Attenuation of subarachnoid hemorrhage–induced apoptotic cell death with 17 beta-estradiol

2009 ◽  
Vol 111 (5) ◽  
pp. 1014-1022 ◽  
Author(s):  
Chih-Lung Lin ◽  
Aaron S. Dumont ◽  
Yu-Feng Su ◽  
Zen-Kong Dai ◽  
Juei-Tang Cheng ◽  
...  
Keyword(s):  
Cell Death ◽  
Estrogen Receptor ◽  
Subarachnoid Hemorrhage ◽  
Protein Expression ◽  
Dentate Gyrus ◽  
Caspase 3 ◽  
Tunel Staining ◽  
Secondary Brain Injury ◽  
Ici 182,780 ◽  
Tnf Α

Object Apoptosis is implicated in vasospasm and long-term sequelae of subarachnoid hemorrhage (SAH). The authors observed that 17β-estradiol (E2) can attenuate cerebral vasospasm, lower endothelin-1 production, and preserve normal endothelial nitric oxide synthase expression by reduction of inducible NO synthase expression in experimental SAH. The authors investigated the potential antiapoptotic effects of E2 in an experimental rat model of SAH. Methods The authors examined the antiapoptotic effects of E2 in a double-hemorrhage SAH model in male Sprague-Dawley rats. The rats underwent subcutaneous implantation of a Silastic tube containing corn oil either with or without E2, and some E2-treated animals also received ICI 182,780 (a nonselective estrogen receptor [ER] antagonist) for 7 days after SAH. The degree of vasospasm was determined by averaging the cross-sectional areas of the basilar artery 7 days after SAH. The expression of apoptotic indicators, including TNF-α, caspase 3, Bcl-2, Bax, terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling (TUNEL), and cell death assays were used for detection of apoptosis. Results Treatment with E2 significantly attenuated SAH-induced vasospasm. Seven days after the induction of SAH, positive TUNEL-staining was seen, and DNA fragmentation was increased in the dentate gyrus. Increased TNF-α and cleaved caspase-3 protein expression and decreased Bcl-2 protein expression in the dentate gyrus were also observed. These changes were reversed with E2-treatment but not in the presence of ICI 182,780. However, the expression of Bax did not change after SAH either with or without E2 treatment. Conclusions The authors found that E2 appears to confer an antiapoptotic effect that reduces secondary brain injury after SAH via estrogen receptor–dependent mechanisms. This finding provides support for possible future applications of E2 treatment for the reduction of secondary injury after SAH in patients.

Increased cell death in osteopontin-deficient cardiac fibroblasts occurs by a caspase-3-independent pathway

2004 ◽  
Vol 287 (4) ◽  
pp. H1730-H1739 ◽  
Author(s):  
Ron Zohar ◽  
Baoqian Zhu ◽  
Peter Liu ◽  
Jaro Sodek ◽  
C. A. McCulloch
Keyword(s):  
Cell Death ◽  
Caspase 3 ◽  
Cardiac Fibroblasts ◽  
Chromatin Condensation ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Tunel Staining ◽  
Wild Type ◽  
Nuclear Fragmentation ◽  
A Cell

Reperfusion-induced oxidative injury to the myocardium promotes activation and proliferation of cardiac fibroblasts and repair by scar formation. Osteopontin (OPN) is a proinflammatory cytokine that is upregulated after reperfusion. To determine whether OPN enhances fibroblast survival after exposure to oxidants, cardiac fibroblasts from wild-type (WT) or OPN-null (OPN−/−) mice were treated in vitro with H2O2to model reperfusion injury. Within 1 h, membrane permeability to propidium iodide (PI) was increased from 5 to 60% in OPN−/−cells but was increased to only 20% in WT cells. In contrast, after 1–8 h of treatment with H2O2, the percent of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-stained cells was more than twofold higher in WT than OPN−/−cells. Electron microscopy of WT cells treated with H2O2showed chromatin condensation, nuclear fragmentation, and cytoplasmic and nuclear shrinkage, which are consistent with apoptosis. In contrast, H2O2-treated OPN−/−cardiac fibroblasts exhibited cell and nuclear swelling and membrane disruption that are indicative of cell necrosis. Treatment of OPN−/−and WT cells with a cell-permeable caspase-3 inhibitor reduced the percentage of TUNEL staining by more than fourfold in WT cells but decreased staining in OPN−/−cells by ∼30%. Although the percentage of PI-permeable WT cells was reduced threefold, the percent of PI-permeable OPN−/−cells was not altered. Restoration of OPN expression in OPN−/−fibroblasts reduced the percentage of PI-permeable cells but not TUNEL staining after H2O2treatment. Thus H2O2-induced cell death in OPN-deficient cardiac fibroblasts is mediated by a caspase-3-independent, necrotic pathway. We suggest that the increased expression of OPN in the myocardium after reperfusion may promote fibrosis by protecting cardiac fibroblasts from cell death.

scholarly journals Pituitary Adenylate Cyclase Activating Polypeptide Elicits Neuroprotection Against Acute Ischemic Neuronal Cell Death Associated with NMDA Receptors

2018 ◽  
Vol 51 (4) ◽  
pp. 1982-1995 ◽  
Author(s):  
Yuji Kaneko ◽  
Julian P. Tuazon ◽  
Xunming Ji ◽  
Cesario V. Borlongan
Keyword(s):  
Cell Death ◽  
Adenylate Cyclase ◽  
Protein Expression ◽  
Cell Viability ◽  
Caspase 3 ◽  
High Mobility ◽  
High Mobility Group ◽  
Expression Levels ◽  
Pituitary Adenylate Cyclase ◽  
Nmdar Subunits

Background/Aims: The endogenous neurotrophic peptides pituitary adenylate cyclase-activating polypeptides (PACAP-27/38) protect against stroke, but the molecular mechanism remains unknown. Methods: Primary rat neural cells were exposed to PACAP-27 or PACAP-38 before induction of experimental acute ischemic stroke via oxygen-glucose deprivation-reperfusion (OGD/R) injury. To reveal PACAP’s role in neuroprotection, we employed fluorescent live/dead cell viability and caspase 3 assays, optical densitometry of mitochondrial dehydrogenase and cell growth, glutathione disulfide luciferase activity, ELISA for high mobility group box1 extracellular concentration, ATP bioluminescence, Western blot analysis of PACAP, NMDA subunits, apoptosis regulator Bcl-2, social interaction hormone oxytocin, and trophic factor BDNF, and immunocytochemical analysis of PACAP. Results: Both PACAP-27 and PACAP-38 (PACAP-27/38) increased cell viability, decreased oxidative stress-induced cell damage, maintained mitochondrial activity, prevented the release of high mobility group box1, and reduced cytochrome c/caspase 3-induced apoptosis. PACAP-27/38 increased the protein expression levels of BDNF, Bcl-2, oxytocin, and precursor PACAP. N-methyl-D-aspartate receptor (NMDAR)-induced excitotoxicity contributes to the cell death associated with stroke. PACAP-27/38 modulated the protein expression levels of NMDAR subunits. PACAP-27/38 increased the protein expression levels of the GluN1 subunit, and decreased that of the GluN2B and GluN2D subunits. PACAP-27, but not PACAP-38, increased the expression level of the GluN2C subunit. Conclusion: This study provides evidence that PACAP regulated NMDAR subunits, affording neuroprotection after OGD/R injury.

scholarly journals Effectiveness of Vitamin C and Vitamin E Antioxidant Combination on Caspase-3 Expression in Wistar White Rat Pulmonum Contusion

2020 ◽  
Vol 3 (1) ◽  
pp. 31-44
Author(s):  
Bermansyah ◽  
Gama Satria ◽  
Ahmad Umar
Keyword(s):  
Cell Death ◽  
Vitamin E ◽  
Vitamin C ◽  
Wistar Rats ◽  
Caspase 3 ◽  
Cell Function ◽  
Pulmonary Contusion ◽  
Tnf Α ◽  
Male Wistar Rats

Introduction.Pulmonary contusions can cause a progressive inflammatory response. Activation of TNF-α cytokines and reactive oxygen species (ROS) can cause pulmonary cell death. Antioxidants can have the potential to neutralize ROS. The purpose of this study is to determine the effectiveness of antioxidant administration in maintaining pulmonary cell function in wistar rats that have been induced to experience pulmonary contusions through caspase-3 levels. Methods.This study was an in vivo experimental study conducted on thirty male wistar rats and divided into five groups (n = 6): control, pulmonary contusion + asthaxanthine 5 mg/kgBW, pulmonary contusion + vitamin C and E 50 mg/kgBW, pulmonary contusion + vitamin C and E 100 mg/kgBW, pulmonary contusion + vitamin C and E 200 mg/kgBW. The value of Caspase-3 is evaluated by the IHC. All data analyzes used SPSS 18. Results. Low doses of antioxidants have the potential to reduce pulmonary cell death in wistar rats induced by pulmonary contusions.Conclussion. Vitamin C and E effective to reduce polmonary cell death in pulmonary contusion.Keywords: antioxidants, vitamin C, vitamin E, pulmonary contusions animal model, apoptosis, caspase-3

scholarly journals Anti-Apoptotic Effect of G-Protein-Coupled Receptor 40 Activation on Tumor Necrosis Factor-α-Induced Injury of Rat Proximal Tubular Cells

2019 ◽  
Vol 20 (14) ◽  
pp. 3386
Author(s):  
Chang Kim ◽  
Soo Joo ◽  
In Kim ◽  
Hoon-In Choi ◽  
Eun Bae ◽  
...  
Keyword(s):  
Protein Expression ◽  
Tumor Necrosis ◽  
Caspase 3 ◽  
Expression Ratio ◽  
Tnf Α ◽  
Apoptotic Effect ◽  
Proximal Tubular ◽  
Renal Tubular ◽  
G Protein Coupled ◽  
Necrosis Factor

G-protein-coupled receptor 40 (GPR40) has an anti-apoptotic effect in pancreatic β-cells. However, its role in renal tubular cell apoptosis remains unclear. To explore the role of GPR40 in renal tubular apoptosis, a two-week unilateral ureteral obstruction (UUO) mouse model was used. The protein expression of GPR40 was decreased, while the Bax/Bcl-2 protein expression ratio, the expression of tumor necrosis factor (TNF)-α mRNA, and angiotensin II type 1 receptor (AT1R) protein were increased in mice with UUO. In vitro, pretreatment of rat proximal tubular (NRK52E) cells with GW9508, a GPR40 agonist, attenuated the decreased cell viability, increased the Bax/Bcl-2 protein expression ratio, increased protein expression of cleaved caspase-3 and activated the nuclear translocation of nuclear factor-κB (NF-κB) p65 subunit induced by TNF-α treatment. TNF-α treatment significantly increased the expression of AT1R protein and the generation of reactive oxygen species (ROS), whereas GW9508 treatment markedly reversed these effects. Pretreatment with GW1100, a GPR40 antagonist, or silencing of GPR40 in NRK52E cells promoted the increased expression of the cleaved caspase-3 protein by TNF-α treatment. Our results demonstrate that decreased expression of GPR40 is associated with apoptosis via TNF-α and AT1R in the ureteral obstructed kidney. The activation of GPR40 attenuates TNF-α-induced apoptosis by inhibiting AT1R expression and ROS generation through regulation of the NF-κB signaling pathway.

scholarly journals Glibenclamide Reduces Inflammation, Vasogenic Edema, and Caspase-3 Activation after Subarachnoid Hemorrhage

2008 ◽  
Vol 29 (2) ◽  
pp. 317-330 ◽  
Author(s):  
J Marc Simard ◽  
Zhihua Geng ◽  
S Kyoon Woo ◽  
Svetlana Ivanova ◽  
Cigdem Tosun ◽  
...  
Keyword(s):  
Subarachnoid Hemorrhage ◽  
Caspase 3 ◽  
Cell Injury ◽  
Vasogenic Edema ◽  
Secondary Brain Injury ◽  
Sulfonylurea Receptor ◽  
Barrier Permeability ◽  
Markers Of Inflammation ◽  
Junction Protein

Subarachnoid hemorrhage (SAH) causes secondary brain injury due to vasospasm and inflammation. Here, we studied a rat model of mild-to-moderate SAH intended to minimize ischemia/hypoxia to examine the role of sulfonylurea receptor 1 (SUR1) in the inflammatory response induced by SAH. mRNA for Abcc8, which encodes SUR1, and SUR1 protein were abundantly upregulated in cortex adjacent to SAH, where tumor-necrosis factor-α (TNFα) and nuclear factor (NF)κB signaling were prominent. In vitro experiments confirmed that Abcc8 transcription is stimulated by TNFα. To investigate the functional consequences of SUR1 expression after SAH, we studied the effect of the potent, selective SUR1 inhibitor, glibenclamide. We examined barrier permeability (immunoglobulin G, IgG extravasation), and its correlate, the localization of the tight junction protein, zona occludens 1 (ZO-1). SAH caused a large increase in barrier permeability and disrupted the normal junctional localization of ZO-1, with glibenclamide significantly reducing both effects. In addition, SAH caused large increases in markers of inflammation, including TNFα and NFκB, and markers of cell injury or cell death, including IgG endocytosis and caspase-3 activation, with glibenclamide significantly reducing these effects. We conclude that block of SUR1 by glibenclamide may ameliorate several pathologic effects associated with inflammation that lead to cortical dysfunction after SAH.

scholarly journals Hyperglycemia Enhances DNA Fragmentation after Transient Cerebral Ischemia

2001 ◽  
Vol 21 (5) ◽  
pp. 568-576 ◽  
Author(s):  
Ping-An Li ◽  
Ingrid Rasquinha ◽  
Qing Ping He ◽  
Bo K. Siesjö ◽  
Katalin Csiszár ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Cell Death ◽  
Cytochrome C ◽  
Dna Fragmentation ◽  
Caspase 3 ◽  
Cingulate Cortex ◽  
Tunel Staining ◽  
Dna Fragments ◽  
Cytochrome C Release ◽  
Klenow Polymerase

Previous histopathologic results have suggested that one mechanism whereby hyperglycemia (HG) leads to exaggerated ischemic damage involves fragmentation of DNA. DNA fragmentation in normoglycemia (NG) and HG rats subjected to 30 minutes of forebrain ischemia was studied by terminal deoxynucleotidyl transferase mediated DNA nick-labeling (TUNEL) staining, by pulse-field gel electrophoresis (PFGE), and by ligation-mediated polymerase chain reaction (LM-PCR). High molecular weight DNA fragments were detected by PFGE, whereas low molecular weight DNA fragments were detected using LM-PCR techniques. The LM-PCR procedure was performed on DNA from test samples with blunt (without Klenow polymerase) and 3′-recessed ends (with Klenow polymerase). In addition, cytochrome c release and caspase-3 activation were studied by immunocytochemistry. Results show that HG causes cytochrome c release, activates caspase-3, and exacerbates DNA fragments induced by ischemia. Thus, in HG rats, but not in control or NGs, TUNEL-stained cells were found in the cingulate cortex, neocortex, thalamus, and dorsolateral crest of the striatum, where neuronal death was observed by conventional histopathology, and where both cytosolic cytochrome c and active caspase-3 were detected by confocal microscopy. In the neocortex, both blunt-ended and stagger-ended fragments were detected in HG, but not in NG rats. Electron microscopy (EM) analysis was performed in the cingulate cortex, where numerous TUNEL-positive neurons were observed. Although DNA fragmentation was detected by TUNEL staining and electrophoresis techniques, EM analysis failed to indicate apoptotic cell death. It is concluded that HG triggers a cell death pathway and exacerbates DNA fragmentation induced by ischemia.

scholarly journals Cobalt Protoporpyhrin Reduces Caspase-3,-7 Enzyme Activity in Neonatal Porcine Islets, But Does Not Inhibit Cell Death Induced by TNF-α

2008 ◽  
Vol 17 (6) ◽  
pp. 587-598 ◽  
Author(s):  
Erika Bosio ◽  
Michela Seveso ◽  
Arben Dedja ◽  
Giovanni Luca ◽  
Mario Calvitti ◽  
...  
Keyword(s):  
Cell Death ◽  
Enzyme Activity ◽  
Caspase 3 ◽  
Porcine Islets ◽  
Tnf Α ◽  
Neonatal Porcine Islets

scholarly journals The inducing of caspase and bcl-2 pathway with royal jelly decreases the muscle tissue damage exposed with fluoride in rats

2021 ◽  
Author(s):  
Abdullah Aslan ◽  
Muhammed Ismail Can ◽  
Ozlem Gok ◽  
Seda Beyaz ◽  
Gozde Parlak ◽  
...  
Keyword(s):  
Protein Expression ◽  
Muscle Tissue ◽  
Caspase 3 ◽  
Royal Jelly ◽  
Female Rats ◽  
Standard Diet ◽  
Expression Levels ◽  
Group Standard ◽  
Tnf Α ◽  
Caspase 6

Abstract In this study, 42 Wistar albino female rats (n = 42, 8 weeks old) were used. Rats were divided into 6 groups and 7 rats included each group. Groups: (i) Control Group: Standard diet; (ii) RJ (royal jelly) Group: Standard diet + royal jelly; (iii) F50 Group: Standard diet + 50 mg/kg fluoride; (iv): F100 Group: Standard diet + 100 mg/kg fluoride; (v) F50 + RJ Group: Standard diet + 50 mg/kg fluoride + royal jelly; (iv): F100 + RJ Group: Standard diet + 100 mg/kg fluoride + royal jelly. After the 8-week study period, the rats were decapitated and their muscle tissues were removed. Expression levels of Caspase-3, Caspase-6, Bax, Tnf-α, IL1-α and Bcl-2 proteins in muscle tissue were determined by Western Blotting method. Histopathological analyzes were also performed on the muscle tissue. MDA, GSH, and CAT analyzes were determined by spectrophotometric analysis. According to our findings, Bcl-2, Tnf-α and IL1-α protein expression were increased in damage groups compared to control and royal jelly groups, Caspase-3, Caspase-6 and Bax protein expression levels decreased in damage groups. There was an increase in MDA level in damage groups compared to the control and royal jelly groups, CAT and GSH levels decreased in damage groups. According to histopathological analysis results, edema and inflammatory cell formations were found in the injury groups, a tendency to decrease in these injuries was observed in the treatment groups. Based on these results, we can say that royal jelly has protective effects against fluoride damage.

scholarly journals Therapeutic effect of and mechanisms underlying the effect of miR-195-5p on subarachnoid hemorrhage-induced vasospasm and brain injury in rats

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11395
Author(s):  
Tai-Hsin Tsai ◽  
Chih-Hui Chang ◽  
Szu-Huai Lin ◽  
Yu-Feng Su ◽  
Yi-Cheng Tsai ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Cell Death ◽  
Subarachnoid Hemorrhage ◽  
Brain Injury ◽  
Nitric Oxide Synthase ◽  
Dentate Gyrus ◽  
Basilar Artery ◽  
Early Brain Injury ◽  
Cell Death Assay ◽  
Oxide Synthase

Objectives There is much evidence suggesting that inflammation contributes majorly to subarachnoid hemorrhage (SAH)-induced cerebral vasospasm and brain injury. miRNAs have been found to modulate inflammation in several neurological disorders. This study investigated the effect of miR-195-5p on SAH-induced vasospasm and early brain injury in experimental rats. Methods Ninety-six Sprague-Dawley male rats were randomly and evenly divided into a control group (no SAH, sham surgery), a SAH only group, a SAH + NC-mimic group, and a SAH + miR-195-5p group. SAH was induced using a single injection of blood into the cisterna magna. Suspensions containing NC-mimic and miR-195-5p were intravenously injected into rat tail 30 mins after SAH was induced. We determined degree of vasospasm by averaging areas of cross-sections the basilar artery 24h after SAH. We measured basilar artery endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κ B), phosphorylated NF-κ B (p-NF-κ B), inhibitor of NF-κ B (Iκ Bα) and phosphorylated-Iκ Bα (p-Iκ Bα). Cell death assay was used to quantify the DNA fragmentation, an indicator of apoptotic cell death, in the cortex, hippocampus, and dentate gyrus. Tumor necrosis factor alpha (TNF-α) levels were measured using sample protein obtained from the cerebral cortex, hippocampus and dentate gyrus. Results Prior to fixation by perfusion, there were no significant physiological differences among the control and treatment groups. SAH successfully induced vasospasm and early brain injury. MiR-195-5p attenuated vasospasam-induced changes in morphology, reversed SAH-induced elevation of iNOS, p-NF-κ B, NF-κ B, and p-Iκ Bα and reversed SAH-induced suppression of eNOS in the basilar artery. Cell death assay revealed that MiR-195-5p significantly decreased SAH-induced DNA fragmentation (apoptosis) and restored TNF-α level in the dentate gyrus. Conclusion In conclusion, MiRNA-195-5p attenuated SAH-induced vasospasm by up-regulating eNOS, down-regulating iNOS and inhibiting the NF-κ B signaling pathway. It also protected neurons by decreasing SAH-induced apoptosis-related cytokine TNF-α expression in the dentate gyrus. Further study is needed to elucidate the detail mechanism underlying miR-195-5p effect on SAH-induced vasospasm and cerebral injury. We believe that MiR-195-5p can potentially be used to manage SAH-induced cerebral vasospasm and brain injury.

Abstract 3877: The Magnitude and Temporal Dependence of Apoptosis Early After Myocardial Ischemia with or without Reperfusion

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Christopher French ◽  
A.K.M. Tarikuz Zaman ◽  
Jeffrey L Spees ◽  
Douglas J Taatjes ◽  
Burton E Sobel
Keyword(s):  
Cell Death ◽  
Caspase 3 ◽  
Apoptotic Cell ◽  
Supply And Demand ◽  
Coronary Artery Occlusion ◽  
Artery Occlusion ◽  
Ischemic Myocardium ◽  
Tunel Staining ◽  
Group Averaging ◽  
Myocardial Oxygen Supply

It has been hoped and conjectured that in addition to improving the balance between myocardial oxygen supply and demand amelioration of apoptosis could preserve jeopardized ischemic myocardium destined to undergo necrosis (cell death). Assessment of apoptosis in experimental animals has been based generally on TUNEL assays. Unfortunately, TUNEL positivity occurs with oncotic, mitotic, and autophagic, as well as apoptotic cell death. Accordingly, we characterized the extent of apoptosis after transient or persistent ischemia with highly specific methods. Coronary artery occlusion with and without subsequent revascularization was induced in three groups of 10 week old C57BL/6 mice: those subjected to 1 hr or 4 hr transient ligation followed by 24 hr of reperfusion (1HTLR24H, 4HTLR24H); or 24 hr persistent ligation (24HPL). Apoptosis was quantified throughout the LV by TUNEL, single stranded DNA (ssDNA), and caspase 3 immunohistochemistry, electron microscopy (EM), and caspase 3 and 8 activities assessed biochemically. TUNEL staining markedly exceeded and did not correlate with ssDNA, caspase 3 staining, or apoptosis defined by EM in any group. It was lowest in the 1HTLR24H group (averaging 38.6 of cells ± 3.1% [SEM], n = 9) greater in the 4HTLR24H group (48.5 ± 3.1%, n = 9), and significantly greater than both in the 24HPL group (67.2 ± 4.3%, n = 9, p < 0.01). ssDNA staining was minimal and similar in all three groups and significantly less than TUNEL staining (p < 0.01) (1HTLR24H, 1.0 ± 0.2%, n = 9; 4HTLR24H, 0.8 ± 0.1%, n = 9; 24HPL, 2.9 ± 1.6%, n = 9). Caspase 3 activity/mg protein (1HTLR24H, 15.3 ± 12, n = 3; 4HTLR24H, 58.5 ± 4, n = 3; 24HPL, 56.5 ± 10, n = 3) was similar to that in normal hearts (53.2 ± 11, n = 4), as was caspase 8 activity. No cleaved caspase 3 was seen immunohistochemically, and only rare, definitively identified apoptotic cells were seen by EM in hearts from any group. Apoptosis is de minimus early after transitory or persistent ischemia contrary to its overestimated, large extent as judged from TUNEL. Thus, antiapoptotic interventions per se are not likely to preserve substantial amounts of jeopardized ischemic myocardium early after ischemic insults.

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