scholarly journals MiR-27b-3p inhibits the progression of renal fibrosis via suppressing STAT1

Human Cell ◽  
2021 ◽  
Vol 34 (2) ◽  
pp. 383-393
Author(s):  
Lin Bai ◽  
Yongtao Lin ◽  
Juan Xie ◽  
Yiyuan Zhang ◽  
Hongwu Wang ◽  
...  
Keyword(s):  
Renal Fibrosis ◽  
Transforming Growth Factor ◽  
Luciferase Assay ◽  
Mesenchymal Transition ◽  
Collagen Iii ◽  
Tgf Β1 ◽  
Active Caspase

AbstractRenal fibrosis is a pathologic change in chronic kidney disease (CKD). MicroRNAs (miRNAs) have been shown to play an important role in the development of renal fibrosis. However, the biological role of miR-27b-3p in renal fibrosis remains unclear. Thus, this study aimed to investigate the role of miR-27b-3p in the progression of renal fibrosis. In this study, HK-2 cells were stimulated with transforming growth factor (TGF)-β1 for mimicking fibrosis progression in vitro. The unilateral ureteric obstruction (UUO)-induced mice renal fibrosis in vivo was established as well. The results indicated that the overexpression of miR-27b-3p significantly inhibited epithelial-to-mesenchymal transition (EMT) in TGF-β1-stimulated HK-2 cells, as shown by the decreased expressions of α-SMA, collagen III, Fibronectin and Vimentin. In addition, overexpression of miR-27b-3p markedly decreased TGF-β1-induced apoptosis in HK-2 cells, as evidenced by the decreased levels of Fas, active caspase 8 and active caspase 3. Meanwhile, dual-luciferase assay showed that miR-27b-3p downregulated signal transducers and activators of transcription 1 (STAT1) expression through direct binding with the 3′-UTR of STAT1. Furthermore, overexpression of miR-27b-3p attenuated UUO-induced renal fibrosis via downregulation of STAT1, α-SMA and collagen III. In conclusion, miR-27b-3p overexpression could alleviate renal fibrosis via suppressing STAT1 in vivo and in vitro. Therefore, miR-27b-3p might be a promising therapeutic target for the treatment of renal fibrosis.

scholarly journals Identification of a microRNA signature in renal fibrosis: role of miR-21

2011 ◽  
Vol 301 (4) ◽  
pp. F793-F801 ◽  
Author(s):  
Abolfazl Zarjou ◽  
Shanzhong Yang ◽  
Edward Abraham ◽  
Anupam Agarwal ◽  
Gang Liu
Keyword(s):  
Epithelial Cells ◽  
Renal Fibrosis ◽  
Transforming Growth Factor ◽  
Response To Treatment ◽  
Tubular Epithelial Cells ◽  
Altered Expression ◽  
Tnf Α ◽  
Tgf Β1

Renal fibrosis is a final stage of many forms of kidney disease and leads to impairment of kidney function. The molecular pathogenesis of renal fibrosis is currently not well-understood. microRNAs (miRNAs) are important players in initiation and progression of many pathologic processes including diabetes, cancer, and cardiovascular disease. However, the role of miRNAs in kidney injury and repair is not well-characterized. In the present study, we found a unique miRNA signature associated with unilateral ureteral obstruction (UUO)-induced renal fibrosis. We found altered expression in UUO kidneys of miRNAs that have been shown to be responsive to stimulation by transforming growth factor (TGF)-β1 or TNF-α. Among these miRNAs, miR-21 demonstrated the greatest increase in UUO kidneys. The enhanced expression of miR-21 was located mainly in distal tubular epithelial cells. miR-21 expression was upregulated in response to treatment with TGF-β1 or TNF-α in human renal tubular epithelial cells in vitro. Furthermore, we found that blocking miR-21 in vivo attenuated UUO-induced renal fibrosis, presumably through diminishing the expression of profibrotic proteins and reducing infiltration of inflammatory macrophages in UUO kidneys. Our data suggest that targeting specific miRNAs could be a novel therapeutic approach to treat renal fibrosis.

scholarly journals HMGA2-induced epithelial–mesenchymal transition is reversed by let-7d in intrauterine adhesions

2020 ◽  
Author(s):  
Minmin Song ◽  
Chenrui Cao ◽  
Zhenhua Zhou ◽  
Simin Yao ◽  
Peipei Jiang ◽  
...  
Keyword(s):  
Transforming Growth Factor ◽  
Epithelial Mesenchymal Transition ◽  
High Mobility ◽  
Transforming Growth Factor Β ◽  
In Vitro Models ◽  
Luciferase Assay ◽  
Intrauterine Adhesions ◽  
Mesenchymal Transition

Abstract Intrauterine adhesions (IUAs), the leading cause of uterine infertility, are characterized by endometrial fibrosis. The management of IUA is challenging because the pathogenesis of the disease largely unknown. In this study, we demonstrate that the mRNA and protein levels of high mobility group AT-hook 2 (HMGA2) were increased by nearly 3-fold (P < 0.0001) and 5-fold (P = 0.0095) in the endometrial epithelial cells (EECs) of IUA patients (n = 18) compared to controls. In vivo and in vitro models of endometrial fibrosis also confirmed the overexpression of HMGA2 in EECs. In vitro cell experiments indicated that overexpression of HMGA2 promoted the epithelial–mesenchymal transition (EMT) while knockdown of HMGA2 reversed transforming growth factor-β-induced EMT. A dual luciferase assay confirmed let-7d microRNA downregulated HMGA2 and repressed the pro-EMT effect of HMGA2 in vitro and in vivo. Therefore, our data reveal that HMGA2 promotes IUA formation and suggest that let-7d can depress HMGA2 and may be a clinical targeting strategy in IUA.

scholarly journals Blockade of Autophagy Prevents the Development and Progression of Peritoneal Fibrosis

2021 ◽  
Vol 12 ◽  
Author(s):  
Yingfeng Shi ◽  
Yan Hu ◽  
Yi Wang ◽  
Xiaoyan Ma ◽  
Lunxian Tang ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Peritoneal Fibrosis ◽  
Mesenchymal Transition ◽  
Rat Models ◽  
Ultrafiltration Failure ◽  
Tgf Β1

Peritoneal fibrosis (PF) is a major cause of ultrafiltration failure in long-term peritoneal dialysis (PD) patients. Nevertheless, limited measures have been shown to be effective for the prevention and treatment of PF. Some views reveal that activation of autophagy ameliorates PF but others demonstrate that autophagy promotes PF. It is obvious that the role of autophagy in PF is controversial and further studies are needed. Here, we investigated the role of autophagy in rat models of PF and damaged cultured human peritoneal mesothelial cells (HPMCs). Autophagy was highly activated in fibrotic peritoneum from two PF rat models induced by 4.25% peritoneal dialysate fluid (PDF) and 0.1% chlorhexidine gluconate (CG). Blockade of autophagy with 3-MA effectively prevented PF in both models and reversed epithelial to mesenchymal transition (EMT) by down-regulating TGF-β/Smad3 signaling pathway and downstream nuclear transcription factors Slug and Snail. Treatment with 3-MA also inhibited activation of EGFR/ERK1/2 signaling pathway during PF. Moreover, 3-MA prominently decreased STAT3/NF-κB-mediated inflammatory response and macrophage infiltration, and prevented peritoneal angiogenesis through downregulation of β-catenin signal. In addition, TGF-β1 stimulation up-regulated autophagic activity as evidenced by the increased autophagosome in vitro. Exposure of HPMCs to TGF-β1 resulted in the induction of EMT and activation of TGF-β/Smad3, EGFR/ERK1/2 signaling pathways. Treatment with 3-MA blocked all these responses. In addition, delayed administration of 3-MA was effective in reducing EMT induced by TGF-β1. Taken together, our study indicated that autophagy might promote PF and 3-MA had anti-fibrosis effect in vivo and in vitro. These results suggest that autophagy could be a potential target on PF therapy for clinical patients with long-term PD.

Lysine-specific demethylase 1 induced epithelial–mesenchymal transition and promoted renal fibrosis through Jagged-1/Notch signaling pathway

2021 ◽  
pp. 096032712110387
Author(s):  
Huali Zhang ◽  
Jiaming Xing ◽  
Lingwei Zhao
Keyword(s):  
Cell Invasion ◽  
Renal Fibrosis ◽  
Epithelial Mesenchymal Transition ◽  
Notch 1 ◽  
Mesenchymal Transition ◽  
Lysine Specific Demethylase ◽  
Tgf Β1 ◽  
E Cadherin

Objective TGF-β1-induced excessive deposition of extracellular matrix (ECM) and epithelial-mesenchymal transition (EMT) process of tubular epithelial cells play critical roles in the progression of renal fibrosis. We are aimed to explore the effects of lysine-specific demethylase 1 (LSD1) in TGF-β1-treated HK-2 cells and in rats with unilateral ureteral obstruction (UUO), and to investigate the underlying molecular mechanism. Methods TGF-β1-treated HK-2 cells and UUO-treated rats were used to establish the model of renal fibrosis in vitro and in vivo, respectively. Protein expression of LSD1, E-cadherin, a-smooth muscle actin (a-SMA), Vimentin, Jagged-1, Notch-1 and Notch-2 were detected by Western blot. The concentrations of type I collagen (Col-I) and Fibronectin (FN) were measured by ELISA. Transwell assay were used to assess cell invasion. Results LSD1 was dramatically increased in TGF-β1-stimulated HK-2 cells. Knockdown of LSD1 decreased the TGF-β1-induced secretion of Col-I and FN, and suppressed TGF-β1-induced expression of E-cadherin,α-SMA and Vimentin, while suppressed cell invasion. Consistent with the in vitro data, the severe histopathological damage, collagen deposition and reduced E-cadherin, increased α-SMA induced by UUO was abated by the knockdown of LSD1 in vivo. Moreover, knockdown of LSD1 suppressed TGF-β1-induced expression of Jagged-1, Notch-1 and Notch-2. Furthermore, we found that inhibition of Notch signaling by a γ-secretase inhibitor RO4929097 almost recapitulated the effects of LSD1 knockdown in TGF-β1-induced HK-2 cells, and at least in part reversed the effects of LSD1 overexpression on EMT and ECM deposition in HK-2 cells. Conclusions Taken together, LSD1 significantly impact on the progression of TGF-β1-mediated EMT and ECM deposition in HK-2 cells, and it may represent novel target for the prevention strategies of renal fibrosis.

Silencing of the lncRNA TUG1 attenuates the epithelial-mesenchymal transition of renal tubular epithelial cells by sponging miR-141-3p via regulating β-catenin

2020 ◽  
Vol 319 (6) ◽  
pp. F1125-F1134
Author(s):  
Bo Zhang ◽  
Chengguang Zhao ◽  
Ling Hou ◽  
Yubin Wu
Keyword(s):  
Transforming Growth Factor ◽  
Epithelial Mesenchymal Transition ◽  
Interstitial Fibrosis ◽  
Morphological Changes ◽  
In Vivo Model ◽  
Mesenchymal Transition ◽  
Matrix Deposition ◽  
Tgf Β1

Renal interstitial fibrosis (RIF) is characterized by excessive extracellular matrix deposition and involves epithelial-mesenchymal transition (EMT). The lncRNA taurine-upregulated gene 1 ( TUG1) participates in EMT in several cancers; however, the effect and underlying mechanism of TUG1 in RIF-related EMT remain unclear. Here, we explored the mechanisms by which TUG1 modulates RIF. An in vivo model of renal fibrosis was established by unilateral ureteral obstruction in Balb/c mice. Human renal proximal tubular epithelial (HK-2) cells treated with transforming growth factor (TGF)-β1 were used to induce the in vitro model. Morphological changes and TUG1 expression were assessed. HK-2 cells were transfected with siRNA to silence TUG1. Western blot analysis, immunofluorescence staining, cell proliferation, and migration assays were performed to examine TGF-β1-induced changes in EMT markers and EMT-like cell behaviors. TUG1 and β-catenin ( CTNNB1) levels were significantly upregulated, whereas miR-141-3p was significantly downregulated, during EMT in vitro and in vivo. TUG1 knockdown or miR-141-3p overexpression supported the epithelioid morphology of HK-2 cells while enhancing the downregulation of E-cadherin and upregulation of vimentin, α-smooth muscle actin, and β-catenin levels in TGF-β1-treated HK-2 cells. TUG1 knockdown promoted the proliferation and decreased the migration of HK-2 cells and enhanced the downregulation of miR-141-3p levels in TGF-β1-treated HK-2 cells. TUG1 directly targeted miR-141-3p, and miR-141-3p was directly bound to CTNNB1. Downregulation of miR-141-3p inhibited TUG1 silencing-induced suppression of EMT. In conclusion, TUG1 promotes EMT in TGF-β1-induced HK-2 cells via upregulation of β-catenin levels by sponging miR-141-3p, suggesting a novel therapeutic candidate for RIF.

P0972INHIBITION OF LYSINE63 UBIQUITINATION PREVENTS THE PROGRESSION OF RENAL FIBROSIS IN DIABETIC NEPHROPATHY IN VITRO AND IN VIVO

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Francesca Conserva ◽  
Paola Pontrelli ◽  
Rossella Menghini ◽  
Michele Rossini ◽  
Alessandra Stasi ◽  
...  
Keyword(s):  
Diabetic Nephropathy ◽  
Drug Combination ◽  
Renal Fibrosis ◽  
Renal Damage ◽  
Mesenchymal Transition ◽  
Ubiquitinated Proteins ◽  
Collagen Iii ◽  
Sirius Red

Abstract Background and Aims Diabetic Nephropathy (DN) is the primary cause of end stage renal disease (ESRD). Our group demonstrated that in DN an accumulation of lysine63 (K63)-ubiquitinated proteins at tubular level is involved in the progression of renal damage, in particular renal fibrosis. Current treatments do not provide complete renoprotection and targeted therapies that prevent fibrosis or delay its progression are still lacking. Aim of the present study was to evaluate the renoprotective effect of specific drug and their combinations, including an inhibitor of K63 ubiquitination (K63Ub) and/or an anti-hypertensive agent, in vitro and in vivo in a murine model of DN. Method Renal Proximal Tubule Epithelial Cells (HK2) were pre-incubated with a specific inhibitor of K63Ub and/or with the ACE-inhibitor Ramipril. Accumulation of K63 ubiquitinated proteins along with α-sma expression, indicator of epithelial-to-mesenchymal transition (EMT), were analyzed through immunofluorescence and western blotting. The same drug combination was also tested in streptozotocin (STZ)-treated DBA/2J mice, a model of human DN. In mice, K63Ub was evaluated by IHC, while renal fibrosis was evaluated by Sirius red and Collagen III expression. Urinary albuminuria was measured by ELISA. Results We observed that the association of the specific K63Ub inhibitor with Ramipril was able to block hyperglycemia-induced EMT in HK2 cells by significantly reducing α-sma expression, when compared to single drugs alone (p<0.05).To demonstrate the efficacy of these drug combinations in reducing the progression of renal damage in DN we firstly confirmed the increased accumulation of K63 Ub proteins in DBA/2J STZ-treated mice (p=0.01). Interestingly, increased K63Ub in diabetic mice was also associated to increased tubular-interstitial fibrosis (p<0.05). Treatment of STZ-mice with the specific K63Ub inhibitor was able to reduce both K63Ub proteins accumulation and renal fibrosis, evaluated on kidney samples by IHC against Collagen III (p≤0.05) and by Sirius Red staining (p≤0.05) when compared to both untreated mice and mice treated with ramipril. Importantly, treatment with the K63Ub inhibitor alone did not reduce albuminuria (STZ-mice: 561.29±390.56; STZ+K63Ubinhibitor: 724.25±690.89; p=n.s.), while the drug combination including the specific K63Ub inhibitor and Ramipril, significantly reduced both K63Ub-related fibrosis and albuminuria (p=0.01), demonstrating an addictive and synergic effect of these molecules when used in combination. Conclusion Our data demonstrated and confirmed the importance of K63Ub in the progression of renal fibrosis in vitro and in vivo. We proposed and patented a novel combination of drugs that ameliorates both fibrosis and proteinuria in DN. Novel treatment regimens could represent an important goal for reducing the incidence of ESRD related to diabetes complication.

scholarly journals Oligo-Fucoidan Improves Diabetes-Induced Renal Fibrosis via Activation of Sirt-1, GLP-1R, and Nrf2/HO-1: An In Vitro and In Vivo Study

Nutrients ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 3068 ◽  
Author(s):  
Wen-Chun Yu ◽  
Ren-Yeong Huang ◽  
Tz-Chong Chou
Keyword(s):  
Renal Fibrosis ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
High Mobility ◽  
Renal Diseases ◽  
Heme Oxygenase 1 ◽  
Diabetic Mice ◽  
Tgf Β1

Fucoidan extracted from brown algae has multiple beneficial functions. In this study, we investigated the effects of low-molecular-weight fucoidan (oligo-FO) on renal fibrosis under in vitro and in vivo diabetic conditions, and its molecular mechanisms. Advanced glycation product (AGE)-stimulated rat renal proximal tubular epithelial cells (NRK-52E) and diabetic mice induced by high-fat diet and intraperitoneal injection of streptozotocin and nicotinamide were used. Oligo-FO treatment significantly inhibited anti-high mobility group box 1 (HMGB1)/RAGE/ anti-nuclear factor-kappa B (NF-κB)/transforming growth factor-β1 (TGF-β1)/TGF-β1R/Smad 2/3/fibronectin signaling pathway and HIF-1α activation in AGE-stimulated NRK-52E cells. Conversely, the expression and activity of Sirt-1; the levels of ubiquitin-specific peptidase 22 (USP22), p-AMPK, glucagon-like peptide-1 receptor (GLP-1R), and heme oxygenase-1 (HO-1); and Nrf2 activation were remarkably increased by oligo-FO in AGE-stimulated cells. However, the above effects of oligo-FO were greatly diminished by inhibiting Sirt-1, HO-1, or GLP-1R activity. Similar changes of these pro-fibrotic genes in the kidney and a marked attenuation of renal injury and dysfunction were observed in oligo-FO-treated diabetic mice. These findings indicated that the inhibitory effects of the oligo-FO on diabetes-evoked renal fibrosis are mediated by suppressing TGF-β1-activated pro-fibrogenic processes via Sirt-1, HO-1, and GLP-1R dependence. Collectively, fucoidan-containing foods or supplements may be potential agents for ameliorating renal diseases due to excessive fibrosis.

scholarly journals Ameliorative role of SIRT1 in peritoneal fibrosis: an in vivo and in vitro study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yanhong Guo ◽  
Liuwei Wang ◽  
Rong Gou ◽  
Yulin Wang ◽  
Xiujie Shi ◽  
...  
Keyword(s):  
Transforming Growth Factor ◽  
In Vitro Study ◽  
Transforming Growth Factor Β ◽  
Peritoneal Fibrosis ◽  
Mesenchymal Transition ◽  
Protein Levels ◽  
And Function

Abstract Background Peritoneal fibrosis is one of the major complications induced by peritoneal dialysis (PD). Damaged integrity and function of peritoneum caused by peritoneal fibrosis not only limits the curative efficacy of PD and but affects the prognosis of patients. However, the detailed mechanisms underlying the process remain unclear and therapeutic strategy targeting TGF‐β is deficient. Transforming growth factor‐β (TGF‐β) signaling participates in the progression of peritoneal fibrosis through enhancing mesothelial-mesenchymal transition of mesothelial cells. Methods The study aims to demonstrate the regulatory role of Sirtuin1 (SIRT1) to the TGF‐β signaling mediated peritoneal fibrosis. SIRT1−/− mice were used to establish animal model. Masson’s staining and peritoneal equilibration assay were performed to evaluate the degree of peritoneal fibrosis. QRT-PCR assays were used to estimate the RNA levels of Sirt1 and matrix genes related to peritoneal fibrosis, and their protein levels were examined by Western blot assays. Results SIRT1 significantly decreased in vivo post PD treatment. SIRT1 knockout exacerbated peritoneal fibrosis both in vivo and vitro. Overexpression of SIRT1 efficiently inhibited peritoneal fibrosis by inhibiting the peritoneal inflammation and the activation of TGF‐β signaling. Conclusion SIRT1 ameliorated peritoneal fibrosis both in vivo and in vitro through inhibiting the expression of protein matrix induced by TGF‐β signaling.

scholarly journals Epithelial and interstitial Notch1 activity contributes to the myofibroblastic phenotype and fibrosis

2019 ◽  
Vol 17 (1) ◽  
Author(s):  
Weilong Hong ◽  
Ge Zhang ◽  
Hong Lu ◽  
Yangyang Guo ◽  
Shizhang Zheng ◽  
...  
Keyword(s):  
Epithelial Mesenchymal Transition ◽  
Cultured Fibroblasts ◽  
Mesenchymal Transition ◽  
Matrix Deposition ◽  
Specific Antagonist ◽  
Related Pathway ◽  
Tgf Β1

Abstract Background Notch1 signalling is a stem-cell-related pathway that is essential for embryonic development, tissue regeneration and organogenesis. However, the role of Notch1 in the formation of myofibroblasts and fibrosis in kidneys following injury remains unknown. Methods The activity of Notch1 signalling was evaluated in fibrotic kidneys in CKD patients and in ureteral obstructive models in vivo and in cultured fibroblasts and TECs in vitro. In addition, the crosstalk of Notch1 with TGF-β1/Smad2/3 signalling was also investigated. Results Notch1 activity was elevated in fibrotic kidneys of rat models and patients with chronic kidney disease (CKD). Further study revealed that epithelial and interstitial Notch1 activity correlated with an α-SMA-positive myofibroblastic phenotype. In vitro, injury stimulated epithelial Notch1 activation and epithelial-mesenchymal transition (EMT), resulting in matrix deposition in tubular epithelial cells (TECs). Additionally, interstitial Notch1 activation in association with fibroblast-myofibroblast differentiation (FMD) in fibroblasts mediated a myofibroblastic phenotype. These TGF-β1/Smad2/3-dependent phenotypic transitions were abolished by Notch1 knockdown or a specific antagonist, DAPT, and were exacerbated by Notch1 overexpression or an activator Jagged-1-Fc chimaera protein. Interestingly, as a major driving force behind the EMT and FMD, TGF-β1, also induced epithelial and interstitial Notch1 activity, indicating that TGF-β1 may engage in crosstalk with Notch1 signalling to trigger fibrogenesis. Conclusion These findings suggest that epithelial and interstitial Notch1 activation in kidneys following injury contributes to the myofibroblastic phenotype and fibrosis through the EMT in TECs and to the FMD in fibroblasts by targeting downstream TGF-β1/Smad2/3 signalling.

Transforming growth factor-β1 increases airway wound repair via MMP-2 upregulation: a new pathway for epithelial wound repair?

2006 ◽  
Vol 290 (6) ◽  
pp. L1277-L1282 ◽  
Author(s):  
E. Lechapt-Zalcman ◽  
V. Prulière-Escabasse ◽  
D. Advenier ◽  
S. Galiacy ◽  
C. Charrière-Bertrand ◽  
...  
Keyword(s):  
Growth Factor ◽  
Epithelial Cells ◽  
Wound Repair ◽  
Transforming Growth Factor ◽  
Airway Epithelial ◽  
Airway Injury ◽  
Tgf Β1

In vivo, transforming growth factor (TGF)-β1 and matrix metalloproteinases (MMPs) present at the site of airway injury are thought to contribute to epithelial wound repair. As TGF-β1 can modulate MMP expression and MMPs play an important role in wound repair, we hypothesized that TGF-β1 may enhance airway epithelial repair via MMPs secreted by epithelial cells. We evaluated the in vitro influence of TGF-β1 on wound repair in human airway epithelial cells cultured under conditions allowing differentiation. The results showed that TGF-β1 accelerated in vitro airway wound repair, whereas MMP inhibitors prevented this acceleration. In parallel, we examined the effect of TGF-β1 on the expression of MMP-2 and MMP-9. TGF-β1 induced a dramatic increase of MMP-2 expression with an increased steady-state level of MMP-2 mRNA, contrasting with a slight increase in MMP-9 expression. To confirm the role of MMP-2, we subsequently evaluated the effect of MMP-2 on in vitro airway wound repair and demonstrated that the addition of MMP-2 reproduced the acceleration of wound repair induced by TGF-β1. These results strongly suggest that TGF-β1 increases in vitro airway wound repair via MMP-2 upregulation. It also raises the issue of a different in vivo biological role of MMP-2 and MMP-9 depending on the cytokine microenvironment.

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