of ILD extent was evaluated through CT scans (grade 1, 0–25%; grade 2, 26–50%; grade 3, 51–75%; grade 4, 76–100%). Serum and bronchoalveolar lavage fluid (BALF) HE4 levels were measured by enzyme-linked immunosorbent assay. Results: Serum HE4 levels were higher in SSc patients [median (interquartile range), 139.4 (85.9–181.8) pmol/l] compared with healthy controls [39.5 (24.3–54.2) pmol/l, p < 0.001] and were higher in patients with SSc-ILD [172.1 (94.8–263.3) pmol/l] than in those with SSc-no ILD [97.4 (85.5–156.5) pmol/l, p < 0.001]. This observation was replicated in the BALF samples. Corresponding values were 510.8 (144.6–1013.8) pmol/l for SSc cohort, 754.4 (299–1060) pmol/l for SSc-ILD, 555.1 (203.7–776.2) pmol/l for SSc-no ILD, and 238.7 (97.7–397.6) pmol/l for controls. The semiquantitative grade of ILD on CT scan was significantly proportional to the HE4 levels and the lung function parameter (i.e., FVC) had a negative correlation with the HE4 levels. Conclusion: This is the first study to demonstrate the potential clinical utility of blood and BALF HE4 as a biomarker for SSc-ILD. Future prospective validation studies are warranted.

Effect of Bosentan on Systemic Sclerosis-associated Interstitial Lung Disease Ineligible for Cyclophosphamide Therapy: A Prospective Open-label Study

2011 ◽  
Vol 38 (10) ◽  
pp. 2186-2192 ◽  
Author(s):  
YOSHIAKI FURUYA ◽  
MASATAKA KUWANA
Keyword(s):  
Systemic Sclerosis ◽  
Interstitial Lung Disease ◽  
Pulmonary Function ◽  
Lung Disease ◽  
Pulmonary Function Tests ◽  
High Dose ◽  
Open Label ◽  
High Resolution Computed Tomography ◽  
Open Label Study ◽  
Label Study

Objective.To evaluate the clinical benefits of the endothelin receptor antagonist bosentan on interstitial lung disease (ILD) in patients with systemic sclerosis (SSc) who are ineligible for cyclophosphamide (CYC) therapy.Methods.In this prospective open-label study, 9 patients with SSc and ILD received bosentan for 24 months. The main reasons for avoiding CYC included severely impaired lung function, long disease duration, and relapse after CYC treatment. Pulmonary function tests and Doppler echocardiograms were evaluated every 6 months, and high-resolution computed tomography (HRCT) was performed every 12 months. For an extended survival analysis, 17 historical controls who met the inclusion criteria at referral and had not used any immunosuppressive or antifibrotic agents thereafter were selected from the SSc database.Results.Two patients did not finish the study; one developed vasculitis requiring high-dose corticosteroids and another died of bacterial pneumonia. The remaining 7 patients tolerated bosentan and completed the study period. There were trends toward mildly reduced forced vital capacity, total lung capacity, and diffusing capacity for carbon monoxide over time. Two patients developed pulmonary hypertension during the 24-month period. HRCT scores for ground-glass opacity, pulmonary fibrosis, and honeycomb cysts gradually increased. In the extended study, there was no difference in cumulative survival rate between the bosentan-treated and historical control groups.Conclusion.The gradual worsening of pulmonary function and HRCT findings in patients treated with bosentan was consistent with the natural course of SSc-associated ILD. This study does not support the use of bosentan for SSc-associated ILD even when CYC treatment is inadvisable.

scholarly journals Interstitial lung disease in systemic sclerosis

2016 ◽  
Vol 67 (4) ◽  
Author(s):  
E.A. Renzoni
Keyword(s):  
Systemic Sclerosis ◽  
Interstitial Lung Disease ◽  
Lung Disease ◽  
Lung Fibrosis ◽  
Immunosuppressive Agents ◽  
Significant Proportion ◽  
Clinical Markers ◽  
Significant Toxicity ◽  
Clinically Significant

Systemic sclerosis (SSc) is a connective tissue disease characterised by fibrosis of the skin and internal organs, autoimmune abnormalities and widespread vasculopathy. A degree of interstitial lung involvement is present in the majority of patients, although clinically significant lung fibrosis is present in approximately a third. Autoantibodies are significant clinical markers; anti-topoisomerase is tightly linked to lung fibrosis, whereas anti-centromere antibodies are protective. Further evaluation of markers of progression of lung fibrosis, such as markers of epithelial permeability, will be crucial in clinical management. The clinical course of SSc-associated interstitial lung disease is highly variable, with stability observed in a significant proportion of patients. Therefore, the decision of whether to treat is a challenging one, and should be based on evaluation of disease severity (on the basis of CT extent and lung function) and longitudinal disease behaviour. Two recently published placebo controlled randomized trials have shown a significant, if small, effect of cyclophosphamide on preventing FVC decline. However, because of the significant toxicity of cyclophosphamide, the assessment of alternative, less toxic, immunosuppressive agents for the long term management of SSc-associated interstitial lung disease is needed.

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