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1.
ESC Heart Fail ; 7(6): 3329-3335, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33047896

ABSTRACT

AIMS: This study aims to report long-term mortality, echocardiographic, and clinical outcomes of patients receiving treatment for functional mitral regurgitation (FMR) with the Carillon device. METHODS AND RESULTS: This was a single centre analysis of prospectively collected data from patients treated with the Carillon Mitral Contour System for symptomatic congestive heart failure despite guideline-directed medical therapy, who were included from a single centre from the TITAN II study. All patients presented with New York Heart Association (NYHA) class 2 or greater symptoms, grade 2+ to 4+ FMR, left ventricular enlargement, and reduced ejection fraction. Surviving patients were evaluated for long-term follow-up post-procedure, averaging 6.9 years. Fifteen (15) patients (mean age 72 years, 60% male, 100% NYHA class III or IV, 50% MR grade 3+ or 4+) were treated with the Carillon device. The Kaplan-Meier mortality rate was 40% at 6 years of follow-up. Long-term survival through 6 years was associated with echocardiographic improvement in mitral regurgitation (change in effective regurgitant orifice area in survivors versus non-survivors from baseline to 1 year follow-up, -9.0 ± 5.6 vs. -1.7 ± 1.5, P = 0.02) and clinical status at 12 months (difference in NYHA at 1 year follow-up between survivors versus non-survivors, P = 0. 05) which was sustained throughout follow-up. All patients at 6 year follow-up had ≤2+ MR, with 6 of 7 having 0-1+ MR. Left ventricular end-diastolic volume was reduced from 154.0 ± 65.7 mL at baseline to 104.5 ± 59.2 mL at 6 year follow-up, P = 0.03 in survivors with both measurements. CONCLUSIONS: Among patients with congestive heart failure treated with the Carillon device, long-term survival is associated with favourable 1 year and sustained improvements in mitral regurgitation, left ventricular volume, ejection fraction, and clinical status.

2.
JACC Heart Fail ; 7(11): 945-955, 2019 11.
Article in English | MEDLINE | ID: mdl-31521683

ABSTRACT

OBJECTIVES: This study sought to evaluate the effects of the Carillon device on mitral regurgitation severity and left ventricular remodeling. BACKGROUND: Functional mitral regurgitation (FMR) complicates heart failure with reduced ejection fraction and is associated with a poor prognosis. METHODS: In this blinded, randomized, proof-of-concept, sham-controlled trial, 120 patients receiving optimal heart failure medical therapy were assigned to a coronary sinus-based mitral annular reduction approach for FMR or sham. The pre-specified primary endpoint was change in mitral regurgitant volume at 12 months, measured by quantitative echocardiography according to an intention-to-treat analysis. RESULTS: Patients (69.8 ± 9.5 years of age) were randomized to either the treatment (n = 87) or the sham-controlled (n = 33) arm. There were no significant differences in baseline characteristics between the groups. In the treatment group, 73 of 87 (84%) had the device implanted. The primary endpoint was met, with a statistically significant reduction in mitral regurgitant volume in the treatment group compared to the control group (decrease of 7.1 ml/beat [95% confidence interval [CI]: -11.7 to -2.5] vs. an increase of 3.3 ml/beat [95% CI: -6.0 to 12.6], respectively; p = 0.049). Additionally, there was a significant reduction in left ventricular volumes in patients receiving the device versus those in the control group (left ventricular end-diastolic volume decrease of 10.4 ml [95% CI: -18.5 to -2.4] vs. an increase of 6.5 ml [95% CI: -5.1 to 18.2]; p = 0.03 and left ventricular end-systolic volume decrease of 6.2 ml [95% CI: -12.8 to 0.4] vs. an increase of 6.1 ml [95% CI: -1.42 to 13.6]; p = 0.04). CONCLUSIONS: The Carillon device significantly reduced mitral regurgitant volume and left ventricular volumes in symptomatic patients with functional mitral regurgitation receiving optimal medical therapy. (Carillon Mitral Contour System for Reducing Functional Mitral Regurgitation [REDUCE FMR]; NCT02325830).


Subject(s)
Mitral Valve Annuloplasty/instrumentation , Mitral Valve Insufficiency/surgery , Aged , Double-Blind Method , Female , Humans , Male , Middle Aged , Mitral Valve Annuloplasty/methods , Proof of Concept Study , Severity of Illness Index , Ventricular Remodeling
3.
JACC Cardiovasc Interv ; 8(1 Pt A): 92-101, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25499305

ABSTRACT

OBJECTIVES: The purpose of this study was to evaluate the safety and efficacy of excimer laser atherectomy (ELA) with adjunctive percutaneous transluminal angioplasty (PTA) versus PTA alone for treating patients with chronic peripheral artery disease with femoropopliteal bare nitinol in-stent restenosis (ISR). BACKGROUND: Femoropopliteal stenting has shown superiority to PTA for lifestyle-limiting claudication and critical limb ischemia, although treating post-stenting artery reobstruction, or ISR, remains challenging. METHODS: The multicenter, prospective, randomized, controlled EXCITE ISR (EXCImer Laser Randomized Controlled Study for Treatment of FemoropopliTEal In-Stent Restenosis) trial was conducted across 40 U.S. centers. Patients with Rutherford Class 1 to 4 and lesions of target lesion length ≥4 cm, vessel diameter 5 to 7 mm were enrolled and randomly divided into ELA + PTA and PTA groups by a 2:1 ratio. The primary efficacy endpoint was target lesion revascularization (TLR) at 6-month follow up. The primary safety endpoint was major adverse event (death, amputation, or TLR) at 30 days post-procedure. RESULTS: Study enrollment was stopped at 250 patients due to early efficacy demonstrated at a prospectively-specified interim analysis. A total of 169 ELA + PTA subjects (62.7% male; mean age 68.5 ± 9.8 years) and 81 PTA patients (61.7% male; mean age 67.8 ± 10.3 years) were enrolled. Mean lesion length was 19.6 ± 12.0 cm versus 19.3 ± 11.9 cm, and 30.5% versus 36.8% of patients exhibited total occlusion. ELA + PTA subjects demonstrated superior procedural success (93.5% vs. 82.7%; p = 0.01) with significantly fewer procedural complications. ELA + PTA and PTA subject 6-month freedom from TLR was 73.5% versus 51.8% (p < 0.005), and 30-day major adverse event rates were 5.8% versus 20.5% (p < 0.001), respectively. ELA + PTA was associated with a 52% reduction in TLR (hazard ratio: 0.48; 95% confidence interval: 0.31 to 0.74). CONCLUSIONS: The EXCITE ISR trial is the first large, prospective, randomized study to demonstrate superiority of ELA + PTA versus PTA alone for treating femoropopliteal ISR. (Randomized Study of Laser and Balloon Angioplasty Versus Balloon Angioplasty to Treat Peripheral In-stent Restenosis [EXCITE ISR]; NCT01330628).


Subject(s)
Angioplasty, Balloon/adverse effects , Angioplasty, Balloon/instrumentation , Atherectomy/instrumentation , Femoral Artery/surgery , Laser Therapy/instrumentation , Lasers, Excimer/therapeutic use , Peripheral Arterial Disease/therapy , Popliteal Artery/surgery , Stents , Aged , Alloys , Amputation, Surgical , Angioplasty, Balloon/mortality , Atherectomy/adverse effects , Atherectomy/methods , Atherectomy/mortality , Chronic Disease , Combined Modality Therapy , Constriction, Pathologic , Female , Femoral Artery/physiopathology , Humans , Laser Therapy/adverse effects , Laser Therapy/methods , Laser Therapy/mortality , Lasers, Excimer/adverse effects , Limb Salvage , Male , Middle Aged , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/mortality , Peripheral Arterial Disease/surgery , Popliteal Artery/physiopathology , Prospective Studies , Prosthesis Design , Recurrence , Time Factors , Treatment Outcome , United States , Vascular Patency
4.
J Endovasc Ther ; 21(1): 52-60, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24502484

ABSTRACT

PURPOSE: To evaluate the performance of the Turbo Elite laser catheter in combination with the Turbo-Booster guiding catheter for the treatment of femoropopliteal in-stent restenosis (ISR). METHODS: The PATENT study (Photoablation Using the Turbo-Booster and Excimer Laser for In-Stent Restenosis Treatment) was a multicenter prospective industry-sponsored registry involving 5 European centers. Patients with symptomatic femoropopliteal ISR (Rutherford categories 2-5) and an ankle-brachial index ≤0.8 were treated with excimer laser atherectomy (ELA). Ninety patients (65 men; mean age 69.5±9.3 years) were enrolled. The majority of patients were Rutherford category 3 (63, 71.6%), and 32 (35.6%) patients had previous treatment for ISR. The average lesion length was 123±95.9 mm, and 30 (34.1%) lesions were total occlusions. The main efficacy outcome was primary patency at 12 months as measured by duplex ultrasonography. The primary safety outcome was freedom from major adverse events (MAE) during hospitalization and at 30-day follow-up to include all death, unplanned major amputation, or target lesion revascularization (TLR). RESULTS: The Turbo Elite laser catheter created a pilot channel in 87 (96.7%) of 90 lesions, with a mean of 1.5 passes, followed by the Turbo Booster with a mean of 5.7 passes. Adjunctive balloon dilation was performed in 79 (87.8%) lesions. Procedure success (<30% residual stenosis without stenting) was 96.7%. The mean percentage stenosis improved from a baseline of 87.0% to 32.3% after laser atherectomy and to 7.4% after final treatment. The MAE rate through 30 days was 2.2%. Nine (10.0%) patients experienced distal embolization. Estimates of freedom from TLR at 6 and 12 months were 87.8% and 64.4%, respectively. Primary patency at 6 and 12 months was 64.1% and 37.8%, respectively. Only a history of prior intervention for ISR (p<0.01) was a predictor of TLR at 12 months. CONCLUSION: The PATENT study has established excimer laser atherectomy as safe for the treatment of femoropopliteal ISR, achieving high procedure success. Recurrence of restenosis indicates that removing hyperproliferative tissue alone does not solve the problem of ISR. New concepts, such as the combination of ELA with drug-eluting balloons, may prove beneficial.


Subject(s)
Endovascular Procedures/instrumentation , Femoral Artery/surgery , Laser Therapy/instrumentation , Lasers, Excimer , Peripheral Arterial Disease/therapy , Popliteal Artery/surgery , Stents , Aged , Amputation, Surgical , Ankle Brachial Index , Constriction, Pathologic , Endovascular Procedures/adverse effects , Equipment Design , Female , Femoral Artery/diagnostic imaging , Humans , Laser Therapy/adverse effects , Limb Salvage , Male , Middle Aged , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/surgery , Popliteal Artery/diagnostic imaging , Prospective Studies , Recurrence , Registries , Reoperation , Risk Factors , Time Factors , Treatment Outcome , Ultrasonography, Doppler, Duplex
5.
J Immunol ; 183(9): 5685-93, 2009 Nov 01.
Article in English | MEDLINE | ID: mdl-19843951

ABSTRACT

IL-17A and IL-17F regulate granulopoiesis and are produced by memory T cells. Rag1(-/-) recombinase-activating gene-deficient mice cannot produce mature T cells but maintain normal neutrophil counts. Athymic nude mice are neutropenic or have near-normal neutrophil counts, depending on the prevailing intestinal flora, and do not produce IL-17A. By contrast, thymi from Rag1(-/-) mice contain as much IL-17A as those from wild-type (WT) mice. IL-17A-producing cells are found in the double negative DN1 compartment of the Rag1(-/-) thymus and express intracellular CD3. These cells colonize the spleen and mesenteric lymph node and secrete IL-17A in vitro following stimulation with IL-23 at a level similar to that of WT splenocytes. Adoptively transferred Rag1(-/-) or WT thymocytes correct neutrophil counts in neutropenic nude mice. We conclude that the development of IL-17A-producing T-lineage cells requires an intact thymic epithelium, but not V(D)J recombination.


Subject(s)
Gene Rearrangement, T-Lymphocyte , Interleukin-17/biosynthesis , Neutrophils/immunology , Neutrophils/metabolism , Receptors, Antigen, T-Cell/genetics , T-Lymphocyte Subsets/immunology , Thymus Gland/cytology , Thymus Gland/immunology , Animals , Antibody Diversity/genetics , Cell Lineage/genetics , Cell Lineage/immunology , Epithelium/immunology , Epithelium/metabolism , Gene Rearrangement, T-Lymphocyte/immunology , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Heavy Chains/metabolism , Immunoglobulin Joining Region/genetics , Immunoglobulin Joining Region/metabolism , Immunoglobulin Variable Region/genetics , Immunoglobulin Variable Region/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Nude , Mice, Transgenic , Neutropenia/genetics , Neutropenia/immunology , Neutropenia/metabolism , Neutrophils/pathology , Receptors, Antigen, T-Cell/metabolism , T-Lymphocyte Subsets/metabolism , T-Lymphocyte Subsets/transplantation , Thymus Gland/metabolism
6.
J Immunol ; 181(2): 1357-64, 2008 Jul 15.
Article in English | MEDLINE | ID: mdl-18606690

ABSTRACT

IL-23 and IL-17A regulate granulopoiesis through G-CSF, the main granulopoietic cytokine. IL-23 is secreted by activated macrophages and dendritic cells and promotes the expansion of three subsets of IL-17A-expressing neutrophil-regulatory T (Tn) cells; CD4(-)CD8(-)alphabeta(low), CD4(+)CD8(-)alphabeta(+) (Th17), and gammadelta(+) T cells. In this study, we investigate the effects of IL-17A on circulating neutrophil levels using IL-17R-deficient (Il17ra(-/-)) mice and Il17ra(-/-)Itgb2(-/-) mice that lack both IL-17R and all four beta(2) integrins. IL-17R deficiency conferred a reduction in neutrophil numbers and G-CSF levels, as did Ab blockade against IL-17A in wild-type mice. Bone marrow transplantation revealed that IL-17R expression on nonhemopoietic cells had the greatest effects on regulating blood neutrophil counts. Although circulating neutrophil numbers were reduced, IL-17A expression, secretion, and the number of IL-17A-producing Tn cells were elevated in Il17ra(-/-) and Il17ra(-/-)Itgb2(-/-) mice, suggesting a negative feedback effect through IL-17R. The negative regulation of IL-17A-producing T cells and IL-17A and IL-17F gene expression through the interactions of IL-17A or IL-17F with IL-17R was confirmed in splenocyte cultures in vitro. We conclude that IL-17A regulates blood neutrophil counts by inducing G-CSF production mainly in nonhemopoietic cells. IL-17A controls the expansion of IL-17A-producing Tn cell populations through IL-17R.


Subject(s)
Granulocyte Colony-Stimulating Factor/metabolism , Interleukin-17/metabolism , Interleukin-23/metabolism , Neutrophils/physiology , Receptors, Interleukin-17/metabolism , T-Lymphocyte Subsets/immunology , Animals , Cell Polarity , Dendritic Cells/immunology , Dendritic Cells/metabolism , Granulocyte Colony-Stimulating Factor/immunology , Interleukin-17/immunology , Interleukin-23/immunology , Leukocyte Count , Macrophages/immunology , Macrophages/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Neutrophils/immunology , Receptors, Interleukin-17/deficiency , Receptors, Interleukin-17/immunology , T-Lymphocyte Subsets/cytology , T-Lymphocyte Subsets/metabolism
7.
J Immunol ; 179(12): 8274-9, 2007 Dec 15.
Article in English | MEDLINE | ID: mdl-18056371

ABSTRACT

IL-23 is secreted by macrophages and dendritic cells in response to microbial products and inflammatory cytokines. IL-23 is a heterodimer composed of the unique IL-23p19 subunit linked to the common p40 subunit that it shares with IL-12. IL-23 is implicated in autoimmune diseases, where it supports the expansion of IL-17A-producing CD4+ Th17 cells. IL-23 also regulates granulopoiesis in a neutrostat regulatory feedback loop through IL-17A-producing neutrophil regulatory (Tn) cells, most of which express gammadelta TCR. This homeostatic system is disrupted in mice lacking adhesion molecules like beta2-integrins (Itgb2-/-) which have defective neutrophil trafficking and neutrophilia. To test the role of IL-23 in the homeostatic regulation of circulating neutrophil numbers, we measured blood neutrophil numbers in p40-deficient (IL12b-/-) mice and found them reduced compared with wild-type mice. IL12b-/-Itgb2-/- mice, lacking beta2-integrins, IL-12, and IL-23 showed significantly blunted neutrophilia compared with Itgb2-/- mice. Treatment of both IL12b-/- and IL12b-/-Itgb2-/- mice with IL-23, but not IL-12, restored circulating neutrophil counts. Serum levels of IL-17A were readily detectable in Itgb2-/- mice, but not in IL12b-/-Itgb2-/- mice, suggesting that IL-17A production is reduced when IL-23 is absent. Similarly, tissue mRNA expression of IL-17A was reduced in IL12b-/-Itgb2-/-mice compared with Itgb2-/- controls. The total number of CD3+ IL-17A-producing Tn cells were significantly reduced in the spleen and lamina propria of IL12b-/-Itgb2-/- mice, with the largest reduction found in gammadelta+ T cells. Our results suggest a prominent role of IL-23 in the regulation of granulopoiesis and the prevalence of IL-17A-producing Tn cells.


Subject(s)
Interleukin-12 Subunit p40/physiology , Interleukin-23/physiology , Neutropenia/genetics , Neutrophils/immunology , Animals , CD18 Antigens/genetics , Homeostasis/immunology , Interleukin-12 Subunit p40/genetics , Interleukin-17/blood , Interleukin-17/genetics , Interleukin-17/metabolism , Interleukin-23/genetics , Mice , Mice, Mutant Strains
8.
Immunol Res ; 34(3): 229-42, 2006.
Article in English | MEDLINE | ID: mdl-16891673

ABSTRACT

The proinflammatory cytokine IL-17A, mainly produced by specialized T cells, plays an important homeostatic role in regulating neutrophil production and blood neutrophil counts. This review will assemble and discuss the evidence for this function of IL-17A-producing cells, which are collectively called neutrophil-regulatory T cells or Tn cells. IL-17A-producing lymphocytes are most abundant in the mesenteric lymph node, where they account for 0.15% of all lymphocytes. About 60% of the Tn cells are gammadelta T cells, about 25% NKTlike cells, and less than 15% are CD4 T cells. These latter cells are also known as T-17 or ThIL-17 cells, a subset of Tn cells that also plays an important role in autoimmune diseases. IL-17A produced by Tn cells regulates the production of G-CSF, which in turn promotes the proliferation of promyelocytes and maturation of neutrophils. This homeostatic mechanism plays an important role in normal physiology and in host defense against bacterial infections. This review is aimed at highlighting the important role of IL-17A-producing T cells at the interface between the adaptive and innate immune system.


Subject(s)
Interleukin-17/immunology , Neutrophils/immunology , T-Lymphocytes, Regulatory/immunology , Animals , Apoptosis/immunology , Apoptosis/physiology , Granulocyte Colony-Stimulating Factor/immunology , Humans , Interleukin-17/biosynthesis , Interleukin-23 , Interleukin-23 Subunit p19 , Interleukins/immunology , Mice , Models, Molecular , Phagocytes/immunology , Receptors, Interleukin/biosynthesis , Receptors, Interleukin/immunology
9.
Immunity ; 22(3): 285-94, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15780986

ABSTRACT

Homeostatic regulation of neutrophil production is thought to match neutrophil elimination to maintain approximately constant numbers in the blood. Here, we show that IL-17, a cytokine that regulates granulopoiesis through G-CSF, is made by gammadelta T cells and unconventional alphabeta T cells. These neutrophil-regulatory T cells (Tn) are expanded in mice that lack leukocyte adhesion molecules, which have neutrophilia and defective neutrophil trafficking. Normal neutrophils migrate to tissues, where they become apoptotic and are phagocytosed by macrophages and dendritic cells. This curbs phagocyte secretion of IL-23, a cytokine controlling IL-17 production by Tn cells. Adoptive transfer of wild-type, but not adhesion molecule-deficient, neutrophils into mice deficient in beta2 integrins transiently decreases neutrophilia and reduces levels of serum IL-17. Antibody blockade of the p40 subunit of IL-23 reduces neutrophil numbers in wild-type mice. These findings identify a major homeostatic mechanism for the regulation of neutrophil production in vivo.


Subject(s)
Apoptosis/immunology , Granulocytes/immunology , Interleukin-17/immunology , Interleukins/immunology , Neutrophils/immunology , Phagocytosis/immunology , Adoptive Transfer , Animals , Bone Marrow/immunology , CD18 Antigens/immunology , CD18 Antigens/metabolism , Cell Adhesion Molecules/deficiency , Cell Transplantation , Chemotaxis, Leukocyte/immunology , Dendritic Cells/immunology , Interleukin-17/metabolism , Interleukin-23 , Interleukin-23 Subunit p19 , Interleukins/metabolism , Macrophages/immunology , Mice , Mice, Knockout , Neutrophils/metabolism , Neutrophils/pathology , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction , T-Lymphocytes/immunology , T-Lymphocytes/metabolism
10.
Circulation ; 110(14): 2024-31, 2004 Oct 05.
Article in English | MEDLINE | ID: mdl-15451785

ABSTRACT

BACKGROUND: Mice lacking leukocyte type 12/15-lipoxygenase (12/15-LO) show reduced atherosclerosis in several models. 12/15-LO is expressed in a variety of cells, including vascular cells, adipocytes, macrophages, and cardiomyocytes. The purpose of this study was to determine which cellular source of 12/15-LO is important for atherosclerosis. METHODS AND RESULTS: Bone marrow from 12/15-LO-/-/apoE-/- mice was transplanted into apoE-/- mice and vice versa. Deficiency of 12/15-LO in bone marrow cells protected apoE-/- mice fed a Western diet from atherosclerosis to the same extent as complete absence of 12/15-LO, although plasma 8,12-iso-iPF2alpha-IV, a measure of lipid peroxidation, remained elevated. 12/15-LO-/-/apoE-/- mice regained the severity of atherosclerotic lesion typical of apoE-/- mice after replacement of their bone marrow cells with bone marrow from apoE-/- mice. Peritoneal macrophages obtained from wild-type but not 12/15-LO-/- mice caused endothelial activation in the presence of native LDL. Absence of 12/15-LO decreased the ability of macrophages to form foam cells when exposed to LDL. CONCLUSIONS: We conclude that macrophage 12/15-LO plays a dominant role in the development of atherosclerosis by promoting endothelial inflammation and foam cell formation.


Subject(s)
Apolipoproteins E/deficiency , Arachidonate 12-Lipoxygenase/physiology , Arachidonate 15-Lipoxygenase/physiology , Arteriosclerosis/enzymology , Dinoprost/analogs & derivatives , Endothelial Cells/enzymology , Foam Cells/cytology , Hyperlipoproteinemia Type II/enzymology , Macrophages, Peritoneal/enzymology , Myocytes, Smooth Muscle/enzymology , Animals , Apolipoproteins E/genetics , Arachidonate 12-Lipoxygenase/deficiency , Arachidonate 12-Lipoxygenase/genetics , Arachidonate 15-Lipoxygenase/deficiency , Arachidonate 15-Lipoxygenase/genetics , Autocrine Communication , Bone Marrow Transplantation , Cell Adhesion/drug effects , Cell Differentiation/drug effects , Cells, Cultured/cytology , Cells, Cultured/drug effects , Cells, Cultured/enzymology , Dinoprost/blood , Endothelial Cells/drug effects , Endothelium, Vascular/cytology , Hyperlipoproteinemia Type II/blood , Hyperlipoproteinemia Type II/genetics , Interleukin-4/pharmacology , Lipoproteins, LDL/pharmacology , Macrophages, Peritoneal/cytology , Macrophages, Peritoneal/drug effects , Mice , Mice, Knockout , Muscle, Smooth, Vascular/cytology , Myocytes, Smooth Muscle/cytology , Myocytes, Smooth Muscle/drug effects , RNA, Messenger/biosynthesis , Radiation Chimera , Triglycerides/blood
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