scholarly journals Role of sialidase Neu3 and ganglioside GM3 in cardiac fibroblasts activation

2020 ◽  
Vol 477 (17) ◽  
pp. 3401-3415
Author(s):  
Andrea Ghiroldi ◽  
Marco Piccoli ◽  
Pasquale Creo ◽  
Federica Cirillo ◽  
Paola Rota ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Transforming Growth Factor Beta ◽  
Cardiac Fibrosis ◽  
Transforming Growth Factor ◽  
Tissue Injury ◽  
Cardiac Fibroblasts ◽  
Primary Cultures ◽  
Cell Types ◽  
Cell Content ◽  
Ganglioside Gm3

Cardiac fibrosis is a key physiological response to cardiac tissue injury to protect the heart from wall rupture. However, its progression increases heart stiffness, eventually causing a decrease in heart contractility. Unfortunately, to date, no efficient antifibrotic therapies are available to the clinic. This is primarily due to the complexity of the process, which involves several cell types and signaling pathways. For instance, the transforming growth factor beta (TGF-β) signaling pathway has been recognized to be vital for myofibroblasts activation and fibrosis progression. In this context, complex sphingolipids, such as ganglioside GM3, have been shown to be directly involved in TGF-β receptor 1 (TGF-R1) activation. In this work, we report that an induced up-regulation of sialidase Neu3, a glycohydrolytic enzyme involved in ganglioside cell homeostasis, can significantly reduce cardiac fibrosis in primary cultures of human cardiac fibroblasts by inhibiting the TGF-β signaling pathway, ultimately decreasing collagen I deposition. These results support the notion that modulating ganglioside GM3 cell content could represent a novel therapeutic approach for cardiac fibrosis, warranting for further investigations.

scholarly journals MicroRNA-101a Inhibits Cardiac Fibrosis Induced by Hypoxia via Targeting TGFβRI on Cardiac Fibroblasts

2015 ◽  
Vol 35 (1) ◽  
pp. 213-226 ◽  
Author(s):  
Xin Zhao ◽  
Kejing Wang ◽  
Yuhua Liao ◽  
Qiutang Zeng ◽  
Yushu Li ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Transforming Growth Factor Beta ◽  
Cardiac Remodeling ◽  
Cardiac Fibrosis ◽  
Transforming Growth Factor ◽  
Cardiac Fibroblasts ◽  
Coronary Artery Occlusion ◽  
Artery Occlusion ◽  
Luciferase Reporter ◽  
Migration Ability

Background/Aims: Hypoxia is a basic pathological challenge that is associated with numerous cardiovascular disorders including aberrant cardiac remodeling. Transforming growth factor beta (TGF-β) signaling pathway plays a pivotal role in mediating cardiac fibroblast (CF) function and cardiac fibrosis. Recent data suggested that microRNA-101a (miR-101a) exerted anti-fibrotic effects in post-infarct cardiac remodeling and improved cardiac function. This study aimed to investigate the potential relationship between hypoxia, miR-101a and TGF-β signaling pathway in CFs. Methods and Results: Two weeks following coronary artery occlusion in rats, the expression levels of both TGFβ1 and TGFβRI were increased, but the expression of miR-101a was decreased at the site of the infarct and along its border. Cultured rat neonatal CFs treated with hypoxia were characterized by the up-regulation of TGFβ1 and TGFβRI and the down-regulation of miR-101a. Delivery of miR-101a mimics significantly suppressed the expression of TGFβRI and p-Smad 3, CF differentiation and collagen content of CFs. These anti-fibrotic effects were abrogated by co-transfection with AMO-miR-101a, an antisense inhibitor of miR-101a. The repression of TGFβRI, a target of miR-101a, was validated by luciferase reporter assays targeting the 3'UTR of TGFβRI. Additionally, we found that overexpression of miR-101a reversed the improved migration ability of CFs and further reduced CF proliferation caused by hypoxia. Conclusion: Our study illustrates that miR-101a exerts anti-fibrotic effects by targeting TGFβRI, suggesting that miR-101a plays a multi-faceted role in modulating TGF-β signaling pathway and cardiac fibrosis.

Abstract 782: Fra2 Mediates Oxygen-induced TGFbeta-1 mRNA Expression In Adult Cardiac Fibroblasts: Significance In Myocardial Fibrosis Following Ischemia-reperfusion Injury

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Sashwati Roy ◽  
Savita Khanna ◽  
Chandan K Sen
Keyword(s):  
Mrna Expression ◽  
Transforming Growth Factor Beta ◽  
Cardiac Fibrosis ◽  
Transforming Growth Factor ◽  
Ischemia Reperfusion Injury ◽  
Cardiac Fibroblasts ◽  
Ischemia Reperfusion ◽  
Luciferase Reporter ◽  
Mrna Levels

Background . Transforming growth factor beta-1 (TGFbeta-1) is a key cytokine implicated in the development of cardiac fibrosis following ischemia-reperfusion (IR) injury. The profibrotic effects of TGFbeta-1 are primarily attributable to the differentiation of cardiac fibroblasts (CF) to myofibroblasts. Previously, we have reported perceived hyperoxia (Circ Res 92:264 –71), sub-lethal reoxygenation shock during IR, induces differentiation of CF to myofibroblasts at the infarct site. The mechanisms underlying oxygen-sensitive induction of TGFbeta-1 mRNA remain to be characterized. Hypothesis . Fra2 mediates oxygen-induced TGFbeta-1 mRNA expression in adult cardiac fibroblasts. Methods. TGFbeta-1 mRNA expression in infarct tissue was investigated in an IR injury model. The left anterior descending coronary artery of mice was transiently occluded for 60 minutes followed by reperfusion to induce IR injury. Spatially resolved infarct and non-infarct tissues were collected at 0, 1, 3, 5, and 7 days post-IR using laser capture microdissection. TGFbeta-1 mRNA levels were measured using real-time PCR. To investigate the role of oxygen in the regulation of TGFbeta-1, we used our previously reported model of perceived hyperoxia where CF (from 5wks old mice) after isolation were cultured at 5%O 2 (physiological pO 2 ) followed by transferring them to 20%O 2 to induce hyperoxic insult. Results & Conclusions. In vivo, a significant increase (p<0.01; n=5) in TGFbeta-1 mRNA was observed at the infarct site already at day 1 post-IR. The levels continued to increase until day 7 post-IR. In vitro, exposure of CF to 20%O 2 hyperoxic insult induced TGFbeta-1 mRNA (p<0.001; n=4) and protein (p<0.01; n=4) expression. Using a TGFbeta-1 promoter-luciferase reporter and DNA binding assays, we collected first evidence that AP-1 and its component Fra2 as major mediators of oxygen-induced TGFbeta-1 expression. Exposure to 20%O 2 resulted in increased localization of Fra2 in nucleus. siRNA-dependent Fra-2 knock-down completely abrogated oxygen-induced TGFbeta1 expression. In conclusion, this study presents first evidence that Fra-2 is involved in inducible TGFbeta1 expression in CF. Fra2 was noted as being central in regulating oxygen-induced TGFbeta-1 expression.s

Abstract 425: Doxorubicin Upregulation of the Fibrotic Transforming Growth Factor-beta Pathway

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Trevi A Ramirez ◽  
Greg Aune
Keyword(s):  
Growth Factor ◽  
Signaling Pathway ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Cardiac Fibroblasts ◽  
Increased Risk ◽  
Pediatric Cancer Patients ◽  
Growth Factor Beta ◽  
Tgfb Signaling ◽  
Old Mice

Childhood cancer survivors are at an increased risk of heart disease as a result of their cancer treatments. Drugs like doxorubicin (DOX) are an effective part of treatment regimens, but have been proven to cause acute and chronic cardiotoxicity (DOX tox). An under-investigated aspect of DOX tox is the interstitial fibrosis that the majority of patients develop. This project aims to better understand the pathology of DOX-induced cardiac fibrosis and the role of the pro-fibrotic transforming growth factor-beta (TGFb) signaling pathway. Research in the area of fibrosis and the effect of DOX on cardiac fibroblasts will increase our understanding of DOX tox. This understanding will allow for improved treatment of pediatric cancer patients by reducing the cardiotoxic sequelae of many standard chemotherapy regimens. Cardiac fibroblasts, isolated from 3 week old mice and treated with 5 μM DOX, showed an increase in nuclear pSMAD compared to control cells via fluorescent immunocytology (2.06 ± 0.26 vs 1.13 ± 0.15, p<0.05). Mice treated with 3 mg/kg DOX injections from 2 weeks to 6 weeks of age showed increased TGFb staining in the left ventricle (1.83 ± 0.34 vs 0.87 ± 0.28, p<0.05) a week after treatment ceased. A subset of mice were followed into old age and sacrificed at 80 weeks. A clear increase in TGFb was seen with age. However, 80 week mice that were exposed to DOX early in life showed a greater increase in TGFb staining compared to untreated 80 week old mice (44.50 ± 2.48 vs 30.93 ± 2.30, p<0.001). Early DOX exposure causes chronic molecular changes as evidenced by acute and chronic changes in signaling molecules in cardiac tissue. Changes in collagen seen in earlier studies and increases in MMP-2 from the literature suggest a cardiac remodeling phenotype in DOX-exposed animals. This project demonstrates that DOX initiates changes to pro-fibrotic pathways, seemingly driven by the TGFb signaling pathway.

scholarly journals Cell type-specific control of human neuronectin secretion by polypeptide mediators and phorbol ester.

1989 ◽  
Vol 37 (12) ◽  
pp. 1777-1786 ◽  
Author(s):  
W J Rettig ◽  
P Garin-Chesa
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Malignant Tumors ◽  
Tissue Injury ◽  
Mesenchymal Cell ◽  
Cell Types ◽  
Skin Lesions ◽  
Psoriatic Skin ◽  
Tgf Beta

Neuronectin (NEC1) is a human extracellular matrix (ECM) protein expressed with a unique rostrocaudal pattern in white matter of the normal adult central nervous system. In addition, NEC1 is expressed in normal fetal and adult smooth muscle, along certain epithelial-mesenchymal junctions, and transiently in developing fetal cartilage. Region-specific induction of NEC1 is found in dermal wounds and in the reactive stroma of actinic keratoses, psoriatic skin lesions, and a range of malignant tumors. One explanation for these diverse tissue patterns is that cells capable of producing NEC1 are widely distributed in neural and mesenchymal tissues, but they become NEC1 producers only when induced by region-specific differentiation signals. In this study, we used cultured human cells to show that several regulatory polypeptides, including fibroblast growth factors, tumor necrosis factor, platelet-derived growth factor, nerve growth factor, and transforming growth factor-beta (TGF-beta), as well as 12-O-tetradecanoyl phorbol-13-acetate (TPA), modulate NEC1 secretion, with distinct patterns of inducing and inhibitory activities in different neural and mesenchymal cell types. TPA and TGF-beta act both as inducers and inhibitors of NEC1 secretion, depending on the target cell. These effects are specific for NEC1 and are not seen for several other secreted and membrane proteins studied. We suggest that NEC1 expression comes under different modes of extrinsic control in different cell lineages and in response to tissue injury and neoplasia.

scholarly journals Construction and Analysis of a ceRNA Network in Cardiac Fibroblast During Fibrosis Based on in vivo and in vitro Data

2021 ◽  
Vol 11 ◽  
Author(s):  
Qing-Yuan Gao ◽  
Hai-Feng Zhang ◽  
Zhi-Teng Chen ◽  
Yue-Wei Li ◽  
Shao-Hua Wang ◽  
...  
Keyword(s):  
Transforming Growth Factor Beta ◽  
Target Genes ◽  
Cardiac Fibrosis ◽  
Transforming Growth Factor ◽  
Cardiac Fibroblasts ◽  
Single Gene ◽  
Cardiac Fibroblast ◽  
Gene Set Enrichment Analysis ◽  
Differentially Expressed ◽  
Cerna Network

AimsActivation of cardiac fibroblasts (CF) is crucial to cardiac fibrosis. We constructed a cardiac fibroblast-related competing endogenous RNA (ceRNA) network. Potential functions related to fibrosis of “hub genes” in this ceRNA network were explored.Materials and MethodsThe Gene Expression Omnibus database was searched for eligible datasets. Differentially expressed messenger (m)RNA (DE-mRNA) and long non-coding (lnc)RNA (DE-lncRNA) were identified. microRNA was predicted and validated. A predicted ceRNA network was constructed and visualized by Cytoscape, and ceRNA crosstalk was validated. A Single Gene Set Enrichment Analysis (SGSEA) was done, and the Comparative Toxicogenomics Database (CTD) was employed to analyze the most closely associated pathways and diseases of DE-mRNA in the ceRNA network. The functions of DE-mRNA and DE-lncRNA in the ceRNA network were validated by small interfering (si)RNA depletion.ResultsThe GSE97358 and GSE116250 datasets (which described differentially expressed genes in human cardiac fibroblasts and failing ventricles, respectively) were used for analyses. Four-hundred-and-twenty DE-mRNA and 39 DE-lncRNA, and 369 DE-mRNA and 93 DE-lncRNA were identified, respectively, in the GSE97358 and GSE116250 datasets. Most of the genes were related to signal transduction, cytokine activity, and cell proliferation. Thirteen DE-mRNA with the same expression tendency were overlapped in the two datasets. Twenty-three candidate microRNAs were predicted and the expression of 11 were different. Only two DE-lncRNA were paired to any one of 11 microRNA. Finally, two mRNA [ADAM metallopeptidase domain 19, (ADAM19) and transforming growth factor beta induced, (TGFBI)], three microRNA (miR-9-5p, miR-124-3p, and miR-153-3p) and two lncRNA (LINC00511 and SNHG15) constituted our ceRNA network. siRNA against LINC00511 increased miR-124-3p and miR-9-5p expression, and decreased ADAM19 and TGFBI expression, whereas siRNA against SNHG15 increased miR-153-3p and decreased ADAM19 expression. ADAM19 and TGFBI were closely related to the TGF-β1 pathway and cardiac fibrosis, as shown by SGSEA and CTD, respectively. Depletion of two mRNA or two lncRNA could alleviate CF activation.ConclusionsThe CF-specific ceRNA network, including two lncRNA, three miRNA, and two mRNA, played a crucial role during cardiac fibrosis, which provided potential target genes in this field.

scholarly journals Tripartite Motif Protein 72 Regulates the Proliferation and Migration of Rat Cardiac Fibroblasts via the Transforming Growth Factor-β Signaling Pathway

Cardiology ◽  
2016 ◽  
Vol 134 (3) ◽  
pp. 340-346 ◽  
Author(s):  
Jianquan Zhao ◽  
Han Lei
Keyword(s):  
Growth Factor ◽  
Signaling Pathway ◽  
Cardiac Fibrosis ◽  
Transforming Growth Factor ◽  
Cardiac Fibroblasts ◽  
Neonatal Rat ◽  
Tripartite Motif ◽  
Tripartite Motif Protein ◽  
And Migration ◽  
Proliferation And Migration

Background: The proliferation and migration of cardiac fibroblasts are critical for the progress of cardiac fibrosis. Tripartite motif protein 72 (Trim72), also known as MG53, mediates the dynamic process of membrane fusion and exocytosis in striated muscle. However, the role of Trim72 in the proliferation and migration of cardiac fibroblasts is unknown. Methods: In the present study, we used small interference RNA (siRNA) to silence Trim72 and then investigated the effects of Trim72 on cardiac fibroblast proliferation and migration, which were activated during cardiac remodeling after myocardial infarction. Cardiac fibroblasts were isolated from 2- to 3-day-old neonatal Sprague-Dawley rats and transfected with siRNA. A cell-counting assay was used to determine the proliferation of cardiac fibroblasts. A Boyden chamber assay was performed to determine the migration of cardiac fibroblasts. Results: Our study has, for the first time, demonstrated that Trim72 regulates the cell proliferation and migration of rat cardiac fibroblasts. Furthermore, the data from the gene expression profile microarray analysis indicate that Trim72 depletion can cause downregulation of the transforming growth factor (TGF)-β signaling pathway, suggesting that Trim72 regulates the proliferation and migration of cardiac fibroblasts probably via the TGF-β signaling pathway. Conclusions: We have demonstrated that Trim72 might play a pivotal role in the proliferation of neonatal rat cardiac fibroblasts, which could be a potential target for the treatment of cardiac fibrosis. However, the involvement of other signaling pathways and factors in the formation of cardiac fibrosis cannot be excluded.

scholarly journals miR-301a-5p Regulates TGFB2 during Chicken Spermatogenesis

Genes ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1695
Author(s):  
Qixin Guo ◽  
Yong Jiang ◽  
Hao Bai ◽  
Guohong Chen ◽  
Guobin Chang
Keyword(s):  
Growth Factor ◽  
Signaling Pathway ◽  
Transforming Growth Factor Beta ◽  
Target Genes ◽  
Transforming Growth Factor ◽  
Expression Profiles ◽  
Cell Types ◽  
Germline Cell ◽  
Micro Rnas ◽  
Growth Factor Beta

The process of spermatogenesis is complex and systemic, requiring the cooperation of many regulators. However, little is known about how micro RNAs (miRNAs) regulate spermatogenesis in poultry. In this study, we investigated key miRNAs and their target genes that are involved in spermatogenesis in chickens. Next-generation sequencing was conducted to determine miRNA expression profiles in five cell types: primordial germ cells (PGCs), spermatogonial stem cells (SSCs), spermatogonia (Spa), and chicken sperm. Next, we analyzed and identified several key miRNAs that regulate spermatogenesis in the four germline cell miRNA profiles. Among the enriched miRNAs, miRNA-301a-5p was the key miRNA in PGCs, SSCs, and Spa. Through reverse transcription quantitative PCR (RT-qPCR), dual-luciferase, and miRNA salience, we confirmed that miR-301a-5p binds to transforming growth factor-beta 2 (TGFβ2) and is involved in the transforming growth factor-beta (TGF-β) signaling pathway and germ cell development. To the best of our knowledge, this is the first demonstration of miR-301a-5p involvement in spermatogenesis by direct binding to TGFβ2, a key gene in the TGF-β signaling pathway. This finding contributes to the insights into the molecular mechanism through which miRNAs regulate germline cell differentiation and spermatogenesis in chickens.

scholarly journals The ER Unfolded Protein Response Effector, ATF6, Reduces Cardiac Fibrosis and Decreases Activation of Cardiac Fibroblasts

2020 ◽  
Vol 21 (4) ◽  
pp. 1373
Author(s):  
Winston T. Stauffer ◽  
Erik A. Blackwood ◽  
Khalid Azizi ◽  
Randal J. Kaufman ◽  
Christopher C. Glembotski
Keyword(s):  
Cardiac Fibrosis ◽  
Transforming Growth Factor ◽  
Cardiac Fibroblasts ◽  
Smooth Muscle Actin ◽  
Transforming Growth Factor Β ◽  
Cell Types ◽  
Unfolded Protein ◽  
Disease States ◽  
Activating Transcription Factor ◽  
Protein Response

Activating transcription factor-6 α (ATF6) is one of the three main sensors and effectors of the endoplasmic reticulum (ER) stress response and, as such, it is critical for protecting the heart and other tissues from a variety of environmental insults and disease states. In the heart, ATF6 has been shown to protect cardiac myocytes. However, its roles in other cell types in the heart are unknown. Here we show that ATF6 decreases the activation of cardiac fibroblasts in response to the cytokine, transforming growth factor β (TGFβ), which can induce fibroblast trans-differentiation into a myofibroblast phenotype through signaling via the TGFβ–Smad pathway. ATF6 activation suppressed fibroblast contraction and the induction of α smooth muscle actin (αSMA). Conversely, fibroblasts were hyperactivated when ATF6 was silenced or deleted. ATF6 thus represents a novel inhibitor of the TGFβ–Smad axis of cardiac fibroblast activation.

DYNAMIC BIOREACTOR MODEL TO MIMIC EARLY CARDIAC FIBROSIS IN DIABETES

2021 ◽  
pp. 2150047
Author(s):  
SPENCER MARSH ◽  
MADELINE RAUDAT ◽  
BETHANY LEFEBER ◽  
LAURA BETH HERNDON ◽  
HOWARD HERBERT ◽  
...  
Keyword(s):  
High Glucose ◽  
Cardiac Fibrosis ◽  
Transforming Growth Factor ◽  
Tissue Injury ◽  
Cardiac Fibroblasts ◽  
Cardiac Fibroblast ◽  
Mechanical Stimuli ◽  
Adequate Model ◽  
Fibroblast Activation ◽  
Glucose Levels

In clinical diabetic cardiomyopathy, hyperglycemia and dyslipidemia induce tissue injury, activation of cardiac fibroblasts and interstitial and perivascular fibrosis. Myofibroblasts repair the injured tissue by increasing collagen deposition in the cardiac interstitium and suppressing the activity of matrix metalloproteinases. The goal of this study was to find an ideal model to mimic the effect of high glucose concentration on human cardiac fibroblast activation. The profibrotic role of the transforming growth factor-[Formula: see text] (TGF-[Formula: see text]) and the protective modulation of nitric oxide were examined in two-dimensional and three-dimensional cell culture models, as well as tissue engineering models, that involved the use of cardiac fibroblasts cultured within myocardial matrix scaffolds mounted in a bioreactor that delivered biochemical and mechanical stimuli. Results showed that high glucose levels were potent pro-fibrotic stimuli. In addition, high glucose levels in concert with TGF-[Formula: see text] constituted very strong signals that induced human cardiac fibroblast activation. Cardiac fibroblasts cultured within decellularized myocardial scaffolds and exposed to biochemical and mechanical stimuli represented an adequate model for this pathology. In conclusion, the bioreactor platform was instrumental in establishing an in vitro model of early fibrosis; this platform could be used to test the effects of various agents targeted to mitigate the fibrotic processes.

scholarly journals The AP-1 Transcription Factor Fosl-2 Regulates Autophagy in Cardiac Fibroblasts during Myocardial Fibrogenesis

2021 ◽  
Vol 22 (4) ◽  
pp. 1861
Author(s):  
Jemima Seidenberg ◽  
Mara Stellato ◽  
Amela Hukara ◽  
Burkhard Ludewig ◽  
Karin Klingel ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Molecular Mechanisms ◽  
Cardiac Fibrosis ◽  
Type I Collagen ◽  
Transforming Growth Factor ◽  
Cardiac Fibroblasts ◽  
Smooth Muscle Actin ◽  
Beclin 1 ◽  
Type I ◽  
Alpha Smooth Muscle Actin

Background: Pathological activation of cardiac fibroblasts is a key step in development and progression of cardiac fibrosis and heart failure. This process has been associated with enhanced autophagocytosis, but molecular mechanisms remain largely unknown. Methods and Results: Immunohistochemical analysis of endomyocardial biopsies showed increased activation of autophagy in fibrotic hearts of patients with inflammatory cardiomyopathy. In vitro experiments using mouse and human cardiac fibroblasts confirmed that blockade of autophagy with Bafilomycin A1 inhibited fibroblast-to-myofibroblast transition induced by transforming growth factor (TGF)-β. Next, we observed that cardiac fibroblasts obtained from mice overexpressing transcription factor Fos-related antigen 2 (Fosl-2tg) expressed elevated protein levels of autophagy markers: the lipid modified form of microtubule-associated protein 1A/1B-light chain 3B (LC3BII), Beclin-1 and autophagy related 5 (Atg5). In complementary experiments, silencing of Fosl-2 with antisense GapmeR oligonucleotides suppressed production of type I collagen, myofibroblast marker alpha smooth muscle actin and autophagy marker Beclin-1 in cardiac fibroblasts. On the other hand, silencing of either LC3B or Beclin-1 reduced Fosl-2 levels in TGF-β-activated, but not in unstimulated cells. Using a cardiac hypertrophy model induced by continuous infusion of angiotensin II with osmotic minipumps, we confirmed that mice lacking either Fosl-2 (Ccl19CreFosl2flox/flox) or Atg5 (Ccl19CreAtg5flox/flox) in stromal cells were protected from cardiac fibrosis. Conclusion: Our findings demonstrate that Fosl-2 regulates autophagocytosis and the TGF-β-Fosl-2-autophagy axis controls differentiation of cardiac fibroblasts. These data provide a new insight for the development of pharmaceutical targets in cardiac fibrosis.

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