scholarly journals Increased Serum Complement C3 Levels Are Associated With Adverse Clinical Outcomes After Ischemic Stroke

Stroke ◽  
2021 ◽  
Author(s):  
Pinni Yang ◽  
Zhengbao Zhu ◽  
Yuhan Zang ◽  
Xiaoqing Bu ◽  
Tian Xu ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Clinical Outcomes ◽  
Primary Outcome ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Elevated Serum ◽  
Complement C3 ◽  
Serum Complement ◽  
Vascular Events ◽  
Increased Risk

Background and Purpose: Complement C3 has been implicated in inflammation and ischemia/reperfusion injury, but its impact on the prognosis of ischemic stroke remains unclear. Aim of this study was to prospectively investigate the association between serum complement C3 and adverse clinical outcomes after ischemic stroke. Methods: We measured serum complement C3 levels for 3474 patients with ischemic stroke in 26 participating hospitals and collected data of clinical outcomes at 3 months after ischemic stroke. The primary outcome was composite outcome of death and major disability (modified Rankin Scale score ≥3) at 3 months after stroke onset and secondary outcomes included major disability, death, and vascular events. Results: During 3 months of follow-up, 866 participants (25.4%) developed primary outcome. After multivariate adjustment, elevated serum complement C3 levels were associated with increased risk of primary outcome (odds ratio, 1.30 [95% CI, 1.02–1.65]; P trend =0.038) when 2 extreme tertiles were compared. Each SD increase of log-transformed complement C3 was associated with 13% (95% CI, 2%–25%) increased risk of primary outcome. Multivariable-adjusted spline regression model showed a linear relationship between serum complement C3 and the risk of primary outcome ( P linearity =0.022). Addition of serum complement C3 to conventional risk factors significantly improved the risk prediction of primary outcome (net reclassification index: 8.87%, P =0.028; integrated discrimination index: 0.19%, P =0.029). Conclusions: High serum complement C3 levels at baseline were associated with increased risks of adverse clinical outcomes at 3 months after ischemic stroke, suggesting that serum complement C3 may be a valuable prognostic biomarker for ischemic stroke.

Multiple biomarkers covering distinct pathways for predicting outcomes after ischemic stroke

Neurology ◽  
2018 ◽  
Vol 92 (4) ◽  
pp. e295-e304 ◽  
Author(s):  
Chongke Zhong ◽  
Zhengbao Zhu ◽  
Aili Wang ◽  
Tan Xu ◽  
Xiaoqing Bu ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Primary Outcome ◽  
Prognostic Significance ◽  
Complement C3 ◽  
Vascular Events ◽  
Net Reclassification Improvement ◽  
Increased Risk ◽  
Multiple Biomarkers ◽  
Novel Biomarkers ◽  
Integrated Discrimination Improvement

ObjectiveTo study the prognostic significance of multiple novel biomarkers in combination after ischemic stroke.MethodsWe derived data from the China Antihypertensive Trial in Acute Ischemic Stroke, and 12 informative biomarkers were measured. The primary outcome was the combination of death and major disability (modified Rankin Scale score ≥3) at 3 months after ischemic stroke, and secondary outcomes included major disability, death, and vascular events.ResultsIn 3,405 participants, 866 participants (25.4%) experienced major disability or died within 3 months. In multivariable analyses, elevated high-sensitive C-reactive protein, complement C3, matrix metalloproteinase-9, hepatocyte growth factor, and antiphosphatidylserine antibodies were individually associated with the primary outcome. Participants with a larger number of elevated biomarkers had increased risk of all study outcomes. The adjusted odds ratios (95% confidence intervals) of participants with 5 elevated biomarkers were 3.88 (2.05–7.36) for the primary outcome, 2.81 (1.49–5.33) for major disability, 5.67 (1.09–29.52) for death, and 4.00 (1.22–13.14) for vascular events, compared to those with no elevated biomarkers. Simultaneously adding these 5 biomarkers to the basic model with traditional risk factors led to substantial reclassification for the combined outcome (net reclassification improvement 28.5%, p < 0.001; integrated discrimination improvement 2.2%, p < 0.001) and vascular events (net reclassification improvement 37.0%, p = 0.001; integrated discrimination improvement 0.8%, p = 0.001).ConclusionWe observed a clear gradient relationship between the numbers of elevated novel biomarkers and risk of major disability, mortality, and vascular events. Incorporation of a combination of multiple biomarkers observed substantially improved the risk stratification for adverse outcomes in ischemic stroke patients.

Tissue inhibitor metalloproteinase-1 and clinical outcomes after acute ischemic stroke

Neurology ◽  
2019 ◽  
Vol 93 (18) ◽  
pp. e1675-e1685 ◽  
Author(s):  
Chongke Zhong ◽  
Guangli Wang ◽  
Tan Xu ◽  
Zhengbao Zhu ◽  
Daoxia Guo ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Clinical Outcomes ◽  
Scale Score ◽  
Primary Outcome ◽  
Tissue Inhibitor ◽  
Vascular Events ◽  
Baseline Serum ◽  
Hazard Ratios ◽  
Increased Risk

ObjectiveTo prospectively investigate the relationships between serum tissue inhibitor metalloproteinase-1 (TIMP-1) and clinical outcomes in patients with acute ischemic stroke.MethodsWe derived data from the China Antihypertensive Trial in Acute Ischemic Stroke. Baseline serum TIMP-1 concentrations were measured in 3,342 participants. The primary outcome was the combination of death and major disability (modified Rankin Scale score ≥3) at 3 months after ischemic stroke, and secondary outcomes included major disability, death, and vascular events.ResultsA total of 843 participants (25.2%) experienced major disability or died within 3 months. After adjustment for age, sex, admission NIH Stroke Scale score, and other important covariates, odds ratios or hazard ratios (95% confidence intervals) of 1-SD (0.17 ng/mL) higher log-TIMP-1 were 1.17 (1.06–1.29) for the primary outcome, 1.13 (1.02–1.25) for major disability, 1.49 (1.19–1.87) for death, and 1.34 (1.11–1.62) for the composite outcome of death and vascular events. The addition of serum TIMP-1 to conventional risk factors model significantly improved risk prediction of the primary outcome (net reclassification index 9.0%, p = 0.02; integrated discrimination improvement 0.2%, p = 0.03). Participants with both higher TIMP-1 and matrix metalloproteinase-9 levels simultaneously had the highest risk of all study outcomes.ConclusionsHigher TIMP-1 levels were associated with increased risk of mortality and major disability after acute ischemic stroke. Our findings provided evidence supporting the important prognostic role of extracellular matrix biomarkers after acute ischemic stroke.

scholarly journals Plasma S100A8/A9 Concentrations and Clinical Outcomes of Ischemic Stroke in 2 Independent Multicenter Cohorts

2020 ◽  
Vol 66 (5) ◽  
pp. 706-717
Author(s):  
Daoxia Guo ◽  
Zhengbao Zhu ◽  
Tan Xu ◽  
Chongke Zhong ◽  
Aili Wang ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Clinical Outcomes ◽  
Primary Outcome ◽  
High Plasma ◽  
Secondary Outcome ◽  
Composite Outcome ◽  
Vascular Events ◽  
Hazard Ratios ◽  
Increased Risk

Abstract Background S100A8/A9 is implicated in inflammation mechanisms related to atherosclerosis and plaque vulnerability, but it remains unclear whether S100A8/A9 is associated with the prognosis of ischemic stroke. The aim of this study was to investigate these associations in 2 independent multicenter cohorts. Methods Plasma S100A8/A9 concentrations at baseline were measured among 4785 patients with ischemic stroke from 2 independent cohorts: Infectious Factors, Inflammatory Markers, and Prognosis of Acute Ischemic Stroke (IIPAIS) and China Antihypertensive Trial in Acute Ischemic Stroke (CATIS). The primary outcome was a composite outcome of death or major disability at 3 months after ischemic stroke. Secondary outcomes were major disability, death, and a composite outcome of death or vascular events. Results Among the combined participants of IIPAIS and CATIS, the adjusted odds ratios associated with the highest quartile of plasma S100A8/A9 were 2.11 (95% CI, 1.66–2.68) for the primary outcome and 1.62 (95% CI, 1.27–2.07) for the secondary outcome of major disability; adjusted hazard ratios were 4.14 (95% CI, 2.10–8.15) for the secondary outcome of death and 2.08 (95% CI, 1.38–3.13) for the composite outcome of death or vascular events. Each SD increase of log-transformed S100A8/A9 was associated with 28% (95% CI, 18%–39%; P &lt; 0.001) increased risk of the primary outcome. Multivariable-adjusted spline regression analyses showed a linear association between plasma S100A8/A9 concentrations and primary outcome (P &lt; 0.001 for linearity). Subgroup analyses further confirmed these associations. Conclusions High plasma S100A8/A9 concentrations at baseline were independently associated with increased risks of adverse clinical outcomes at 3 months after ischemic stroke, suggesting that S100A8/A9 might have a role as a prognostic marker of ischemic stroke.

scholarly journals Increased Growth Differentiation Factor 15 Is Associated with Unfavorable Clinical Outcomes of Acute Ischemic Stroke

2019 ◽  
Vol 65 (4) ◽  
pp. 569-578 ◽  
Author(s):  
Jieyun Yin ◽  
Zhengbao Zhu ◽  
Daoxia Guo ◽  
Aili Wang ◽  
Nimei Zeng ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Clinical Outcomes ◽  
Primary Outcome ◽  
Stroke Recurrence ◽  
Stroke Patients ◽  
Vascular Events ◽  
Baseline Serum ◽  
Growth Differentiation Factor 15 ◽  
Differentiation Factor

Abstract BACKGROUND Growth differentiation factor 15 (GDF-15), a stress-responsive biomarker, is known to be independently associated with mortality and cardiovascular events in different disease settings, but data on the prognostic value of GDF-15 after stroke are limited. METHODS Baseline serum GDF-15 was measured in 3066 acute ischemic stroke patients from the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS). The primary outcome was a composite of death and major disability within 3 months. Secondary outcomes included death, major disability, vascular events, and stroke recurrence. The associations between GDF-15 and clinical outcomes after stroke were assessed by multivariate logistic regression or Cox proportional hazards models. RESULTS At 3 months' follow-up, 676 (22.05%), 86 (2.80%), 81 (2.64%), and 51 (1.66%) patients had experienced major disability, death, vascular events, or stroke recurrence, respectively. After adjusting for age, sex, current smoking, alcohol consumption, and baseline National Institutes of Health Stroke Scale score, the odds ratio/hazard ratio (95% CI) of 1 SD higher of base-10 log-transformed GDF-15 was 1.26 (1.15–1.39) for primary outcome, 1.13 (1.02–1.25) for major disability, 1.79 (1.48–2.16) for death, and 1.26 (1.00–1.58) for vascular events. The addition of GDF-15 to established risk factors improved risk prediction of the composite outcome of death and major disability (c-statistic, net reclassification index, and integrated discrimination improvement, all P &lt; 0.05). CONCLUSIONS High GDF-15 concentrations are independently associated with adverse clinical outcomes of acute ischemic stroke, suggesting that baseline serum GDF-15 could provide additional information to identify ischemic stroke patients at high risk of poor prognosis.

scholarly journals ADAMTS13, an Anti-thrombotic Protein: Evidence Outside of Thrombotic Thrombocytopenic Purpura

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. SCI-41-SCI-41
Author(s):  
Simon De Meyer
Keyword(s):  
Endothelial Cells ◽  
Ischemic Stroke ◽  
Thrombotic Thrombocytopenic Purpura ◽  
Research Funding ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Von Willebrand Disease ◽  
Thrombocytopenic Purpura ◽  
Increased Risk ◽  
Von Willebrand

von Willebrand factor (VWF) is a large multimeric plasma glycoprotein that plays a crucial role in hemostasis and thrombosis. VWF recruits platelets at sites of vascular injury by acting as a molecular bridge between circulating platelets and the site of injured or activated blood vessels. Biosynthesis of VWF is restricted to endothelial cells and megakaryocytes. Endothelial VWF is constitutively secreted into plasma and subendothelium, or is stored as "ultra-large" (UL)-VWF multimers in endothelial Weibel-Palade bodies. VWF produced in megakaryocytes is packaged as UL-VWF in the a-granules of platelets. VWF stored in endothelial and platelet storage organelles is secreted in a regulated process in response to stimulation by secretagogues. Absence or dysfunction of VWF results in bleeding symptoms, as observed in patients with von Willebrand disease. An abnormally high activity of VWF can lead to thrombotic events. Interestingly, the activity of VWF is determined by the size of its multimers and UL-VWF can spontaneously form platelet aggregates. An important regulator of VWF size is the metalloprotease ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13), which digests large thrombogenic VWF molecules into smaller, less reactive multimers via cleavage of the Y1605-M1606 bond in the VWF A2 domain. ADAMTS13 is mainly synthesized in the liver by hepatic stellate cells, but other sites of synthesis, including renal podocytes, tubular epithelial cell, platelets and endothelial cells, have also been described. ADAMTS13 is released as an active enzyme into the circulation with no physiological inhibitors. Reduced or absent ADAMTS13 activity causes the microangiopathic disorder thrombotic thrombocytopenic purpura (TTP), characterized by VWF and platelet-rich microthrombi that cause multiple organ failure and even death when left untreated. Besides its clear role in the pathophysiology of TTP, the anti-thrombotic and even anti-inflammatory properties of ADAMTS13 have also become apparent in various other thrombotic conditions. High VWF levels and low ADAMTS13 levels are associated with increased risk or even worse outcome of cardiovascular disease, including ischemic stroke and myocardial infarction. Preclinical studies in mouse models showed the beneficial effect of ADAMTS13 in both cerebral and myocardial ischemia/ reperfusion injury by decreasing both thrombosis and inflammation. In addition, ADAMTS13 was shown to also exert a direct thrombolytic effect on VWF-rich thrombi. In a mouse model of ischemic stroke, this thrombolytic activity resulted in efficient lysis of intracranial thrombi that were resistant to standard treatment with tissue plasminogen activator. Hence, ADAMTS13, as a therapeutic agent, could become an interesting avenue, not only to manage TTP, but also to treat other thrombotic complications. Disclosures De Meyer: Fonds voor Wetenschappelijk Onderzoek: Research Funding; KU Leuven: Employment, Research Funding; Ablynx: Consultancy, Research Funding; Cerenovus: Membership on an entity's Board of Directors or advisory committees; WhiteSwell: Consultancy.

scholarly journals 270. Clinical Outcomes of Ceftriaxone versus Penicillin G for Complicated Viridans Group Streptococci Bacteremia

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S137-S137
Author(s):  
Stephanie Wo ◽  
Yanina Dubrovskaya ◽  
Justin Siegfried ◽  
John Papadopoulos ◽  
Shin-Pung Jen
Keyword(s):  
Clinical Outcomes ◽  
Hospital Readmission ◽  
Protective Factor ◽  
Primary Outcome ◽  
Bloodstream Infections ◽  
Penicillin G ◽  
Eligibility Criteria ◽  
Extended Spectrum Beta Lactamase ◽  
Increased Risk ◽  
Viridans Group Streptococci

Abstract Background Viridans group streptococci (VGS) is an infrequent yet significant cause of bloodstream infections, and complicated cases may require prolonged antibiotic therapy. Ceftriaxone (CTX) and penicillin G (PCN G) are both considered first line options for VGS infections, but comparisons between these agents are limited. We evaluated the clinical outcomes amongst patients treated with CTX and PCN G for complicated VGS bacteremia. Methods This was a single-center, retrospective study of adult patients with ≥1 positive VGS blood culture who were treated with either CTX or PCN G/ampicillin (both included in PCN G arm) between January 2013 and June 2019. The primary outcome was a composite of safety endpoints, including hospital readmission due to VGS or an adverse event (AE) from therapy, Clostridioides difficile infections, treatment modification or discontinuation due to an antibiotic-related AE, and development of extended-spectrum beta lactamase resistance. Secondary outcomes included the individual safety endpoints, VGS bacteremia recurrence, hospital readmission, and all-cause mortality. Results Of 328 patients screened for inclusion, 94 patients met eligibility criteria (CTX n= 64, PCN G n=34). Median age was 68 years (IQR 56–81) and 68% were male. Study patients did not present with critical illness, as reflected by a median Pitt bacteremia score of 0 in the CTX and 1 in the PCN G arms, P=0.764. Streptococcus mitis was the most common VGS isolate and infective endocarditis (IE) was the predominant source of infection. CTX was not significantly associated with increased risk of the primary outcome (14% vs. 27%; P= 0.139). The driver of the composite outcome was hospital readmission due to VGS bacteremia or therapy complications. Results were similar in the subgroup of patients with IE (12.5% vs. 23.5%). No secondary endpoints differed significantly between groups. On multivariate analysis, source removal was a protective factor of the primary outcome (OR 0.1; 95% CI 0.020–0.6771; P= 0.017). Conclusion Despite potential safety concerns with the prolonged use of CTX in complicated VGS bacteremia, this study did not demonstrate a higher rate of treatment failure, adverse events, or resistance. These findings warrant further exploration. Disclosures All Authors: No reported disclosures

Non-contrast head CT alone for thrombectomy in acute ischemic stroke: analysis of the ANGEL-ACT registry

2021 ◽  
pp. neurintsurg-2021-017940
Author(s):  
Zeguang Ren ◽  
Gaoting Ma ◽  
Maxim Mokin ◽  
Ashutosh P Jadhav ◽  
Baixue Jia ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Clinical Outcomes ◽  
Primary Outcome ◽  
Ct Perfusion ◽  
Non Invasive ◽  
Vessel Imaging ◽  
Baseline Characteristics ◽  
Procedural Outcomes ◽  
Head Computed Tomography

BackgroudThe goal of this study was to determine if the choice of imaging paradigm performed in the emergency department influences the procedural or clinical outcomes after mechanical thrombectomy (MT).MethodsThis is a retrospective comparative outcome study which was conducted from the ANGEL-ACT registry. Comparisons were made between baseline characteristics and clinical outcomes of patients with acute ischemic stroke undergoing MT with non-contrast head computed tomography (NCHCT) alone versus patients undergoing NCHCT plus non-invasive vessel imaging (NVI) (including CT angiography (with or without CT perfusion) and magnetic resonance angiography). The primary outcome was the modified Rankin Scale (mRS) score at 90 days. Secondary outcomes included change in mRS score from baseline to 90 days, the proportions of mRS 0–1, 0–2, and 0–3, and dramatic clinical improvement at 24 hours. The safety outcomes were any intracranial hemorrhage (ICH), symptomatic ICH, and mortality within 90 days.ResultsA total of 894 patients met the inclusion criteria; 476 (53%) underwent NCHCT alone and 418 (47%) underwent NCHCT + NVI. In the NCHCT alone group, the door-to-reperfusion time was shorter by 47 min compared with the NCHCT + NVI group (219 vs 266 min, P<0.001). Patients in the NCHCT alone group showed a smaller increase in baseline mRS score at 90 days (median 3 vs 2 points; P=0.004) after adjustment. There were no significant differences between groups in the remaining clinical outcomes.ConclusionsIn patients selected for MT using NCHCT alone versus NCHCT + NVI, there were improved procedural outcomes and smaller increases in baseline mRS scores at 90 days.

Abstract MP58: Tissue And Sex Specific Effects Of Gstm1 Deletion In Mouse Models

Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Yves Wang ◽  
Nhu Nguyen ◽  
Keith Nehrke ◽  
Paul S Brookes ◽  
Thu H Le
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Enzymes ◽  
Mouse Model ◽  
Molecular Mechanisms ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Antioxidant Properties ◽  
Iri Model ◽  
Increased Risk ◽  
Study Gene Expression

The glutathione S-transferase ( Gst ) gene family encodes antioxidant enzymes. In humans, a common null allele deletion variant of GST μ-1 ( GSTM1 ) is highly prevalent across populations and is associated with increased risk and progression of various diseases. Using a Gstm1 knockout (KO) mouse model, we previously showed that KO mice with angiotensin II-induced hypertension (HTN) have increased kidney injury compared to wild-type (WT) controls, mediated by elevated oxidative stress. In the same mouse model, we have recently reported that in a Langendorff-perfused cardiac ischemia-reperfusion injury (IRI) model, where damage is also mediated by oxidative stress, male KO hearts are protected while females are not. Here, we investigated the molecular mechanisms for this difference in male hearts. WT and KO mice of both sexes were studied at 12-20 weeks of age. Hearts were snap frozen at baseline and after 25 min of global ischemia, and kidneys were collected at baseline and 4 weeks following HTN induction. A panel of 18 Gst genes were probed by qPCR from baseline hearts and kidneys of both sexes. Global metabolites were assayed using Metabolon, Inc. from hearts of both sexes and kidneys of males, at both baseline and diseased states. Analysis by qPCR (n = 3/group) showed that male, but not female, KO hearts had upregulation of other Gst s. In contrast, no significant differences between were found in male kidneys. Metabolomics (n = 6/group) detected 695 metabolites in hearts and 926 in kidneys. There were increases in several metabolites in KO vs. WT hearts including those with antioxidant properties. Notably, increases in carnosine and anserine were observed in KO male hearts but not in female hearts, while that of other antioxidant-related metabolites were observed in hearts of both sexes, but not in kidneys. HTN induced significant increases in metabolites in KO vs. WT kidneys in the pathways related to and linking methionine, cysteine, and glutathione, which were not observed in hearts. In this study, gene expression and metabolites suggest that the mechanisms compensating for the loss of GSTM1 are both tissue and sex specific. The resulting differences in antioxidant enzymes and metabolites may explain the unexpected protection for male Gstm1 KO hearts in IRI.

scholarly journals Up-regulation of miR-499a-5p decreases cerebral ischemia/reperfusion injury by targeting PDCD4

2021 ◽  
Author(s):  
Weifeng Shan ◽  
Huifeng Ge ◽  
Bingquan Chen ◽  
Linger Huang ◽  
Shaojun Zhu ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Cerebral Ischemia ◽  
Ischemia Reperfusion Injury ◽  
Cell Model ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Tunel Staining ◽  
Cerebral Ischemia Reperfusion

Abstract MiR-499a-5p was significantly down-regulated in degenerative tissues and correlated with apoptosis. Nonetheless, the biological function of miR-499a-5p in acute ischemic stroke has been still unclear. In this study, we found the plasma levels of miR-499a-5p were significantly down-regulated in 64 ischemic stroke patients and negatively correlated with the National Institutes of Health Stroke Scale score. Then, we constructed cerebral ischemia/reperfusion (I/R) injury in rats after middle cerebral artery occlusion and subsequent reperfusion and oxygen-glucose deprivation and reoxygenation (OGD/R) treated SH-SY5Y cell model. Transfection with miR-499a-5p mimic was accomplished by intracerebroventricular injection in the in vivo I/R injury model. We further found miR-499a-5p overexpression decreased infarct volumes and cell apoptosis in the in vivo I/R stroke model using TTC and TUNEL staining. PDCD4 was a direct target of miR-499a-5p by luciferase report assay and western blotting. Knockdown of PDCD4 reduced the infarct damage and cortical neuron apoptosis caused by I/R injury. MiR-499a-5p exerted neuroprotective roles mainly through inhibiting PDCD4-mediated apoptosis by CCK-8 assay, LDH release assay and flow cytometry analysis. These findings suggest that miR-499a-5p might represent a novel target that regulates brain injury by inhibiting PDCD4-mediating apoptosis.

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