scholarly journals Two applications of developmental genetics to paleontology: segmentation genes in molluscs and preoral appendages in taxa of uncertain affinity

1992 ◽  
Vol 6 ◽  
pp. 145-145 ◽  
Author(s):  
David K. Jacobs
Keyword(s):  
Fossil Record ◽  
De Novo ◽  
Ectopic Expression ◽  
Cell Types ◽  
The Body ◽  
Developmental Genetics ◽  
Switching Function ◽  
Developmental Sequence ◽  
Homologous Genes ◽  
Organ Systems

Resolution of deep evolutionary problems, including the origin of the metazoa and the morphologic evolution of higher taxa within the metazoa, have long been sought in the developmental sequence. Haeckel's gastraea theory is perhaps the best example of this endeavor. Since Haeckel's time it has become apparent that the early evolution of animal life cannot be read directly from the developmental sequence. Ontogeny itself evolves making it difficult to even identify homologies in the early development between many phyla and classes. However, all may not be lost; during metazoan development gene expression must be localized in order to differentiate cell types in the body during development. It is this regionalized transcription and translation to protein product that differentiates cell types, organ systems, and the morphologic features that we can identify in the fossil record. The functional importance of the genes in question, and the fact that portions of the protein products of these genes must bind to DNA in order to perform their switching function, leads to extreme sequence conservation. This permits the identification and comparison of homologous genes important in the development of divergent taxa even after the passage of the entire Phanerozoic. If these genes retain a pattern of expression in development as well as conservation of the DNA sequence, then we can identify a homologous process derived from the development of the shared ancestor of the two taxa.This approach can be used to address the homology of metameric units. Preliminary results indicate that the segmentation gene engrailed is expressed in chiton trochophores in associated with each of the developing plate fields. The engrailed gene is known to control segmentation processes in arthropods and annelids. Evidently the plates in chitons evolved from serial features in a shared ancestor of annelids, arthropods and molluscs. This indicates that the serial features found in molluscs are ancestral (plesiomorphic), and that the evolution of the mollusca has involved the loss or reduction of serial features rather than their de novo evolution in chitons and monoplacophorans as has been suggested by a number of neontologists. The fossil record suggests successive reduction of serial features in molluscs. This paleontological interpretation now finds support in developmental genetics.Developmental genetics also provides a basis for evolution of body plans. Unusual preoral appendages have evolved in chelicerates, Burgess Shale arthropods such as Yohoia and Leanchoilia, and non arthropod forms such as Opabinia and Tullimonstrum. The differentiation of the vertebral column of vertebrates and the segments of arthropods are controlled by homologous genes that are expressed in a anterior to posterior sequence. Out of place (ectopic) expression of posterior genes in the anterior region produces posterior features in the antennal field of arthropods and in the most anterior vertebrae of the vertebrates. This potential for conversion of anterior features was present in the shared ancestor of vertebrates and arthropods. Thus evolution of novel anterior features resulting from ectopic expression could occur in both deuterostomes and protostomes and may account for a range of novel fossil forms. This suggests that parallel evolution of unusual anterior features could occur, and the presence of these features may not be the best character to use in a phylogenetic analyses.

scholarly journals Epigenetic Manipulation Facilitates the Generation of Skeletal Muscle Cells from Pluripotent Stem Cells

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Tomohiko Akiyama ◽  
Shunichi Wakabayashi ◽  
Atsumi Soma ◽  
Saeko Sato ◽  
Yuhki Nakatake ◽  
...  
Keyword(s):  
Stem Cells ◽  
Pluripotent Stem Cells ◽  
Myogenic Differentiation ◽  
Ectopic Expression ◽  
Cell Types ◽  
Culture Conditions ◽  
The Body ◽  
Specific Cell ◽  
Modifying Factors

Human pluripotent stem cells (hPSCs) have the capacity to differentiate into essentially all cell types in the body. Such differentiation can be directed to specific cell types by appropriate cell culture conditions or overexpressing lineage-defining transcription factors (TFs). Especially, for the activation of myogenic program, early studies have shown the effectiveness of enforced expression of TFs associated with myogenic differentiation, such as PAX7 and MYOD1. However, the efficiency of direct differentiation was rather low, most likely due to chromatin features unique to hPSCs, which hinder the access of TFs to genes involved in muscle differentiation. Indeed, recent studies have demonstrated that ectopic expression of epigenetic-modifying factors such as a histone demethylase and an ATP-dependent remodeling factor significantly enhances myogenic differentiation from hPSCs. In this article, we review the recent progress for in vitro generation of skeletal muscles from hPSCs through forced epigenetic and transcriptional manipulation.

scholarly journals Small adipose stores in cystic fibrosis mice are characterized by reduced cell volume, not cell number

2018 ◽  
Vol 315 (6) ◽  
pp. G943-G953 ◽  
Author(s):  
Ilya Bederman ◽  
Alex DiScenna ◽  
Leigh Henderson ◽  
Aura Perez ◽  
Jeannie Klavanian ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Adipose Tissue ◽  
Body Mass ◽  
Genetic Disorder ◽  
Clinical Care ◽  
Cell Types ◽  
Cell Number ◽  
The Body ◽  
Clear Understanding ◽  
Organ Systems

Cystic fibrosis (CF) is a lethal genetic disorder that affects many organ systems of the body, including various endocrine and exocrine tissues. Health and survival positively associate with body mass, and as a consequence, CF clinical care includes high-fat, high-calorie diets to maintain and increase adipose tissue stores. Such strategies have been implemented without a clear understanding of the cause and effect relationship between body mass and patients’ health. Here, we used CF mouse models, which display small adipose stores, to begin examining body fat as a prelude into mechanistic studies of low body growth in CF, so that optimal therapeutic strategies could be developed. We reasoned that low adiposity must result from reduced number and/or volume of adipocytes. To determine relative contribution of either mechanism, we quantified volume of intraperitoneal and subcutaneous adipocytes. We found smaller, but not fewer, adipocytes in CF compared with wild-type (WT) animals. Specifically, intraperitoneal CF adipocytes were one-half the volume of WT cells, whereas subcutaneous cells were less affected by the Cftr genotype. No differences were found in cell types between CF and WT adipose tissues. Adipose tissue CFTR mRNA was detected, and we found greater CFTR expression in intraperitoneal depots as compared with subcutaneous samples. RNA sequencing revealed that CF adipose tissue exhibited lower expression of several key genes of adipocyte function ( Lep, Pck1, Fas, Jun), consistent with low triglyceride storage. The data indicate that CF adipocytes contain fewer triglycerides than WT cells, and a role for CFTR in these cells is proposed. NEW & NOTEWORTHY Adipocytes in cystic fibrosis mice exhibit smaller size due to low triglyceride storage. Adipocyte cell number per fat pad is similar, implying triglyceride storage problem. The absence of CFTR function in adipose tissue has been proposed as a direct link to low triglyceride storage in cystic fibrosis.

scholarly journals The hepatocyte clock and feeding control chronophysiology of multiple liver cell types

Science ◽  
2020 ◽  
Vol 369 (6509) ◽  
pp. 1388-1394 ◽  
Author(s):  
Dongyin Guan ◽  
Ying Xiong ◽  
Trang Minh Trinh ◽  
Yang Xiao ◽  
Wenxiang Hu ◽  
...  
Keyword(s):  
De Novo ◽  
Cell Communication ◽  
Cell Types ◽  
The Body ◽  
De Novo Lipogenesis ◽  
Diurnal Rhythms ◽  
Molecular Clocks ◽  
Peripheral Clocks ◽  
Multiple Cell ◽  
Feeding Control

Most cells of the body contain molecular clocks, but the requirement of peripheral clocks for rhythmicity and their effects on physiology are not well understood. We show that deletion of core clock components REV-ERBα and REV-ERBβ in adult mouse hepatocytes disrupts diurnal rhythms of a subset of liver genes and alters the diurnal rhythm of de novo lipogenesis. Liver function is also influenced by nonhepatocytic cells, and the loss of hepatocyte REV-ERBs remodels the rhythmic transcriptomes and metabolomes of multiple cell types within the liver. Finally, alteration of food availability demonstrates the hierarchy of the cell-intrinsic hepatocyte clock mechanism and the feeding environment. Together, these studies reveal previously unsuspected roles of the hepatocyte clock in the physiological coordination of nutritional signals and cell-cell communication controlling rhythmic metabolism.

Perbedaan Efektivitas Pemberian Origami Dan Playdough Terhadap Perkembangan Pada Anak Prasekolah Kelompok A Di TK Aisyiyah Bustanul Athfal Kota Kediri

2019 ◽  
Vol 8 (1) ◽  
Author(s):  
Halimatus Saidah ◽  
Yunida Septiyanty
Keyword(s):  
Child Development ◽  
Sampling Technique ◽  
The Body ◽  
Purposive Sampling ◽  
Organ Systems ◽  
Post Test ◽  
Group A ◽  
Key Words Development ◽  
Children Development ◽  
Research Show

ABSTRAKPerkembangan (development) adalah bertambahnya kemampuan atau fungsi semua sistem organ tubuh sebagai akibat bertambahnya kematangan atau maturitas fungsi sistem organ tubuh (Dewi, 2013). Tujuan penelitian ini adalah mengetahui perbedaan efektivitas pemberian origami dan playdough terhadap perkembangan pada anak prasekolah kelompok A di TK Aisyiyah Bustanul Athfal tahun 2018.Desain penelitian yang digunakan adalah penelitian pre eksperiment dengan pendekatan pre-test and post-test Design. Populasi yang diteliti adalah seluruh anak kelompok A di TK Aisyiyah Bustanul Athfal berjumlah 56 anak dengan teknik purposive sampling diperoleh sampel 36 responden. Instrumen penelitian yang digunakan adalah lembar KPSP. Hasil penelitian kemudian dianalisa dengan menggunakan wilcoxon signed rank.Hasil penelitian yang dilakukan menunjukan bahwa perkembangan anak sebelum pelaksanaan pemberian Origami didapatkan setengahnya perkembangan anak meragukan, setelah pelaksanaan didapatkan hampir seluruhnya perkembangan anak sesuai. Perkembangan anak sebelum pelaksanaan pemberian Playdough didapatkan sebagian besar perkembangan anak meragukan, setelah pelaksanaan didapatkan sebagian besar perkembangan anak sesuai. Hasil analisis menunjukkan ada pengaruh pemberian permainan origami dan permainan Playdough terhadap perkembangan anak kelompok A di TK Aisyiyah Bustanul Athfal Tahun 2018 dengan hasil ρ-value = 0,001 ɑ = 0,05 dari kelompok origami dan ρ-value = 0,007 ɑ = 0,05 dari kelompok playdough, sedangkan hasil analisis perbedaan adanya perbedaan efektivitas pengaruh pemberian permainan origami dan playdough terhadap perkembangan anak pada kelompok A di TK Aisyiyah Bustanul Athfal Tahun 2018 dengan hasil ρ-value = 0,043 ɑ = 0,05.Berdasarkan hasil penelitian dapat disimpulkan ada pengaruh permainan origami dan playdough terhadap perkembangan anak pada kelompok A di TK Aisyiyah Bustanul Athfal Tahun 2018. Diharapkan kepada orang tua maupun guru untuk lebih meningkatkan frekuensi dalam memberi stimulus permainan terutama permainan origami yang diberikan kepada anak. Kata Kunci : Perkembangan , Anak Prasekolah,  Origami, Playdough ABSTRACTDevelopment is increasing ability or function of all organ systems of the body as a result of increasing maturity or maturity function of the organ system of the body (Dewi, 2013). The purpose of this research is to know the effectiveness difference of origami and playdough on development in preschoolers group A in Aisyiyah Bustanul Athfal Kindergarten in 2018.The research design used is research pre eksperiment with approach pre-test dan post-test. The population studied was all group A children in kindergarten Aisyiyah Bustanul Athfal amounted to 56 children with purposive sampling technique obtained sample 36 respondents. The research instrument used is KPSP sheet. The results were then analyzed by using wilcoxon signed rank.The results of the research show that the development of children before the implementation of giving Origami found half of child development doubt, after the implementation is obtained almost entirely the child's development accordingly. Child development prior to the implementation of Playdough gift obtained most of the development of children doubt, after the implementation is obtained most of the child's development accordingly.  The results of the analysis show that there is an effect of giving origami game and Playdough game to the child development group A in Aisyiyah Bustanul Athfal Kindergarten Year 2018 with the result ρ-value = 0.001 ɑ = 0.05 from the origami group and ρ-value = 0.007 ɑ = 0.05 of the playdough group, while the result of difference analysis that is difference between origami and playdough influence to children development in group A diiyah Aisyiyah Bustanul Athfal Year 2018 with result of ρ-value = 0,043 ɑ = 0,05.Based on the research results can be concluded there is influence of origami and playdough on the development of children in group A in Aisyiyah Bustanul Athfal Kindergarten Year 2018. Expected to parents and teachers to increase the frequency of giving stimulus especially the origami given to the child. Key Words : Development, children preschool, Origami, Playdough

Asymmetric Dopaminergic Dysfunction in Brain-First versus Body-First Parkinson’s Disease Subtypes

2021 ◽  
pp. 1-11
Author(s):  
Karoline Knudsen ◽  
Tatyana D. Fedorova ◽  
Jacob Horsager ◽  
Katrine B. Andersen ◽  
Casper Skjærbæk ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
De Novo ◽  
Specific Binding ◽  
Asymmetry Index ◽  
The Body ◽  
Specific Binding Ratio ◽  
Dat Spect ◽  
Vagal Innervation ◽  
Nigrostriatal Degeneration

Background: We have hypothesized that Parkinson’s disease (PD) comprises two subtypes. Brain-first, where pathogenic α-synuclein initially forms unilaterally in one hemisphere leading to asymmetric nigrostriatal degeneration, and body-first with initial enteric pathology, which spreads through overlapping vagal innervation leading to more symmetric brainstem involvement and hence more symmetric nigrostriatal degeneration. Isolated REM sleep behaviour disorder has been identified as a strong marker of the body-first type. Objective: To analyse striatal asymmetry in [18F]FDOPA PET and [123I]FP-CIT DaT SPECT data from iRBD patients, de novo PD patients with RBD (PD +RBD) and de novo PD patients without RBD (PD - RBD). These groups were defined as prodromal body-first, de novo body-first, and de novo brain-first, respectively. Methods: We included [18F]FDOPA PET scans from 21 iRBD patients, 11 de novo PD +RBD, 22 de novo PD - RBD, and 18 controls subjects. Also, [123I]FP-CIT DaT SPECT data from iRBD and de novo PD patients with unknown RBD status from the PPPMI dataset was analysed. Lowest putamen specific binding ratio and putamen asymmetry index (AI) was defined. Results: Nigrostriatal degeneration was significantly more symmetric in patients with RBD versus patients without RBD or with unknown RBD status in both FDOPA (p = 0.001) and DaT SPECT (p = 0.001) datasets. Conclusion: iRBD subjects and de novo PD +RBD patients present with significantly more symmetric nigrostriatal dopaminergic degeneration compared to de novo PD - RBD patients. The results support the hypothesis that body-first PD is characterized by more symmetric distribution most likely due to more symmetric propagation of pathogenic α-synuclein compared to brain-first PD.

scholarly journals De novo TRPV4 Leu619Pro variant causes a new channelopathy characterised by giant cell lesions of the jaws and skull, skeletal abnormalities and polyneuropathy

2021 ◽  
pp. jmedgenet-2020-107427
Author(s):  
Aviel Ragamin ◽  
Carolina C Gomes ◽  
Karen Bindels-de Heus ◽  
Renata Sandoval ◽  
Angelia V Bassenden ◽  
...  
Keyword(s):  
Giant Cell ◽  
De Novo ◽  
Neuromuscular Disorders ◽  
Somatic Mosaicism ◽  
Ion Leakage ◽  
Gain Of Function ◽  
Therapeutic Modalities ◽  
Organ Systems ◽  
Heterozygous Variant ◽  
Systemic Disorder

BackgroundPathogenic germline variants in Transient Receptor Potential Vanilloid 4 Cation Channel (TRPV4) lead to channelopathies, which are phenotypically diverse and heterogeneous disorders grossly divided in neuromuscular disorders and skeletal dysplasia. We recently reported in sporadic giant cell lesions of the jaws (GCLJs) novel, somatic, heterozygous, gain-of-function mutations in TRPV4, at Met713.MethodsHere we report two unrelated women with a de novo germline p.Leu619Pro TRPV4 variant and an overlapping systemic disorder affecting all organs individually described in TRPV4 channelopathies.ResultsFrom an early age, both patients had several lesions of the nervous system including progressive polyneuropathy, and multiple aggressive giant cell-rich lesions of the jaws and craniofacial/skull bones, and other skeletal lesions. One patient had a relatively milder disease phenotype possibly due to postzygotic somatic mosaicism. Indeed, the TRPV4 p.Leu619Pro variant was present at a lower frequency (variant allele frequency (VAF)=21.6%) than expected for a heterozygous variant as seen in the other proband, and showed variable regional frequency in the GCLJ (VAF ranging from 42% to 10%). In silico structural analysis suggests that the gain-of-function p.Leu619Pro alters the ion channel activity leading to constitutive ion leakage.ConclusionOur findings define a novel polysystemic syndrome due to germline TRPV4 p.Leu619Pro and further extend the spectrum of TRPV4 channelopathies. They further highlight the convergence of TRPV4 mutations on different organ systems leading to complex phenotypes which are further mitigated by possible post-zygotic mosaicism. Treatment of this disorder is challenging, and surgical intervention of the GCLJ worsens the lesions, suggesting the future use of MEK inhibitors and TRPV4 antagonists as therapeutic modalities for unmet clinical needs.

scholarly journals Extracellular-Vesicle-Based Coatings Enhance Bioactivity of Titanium Implants—SurfEV

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1445
Author(s):  
Taisa Nogueira Pansani ◽  
Thanh Huyen Phan ◽  
Qingyu Lei ◽  
Alexey Kondyurin ◽  
Bill Kalionis ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Titanium Surface ◽  
Wound Closure ◽  
Cell Types ◽  
Extracellular Vesicle ◽  
Tissue Growth ◽  
Titanium Implants ◽  
The Body ◽  
High Concentrations ◽  
And Migration

Extracellular vesicles (EVs) are nanoparticles released by cells that contain a multitude of biomolecules, which act synergistically to signal multiple cell types. EVs are ideal candidates for promoting tissue growth and regeneration. The tissue regenerative potential of EVs raises the tantalizing possibility that immobilizing EVs on implant surfaces could potentially generate highly bioactive and cell-instructive surfaces that would enhance implant integration into the body. Such surfaces could address a critical limitation of current implants, which do not promote bone tissue formation or bond bone. Here, we developed bioactive titanium surface coatings (SurfEV) using two types of EVs: secreted by decidual mesenchymal stem cells (DEVs) and isolated from fermented papaya fluid (PEVs). For each EV type, we determined the size, morphology, and molecular composition. High concentrations of DEVs enhanced cell proliferation, wound closure, and migration distance of osteoblasts. In contrast, the cell proliferation and wound closure decreased with increasing concentration of PEVs. DEVs enhanced Ca/P deposition on the titanium surface, which suggests improvement in bone bonding ability of the implant (i.e., osteointegration). EVs also increased production of Ca and P by osteoblasts and promoted the deposition of mineral phase, which suggests EVs play key roles in cell mineralization. We also found that DEVs stimulated the secretion of secondary EVs observed by the presence of protruding structures on the cell membrane. We concluded that, by functionalizing implant surfaces with specialized EVs, we will be able to enhance implant osteointegration by improving hydroxyapatite formation directly at the surface and potentially circumvent aseptic loosening of implants.

scholarly journals High-throughput screening of circRNAs reveals novel mechanisms of tuberous sclerosis complex-related renal angiomyolipoma

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Yang Zhao ◽  
Hao Guo ◽  
Wenda Wang ◽  
Guoyang Zheng ◽  
Zhan Wang ◽  
...  
Keyword(s):  
Lipid Metabolism ◽  
Tuberous Sclerosis ◽  
Tuberous Sclerosis Complex ◽  
Regulatory Network ◽  
High Throughput Screening ◽  
Kidney Tissue ◽  
Cell Types ◽  
The Body ◽  
Differentially Expressed ◽  
Renal Angiomyolipoma

Abstract Objective Tuberous sclerosis complex (TSC) is a rare autosomal dominant disease characterized by lesions throughout the body. Our previous study showed the abnormal up-regulation of miRNAs plays an important part in the pathogenesis of TSC-related renal angiomyolipoma (TSC-RAML). circRNAs were known as important regulators of miRNA, but little is known about the circRNAs in TSC-RAMLs. Methods Microarray chips and RNA sequencing were used to identify the circRNAs and mRNAs that were differently expressed between the TSC-RAML and normal kidney tissue. A competitive endogenous RNA (ceRNA) regulatory network was constructed to reveal the regulation of miRNAs and mRNAs by the circRNAs. The biological functions of circRNA and mRNA were analyzed by pathway analysis. Microenvironmental cell types were estimated with the MCP-counter package. Results We identified 491 differentially expressed circRNAs (DECs) and 212 differentially expressed genes (DEGs), and 6 DECs were further confirmed by q-PCR. A ceRNA regulatory network which included 6 DECs, 5 miRNAs, and 63 mRNAs was established. Lipid biosynthetic process was significantly up-regulated in TSC-RAML, and the humoral immune response and the leukocyte chemotaxis pathway were found to be down-regulated. Fibroblasts are enriched in TSC-RAML, and the up-regulation of circRNA_000799 and circRNA_025332 may be significantly correlated to the infiltration of the fibroblasts. Conclusion circRNAs may regulate the lipid metabolism of TSC-RAML by regulation of the miRNAs. Fibroblasts are enriched in TSC-RAMLs, and the population of fibroblast may be related to the alteration of circRNAs of TSC-RAML. Lipid metabolism in fibroblasts is a potential treatment target for TSC-RAML.

scholarly journals Glucocorticoid Receptor β (GRβ): Beyond Its Dominant-Negative Function

2021 ◽  
Vol 22 (7) ◽  
pp. 3649
Author(s):  
Patricia Ramos-Ramírez ◽  
Omar Tliba
Keyword(s):  
Current Knowledge ◽  
Inflammatory Diseases ◽  
Cell Communication ◽  
Cell Types ◽  
The Body ◽  
Dominant Negative ◽  
Negative Effects ◽  
Independent Manner ◽  
Distinct Cell ◽  
Induced Apoptosis

Glucocorticoids (GCs) act via the GC receptor (GR), a receptor ubiquitously expressed in the body where it drives a broad spectrum of responses within distinct cell types and tissues, which vary in strength and specificity. The variability of GR-mediated cell responses is further extended by the existence of GR isoforms, such as GRα and GRβ, generated through alternative splicing mechanisms. While GRα is the classic receptor responsible for GC actions, GRβ has been implicated in the impairment of GRα-mediated activities. Interestingly, in contrast to the popular belief that GRβ actions are restricted to its dominant-negative effects on GRα-mediated responses, GRβ has been shown to have intrinsic activities and “directly” regulates a plethora of genes related to inflammatory process, cell communication, migration, and malignancy, each in a GRα-independent manner. Furthermore, GRβ has been associated with increased cell migration, growth, and reduced sensitivity to GC-induced apoptosis. We will summarize the current knowledge of GRβ-mediated responses, with a focus on the GRα-independent/intrinsic effects of GRβ and the associated non-canonical signaling pathways. Where appropriate, potential links to airway inflammatory diseases will be highlighted.

scholarly journals Congenital Lumbar Hernia in an 8-Month-Old Boy

2021 ◽  
Vol 15 (1) ◽  
pp. 431-435
Author(s):  
Mohamed Mansy ◽  
Mostafa Kotb ◽  
Mohamed Abouheba
Keyword(s):  
Congenital Anomalies ◽  
Lumbar Hernia ◽  
The Body ◽  
Age Group ◽  
Pediatric Age ◽  
Operative Repair ◽  
Pediatric Age Group ◽  
Organ Systems

Congenital lumbar hernias are uncommonly seen in the pediatric age group, with only about 60 cases reported in the literature. It is usually accompanied by a multitude of congenital anomalies involving different organ systems of the body. For instance, it may involve the ribs, spine, muscles, and the kidneys. Herein, we report a case of congenital lumbar hernia in an 8-month-old boy who underwent an operative repair using a mesh with an uneventful outcome.

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