scholarly journals Cimifugin Suppresses NF-κB Signaling to Prevent Osteoclastogenesis and Periprosthetic Osteolysis

2021 ◽  
Vol 12 ◽  
Author(s):  
Juan Duan ◽  
Xuantao Hu ◽  
Tao Li ◽  
Gen Wu ◽  
Pengcheng Dou ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Western Blot ◽  
Signaling Pathway ◽  
Osteoclast Differentiation ◽  
Mapk Signaling ◽  
Luciferase Reporter ◽  
Pcr Analysis ◽  
Periprosthetic Osteolysis

Background: Aseptic loosening of prosthesis (ALP) is one of the most common long-term complications of knee and hip arthroplasty. Wear particle-induced osteoclastogenesis and subsequent periprosthetic osteolysis account for the morbidity of ALP. Here, we investigate the potential of cimifugin (CIM), a natural extract from Cimicifuga racemosa and Saposhnikovia divaricata, as a bone-protective drug in the treatment of ALP.Method: First, we performed cell viability and osteoclast formation assays to assess the effect of noncytotoxic CIM on osteoclast differentiation in vitro. Bone slice resorption and F-actin ring immunofluorescence assays were adopted to assess the effects of CIM on bone-resorption function. Then, quantitative real-time polymerase chain reaction (qRT–PCR) analysis was performed to further assess the repressive effects of CIM on osteoclastogenesis at the gene expression level. To elucidate the mechanisms underlying the above findings, Western blot and luciferase reporter gene assays were used to assess the regulatory effects of CIM on the NF-κB and MAPK signaling pathways. Moreover, a Ti particle-induced murine calvarial osteolysis model and subsequent histomorphometric analysis via micro-CT and immunohistochemical staining were used to elucidate the effect of CIM on periprosthetic osteolysis in vivo.Result: CIM dose-dependently inhibited both bone marrow-derived macrophage (BMM)- and RAW264.7 cell-derived osteoclastogenesis and bone resorption pit formation in vitro, which was further supported by the reduced expression of F-actin and osteoclast-specific genes. According to the Western blot analysis, inhibition of IκBα phosphorylation in the NF-κB signaling pathway, not the phosphorylation of MAPKs, was responsible for the suppressive effect of CIM on osteoclastogenesis. Animal experiments demonstrated that CIM alleviated Ti particle-induced bone erosion and osteoclast accumulation in murine calvaria.Conclusion: The current study suggested for the first time that CIM can inhibit RANKL-induced osetoclastogenesis by suppressing the NF-κB signaling pathway in vitro and prevent periprosthetic osteolysis in vivo. These findings suggest the potential of CIM as a therapeutic in ALP.

scholarly journals Cimifugin Suppresses NF-κB Signaling to Prevent Osteoclastogenesis and Periprosthetic Osteolysis

2021 ◽  
Author(s):  
Juan Duan ◽  
Xuantao Hu ◽  
Tao Li ◽  
Pengcheng Dou
Keyword(s):  
Signaling Pathway ◽  
Western Blotting ◽  
Bone Erosion ◽  
Osteoclast Differentiation ◽  
Luciferase Reporter ◽  
Pcr Analysis ◽  
Periprosthetic Osteolysis ◽  
Gene Assay

Abstract Background: Aseptic loosening of prosthesis (ALP) is one of the most common long-term complication of knee and hip arthroplasty. Wear paticle-induced osteoclastogenesis and subsequent periprosthetic osteolysis accounts for the morbidity of ALP. Here, we investigate cimifugin (CIM), a natural extract from Cimicifuga Racemosa and Saposhnikovia Divaricata, as a bone protective drug in treatment of ALP.Method: First, we deployed cell viability and osteoclast formation assays to detect the effect of noncytotoxic CIM on osteoclast differentiation in vitro. Bone slice resorption evaluation and F-actin ring immunofluorescence assays were adopted to measure bone-resorbing function affected by CIM. Then, we introduce quantitative real-time polymerase chain reaction (qRT-PCR) analysis to further identify the repressed osteoclastogenesis by CIM in gene expression level. To reveal underlying mechanism of findings above, we used Western blotting and luciferase reporter gene assay to determine the regulation manner of CIM in NF-κB and MAPKs signaling pathways. Moreover, Ti particle-induced murine calvarial osteolysis model and following histomorphometric analysis via micro-CT and immunohistochemical staining were used to demonstrate the effect of CIM on periprosthetic osteolysis in vivo. Result: CIM administration dose-dependently inhibited both bone marrow-derived macrophages (BMMs) and RAW264.7 cells derived osteoclastogenesis and bone resorption pit formation in vitro, which further supported by reduced expression of F-actin and osteoclast specific genes. According to the Western blotting analysis, inhibition of IkBa phosphorylation in NF-κB signaling pathway, not the phosphorylation of MAPKs, was detected as the suppressive effect of CIM on osteoclastogenesis. In vivo animal experiment demonstrated that CIM alleviated Ti particle-induced bone erosion and osteoclast accumulation in murine calvaria. Conclusion: The current study for the first time proved that CIM could dose-dependently inhibit RANKL-induced osetoclastogenesis via suppressing NF-κB signaling pathway in vitro and prevent periprosthetic osteolysis in vivo. These findings suggest the potential therapeutic use of CIM in ALP.

scholarly journals Tussilagone Inhibits Osteoclastogenesis and Periprosthetic Osteolysis by Suppressing the NF-κb and p38 MAPK Signaling Pathways

2019 ◽  
Author(s):  
Xuantao Hu ◽  
Zhengxiao Ouyang ◽  
Dan Peng ◽  
Ziqing Yin ◽  
Xia Chen ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Signaling Pathways ◽  
P38 Mapk ◽  
Western Blotting ◽  
Mapk Signaling ◽  
Luciferase Reporter ◽  
Periprosthetic Osteolysis ◽  
Prosthetic Loosening ◽  
Mapk Signaling Pathways

Abstract Backgroud: Aseptic prosthetic loosening is one of main factor producing poor prognosis of limb function after joint replacement and requiring troublesome revision surgery. It is featured by wear particle–induced periprosthetic osteolysis mediated by excessive osteoclasts activated in inflammatory cell context. In our previous study, some natural compounds showing anti-osteoclast trait with high cost-efficiency and few side effects. Tussilagone (TUS), as the main functional extract from Tussilago Farfara precedently used for relieving cough, asthma and eliminating phlegm in traditional medicine, has been proved to appease several RAW264.7-mediated inflammatory diseases via suppressing osteoclast-related signaling cascades. However, whether and how TUS can improve aseptic prosthetic loosening via modulating osteoclast-mediated bone resorption still need to be answered. Methods: We established a murine calvarial osteolysis model to detect the preventative effect of TUS on osteolysis in vivo. Micro-CT scanning and histomorphometric analysis were used to determine the variation of bone resorption and osteoclastogenesis in samples. The anti-osteoclast-differentiation and anti-bone-resorption bioactivities of TUS in vitro were investigated using bone slice resorption pit evaluation and interference caused by cytotoxicity of TUS was excluded according to CCK-8 assay. Quantitative PCR analysis was applied to prove the decreased expression of osteoclast-specific genes after TUS treatment. The inhibition effect of TUS on NF-κb and p38 MAPK signaling pathways was testified by western blotting and NF-κB-linked luciferase reporter gene assay.Results: TUS demonstrated bone protective effect against osteolysis in murine calvarial osteolysis model with reduced osteoclasts compared to the control group. Following studies in vitro witnessed that TUS exert anti-osteoclastogenesis and anti-bone-resorption effects in both BMMs and RAW264.7 cells, as evidenced by the decline of osteoclast specific genes according to quantative PCR. Western blotting revealed that TUS-treated demonstrated inhibited IκBα degradation and p38 phosphorylation.Conclusions: Collectively, for the first time our studies prove that TUS inhibits osteoclastogenesis by suppressing the NF-κb and p38 MAPK signaling pathways, therefore serving as a potential natural compound to treat periprosthetic osteolysis-induced aseptic prosthetic loosening.

scholarly journals TRF-Val-CAC-016 Modulates the Transduction of CACNA1d-Mediated MAPK Signaling Pathways to Suppress the Proliferation of Gastric Carcinoma

2022 ◽  
Author(s):  
Weiguo Xu ◽  
Junyu Zheng ◽  
Xiao Wang ◽  
Bin Zhou ◽  
Huanqiu Chen ◽  
...  
Keyword(s):  
Gastric Carcinoma ◽  
Signaling Pathways ◽  
Signaling Pathway ◽  
Mapk Signaling ◽  
Mapk Signaling Pathway ◽  
Luciferase Reporter ◽  
Trna Derivatives ◽  
Mapk Signaling Pathways

Abstract Background: As a new kind of non-coding RNAs (ncRNAs), tRNA derivatives play an important role in gastric carcinoma (GC). Nevertheless, the underlying mechanism tRNA derivatives were involved in was rarely illustrated. Methods: We screened out the tRNA derivative, tRF-Val-CAC-016, based on the tsRNA sequencing and demonstrated the effect tRF-Val-CAC-016 exerted on GC proliferation in vitro and in vivo. We applied Dual-luciferase reporter assay, RIP assay, and bioinformatic analysis to discover the downstream target of tRF-Val-CAC-016. Then CACNA1d was selected, and the oncogenic characteristics were verified. Subsequently, we detected the possible regulation of the canonical MAPK signaling pathway to further explore the downstream mechanism of tRF-Val-CAC-016. Results: As a result, we found that tRF-Val-CAC-016 was low-expressed in GC, and upregulation of tRF-Val-CAC-016 could significantly suppress the proliferation of GC cell lines. Meanwhile, tRF-Val-CAC-016 regulated the canonical MAPK signaling pathway by targeting CACNA1d. Conclusions: tRF-Val-CAC-016 modulates the transduction of CACNA1d-mediated MAPK signaling pathways to suppress the proliferation of gastric carcinoma. This study discussed the function and mechanism of tRF-Val-CAC-016 in GC for the first time. The pioneering work has contributed to our present understanding of tRNA derivative, which might provide an alternative mean for the targeted therapy of GC.

scholarly journals Biological Effects of β-Glucans on Osteoclastogenesis

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1982
Author(s):  
Wataru Ariyoshi ◽  
Shiika Hara ◽  
Ayaka Koga ◽  
Yoshie Nagai-Yoshioka ◽  
Ryota Yamasaki
Keyword(s):  
Bone Resorption ◽  
Bone Marrow Cells ◽  
Biological Effects ◽  
Osteoclast Differentiation ◽  
Treatment Strategies ◽  
Alcaligenes Faecalis ◽  
Osteoclast Formation ◽  
Osteoclast Precursors

Although the anti-tumor and anti-infective properties of β-glucans have been well-discussed, their role in bone metabolism has not been reviewed so far. This review discusses the biological effects of β-glucans on bone metabolisms, especially on bone-resorbing osteoclasts, which are differentiated from hematopoietic precursors. Multiple immunoreceptors that can recognize β-glucans were reported to be expressed in osteoclast precursors. Coordinated co-stimulatory signals mediated by these immunoreceptors are important for the regulation of osteoclastogenesis and bone remodeling. Curdlan from the bacterium Alcaligenes faecalis negatively regulates osteoclast differentiation in vitro by affecting both the osteoclast precursors and osteoclast-supporting cells. We also showed that laminarin, lichenan, and glucan from baker’s yeast, as well as β-1,3-glucan from Euglema gracilisas, inhibit the osteoclast formation in bone marrow cells. Consistent with these findings, systemic and local administration of β-glucan derived from Aureobasidium pullulans and Saccharomyces cerevisiae suppressed bone resorption in vivo. However, zymosan derived from S. cerevisiae stimulated the bone resorption activity and is widely used to induce arthritis in animal models. Additional research concerning the relationship between the molecular structure of β-glucan and its effect on osteoclastic bone resorption will be beneficial for the development of novel treatment strategies for bone-related diseases.

scholarly journals Oncogene APOL1 promotes proliferation and inhibits apoptosis via activating NOTCH1 signaling pathway in pancreatic cancer

2021 ◽  
Vol 12 (8) ◽  
Author(s):  
Jiewei Lin ◽  
Zhiwei Xu ◽  
Junjie Xie ◽  
Xiaxing Deng ◽  
Lingxi Jiang ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Signaling Pathway ◽  
Density Lipoprotein ◽  
Human Pancreatic Cancer ◽  
Luciferase Reporter ◽  
Notch1 Signaling ◽  
In Vivo Experiments ◽  
Notch1 Signaling Pathway

AbstractAPOL1 encodes a secreted high-density lipoprotein, which has been considered as an aberrantly expressed gene in multiple cancers. Nevertheless, the role of APOL1 in the regulatory mechanisms of pancreatic cancer remains unknown and should be explored. We identified APOL1 was abnormally elevated in human pancreatic cancer tissues compared with that in adjacent tissues and was associated with poor prognosis. The effects of APOL1 in PC cell proliferation, cell cycle, and apoptosis was verified via functional in vitro and in vivo experiments. The results showed that knockdown of APOL1 significantly inhibited the proliferation and promoted apoptosis of pancreatic cancer. In addition, we identified APOL1 could be a regulator of NOTCH1 signaling pathway using bioinformatics tools, qRT-PCR, dual-luciferase reporter assay, and western blotting. In summary, APOL1 could function as an oncogene to promote proliferation and inhibit apoptosis through activating NOTCH1 signaling pathway expression in pancreatic cancer; therefore, it may act as a novel therapeutic target for pancreatic cancer.

scholarly journals Periplaneta Americana Extract may Attenuate 2,4,6-Trinitrobenzenesulfonic Acid-Induced Intestinal Fibrosis by Inhibiting TGF-β/Smad Signaling Pathway

2021 ◽  
Author(s):  
Jing Liu ◽  
Pin Lv ◽  
Xiang Rao ◽  
Jiajia Wang
Keyword(s):  
Western Blot ◽  
Signaling Pathway ◽  
Real Time Pcr ◽  
Periplaneta Americana ◽  
Collagen I ◽  
Smad Signaling ◽  
Intestinal Fibrosis ◽  
Smad Signaling Pathway

Abstract PurposeIntestinal fibrosis is an incurable digestive disease accompanied by stricture formation, and it has an increasing incidence in recent years. Periplaneta americana is one of the medicinal insects with a long history. There are few reports on the effect of intestinal fibrosis. This study aims to evaluate the inhibitory effect of PA treatment on intestinal fibrosis. MethodsTNBS was used to establish intestinal fibrosis model by enema in BALB/c mice. The mice were treated with PA (50, 100, 200 mg/kg body weight) and 5-aminosalicylic acid (5-ASA) (40mg/kg) by gavage once a day for 6 weeks. At the end of the last week, the mice were sacrificed. Colon samples were collected for H&E and Masson staining. The mRNA and protein expression of α-smooth muscle actin (α-SMA), collagen I and the transforming growth factor-β (TGF-β) / Smad signaling pathway were conducted by real-time PCR and western blot analysis. In vitro, TGF-β1 was used to induce intestinal fibrosis at human colon fibroblasts (CCD-18Co). And using real-time PCR and western blot methods to detect the expression of α-SMA and collagen I. ResultsPA inhibited the expression of α-SMA and collagen I in vivo and in vitro. But the difference was that PA inhibited the TGF-β/Smad signaling pathway in vivo, and the same results had not been obtained in vitro. Conclusion: PA may attenuate intestinal fibrosis by inhibiting TGF-β/Smad signaling pathway, but more experiments were needed to prove it in vitro. ConclusionsPA has potential pharmacological effects in inhibiting intestinal fibrosis, and the TGF-β/Smad signaling pathway seemed promising.

scholarly journals The effect of strontium ranelate on titanium particle-induced periprosthetic osteolysis regulated by WNT/β-catenin signaling in vivo and in vitro

2021 ◽  
Vol 41 (1) ◽  
Author(s):  
Bolun Wang ◽  
Haohui Guo ◽  
Tianxiang Geng ◽  
Kening Sun ◽  
Liang Zhang ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Aseptic Loosening ◽  
Cell Line ◽  
Conditioned Medium ◽  
Strontium Ranelate ◽  
Cell Model ◽  
Periprosthetic Osteolysis ◽  
A Cell

Abstract Aseptic loosening following periprosthetic osteolysis is the primary complication that limits the lifetime of total joint arthroplasty (TJA). The wear particles trigger a chronic inflammation response in the periprosthetic tissue and turn over the bone balance to bone resorption. The present study aimed to investigate the possible effect and mechanism of strontium ranelate (SR), a clinically safe drug for osteoporosis, on particle-induced periprosthetic osteolysis. Thirty-six female C57BL/6j mice underwent tibial Ti-nail implantation to establish an animal model of aseptic loosening. After 12 weeks, micro-CT results showed that strontium ranelate could inhibit periprosthetic bone resorption. In vitro, Ti particles were used to stimulate RAW264.7 cell line to collect conditioned medium, and co-culture MC3T3-E1 cell line with conditioned medium to establish a cell model of aseptic loosening. The results of alkaline phosphatase (ALP) detection, immunofluorescence, and flow cytometry demonstrated that strontium ranelate could regulate the expression of OPG/RANKL, promote differentiation and mineralization, and inhibit apoptosis in osteoblasts. Moreover, we revealed that SR’s exerted its therapeutic effect by down-regulating sclerostin, thereby activating the Wnt/β-catenin signal pathway. Therefore, this research suggests that strontium ranelate could be a potential drug for the prevention and treatment of particle-induced aseptic loosening post-TJA.

scholarly journals Has-miR-875-5p Inhibits Tumorigenesis by Targeting USF2 via TGF-β Signaling Pathway in Gastric Cancer

2021 ◽  
Author(s):  
Shenshuo Gao ◽  
Zhikai Zhang ◽  
Xubin Wang ◽  
Yan Ma ◽  
Chensheng Li ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Signaling Pathway ◽  
Research Direction ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Gastric Cancer Cells ◽  
New Research

Abstract Background: Gastric cancer (GC) is one of the most common malignancies, and more and more evdiences show that the pathogenesis is regulated by various miRNAs.In this study, we investigated the role of miR-875 in GC. Methods:The expression of miR-875-5p was detected in human GC specimens and cell lines by miRNA RT-PCR. The effect of miR-875-5p on GC proliferation was determined by CCK-8 proliferation assay and EDU assay. Migration and invasion were examined by transwell migration and invasion assay and wound healing assay. The interaction between miR-875-5p and its target gene USF2 was verified by a dual luciferase reporter assay. The effects of miR-875-5p in vivo were studied in xenograft nude mice models.Related proteins were detected by Western blot.Results:The results showed that miR-875-5p inhibited the proliferation, migration and invasion of gastric cancer cells in vitro, and inhibited tumorigenesis in vivo. USF2 proved to be a direct target of miR-875-5p. Knockdown of USF2 partially counteracts the effects of miR-875-5p inhibitors.Overexpression of miR-875-5p can inhibit proliferation, migration, and invasion through the TGF-β signaling pathway by down-regulation of USF2 in GC, providing a new research direction for the diagnosis and targeted therapy of GC.Conclusions: MiR-875-5pcan inhibited the progression of GC by directly targeting USF2 and negatively regulating TGF-β signaling pathway.In the future, miR-875-5p is expected to be used as a potential therapeutic target for GC therapy.

scholarly journals Network Pharmacology-Based Strategy for the Investigation of the Anti-Osteoporosis Effects and Underlying Mechanism of Zhuangguguanjie Formulation

2021 ◽  
Vol 12 ◽  
Author(s):  
Wang Gong ◽  
Xingren Chen ◽  
Tianshu Shi ◽  
Xiaoyan Shao ◽  
Xueying An ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Bone Formation ◽  
Bone Mass ◽  
Signaling Pathway ◽  
Osteoclast Differentiation ◽  
Enrichment Analysis ◽  
Underlying Mechanism ◽  
Network Pharmacology ◽  
Biological Processes

As the society is aging, the increasing prevalence of osteoporosis has generated huge social and economic impact, while the drug therapy for osteoporosis is limited due to multiple targets involved in this disease. Zhuangguguanjie formulation (ZG) is extensively used in the clinical treatment of bone and joint diseases, but the underlying mechanism has not been fully described. This study aimed to examine the therapeutic effect and potential mechanism of ZG on postmenopausal osteoporosis. The ovariectomized (OVX) mice were treated with normal saline or ZG for 4 weeks after ovariectomy following a series of analyses. The bone mass density (BMD) and trabecular parameters were examined by micro-CT. Bone remodeling was evaluated by the bone histomorphometry analysis and ELISA assay of bone turnover biomarkers in serum. The possible drug–disease common targets were analyzed by network pharmacology. To predict the potential biological processes and related pathways, GO/KEGG enrichment analysis was performed. The effects of ZG on the differentiation phenotype of osteoclasts and osteoblasts and the predicted pathway were verified in vitro. The results showed that ZG significantly improved the bone mass and micro-trabecular architecture in OVX mice compared with untreated OVX mice. ZG could promote bone formation and inhibit bone resorption to ameliorate ovariectomy-induced osteoporosis as evidenced by increased number of osteoblast (N.Ob/Tb.Pm) and decreased number of osteoclast (N.Oc/Tb.Pm) in treated group compared with untreated OVX mice. After identifying potential drug–disease common targets by network pharmacology, GO enrichment analysis predicted that ZG might affect various biological processes including osteoblastic differentiation and osteoclast differentiation. The KEGG enrichment analysis suggested that PI3K/Akt and mTOR signaling pathways could be the possible pathways. Furthermore, the experiments in vitro validated our findings. ZG significantly down-regulated the expression of osteoclast differentiation markers, reduced osteoclastic resorption, and inhibited the phosphorylation of PI3K/Akt, while ZG obviously up-regulated the expression of osteogenic biomarkers, promoted the formation of calcium nodules, and hampered the phosphorylation of 70S6K1/mTOR, which can be reversed by the corresponding pathway activator. Thus, our study suggested that ZG could inhibit the PI3K/Akt signaling pathway to reduce osteoclastic bone resorption as well as hamper the mTORC1/S6K1 signaling pathway to promote osteoblastic bone formation.

scholarly journals An Integration of Network Pharmacology and Experimental Verification to Investigate the Mechanism of Guizhi to Treat Nephrotic Syndrome

2021 ◽  
Vol 12 ◽  
Author(s):  
Dan He ◽  
Qiang Li ◽  
Guangli Du ◽  
Guofeng Meng ◽  
Jijia Sun ◽  
...  
Keyword(s):  
Nephrotic Syndrome ◽  
Molecular Docking ◽  
Protein Expression ◽  
Signaling Pathway ◽  
P38 Mapk ◽  
Experimental Verification ◽  
Active Component ◽  
Mapk Signaling

Background: Guizhi has the pharmacological activity of anti-inflammatory. However, the effect mechanism of Guizhi against nephrotic syndrome (NS) remains unclear. A network pharmacological approach with experimental verification in vitro and in vivo was performed to investigate the potential mechanisms of Guizhi to treat NS.Methods: Active compounds and potential targets of Guizhi, as well as the related targets of NS were obtained from the public databases. The intersecting targets of Guizhi and NS were obtained through Venny 2.1.0. The key targets and signaling pathways were determined by protein-protein interaction (PPI), genes ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analysis. And the overall network was constructed with Cytoscape. Molecular docking verification was carried out by AutoDock Vina. Finally, in vitro and in vivo experiments were performed to verify the mechanism of Guizhi to treat NS.Results: 63 intersecting targets were obtained, and the top five key targets mainly involed in NF- Kappa B and MAPK signaling pathway. In the overall network, cinnamaldehyde (CA) was the top one active compound with the highest degree value. The molecular docking showed that the top five key targets were of good binding activity with the active components of Guizhi. To in vitro experiment, CA, the main active component of Guizhi, inhibited the secretion of IL-1β, IL-6, TNF-α in LPS challenged RAW264.7 cells, and down regulated the protein expression of p-NF-κB p65 and p-p38 MAPK in LPS challenged RAW264.7 cells. In vitro experiment showed that, 24 urinary protein and renal function were increased in ADR group. To western blot, CA down regulated the protein expression of p-p38 MAPK in rats of adriamycin-induced nephropathy.Conclusion: CA might be the main active component of Guizhi to treat NS, and the underlying mechanism might mainly be achieved by inhibiting MAPK signaling pathway.

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