Displaying publications 21 - 40 of 403 in total

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  1. Munisamy S, Radhakrishnan AK, Ramdas P, Samuel PJ, Singh VA
    Curr Oncol, 2022 Aug 05;29(8):5585-5603.
    PMID: 36005179 DOI: 10.3390/curroncol29080441
    The main role of the host immune system is to identify and eliminate cancer cells, which is a complex process, but it is not a fail-safe mechanism. Many sarcoma patients succumb to this disease despite treatments rendered. The aim of this pilot study was to compare the levels of CD4+ T-cells, T-regulatory (Treg) cells, and cytokines such as tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), interleukin-17A (IL-17A), and transforming growth factor-beta-1 (TGF-β1) in peripheral blood leukocytes of sarcoma patients and healthy controls. For gene expression studies, total ribonucleic acid (RNA) was extracted from peripheral blood leukocytes and genes that were differentially regulated in peripheral blood leukocytes of sarcoma patients compared with healthy controls were determined using a commercial T-helper cell differentiation quantitative polymerase chain reaction (qPCR) array. Flow cytometer analysis was performed on blood samples from 26 sarcoma patients and 10 healthy controls to identify the levels of CD4+ T-cells and T-reg cells. The level of cytokines in plasma and culture supernatant were quantified using commercial enzyme-linked immunosorbent assay (ELISA) kits. A marked reduction in the percentage of CD4+ T-cells (p = 0.037) and levels of TNF-α (p = 0.004) and IFN-γ (0.010) was observed in sarcoma patients. Gene expression analysis showed five genes (homeobox A10 (HOXA10), GATA binding protein 3 (GATA3), prostaglandin D2 receptor 2 (PTGDR2), thymocyte selection associated high mobility group box (TOX), and C-C motif chemokine receptor 3 (CCR3)) were dysregulated (p < 0.05) in sarcoma patients. This study suggests that T-helper-1 immune responses are reduced in sarcoma patients.
    Matched MeSH terms: Tumor Necrosis Factor-alpha*
  2. Wee CL, Azemi AK, Mokhtar SS, Yahaya S, Yaacob NS, Rasool AHG
    Microvasc Res, 2023 Nov;150:104574.
    PMID: 37390963 DOI: 10.1016/j.mvr.2023.104574
    Low vitamin D (vitD) levels have been reported to be a risk factor for diabetes-related cardiovascular complications. This study examined the effects of vitD deficiency on oxidative stress (OS), inflammation, and levels of the vasoconstrictor angiotensin II (Ang II) in the microvascular tissue of type 2 diabetic patients. Patients were categorized into (i) vitD non-deficient diabetics (DNP, n = 10) and (ii) vitD-deficient diabetics (DDP, n = 10), based on their serum 25(OH)D levels. Subcutaneous fat tissues with intact blood vessels were collected during lower limb surgical procedures. The blood vessel were isolated; measurements of the antioxidant enzyme superoxide dismutase (SOD) activity, OS marker malondialdehyde (MDA), Ang II, and the inflammatory marker, TNF-α of the microvascular tissues were determined. Elevated MDA levels and reduced SOD activity, with higher levels of TNF-α and Ang II were observed in the microvascular tissues of DDP compared to DNP. VitD deficiency did not associate with glycemic parameters (fasting blood glucose and glycated hemoglobin) levels. In conclusion, vitD deficiency was correlated with higher microvascular tissue OS, inflammation, and Ang II levels in type 2 diabetic patients. This may contribute to early vasculopathy that occurs in diabetic patients, thus, may contribute to the planning of therapeutic strategies to delay or prevent cardiovascular complications.
    Matched MeSH terms: Tumor Necrosis Factor-alpha/pharmacology
  3. Ahmed HMA, El-Karim I, Duncan HF, Krastl G, Galler K
    Clin Oral Investig, 2023 Nov;27(11):6357-6369.
    PMID: 37870593 DOI: 10.1007/s00784-023-05284-9
    OBJECTIVES: This review aims to discuss the implications of anatomy of the root, pulp chamber, and canals on pulpotomy and revitalization procedures (RPs) as treatment alternatives to root canal treatment procedures.

    METHODS: This narrative review was undertaken to address two main questions - why remove vital pulp tissue in teeth with complex canal anatomy when it can be preserved? And why replace the necrotic pulp in teeth with mature roots with a synthetic material when we can revitalize? This review also aims to discuss anatomical challenges with pulpotomy and revitalization procedures.

    RESULTS: Maintaining the vitality of the pulp via partial or full pulpotomy procedures avoids the multiple potential challenges faced by clinicians during root canal treatment. However, carrying out pulpotomy procedures requires a meticulous understanding of the pulp chamber anatomy, which varies from tooth to tooth. Literature shows an increased interest in the application of RPs in teeth with mature roots; however, to date, the relation between the complexity of the root canal system and outcomes of RPs in necrotic multi-rooted teeth with mature roots is unclear and requires further robust comparative research and long-term follow-up.

    CONCLUSIONS: Whenever indicated, pulpotomy procedures are viable treatment options for vital teeth with mature roots; however, comparative, adequately powered studies with long-term follow-up are needed as a priority in this area. RPs show promising outcomes for necrotic teeth with mature roots that warrant more evidence in different tooth types with long-term follow-ups.  CLINICAL RELEVANCE: Clinicians should be aware of the pulp chamber anatomy, which is subject to morphological changes by age or as a defensive mechanism against microbial irritation, before practicing partial and full pulpotomy procedures. RP is a promising treatment option for teeth with immature roots, but more evidence is needed for its applications in teeth with mature roots. A universal consensus and considerably more robust evidence are needed for the standardization of RPs in teeth with mature roots.

    Matched MeSH terms: Dental Pulp Necrosis/therapy
  4. Naing C, Htet NH, Siew Tung W, Basavaraj AK, Mak JW
    PLoS One, 2018;13(10):e0205413.
    PMID: 30300401 DOI: 10.1371/journal.pone.0205413
    Individual studies have assessed the association between TNF-α-308G>A and TNF-α-238 G>A polymorphisms and severity of dengue infection. However, the results are inconclusive and most studies had small sample sizes. The objective of this study was to summarize the evidence of association between TNF-α-308 G>A and TNF-α-238 G>A and severity of dengue infection. This study follows the preferred reporting items for systematic reviews and meta- analyses of genetic association studies, recommended by PLOS One. We calculated pooled odds ratio and its 95% confidence interval (CI) to estimate the association between TNF-α-308 G>A or TNF-α-238 G>A and the risk of severe dengue infections. To determine the information size required for this meta-analysis study, a trial sequential analysis (TSA) was done. Eight studies (640 cases and 1275 controls), which assessed the association of TNF-α-308 G>A or TNF-α-238 G>A and the risk of DHF were included. Overall, we found no significant association between TNF-α-308 G>A and the DHF risk in the allelic model (OR, 0.91; 95% CI, 0.51-1.63), the recessive model (OR,1.32;95%CI,0.73-2.37), the dominant model (OR,0.93;95%CI:0.59-1.47) or the additive model (OR,1.43,95;95%CI:0.79-2.59). There was also no significant association between TNF-α-238 G>A and DHF risk under the allele contrast model (OR:1.51;95%CI:0.88-2.58), the recessive model (OR,1.48,95% CI:0.33-6.58), the dominant model (OR,1.48;95%CI:0.56-3.92), or the additive model (OR:1.5;95%CI:0.34-6.69). On subgroup analysis, neither the Asian population nor the non-Asian population showed significant association between TNF-α-308 G>A/TNF-α-238 G>A and the DHF risk under any genetic models. Leave-one-out meta-analysis showed stability of the results. TSA plots suggested that the sample size in this meta-analysis study was below the required information size. The findings suggest an inclusive evidence of the association between TNF-α-308/ TNF-α-238 G>A and the risk of developing severe dengue infection. Large studies with evidence of Hardy-Weinberg equilibrium, assessing gene-gene interactions are recommended.
    Matched MeSH terms: Tumor Necrosis Factor-alpha/genetics*
  5. M Yusoff NNF, Ahmad S, Wan Abdul Rahman WF, Mohamud R, C Boer J, Plebanski M, et al.
    Cytokine, 2024 Jun;178:156557.
    PMID: 38452440 DOI: 10.1016/j.cyto.2024.156557
    Chronic rhinosinusitis with nasal polyps (CRSwNP) is a subtype of chronic rhinosinusitis (CRS) characterized by the presence of nasal polyps (NP) in the paranasal mucosa. Despite the complex etiology, NP is believed to result from chronic inflammation. The long-term aftermath of the type 2 response is responsible for symptoms seen in NP patients, i.e. rhinorrhea, hyposmia, and nasal obstruction. Immune cellular tolerogenic mechanisms, particularly CD4 + Foxp3 + regulatory T cells (Tregs), are crucial to curtail inflammatory responses. Current evidence suggests impaired Treg activity is the main reason underlying the compromise of self-tolerance, contributing to the onset of CRSwNP. There is compelling evidence that tumor necrosis factor 2 (TNFR2) is preferentially expressed by Tregs, and TNFR2 is able to identify the most potent suppressive subset of Tregs. Tumor necrosis factor (TNF)-TNFR2 interaction plays a decisive role in the activation and expansion of Tregs. This review summarizes current understanding of Tregs biology, focusing on the discussion of the recent advances in the study of TNF-TNFR2 axis in the upregulation of Treg function as a negative feedback mechanism in the control of chronic inflammation. The role of dysregulation of Tregs in the immunopathogenesis of CRSwNP will be analyzed. The future perspective on the harnessing Tregs-mediated self-tolerant mechanism in the management of CRSwNP will be introduced.
    Matched MeSH terms: Tumor Necrosis Factor-alpha; Receptors, Tumor Necrosis Factor, Type II
  6. Malerba G, Basilico M, Bonfiglio N, Maccauro G
    Malays Orthop J, 2020 Nov;14(3):177-179.
    PMID: 33403082 DOI: 10.5704/MOJ.2011.029
    Isolated apophyseal avulsion of the greater trochanter is a rare condition in the paediatric population, frequently related to avascular necrosis of the femoral head. Since there are few cases in the literature, there is no consensus regarding the best treatment of this injury. Our study describes the case of a 9-year-old patient with an avulsion of the right greater trochanter. A minimally invasive osteosynthesis was performed, achieving complete clinical and radiographic healing of the patient and no long-term complications after four years.
    Matched MeSH terms: Femur Head Necrosis
  7. Yong CY, Ong HK, Tang HC, Yeap SK, Omar AR, Ho KL, et al.
    PeerJ, 2019;7:e7151.
    PMID: 31341728 DOI: 10.7717/peerj.7151
    The aquaculture of salmonid fishes is a multi-billion dollar industry with production over 3 million tons annually. However, infectious hematopoietic necrosis virus (IHNV), which infects and kills salmon and trout, significantly reduces the revenue of the salmon farming industry. Currently, there is no effective treatment for IHNV infected fishes; therefore, early detection and depopulation of the infected fishes remain the most common practices to contain the spread of IHNV. Apart from hygiene practices in aquaculture and isolation of infected fishes, loss of fishes due to IHNV infection can also be significantly reduced through vaccination programs. In the current review, some of the diagnostic methods for IHNV, spanning from clinical diagnosis to cell culture, serological and molecular methods are discussed in detail. In addition, some of the most significant candidate vaccines for IHNV are also extensively discussed, particularly the DNA vaccines.
    Matched MeSH terms: Infectious hematopoietic necrosis virus
  8. Ng SY, D'Arcy C, Orchard D
    Australas J Dermatol, 2015 Nov;56(4):e102-4.
    PMID: 24635514 DOI: 10.1111/ajd.12159
    Lipoatrophic panniculitis is a rare condition affecting mainly children, often associated with connective tissue disease. We report a healthy 12-month-old girl with no clinical or laboratory features of connective tissue disease who presented with the progressive appearance of annular atrophic plaques beginning at the left arm. A histopathological analysis revealed lobular panniculitis, with fat necrosis and an associated inflammatory infiltrate supporting the diagnosis of lipoatrophic panniculitis. Lipoatrophic panniculitis should be considered in infants and young children with clinical features of panniculitis and fat atrophy even without clinical or serologic evidence of connective tissue disease.
    Matched MeSH terms: Fat Necrosis
  9. Badaruddin A, Choo MM
    Malays Fam Physician, 2021 Mar 25;16(1):117-120.
    PMID: 33948150 DOI: 10.51866/cr1108
    Otitis externa is an infection of the external auditory canal. It rarely results in facial palsy except in severe cases such as necrotizing otitis externa, which is a life-threatening invasive infection of the external auditory canal. Early recognition with prompt and appropriate treatment of necrotizing otitis externa is crucial to prevent more sinister complications. Here we report a case of an elderly gentleman who presented with otitis externa and developed facial palsy a month later. We identified possible problems that may have led to the complication so that such an occurrence can be prevented in the future.
    Matched MeSH terms: Necrosis
  10. Yap WY, Hwang JS
    Molecules, 2018 Oct 04;23(10).
    PMID: 30287801 DOI: 10.3390/molecules23102537
    A group of stable, water-soluble and membrane-bound proteins constitute the pore forming toxins (PFTs) in cnidarians. They interact with membranes to physically alter the membrane structure and permeability, resulting in the formation of pores. These lesions on the plasma membrane causes an imbalance of cellular ionic gradients, resulting in swelling of the cell and eventually its rupture. Of all cnidarian PFTs, actinoporins are by far the best studied subgroup with established knowledge of their molecular structure and their mode of pore-forming action. However, the current view of necrotic action by actinoporins may not be the only mechanism that induces cell death since there is increasing evidence showing that pore-forming toxins can induce either necrosis or apoptosis in a cell-type, receptor and dose-dependent manner. In this review, we focus on the response of the cellular immune system to the cnidarian pore-forming toxins and the signaling pathways that might be involved in these cellular responses. Since PFTs represent potential candidates for targeted toxin therapy for the treatment of numerous cancers, we also address the challenge to overcoming the immunogenicity of these toxins when used as therapeutics.
    Matched MeSH terms: Necrosis/drug therapy; Necrosis/immunology*; Necrosis/pathology
  11. Dewi IP, Wahyuni FS, Aldi Y, Ismail NH, Dachriyanus
    J Complement Integr Med, 2023 Jun 01;20(2):365-371.
    PMID: 36750417 DOI: 10.1515/jcim-2022-0419
    OBJECTIVES: The objective of this study is to determine the activity of Garcinia cowa Roxb. n-hexane, ethyl acetate, and butanol fractions as an immunomodulator in vitro and obtain the fraction that has the potential as an immunomodulator.

    METHODS: Raw 264.7 macrophages were used to asses G. cowa Roxb. immunomodulatory activity. The MTT assay was chosen to measure cell viability to evaluate the cytotoxic effect on cells. ELISA method was used to measure the concentration of Interleukin-6 (IL-6) and Tumor Necrosis Factor Alpha (TNF-α) secreted by cells after being treated with G. cowa Roxb. fraction. The neutral red uptake assay determined the effect of Garcinia cowa Roxb. on the phagocytic activity.

    RESULTS: After Raw 264.7 macrophages were given the Hexan fraction (Hex) at concentrations of 12.5 and 25 μg/mL, there was a decrease in the concentration of IL-6, TNF-α, and the phagocytosis index of cells. Administration of the Ethyl Acetate fraction (EtOAc) at concentrations of 12.5 and 25 μg/mL on cells caused a decrease in IL-6 and TNF-α levels but did not affect the phagocytosis index. There was an increase in the level of TNF-α and the phagocytosis index after being given the Butanol fraction (BuOH) with concentrations of 12.5 and 25 μg/mL but there was a slight decrease in the level of IL-6.

    CONCLUSIONS: Both Hex and EtOAc fractions could suppress immune responses through decreasing IL-6, TNF-α, and slightly decreased phagocytic activity. BuOH fraction could stimulate immunomodulatory activities through enhanced TNF-α levels and phagocytic index, but less potent in enhancing IL-6 production. The BuOH fraction could be developed as an immunostimulant.

    Matched MeSH terms: Tumor Necrosis Factor-alpha
  12. Gan RK, Sanchez Martinez A, Abu Hasan MA, Castro Delgado R, Arcos González P
    J Ultrasound, 2023 Jun;26(2):343-353.
    PMID: 36694072 DOI: 10.1007/s40477-022-00761-5
    INTRODUCTION: Necrotizing fasciitis (NF) is a rapidly progressive necrosis of the fascial layer with a high mortality rate. It is a life-threatening medical emergency that requires urgent treatment. Lack of skin finding in NF made diagnosis difficult and required a high clinical index of suspicion. The use of ultrasound may guide clinicians in improving diagnostic speed and accuracy, thus leading to improved management decisions and patient outcomes. This literature search aims to review the use of point-of-care ultrasonography in diagnosing necrotizing fasciitis.

    METHOD: We searched relevant electronic databases, including PUBMED, MEDLINE, and SCOPUS, and performed a systematic review. Keywords used were "necrotizing fasciitis" or "necrotising fasciitis" or "necrotizing soft tissue infections" and "point-of-care ultrasonography" "ultrasonography" or "ultrasound". No temporal limitation was set. An additional search was performed via google scholar, and the top 100 entry was screened.

    RESULTS: Among 540 papers screened, only 21 were related to diagnosing necrotizing fasciitis using ultrasonography. The outcome includes three observational studies, 16 case reports, and two case series, covering the period from 1976 to 2022.

    CONCLUSION: Although the use of ultrasonography in diagnosing NF was published in several papers with promising results, more studies are required to investigate its diagnostic accuracy and potential to reduce time delay before surgical intervention, morbidity, and mortality.

    Matched MeSH terms: Necrosis
  13. Zakaria ZA, Rofiee MS, Somchit MN, Zuraini A, Sulaiman MR, Teh LK, et al.
    PMID: 21318140 DOI: 10.1155/2011/142739
    The present study aims to determine the hepatoprotective effect of MARDI-produced virgin coconut oils, prepared by dried- or fermented-processed methods, using the paracetamol-induced liver damage in rats. Liver injury induced by 3 g/kg paracetamol increased the liver weight per 100 g bodyweight indicating liver damage. Histological observation also confirms liver damage indicated by the presence of inflammations and necrosis on the respective liver section. Interestingly, pretreatment of the rats with 10, but not 1 and 5, mL/kg of both VCOs significantly (P < .05) reduced the liver damage caused by the administration of paracetamol, which is further confirmed by the histological findings. In conclusion, VCO possessed hepatoprotective effect that requires further in-depth study.
    Matched MeSH terms: Necrosis
  14. Ahmed S, Othman NH
    PMID: 24363771 DOI: 10.1155/2013/829070
    The main treatment for cancer is by using chemotherapy and radiotherapy which themselves are toxic to other viable cells of the body. Recently, there are many studies focusing on the use of natural products for cancer prevention and treatment. Of these natural products, honey has been extensively researched. The mechanism of the anti-cancer activity of honey as chemopreventive and therapeutic agent has not been completely understood. The possible mechanisms are due to its apoptotic, antiproliferative, antitumor necrosis factor (anti-TNF), antioxidant, anti-inflammatory, estrogenic and immunomodulatory activities. We collate the findings of several studies published in the literature in order to understand the mechanism of its action.
    Matched MeSH terms: Tumor Necrosis Factor-alpha
  15. Yuen NS, Ibrahim SB
    Arch Pediatr Adolesc Med, 2011 Jun;165(6):563-4.
    PMID: 21646590 DOI: 10.1001/archpediatrics.2011.80-a
    Matched MeSH terms: Fat Necrosis/congenital; Fat Necrosis/pathology*
  16. Bastion ML
    BMJ Case Rep, 2010;2010.
    PMID: 22736756 DOI: 10.1136/bcr.11.2009.2488
    This report describes the rapid progress of a case of unilateral acute retinal necrosis (ARN) that led to formation of a macular hole rhegmatogenous retinal detachment with advanced proliferative vitreo-retinopathy (PVR) changes over the space of 2 weeks. This necessitated primary vitrectomy with circumferential scleral buckle placement, which facilitated reattachment of the retina.
    Matched MeSH terms: Retinal Necrosis Syndrome, Acute/complications*; Retinal Necrosis Syndrome, Acute/surgery*
  17. Rahman ZA, Abdullah N, Singh R, Sosroseno W
    J Oral Sci, 2010 Mar;52(1):133-6.
    PMID: 20339244
    The aim of the present study was to assess the levels of salivary cortisol, tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) before, during and after acute exercise. Acute exercise was induced using a standard treadmill test with Bruce protocol in ten physically active male participants. Unstimulated saliva was collected before, during and after exercise. The levels of salivary cortisol and TNF-alpha were assessed by enzyme immunoassays. Salivary NO was determined by the Griess reagent. The results showed that both salivary cortisol and TNF-alpha increased and peaked at 14 min during exercise and then decreased. The levels of NO were increased up to 1 h after exercise and subsequently lowered after 24 h. The results of the present study suggest that acute exercise may induce high levels of salivary cortisol, TNF-alpha and NO.
    Matched MeSH terms: Tumor Necrosis Factor-alpha/analysis; Tumor Necrosis Factor-alpha/secretion*
  18. Montazeri S, Nalliah S, Radhakrishnan AK
    Diabetes Res Clin Pract, 2010 May;88(2):139-45.
    PMID: 20189261 DOI: 10.1016/j.diabres.2010.01.028
    OBJECTIVE: The aim of this study is to investigate if an association exists between single nucleotide polymorphism (SNP) in the tumor necrosis factor-alpha (TNF-alpha) and TNF-beta genes.
    METHODS: The DNA was extracted and SNP in the human TNF-alpha and TNF-beta genes at positions -308 (G/A) and 252 (A/G), respectively, was analyzed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Plasma levels of TNF-alpha in different stages of pregnancy were quantified using enzyme linked immunosorbent assay (ELISA).
    RESULTS: There was no significant difference in genotype and allele frequency of SNP at position -308 (G/A) in the promoter region of the human TNF-alpha gene as well as the SNP at position 252 (A/G) in the human TNF-beta gene between the GDM and control subjects. Using the logistic regression model, it was found that the SNP in the TNF-alpha as well as TNF-beta were not associated with development of GDM. In addition, the TNF-alpha levels in the plasma of GDM and control mothers were not significantly different.
    CONCLUSIONS: In the population studied, the SNP in position -308 (G/A) of the human TNF-alpha or in position 252 (A/G) of the human TNF-beta gene is not an independent risk factor or a predictor for GDM.
    Matched MeSH terms: Tumor Necrosis Factor-alpha/blood; Tumor Necrosis Factor-alpha/genetics*
  19. Fong LY, Ng CT, Zakaria ZA, Baharuldin MT, Arifah AK, Hakim MN, et al.
    Phytother Res, 2015 Oct;29(10):1501-8.
    PMID: 26171791 DOI: 10.1002/ptr.5404
    The increase in endothelial permeability often promotes edema formation in various pathological conditions. Tumor necrosis factor-alpha (TNF-α), a pro-atherogenic cytokine, impairs endothelial barrier function and causes endothelial dysfunction in early stage of atherosclerosis. Asiaticoside, one of the triterpenoids derived from Centella asiatica, is known to possess antiinflammatory activity. In order to examine the role of asiaticoside in preserving the endothelial barrier, we assessed its effects on endothelial hyperpermeability and disruption of actin filaments evoked by TNF-α in human aortic endothelial cells (HAEC). TNF-α caused an increase in endothelial permeability to fluorescein isothiocyanate (FITC)-dextran. Asiaticoside pretreatment significantly suppressed TNF-α-induced increased permeability. Asiaticoside also prevented TNF-α-induced actin redistribution by suppressing stress fiber formation. However, the increased F to G actin ratio stimulated by TNF-α was not changed by asiaticoside. Cytochalasin D, an actin depolymerizing agent, was used to correlate the anti-hyperpermeability effect of asiaticoside with actin cytoskeleton. Surprisingly, asiaticoside failed to prevent cytochalasin D-induced increased permeability. These results suggest that asiaticoside protects against the disruption of endothelial barrier and actin rearrangement triggered by TNF-α without a significant change in total actin pool. However, asiaticoside seems to work by other mechanisms to maintain the integrity of endothelial barrier rather than stabilizing the F-actin organization.
    Matched MeSH terms: Tumor Necrosis Factor-alpha/antagonists & inhibitors*; Tumor Necrosis Factor-alpha/pharmacology
  20. Jayalakshmi P, Ting HC
    Histopathology, 1990 Jul;17(1):89-91.
    PMID: 2146206
    Matched MeSH terms: Necrosis/chemically induced; Necrosis/pathology
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