Displaying publications 1 - 20 of 45 in total

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  1. Fulltext Platelet rich concentrate promotes early cellular proliferation and multiple lineage differentiation of human mesenchymal stromal cells in vitro
    Shani S, Ahmad RE, Naveen SV, Murali MR, Puvanan K, Abbas AA, et al.
    ScientificWorldJournal, 2014;2014:845293.
    PMID: 25436230 DOI: 10.1155/2014/845293
    Platelet rich concentrate (PRC) is a natural adjuvant that aids in human mesenchymal stromal cell (hMSC) proliferation in vitro; however, its role requires further exploration. This study was conducted to determine the optimal concentration of PRC required for achieving the maximal proliferation, and the need for activating the platelets to achieve this effect, and if PRC could independently induce early differentiation of hMSC. The gene expression of markers for osteocytes (ALP, RUNX2), chondrocytes (SOX9, COL2A1), and adipocytes (PPAR-γ) was determined at each time point in hMSC treated with 15% activated and nonactivated PRC since maximal proliferative effect was achieved at this concentration. The isolated PRC had approximately fourfold higher platelet count than whole blood. There was no significant difference in hMSC proliferation between the activated and nonactivated PRC. Only RUNX2 and SOX9 genes were upregulated throughout the 8 days. However, protein expression study showed formation of oil globules from day 4, significant increase in ALP at days 6 and 8 (P ≤ 0.05), and increased glycosaminoglycan levels at all time points (P < 0.05), suggesting the early differentiation of hMSC into osteogenic and adipogenic lineages. This study demonstrates that the use of PRC increased hMSC proliferation and induced early differentiation of hMSC into multiple mesenchymal lineages, without preactivation or addition of differentiation medium.
    Matched MeSH terms: Cell Differentiation/physiology*
  2. Engineering physical microenvironment for stem cell based regenerative medicine
    Han YL, Wang S, Zhang X, Li Y, Huang G, Qi H, et al.
    Drug Discov Today, 2014 Jun;19(6):763-73.
    PMID: 24508818 DOI: 10.1016/j.drudis.2014.01.015
    Regenerative medicine has rapidly evolved over the past decade owing to its potential applications to improve human health. Targeted differentiations of stem cells promise to regenerate a variety of tissues and/or organs despite significant challenges. Recent studies have demonstrated the vital role of the physical microenvironment in regulating stem cell fate and improving differentiation efficiency. In this review, we summarize the main physical cues that are crucial for controlling stem cell differentiation. Recent advances in the technologies for the construction of physical microenvironment and their implications in controlling stem cell fate are also highlighted.
    Matched MeSH terms: Cell Differentiation/physiology
  3. Fulltext Three-dimensional culture environment increases the efficacy of platelet rich plasma releasate in prompting skin fibroblast differentiation and extracellular matrix formation
    Rothan HA, Djordjevic I, Bahrani H, Paydar M, Ibrahim F, Abd Rahmanh N, et al.
    Int J Med Sci, 2014;11(10):1029-38.
    PMID: 25136258 DOI: 10.7150/ijms.8895
    Platelet rich plasma clot- releasate (PRCR) shows significant influence on tissue regeneration in clinical trials. Although, the mechanism of PRCR effect on fibroblast differentiation has been studied on 2D culture system, a detailed investigation is needed to establish the role of PRCR in cell seeded in 3D scaffolds. Therefore, a study was conducted to evaluate the influence of PRCR in fibroblasts (DFB) differentiation and extracellular matrix formation on both 3D and 2D culture systems. Cell viability was measured using MTT assay and DFB differentiation was evaluated by determining the expression levels of nucleostamin and alpha smooth muscle actin (α-SMA), using indirect immunostaining and Western blotting. The expression levels of extracellular matrix genes (collagen-I, collagen-III, fibronectin and laminin) and focal adhesion formation gene (integrin beta-1) were measured using Real-time PCR. The PRCR at 10% showed significant effect on cells viability compared with 5% and 20% in both culture environments. The decrease in the expression levels of nucleostamin and the increase in α-SMA signify the DFB differentiation to myofibroblast-like cells that was prominently greater in 3D compared to 2D culture. In 3D culture systems, the total collage production, expression levels of the extracellular matrix gene and the focal adhesion gene were increased significantly compared to 2D culture. In conclusion, 3D culture environments enhances the proliferative and differentiation effects of PRCR on DFB, thereby potentially increases the efficacy of DFB for future tissue engineering clinical application.
    Matched MeSH terms: Cell Differentiation/physiology*
  4. Fulltext Different isolation methods alter the gene expression profiling of adipose derived stem cells
    Gnanasegaran N, Govindasamy V, Musa S, Kasim NH
    Int J Med Sci, 2014;11(4):391-403.
    PMID: 24669199 DOI: 10.7150/ijms.7697
    Human adipose stem cells (ASCs) has been in the limelight since its discovery as a suitable source of mesenchymal stem cells (MSCs) in regenerative medicine. Currently, two major techniques are used to isolate ASCs, namely liposuction and tissue biopsy. These two methods are relatively risk-free but the question as to which method could give a more efficient output remains unclear. Thus, this study was carried out to compare and contrast the output generated in regards to growth kinetics, differentiation capabilities in vitro, and gene expression profiling. It was found that ASCs from both isolation methods were comparable in terms of growth kinetics and tri-lineage differentiation. Furthermore, ASCs from both populations were reported as CD44(+), CD73(+), CD90(+), CD166(+), CD34(-), CD45(-) and HLA-DR(-). However, in regards to gene expression, a group of overlapping genes as well as distinct genes were observed. Distinct gene expressions indicated that ASCs (liposuction) has endoderm lineage propensity whereas ASCs (biopsy) has a tendency towards mesoderm/ectoderm lineage. This information suggests involvement in different functional activity in accordance to isolation method. In conclusion, future studies to better understand these gene functions should be carried out in order to contribute in the applicability of each respective cells in regenerative therapy.
    Matched MeSH terms: Cell Differentiation/physiology
  5. Retropatellar fat pad-derived stem cells from older osteoarthritic patients have lesser differentiation capacity and expression of stemness genes
    Chua KH, Zaman Wan Safwani WK, Hamid AA, Shuhup SK, Mohd Haflah NH, Mohd Yahaya NH
    Cytotherapy, 2014 May;16(5):599-611.
    PMID: 24290076 DOI: 10.1016/j.jcyt.2013.08.013
    The use of retropatellar fat pad-derived mesenchymal stromal cells (RFMSCs) for cell-based therapy, particularly for cartilage repair, has been reported by several investigators in recent years. However, the effects of the donor's age and medical condition on the characteristics of RFMSCs have not been well established. The aim of this study was to determine whether age and medical condition can reduce the multipotential of stem cells isolated from the retropatellar fat pad.
    Matched MeSH terms: Cell Differentiation/physiology*
  6. Fulltext Alteration of cell cytoskeleton and functions of cell recovery of normal human osteoblast cells caused by factors associated with real space flight
    Kapitonova MY, Salim N, Othman S, Muhd Kamauzaman TM, Ali AM, Nawawi HM, et al.
    Malays J Pathol, 2013 Dec;35(2):153-63.
    PMID: 24362479 MyJurnal
    Experiments involving short-term space flight have shown an adverse effect on the physiology, morphology and functions of cells investigated. The causes for this effect on cells are: microgravity, temperature fluctuations, mechanical stress, hypergravity, nutrient restriction and others. However, the extent to which these adverse effects can be repaired by short-term space flown cells when recultured in conditions of normal gravity remains unclear. Therefore this study aimed to investigate the effect of short-term spaceflight on cytoskeleton distribution and recovery of cell functions of normal human osteoblast cells. The ultrastructure was evaluated using ESEM. Fluorescent staining was done using Hoechst, Mito Tracker CMXRos and Tubulin Tracker Green for cytoskeleton. Gene expression of cell functions was quantified using qPCR. As a result, recovered cells did not show any apoptotic markers when compared with control. Tubulin volume density (p<0.001) was decreased significantly when compared to control, while mitochondria volume density was insignificantly elevated. Gene expression for IL-6 (p<0.05) and sVCAM-1 (p<0.001) was significantly decreased while alkaline phosphatase (p<0.001), osteocalcin and sICAM (p<0.05) were significantly increased in the recovered cells compared to the control ones. The changes in gene and protein expression of collagen 1A, osteonectin, osteoprotegerin and beta-actin, caused by short-term spaceflight, were statistically not significant. These data indicate that short term space flight causes morphological changes in osteoblast cells which are consistent with hypertrophy, reduced cell differentiation and increased release of monocyte attracting proteins. The long-term effect of these changes on bone density and remodeling requires more detailed studies.
    Matched MeSH terms: Cell Differentiation/physiology
  7. Prospective full-term-derived pluripotent amniotic fluid stem (AFS) cells
    Ferdaos N, Nathan S, Nordin N
    Med J Malaysia, 2008 Jul;63 Suppl A:75-6.
    PMID: 19024991
    Amniotic fluid (AF) serves as an excellent alternative source of pluripotent stem cells, as they are not bound with ethical issues and the stem cells are more primitive than adult stem (AS) cells. Hence, they have higher potential. Here we aim to isolate and characterize pluripotent stem cells from mid-term and full-term pregnant rat amniotic fluid. The results demonstrate the evidence of heterogeneous population of cells in the amniotic fluid and some of the cells morphology shows similarity with ES cells.
    Matched MeSH terms: Cell Differentiation/physiology*
  8. Fulltext Cell therapy: the final frontier for treatment of neurological diseases
    Dutta S, Singh G, Sreejith S, Mamidi MK, Husin JM, Datta I, et al.
    CNS Neurosci Ther, 2013 Jan;19(1):5-11.
    PMID: 23253099 DOI: 10.1111/cns.12027
    Neurodegenerative diseases are devastating because they cause increasing loss of cognitive and physical functions and affect an estimated 1 billion individuals worldwide. Unfortunately, no drugs are currently available to halt their progression, except a few that are largely inadequate. This mandates the search of new treatments for these progressively degenerative diseases. Neural stem cells (NSCs) have been successfully isolated, propagated, and characterized from the adult brains of mammals, including humans. The confirmation that neurogenesis occurs in the adult brain via NSCs opens up fresh avenues for treating neurological problems. The proof-of-concept studies demonstrating the neural differentiation capacity of stem cells both in vitro and in vivo have raised widespread enthusiasm toward cell-based interventions. It is anticipated that cell-based neurogenic drugs may reverse or compensate for deficits associated with neurological diseases. The increasing interest of the private sector in using human stem cells in therapeutics is evidenced by launching of several collaborative clinical research activities between Pharma giants and research institutions or small start-up companies. In this review, we discuss the major developments that have taken place in this field to position stem cells as a prospective candidate drug for the treatment of neurological disorders.
    Matched MeSH terms: Cell Differentiation/physiology
  9. The use of bone marrow stem cells for bone tissue engineering
    Ng MH, Aminuddin BS, Tan KK, Tan GH, Sabarul Afian M, Ruszymah BH
    Med J Malaysia, 2004 May;59 Suppl B:41-2.
    PMID: 15468809
    Bone marrow stem cells (BMSC), known for its multipotency to differentiate into various mesenchymal cells such as chodrocyte, osteoblasts, adipocytes, etc, have been actively applied in tissue engineering. BMSC have been successfully isolated from bone marrow aspirate and bone marrow scraping from patients of various ages (13-56 years) with as little as 2ml to 5ml aspirate. BMSC isolated from our laboratory showed the presence of a heterogenous population that showed varying prevalence of surface antigens and the presence of telomerase activity albeit weak. Upon osteogenic induction, alkaline phosphatase activity and mineralization activity were observed.
    Matched MeSH terms: Cell Differentiation/physiology
  10. Towards engineering of a tracheal equivalent: identification of epithelial precursor cells, differentiation and cocultivation techniques
    Rotter N, Stölzel K, Endres M, Leinhase I, Ziegelaar BW, Sittinger M
    Med J Malaysia, 2004 May;59 Suppl B:35-6.
    PMID: 15468806
    Matched MeSH terms: Cell Differentiation/physiology
  11. Tissue engineering techniques in tendon and ligament replacement
    Goh JC, Ouyang HW, Toh SL, Lee EH
    Med J Malaysia, 2004 May;59 Suppl B:47-8.
    PMID: 15468812
    Matched MeSH terms: Cell Differentiation/physiology
  12. Differentiation of stem cells derived from carious teeth into dopaminergic-like cells
    Gnanasegaran N, Govindasamy V, Abu Kasim NH
    Int Endod J, 2016 Oct;49(10):937-49.
    PMID: 26354006 DOI: 10.1111/iej.12545
    AIM: To investigate whether dental pulp stem cells from carious teeth (DPSCs-CT) can differentiate into functional dopaminergic-like (DAergic) cells and provide an alternative cell source in regenerative medicine.

    METHODOLOGY: Dental pulp stem cells from healthy (DPSCs) and carious teeth (DPSCs-CT) were isolated from young donors. Both cell lines were expanded in identical culture conditions and subsequently differentiated towards DAergic-like cells using pre-defined dopaminergic cocktails. The dopaminergic efficiencies were evaluated both at gene and protein as well as at secretome levels.

    RESULTS: The efficiency of DPSCs-CT to differentiate into DAergic-like cells was not equivalent to that of DPSCs. This was further reflected in both gene and protein generation whereby key neuronal markers such as nestin, NURR1 and beta-III-tubulin were expressed significantly lower as compared to differentiated DPSCs (P cell communication family (APBB1).

    CONCLUSIONS: DPSCs-CT were able to differentiate into DAergic-like cells but not as efficiently as DPSCs. As such, prior to use in regenerative medicine, stem cells from any source should be thoroughly investigated beyond conventional benchmarks such as that proposed by the International Society for Cellular Therapy (ISCT).

    Matched MeSH terms: Cell Differentiation/physiology*
  13. Fulltext Isolation, characterization and the multi-lineage differentiation potential of rabbit bone marrow-derived mesenchymal stem cells
    Tan SL, Ahmad TS, Selvaratnam L, Kamarul T
    J Anat, 2013 Apr;222(4):437-50.
    PMID: 23510053 DOI: 10.1111/joa.12032
    Mesenchymal stem cells (MSCs) are recognized by their plastic adherent ability, fibroblastic-like appearance, expression of specific surface protein markers, and are defined by their ability to undergo multi-lineage differentiation. Although rabbit bone marrow-derived MSCs (rbMSCs) have been used extensively in previous studies especially in translational research, these cells have neither been defined morphologically and ultrastructurally, nor been compared with their counterparts in humans in their multi-lineage differentiation ability. A study was therefore conducted to define the morphology, surface marker proteins, ultrastructure and multi-lineage differentiation ability of rbMSCs. Herein, the primary rbMSC cultures of three adult New Zealand white rabbits (at least 4 months old) were used for three independent experiments. rbMSCs were isolated using the gradient-centrifugation method, an established technique for human MSCs (hMSCs) isolation. Cells were characterized by phase contrast microscopy observation, transmission electron microscopy analysis, reverse transcriptase-polymerase chain reaction (PCR) analysis, immunocytochemistry staining, flow cytometry, alamarBlue(®) assay, histological staining and quantitative (q)PCR analysis. The isolated plastic adherent cells were in fibroblastic spindle-shape and possessed eccentric, irregular-shaped nuclei as well as rich inner cytoplasmic zones similar to that of hMSCs. The rbMSCs expressed CD29, CD44, CD73, CD81, CD90 and CD166, but were negative (or dim positive) for CD34, CD45, CD117 and HLD-DR. Despite having similar morphology and phenotypic expression, rbMSCs possessed significantly larger cell size but had a lower proliferation rate as compared with hMSCs. Using established protocols to differentiate hMSCs, rbMSCs underwent osteogenic, adipogenic and chondrogenic differentiation. Interestingly, differentiated rbMSCs demonstrated higher levels of osteogenic (Runx2) and chondrogenic (Sox9) gene expressions than that of hMSCs (P cell types (P > 0.05). rbMSCs possess similar morphological characteristics to hMSCs, but have a higher potential for osteogenic and chondrogenic differentiation, despite having a lower cell proliferation rate than hMSCs. The characteristics reported here may be used as a comprehensive set of criteria to define or characterize rbMSCs.
    Matched MeSH terms: Cell Differentiation/physiology
  14. Mesenchymal stem cells: From stem cells to sarcomas
    Lye KL, Nordin N, Vidyadaran S, Thilakavathy K
    Cell Biol Int, 2016 Jun;40(6):610-8.
    PMID: 26992453 DOI: 10.1002/cbin.10603
    Mesenchymal stem cells (MSCs) have garnered vast interests in clinical settings, especially in regenerative medicine due to their unique properties-they are reliably isolated and expanded from various tissue sources; they are able to differentiate into mesodermal tissues such as bones, cartilages, adipose tissues, and muscles; and they have unique immunosuppressive properties. However, there are some concerns pertaining to the role of MSCs in the human body. On one hand, they are crucial component in the regeneration and repair of the human body. On the contrary, they are shown to transform into sarcomas. Although the exact mechanisms are still unknown, many new leads have pointed to the belief that MSCs do play a role in sarcomagenesis. This review focuses on the current updates and findings of the role of MSCs in their transformation process into sarcomas.
    Matched MeSH terms: Cell Differentiation/physiology
  15. The Advancement of Biomaterials in Regulating Stem Cell Fate
    Hiew VV, Simat SFB, Teoh PL
    Stem Cell Rev Rep, 2018 Feb;14(1):43-57.
    PMID: 28884292 DOI: 10.1007/s12015-017-9764-y
    Stem cells are well-known to have prominent roles in tissue engineering applications. Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) can differentiate into every cell type in the body while adult stem cells such as mesenchymal stem cells (MSCs) can be isolated from various sources. Nevertheless, an utmost limitation in harnessing stem cells for tissue engineering is the supply of cells. The advances in biomaterial technology allows the establishment of ex vivo expansion systems to overcome this bottleneck. The progress of various scaffold fabrication could direct stem cell fate decisions including cell proliferation and differentiation into specific lineages in vitro. Stem cell biology and biomaterial technology promote synergistic effect on stem cell-based regenerative therapies. Therefore, understanding the interaction of stem cell and biomaterials would allow the designation of new biomaterials for future clinical therapeutic applications for tissue regeneration. This review focuses mainly on the advances of natural and synthetic biomaterials in regulating stem cell fate decisions. We have also briefly discussed how biological and biophysical properties of biomaterials including wettability, chemical functionality, biodegradability and stiffness play their roles.
    Matched MeSH terms: Cell Differentiation/physiology
  16. A miRNA-145/TGF-β1 negative feedback loop regulates the cancer-associated fibroblast phenotype
    Melling GE, Flannery SE, Abidin SA, Clemmens H, Prajapati P, Hinsley EE, et al.
    Carcinogenesis, 2018 05 28;39(6):798-807.
    PMID: 29506142 DOI: 10.1093/carcin/bgy032
    The dissemination of cancer cells to local and distant sites depends on a complex and poorly understood interplay between malignant cells and the cellular and non-cellular components surrounding them, collectively termed the tumour microenvironment. One of the most abundant cell types of the tumour microenvironment is the fibroblast, which becomes corrupted by locally derived cues such as TGF-β1 and acquires an altered, heterogeneous phenotype (cancer-associated fibroblasts, CAF) supportive of tumour cell invasion and metastasis. Efforts to develop new treatments targeting the tumour mesenchyme are hampered by a poor understanding of the mechanisms underlying the development of CAF. Here, we examine the contribution of microRNA to the development of experimentally-derived CAF and correlate this with changes observed in CAF derived from tumours. Exposure of primary normal human fibroblasts to TGF-β1 resulted in the acquisition of a myofibroblastic CAF-like phenotype. This was associated with increased expression of miR-145, a miRNA predicted in silico to target multiple components of the TGF-β signalling pathway. miR-145 was also overexpressed in CAF derived from oral cancers. Overexpression of miR-145 blocked TGF-β1-induced myofibroblastic differentiation and reverted CAF towards a normal fibroblast phenotype. We conclude that miR-145 is a key regulator of the CAF phenotype, acting in a negative feedback loop to dampen acquisition of myofibroblastic traits, a key feature of CAF associated with poor disease outcome.
    Matched MeSH terms: Cell Differentiation/physiology
  17. Stem Cells Derived from Amniotic Fluid: A Potential Pluripotent-Like Cell Source for Cellular Therapy?
    Ramasamy TS, Velaithan V, Yeow Y, Sarkar FH
    Curr Stem Cell Res Ther, 2018;13(4):252-264.
    PMID: 29336267 DOI: 10.2174/1574888X13666180115093800
    BACKGROUND: Regenerative medicine aims to provide therapeutic treatment for disease or injury, and cell-based therapy is a newer therapeutic approach different from conventional medicine. Ethical issues that rose by the utilisation of human embryonic stem cells (hESC) and the limited capacity of adult stem cells, however, hinder the application of these stem cells in regenerative medicine. Recently, isolation and characterisation of c-kit positive cells from human amniotic fluid, which possess intermediate characteristics between hESCs and adult stem cells, provided a new approach towards realising their promise for fetal and adult regenerative medicine. Despite the number of studies that have been initiated to characterize their molecular signature, research on developing approaches to maintain and enhance their regenerative potential is urgently needed and must be developed.

    AIM: Thus, this review is focused on understanding their potential uses and factors influencing their pluripotent status in vitro.

    CONCLUSION: In short, this cell source could be an ideal cellular resource for pluripotent cells for potential applications in allogeneic cellular replacement therapies, fetal tissue engineering, pharmaceutical screening, and in disease modelling.

    Matched MeSH terms: Cell Differentiation/physiology*
  18. Hypoxia enhances the viability, growth and chondrogenic potential of cryopreserved human adipose-derived stem cells
    Wan Safwani WKZ, Choi JR, Yong KW, Ting I, Mat Adenan NA, Pingguan-Murphy B
    Cryobiology, 2017 04;75:91-99.
    PMID: 28108309 DOI: 10.1016/j.cryobiol.2017.01.006
    Cryopreservation is the only existing method of storage of human adipose-derived stem cells (ASCs) for clinical use. However, cryopreservation has been shown to be detrimental to ASCs, particularly in term of cell viability. To restore the viability of cryopreserved ASCs, it is proposed to culture the cells in a hypoxic condition. To this end, we aim to investigate the effect of hypoxia on the cryopreserved human ASCs in terms of not only cell viability, but also their growth and stemness properties, which have not been explored yet. In this study, human ASCs were cultured under four different conditions: fresh (non-cryopreserved) cells cultured in 1) normoxia (21% O2) and 2) hypoxia (2% O2) and cryopreserved cells cultured in 3) normoxia and 4) hypoxia. ASCs at passage 3 were subjected to assessment of viability, proliferation, differentiation, and expression of stemness markers and hypoxia-inducible factor-1 alpha (HIF-1α). We found that hypoxia enhances the viability and the proliferation rate of cryopreserved ASCs. Further, hypoxia upregulates HIF-1α in cryopreserved ASCs, which in turn activates chondrogenic genes to promote chondrogenic differentiation. In conclusion, hypoxic-preconditioned cryopreserved ASCs could be an ideal cell source for cartilage repair and regeneration.
    Matched MeSH terms: Cell Differentiation/physiology
  19. Fulltext Nasal epithelial cells can act as a physiological surrogate for paediatric asthma studies
    Thavagnanam S, Parker JC, McBrien ME, Skibinski G, Shields MD, Heaney LG
    PLoS One, 2014;9(1):e85802.
    PMID: 24475053 DOI: 10.1371/journal.pone.0085802
    Differentiated paediatric epithelial cells can be used to study the role of epithelial cells in asthma. Nasal epithelial cells are easier to obtain and may act as a surrogate for bronchial epithelium in asthma studies. We assessed the suitability of nasal epithelium from asthmatic children to be a surrogate for bronchial epithelium using air-liquid interface cultures.
    Matched MeSH terms: Cell Differentiation/physiology
  20. Fulltext Transfected human mesenchymal stem cells do not lose their surface markers and differentiation properties
    Yap FL, Cheong SK, Ammu R, Leong CF
    Malays J Pathol, 2009 Dec;31(2):113-20.
    PMID: 20514854 MyJurnal
    In this study, we evaluated the biological properties of human mesenchymal stem cells transfected (hMSC) with a plasmid vector expressing human cytokine interleukin-12 (IL-12). Surface markers were analysed by immunophenotyping using flow cytometry. Differentiation capability was evaluated towards adipogenesis and osteogenesis. We demonstrated that successfully transfected hMSC retained their surface immunophenotypes and differentiation potential into adipocytes and osteocytes. These results indicate that hMSC may be a suitable vehicle for gene transduction.
    Matched MeSH terms: Cell Differentiation/physiology
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