Abstract 159: Androgen Deficiency Influences Matrix Metalloproteinase Expression and Intimal Hyperplasia Development After Vascular Injury

2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Brian M Freeman ◽  
Deidra J Mountain ◽  
Timothy C Brock ◽  
Jason R Chapman ◽  
Stacy S Kirkpatrick ◽  
...  
Keyword(s):  
Vascular Disease ◽  
Intimal Hyperplasia ◽  
Molecular Mechanisms ◽  
Dependent Manner ◽  
Androgen Deficiency ◽  
Post Injury ◽  
Inflammatory Signaling ◽  
Increased Risk

Objectives: Androgen deficiency (AD) is associated with increased risk of vascular disease, yet the molecular mechanisms remain unclear. Our group has previously shown testosterone regulates matrix metalloproteinases (MMP) in a dose-dependent manner in vitro. Here we investigated the role of AD and androgen replacement therapy (ART) on inflammatory cytokines and MMP-modulated intimal hyperplasia (IH) development in vivo. Methods: Aged orchiectomized (AO) rats were implanted with increasing doses of testosterone pellets (TST; 0.5-150mg). ELISA and multiplex array determined serum TST and cytokine levels. Young intact (YI), Aged intact (AI), and AO rats given placebo (Plac) or TST supplementation underwent balloon angioplasty of the left common carotid following 14d ART. Tissue samples were collected 14d post-injury for Intima:Media (I:M) or MMP quantification. Results: Therapeutic TST doses were achieved at 14d with 0.5, 2.5, 5, and 35mg pellets when compared to controls (Table 1). Interleukin family isoforms were elevated at sub-physiological TST levels but returned to control levels with physiological TST (Table 2). I:M was decreased in AI and physiological TST levels compared to YI (Fig 1). I:M was increased with sub- and supra-physiological TST. Injury-induced expression of MMP-2 was highest in AI and physiological TST conditions, though these values were not significant (Table 3). Analysis of other MMP isoforms is ongoing. Conclusions: We demonstrated that low testosterone levels increase interleukin inflammatory signaling, regulate MMP expression, and increase IH development in vivo. This effect is reversed by physiologic testosterone supplementation. AD could be playing a role in vascular disease via MMP regulatory mechanisms under the control of inflammatory signaling cascades. Future studies will examine targeted inhibition of inflammatory-modulated MMP mechanisms in the prevention of dysfunctional vascular remodeling.

Abstract 185: Androgen Deficiency-induced Hyperplasia Development is Attenuated by Physiological Testosterone Replacement Independent of Metabolite Dihydrotestosterone

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Junior Univers ◽  
Brian M Freeman ◽  
Deidra J Mountain ◽  
Stacy S Kirkpatrick ◽  
Joshua D Arnold ◽  
...  
Keyword(s):  
Estrogen Receptor ◽  
Hormone Replacement ◽  
Estrogen Therapy ◽  
In Vivo Model ◽  
Androgen Deficiency ◽  
Post Injury ◽  
Estrogen Receptor Signaling ◽  
Increased Risk

Objectives: Androgen deficiency (AD) is associated with increased risk of cardio- and peripheral vascular disease, yet the underlying biochemical mechanisms remain unclear. Systemically testosterone (TST) is enzymatically reduced to its more potent metabolite dihydrotestosterone (DHT) or is aromatized to estradiol, which differentially stimulate androgen and estrogen receptor-mediated pathways, respectively. We have previously demonstrated an inverse relationship between TST levels and the cellular processes of intimal hyperplasia (IH) in vitro. Here we investigated TST and DHT replacement in the attenuation of IH in an in vivo model of AD. Methods: Sub- to high physiologic levels of TST or DHT was administered via pellet implants in aged orchiectomized rats (0.5-5mg). Young intact (YI), aged intact (AI), and orchiectomized placebo (Plac) rats served as controls. After 14d hormone replacement rats underwent balloon angioplasty of the left common carotid. 14d post-injury animals were euthanized, systemic hormone levels were determined by ELISA and comparative weight analysis of androgen sensitive organs (Table 1), and carotid intima:media (I:M) was quantified. Results: I:M was decreased in AI animals and with higher physiological TST replacement compared to YI controls (Fig 1). I:M was higher in Plac, sub- and low-physiological TST animals and at all DHT levels. Conclusions: Aging and the normal reduction of TST was protective against IH when compared to young animals. However, pathological AD and sub-physiological hormone replacement increased IH. While physiological TST replacement attenuated this effect, equivalent DHT replacement was not protective, but instead exacerbated the hyperplastic response. Future studies will investigate if the protective effect of physiological TST replacement could be via its conversion to estradiol and downstream estrogen receptor signaling and if estrogen therapy attenuates IH in AD males.

scholarly journals Suppression of the TGF-β pathway by a macrolide antibiotic decreases fibrotic responses by ocular fibroblasts in vitro

2020 ◽  
Vol 7 (9) ◽  
pp. 200441
Author(s):  
Thomas Stahnke ◽  
Beata Gajda-Deryło ◽  
Anselm G. Jünemann ◽  
Oliver Stachs ◽  
Katharina A. Sterenczak ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Macrolide Antibiotic ◽  
Drug Repositioning ◽  
Dependent Manner ◽  
Glaucoma Filtration Surgery ◽  
Concentration Dependent Manner ◽  
Device Implantation

To elucidate and to inhibit post-surgical fibrotic processes after trabeculectomy in glaucoma therapy, we measured gene expression in a fibrotic cell culture model, based on transforming growth factor TGF-β induction in primary human tenon fibroblasts (hTFs), and used Connectivity Map (CMap) data for drug repositioning. We found that specific molecular mechanisms behind fibrosis are the upregulation of actins, the downregulation of CD34, and the upregulation of inflammatory cytokines such as IL6, IL11 and BMP6 . The macrolide antibiotic Josamycin (JM) reverses these molecular mechanisms according to data from the CMap, and we thus tested JM as an inhibitor of fibrosis. JM was first tested for its toxic effects on hTFs, where it showed no influence on cell viability, but inhibited hTF proliferation in a concentration-dependent manner. We then demonstrated that JM suppresses the synthesis of extracellular matrix (ECM) components. In hTFs stimulated with TGF-β1, JM specifically inhibited α-smooth muslce actin expression, suggesting that it inhibits the transformation of fibroblasts into fibrotic myofibroblasts. In addition, a decrease of components of the ECM such as fibronectin, which is involved in in vivo scarring, was observed. We conclude that JM may be a promising candidate for the treatment of fibrosis after glaucoma filtration surgery or drainage device implantation in vivo .

Nicotinamide Enhances the Polyploidization of Primary Megakaryocytes.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1366-1366
Author(s):  
Lisa M. Giammona ◽  
Eleftherios Papoutsakis ◽  
William M. Miller
Keyword(s):  
Dna Content ◽  
Molecular Mechanisms ◽  
Ex Vivo ◽  
Annexin V ◽  
Dependent Manner ◽  
Vitamin B3 ◽  
Ploidy Levels ◽  
High Ploidy

Abstract Megakaryocyte (Mk) maturation includes the development of polyploid cells via endomitosis. In vitro models of Mk differentiation can be used to gain a better understanding of the molecular mechanisms controlling this process. However, it is challenging to achieve ploidy levels in cultured human cells that are as high as those observed in vivo. Others have recently reported the use of chemical inhibitors to increase Mk ploidy (Lannutti et al., Blood 105:3875, 2005). Here, we show that nicotinamide (NIC), a form of vitamin B3, enhances the normal process of Mk polyploidization and leads to both a greater fraction of high ploidy cells and a greater degree of polyploidization. Human mobilized peripheral blood CD34+ cells were cultured in serum-free medium supplemented with thrombopoietin (TPO) to induce Mk differentiation. Beginning on day 5 of culture, cells were treated with nicotinamide (3 and 6.25 mM) and monitored for DNA content, growth, apoptosis, and surface marker expression. NIC treatment resulted in a greater fraction of Mks with high ploidy (DNA content greater than or equal to 8N). The ploidy of NIC treated cells continued to increase over the duration of the 13-day culture, whereas the ploidy of untreated cells peaked at day 9. On day 13 (8 days of NIC exposure), the percentages of high ploidy Mks for the untreated, 3 mM NIC, and 6.25 mM NIC conditions were 23%, 48%, and 63%, respectively. Furthermore, cells treated with NIC reached ploidy levels of 64N and 32N for 6.25 and 3 mM NIC, respectively, compared to 16N for untreated cells. NIC-treated cells also displayed dramatic differences in morphology - characterized by an increase in cell size, the presence of a more highly lobated nucleus, and an increased frequency of proplatelet-forming cells. Nicotinamide is known to inhibit poly(ADP-ribose) polymerase (PARP) and Sir2, which are both NAD+ dependent enzymes. Preliminary experiments show that PARP activity is low in cultured Mks and is not affected by addition of 6.25 mM NIC. Continued exposure (beginning at day 5) to the PARP inhibitors (and nicotinamide analogs) 3-aminobenzamide (3-AB) and benzamide at concentrations of 1, 3, and 6.25 mM was toxic to cells in a dose dependent manner. Interestingly, high doses of NIC (25 and 50 mM) were also toxic to cells. Remarkably, while Mk polyploidization and apoptosis are typically correlated, the increase in DNA content observed for NIC-treated cells occurred without significantly affecting the percentage of apoptotic Mks (assessed by Annexin V staining). These data suggest that it may be possible to partially decouple Mk apoptosis and polyploidization. Furthermore, while 6.25 mM NIC inhibited cell proliferation by ~35%, total expansion of cells cultured with 3 mM NIC was similar to that of untreated cells. This, combined with similar Mk commitment, as defined by a similar percentage of CD41+ cells, resulted in a greater overall number of high ploidy Mks in cultures treated with NIC. Since there is a direct correlation between Mk DNA content and platelet production (Mattia et al., Blood 99:888, 2002), these results suggest a possible therapeutic benefit of NIC for the management of thrombocytopenia. Similarly, NIC could also be used as an additive to ex vivo Mk cultures destined for transplantation. Figure Figure

GFI1 Is a Tumor Suppressor in Myeloid Progenitors

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 2942-2942
Author(s):  
Aditya Chaubey ◽  
Shane Hormon ◽  
Chinavenmeni S. Velu ◽  
Tristan Bourdeau ◽  
Jinfang Zhu ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Myeloid Leukemia ◽  
Dependent Manner ◽  
Loss Of Function ◽  
Increased Risk ◽  
Myeloid Leukemias ◽  
Dose Dependent ◽  
Anterior Posterior

Abstract In severe congenital neutropenia (SCN) patients and mice with Growth factor independent-1 (Gfi1) loss of function, arrested progenitors are suspended in a hyperproliferative state while terminal granulpoiesis is blocked. SCN patients are at increased risk for the development of acute myeloid leukemia. We demonstrate that Gfi1 directly targets HoxA9, Pbx1 and Meis1 during normal myelopoiesis. Gfi1−/− progenitors exhibit elevated levels of HoxA9, Pbx1 and Meis1, exaggerated HoxA9-Pbx1-Meis1 activity, and increased persistence in vivo and in vitro. Limiting HoxA9 alleles corrects, in a dose dependent manner, in vivo and in vitro phenotypes observed with loss of Gfi1. Moreover, in a manner conserved in Drosophila anterior/posterior patterning, we demonstrate that these factors can compete for occupancy of DNA sequences encoding composite Gfi1-HoxA9-Pbx1-Meis1 binding sites. Finally, the expression of Gfi1 and HoxA9 are inverse and stratify human myeloid leukemias, suggesting a role for HoxA9- Gfi1 antagonism in human AML. In agreement with this, a myeloproliferative disorder progresses into a rapid, lethal and transplantable myeloid leukemia in a Gfi1−/− setting. We conclude that the lifespan and oncogenic transformation of hematopoietic progenitor cells is regulated through a conserved competition between Gfi1 and HoxA9-Pbx1-Meis1.

scholarly journals Polygonatum sibiricum Polysaccharides Protect against MPP-Induced Neurotoxicity via the Akt/mTOR and Nrf2 Pathways

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Si Huang ◽  
Haiyan Yuan ◽  
Wenqun Li ◽  
Xinyi Liu ◽  
Xiaojie Zhang ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Neuronal Loss ◽  
Heme Oxygenase 1 ◽  
Related Factor ◽  
Dependent Manner ◽  
Quinone Oxidoreductase ◽  
Glutamate Cysteine Ligase ◽  
Dopaminergic Neuronal Loss

Polygonatum sibiricum, a well-known life-prolonging tonic in Chinese medicine, has been widely used for nourishing nerves in the orient, but the underlying molecular mechanisms remain unclear. In this study, we found that P. sibiricum polysaccharides (PSP) ameliorated 1-methyl-4-phenyl-1,2.3,6-tetrahydropyridine- (MPTP-) induced locomotor activity deficiency and dopaminergic neuronal loss in an in vivo Parkinson’s disease (PD) mouse model. Additionally, PSP pretreatment inhibited N-methyl-4-phenylpyridine (MPP+) induced the production of reactive oxygen species, increasing the ratio of reduced glutathione/oxidized glutathione. In vitro experiments showed that PSP promoted the proliferation of N2a cells in a dose-dependent manner, while exhibiting effects against oxidative stress and neuronal apoptosis elicited by MPP+. These effects were found to be associated with the activation of Akt/mTOR-mediated p70S6K and 4E-BP1 signaling pathways, as well as nuclear factor erythroid 2-related factor 2- (Nrf2-) mediated NAD(P)H quinone oxidoreductase 1 (NQO1), heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic subunit (Gclc), and glutamate-cysteine ligase modulatory subunit (Gclm), resulting in antiapoptotic and antioxidative effects. Meanwhile, PSP exhibited no chronic toxicity in C57BJ/6 mice. Together, our results suggest that PSP can serve as a promising therapeutic candidate with neuroprotective properties in preventing PD.

scholarly journals Recombinant Water Stress Protein 1 (Re-WSP1) Suppresses Colon Cancer Cell Growth Through Mir-539/Β-Catenin Signaling Pathway

2021 ◽  
Author(s):  
Songjia Guo ◽  
Shuhua Shan ◽  
Haili Wu ◽  
huiqiang hao ◽  
Zhuoyu Li
Keyword(s):  
Colon Cancer ◽  
Water Stress ◽  
Cell Growth ◽  
Molecular Mechanisms ◽  
Stress Protein ◽  
Pcr Analysis ◽  
Dependent Manner ◽  
Nostoc Commune

Abstract Nostoc commune Vauch is a nitrogen-fixing blue-green algae, contains a large number of active molecules with medicinal functions. Our previous study found that a water stress protein (WSP1) from Nostoc commune Vauch and its the recombinant protein (Re-WSP1) exhibited significant anti-colon cancer (CRC) activity both in vitro and in vivo. However, the underlying mechanism remains unknown. In this study, the CCK8 and clonogenic assays showed that Re-WSP1 restrained the colon cancer growth in a dose-dependent manner. Mechanistically, Re-WSP1 inhibited the expression of β-catenin, which was partly reversed by LiCl treatment, demonstrating a key role in Re-WSP1-induced inhibition of cell growth. Quantitative PCR analysis showed that the expression of microRNA-539 (miR-539) was significantly up-regulated upon Re-WSP1 treatment. Moreover, miR-539 negatively regulateed the expression of β-catenin through directly binds to the 3’UTR of β-catenin mRNA. Taken together, our data demonstrate that Re-WSP1 suppresses the CRC growth via miR-539/β-catenin axis, which provides new insights into the molecular mechanisms underlying Re-WSP1 against CRC.

scholarly journals Epigenetic regulation of ferroptosis via ETS1/miR-23a-3p/ACSL4 axis mediates sorafenib resistance in human hepatocellular carcinoma

2022 ◽  
Vol 41 (1) ◽  
Author(s):  
Yuanjun Lu ◽  
Yau-Tuen Chan ◽  
Hor-Yue Tan ◽  
Cheng Zhang ◽  
Wei Guo ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Drug Resistance ◽  
Molecular Mechanisms ◽  
Luciferase Reporter ◽  
Dependent Manner ◽  
Bioinformatics Analyses ◽  
Sorafenib Treatment ◽  
Hcc Cells

Abstract Background Drug resistance to sorafenib greatly limited the benefits of treatment in patients with hepatocellular carcinoma (HCC). MicroRNAs (miRNAs) participate in the development of drug resistance. The key miRNA regulators related to the clinical outcome of sorafenib treatment and their molecular mechanisms remain to be identified. Methods The clinical significance of miRNA-related epigenetic changes in sorafenib-resistant HCC was evaluated by analyzing publicly available databases and in-house human HCC tissues. The biological functions of miR-23a-3p were investigated both in vitro and in vivo. Proteomics and bioinformatics analyses were conducted to identify the mechanisms that regulating miR-23a-3p. Luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay were used to validate the binding relationship of miR-23a-3p and its targets. Results We found that miR-23a-3p was the most prominent miRNA in HCC, which was overexpressed in sorafenib non-responders and indicated poor survival and HCC relapse. Sorafenib-resistant cells exhibited increased miR-23a-3p transcription in an ETS Proto-Oncogene 1 (ETS1)-dependent manner. CRISPR-Cas9 knockout of miR-23a-3p improved sorafenib response in HCC cells as well as orthotopic HCC tumours. Proteomics analysis suggested that sorafenib-induced ferroptosis was the key pathway suppressed by miR-23a-3p with reduced cellular iron accumulation and lipid peroxidation. MiR-23a-3p directly targeted the 3′-untranslated regions (UTR) of ACSL4, the key positive regulator of ferroptosis. The miR-23a-3p inhibitor rescued ACSL4 expression and induced ferrotoptic cell death in sorafenib-treated HCC cells. The co-delivery of ACSL4 siRNA and miR-23a-3p inhibitor abolished sorafenib response. Conclusion Our study demonstrates that ETS1/miR-23a-3p/ACSL4 axis contributes to sorafenib resistance in HCC through regulating ferroptosis. Our findings suggest that miR-23a-3p could be a potential target to improve sorafenib responsiveness in HCC patients.

scholarly journals The Long Non-coding RNA TMPO-AS1  Promotes Bladder Cancer Growth and Progression via OTUB1-induced E2F1 Deubiquitination

2020 ◽  
Author(s):  
Yeyu Zhang ◽  
Yuxing Zhu ◽  
Mengqing Xiao ◽  
Yaxin Cheng ◽  
Dong He ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Molecular Mechanisms ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Dependent Manner ◽  
E2f Transcription Factor ◽  
Rna Immunoprecipitation ◽  
Regulatory Loop

Abstract BackgroundBladder cancer (BC) is the most common malignant tumor of the urinary system. Increasing evidence indicates long non-coding RNAs (lncRNAs) play crucial roles in cancer tumorigenesis, development, and progression. However, the role of TMPO antisense RNA 1 (TMPO-AS1) is still need to be explored in BC.MethodsThe lncRNA TMPO-AS1 expression was evaluated by bioinformatics analysis and further validated by qRT-PCR. Loss- and gain-of- function assays were performed to determine the biological functions of TMPO-AS1 in BC proliferation, migration, and invasion. Chromatin immunoprecipitation, luciferase reporter assays, western blotting, RNA pull-down, RNA immunoprecipitation assays, and fluorescence in situ hybridization were conducted to explore the molecular mechanisms of TMPO-AS1/E2F transcription factor 1 (E2F1) loop. ResultsTMPO-AS1 is upregulated in bladder cancer and is associated with BC patients’ poor prognoses. Functional experiments demonstrated that TMPO-AS1 promotes bladder cancer cell proliferation, migration, invasion, and inhibits cell apoptosis in vivo and in vitro. Mechanically, E2F1 is responsible for the TMPO-AS1 upregulation. Additionally, TMPO-AS1 facilitates the interaction of E2F1 with OTU domain-containing ubiquitin aldehyde binding 1 (OTUB1), leading to E2F1 deubiquitination and stabilization, thereby promotes BC malignant phenotypes. Furthermore, rescue experiments showed that TMPO-AS1 promotes BC growth in an E2F1-dependent manner.ConclusionsOur study is the first to uncover a novel positive regulatory loop of TMPO-AS1/E2F1 important for the promotion of BC malignant behaviors. The TMPO-AS1/E2F1 loop should be considered in the quest for new BC therapeutic options.

scholarly journals Advanced in Molecular Mechanisms of Atherosclerosis: From Lipids to Inflammation

2018 ◽  
Vol 10 (2) ◽  
pp. 104-22 ◽  
Author(s):  
Anna Meiliana ◽  
Nurrani Mustika Dewi ◽  
Andi Wijaya
Keyword(s):  
Vascular Disease ◽  
Blood Vessels ◽  
Molecular Mechanisms ◽  
Vascular Dysfunction ◽  
In Vivo Studies ◽  
Disease States ◽  
Fibrous Cap ◽  
Plaque Disruption

BACKGROUND: Atherosclerosis is a leading cause of vascular disease worldwide. During the past several decades, landmark discoveries in the field of vascular biology have evolved our understanding of the biology of blood vessels and the pathobiology of local and systemic vascular disease states and have led to novel disease-modifying therapies for patients. This review is made to understand the molecular mechanism of atherosclerosis for these future therapies.CONTENT: Advances in molecular biology and -omics technologies have facilitated in vitro and in vivo studies which revealed that blood vessels regulate their own redox milieu, metabolism, mechanical environment, and phenotype, in part, through complex interactions between cellular components of the blood vessel wall and circulating factors. Dysregulation of these carefully orchestrated homeostatic interactions has also been implicated as the mechanism by which risk factors for cardiopulmonary vascular disease lead to vascular dysfunction, structural remodeling and, ultimately, adverse clinical events.SUMMARY: Atherosclerosis is a heterogeneous disease, despite a common initiating event of apoB-lipoproteins. Despite of acute thrombotic complications, an adequate resolution response is mounted, where efferocytosis prevents plaque necrosis and a reparative scarring response (the fibrous cap) prevents plaque disruption. However, a small percentage of developing atherosclerotic lesions cannot maintain an adequate resolution response, which leading to the formation of clinically dangerous plaques that can trigger acute lumenal thrombosis and tissue ischemiaand infarction.KEYWORDS: atherosclerosis, oxidative stress, inflammation, efferocytosis, foam cells, thrombosis

A Comparative Study of the Effects of Adrenoceptor Antagonists on Platelet Aggregation and Thromboxane Generation

1985 ◽  
Vol 54 (02) ◽  
pp. 480-484 ◽  
Author(s):  
I A Greer ◽  
J J Walker ◽  
M McLaren ◽  
A A Calder ◽  
C D Forbes
Keyword(s):  
Platelet Aggregation ◽  
Vascular Disease ◽  
Platelet Rich Plasma ◽  
Thromboxane A2 ◽  
Inhibitory Effect ◽  
Dependent Manner ◽  
Wide Range ◽  
The Right

SummaryPlatelet aggregation and thromboxane A2 have been implicated in the pathogenesis of several forms of vascular disease. The aim of this study was to determine the effect of a wide range of adrenoceptor antagonists on platelet aggregation, and thromboxane A2 production, from normal human platelet rich plasma in vitro. Labetalol, pindolol and propranolol inhibited platelet aggregation to collagen in a dose dependent manner. Increasing the concentration of collagen “shifted” the dose response curve to the right. These 3 drugs also significantly inhibited thromboxane A2 generation in response to collagen but not to arachidonic acid. This effect was independent of any inhibitory effect of these drugs on platelet aggregation, and occurred at a drug concentration close to that obtained in vivo. Atenolol, metoprolol, prazosin and timolol were similarly assessed but had no effect on either platelet aggregation or thromboxane A2 generation. This ability of labetalol, pindolol, and propranolol to inhibit platelet aggregation and thromboxane generation, may be of clinical benefit in view of the increasing evidence implicating thromboxane A2 in the pathogenesis of vascular disease.

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