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Sample records for parhyale ultrabithorax recapitulates

  1. Developing Novel Protein-based Materials using Ultrabithorax: Production, Characterization, and Functionalization

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    Huang, Zhao

    2011-12-01

    Compared to 'conventional' materials made from metal, glass, or ceramics, protein-based materials have unique mechanical properties. Furthermore, the morphology, mechanical properties, and functionality of protein-based materials may be optimized via sequence engineering for use in a variety of applications, including textile materials, biosensors, and tissue engineering scaffolds. The development of recombinant DNA technology has enabled the production and engineering of protein-based materials ex vivo. However, harsh production conditions can compromise the mechanical properties of protein-based materials and diminish their ability to incorporate functional proteins. Developing a new generation of protein-based materials is crucial to (i) improve materials assembly conditions, (ii) create novel mechanical properties, and (iii) expand the capacity to carry functional protein/peptide sequences. This thesis describes development of novel protein-based materials using Ultrabithorax, a member of the Hox family of proteins that regulate developmental pathways in Drosophila melanogaster. The experiments presented (i) establish the conditions required for the assembly of Ubx-based materials, (ii) generate a wide range of Ubx morphologies, (iii) examine the mechanical properties of Ubx fibers, (iv) incorporate protein functions to Ubx-based materials via gene fusion, (v) pattern protein functions within the Ubx materials, and (vi) examine the biocompatibility of Ubx materials in vitro. Ubx-based materials assemble at mild conditions compatible with protein folding and activity, which enables Ubx chimeric materials to retain the function of appended proteins in spatial patterns determined by materials assembly. Ubx-based materials also display mechanical properties comparable to existing protein-based materials and demonstrate good biocompatibility with living cells in vitro. Taken together, this research demonstrates the unique features and future potential of novel Ubx

  2. A taxonomic revision helps to clarify differences between the Atlantic invasive Ptilohyale littoralis and the Mediterranean endemic Parhyale plumicornis (Crustacea, Amphipoda

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    Sabrina Lo Brutto

    2018-04-01

    Full Text Available Ptilohyale explorator (formerly Parhyale explorator, described by Arresti (1989, can be considered to be a synonym of west-Atlantic Ptilohyale littoralis (Stimpson, 1853, based on morphological observations of paratypes and specimens recently collected in the type locality of Ptilohyale explorator. The first collections of Ptilohyale littoralis, from the eastern Atlantic were from the port of Rotterdam (The Netherlands in 2009 and later in Wimereux, Opal Coast (France in 2014; however, the synonymy of Ptilohyale explorator with Ptilohyale littoralis backdates to the first European record of Ptilohyale littoralis in 1985 at La Vigne, Bay of Arcachon (France. This indicates that Ptilohyale littoralis has been established along European Atlantic coast for many years. An assessment of the nominal valid species belonging to the genus Ptilohyale was carried out and a comparison between the Atlantic Ptilohyale littoralis and the very similar Mediterranean hyalid species, Parhyale plumicornis, is presented based on morphological features and distribution. Due to the invasive ability of Ptilohyale littoralis, a comparison between the two species is necessary.

  3. Population dynamics of Parhyale hawaiensis (Crustacea: Amphipod) in laboratory culture and life history diferences between laboratory and wild populations = : Dinâmica populacional de Parhyale hawaiensis de uma cultura de laboratório e comparação de historia de vida com uma população natural

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    Bruno Assanuma Burstin

    2016-01-01

    Resumo: Ramos da ecologia, tal como a teoria da história de vida, podem contribuir para a expansão do espectro de atividades da Ecotoxicologia clássica englobando o poder preditivo de alguns dos princípios da ecologia populacional. Este trabalho se propõe a analisar as estratégias demográficas adotadas pelo crustáceo marinho Parhyale hawaiensis mantido em laboratório, descrevendo seu ciclo de vida, fitness reprodutivo e dinâmica populacional através da construção de tabela de vida tempo-espec...

  4. NEVER forget: negative emotional valence enhances recapitulation.

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    Bowen, Holly J; Kark, Sarah M; Kensinger, Elizabeth A

    2017-07-10

    A hallmark feature of episodic memory is that of "mental time travel," whereby an individual feels they have returned to a prior moment in time. Cognitive and behavioral neuroscience methods have revealed a neurobiological counterpart: Successful retrieval often is associated with reactivation of a prior brain state. We review the emerging literature on memory reactivation and recapitulation, and we describe evidence for the effects of emotion on these processes. Based on this review, we propose a new model: Negative Emotional Valence Enhances Recapitulation (NEVER). This model diverges from existing models of emotional memory in three key ways. First, it underscores the effects of emotion during retrieval. Second, it stresses the importance of sensory processing to emotional memory. Third, it emphasizes how emotional valence - whether an event is negative or positive - affects the way that information is remembered. The model specifically proposes that, as compared to positive events, negative events both trigger increased encoding of sensory detail and elicit a closer resemblance between the sensory encoding signature and the sensory retrieval signature. The model also proposes that negative valence enhances the reactivation and storage of sensory details over offline periods, leading to a greater divergence between the sensory recapitulation of negative and positive memories over time. Importantly, the model proposes that these valence-based differences occur even when events are equated for arousal, thus rendering an exclusively arousal-based theory of emotional memory insufficient. We conclude by discussing implications of the model and suggesting directions for future research to test the tenets of the model.

  5. Comparative functional analyses of ultrabithorax reveal multiple steps and paths to diversification of legs in the adaptive radiation of semi-aquatic insects.

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    Khila, Abderrahman; Abouheif, Ehab; Rowe, Locke

    2014-08-01

    Invasion of new ecological habitats is often associated with lineage diversification, yet the genetic changes underlying invasions and radiations are poorly understood. Over 200 million years ago, the semi-aquatic insects invaded water surface from a common terrestrial ancestor and diversified to exploit a wide array of niches. Here, we uncover the changes in regulation and function of the gene Ultrabithorax associated with both the invasion of water surface and the subsequent diversification of the group. In the common ancestor of the semi-aquatic insects, a novel deployment of Ubx protein in the mid-legs increased their length, thereby enhancing their role in water surface walking. In derived lineages that specialize in rowing on the open water, additional changes in the timing of Ubx expression further elongated the mid-legs thereby facilitating their function as oars. In addition, Ubx protein function was selectively reversed to shorten specific rear-leg segments, thereby enabling their function as rudders. These changes in Ubx have generated distinct niche-specialized morphologies that account for the remarkable diversification of the semi-aquatic insects. Therefore, changes in the regulation and function of a key developmental gene may facilitate both the morphological change necessary to transition to novel habitats and fuel subsequent morphological diversification. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  6. Aberrant Recapitulation of Developmental Program: Novel Target in Scleroderma

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    2015-12-01

    AWARD NUMBER: W81XWH-12-1-0472 TITLE: “Aberrant Recapitulation of Developmental Program: Novel Target in Scleroderma ” PRINCIPAL INVESTIGATOR...SUBTITLE Aberrant Recapitulation of Developmental Program: Novel Target in Scleroderma 5a. CONTRACT NUMBER W81XWH-12-1-0472 5b. GRANT NUMBER 5c. PROGRAM...SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION / AVAILABILITY STATEMENT 13. SUPPLEMENTARY NOTES 14. ABSTRACT Fibrosis in scleroderma is associated

  7. Field migration rates of tidal meanders recapitulate fluvial morphodynamics

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    Finotello, Alvise; Lanzoni, Stefano; Ghinassi, Massimiliano; Marani, Marco; Rinaldo, Andrea; D'Alpaos, Andrea

    2018-02-01

    The majority of tidal channels display marked meandering features. Despite their importance in oil-reservoir formation and tidal landscape morphology, questions remain on whether tidal-meander dynamics could be understood in terms of fluvial processes and theory. Key differences suggest otherwise, like the periodic reversal of landscape-forming tidal flows and the widely accepted empirical notion that tidal meanders are stable landscape features, in stark contrast with their migrating fluvial counterparts. On the contrary, here we show that, once properly normalized, observed migration rates of tidal and fluvial meanders are remarkably similar. Key to normalization is the role of tidal channel width that responds to the strong spatial gradients of landscape-forming flow rates and tidal prisms. We find that migration dynamics of tidal meanders agree with nonlinear theories for river meander evolution. Our results challenge the conventional view of tidal channels as stable landscape features and suggest that meandering tidal channels recapitulate many fluvial counterparts owing to large gradients of tidal prisms across meander wavelengths.

  8. Field migration rates of tidal meanders recapitulate fluvial morphodynamics.

    Science.gov (United States)

    Finotello, Alvise; Lanzoni, Stefano; Ghinassi, Massimiliano; Marani, Marco; Rinaldo, Andrea; D'Alpaos, Andrea

    2018-02-13

    The majority of tidal channels display marked meandering features. Despite their importance in oil-reservoir formation and tidal landscape morphology, questions remain on whether tidal-meander dynamics could be understood in terms of fluvial processes and theory. Key differences suggest otherwise, like the periodic reversal of landscape-forming tidal flows and the widely accepted empirical notion that tidal meanders are stable landscape features, in stark contrast with their migrating fluvial counterparts. On the contrary, here we show that, once properly normalized, observed migration rates of tidal and fluvial meanders are remarkably similar. Key to normalization is the role of tidal channel width that responds to the strong spatial gradients of landscape-forming flow rates and tidal prisms. We find that migration dynamics of tidal meanders agree with nonlinear theories for river meander evolution. Our results challenge the conventional view of tidal channels as stable landscape features and suggest that meandering tidal channels recapitulate many fluvial counterparts owing to large gradients of tidal prisms across meander wavelengths. Copyright © 2018 the Author(s). Published by PNAS.

  9. Recapitulating phylogenies using k-mers: from trees to networks.

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    Bernard, Guillaume; Ragan, Mark A; Chan, Cheong Xin

    2016-01-01

    Ernst Haeckel based his landmark Tree of Life on the supposed ontogenic recapitulation of phylogeny, i.e. that successive embryonic stages during the development of an organism re-trace the morphological forms of its ancestors over the course of evolution. Much of this idea has since been discredited. Today, phylogenies are often based on families of molecular sequences. The standard approach starts with a multiple sequence alignment, in which the sequences are arranged relative to each other in a way that maximises a measure of similarity position-by-position along their entire length. A tree (or sometimes a network) is then inferred. Rigorous multiple sequence alignment is computationally demanding, and evolutionary processes that shape the genomes of many microbes (bacteria, archaea and some morphologically simple eukaryotes) can add further complications. In particular, recombination, genome rearrangement and lateral genetic transfer undermine the assumptions that underlie multiple sequence alignment, and imply that a tree-like structure may be too simplistic. Here, using genome sequences of 143 bacterial and archaeal genomes, we construct a network of phylogenetic relatedness based on the number of shared k -mers (subsequences at fixed length k ). Our findings suggest that the network captures not only key aspects of microbial genome evolution as inferred from a tree, but also features that are not treelike. The method is highly scalable, allowing for investigation of genome evolution across a large number of genomes. Instead of using specific regions or sequences from genome sequences, or indeed Haeckel's idea of ontogeny, we argue that genome phylogenies can be inferred using k -mers from whole-genome sequences. Representing these networks dynamically allows biological questions of interest to be formulated and addressed quickly and in a visually intuitive manner.

  10. Generous to a Fault: A Deep, Recapitulative Pattern of Thought in Ricoeur’s Works

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    Joél Z. Schmidt

    2012-12-01

    Full Text Available Paul Ricoeur clearly sought to differentiate between and keep separate his philosophical and theological intellectual endeavors. This essay brings into relief a deep, implicit, recapitulative pattern in Ricoeur’s thinking that cuts across this explicit “conceptual asceticism.” Specifically, it highlights this recapitulative pattern in Ricoeur’s treatment of prophecy in the Hebrew Bible; his understanding of utopia and ideology; the functioning of symbols in The Symbolism of Evil and of sublimation in Freud and Philosophy. On these topics Ricoeur extended his typical generosity toward all that might appear to be outdated, primitive, and even regressive in our collective and personal humanity. The frequently recapitulative nature of Ricoeur’s insights indicates the importance not just of the content of his thought but also the way in which he did his thinking, a pattern which above all was generous, even to a fault. 

  11. A recapitulative three-dimensional model of breast carcinoma requires perfusion for multi-week growth

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    Kayla F Goliwas

    2016-07-01

    Full Text Available Breast carcinomas are complex, three-dimensional tissues composed of cancer epithelial cells and stromal components, including fibroblasts and extracellular matrix. In vitro models that more faithfully recapitulate this dimensionality and stromal microenvironment should more accurately elucidate the processes driving carcinogenesis, tumor progression, and therapeutic response. Herein, novel in vitro breast carcinoma surrogates, distinguished by a relevant dimensionality and stromal microenvironment, are described and characterized. A perfusion bioreactor system was used to deliver medium to surrogates containing engineered microchannels and the effects of perfusion, medium composition, and the method of cell incorporation and density of initial cell seeding on the growth and morphology of surrogates were assessed. Perfused surrogates demonstrated significantly greater cell density and proliferation and were more histologically recapitulative of human breast carcinoma than surrogates maintained without perfusion. Although other parameters of the surrogate system, such as medium composition and cell seeding density, affected cell growth, perfusion was the most influential parameter.

  12. Primary fibroblasts from CSP? mutation carriers recapitulate hallmarks of the adult onset neuronal ceroid lipofuscinosis

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    Benitez, Bruno A.; Sands, Mark S.

    2017-01-01

    Mutations in the co- chaperone protein, CSP?, cause an autosomal dominant, adult-neuronal ceroid lipofuscinosis (AD-ANCL). The current understanding of CSP? function exclusively at the synapse fails to explain the autophagy-lysosome pathway (ALP) dysfunction in cells from AD-ANCL patients. Here, we demonstrate unexpectedly that primary dermal fibroblasts from pre-symptomatic mutation carriers recapitulate in vitro features found in the brains of AD-ANCL patients including auto-fluorescent sto...

  13. Heterotypic mouse models of canine osteosarcoma recapitulate tumor heterogeneity and biological behavior

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    Milcah C. Scott

    2016-12-01

    Full Text Available Osteosarcoma (OS is a heterogeneous and rare disease with a disproportionate impact because it mainly affects children and adolescents. Lamentably, more than half of patients with OS succumb to metastatic disease. Clarification of the etiology of the disease, development of better strategies to manage progression, and methods to guide personalized treatments are among the unmet health needs for OS patients. Progress in managing the disease has been hindered by the extreme heterogeneity of OS; thus, better models that accurately recapitulate the natural heterogeneity of the disease are needed. For this study, we used cell lines derived from two spontaneous canine OS tumors with distinctly different biological behavior (OS-1 and OS-2 for heterotypic in vivo modeling that recapitulates the heterogeneous biology and behavior of this disease. Both cell lines demonstrated stability of the transcriptome when grown as orthotopic xenografts in athymic nude mice. Consistent with the behavior of the original tumors, OS-2 xenografts grew more rapidly at the primary site and had greater propensity to disseminate to lung and establish microscopic metastasis. Moreover, OS-2 promoted formation of a different tumor-associated stromal environment than OS-1 xenografts. OS-2-derived tumors comprised a larger percentage of the xenograft tumors than OS-1-derived tumors. In addition, a robust pro-inflammatory population dominated the stromal cell infiltrates in OS-2 xenografts, whereas a mesenchymal population with a gene signature reflecting myogenic signaling dominated those in the OS-1 xenografts. Our studies show that canine OS cell lines maintain intrinsic features of the tumors from which they were derived and recapitulate the heterogeneous biology and behavior of bone cancer in mouse models. This system provides a resource to understand essential interactions between tumor cells and the stromal environment that drive the progression and metastatic propensity of

  14. Heterotypic mouse models of canine osteosarcoma recapitulate tumor heterogeneity and biological behavior.

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    Scott, Milcah C; Tomiyasu, Hirotaka; Garbe, John R; Cornax, Ingrid; Amaya, Clarissa; O'Sullivan, M Gerard; Subramanian, Subbaya; Bryan, Brad A; Modiano, Jaime F

    2016-12-01

    Osteosarcoma (OS) is a heterogeneous and rare disease with a disproportionate impact because it mainly affects children and adolescents. Lamentably, more than half of patients with OS succumb to metastatic disease. Clarification of the etiology of the disease, development of better strategies to manage progression, and methods to guide personalized treatments are among the unmet health needs for OS patients. Progress in managing the disease has been hindered by the extreme heterogeneity of OS; thus, better models that accurately recapitulate the natural heterogeneity of the disease are needed. For this study, we used cell lines derived from two spontaneous canine OS tumors with distinctly different biological behavior (OS-1 and OS-2) for heterotypic in vivo modeling that recapitulates the heterogeneous biology and behavior of this disease. Both cell lines demonstrated stability of the transcriptome when grown as orthotopic xenografts in athymic nude mice. Consistent with the behavior of the original tumors, OS-2 xenografts grew more rapidly at the primary site and had greater propensity to disseminate to lung and establish microscopic metastasis. Moreover, OS-2 promoted formation of a different tumor-associated stromal environment than OS-1 xenografts. OS-2-derived tumors comprised a larger percentage of the xenograft tumors than OS-1-derived tumors. In addition, a robust pro-inflammatory population dominated the stromal cell infiltrates in OS-2 xenografts, whereas a mesenchymal population with a gene signature reflecting myogenic signaling dominated those in the OS-1 xenografts. Our studies show that canine OS cell lines maintain intrinsic features of the tumors from which they were derived and recapitulate the heterogeneous biology and behavior of bone cancer in mouse models. This system provides a resource to understand essential interactions between tumor cells and the stromal environment that drive the progression and metastatic propensity of OS. © 2016

  15. Multiple congenital malformations of Wolf-Hirschhorn syndrome are recapitulated in Fgfrl1 null mice.

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    Catela, Catarina; Bilbao-Cortes, Daniel; Slonimsky, Esfir; Kratsios, Paschalis; Rosenthal, Nadia; Te Welscher, Pascal

    2009-01-01

    Wolf-Hirschhorn syndrome (WHS) is caused by deletions in the short arm of chromosome 4 (4p) and occurs in about one per 20,000 births. Patients with WHS display a set of highly variable characteristics including craniofacial dysgenesis, mental retardation, speech problems, congenital heart defects, short stature and a variety of skeletal anomalies. Analysis of patients with 4p deletions has identified two WHS critical regions (WHSCRs); however, deletions targeting mouse WHSCRs do not recapitulate the classical WHS defects, and the genes contributing to WHS have not been conclusively established. Recently, the human FGFRL1 gene, encoding a putative fibroblast growth factor (FGF) decoy receptor, has been implicated in the craniofacial phenotype of a WHS patient. Here, we report that targeted deletion of the mouse Fgfrl1 gene recapitulates a broad array of WHS phenotypes, including abnormal craniofacial development, axial and appendicular skeletal anomalies, and congenital heart defects. Fgfrl1 null mutants also display a transient foetal anaemia and a fully penetrant diaphragm defect, causing prenatal and perinatal lethality. Together, these data support a wider role for Fgfrl1 in development, implicate FGFRL1 insufficiency in WHS, and provide a novel animal model to dissect the complex aetiology of this human disease.

  16. Ectopic expression of Msx2 in mammalian myotubes recapitulates aspects of amphibian muscle dedifferentiation

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    Atilgan Yilmaz

    2015-11-01

    Full Text Available In contrast to urodele amphibians and teleost fish, mammals lack the regenerative responses to replace large body parts. Amphibian and fish regeneration uses dedifferentiation, i.e., reversal of differentiated state, as a means to produce progenitor cells to eventually replace damaged tissues. Therefore, induced activation of dedifferentiation responses in mammalian tissues holds an immense promise for regenerative medicine. Here we demonstrate that ectopic expression of Msx2 in cultured mouse myotubes recapitulates several aspects of amphibian muscle dedifferentiation. We found that MSX2, but not MSX1, leads to cellularization of myotubes and downregulates the expression of myotube markers, such as MHC, MRF4 and myogenin. RNA sequencing of myotubes ectopically expressing Msx2 showed downregulation of over 500 myotube-enriched transcripts and upregulation of over 300 myoblast-enriched transcripts. MSX2 selectively downregulated expression of Ptgs2 and Ptger4, two members of the prostaglandin pathway with important roles in myoblast fusion during muscle differentiation. Ectopic expression of Msx2, as well as Msx1, induced partial cell cycle re-entry of myotubes by upregulating CyclinD1 expression but failed to initiate S-phase. Finally, MSX2-induced dedifferentiation in mouse myotubes could be recapitulated by a pharmacological treatment with trichostatin A (TSA, bone morphogenetic protein 4 (BMP4 and fibroblast growth factor 1 (FGF1. Together, these observations indicate that MSX2 is a major driver of dedifferentiation in mammalian muscle cells.

  17. Re-engaging with the past: recapitulation of encoding operations during episodic retrieval

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    Morcom, Alexa M.

    2014-01-01

    Recollection of events is accompanied by selective reactivation of cortical regions which responded to specific sensory and cognitive dimensions of the original events. This reactivation is thought to reflect the reinstatement of stored memory representations and therefore to reflect memory content, but it may also reveal processes which support both encoding and retrieval. The present study used event-related functional magnetic resonance imaging to investigate whether regions selectively engaged in encoding face and scene context with studied words are also re-engaged when the context is later retrieved. As predicted, encoding face and scene context with visually presented words elicited activity in distinct, context-selective regions. Retrieval of face and scene context also re-engaged some of the regions which had shown successful encoding effects. However, this recapitulation of encoding activity did not show the same context selectivity observed at encoding. Successful retrieval of both face and scene context re-engaged regions which had been associated with encoding of the other type of context, as well as those associated with encoding the same type of context. This recapitulation may reflect retrieval attempts which are not context-selective, but use shared retrieval cues to re-engage encoding operations in service of recollection. PMID:24904386

  18. Re-engaging with the past: recapitulation of encoding operations during retrieval

    Directory of Open Access Journals (Sweden)

    Alexa eMorcom

    2014-05-01

    Full Text Available Recollection of events is accompanied by selective reactivation of cortical regions which responded to specific sensory and cognitive dimensions of the original events. This reactivation is thought to reflect the reinstatement of stored memory representations and therefore to reflect memory content, but it may also reveal processes which support both encoding and retrieval. The present study used event-related functional magnetic resonance imaging (fMRI to investigate whether regions selectively engaged in encoding face and scene context with studied words are also re-engaged when the context is later retrieved. As predicted, encoding face and scene context with visually presented words elicited activity in distinct, context-selective regions. Retrieval of face and scene context also re-engaged some of the regions which had shown successful encoding effects. However, this recapitulation of encoding activity did not show the same context selectivity observed at encoding. Successful retrieval of both face and scene context re-engaged regions which had been associated with encoding of the other type of context, as well as those associated with encoding the same type of context. This recapitulation may reflect retrieval attempts which are not context-selective, but use shared retrieval cues to re-engage encoding operations in service of recollection.

  19. Recapitulation of Extracellular LAMININ Environment Maintains Stemness of Satellite Cells In Vitro.

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    Ishii, Kana; Sakurai, Hidetoshi; Suzuki, Nobuharu; Mabuchi, Yo; Sekiya, Ichiro; Sekiguchi, Kiyotoshi; Akazawa, Chihiro

    2018-02-13

    Satellite cells function as precursor cells in mature skeletal muscle homeostasis and regeneration. In healthy tissue, these cells are maintained in a state of quiescence by a microenvironment formed by myofibers and basement membrane in which LAMININs (LMs) form a major component. In the present study, we evaluated the satellite cell microenvironment in vivo and found that these cells are encapsulated by LMα2-5. We sought to recapitulate this satellite cell niche in vitro by culturing satellite cells in the presence of recombinant LM-E8 fragments. We show that treatment with LM-E8 promotes proliferation of satellite cells in an undifferentiated state, through reduced phosphorylation of JNK and p38. On transplantation into injured muscle tissue, satellite cells cultured with LM-E8 promoted the regeneration of skeletal muscle. These findings represent an efficient method of culturing satellite cells for use in transplantation through the recapitulation of the satellite cell niche using recombinant LM-E8 fragments. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Recapitulation of physiological spatiotemporal signals promotes in vitro formation of phenotypically stable human articular cartilage

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    Wei, Yiyong; Zhou, Bin; Bernhard, Jonathan; Robinson, Samuel; Burapachaisri, Aonnicha; Guo, X. Edward

    2017-01-01

    Standard isotropic culture fails to recapitulate the spatiotemporal gradients present during native development. Cartilage grown from human mesenchymal stem cells (hMSCs) is poorly organized and unstable in vivo. We report that human cartilage with physiologic organization and in vivo stability can be grown in vitro from self-assembling hMSCs by implementing spatiotemporal regulation during induction. Self-assembling hMSCs formed cartilage discs in Transwell inserts following isotropic chondrogenic induction with transforming growth factor β to set up a dual-compartment culture. Following a switch in the basal compartment to a hypertrophic regimen with thyroxine, the cartilage discs underwent progressive deep-zone hypertrophy and mineralization. Concurrent chondrogenic induction in the apical compartment enabled the maintenance of functional and hyaline cartilage. Cartilage homeostasis, chondrocyte maturation, and terminal differentiation markers were all up-regulated versus isotropic control groups. We assessed the in vivo stability of the cartilage formed under different induction regimens. Cartilage formed under spatiotemporal regulation in vitro resisted endochondral ossification, retained the expression of cartilage markers, and remained organized following s.c. implantation in immunocompromised mice. In contrast, the isotropic control groups underwent endochondral ossification. Cartilage formed from hMSCs remained stable and organized in vivo. Spatiotemporal regulation during induction in vitro recapitulated some aspects of native cartilage development, and potentiated the maturation of self-assembling hMSCs into stable and organized cartilage resembling the native articular cartilage. PMID:28228529

  1. A hamster model for Marburg virus infection accurately recapitulates Marburg hemorrhagic fever.

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    Marzi, Andrea; Banadyga, Logan; Haddock, Elaine; Thomas, Tina; Shen, Kui; Horne, Eva J; Scott, Dana P; Feldmann, Heinz; Ebihara, Hideki

    2016-12-15

    Marburg virus (MARV), a close relative of Ebola virus, is the causative agent of a severe human disease known as Marburg hemorrhagic fever (MHF). No licensed vaccine or therapeutic exists to treat MHF, and MARV is therefore classified as a Tier 1 select agent and a category A bioterrorism agent. In order to develop countermeasures against this severe disease, animal models that accurately recapitulate human disease are required. Here we describe the development of a novel, uniformly lethal Syrian golden hamster model of MHF using a hamster-adapted MARV variant Angola. Remarkably, this model displayed almost all of the clinical features of MHF seen in humans and non-human primates, including coagulation abnormalities, hemorrhagic manifestations, petechial rash, and a severely dysregulated immune response. This MHF hamster model represents a powerful tool for further dissecting MARV pathogenesis and accelerating the development of effective medical countermeasures against human MHF.

  2. Novel mouse model recapitulates genome and transcriptome alterations in human colorectal carcinomas.

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    McNeil, Nicole E; Padilla-Nash, Hesed M; Buishand, Floryne O; Hue, Yue; Ried, Thomas

    2017-03-01

    Human colorectal carcinomas are defined by a nonrandom distribution of genomic imbalances that are characteristic for this disease. Often, these imbalances affect entire chromosomes. Understanding the role of these aneuploidies for carcinogenesis is of utmost importance. Currently, established transgenic mice do not recapitulate the pathognonomic genome aberration profile of human colorectal carcinomas. We have developed a novel model based on the spontaneous transformation of murine colon epithelial cells. During this process, cells progress through stages of pre-immortalization, immortalization and, finally, transformation, and result in tumors when injected into immunocompromised mice. We analyzed our model for genome and transcriptome alterations using ArrayCGH, spectral karyotyping (SKY), and array based gene expression profiling. ArrayCGH revealed a recurrent pattern of genomic imbalances. These results were confirmed by SKY. Comparing these imbalances with orthologous maps of human chromosomes revealed a remarkable overlap. We observed focal deletions of the tumor suppressor genes Trp53 and Cdkn2a/p16. High-level focal genomic amplification included the locus harboring the oncogene Mdm2, which was confirmed by FISH in the form of double minute chromosomes. Array-based global gene expression revealed distinct differences between the sequential steps of spontaneous transformation. Gene expression changes showed significant similarities with human colorectal carcinomas. Pathways most prominently affected included genes involved in chromosomal instability and in epithelial to mesenchymal transition. Our novel mouse model therefore recapitulates the most prominent genome and transcriptome alterations in human colorectal cancer, and might serve as a valuable tool for understanding the dynamic process of tumorigenesis, and for preclinical drug testing. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Modeling the autistic cell: iPSCs recapitulate developmental principles of syndromic and nonsyndromic ASD.

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    Ben-Reuven, Lihi; Reiner, Orly

    2016-06-01

    The opportunity to model autism spectrum disorders (ASD) through generation of patient-derived induced pluripotent stem cells (iPSCs) is currently an emerging topic. Wide-scale research of altered brain circuits in syndromic ASD, including Rett Syndrome, Fragile X Syndrome, Angelman's Syndrome and sporadic Schizophrenia, was made possible through animal models. However, possibly due to species differences, and to the possible contribution of epigenetics in the pathophysiology of these diseases, animal models fail to recapitulate many aspects of ASD. With the advent of iPSCs technology, 3D cultures of patient-derived cells are being used to study complex neuronal phenotypes, including both syndromic and nonsyndromic ASD. Here, we review recent advances in using iPSCs to study various aspects of the ASD neuropathology, with emphasis on the efforts to create in vitro model systems for syndromic and nonsyndromic ASD. We summarize the main cellular activity phenotypes and aberrant genetic interaction networks that were found in iPSC-derived neurons of syndromic and nonsyndromic autistic patients. © 2016 Japanese Society of Developmental Biologists.

  4. Advanced biomaterials and microengineering technologies to recapitulate the stepwise process of cancer metastasis.

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    Peela, Nitish; Truong, Danh; Saini, Harpinder; Chu, Hunghao; Mashaghi, Samaneh; Ham, Stephanie L; Singh, Sunil; Tavana, Hossein; Mosadegh, Bobak; Nikkhah, Mehdi

    2017-07-01

    Cancer is one of the leading causes of death globally according to the World Health Organization. Although improved treatments and early diagnoses have reduced cancer related mortalities, metastatic disease remains a major clinical challenge. The local tumor microenvironment plays a significant role in cancer metastasis, where tumor cells respond and adapt to a plethora of biochemical and biophysical signals from stromal cells and extracellular matrix (ECM) proteins. Due to these complexities, there is a critical need to understand molecular mechanisms underlying cancer metastasis to facilitate the discovery of more effective therapies. In the past few years, the integration of advanced biomaterials and microengineering approaches has initiated the development of innovative platform technologies for cancer research. These technologies enable the creation of biomimetic in vitro models with physiologically relevant (i.e. in vivo-like) characteristics to conduct studies ranging from fundamental cancer biology to high-throughput drug screening. In this review article, we discuss the biological significance of each step of the metastatic cascade and provide a broad overview on recent progress to recapitulate these stages using advanced biomaterials and microengineered technologies. In each section, we will highlight the advantages and shortcomings of each approach and provide our perspectives on future directions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Recapitulating the Structural Evolution of Redox Regulation in Adenosine 5'-Phosphosulfate Kinase from Cyanobacteria to Plants.

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    Herrmann, Jonathan; Nathin, David; Lee, Soon Goo; Sun, Tony; Jez, Joseph M

    2015-10-09

    In plants, adenosine 5'-phosphosulfate (APS) kinase (APSK) is required for reproductive viability and the production of 3'-phosphoadenosine 5'-phosphosulfate (PAPS) as a sulfur donor in specialized metabolism. Previous studies of the APSK from Arabidopsis thaliana (AtAPSK) identified a regulatory disulfide bond formed between the N-terminal domain (NTD) and a cysteine on the core scaffold. This thiol switch is unique to mosses, gymnosperms, and angiosperms. To understand the structural evolution of redox control of APSK, we investigated the redox-insensitive APSK from the cyanobacterium Synechocystis sp. PCC 6803 (SynAPSK). Crystallographic analysis of SynAPSK in complex with either APS and a non-hydrolyzable ATP analog or APS and sulfate revealed the overall structure of the enzyme, which lacks the NTD found in homologs from mosses and plants. A series of engineered SynAPSK variants reconstructed the structural evolution of the plant APSK. Biochemical analyses of SynAPSK, SynAPSK H23C mutant, SynAPSK fused to the AtAPSK NTD, and the fusion protein with the H23C mutation showed that the addition of the NTD and cysteines recapitulated thiol-based regulation. These results reveal the molecular basis for structural changes leading to the evolution of redox control of APSK in the green lineage from cyanobacteria to plants. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Systematic Three-Dimensional Coculture Rapidly Recapitulates Interactions between Human Neurons and Astrocytes

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    Robert Krencik

    2017-12-01

    Full Text Available Summary: Human astrocytes network with neurons in dynamic ways that are still poorly defined. Our ability to model this relationship is hampered by the lack of relevant and convenient tools to recapitulate this complex interaction. To address this barrier, we have devised efficient coculture systems utilizing 3D organoid-like spheres, termed asteroids, containing pre-differentiated human pluripotent stem cell (hPSC-derived astrocytes (hAstros combined with neurons generated from hPSC-derived neural stem cells (hNeurons or directly induced via Neurogenin 2 overexpression (iNeurons. Our systematic methods rapidly produce structurally complex hAstros and synapses in high-density coculture with iNeurons in precise numbers, allowing for improved studies of neural circuit function, disease modeling, and drug screening. We conclude that these bioengineered neural circuit model systems are reliable and scalable tools to accurately study aspects of human astrocyte-neuron functional properties while being easily accessible for cell-type-specific manipulations and observations. : In this article, Krencik and colleagues show that high-density cocultures of pre-differentiated human astrocytes with induced neurons, from pluripotent stem cells, elicit mature characteristics by 3–5 weeks. This provides a faster and more defined alternative method to organoid cultures for investigating human neural circuit function. Keywords: human pluripotent stem cells, neurons, astrocytes, synapses, coculture, three-dimensional spheres, organoids, disease modeling

  7. Selective Activation of mTORC1 Signaling Recapitulates Microcephaly, Tuberous Sclerosis, and Neurodegenerative Diseases

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    Hidetoshi Kassai

    2014-06-01

    Full Text Available Mammalian target of rapamycin (mTOR has been implicated in human neurological diseases such as tuberous sclerosis complex (TSC, neurodegeneration, and autism. However, little is known about when and how mTOR is involved in the pathogenesis of these diseases, due to a lack of animal models that directly increase mTOR activity. Here, we generated transgenic mice expressing a gain-of-function mutant of mTOR in the forebrain in a temporally controlled manner. Selective activation of mTORC1 in embryonic stages induced cortical atrophy caused by prominent apoptosis of neuronal progenitors, associated with upregulation of HIF-1α. In striking contrast, activation of the mTORC1 pathway in adulthood resulted in cortical hypertrophy with fatal epileptic seizures, recapitulating human TSC. Activated mTORC1 in the adult cortex also promoted rapid accumulation of cytoplasmic inclusions and activation of microglial cells, indicative of progressive neurodegeneration. Our findings demonstrate that mTORC1 plays different roles in developmental and adult stages and contributes to human neurological diseases.

  8. Three-Dimensional Printing Articular Cartilage: Recapitulating the Complexity of Native Tissue.

    Science.gov (United States)

    Guo, Ting; Lembong, Josephine; Zhang, Lijie Grace; Fisher, John P

    2017-06-01

    In the past few decades, the field of tissue engineering combined with rapid prototyping (RP) techniques has been successful in creating biological substitutes that mimic tissues. Its applications in regenerative medicine have drawn efforts in research from various scientific fields, diagnostics, and clinical translation to therapies. While some areas of therapeutics are well developed, such as skin replacement, many others such as cartilage repair can still greatly benefit from tissue engineering and RP due to the low success and/or inefficiency of current existing, often surgical treatments. Through fabrication of complex scaffolds and development of advanced materials, RP provides a new avenue for cartilage repair. Computer-aided design and three-dimensional (3D) printing allow the fabrication of modeled cartilage scaffolds for repair and regeneration of damaged cartilage tissues. Specifically, the various processes of 3D printing will be discussed in details, both cellular and acellular techniques, covering the different materials, geometries, and operational printing conditions for the development of tissue-engineered articular cartilage. Finally, we conclude with some insights on future applications and challenges related to this technology, especially using 3D printing techniques to recapitulate the complexity of native structure for advanced cartilage regeneration.

  9. Substoichiometric hydroxynonenylation of a single protein recapitulates whole-cell-stimulated antioxidant response.

    Science.gov (United States)

    Parvez, Saba; Fu, Yuan; Li, Jiayang; Long, Marcus J C; Lin, Hong-Yu; Lee, Dustin K; Hu, Gene S; Aye, Yimon

    2015-01-14

    Lipid-derived electrophiles (LDEs) that can directly modify proteins have emerged as important small-molecule cues in cellular decision-making. However, because these diffusible LDEs can modify many targets [e.g., >700 cysteines are modified by the well-known LDE 4-hydroxynonenal (HNE)], establishing the functional consequences of LDE modification on individual targets remains devilishly difficult. Whether LDE modifications on a single protein are biologically sufficient to activate discrete redox signaling response downstream also remains untested. Herein, using T-REX (targetable reactive electrophiles and oxidants), an approach aimed at selectively flipping a single redox switch in cells at a precise time, we show that a modest level (∼34%) of HNEylation on a single target is sufficient to elicit the pharmaceutically important antioxidant response element (ARE) activation, and the resultant strength of ARE induction recapitulates that observed from whole-cell electrophilic perturbation. These data provide the first evidence that single-target LDE modifications are important individual events in mammalian physiology.

  10. Comparison of Detailed and Simplified Models of Human Atrial Myocytes to Recapitulate Patient Specific Properties.

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    Daniel M Lombardo

    2016-08-01

    Full Text Available Computer studies are often used to study mechanisms of cardiac arrhythmias, including atrial fibrillation (AF. A crucial component in these studies is the electrophysiological model that describes the membrane potential of myocytes. The models vary from detailed, describing numerous ion channels, to simplified, grouping ionic channels into a minimal set of variables. The parameters of these models, however, are determined across different experiments in varied species. Furthermore, a single set of parameters may not describe variations across patients, and models have rarely been shown to recapitulate critical features of AF in a given patient. In this study we develop physiologically accurate computational human atrial models by fitting parameters of a detailed and of a simplified model to clinical data for five patients undergoing ablation therapy. Parameters were simultaneously fitted to action potential (AP morphology, action potential duration (APD restitution and conduction velocity (CV restitution curves in these patients. For both models, our fitting procedure generated parameter sets that accurately reproduced clinical data, but differed markedly from published sets and between patients, emphasizing the need for patient-specific adjustment. Both models produced two-dimensional spiral wave dynamics for that were similar for each patient. These results show that simplified, computationally efficient models are an attractive choice for simulations of human atrial electrophysiology in spatially extended domains. This study motivates the development and validation of patient-specific model-based mechanistic studies to target therapy.

  11. The developmental programme for genesis of the entire kidney is recapitulated in Wilms tumour

    Science.gov (United States)

    Anaka, Matthew R.; Morison, Ian M.; Reeve, Anthony E.

    2017-01-01

    Wilms tumour (WT) is an embryonal tumour that recapitulates kidney development. The normal kidney is formed from two distinct embryological origins: the metanephric mesenchyme (MM) and the ureteric bud (UB). It is generally accepted that WT arises from precursor cells in the MM; however whether UB-equivalent structures participate in tumorigenesis is uncertain. To address the question of the involvement of UB, we assessed 55 Wilms tumours for the molecular features of MM and UB using gene expression profiling, immunohistochemsitry and immunofluorescence. Expression profiling primarily based on the Genitourinary Molecular Anatomy Project data identified molecular signatures of the UB and collecting duct as well as those of the proximal and distal tubules in the triphasic histology group. We performed immunolabeling for fetal kidneys and WTs. We focused on a central epithelial blastema pattern which is the characteristic of triphasic histology characterized by UB-like epithelial structures surrounded by MM and MM-derived epithelial structures, evoking the induction/aggregation phase of the developing kidney. The UB-like epithelial structures and surrounding MM and epithelial structures resembling early glomerular epithelium, proximal and distal tubules showed similar expression patterns to those of the developing kidney. These observations indicate WTs can arise from a precursor cell capable of generating the entire kidney, such as the cells of the intermediate mesoderm from which both the MM and UB are derived. Moreover, this provides an explanation for the variable histological features of mesenchymal to epithelial differentiation seen in WT. PMID:29040332

  12. Primary fibroblasts from CSPα mutation carriers recapitulate hallmarks of the adult onset neuronal ceroid lipofuscinosis.

    Science.gov (United States)

    Benitez, Bruno A; Sands, Mark S

    2017-07-24

    Mutations in the co- chaperone protein, CSPα, cause an autosomal dominant, adult-neuronal ceroid lipofuscinosis (AD-ANCL). The current understanding of CSPα function exclusively at the synapse fails to explain the autophagy-lysosome pathway (ALP) dysfunction in cells from AD-ANCL patients. Here, we demonstrate unexpectedly that primary dermal fibroblasts from pre-symptomatic mutation carriers recapitulate in vitro features found in the brains of AD-ANCL patients including auto-fluorescent storage material (AFSM) accumulation, CSPα aggregates, increased levels of lysosomal proteins and lysosome enzyme activities. AFSM accumulation correlates with CSPα aggregation and both are susceptible to pharmacological modulation of ALP function. In addition, we demonstrate that endogenous CSPα is present in the lysosome-enriched fractions and co-localizes with lysosome markers in soma, neurites and synaptic boutons. Overexpression of CSPα wild-type (WT) decreases lysotracker signal, secreted lysosomal enzymes and SNAP23-mediated lysosome exocytosis. CSPα WT, mutant and aggregated CSPα are degraded mainly by the ALP but this disease-causing mutation exhibits a faster rate of degradation. Co-expression of both WT and mutant CSPα cause a block in the fusion of autophagosomes/lysosomes. Our data suggest that aggregation-dependent perturbation of ALP function is a relevant pathogenic mechanism for AD-ANCL and supports the use of AFSM or CSPα aggregation as biomarkers for drug screening purposes.

  13. Bioengineered Systems and Designer Matrices That Recapitulate the Intestinal Stem Cell Niche

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    Yuli Wang

    2018-01-01

    Full Text Available The relationship between intestinal stem cells (ISCs and the surrounding niche environment is complex and dynamic. Key factors localized at the base of the crypt are necessary to promote ISC self-renewal and proliferation, to ultimately provide a constant stream of differentiated cells to maintain the epithelial barrier. These factors diminish as epithelial cells divide, migrate away from the crypt base, differentiate into the postmitotic lineages, and end their life span in approximately 7 days when they are sloughed into the intestinal lumen. To facilitate the rapid and complex physiology of ISC-driven epithelial renewal, in vivo gradients of growth factors, extracellular matrix, bacterial products, gases, and stiffness are formed along the crypt-villus axis. New bioengineered tools and platforms are available to recapitulate various gradients and support the stereotypical cellular responses associated with these gradients. Many of these technologies have been paired with primary small intestinal and colonic epithelial cells to re-create select aspects of normal physiology or disease states. These biomimetic platforms are becoming increasingly sophisticated with the rapid discovery of new niche factors and gradients. These advancements are contributing to the development of high-fidelity tissue constructs for basic science applications, drug screening, and personalized medicine applications. Here, we discuss the direct and indirect evidence for many of the important gradients found in vivo and their successful application to date in bioengineered in vitro models, including organ-on-chip and microfluidic culture devices.

  14. Clinical challenges of chronic wounds: searching for an optimal animal model to recapitulate their complexity

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    Robert Nunan

    2014-11-01

    Full Text Available The efficient healing of a skin wound is something that most of us take for granted but is essential for surviving day-to-day knocks and cuts, and is absolutely relied on clinically whenever a patient receives surgical intervention. However, the management of a chronic wound – defined as a barrier defect that has not healed in 3 months – has become a major therapeutic challenge throughout the Western world, and it is a problem that will only escalate with the increasing incidence of conditions that impede wound healing, such as diabetes, obesity and vascular disorders. Despite being clinically and molecularly heterogeneous, all chronic wounds are generally assigned to one of three major clinical categories: leg ulcers, diabetic foot ulcers or pressure ulcers. Although we have gleaned much knowledge about the fundamental cellular and molecular mechanisms that underpin healthy, acute wound healing from various animal models, we have learned much less about chronic wound repair pathology from these models. This might largely be because the animal models being used in this field of research have failed to recapitulate the clinical features of chronic wounds. In this Clinical Puzzle article, we discuss the clinical complexity of chronic wounds and describe the best currently available models for investigating chronic wound pathology. We also assess how such models could be optimised to become more useful tools for uncovering pathological mechanisms and potential therapeutic treatments.

  15. Celiac Disease Histopathology Recapitulates Hedgehog Downregulation, Consistent with Wound Healing Processes Activation.

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    Stefania Senger

    Full Text Available In celiac disease (CD, intestinal epithelium damage occurs secondary to an immune insult and is characterized by blunting of the villi and crypt hyperplasia. Similarities between Hedgehog (Hh/BMP4 downregulation, as reported in a mouse model, and CD histopathology, suggest mechanistic involvement of Hh/BMP4/WNT pathways in proliferation and differentiation of immature epithelial cells in the context of human intestinal homeostasis and regeneration after damage. Herein we examined the nature of intestinal crypt hyperplasia and involvement of Hh/BMP4 in CD histopathology.Immunohistochemistry, qPCR and in situ hybridization were used to study a cohort of 24 healthy controls (HC and 24 patients with diagnosed acute celiac disease (A-CD intestinal biopsies. In A-CD we observed an increase in cells positive for Leucin-rich repeat-containing G protein-coupled receptor 5 (LGR5, an epithelial stem cell specific marker and expansion of WNT responding compartment. Further, we observed alteration in number and distribution of mesenchymal cells, predicted to be part of the intestinal stem cells niche. At the molecular level we found downregulation of indian hedgehog (IHH and other components of the Hh pathway, but we did not observe a concurrent downregulation of BMP4. However, we observed upregulation of BMPs antagonists, gremlin 1 and gremlin 2.Our data suggest that acute CD histopathology partially recapitulates the phenotype reported in Hh knockdown models. Specifically, Hh/BMP4 paradigm appears to be decoupled in CD, as the expansion of the immature cell population does not occur consequent to downregulation of BMP4. Instead, we provide evidence that upregulation of BMP antagonists play a key role in intestinal crypt hyperplasia. This study sheds light on the molecular mechanisms underlying CD histopathology and the limitations in the use of mouse models for celiac disease.

  16. Transgenic Monkey Model of the Polyglutamine Diseases Recapitulating Progressive Neurological Symptoms

    Science.gov (United States)

    Ishibashi, Hidetoshi; Minakawa, Eiko N.; Motohashi, Hideyuki H.; Takayama, Osamu; Popiel, H. Akiko; Puentes, Sandra; Owari, Kensuke; Nakatani, Terumi; Nogami, Naotake; Yamamoto, Kazuhiro; Yonekawa, Takahiro; Tanaka, Yoko; Fujita, Naoko; Suzuki, Hikaru; Aizawa, Shu; Nagano, Seiichi; Yamada, Daisuke; Wada, Keiji; Kohsaka, Shinichi

    2017-01-01

    Abstract Age-associated neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, and the polyglutamine (polyQ) diseases, are becoming prevalent as a consequence of elongation of the human lifespan. Although various rodent models have been developed to study and overcome these diseases, they have limitations in their translational research utility owing to differences from humans in brain structure and function and in drug metabolism. Here, we generated a transgenic marmoset model of the polyQ diseases, showing progressive neurological symptoms including motor impairment. Seven transgenic marmosets were produced by lentiviral introduction of the human ataxin 3 gene with 120 CAG repeats encoding an expanded polyQ stretch. Although all offspring showed no neurological symptoms at birth, three marmosets with higher transgene expression developed neurological symptoms of varying degrees at 3–4 months after birth, followed by gradual decreases in body weight gain, spontaneous activity, and grip strength, indicating time-dependent disease progression. Pathological examinations revealed neurodegeneration and intranuclear polyQ protein inclusions accompanied by gliosis, which recapitulate the neuropathological features of polyQ disease patients. Consistent with neuronal loss in the cerebellum, brain MRI analyses in one living symptomatic marmoset detected enlargement of the fourth ventricle, which suggests cerebellar atrophy. Notably, successful germline transgene transmission was confirmed in the second-generation offspring derived from the symptomatic transgenic marmoset gamete. Because the accumulation of abnormal proteins is a shared pathomechanism among various neurodegenerative diseases, we suggest that this new marmoset model will contribute toward elucidating the pathomechanisms of and developing clinically applicable therapies for neurodegenerative diseases. PMID:28374014

  17. A data-driven weighting scheme for multivariate phenotypic endpoints recapitulates zebrafish developmental cascades

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Guozhu, E-mail: gzhang6@ncsu.edu [Bioinformatics Research Center, North Carolina State University, Raleigh, NC (United States); Roell, Kyle R., E-mail: krroell@ncsu.edu [Bioinformatics Research Center, North Carolina State University, Raleigh, NC (United States); Truong, Lisa, E-mail: lisa.truong@oregonstate.edu [Department of Environmental and Molecular Toxicology, Sinnhuber Aquatic Research Laboratory, Oregon State University, Corvallis, OR (United States); Tanguay, Robert L., E-mail: robert.tanguay@oregonstate.edu [Department of Environmental and Molecular Toxicology, Sinnhuber Aquatic Research Laboratory, Oregon State University, Corvallis, OR (United States); Reif, David M., E-mail: dmreif@ncsu.edu [Bioinformatics Research Center, North Carolina State University, Raleigh, NC (United States); Department of Biological Sciences, Center for Human Health and the Environment, North Carolina State University, Raleigh, NC (United States)

    2017-01-01

    Zebrafish have become a key alternative model for studying health effects of environmental stressors, partly due to their genetic similarity to humans, fast generation time, and the efficiency of generating high-dimensional systematic data. Studies aiming to characterize adverse health effects in zebrafish typically include several phenotypic measurements (endpoints). While there is a solid biomedical basis for capturing a comprehensive set of endpoints, making summary judgments regarding health effects requires thoughtful integration across endpoints. Here, we introduce a Bayesian method to quantify the informativeness of 17 distinct zebrafish endpoints as a data-driven weighting scheme for a multi-endpoint summary measure, called weighted Aggregate Entropy (wAggE). We implement wAggE using high-throughput screening (HTS) data from zebrafish exposed to five concentrations of all 1060 ToxCast chemicals. Our results show that our empirical weighting scheme provides better performance in terms of the Receiver Operating Characteristic (ROC) curve for identifying significant morphological effects and improves robustness over traditional curve-fitting approaches. From a biological perspective, our results suggest that developmental cascade effects triggered by chemical exposure can be recapitulated by analyzing the relationships among endpoints. Thus, wAggE offers a powerful approach for analysis of multivariate phenotypes that can reveal underlying etiological processes. - Highlights: • Introduced a data-driven weighting scheme for multiple phenotypic endpoints. • Weighted Aggregate Entropy (wAggE) implies differential importance of endpoints. • Endpoint relationships reveal developmental cascade effects triggered by exposure. • wAggE is generalizable to multi-endpoint data of different shapes and scales.

  18. Mek1Y130C mice recapitulate aspects of human cardio-facio-cutaneous syndrome

    Science.gov (United States)

    Aoidi, Rifdat; Houde, Nicolas; Landry-Truchon, Kim; Holter, Michael; Jacquet, Kevin; Charron, Louis; Yu, Benjamin D.; Rauen, Katherine A.; Bisson, Nicolas; Newbern, Jason

    2018-01-01

    ABSTRACT The RAS/MAPK signaling pathway is one of the most investigated pathways, owing to its established role in numerous cellular processes and implication in cancer. Germline mutations in genes encoding members of the RAS/MAPK pathway also cause severe developmental syndromes collectively known as RASopathies. These syndromes share overlapping characteristics, including craniofacial dysmorphology, cardiac malformations, cutaneous abnormalities and developmental delay. Cardio-facio-cutaneous syndrome (CFC) is a rare RASopathy associated with mutations in BRAF, KRAS, MEK1 (MAP2K1) and MEK2 (MAP2K2). MEK1 and MEK2 mutations are found in ∼25% of the CFC patients and the MEK1Y130C substitution is the most common one. However, little is known about the origins and mechanisms responsible for the development of CFC. To our knowledge, no mouse model carrying RASopathy-linked Mek1 or Mek2 gene mutations has been reported. To investigate the molecular and developmental consequences of the Mek1Y130C mutation, we generated a mouse line carrying this mutation. Analysis of mice from a Mek1 allelic series revealed that the Mek1Y130C allele expresses both wild-type and Y130C mutant forms of MEK1. However, despite reduced levels of MEK1 protein and the lower abundance of MEK1 Y130C protein than wild type, Mek1Y130C mutants showed increased ERK (MAPK) protein activation in response to growth factors, supporting a role for MEK1 Y130C in hyperactivation of the RAS/MAPK pathway, leading to CFC. Mek1Y130C mutant mice exhibited pulmonary artery stenosis, cranial dysmorphia and neurological anomalies, including increased numbers of GFAP+ astrocytes and Olig2+ oligodendrocytes in regions of the cerebral cortex. These data indicate that the Mek1Y130C mutation recapitulates major aspects of CFC, providing a new animal model to investigate the physiopathology of this RASopathy. This article has an associated First Person interview with the first author of the paper. PMID:29590634

  19. Control of oxygen tension recapitulates zone-specific functions in human liver microphysiology systems.

    Science.gov (United States)

    Lee-Montiel, Felipe T; George, Subin M; Gough, Albert H; Sharma, Anup D; Wu, Juanfang; DeBiasio, Richard; Vernetti, Lawrence A; Taylor, D Lansing

    2017-10-01

    developed and present a method for computationally modeling and measuring oxygen that can easily be implemented in all MPS models. We have applied this method in a liver MPS in which we are then able to control oxygenation in separate devices and demonstrate that zonation-dependent hepatocyte functions in the MPS recapitulate what is known about in vivo liver physiology. We believe that this advance allows a deep experimental investigation on the role of zonation in liver metabolism and disease. In addition, modeling and measuring oxygen tension will be required as investigators migrate from PDMS to plastic and glass devices.

  20. The Progressive BSSG Rat Model of Parkinson's: Recapitulating Multiple Key Features of the Human Disease.

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    Jackalina M Van Kampen

    Full Text Available The development of effective neuroprotective therapies for Parkinson's disease (PD has been severely hindered by the notable lack of an appropriate animal model for preclinical screening. Indeed, most models currently available are either acute in nature or fail to recapitulate all characteristic features of the disease. Here, we present a novel progressive model of PD, with behavioural and cellular features that closely approximate those observed in patients. Chronic exposure to dietary phytosterol glucosides has been found to be neurotoxic. When fed to rats, β-sitosterol β-d-glucoside (BSSG triggers the progressive development of parkinsonism, with clinical signs and histopathology beginning to appear following cessation of exposure to the neurotoxic insult and continuing to develop over several months. Here, we characterize the progressive nature of this model, its non-motor features, the anatomical spread of synucleinopathy, and response to levodopa administration. In Sprague Dawley rats, chronic BSSG feeding for 4 months triggered the progressive development of a parkinsonian phenotype and pathological events that evolved slowly over time, with neuronal loss beginning only after toxin exposure was terminated. At approximately 3 months following initiation of BSSG exposure, animals displayed the early emergence of an olfactory deficit, in the absence of significant dopaminergic nigral cell loss or locomotor deficits. Locomotor deficits developed gradually over time, initially appearing as locomotor asymmetry and developing into akinesia/bradykinesia, which was reversed by levodopa treatment. Late-stage cognitive impairment was observed in the form of spatial working memory deficits, as assessed by the radial arm maze. In addition to the progressive loss of TH+ cells in the substantia nigra, the appearance of proteinase K-resistant intracellular α-synuclein aggregates was also observed to develop progressively, appearing first in the

  1. Ferrets Infected with Bundibugyo Virus or Ebola Virus Recapitulate Important Aspects of Human Filovirus Disease.

    Science.gov (United States)

    Kozak, Robert; He, Shihua; Kroeker, Andrea; de La Vega, Marc-Antoine; Audet, Jonathan; Wong, Gary; Urfano, Chantel; Antonation, Kym; Embury-Hyatt, Carissa; Kobinger, Gary P; Qiu, Xiangguo

    2016-10-15

    Bundibugyo virus (BDBV) is the etiological agent of a severe hemorrhagic fever in humans with a case-fatality rate ranging from 25 to 36%. Despite having been known to the scientific and medical communities for almost 1 decade, there is a dearth of studies on this pathogen due to the lack of a small animal model. Domestic ferrets are commonly used to study other RNA viruses, including members of the order Mononegavirales To investigate whether ferrets were susceptible to filovirus infections, ferrets were challenged with a clinical isolate of BDBV. Animals became viremic within 4 days and succumbed to infection between 8 and 9 days, and a petechial rash was observed with moribund ferrets. Furthermore, several hallmarks of human filoviral disease were recapitulated in the ferret model, including substantial decreases in lymphocyte and platelet counts and dysregulation of key biochemical markers related to hepatic/renal function, as well as coagulation abnormalities. Virological, histopathological, and immunohistochemical analyses confirmed uncontrolled BDBV replication in the major organs. Ferrets were also infected with Ebola virus (EBOV) to confirm their susceptibility to another filovirus species and to potentially establish a virus transmission model. Similar to what was seen with BDBV, important hallmarks of human filoviral disease were observed in EBOV-infected ferrets. This study demonstrates the potential of this small animal model for studying BDBV and EBOV using wild-type isolates and will accelerate efforts to understand filovirus pathogenesis and transmission as well as the development of specific vaccines and antivirals. The 2013-2016 outbreak of Ebola virus in West Africa has highlighted the threat posed by filoviruses to global public health. Bundibugyo virus (BDBV) is a member of the genus Ebolavirus and has caused outbreaks in the past but is relatively understudied, likely due to the lack of a suitable small animal model. Such a model for BDBV is

  2. Auditory Tones and Foot-Shock Recapitulate Spontaneous Sub-Threshold Activity in Basolateral Amygdala Principal Neurons and Interneurons.

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    François Windels

    Full Text Available In quiescent states such as anesthesia and slow wave sleep, cortical networks show slow rhythmic synchronized activity. In sensory cortices this rhythmic activity shows a stereotypical pattern that is recapitulated by stimulation of the appropriate sensory modality. The amygdala receives sensory input from a variety of sources, and in anesthetized animals, neurons in the basolateral amygdala (BLA show slow rhythmic synchronized activity. Extracellular field potential recordings show that these oscillations are synchronized with sensory cortex and the thalamus, with both the thalamus and cortex leading the BLA. Using whole-cell recording in vivo we show that the membrane potential of principal neurons spontaneously oscillates between up- and down-states. Footshock and auditory stimulation delivered during down-states evokes an up-state that fully recapitulates those occurring spontaneously. These results suggest that neurons in the BLA receive convergent input from networks of cortical neurons with slow oscillatory activity and that somatosensory and auditory stimulation can trigger activity in these same networks.

  3. Targeting Hypoxia-Inducible Factor 1α in a New Orthotopic Model of Glioblastoma Recapitulating the Hypoxic Tumor Microenvironment.

    Science.gov (United States)

    Nigim, Fares; Cavanaugh, Jill; Patel, Anoop P; Curry, William T; Esaki, Shin-ichi; Kasper, Ekkehard M; Chi, Andrew S; Louis, David N; Martuza, Robert L; Rabkin, Samuel D; Wakimoto, Hiroaki

    2015-07-01

    Tissue hypoxia and necrosis represent pathophysiologic and histologic hallmarks of glioblastoma (GBM). Although hypoxia inducible factor 1α (HIF-1α) plays crucial roles in the malignant phenotypes of GBM, developing HIF-1α-targeted agents has been hampered by the lack of a suitable preclinical model that recapitulates the complex biology of clinical GBM. We present a new GBM model, MGG123, which was established from a recurrent human GBM. Orthotopic xenografting of stem-like MGG123 cells reproducibly generated lethal tumors that were characterized by foci of palisading necrosis, hypervascularity, and robust stem cell marker expression. Perinecrotic neoplastic cells distinctively express HIF-1α and are proliferative in both xenografts and the patient tissue. The xenografts contain scattered hypoxic foci that were consistently greater than 50 μm distant from blood vessels, indicating intratumoral heterogeneity of oxygenation. Hypoxia enhanced HIF-1α expression in cultured MGG123 cells, which was abrogated by the HIF-1α inhibitors digoxin or ouabain. In vivo, treatment of orthotopic MGG123 xenografts with digoxin decreased HIF-1α expression, vascular endothelial growth factor mRNA levels, and CD34-positive vasculature within the tumors, and extended survival of mice bearing the aggressive MGG123 GBM. This preclinical tumor model faithfully recapitulates the GBM-relevant hypoxic microenvironment and stemness and is a suitable platform for studying disease biology and developing hypoxia-targeted agents.

  4. Recapitulation of Clinical Individual Susceptibility to Drug-Induced QT Prolongation in Healthy Subjects Using iPSC-Derived Cardiomyocytes

    Directory of Open Access Journals (Sweden)

    Tadahiro Shinozawa

    2017-02-01

    Full Text Available To predict drug-induced serious adverse events (SAE in clinical trials, a model using a panel of cells derived from human induced pluripotent stem cells (hiPSCs of individuals with different susceptibilities could facilitate major advancements in translational research in terms of safety and pharmaco-economics. However, it is unclear whether hiPSC-derived cells can recapitulate interindividual differences in drug-induced SAE susceptibility in populations not having genetic disorders such as healthy subjects. Here, we evaluated individual differences in SAE susceptibility based on an in vitro model using hiPSC-derived cardiomyocytes (hiPSC-CMs as a pilot study. hiPSCs were generated from blood samples of ten healthy volunteers with different susceptibilities to moxifloxacin (Mox-induced QT prolongation. Different Mox-induced field potential duration (FPD prolongation values were observed in the hiPSC-CMs from each individual. Interestingly, the QT interval was significantly positively correlated with FPD at clinically relevant concentrations (r > 0.66 in multiple analyses including concentration-QT analysis. Genomic analysis showed no interindividual significant differences in known target-binding sites for Mox and other drugs such as the hERG channel subunit, and baseline QT ranges were normal. The results suggest that hiPSC-CMs from healthy subjects recapitulate susceptibility to Mox-induced QT prolongation and provide proof of concept for in vitro preclinical trials.

  5. Negative regulation of Ultrabithorax expression by engrailed is ...

    Indian Academy of Sciences (India)

    1Present address: European Molecular Biology Laboratory, Heidelberg, Germany. Abstract. In both ... Journal of Genetics, Vol. 79, No. ... Here we present results of a detailed study on the exact nature of ...... Academic Press, San Diego.

  6. A Novel Letrozole Model Recapitulates Both the Reproductive and Metabolic Phenotypes of Polycystic Ovary Syndrome in Female Mice1

    Science.gov (United States)

    Kauffman, Alexander S.; Thackray, Varykina G.; Ryan, Genevieve E.; Tolson, Kristen P.; Glidewell-Kenney, Christine A.; Semaan, Sheila J.; Poling, Matthew C.; Iwata, Nahoko; Breen, Kellie M.; Duleba, Antoni J.; Stener-Victorin, Elisabet; Shimasaki, Shunichi; Webster, Nicholas J.; Mellon, Pamela L.

    2015-01-01

    Polycystic ovary syndrome (PCOS) pathophysiology is poorly understood, due partly to lack of PCOS animal models fully recapitulating this complex disorder. Recently, a PCOS rat model using letrozole (LET), a nonsteroidal aromatase inhibitor, mimicked multiple PCOS phenotypes, including metabolic features absent in other models. Given the advantages of using genetic and transgenic mouse models, we investigated whether LET produces a similar PCOS phenotype in mice. Pubertal female C57BL/6N mice were treated for 5 wk with LET, which resulted in increased serum testosterone and normal diestrus levels of estradiol, similar to the hyperandrogenemia and follicular phase estrogen levels of PCOS women. As in PCOS, ovaries from LET mice were larger, polycystic, and lacked corpora lutea versus controls. Most LET females were acyclic, and all were infertile. LET females displayed elevated serum LH levels and higher Lhb mRNA in the pituitary. In contrast, serum FSH and Fshb were significantly reduced in LET females, demonstrating differential effects on gonadotropins, as in PCOS. Within the ovary, LET females had higher Cyp17, Cyp19, and Fsh receptor mRNA expression. In the hypothalamus, LET females had higher kisspeptin receptor mRNA expression but lower progesterone receptor mRNA levels. LET females also gained more weight than controls, had increased abdominal adiposity and adipocyte size, elevated adipose inflammatory mRNA levels, and impaired glucose tolerance, mirroring the metabolic phenotype in PCOS women. This is the first report of a LET paradigm in mice that recapitulates both reproductive and metabolic PCOS phenotypes and will be useful to genetically probe the PCOS condition. PMID:26203175

  7. A Human Neural Crest Stem Cell-Derived Dopaminergic Neuronal Model Recapitulates Biochemical Abnormalities in GBA1 Mutation Carriers

    Directory of Open Access Journals (Sweden)

    Shi-Yu Yang

    2017-03-01

    Full Text Available Numerically the most important risk factor for the development of Parkinson's disease (PD is the presence of mutations in the glucocerebrosidase GBA1 gene. In vitro and in vivo studies show that GBA1 mutations reduce glucocerebrosidase (GCase activity and are associated with increased α-synuclein levels, reflecting similar changes seen in idiopathic PD brain. We have developed a neural crest stem cell-derived dopaminergic neuronal model that recapitulates biochemical abnormalities in GBA1 mutation-associated PD. Cells showed reduced GCase protein and activity, impaired macroautophagy, and increased α-synuclein levels. Advantages of this approach include easy access to stem cells, no requirement to reprogram, and retention of the intact host genome. Treatment with a GCase chaperone increased GCase protein levels and activity, rescued the autophagic defects, and decreased α-synuclein levels. These results provide the basis for further investigation of GCase chaperones or similar drugs to slow the progression of PD.

  8. Recapitulating cortical development with organoid culture in vitro and modeling abnormal spindle-like (ASPM related primary) microcephaly disease

    Institute of Scientific and Technical Information of China (English)

    Rui Li; Le Sun; Ai Fang; Peng Li; Qian Wu; Xiaoqun Wang

    2017-01-01

    The development of a cerebral organoid culture in vitro offers an opportunity to generate human brain-like organs to investigate mechanisms of human disease that are specific to the neurogenesis of radial glial (RG) and outer radial glial (oRG) cells in the ventricular zone (VZ) and subventricular zone (SVZ) of the developing neocortex.Modeling neuronal progenitors and the organization that produces mature subcortical neuron subtypes during early stages of development is essential for studying human brain developmental diseases.Several previous efforts have shown to grow neural organoid in culture dishes successfully,however we demonstrate a new paradigm that recapitulates neocortical development process with VZ,OSVZ formation and the lamination organization of cortical layer structure.In addition,using patient-specific induced pluripotent stem cells (iPSCs) with dysfunction of the Aspm gene from a primary microcephaly patient,we demonstrate neurogenesis defects result in defective neuronal activity in patient organoids,suggesting a new strategy to study human developmental diseases in central nerve system.

  9. Recapitulating the Structural Evolution of Redox Regulation in Adenosine 5′-Phosphosulfate Kinase from Cyanobacteria to Plants*

    Science.gov (United States)

    Herrmann, Jonathan; Nathin, David; Lee, Soon Goo; Sun, Tony; Jez, Joseph M.

    2015-01-01

    In plants, adenosine 5′-phosphosulfate (APS) kinase (APSK) is required for reproductive viability and the production of 3′-phosphoadenosine 5′-phosphosulfate (PAPS) as a sulfur donor in specialized metabolism. Previous studies of the APSK from Arabidopsis thaliana (AtAPSK) identified a regulatory disulfide bond formed between the N-terminal domain (NTD) and a cysteine on the core scaffold. This thiol switch is unique to mosses, gymnosperms, and angiosperms. To understand the structural evolution of redox control of APSK, we investigated the redox-insensitive APSK from the cyanobacterium Synechocystis sp. PCC 6803 (SynAPSK). Crystallographic analysis of SynAPSK in complex with either APS and a non-hydrolyzable ATP analog or APS and sulfate revealed the overall structure of the enzyme, which lacks the NTD found in homologs from mosses and plants. A series of engineered SynAPSK variants reconstructed the structural evolution of the plant APSK. Biochemical analyses of SynAPSK, SynAPSK H23C mutant, SynAPSK fused to the AtAPSK NTD, and the fusion protein with the H23C mutation showed that the addition of the NTD and cysteines recapitulated thiol-based regulation. These results reveal the molecular basis for structural changes leading to the evolution of redox control of APSK in the green lineage from cyanobacteria to plants. PMID:26294763

  10. Engineering strategies to recapitulate epithelial morphogenesis within synthetic three-dimensional extracellular matrix with tunable mechanical properties

    International Nuclear Information System (INIS)

    Miroshnikova, Y A; Sarang-Sieminski, A L; Jorgens, D M; Auer, M; Spirio, L; Weaver, V M

    2011-01-01

    The mechanical properties (e.g. stiffness) of the extracellular matrix (ECM) influence cell fate and tissue morphogenesis and contribute to disease progression. Nevertheless, our understanding of the mechanisms by which ECM rigidity modulates cell behavior and fate remains rudimentary. To address this issue, a number of two and three-dimensional (3D) hydrogel systems have been used to explore the effects of the mechanical properties of the ECM on cell behavior. Unfortunately, many of these systems have limited application because fiber architecture, adhesiveness and/or pore size often change in parallel when gel elasticity is varied. Here we describe the use of ECM-adsorbed, synthetic, self-assembling peptide (SAP) gels that are able to recapitulate normal epithelial acini morphogenesis and gene expression in a 3D context. By exploiting the range of viscoelasticity attainable with these SAP gels, and their ability to recreate native-like ECM fibril topology with minimal variability in ligand density and pore size, we were able to reconstitute normal and tumor-like phenotypes and gene expression patterns in nonmalignant mammary epithelial cells. Accordingly, this SAP hydrogel system presents the first tunable system capable of independently assessing the interplay between ECM stiffness and multi-cellular epithelial phenotype in a 3D context

  11. Modelling the tumour microenvironment in long-term microencapsulated 3D co-cultures recapitulates phenotypic features of disease progression.

    Science.gov (United States)

    Estrada, Marta F; Rebelo, Sofia P; Davies, Emma J; Pinto, Marta T; Pereira, Hugo; Santo, Vítor E; Smalley, Matthew J; Barry, Simon T; Gualda, Emilio J; Alves, Paula M; Anderson, Elizabeth; Brito, Catarina

    2016-02-01

    3D cell tumour models are generated mainly in non-scalable culture systems, using bioactive scaffolds. Many of these models fail to reflect the complex tumour microenvironment and do not allow long-term monitoring of tumour progression. To overcome these limitations, we have combined alginate microencapsulation with agitation-based culture systems, to recapitulate and monitor key aspects of the tumour microenvironment and disease progression. Aggregates of MCF-7 breast cancer cells were microencapsulated in alginate, either alone or in combination with human fibroblasts, then cultured for 15 days. In co-cultures, the fibroblasts arranged themselves around the tumour aggregates creating distinct epithelial and stromal compartments. The presence of fibroblasts resulted in secretion of pro-inflammatory cytokines and deposition of collagen in the stromal compartment. Tumour cells established cell-cell contacts and polarised around small lumina in the interior of the aggregates. Over the culture period, there was a reduction in oestrogen receptor and membranous E-cadherin alongside loss of cell polarity, increased collective cell migration and enhanced angiogenic potential in co-cultures. These phenotypic alterations, typical of advanced stages of cancer, were not observed in the mono-cultures of MCF-7 cells. The proposed model system constitutes a new tool to study tumour-stroma crosstalk, disease progression and drug resistance mechanisms. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. In vitro recapitulation of the urea cycle using murine embryonic stem cell-derived in vitro liver model.

    Science.gov (United States)

    Tamai, Miho; Aoki, Mami; Nishimura, Akihito; Morishita, Koji; Tagawa, Yoh-ichi

    2013-12-01

    Ammonia, a toxic metabolite, is converted to urea in hepatocytes via the urea cycle, a process necessary for cell/organismal survival. In liver, hepatocytes, polygonal and multipolar structures, have a few sides which face hepatic sinusoids and adjacent hepatocytes to form intercellular bile canaliculi connecting to the ductules. The critical nature of this three-dimensional environment should be related to the maintenance of hepatocyte function such as urea synthesis. Recently, we established an in vitro liver model derived from murine embryonic stem cells, IVL(mES), which included the hepatocyte layer and a surrounding sinusoid vascular-like network. The IVL(mES) culture, where the hepatocyte is polarized in a similar fashion to its in vivo counterpart, could successfully recapitulate in vivo results. L-Ornithine is an intermediate of the urea cycle, but supplemental L-ornithine does not activate the urea cycle in the apolar primary hepatocyte of monolayer culture. In the IVL(mES), supplemental L-ornithine could activate the urea cycle, and also protect against ammonium/alcohol-induced hepatocyte death. While the IVL(mES) displays architectural and functional properties similar to the liver, primary hepatocyte of monolayer culture fail to model critical functional aspects of liver physiology. We propose that the IVL(mES) will represent a useful, humane alternative to animal studies for drug toxicity and mechanistic studies of liver injury.

  13. Host-Specific Parvovirus Evolution in Nature Is Recapitulated by In Vitro Adaptation to Different Carnivore Species

    Science.gov (United States)

    Allison, Andrew B.; Kohler, Dennis J.; Ortega, Alicia; Hoover, Elizabeth A.; Grove, Daniel M.; Holmes, Edward C.; Parrish, Colin R.

    2014-01-01

    Canine parvovirus (CPV) emerged as a new pandemic pathogen of dogs in the 1970s and is closely related to feline panleukopenia virus (FPV), a parvovirus of cats and related carnivores. Although both viruses have wide host ranges, analysis of viral sequences recovered from different wild carnivore species, as shown here, demonstrated that >95% were derived from CPV-like viruses, suggesting that CPV is dominant in sylvatic cycles. Many viral sequences showed host-specific mutations in their capsid proteins, which were often close to sites known to control binding to the transferrin receptor (TfR), the host receptor for these carnivore parvoviruses, and which exhibited frequent parallel evolution. To further examine the process of host adaptation, we passaged parvoviruses with alternative backgrounds in cells from different carnivore hosts. Specific mutations were selected in several viruses and these differed depending on both the background of the virus and the host cells in which they were passaged. Strikingly, these in vitro mutations recapitulated many specific changes seen in viruses from natural populations, strongly suggesting they are host adaptive, and which were shown to result in fitness advantages over their parental virus. Comparison of the sequences of the transferrin receptors of the different carnivore species demonstrated that many mutations occurred in and around the apical domain where the virus binds, indicating that viral variants were likely selected through their fit to receptor structures. Some of the viruses accumulated high levels of variation upon passage in alternative hosts, while others could infect multiple different hosts with no or only a few additional mutations. Overall, these studies demonstrate that the evolutionary history of a virus, including how long it has been circulating and in which hosts, as well as its phylogenetic background, has a profound effect on determining viral host range. PMID:25375184

  14. Host-specific parvovirus evolution in nature is recapitulated by in vitro adaptation to different carnivore species.

    Directory of Open Access Journals (Sweden)

    Andrew B Allison

    2014-11-01

    Full Text Available Canine parvovirus (CPV emerged as a new pandemic pathogen of dogs in the 1970s and is closely related to feline panleukopenia virus (FPV, a parvovirus of cats and related carnivores. Although both viruses have wide host ranges, analysis of viral sequences recovered from different wild carnivore species, as shown here, demonstrated that>95% were derived from CPV-like viruses, suggesting that CPV is dominant in sylvatic cycles. Many viral sequences showed host-specific mutations in their capsid proteins, which were often close to sites known to control binding to the transferrin receptor (TfR, the host receptor for these carnivore parvoviruses, and which exhibited frequent parallel evolution. To further examine the process of host adaptation, we passaged parvoviruses with alternative backgrounds in cells from different carnivore hosts. Specific mutations were selected in several viruses and these differed depending on both the background of the virus and the host cells in which they were passaged. Strikingly, these in vitro mutations recapitulated many specific changes seen in viruses from natural populations, strongly suggesting they are host adaptive, and which were shown to result in fitness advantages over their parental virus. Comparison of the sequences of the transferrin receptors of the different carnivore species demonstrated that many mutations occurred in and around the apical domain where the virus binds, indicating that viral variants were likely selected through their fit to receptor structures. Some of the viruses accumulated high levels of variation upon passage in alternative hosts, while others could infect multiple different hosts with no or only a few additional mutations. Overall, these studies demonstrate that the evolutionary history of a virus, including how long it has been circulating and in which hosts, as well as its phylogenetic background, has a profound effect on determining viral host range.

  15. Back to basics: the untreated rabbit reticulocyte lysate as a competitive system to recapitulate cap/poly(A) synergy and the selective advantage of IRES-driven translation.

    Science.gov (United States)

    Soto Rifo, Ricardo; Ricci, Emiliano P; Décimo, Didier; Moncorgé, Olivier; Ohlmann, Théophile

    2007-01-01

    Translation of most eukaryotic mRNAs involves the synergistic action between the 5' cap structure and the 3' poly(A) tail at the initiation step. The poly(A) tail has also been shown to stimulate translation of picornavirus internal ribosome entry sites (IRES)-directed translation. These effects have been attributed principally to interactions between eIF4G and poly(A)-binding protein (PABP) but also to the participation of PABP in other steps during translation initiation. As the rabbit reticulocyte lysate (RRL) does not recapitulate this cap/poly(A) synergy, several systems based on cellular cell-free extracts have been developed to study the effects of poly(A) tail in vitro but they generally exhibit low translational efficiency. Here, we describe that the non-nuclease-treated RRL (untreated RRL) is able to recapitulate the effects of poly(A) tail on translation in vitro. In this system, translation of a capped/polyadenylated RNA was specifically inhibited by either Paip2 or poly(rA), whereas translation directed by HCV IRES remained unaffected. Moreover, cleavage of eIF4G by FMDV L protease strongly stimulated translation directed by the EMCV IRES, thus recapitulating the competitive advantage that the proteolytic processing of eIF4G confers to IRES-driven RNAs.

  16. Extensive Tonotopic Mapping across Auditory Cortex Is Recapitulated by Spectrally Directed Attention and Systematically Related to Cortical Myeloarchitecture.

    Science.gov (United States)

    Dick, Frederic K; Lehet, Matt I; Callaghan, Martina F; Keller, Tim A; Sereno, Martin I; Holt, Lori L

    2017-12-13

    diverse pathologies reduce quality of life by impacting such spectrally directed auditory attention, its neurobiological bases are unclear. We demonstrate that human primary and nonprimary auditory cortical activation is modulated by spectrally directed attention in a manner that recapitulates its tonotopic sensory organization. Further, the graded activation profiles evoked by single-frequency bands are correlated with attentionally driven activation when these bands are presented in complex soundscapes. Finally, we observe a strong concordance in the degree of cortical myelination and the strength of tonotopic activation across several auditory cortical regions. Copyright © 2017 Dick et al.

  17. EMT/MET at the Crossroad of Stemness, Regeneration and Oncogenesis: The Ying-Yang Equilibrium Recapitulated in Cell Spheroids

    Directory of Open Access Journals (Sweden)

    Elvira Forte

    2017-07-01

    Full Text Available The epithelial-to-mesenchymal transition (EMT is an essential trans-differentiation process, which plays a critical role in embryonic development, wound healing, tissue regeneration, organ fibrosis, and cancer progression. It is the fundamental mechanism by which epithelial cells lose many of their characteristics while acquiring features typical of mesenchymal cells, such as migratory capacity and invasiveness. Depending on the contest, EMT is complemented and balanced by the reverse process, the mesenchymal-to-epithelial transition (MET. In the saving economy of the living organisms, the same (Ying-Yang tool is integrated as a physiological strategy in embryonic development, as well as in the course of reparative or disease processes, prominently fibrosis, tumor invasion and metastasis. These mechanisms and their related signaling (e.g., TGF-β and BMPs have been effectively studied in vitro by tissue-derived cell spheroids models. These three-dimensional (3D cell culture systems, whose phenotype has been shown to be strongly dependent on TGF-β-regulated EMT/MET processes, present the advantage of recapitulating in vitro the hypoxic in vivo micro-environment of tissue stem cell niches and their formation. These spheroids, therefore, nicely reproduce the finely regulated Ying-Yang equilibrium, which, together with other mechanisms, can be determinant in cell fate decisions in many pathophysiological scenarios, such as differentiation, fibrosis, regeneration, and oncogenesis. In this review, current progress in the knowledge of signaling pathways affecting EMT/MET and stemness regulation will be outlined by comparing data obtained from cellular spheroids systems, as ex vivo niches of stem cells derived from normal and tumoral tissues. The mechanistic correspondence in vivo and the possible pharmacological perspective will be also explored, focusing especially on the TGF-β-related networks, as well as others, such as SNAI1, PTEN, and EGR1. This

  18. Recapitulative list of the C.E.A. reports published by the French Atomic Energy Commission (n.757-1062, december 1957-december 1958) supplement to C.E.A. reports n. 593 and 756

    International Nuclear Information System (INIS)

    Schmiterlow, C.G.; Cohen, Y.

    1958-01-01

    Recapitulative list of the C.E.A. reports published by the French Atomic Energy Commission. (number 757-1062, december 1957 - december 1958). Supplement to C.E.A. reports number 593 and 756. (author) [fr

  19. Recapitulative list of the C.E.A. reports published by the French Atomic Energy Commission (n.757-1062, december 1957-december 1958) supplement to C.E.A. reports n. 593 and 756; Liste recapitulative des rapports C.E.A. publies par le Commissariat a l'Energie Atomique (du n.757 a 1062, decembre 1957-decembre 1958) complement aux rapports C.E.A. n. 593 et 756

    Energy Technology Data Exchange (ETDEWEB)

    Schmiterlow, C G; Cohen, Y [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Recapitulative list of the C.E.A. reports published by the French Atomic Energy Commission. (number 757-1062, december 1957 - december 1958). Supplement to C.E.A. reports number 593 and 756. (author) [French] Liste recapitulative des rapports C.E.A. publies par le Commissariat a l'Energie Atomique (du numero 757 au numero 1062, decembre 1957 - decembre 1958). Complement aux rapports C.E.A. numero 593 et 756. (auteur)

  20. Recapitulation of tumor heterogeneity and molecular signatures in a 3D brain cancer model with decreased sensitivity to histone deacetylase inhibition.

    Directory of Open Access Journals (Sweden)

    Stuart J Smith

    Full Text Available INTRODUCTION: Physiologically relevant pre-clinical ex vivo models recapitulating CNS tumor micro-environmental complexity will aid development of biologically-targeted agents. We present comprehensive characterization of tumor aggregates generated using the 3D Rotary Cell Culture System (RCCS. METHODS: CNS cancer cell lines were grown in conventional 2D cultures and the RCCS and comparison with a cohort of 53 pediatric high grade gliomas conducted by genome wide gene expression and microRNA arrays, coupled with immunohistochemistry, ex vivo magnetic resonance spectroscopy and drug sensitivity evaluation using the histone deacetylase inhibitor, Vorinostat. RESULTS: Macroscopic RCCS aggregates recapitulated the heterogeneous morphology of brain tumors with a distinct proliferating rim, necrotic core and oxygen tension gradient. Gene expression and microRNA analyses revealed significant differences with 3D expression intermediate to 2D cultures and primary brain tumors. Metabolic profiling revealed differential profiles, with an increase in tumor specific metabolites in 3D. To evaluate the potential of the RCCS as a drug testing tool, we determined the efficacy of Vorinostat against aggregates of U87 and KNS42 glioblastoma cells. Both lines demonstrated markedly reduced sensitivity when assaying in 3D culture conditions compared to classical 2D drug screen approaches. CONCLUSIONS: Our comprehensive characterization demonstrates that 3D RCCS culture of high grade brain tumor cells has profound effects on the genetic, epigenetic and metabolic profiles of cultured cells, with these cells residing as an intermediate phenotype between that of 2D cultures and primary tumors. There is a discrepancy between 2D culture and tumor molecular profiles, and RCCS partially re-capitulates tissue specific features, allowing drug testing in a more relevant ex vivo system.

  1. Ablation of fast-spiking interneurons in the dorsal striatum, recapitulating abnormalities seen post-mortem in Tourette syndrome, produces anxiety and elevated grooming.

    Science.gov (United States)

    Xu, M; Li, L; Pittenger, C

    2016-06-02

    Tic disorders, including Tourette syndrome (TS), are thought to involve pathology of cortico-basal ganglia loops, but their pathology is not well understood. Post-mortem studies have shown a reduced number of several populations of striatal interneurons, including the parvalbumin-expressing fast-spiking interneurons (FSIs), in individuals with severe, refractory TS. We tested the causal role of this interneuronal deficit by recapitulating it in an otherwise normal adult mouse using a combination transgenic-viral cell ablation approach. FSIs were reduced bilaterally by ∼40%, paralleling the deficit found post-mortem. This did not produce spontaneous stereotypies or tic-like movements, but there was increased stereotypic grooming after acute stress in two validated paradigms. Stereotypy after amphetamine, in contrast, was not elevated. FSI ablation also led to increased anxiety-like behavior in the elevated plus maze, but not to alterations in motor learning on the rotorod or to alterations in prepulse inhibition, a measure of sensorimotor gating. These findings indicate that a striatal FSI deficit can produce stress-triggered repetitive movements and anxiety. These repetitive movements may recapitulate aspects of the pathophysiology of tic disorders. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  2. HSC extrinsic sex-related and intrinsic autoimmune disease-related human B-cell variation is recapitulated in humanized mice.

    Science.gov (United States)

    Borsotti, Chiara; Danzl, Nichole M; Nauman, Grace; Hölzl, Markus A; French, Clare; Chavez, Estefania; Khosravi-Maharlooei, Mohsen; Glauzy, Salome; Delmotte, Fabien R; Meffre, Eric; Savage, David G; Campbell, Sean R; Goland, Robin; Greenberg, Ellen; Bi, Jing; Satwani, Prakash; Yang, Suxiao; Bathon, Joan; Winchester, Robert; Sykes, Megan

    2017-10-24

    B cells play a major role in antigen presentation and antibody production in the development of autoimmune diseases, and some of these diseases disproportionally occur in females. Moreover, immune responses tend to be stronger in female vs male humans and mice. Because it is challenging to distinguish intrinsic from extrinsic influences on human immune responses, we used a personalized immune (PI) humanized mouse model, in which immune systems were generated de novo from adult human hematopoietic stem cells (HSCs) in immunodeficient mice. We assessed the effect of recipient sex and of donor autoimmune diseases (type 1 diabetes [T1D] and rheumatoid arthritis [RA]) on human B-cell development in PI mice. We observed that human B-cell levels were increased in female recipients regardless of the source of human HSCs or the strain of immunodeficient recipient mice. Moreover, mice injected with T1D- or RA-derived HSCs displayed B-cell abnormalities compared with healthy control HSC-derived mice, including altered B-cell levels, increased proportions of mature B cells and reduced CD19 expression. Our study revealed an HSC-extrinsic effect of recipient sex on human B-cell reconstitution. Moreover, the PI humanized mouse model revealed HSC-intrinsic defects in central B-cell tolerance that recapitulated those in patients with autoimmune diseases. These results demonstrate the utility of humanized mouse models as a tool to better understand human immune cell development and regulation.

  3. The Aorta-Gonad-Mesonephros Organ Culture Recapitulates 5hmC Reorganization and Replication-Dependent and Independent Loss of DNA Methylation in the Germline.

    Science.gov (United States)

    Calvopina, Joseph Hargan; Cook, Helene; Vincent, John J; Nee, Kevin; Clark, Amander T

    2015-07-01

    Removal of cytosine methylation from the genome is critical for reprogramming and transdifferentiation and plays a central role in our understanding of the fundamental principles of embryo lineage development. One of the major models for studying cytosine demethylation is the mammalian germ line during the primordial germ cell (PGC) stage of embryo development. It is now understood that oxidation of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) is required to remove cytosine methylation in a locus-specific manner in PGCs; however, the mechanisms downstream of 5hmC are controversial and hypothesized to involve either active demethylation or replication-coupled loss. In the current study, we used the aorta-gonad-mesonephros (AGM) organ culture model to show that this model recapitulates germ line reprogramming, including 5hmC reorganization and loss of cytosine methylation from Snrpn and H19 imprinting control centers (ICCs). To directly address the hypothesis that cell proliferation is required for cytosine demethylation, we blocked PI3-kinase-dependent PGC proliferation and show that this leads to a G1 and G2/M cell cycle arrest in PGCs, together with retained levels of cytosine methylation at the Snrpn ICC, but not at the H19 ICC. Taken together, the AGM organ culture model is an important tool to evaluate mechanisms of locus-specific demethylation and the role of PI3-kinase-dependent PGC proliferation in the locus-specific removal of cytosine methylation from the genome.

  4. Ultrastructural investigation and in vitro recapitulation of spermatid differentiation in a potential bio-indicator species - The marine invertebrate Galeolaria gemineoa (Polychaeta: Serpulidae.

    Directory of Open Access Journals (Sweden)

    Yonggang Lu

    Full Text Available Galeolaria gemineoa is a sessile broadcast-spawning marine invertebrate, whose spermatozoa have been regarded as a sensitive indicator for water quality monitoring. In this study, 10 steps of spermiogenesis have been identified at the ultrastructural level and this differentiation process has been recapitulated in vitro up to the point of spermiogenesis (step 7-9 spermatids. On completion of the second meiosis, newly formed spermatids were detached from the seminiferous epithelium and released to the lumen of each germinal chamber. These spermatids were present in pairs and interconnected by a cytoplasmic bridge throughout the entire spermiogenic process. On the basis of morphological events such as formation of the acrosome, elongation of the flagellum, and condensation of the nucleus, spermiogenesis has been temporally divided into Golgi phase, acrosomal phase and maturation phase. During the Golgi phase, proacrosomal vesicles appeared at the posterior pole of the spermatids and gradually fused into a proacrosomal vacuole. Simultaneously, the distal centriole docked onto the plasma membrane and gave rise to a formative flagellum. The acrosomal phase was characterised by differentiation of the acrosome, condensation of the chromatin and formation of a mitochondrial sheath surrounding the initial portion of the flagellum. During the maturation phase, the fully differentiated acrosome migrated to the anterior pole and excess cytoplasm was extruded from the spermatids in the form of residual bodies. In addition, we successfully induced step 1-3 spermatids to differentiate into the step 7-9 spermatids in both male germinal fluid and 10% foetal bovine serum in RPMI 1640 medium, but failed to replicate this process in female or boiled male germinal fluids. This finding supports our concept that spermatid differentiation in this species is dependent on intrinsic developmental programming and does not require input from accompanying nurse cells.

  5. Mice long-term high-fat diet feeding recapitulates human cardiovascular alterations: an animal model to study the early phases of diabetic cardiomyopathy.

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    Sebastián D Calligaris

    Full Text Available BACKGROUND/AIM: Hypercaloric diet ingestion and sedentary lifestyle result in obesity. Metabolic syndrome is a cluster of clinical features secondary to obesity, considered as a pre-diabetic condition and recognized as an independent risk factor for cardiovascular diseases. To better understand the relationship between obesity, metabolic syndrome and cardiovascular disease as well as for the development of novel therapeutic strategies, animal models that reproduce the etiology, course and outcomes of these pathologies are required. The aim of this work was to characterize the long-term effects of high-fat diet-induced obesity on the mice cardiovascular system, in order to make available a new animal model for diabetic cardiomyopathy. METHODS/RESULTS: Male C57BL/6 mice were fed with a standardized high-fat diet (obese or regular diet (normal for 16 months. Metabolic syndrome was evaluated testing plasma glucose, triglycerides, cholesterol, insulin, and glucose tolerance. Arterial pressure was measured using a sphygmomanometer (non invasive method and by hemodynamic parameters (invasive method. Cardiac anatomy was described based on echocardiography and histological studies. Cardiac function was assessed by cardiac catheterization under a stress test. Cardiac remodelling and metabolic biomarkers were assessed by RT-qPCR and immunoblotting. As of month eight, the obese mice were overweight, hyperglycaemic, insulin resistant, hyperinsulinemic and hypercholesterolemic. At month 16, they also presented normal arterial pressure but altered vascular reactivity (vasoconstriction, and cardiac contractility reserve reduction, heart mass increase, cardiomyocyte hypertrophy, cardiac fibrosis, and heart metabolic compensations. By contrast, the normal mice remained healthy throughout the study. CONCLUSIONS: Mice fed with a high-fat diet for prolonged time recapitulates the etiology, course and outcomes of the early phases of human diabetic cardiomyopathy.

  6. A mammalian conserved element derived from SINE displays enhancer properties recapitulating Satb2 expression in early-born callosal projection neurons.

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    Kensuke Tashiro

    Full Text Available Short interspersed repetitive elements (SINEs are highly repeated sequences that account for a significant proportion of many eukaryotic genomes and are usually considered "junk DNA". However, we previously discovered that many AmnSINE1 loci are evolutionarily conserved across mammalian genomes, suggesting that they may have acquired significant functions involved in controlling mammalian-specific traits. Notably, we identified the AS021 SINE locus, located 390 kbp upstream of Satb2. Using transgenic mice, we showed that this SINE displays specific enhancer activity in the developing cerebral cortex. The transcription factor Satb2 is expressed by cortical neurons extending axons through the corpus callosum and is a determinant of callosal versus subcortical projection. Mouse mutants reveal a crucial function for Sabt2 in corpus callosum formation. In this study, we compared the enhancer activity of the AS021 locus with Satb2 expression during telencephalic development in the mouse. First, we showed that the AS021 enhancer is specifically activated in early-born Satb2(+ neurons. Second, we demonstrated that the activity of the AS021 enhancer recapitulates the expression of Satb2 at later embryonic and postnatal stages in deep-layer but not superficial-layer neurons, suggesting the possibility that the expression of Satb2 in these two subpopulations of cortical neurons is under genetically distinct transcriptional control. Third, we showed that the AS021 enhancer is activated in neurons projecting through the corpus callosum, as described for Satb2(+ neurons. Notably, AS021 drives specific expression in axons crossing through the ventral (TAG1(-/NPY(+ portion of the corpus callosum, confirming that it is active in a subpopulation of callosal neurons. These data suggest that exaptation of the AS021 SINE locus might be involved in enhancement of Satb2 expression, leading to the establishment of interhemispheric communication via the corpus callosum

  7. Toward Personalized Medicine: Using Cardiomyocytes Differentiated From Urine-Derived Pluripotent Stem Cells to Recapitulate Electrophysiological Characteristics of Type 2 Long QT Syndrome.

    Science.gov (United States)

    Jouni, Mariam; Si-Tayeb, Karim; Es-Salah-Lamoureux, Zeineb; Latypova, Xenia; Champon, Benoite; Caillaud, Amandine; Rungoat, Anais; Charpentier, Flavien; Loussouarn, Gildas; Baró, Isabelle; Zibara, Kazem; Lemarchand, Patricia; Gaborit, Nathalie

    2015-09-01

    Human genetically inherited cardiac diseases have been studied mainly in heterologous systems or animal models, independent of patients' genetic backgrounds. Because sources of human cardiomyocytes (CMs) are extremely limited, the use of urine samples to generate induced pluripotent stem cell-derived CMs would be a noninvasive method to identify cardiac dysfunctions that lead to pathologies within patients' specific genetic backgrounds. The objective was to validate the use of CMs differentiated from urine-derived human induced pluripotent stem (UhiPS) cells as a new cellular model for studying patients' specific arrhythmia mechanisms. Cells obtained from urine samples of a patient with long QT syndrome who harbored the HERG A561P gene mutation and his asymptomatic noncarrier mother were reprogrammed using the episomal-based method. UhiPS cells were then differentiated into CMs using the matrix sandwich method.UhiPS-CMs showed proper expression of atrial and ventricular myofilament proteins and ion channels. They were electrically functional, with nodal-, atrial- and ventricular-like action potentials recorded using high-throughput optical and patch-clamp techniques. Comparison of HERG expression from the patient's UhiPS-CMs to the mother's UhiPS-CMs showed that the mutation led to a trafficking defect that resulted in reduced delayed rectifier K(+) current (IKr). This phenotype gave rise to action potential prolongation and arrhythmias. UhiPS cells from patients carrying ion channel mutations can be used as novel tools to differentiate functional CMs that recapitulate cardiac arrhythmia phenotypes. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  8. Computational cell model based on autonomous cell movement regulated by cell-cell signalling successfully recapitulates the "inside and outside" pattern of cell sorting

    Directory of Open Access Journals (Sweden)

    Ajioka Itsuki

    2007-09-01

    Full Text Available Abstract Background Development of multicellular organisms proceeds from a single fertilized egg as the combined effect of countless numbers of cellular interactions among highly dynamic cells. Since at least a reminiscent pattern of morphogenesis can be recapitulated in a reproducible manner in reaggregation cultures of dissociated embryonic cells, which is known as cell sorting, the cells themselves must possess some autonomous cell behaviors that assure specific and reproducible self-organization. Understanding of this self-organized dynamics of heterogeneous cell population seems to require some novel approaches so that the approaches bridge a gap between molecular events and morphogenesis in developmental and cell biology. A conceptual cell model in a computer may answer that purpose. We constructed a dynamical cell model based on autonomous cell behaviors, including cell shape, growth, division, adhesion, transformation, and motility as well as cell-cell signaling. The model gives some insights about what cellular behaviors make an appropriate global pattern of the cell population. Results We applied the model to "inside and outside" pattern of cell-sorting, in which two different embryonic cell types within a randomly mixed aggregate are sorted so that one cell type tends to gather in the central region of the aggregate and the other cell type surrounds the first cell type. Our model can modify the above cell behaviors by varying parameters related to them. We explored various parameter sets with which the "inside and outside" pattern could be achieved. The simulation results suggested that direction of cell movement responding to its neighborhood and the cell's mobility are important for this specific rearrangement. Conclusion We constructed an in silico cell model that mimics autonomous cell behaviors and applied it to cell sorting, which is a simple and appropriate phenomenon exhibiting self-organization of cell population. The model

  9. Subthreshold Desensitization of Human Basophils Re-capitulates the Loss of syk and FcεRI expression Characterized by Other Methods of Desensitization

    Science.gov (United States)

    MacGlashan, Donald

    2012-01-01

    Background Clinical desensitization of patients to drugs involves progressive exposure to escalating doses of drug over a period of 24 hours. In prior studies, this method was recapitulated in vitro to also demonstrate loss of mast cell or basophil responsiveness. However, most signaling studies of human basophils have identified changes in signaling by using other methods of inducing cellular desensitization. Objective This study examined two well-described endpoints of basophil desensitization, loss of syk or FcεRI expression, under conditions of subthreshold desensitization. Methods The loss of FceRI and syk was examined in human basophils. Results It was shown that both loss of syk and FcεRI/IgE occurred during an escalating series of stimulation (anti-IgE Ab) and that expression loss occurred despite the presence of little histamine release. If basophils were first cultured for 3 days in 10 ng/ml IL-3, the concentration-dependence of histamine release shifted to 100 fold lower concentrations of stimulus. However, loss of syk did not show any change in its EC50 while loss of FcεRI also shifted 100 fold. From the perspective of early signal element activation, the marked shift in the EC50 for histamine release was not accompanied by similar shifts in the EC50s for several signaling elements. The EC50s for phospho-Src, phospho-SHIP1, phospho-Syk, or phospho-Cbl did not change while the EC50s for phospho-Erk and the cytosolic calcium response did shift 100 fold. Conclusions These studies show that under normal conditions, subthreshold desensitization leads to loss of two critical signaling molecules (FcεRI and syk) but under at least one condition, treatment with IL-3, it is possible to markedly blunt the loss of syk, but not FcεRI, while executing a proper subthreshold titration. These data also suggest that IL-3 modifies only the sensitivity of signaling elements that are downstream of syk activation. PMID:22702505

  10. Aims and methods of education: A recapitulation

    Directory of Open Access Journals (Sweden)

    Pantić Nataša

    2007-01-01

    Full Text Available This paper gives an overview of principal distinction between the aims of the so-called "traditional" and "progressive" education and respective pedagogies associated with each. The term "traditional" education is used to denote the kind of education that prepares people for their role in society as it is, while the term "progressive" is used for education that aspires to equip mankind with capacity to shape the change of society. The paper raises some critical questions about the role of pedagogy in achieving the aims of the progressive model, arguing that the employment of "progressive" methods does not necessarily guarantee the achievement of the commonly professed purposes of progressive education. This is illustrated in the paper by the results of a study in English schools showing how despite the claim of progressive methods, teachers tend to retain traditional attitudes and on the other hand, how even traditional teaching methods can serve the progressive purpose. This is not to advocate for the traditional pedagogy, but to suggest that it might be something other than pedagogy that makes a critical difference in educating liberal-minded citizens of the future. In this sense the paper explores the role of other factors that make a difference towards progressive education, such as democratization of human relations in school ethos and respect for children's freedom.

  11. Extracellular matrix components expression in human pluripotent stem cell-derived retinal organoids recapitulates retinogenesis in vivo and reveals an important role for IMPG1 and CD44 in the development of photoreceptors and interphotoreceptor matrix.

    Science.gov (United States)

    Felemban, Majed; Dorgau, Birthe; Hunt, Nicola Claire; Hallam, Dean; Zerti, Darin; Bauer, Roman; Ding, Yuchun; Collin, Joseph; Steel, David; Krasnogor, Natalio; Al-Aama, Jumana; Lindsay, Susan; Mellough, Carla; Lako, Majlinda

    2018-05-17

    , IMPG1 & IMPG2 in the developing interphotoreceptor matrix (IPM). Retinal organoids were successfully generated from pluripotent stem cells. The expression of ECM components was examined in the retinal organoids and found to recapitulate human retinal development in vivo. Using functional blocking experiments, we were able to highlight an important role for IMPG1 and CD44 in the development of photoreceptors and IPM formation. Copyright © 2018 Acta Materialia Inc. All rights reserved.

  12. Can injured adult CNS axons regenerate by recapitulating development?

    Science.gov (United States)

    Hilton, Brett J; Bradke, Frank

    2017-10-01

    In the adult mammalian central nervous system (CNS), neurons typically fail to regenerate their axons after injury. During development, by contrast, neurons extend axons effectively. A variety of intracellular mechanisms mediate this difference, including changes in gene expression, the ability to form a growth cone, differences in mitochondrial function/axonal transport and the efficacy of synaptic transmission. In turn, these intracellular processes are linked to extracellular differences between the developing and adult CNS. During development, the extracellular environment directs axon growth and circuit formation. In adulthood, by contrast, extracellular factors, such as myelin and the extracellular matrix, restrict axon growth. Here, we discuss whether the reactivation of developmental processes can elicit axon regeneration in the injured CNS. © 2017. Published by The Company of Biologists Ltd.

  13. Mouse Models Recapitulating Human Adrenocortical Tumors: What is lacking?

    Directory of Open Access Journals (Sweden)

    Felicia Leccia

    2016-07-01

    Full Text Available Adrenal cortex tumors are divided into benign forms such as primary hyperplasias and adrenocortical adenomas (ACAs, and malignant forms or adrenocortical carcinomas (ACCs. Primary hyperplasias are rare causes of ACTH-independent hypercortisolism. ACAs are the most common type of adrenal gland tumors and they are rarely functional, i.e producing steroids. When functional, adenomas result in endocrine disorders such as Cushing’s syndrome (hypercortisolism or Conn’s syndrome (hyperaldosteronism. In contrast, ACCs are extremely rare but highly aggressive tumors that may also lead to hypersecreting syndromes. Genetic analyses of patients with sporadic or familial forms of adrenocortical tumors led to the identification of potentially causative genes, most of them being involved in PKA, Wnt/β-catenin and P53 signaling pathways. Development of mouse models is a crucial step to firmly establish the functional significance of candidate genes, to dissect mechanisms leading to tumors and endocrine disorders and in fine to provide in vivo tools for therapeutic screens. In this article we will provide an overview on the existing mouse models (xenografted and genetically engineered of adrenocortical tumors by focusing on the role of PKA and Wnt/β-catenin pathways in this context. We will discuss the advantages and limitations of models that have been developed heretofore and we will point out necessary improvements in the development of next generation mouse models of adrenal diseases.

  14. Human pancreatic cancer xenografts recapitulate key aspects of cancer cachexia.

    Science.gov (United States)

    Delitto, Daniel; Judge, Sarah M; Delitto, Andrea E; Nosacka, Rachel L; Rocha, Fernanda G; DiVita, Bayli B; Gerber, Michael H; George, Thomas J; Behrns, Kevin E; Hughes, Steven J; Wallet, Shannon M; Judge, Andrew R; Trevino, Jose G

    2017-01-03

    Cancer cachexia represents a debilitating syndrome that diminishes quality of life and augments the toxicities of conventional treatments. Cancer cachexia is particularly debilitating in patients with pancreatic cancer (PC). Mechanisms responsible for cancer cachexia are under investigation and are largely derived from observations in syngeneic murine models of cancer which are limited in PC. We evaluate the effect of human PC cells on both muscle wasting and the systemic inflammatory milieu potentially contributing to PC-associated cachexia. Specifically, human PC xenografts were generated by implantation of pancreatic cancer cells, L3.6pl and PANC-1, either in the flank or orthotopically within the pancreas. Mice bearing orthotopic xenografts demonstrated significant muscle wasting and atrophy-associated gene expression changes compared to controls. Further, despite the absence of adaptive immunity, splenic tissue from orthotopically engrafted mice demonstrated elevations in several pro-inflammatory cytokines associated with cancer cachexia, including TNFα, IL1β, IL6 and KC (murine IL8 homologue), when compared to controls. Therefore, data presented here support further investigation into the complexity of cancer cachexia in PC to identify potential targets for this debilitating syndrome.

  15. America, guns, and freedom. Part I: A recapitulation of liberty.

    Science.gov (United States)

    Faria, Miguel A

    2012-01-01

    The role of gun violence and street crime in the United States and the world is currently a subject of great debate among national and international organizations, including the United Nations. Because the Second Amendment to the U.S. Constitution protects the individual right of American citizens to own private firearms, availability of firearms is greater in the U.S. than the rest of the world, except perhaps in Israel and Switzerland. Indeed, although the American people continue to purchase and possess more firearms, homicides and violent crimes have continued to diminish for several decades because guns in the hands of the law-abiding citizens does not translate into more crime. As neurosurgeons, we can be compassionate and still be honest and have the moral courage to pursue the truth and find viable solutions through the use of sound, scholarly research in the area of guns and violence. We have an obligation to reach our conclusions based on objective data and scientific information rather than on ideology, emotionalism or partisan politics.

  16. Engineering Hydrogel Microenvironments to Recapitulate the Stem Cell Niche.

    Science.gov (United States)

    Madl, Christopher M; Heilshorn, Sarah C

    2018-06-04

    Stem cells are a powerful resource for many applications including regenerative medicine, patient-specific disease modeling, and toxicology screening. However, eliciting the desired behavior from stem cells, such as expansion in a naïve state or differentiation into a particular mature lineage, remains challenging. Drawing inspiration from the native stem cell niche, hydrogel platforms have been developed to regulate stem cell fate by controlling microenvironmental parameters including matrix mechanics, degradability, cell-adhesive ligand presentation, local microstructure, and cell-cell interactions. We survey techniques for modulating hydrogel properties and review the effects of microenvironmental parameters on maintaining stemness and controlling differentiation for a variety of stem cell types. Looking forward, we envision future hydrogel designs spanning a spectrum of complexity, ranging from simple, fully defined materials for industrial expansion of stem cells to complex, biomimetic systems for organotypic cell culture models.

  17. A Syrian golden hamster model recapitulating ebola hemorrhagic fever.

    Science.gov (United States)

    Ebihara, Hideki; Zivcec, Marko; Gardner, Donald; Falzarano, Darryl; LaCasse, Rachel; Rosenke, Rebecca; Long, Dan; Haddock, Elaine; Fischer, Elizabeth; Kawaoka, Yoshihiro; Feldmann, Heinz

    2013-01-15

    Ebola hemorrhagic fever (EHF) is a severe viral infection for which no effective treatment or vaccine is currently available. While the nonhuman primate (NHP) model is used for final evaluation of experimental vaccines and therapeutic efficacy, rodent models have been widely used in ebolavirus research because of their convenience. However, the validity of rodent models has been questioned given their low predictive value for efficacy testing of vaccines and therapeutics, a result of the inconsistent manifestation of coagulopathy seen in EHF. Here, we describe a lethal Syrian hamster model of EHF using mouse-adapted Ebola virus. Infected hamsters displayed most clinical hallmarks of EHF, including severe coagulopathy and uncontrolled host immune responses. Thus, the hamster seems to be superior to the existing rodent models, offering a better tool for understanding the critical processes in pathogenesis and providing a new model for evaluating prophylactic and postexposure interventions prior to testing in NHPs.

  18. Integrating light-sheet imaging with virtual reality to recapitulate developmental cardiac mechanics.

    Science.gov (United States)

    Ding, Yichen; Abiri, Arash; Abiri, Parinaz; Li, Shuoran; Chang, Chih-Chiang; Baek, Kyung In; Hsu, Jeffrey J; Sideris, Elias; Li, Yilei; Lee, Juhyun; Segura, Tatiana; Nguyen, Thao P; Bui, Alexander; Sevag Packard, René R; Fei, Peng; Hsiai, Tzung K

    2017-11-16

    Currently, there is a limited ability to interactively study developmental cardiac mechanics and physiology. We therefore combined light-sheet fluorescence microscopy (LSFM) with virtual reality (VR) to provide a hybrid platform for 3D architecture and time-dependent cardiac contractile function characterization. By taking advantage of the rapid acquisition, high axial resolution, low phototoxicity, and high fidelity in 3D and 4D (3D spatial + 1D time or spectra), this VR-LSFM hybrid methodology enables interactive visualization and quantification otherwise not available by conventional methods, such as routine optical microscopes. We hereby demonstrate multiscale applicability of VR-LSFM to (a) interrogate skin fibroblasts interacting with a hyaluronic acid-based hydrogel, (b) navigate through the endocardial trabecular network during zebrafish development, and (c) localize gene therapy-mediated potassium channel expression in adult murine hearts. We further combined our batch intensity normalized segmentation algorithm with deformable image registration to interface a VR environment with imaging computation for the analysis of cardiac contraction. Thus, the VR-LSFM hybrid platform demonstrates an efficient and robust framework for creating a user-directed microenvironment in which we uncovered developmental cardiac mechanics and physiology with high spatiotemporal resolution.

  19. K-RasV14I recapitulates Noonan syndrome in mice

    Science.gov (United States)

    Hernández-Porras, Isabel; Fabbiano, Salvatore; Schuhmacher, Alberto J.; Aicher, Alexandra; Cañamero, Marta; Cámara, Juan Antonio; Cussó, Lorena; Desco, Manuel; Heeschen, Christopher; Mulero, Francisca; Bustelo, Xosé R.; Guerra, Carmen; Barbacid, Mariano

    2014-01-01

    Noonan syndrome (NS) is an autosomal dominant genetic disorder characterized by short stature, craniofacial dysmorphism, and congenital heart defects. NS also is associated with a risk for developing myeloproliferative disorders (MPD), including juvenile myelomonocytic leukemia (JMML). Mutations responsible for NS occur in at least 11 different loci including KRAS. Here we describe a mouse model for NS induced by K-RasV14I, a recurrent KRAS mutation in NS patients. K-RasV14I–mutant mice displayed multiple NS-associated developmental defects such as growth delay, craniofacial dysmorphia, cardiac defects, and hematologic abnormalities including a severe form of MPD that resembles human JMML. Homozygous animals had perinatal lethality whose penetrance varied with genetic background. Exposure of pregnant mothers to a MEK inhibitor rescued perinatal lethality and prevented craniofacial dysmorphia and cardiac defects. However, Mek inhibition was not sufficient to correct these defects when mice were treated after weaning. Interestingly, Mek inhibition did not correct the neoplastic MPD characteristic of these mutant mice, regardless of the timing at which the mice were treated, thus suggesting that MPD is driven by additional signaling pathways. These genetically engineered K-RasV14I–mutant mice offer an experimental tool for studying the molecular mechanisms underlying the clinical manifestations of NS. Perhaps more importantly, they should be useful as a preclinical model to test new therapies aimed at preventing or ameliorating those deficits associated with this syndrome. PMID:25359213

  20. A Novel Mouse Model of a Patient Mucolipidosis II Mutation Recapitulates Disease Pathology*

    OpenAIRE

    Paton, Leigh; Bitoun, Emmanuelle; Kenyon, Janet; Priestman, David A.; Oliver, Peter L.; Edwards, Benjamin; Platt, Frances M.; Davies, Kay E.

    2014-01-01

    Mucolipidosis II (MLII) is a lysosomal storage disorder caused by loss of N-acetylglucosamine-1-phosphotransferase, which tags lysosomal enzymes with a mannose 6-phosphate marker for transport to the lysosome. In MLII, the loss of this marker leads to deficiency of multiple enzymes and non-enzymatic proteins in the lysosome, leading to the storage of multiple substrates. Here we present a novel mouse model of MLII homozygous for a patient mutation in the GNPTAB gene. Whereas the current gene ...

  1. Fenton reaction induced cancer in wild type rats recapitulates genomic alterations observed in human cancer.

    Directory of Open Access Journals (Sweden)

    Shinya Akatsuka

    Full Text Available Iron overload has been associated with carcinogenesis in humans. Intraperitoneal administration of ferric nitrilotriacetate initiates a Fenton reaction in renal proximal tubules of rodents that ultimately leads to a high incidence of renal cell carcinoma (RCC after repeated treatments. We performed high-resolution microarray comparative genomic hybridization to identify characteristics in the genomic profiles of this oxidative stress-induced rat RCCs. The results revealed extensive large-scale genomic alterations with a preference for deletions. Deletions and amplifications were numerous and sometimes fragmented, demonstrating that a Fenton reaction is a cause of such genomic alterations in vivo. Frequency plotting indicated that two of the most commonly altered loci corresponded to a Cdkn2a/2b deletion and a Met amplification. Tumor sizes were proportionally associated with Met expression and/or amplification, and clustering analysis confirmed our results. Furthermore, we developed a procedure to compare whole genomic patterns of the copy number alterations among different species based on chromosomal syntenic relationship. Patterns of the rat RCCs showed the strongest similarity to the human RCCs among five types of human cancers, followed by human malignant mesothelioma, an iron overload-associated cancer. Therefore, an iron-dependent Fenton chemical reaction causes large-scale genomic alterations during carcinogenesis, which may result in distinct genomic profiles. Based on the characteristics of extensive genome alterations in human cancer, our results suggest that this chemical reaction may play a major role during human carcinogenesis.

  2. Recapitulation of premature ageing with iPSCs from Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Liu, Guang-Hui; Barkho, Basam Z; Ruiz, Sergio; Diep, Dinh; Qu, Jing; Yang, Sheng-Lian; Panopoulos, Athanasia D; Suzuki, Keiichiro; Kurian, Leo; Walsh, Christopher; Thompson, James; Boue, Stephanie; Fung, Ho Lim; Sancho-Martinez, Ignacio; Zhang, Kun; Yates, John; Izpisua Belmonte, Juan Carlos

    2011-04-14

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare and fatal human premature ageing disease, characterized by premature arteriosclerosis and degeneration of vascular smooth muscle cells (SMCs). HGPS is caused by a single point mutation in the lamin A (LMNA) gene, resulting in the generation of progerin, a truncated splicing mutant of lamin A. Accumulation of progerin leads to various ageing-associated nuclear defects including disorganization of nuclear lamina and loss of heterochromatin. Here we report the generation of induced pluripotent stem cells (iPSCs) from fibroblasts obtained from patients with HGPS. HGPS-iPSCs show absence of progerin, and more importantly, lack the nuclear envelope and epigenetic alterations normally associated with premature ageing. Upon differentiation of HGPS-iPSCs, progerin and its ageing-associated phenotypic consequences are restored. Specifically, directed differentiation of HGPS-iPSCs to SMCs leads to the appearance of premature senescence phenotypes associated with vascular ageing. Additionally, our studies identify DNA-dependent protein kinase catalytic subunit (DNAPKcs, also known as PRKDC) as a downstream target of progerin. The absence of nuclear DNAPK holoenzyme correlates with premature as well as physiological ageing. Because progerin also accumulates during physiological ageing, our results provide an in vitro iPSC-based model to study the pathogenesis of human premature and physiological vascular ageing.

  3. klf2ash317 Mutant Zebrafish Do Not Recapitulate Morpholino-Induced Vascular and Haematopoietic Phenotypes.

    Directory of Open Access Journals (Sweden)

    Peter Novodvorsky

    Full Text Available The zinc-finger transcription factor Krϋppel-like factor 2 (KLF2 transduces blood flow into molecular signals responsible for a wide range of responses within the vasculature. KLF2 maintains a healthy, quiescent endothelial phenotype. Previous studies report a range of phenotypes following morpholino antisense oligonucleotide-induced klf2a knockdown in zebrafish. Targeted genome editing is an increasingly applied method for functional assessment of candidate genes. We therefore generated a stable klf2a mutant zebrafish and characterised its cardiovascular and haematopoietic development.Using Transcription Activator-Like Effector Nucleases (TALEN we generated a klf2a mutant (klf2ash317 with a 14bp deletion leading to a premature stop codon in exon 2. Western blotting confirmed loss of wild type Klf2a protein and the presence of a truncated protein in klf2ash317 mutants. Homozygous klf2ash317 mutants exhibit no defects in vascular patterning, survive to adulthood and are fertile, without displaying previously described morphant phenotypes such as high-output cardiac failure, reduced haematopoetic stem cell (HSC development or impaired formation of the 5th accessory aortic arch. Homozygous klf2ash317 mutation did not reduce angiogenesis in zebrafish with homozygous mutations in von Hippel Lindau (vhl, a form of angiogenesis that is dependent on blood flow. We examined expression of three klf family members in wildtype and klf2ash317 zebrafish. We detected vascular expression of klf2b (but not klf4a or biklf/klf4b/klf17 in wildtypes but found no differences in expression that might account for the lack of phenotype in klf2ash317 mutants. klf2b morpholino knockdown did not affect heart rate or impair formation of the 5th accessory aortic arch in either wildtypes or klf2ash317 mutants.The klf2ash317 mutation produces a truncated Klf2a protein but, unlike morpholino induced klf2a knockdown, does not affect cardiovascular development.

  4. L1-mediated retrotransposition of murine B1 and B2 SINEs recapitulated in cultured cells.

    Science.gov (United States)

    Dewannieux, Marie; Heidmann, Thierry

    2005-06-03

    SINEs are short interspersed nucleotide elements with transpositional activity, present at a high copy number (up to a million) in mammalian genomes. They are 80-400 bp long, non-coding sequences which derive either from the 7SL RNA (e.g. human Alus, murine B1s) or tRNA (e.g. murine B2s) polymerase III-driven genes. We have previously demonstrated that Alus very efficiently divert the enzymatic machinery of the autonomous L1 LINE (long interspersed nucleotide element) retrotransposons to transpose at a high rate. Here we show, using an ex vivo assay for transposition, that both B1 and B2 SINEs can be mobilized by murine LINEs, with the hallmarks of a bona fide retrotransposition process, including target site duplications of varying lengths and integrations into A-rich sequences. Despite different phylogenetic origins, transposition of the tRNA-derived B2 sequences is as efficient as that of the human Alus, whereas that of B1s is 20-100-fold lower despite a similar high copy number of these elements in the mouse genome. We provide evidence, via an appropriate nucleotide substitution within the B1 sequence in a domain essential for its intracellular targeting, that the current B1 SINEs are not optimal for transposition, a feature most probably selected for the host sake in the course of evolution.

  5. Epithelial self-healing is recapitulated by a 3D biomimetic E-cadherin junction

    NARCIS (Netherlands)

    Cohen, Daniel J.; Gloerich, Martijn; Nelson, W. James

    2016-01-01

    Epithelial monolayers undergo self-healing when wounded. During healing, cells collectively migrate into the wound site, and the converging tissue fronts collide and form a stable interface. To heal, migrating tissues must form cell-cell adhesions and reorganize from the front-rear polarity

  6. The late negative episodic memory effect: the effect of recapitulating study details at test.

    Science.gov (United States)

    Friedman, David; Cycowicz, Yael M; Bersick, Michael

    2005-05-01

    An hypothesis concerning mnemonic function suggests that perceptual details of previously experienced episodes are retrieved from the cortices that initially processed that information during the encoding phase. Cycowicz et al. [Cycowicz, Y.M., Friedman, D. and Snodgrass, J.G., Remembering the color of objects: an ERP investigation of source memory, Cereb Cortex, 11 (2001) 322-334.] have interpreted the presence of a late negative episodic memory (EM) effect, maximal over parieto-occipital scalp, as a brain signature of the search for and/or retrieval/evaluation of the specific perceptual source-specifying attributes (i.e., color) of pictures in the visual cortical regions that were recruited during the encoding of that information. The present study assessed the validity of this hypothesis. Twelve participants studied pictures outlined in red or green and were subsequently tested with inclusion (i.e., item; old or new regardless of color) and exclusion (i.e., source; same color, different color/new judgments) tasks. In both, old pictures were presented either in the same color as at study or in the alternate color. A late negative, parieto-occipital EM effect was of much larger amplitude in the source compared to the item task. It was of similar magnitude to correctly recognized pictures whose colors were identical at study and test relative to those whose colors changed, and was not modulated by the success or failure of the source retrieval. These data run counter to the initial hypothesis that the late negative EM effect reflects the search for and/or retrieval of specific perceptual attributes such as color. Rather, the late negative EM effect may reflect the search for and/or retrieval/evaluation of more general source-specifying information in the cortical regions that initially processed the stimuli.

  7. Neo-sex chromosomes in the black muntjac recapitulate incipient evolution of mammalian sex chromosomes

    DEFF Research Database (Denmark)

    Zhou, Qi; Wang, Jun; Huang, Ling

    2008-01-01

    in coding regions of eight investigated genes as well as cis-regulatory regions of two housekeeping genes. In vivo assays characterized a neo-Y insertion in the promoter of the CLTC gene that causes a significant reduction in allelic expression. A neo-Y-linked deletion in the 3'-untranslated region of gene...

  8. Spontaneous 8bp Deletion in Nbeal2 Recapitulates the Gray Platelet Syndrome in Mice

    Science.gov (United States)

    Tomberg, Kärt; Khoriaty, Rami; Westrick, Randal J.; Fairfield, Heather E.; Reinholdt, Laura G.; Brodsky, Gary L.; Davizon-Castillo, Pavel; Ginsburg, David; Di Paola, Jorge

    2016-01-01

    During the analysis of a whole genome ENU mutagenesis screen for thrombosis modifiers, a spontaneous 8 base pair (bp) deletion causing a frameshift in exon 27 of the Nbeal2 gene was identified. Though initially considered as a plausible thrombosis modifier, this Nbeal2 mutation failed to suppress the synthetic lethal thrombosis on which the original ENU screen was based. Mutations in NBEAL2 cause Gray Platelet Syndrome (GPS), an autosomal recessive bleeding disorder characterized by macrothrombocytopenia and gray-appearing platelets due to lack of platelet alpha granules. Mice homozygous for the Nbeal2 8 bp deletion (Nbeal2gps/gps) exhibit a phenotype similar to human GPS, with significantly reduced platelet counts compared to littermate controls (p = 1.63 x 10−7). Nbeal2gps/gps mice also have markedly reduced numbers of platelet alpha granules and an increased level of emperipolesis, consistent with previously characterized mice carrying targeted Nbeal2 null alleles. These findings confirm previous reports, provide an additional mouse model for GPS, and highlight the potentially confounding effect of background spontaneous mutation events in well-characterized mouse strains. PMID:26950939

  9. Spontaneous 8bp Deletion in Nbeal2 Recapitulates the Gray Platelet Syndrome in Mice.

    Directory of Open Access Journals (Sweden)

    Kärt Tomberg

    Full Text Available During the analysis of a whole genome ENU mutagenesis screen for thrombosis modifiers, a spontaneous 8 base pair (bp deletion causing a frameshift in exon 27 of the Nbeal2 gene was identified. Though initially considered as a plausible thrombosis modifier, this Nbeal2 mutation failed to suppress the synthetic lethal thrombosis on which the original ENU screen was based. Mutations in NBEAL2 cause Gray Platelet Syndrome (GPS, an autosomal recessive bleeding disorder characterized by macrothrombocytopenia and gray-appearing platelets due to lack of platelet alpha granules. Mice homozygous for the Nbeal2 8 bp deletion (Nbeal2gps/gps exhibit a phenotype similar to human GPS, with significantly reduced platelet counts compared to littermate controls (p = 1.63 x 10-7. Nbeal2gps/gps mice also have markedly reduced numbers of platelet alpha granules and an increased level of emperipolesis, consistent with previously characterized mice carrying targeted Nbeal2 null alleles. These findings confirm previous reports, provide an additional mouse model for GPS, and highlight the potentially confounding effect of background spontaneous mutation events in well-characterized mouse strains.

  10. Translational control of TWIST1 expression in MCF-10A cell lines recapitulating breast cancer progression

    DEFF Research Database (Denmark)

    Nairismägi, Maarja-Liisa; Vislovukh, Andrii; Meng, Q

    2012-01-01

    and EMT, we found TWIST1 to be upregulated during EMT and downregulated early in carcinogenesis. The TWIST1 3′UTR contains putative regulatory elements, including miRNA target sites and two cytoplasmic polyadenylation elements (CPE). We found that miR-580, CPEB1, and CPEB2 act as negative regulators...

  11. Homeobox gene expression in adult dorsal root ganglia: Is regeneration a recapitulation of development?

    NARCIS (Netherlands)

    Vogelaar, C.F.

    2003-01-01

    Neurons of the peripheral nervous system are able to regenerate their peripheral axons after injury, leading to complete recovery of sensory and motor function. The sciatic nerve crush model is frequently used to study peripheral nerve regeneration. Sensory neurons in the dorsal root ganglia (DRGs)

  12. Clonal selection in xenografted TAM recapitulates the evolutionary process of myeloid leukemia in Down syndrome.

    Science.gov (United States)

    Saida, Satoshi; Watanabe, Ken-ichiro; Sato-Otsubo, Aiko; Terui, Kiminori; Yoshida, Kenichi; Okuno, Yusuke; Toki, Tsutomu; Wang, RuNan; Shiraishi, Yuichi; Miyano, Satoru; Kato, Itaru; Morishima, Tatsuya; Fujino, Hisanori; Umeda, Katsutsugu; Hiramatsu, Hidefumi; Adachi, Souichi; Ito, Etsuro; Ogawa, Seishi; Ito, Mamoru; Nakahata, Tatsutoshi; Heike, Toshio

    2013-05-23

    Transient abnormal myelopoiesis (TAM) is a clonal preleukemic disorder that progresses to myeloid leukemia of Down syndrome (ML-DS) through the accumulation of genetic alterations. To investigate the mechanism of leukemogenesis in this disorder, a xenograft model of TAM was established using NOD/Shi-scid, interleukin (IL)-2Rγ(null) mice. Serial engraftment after transplantation of cells from a TAM patient who developed ML-DS a year later demonstrated their self-renewal capacity. A GATA1 mutation and no copy number alterations (CNAs) were detected in the primary patient sample by conventional genomic sequencing and CNA profiling. However, in serial transplantations, engrafted TAM-derived cells showed the emergence of divergent subclones with another GATA1 mutation and various CNAs, including a 16q deletion and 1q gain, which are clinically associated with ML-DS. Detailed genomic analysis identified minor subclones with a 16q deletion or this distinct GATA1 mutation in the primary patient sample. These results suggest that genetically heterogeneous subclones with varying leukemia-initiating potential already exist in the neonatal TAM phase, and ML-DS may develop from a pool of such minor clones through clonal selection. Our xenograft model of TAM may provide unique insight into the evolutionary process of leukemia.

  13. Phage morphology recapitulates phylogeny: the comparative genomics of a new group of myoviruses.

    Directory of Open Access Journals (Sweden)

    André M Comeau

    Full Text Available Among dsDNA tailed bacteriophages (Caudovirales, members of the Myoviridae family have the most sophisticated virion design that includes a complex contractile tail structure. The Myoviridae generally have larger genomes than the other phage families. Relatively few "dwarf" myoviruses, those with a genome size of less than 50 kb such as those of the Mu group, have been analyzed in extenso. Here we report on the genome sequencing and morphological characterization of a new group of such phages that infect a diverse range of Proteobacteria, namely Aeromonas salmonicida phage 56, Vibrio cholerae phages 138 and CP-T1, Bdellovibrio phage φ1422, and Pectobacterium carotovorum phage ZF40. This group of dwarf myoviruses shares an identical virion morphology, characterized by usually short contractile tails, and have genome sizes of approximately 45 kb. Although their genome sequences are variable in their lysogeny, replication, and host adaption modules, presumably reflecting differing lifestyles and hosts, their structural and morphogenesis modules have been evolutionarily constrained by their virion morphology. Comparative genomic analysis reveals that these phages, along with related prophage genomes, form a new coherent group within the Myoviridae. The results presented in this communication support the hypothesis that the diversity of phages may be more structured than generally believed and that the innumerable phages in the biosphere all belong to discrete lineages or families.

  14. Does the peritumoral stroma of basal cell carcinoma recapitulate the follicular connective tissue sheath?

    Science.gov (United States)

    Sellheyer, Klaus; Krahl, Dieter

    2011-07-01

    There are compelling embryologic and anatomic relationships within adnexal tumors. However, these are mostly perceived within the epithelial component while the stromal component of the tumors is frequently overlooked. In postnatal skin, nestin is almost exclusively expressed in the perifollicular mesenchyme. This study examines the expression of this neuroepithelial stem cell protein in trichoblastoma/trichoepithelioma and in basal cell carcinoma (BCC), which is increasingly being viewed as follicular in nature. We employed standard immunohistochemical methods with three different antibodies to examine the expression of nestin in 25 BCCs and compared the staining pattern with that of 7 trichoblastomas and 11 trichoepitheliomas. Nestin is expressed in the peritumoral stroma of all tumors examined and is limited to the immediate layer of mesenchymal cells surrounding the tumor epithelium. In BCC, nestin-immunoreactive cells are found as a sheath of thin, spindled fibroblasts, while reactive cells are plump in trichoepitheliomas/trichoblastomas. We postulate that the peritumoral stroma of BCC imitates the perifollicular connective tissue sheath, while in contrast that of trichoepithelioma/trichoblastoma is similar to the papillary and immediate peripapillary follicular mesenchyme. Further functional and animal experimental studies are needed to test this hypothesis. Copyright © 2011 John Wiley & Sons A/S.

  15. Epithelial self-healing is recapitulated by a 3D biomimetic E-cadherin junction.

    Science.gov (United States)

    Cohen, Daniel J; Gloerich, Martijn; Nelson, W James

    2016-12-20

    Epithelial monolayers undergo self-healing when wounded. During healing, cells collectively migrate into the wound site, and the converging tissue fronts collide and form a stable interface. To heal, migrating tissues must form cell-cell adhesions and reorganize from the front-rear polarity characteristic of cell migration to the apical-basal polarity of an epithelium. However, identifying the "stop signal" that induces colliding tissues to cease migrating and heal remains an open question. Epithelial cells form integrin-based adhesions to the basal extracellular matrix (ECM) and E-cadherin-mediated cell-cell adhesions on the orthogonal, lateral surfaces between cells. Current biological tools have been unable to probe this multicellular 3D interface to determine the stop signal. We addressed this problem by developing a unique biointerface that mimicked the 3D organization of epithelial cell adhesions. This "minimal tissue mimic" (MTM) comprised a basal ECM substrate and a vertical surface coated with purified extracellular domain of E-cadherin, and was designed for collision with the healing edge of an epithelial monolayer. Three-dimensional imaging showed that adhesions formed between cells, and the E-cadherin-coated MTM resembled the morphology and dynamics of native epithelial cell-cell junctions and induced the same polarity transition that occurs during epithelial self-healing. These results indicate that E-cadherin presented in the proper 3D context constitutes a minimum essential stop signal to induce self-healing. That the Ecad:Fc MTM stably integrated into an epithelial tissue and reduced migration at the interface suggests that this biointerface is a complimentary approach to existing tissue-material interfaces.

  16. Epithelial self-healing is recapitulated by a 3D biomimetic E-cadherin junction

    OpenAIRE

    Cohen, Daniel J.; Gloerich, Martijn; Nelson, W. James

    2016-01-01

    Epithelial monolayers undergo self-healing when wounded. During healing, cells collectively migrate into the wound site, and the converging tissue fronts collide and form a stable interface. To heal, migrating tissues must form cell-cell adhesions and reorganize from the front-rear polarity characteristic of cell migration to the apicalbasal polarity of an epithelium. However, identifying the "stop signal" that induces colliding tissues to cease migrating and heal remains an open question. Ep...

  17. Pregnane X Receptor-Humanized Mice Recapitulate Gender Differences in Ethanol Metabolism but Not Hepatotoxicity.

    Science.gov (United States)

    Spruiell, Krisstonia; Gyamfi, Afua A; Yeyeodu, Susan T; Richardson, Ricardo M; Gonzalez, Frank J; Gyamfi, Maxwell A

    2015-09-01

    Both human and rodent females are more susceptible to developing alcoholic liver disease following chronic ethanol (EtOH) ingestion. However, little is known about the relative effects of acute EtOH exposure on hepatotoxicity in female versus male mice. The nuclear receptor pregnane X receptor (PXR; NR1I2) is a broad-specificity sensor with species-specific responses to toxic agents. To examine the effects of the human PXR on acute EtOH toxicity, the responses of male and female PXR-humanized (hPXR) transgenic mice administered oral binge EtOH (4.5 g/kg) were analyzed. Basal differences were observed between hPXR males and females in which females expressed higher levels of two principal enzymes responsible for EtOH metabolism, alcohol dehydrogenase 1 and aldehyde dehydrogenase 2, and two key mediators of hepatocyte replication and repair, cyclin D1 and proliferating cell nuclear antigen. EtOH ingestion upregulated hepatic estrogen receptor α, cyclin D1, and CYP2E1 in both genders, but differentially altered lipid and EtOH metabolism. Consistent with higher basal levels of EtOH-metabolizing enzymes, blood EtOH was more rapidly cleared in hPXR females. These factors combined to provide greater protection against EtOH-induced liver injury in female hPXR mice, as revealed by markers for liver damage, lipid peroxidation, and endoplasmic reticulum stress. These results indicate that female hPXR mice are less susceptible to acute binge EtOH-induced hepatotoxicity than their male counterparts, due at least in part to the relative suppression of cellular stress and enhanced expression of enzymes involved in both EtOH metabolism and hepatocyte proliferation and repair in hPXR females. U.S. Government work not protected by U.S. copyright.

  18. The PRRT2 knockout mouse recapitulates the neurological diseases associated with PRRT2 mutations.

    Science.gov (United States)

    Michetti, Caterina; Castroflorio, Enrico; Marchionni, Ivan; Forte, Nicola; Sterlini, Bruno; Binda, Francesca; Fruscione, Floriana; Baldelli, Pietro; Valtorta, Flavia; Zara, Federico; Corradi, Anna; Benfenati, Fabio

    2017-03-01

    Heterozygous and rare homozygous mutations in PRoline-Rich Transmembrane protein 2 (PRRT2) underlie a group of paroxysmal disorders including epilepsy, kinesigenic dyskinesia episodic ataxia and migraine. Most of the mutations lead to impaired PRRT2 expression and/or function. Recently, an important role for PRTT2 in the neurotransmitter release machinery, brain development and synapse formation has been uncovered. In this work, we have characterized the phenotype of a mouse in which the PRRT2 gene has been constitutively inactivated (PRRT2 KO). β-galactosidase staining allowed to map the regional expression of PRRT2 that was more intense in the cerebellum, hindbrain and spinal cord, while it was localized to restricted areas in the forebrain. PRRT2 KO mice are normal at birth, but display paroxysmal movements at the onset of locomotion that persist in the adulthood. In addition, adult PRRT2 KO mice present abnormal motor behaviors characterized by wild running and jumping in response to audiogenic stimuli that are ineffective in wild type mice and an increased sensitivity to the convulsive effects of pentylentetrazol. Patch-clamp electrophysiology in hippocampal and cerebellar slices revealed specific effects in the cerebellum, where PRRT2 is highly expressed, consisting in a higher excitatory strength at parallel fiber-Purkinje cell synapses during high frequency stimulation. The results show that the PRRT2 KO mouse reproduces the motor paroxysms present in the human PRRT2-linked pathology and can be proposed as an experimental model for the study of the pathogenesis of the disease as well as for testing personalized therapeutic approaches. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  19. Giant hub Src and Syk tyrosine kinase thermodynamic profiles recapitulate evolution

    Science.gov (United States)

    Phillips, J. C.

    2017-10-01

    Thermodynamic scaling theory, previously applied mainly to small proteins, here analyzes quantitative evolution of the titled functional network giant hub enzymes. The broad domain structure identified homologically is confirmed hydropathically using amino acid sequences only. The most surprising results concern the evolution of the tyrosine kinase globular surface roughness from avians to mammals, which is first order, compared to the evolution within mammals from rodents to humans, which is second order. The mystery of the unique amide terminal region of proto oncogene tyrosine protein kinase is resolved by the discovery there of a rare hydroneutral septad targeting cluster, which is paralleled by an equally rare octad catalytic cluster in tyrosine kinase in humans and a few other species (cat and dog). These results, which go far towards explaining why these proteins are among the largest giant hubs in protein interaction networks, use no adjustable parameters.

  20. CRISPR/Cas9-mediated Dax1 knockout in the monkey recapitulates human AHC-HH.

    Science.gov (United States)

    Kang, Yu; Zheng, Bo; Shen, Bin; Chen, Yongchang; Wang, Lei; Wang, Jianying; Niu, Yuyu; Cui, Yiqiang; Zhou, Jiankui; Wang, Hong; Guo, Xuejiang; Hu, Bian; Zhou, Qi; Sha, Jiahao; Ji, Weizhi; Huang, Xingxu

    2015-12-20

    Mutations in the DAX1 locus cause X-linked adrenal hypoplasia congenita (AHC) and hypogonadotropic hypogonadism (HH), which manifest with primary adrenal insufficiency and incomplete or absent sexual maturation, respectively. The associated defects in spermatogenesis can range from spermatogenic arrest to Sertoli cell only syndrome. Conclusions from Dax1 knockout mouse models provide only limited insight into AHC/HH disease mechanisms, because mouse models exhibit more extensive abnormalities in testicular development, including disorganized and incompletely formed testis cords with decreased number of peritubular myoid cells and male-to-female sex reversal. We previously reported successful clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9)-mediated genome targeting in cynomolgus monkeys. Here, we describe a male fetal monkey in which targeted genome editing using CRISPR/Cas9 produced Dax1-null mutations in most somatic tissues and in the gonads. This DAX1-deficient monkey displayed defects in adrenal gland development and abnormal testis architecture with small cords, expanded blood vessels and extensive fibrosis. Sertoli cell formation was not affected. This phenotype strongly resembles findings in human patients with AHC-HH caused by mutations in DAX1. We further detected upregulation of Wnt/β-catenin-VEGF signaling in the fetal Dax1-deficient testis, suggesting abnormal activation of signaling pathways in the absence of DAX1 as one mechanism of AHC-HH. Our study reveals novel insight into the role of DAX1 in HH and provides proof-of-principle for the generation of monkey models of human disease via CRISPR/Cas9-mediated gene targeting. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. A 3D Microfluidic Model to Recapitulate Cancer Cell Migration and Invasion

    Directory of Open Access Journals (Sweden)

    Yi-Chin Toh

    2018-04-01

    Full Text Available We have developed a microfluidic-based culture chip to simulate cancer cell migration and invasion across the basement membrane. In this microfluidic chip, a 3D microenvironment is engineered to culture metastatic breast cancer cells (MX1 in a 3D tumor model. A chemo-attractant was incorporated to stimulate motility across the membrane. We validated the usefulness of the chip by tracking the motilities of the cancer cells in the system, showing them to be migrating or invading (akin to metastasis. It is shown that our system can monitor cell migration in real time, as compare to Boyden chambers, for example. Thus, the chip will be of interest to the drug-screening community as it can potentially be used to monitor the behavior of cancer cell motility, and, therefore, metastasis, in the presence of anti-cancer drugs.

  2. A systematic review on in vitro 3D bone metastases models: A new horizon to recapitulate the native clinical scenario?

    Science.gov (United States)

    Salamanna, Francesca; Contartese, Deyanira; Maglio, Melania; Fini, Milena

    2016-07-12

    While the skeleton is not the only organ where metastasis can occur, it is one of the preferred sites, with a significant impact in patients' quality of life. With the aim of delineating the cellular and molecular mechanisms of bone metastasis, numerous studies have been employed to identify any contributing factors that trigger cancer progression. One of the major limitations of studying cancer-bone metastasis is the multifaceted nature of the native bone environment and the lack of reliable, simple, and not expensive models that strictly mimic the biological processes occurring in vivo allowing a correct translation of results. Currently, with the growing acceptance of in vitro models as effective tools for studying cancer biology, three-dimensional (3D) models have emerged as a compromise between two-dimensional cultures of isolated cancer cells and the complexity of human cancer xenografts in immunocompromised animal hosts. This descriptive systematic literature review summarizes the current status of advanced and alternative 3D in vitro bone metastases models. We have also reviewed the strategies employed by researchers to set-up these models with special reference to recent promising developments trying to better replicate the complexity and heterogeneity of a human metastasis in situ, with an outlook at their use in medicine. All these aspects will greatly contribute to the existing knowledge on bone metastases, providing a specific link to clinical scenarios and thus making 3D in vitro bone metastasis models an attractive tool for multidisciplinary experts.

  3. Carcinogen-Induced Hepatic Tumors in KLF6+/- Mice Recapitulate Aggressive Human Hepatocellular Carcinoma Associated with p53 Pathway Deregulation

    NARCIS (Netherlands)

    Tarocchi, Mirko; Hannivoort, Rebekka; Hoshida, Yujin; Lee, Ursula E.; Vetter, Diana; Narla, Goutham; Villanueva, Augusto; Oren, Moshe; Llovet, Josep M.; Friedman, Scott L.

    Inactivation of KLF6 is common in hepatocellular carcinoma (HCC) associated with hepatitis C virus (HCV) infection, thereby abrogating its normal antiproliferative activity in liver cells. The aim of the study was to evaluate the impact of KLF6 depletion on human HCC and experimental

  4. Optimization of a murine and human tissue model to recapitulate dermal and pulmonary features of systemic sclerosis.

    Directory of Open Access Journals (Sweden)

    Tomoya Watanabe

    Full Text Available The murine bleomycin (BLM-induced fibrosis model is the most widely used in systemic sclerosis (SSc studies. It has been reported that systemic delivery of BLM via continuous diffusion from subcutaneously implanted osmotic minipumps can cause fibrosis of the skin, lungs, and other internal organs. However, the mouse strain, dosage of BLM, administration period, and additional important features differ from one report to the next. In this study, by employing the pump model in C57BL/6J mice, we show a dose-dependent increase in lung fibrosis by day 28 and a transient increase in dermal thickness. Dermal thickness and the level of collagen in skin treated with high-dose BLM was significantly higher than in skin treated with low dose BLM or vehicle. A reduction in the thickness of the adipose layer was noted in both high and low dose groups at earlier time points suggesting that the loss of the fat layer precedes the onset of fibrosis. High-dose BLM also induced dermal fibrosis and increased expression of fibrosis-associated genes ex vivo in human skin, thus confirming and extending the in vivo findings, and demonstrating that a human organ culture model can be used to assess the effect of BLM on skin. In summary, our findings suggest that the BLM pump model is an attractive model to analyze the underlying mechanisms of fibrosis and test the efficacy of potential therapies. However, the choice of mouse strain, duration of BLM administration and dose must be carefully considered when using this model.

  5. The orthotopic xenotransplant of human glioblastoma successfully recapitulates glioblastoma-microenvironment interactions in a non-immunosuppressed mouse model.

    Science.gov (United States)

    Garcia, Celina; Dubois, Luiz Gustavo; Xavier, Anna Lenice; Geraldo, Luiz Henrique; da Fonseca, Anna Carolina Carvalho; Correia, Ana Helena; Meirelles, Fernanda; Ventura, Grasiella; Romão, Luciana; Canedo, Nathalie Henriques Silva; de Souza, Jorge Marcondes; de Menezes, João Ricardo Lacerda; Moura-Neto, Vivaldo; Tovar-Moll, Fernanda; Lima, Flavia Regina Souza

    2014-12-08

    Glioblastoma (GBM) is the most common primary brain tumor and the most aggressive glial tumor. This tumor is highly heterogeneous, angiogenic, and insensitive to radio- and chemotherapy. Here we have investigated the progression of GBM produced by the injection of human GBM cells into the brain parenchyma of immunocompetent mice. Xenotransplanted animals were submitted to magnetic resonance imaging (MRI) and histopathological analyses. Our data show that two weeks after injection, the produced tumor presents histopathological characteristics recommended by World Health Organization for the diagnosis of GBM in humans. The tumor was able to produce reactive gliosis in the adjacent parenchyma, angiogenesis, an intense recruitment of macrophage and microglial cells, and presence of necrosis regions. Besides, MRI showed that tumor mass had enhanced contrast, suggesting a blood-brain barrier disruption. This study demonstrated that the xenografted tumor in mouse brain parenchyma develops in a very similar manner to those found in patients affected by GBM and can be used to better understand the biology of GBM as well as testing potential therapies.

  6. Histological evidence of oxidative stress and premature senescence in preterm premature rupture of the human fetal membranes recapitulated in vitro.

    Science.gov (United States)

    Menon, Ramkumar; Boldogh, Istvan; Hawkins, Hal K; Woodson, Michael; Polettini, Jossimara; Syed, Tariq Ali; Fortunato, Stephen J; Saade, George R; Papaconstantinou, John; Taylor, Robert N

    2014-06-01

    Preterm prelabor rupture of the membranes (pPROM) may lead to preterm births (PTBs). We investigated premature senescence of fetal membranes in women with pPROM and spontaneous PTB with intact membranes (PTBs, and term births. Term fetal membranes were exposed to cigarette smoke extract to induce oxidative stress. Western blots documented p-p53 and p-p38 MAPK. Transmission electron microscopy assessed cellular morphologic features in clinical and cigarette smoke extract-treated membranes. A total of 80% of pPROM cells and >60% of term cells were positive for all three senescence phenotype markers, and concentrations were higher than in PTBs (P PTBs. Histologic and biochemical resemblance of pPROM and term membranes suggests premature senescence of the membranes is a mechanistic feature in pPROM, and this can be phenocopied in an in vitro model. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  7. Cardiomyocytes Derived From Pluripotent Stem Cells Recapitulate Electrophysiological Characteristics of an Overlap Syndrome of Cardiac Sodium Channel Disease

    NARCIS (Netherlands)

    Davis, Richard P.; Casini, Simona; van den Berg, Cathelijne W.; Hoekstra, Maaike; Remme, Carol Ann; Dambrot, Cheryl; Salvatori, Daniela; Ward-van Oostwaard, Dorien; Wilde, Arthur A. M.; Bezzina, Connie R.; Verkerk, Arie O.; Freund, Christian; Mummery, Christine L.

    2012-01-01

    Background-Pluripotent stem cells (PSCs) offer a new paradigm for modeling genetic cardiac diseases, but it is unclear whether mouse and human PSCs can truly model both gain-and loss-of-function genetic disorders affecting the Na+ current (I-Na) because of the immaturity of the PSC-derived

  8. Phylogeographical Analysis on Squalidus argentatus Recapitulates Historical Landscapes and Drainage Evolution on the Island of Taiwan and Mainland China

    Directory of Open Access Journals (Sweden)

    Hung-Du Lin

    2012-01-01

    Full Text Available Phylogeographical analyses on Squalidus argentatus samples from thirteen localities within mainland China and Taiwan were conducted for biogeographic studies, as their dispersal strictly depends on geological evolution of the landmasses. A total of 95 haplotypes were genotyped for mtDNA cyt b gene in 160 specimens from nine river systems. Relatively high levels of haplotype diversity (h = 0.984 and low levels of nucleotide diversity (π = 0.020 were detected in S. argentatus. Two major phylogenetic haplotype groups, A and B, were revealed via phylogenetic analysis. The degree of intergroup divergence (3.96% indicates that these groups diverged about 4.55 myr (million years ago. Haplotype network and population analyses indicated significant genetic structure (FST = 0.775, largely concordant with the geographical location of the populations. According to SAMOVA analysis, we divided these populations into four units: Yangtze-Pearl, Qiantang-Minjiang, Jiulong-Beijiang and Taiwan groups. Mismatch distribution analysis, neutrality tests and Bayesian skyline plots indicated a significant population expansion for lineage A and B, approximately dated 0.35 and 0.04 myr ago, respectively. We found strong geographical organization of the haplotype clades across different geographic scales that can be explained by episodes of dispersal and population expansion followed by population fragmentation and restricted gene flow.

  9. Anti-proteinase 3 anti-neutrophil cytoplasm autoantibodies recapitulate systemic vasculitis in mice with a humanized immune system.

    Directory of Open Access Journals (Sweden)

    Mark A Little

    Full Text Available Evidence is lacking for direct pathogenicity of human anti-proteinase-3 (PR3 antibodies in development of systemic vasculitis and granulomatosis with polyangiitis (GPA, Wegener's granulomatosis. Progress in study of these antibodies in rodents has been hampered by lack of PR3 expression on murine neutrophils, and by different Fc-receptor affinities for IgG across species. Therefore, we tested whether human anti-PR3 antibodies can induce acute vasculitis in mice with a human immune system. Chimeric mice were generated by injecting human haematopoietic stem cells into irradiated NOD-scid-IL2Rγ⁻/⁻ mice. Matched chimera mice were treated with human IgG from patients with: anti-PR3 positive renal and lung vasculitis; patients with non-vasculitic renal disease; or healthy controls. Six-days later, 39% of anti-PR3 treated mice had haematuria, compared with none of controls. There was punctate bleeding on the surface of lungs of anti-PR3 treated animals, with histological evidence of vasculitis and haemorrhage. Anti-PR3 treated mice had mild pauci-immune proliferative glomerulonephritis, with infiltration of human and mouse leukocytes. In 3 mice (17% more severe glomerular injury was present. There were no glomerular changes in controls. Human IgG from patients with anti-PR3 autoantibodies is therefore pathogenic. This model of anti-PR3 antibody-mediated vasculitis may be useful in dissecting mechanisms of microvascular injury.

  10. A mouse model for fucosidosis recapitulates storage pathology and neurological features of the milder form of the human disease

    Directory of Open Access Journals (Sweden)

    Heike Wolf

    2016-09-01

    Full Text Available Fucosidosis is a rare lysosomal storage disorder caused by the inherited deficiency of the lysosomal hydrolase α-L-fucosidase, which leads to an impaired degradation of fucosylated glycoconjugates. Here, we report the generation of a fucosidosis mouse model, in which the gene for lysosomal α-L-fucosidase (Fuca1 was disrupted by gene targeting. Homozygous knockout mice completely lack α-L-fucosidase activity in all tested organs leading to highly elevated amounts of the core-fucosylated glycoasparagine Fuc(α1,6-GlcNAc(β1-N-Asn and, to a lesser extent, other fucosylated glycoasparagines, which all were also partially excreted in urine. Lysosomal storage pathology was observed in many visceral organs, such as in the liver, kidney, spleen and bladder, as well as in the central nervous system (CNS. On the cellular level, storage was characterized by membrane-limited cytoplasmic vacuoles primarily containing water-soluble storage material. In the CNS, cellular alterations included enlargement of the lysosomal compartment in various cell types, accumulation of secondary storage material and neuroinflammation, as well as a progressive loss of Purkinje cells combined with astrogliosis leading to psychomotor and memory deficits. Our results demonstrate that this new fucosidosis mouse model resembles the human disease and thus will help to unravel underlying pathological processes. Moreover, this model could be utilized to establish diagnostic and therapeutic strategies for fucosidosis.

  11. Recapitulation of spinal motor neuron-specific disease phenotypes in a human cell model of spinal muscular atrophy

    Institute of Scientific and Technical Information of China (English)

    Zhi-Bo Wang; Xiaoqing Zhang; Xue-Jun Li

    2013-01-01

    Establishing human cell models of spinal muscular atrophy (SMA) to mimic motor neuron-specific phenotypes holds the key to understanding the pathogenesis of this devastating disease.Here,we developed a closely representative cell model of SMA by knocking down the disease-determining gene,survival motor neuron (SMN),in human embryonic stem cells (hESCs).Our study with this cell model demonstrated that knocking down of SMN does not interfere with neural induction or the initial specification of spinal motor neurons.Notably,the axonal outgrowth of spinal motor neurons was significantly impaired and these disease-mimicking neurons subsequently degenerated.Furthermore,these disease phenotypes were caused by SMN-full length (SMN-FL) but not SMN-A7 (lacking exon 7)knockdown,and were specific to spinal motor neurons.Restoring the expression of SMN-FL completely ameliorated all of the disease phenotypes,including specific axonal defects and motor neuron loss.Finally,knockdown of SMNFL led to excessive mitochondrial oxidative stress in human motor neuron progenitors.The involvement of oxidative stress in the degeneration of spinal motor neurons in the SMA cell model was further confirmed by the administration of N-acetylcysteine,a potent antioxidant,which prevented disease-related apoptosis and subsequent motor neuron death.Thus,we report here the successful establishment of an hESC-based SMA model,which exhibits disease gene isoform specificity,cell type specificity,and phenotype reversibility.Our model provides a unique paradigm for studying how motor neurons specifically degenerate and highlights the potential importance of antioxidants for the treatment of SMA.

  12. A mouse model for fucosidosis recapitulates storage pathology and neurological features of the milder form of the human disease

    DEFF Research Database (Denmark)

    Wolf, Heike; Damme, Markus; Stroobants, Stijn

    2016-01-01

    Fucosidosis is a rare lysosomal storage disorder caused by the inherited deficiency of the lysosomal hydrolase α-L-fucosidase, which leads to an impaired degradation of fucosylated glycoconjugates. Here we report the generation of a fucosidosis mouse model, in which the gene for lysosomal α-L-fuc...

  13. An allosteric gating model recapitulates the biophysical properties of IK,L expressed in mouse vestibular type I hair cells.

    Science.gov (United States)

    Spaiardi, Paolo; Tavazzani, Elisa; Manca, Marco; Milesi, Veronica; Russo, Giancarlo; Prigioni, Ivo; Marcotti, Walter; Magistretti, Jacopo; Masetto, Sergio

    2017-11-01

    Vestibular type I and type II hair cells and their afferent fibres send information to the brain regarding the position and movement of the head. The characteristic feature of type I hair cells is the expression of a low-voltage-activated outward rectifying K + current, I K,L , whose biophysical properties and molecular identity are still largely unknown. In vitro, the afferent nerve calyx surrounding type I hair cells causes unstable intercellular K + concentrations, altering the biophysical properties of I K,L . We found that in the absence of the calyx, I K,L in type I hair cells exhibited unique biophysical activation properties, which were faithfully reproduced by an allosteric channel gating scheme. These results form the basis for a molecular and pharmacological identification of I K,L . Type I and type II hair cells are the sensory receptors of the mammalian vestibular epithelia. Type I hair cells are characterized by their basolateral membrane being enveloped in a single large afferent nerve terminal, named the calyx, and by the expression of a low-voltage-activated outward rectifying K + current, I K,L . The biophysical properties and molecular profile of I K,L are still largely unknown. By using the patch-clamp whole-cell technique, we examined the voltage- and time-dependent properties of I K,L in type I hair cells of the mouse semicircular canal. We found that the biophysical properties of I K,L were affected by an unstable K + equilibrium potential (V eq K + ). Both the outward and inward K + currents shifted V eq K + consistent with K + accumulation or depletion, respectively, in the extracellular space, which we attributed to a residual calyx attached to the basolateral membrane of the hair cells. We therefore optimized the hair cell dissociation protocol in order to isolate mature type I hair cells without their calyx. In these cells, the uncontaminated I K,L showed a half-activation at -79.6 mV and a steep voltage dependence (2.8 mV). I K,L also showed complex activation and deactivation kinetics, which we faithfully reproduced by an allosteric channel gating scheme where the channel is able to open from all (five) closed states. The 'early' open states substantially contribute to I K,L activation at negative voltages. This study provides the first complete description of the 'native' biophysical properties of I K,L in adult mouse vestibular type I hair cells. © 2017 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.

  14. Simian varicella virus infection of rhesus macaques recapitulates essential features of varicella zoster virus infection in humans.

    Directory of Open Access Journals (Sweden)

    Ilhem Messaoudi

    2009-11-01

    Full Text Available Simian varicella virus (SVV, the etiologic agent of naturally occurring varicella in primates, is genetically and antigenically closely related to human varicella zoster virus (VZV. Early attempts to develop a model of VZV pathogenesis and latency in nonhuman primates (NHP resulted in persistent infection. More recent models successfully produced latency; however, only a minority of monkeys became viremic and seroconverted. Thus, previous NHP models were not ideally suited to analyze the immune response to SVV during acute infection and the transition to latency. Here, we show for the first time that intrabronchial inoculation of rhesus macaques with SVV closely mimics naturally occurring varicella (chickenpox in humans. Infected monkeys developed varicella and viremia that resolved 21 days after infection. Months later, viral DNA was detected only in ganglia and not in non-ganglionic tissues. Like VZV latency in human ganglia, transcripts corresponding to SVV ORFs 21, 62, 63 and 66, but not ORF 40, were detected by RT-PCR. In addition, as described for VZV, SVV ORF 63 protein was detected in the cytoplasm of neurons in latently infected monkey ganglia by immunohistochemistry. We also present the first in depth analysis of the immune response to SVV. Infected animals produced a strong humoral and cell-mediated immune response to SVV, as assessed by immunohistology, serology and flow cytometry. Intrabronchial inoculation of rhesus macaques with SVV provides a novel model to analyze viral and immunological mechanisms of VZV latency and reactivation.

  15. Craniosynostosis of coronal suture in Twist1+/- mice occurs through endochondral ossification recapitulating the physiological closure of posterior frontal suture

    Directory of Open Access Journals (Sweden)

    Bjorn eBehr

    2011-07-01

    Full Text Available Craniosynostosis, the premature closure of cranial suture, is a pathologic condition that affects 1/2000 live births. Saethre-Chotzen syndrome is a genetic condition characterized by craniosynostosis. The Saethre-Chotzen syndrome, which is defined by loss-of-function mutations in the TWIST gene, is the second most prevalent craniosynostosis. Although much of the genetics and phenotypes in craniosynostosis syndromes is understood, less is known about the underlying ossification mechanism during suture closure. We have previously demonstrated that physiological closure of the posterior frontal (PF suture occurs through endochondral ossification. Moreover, we revealed that antagonizing canonical Wnt signaling in the sagittal suture leads to endochondral ossification of the suture mesenchyme and sagittal synostosis, presumably by inhibiting Twist1. Classic Saethre-Chotzen syndrome is characterized by coronal synostosis, and the haploinsufficient Twist1+/- mice represents a suitable model for studying this syndrome. Thus, we seeked to understand the underlying ossification process in coronal craniosynostosis in Twist1+/- mice. Our data indicate that coronal suture closure in Twist1+/- mice occurs between postnatal day 9 to 13 by endochondral ossification, as shown by histology, gene expression analysis and immunohistochemistry. In conclusion, this study reveals that coronal craniosynostosis in Twist1+/- mice occurs through endochondral ossification. Moreover, it suggests that haploinsufficency of Twist1 gene, a target of canonical Wnt-signaling, and inhibitor of chondrogenesis, mimics conditions of inactive canonical Wnt-signaling leading to craniosynostosis.

  16. Neuropsychology and cognitive neuroscience in the fMRI era: A recapitulation of localizationist and connectionist views.

    Science.gov (United States)

    Sutterer, Matthew J; Tranel, Daniel

    2017-11-01

    We highlight the past 25 years of cognitive neuroscience and neuropsychology, focusing on the impact to the field of the introduction in 1992 of functional MRI (fMRI). We reviewed the past 25 years of literature in cognitive neuroscience and neuropsychology, focusing on the relation and interplay of fMRI studies and studies utilizing the "lesion method" in human participants with focal brain damage. Our review highlights the state of localist/connectionist research debates in cognitive neuroscience and neuropsychology circa 1992, and details how the introduction of fMRI into the field at that time catalyzed a new wave of efforts to map complex human behavior to specific brain regions. This, in turn, eventually evolved into many studies that focused on networks and connections between brain areas, culminating in recent years with large-scale investigations such as the Human Connectome Project. We argue that throughout the past 25 years, neuropsychology-and more precisely, the "lesion method" in humans-has continued to play a critical role in arbitrating conclusions and theories derived from inferred patterns of local brain activity or wide-spread connectivity from functional imaging approaches. We conclude by highlighting the future for neuropsychology in the context of an increasingly complex methodological armamentarium. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  17. Bioactive poly(ethylene glycol) hydrogels to recapitulate the HSC niche and facilitate HSC expansion in culture.

    Science.gov (United States)

    Cuchiara, Maude L; Coşkun, Süleyman; Banda, Omar A; Horter, Kelsey L; Hirschi, Karen K; West, Jennifer L

    2016-04-01

    Hematopoietic stem cells (HSCs) have been used therapeutically for decades, yet their widespread clinical use is hampered by the inability to expand HSCs successfully in vitro. In culture, HSCs rapidly differentiate and lose their ability to self-renew. We hypothesize that by mimicking aspects of the bone marrow microenvironment in vitro we can better control the expansion and differentiation of these cells. In this work, derivatives of poly(ethylene glycol) diacrylate hydrogels were used as a culture substrate for hematopoietic stem and progenitor cell (HSPC) populations. Key HSC cytokines, stem cell factor (SCF) and interferon-γ (IFNγ), as well as the cell adhesion ligands RGDS and connecting segment 1 were covalently immobilized onto the surface of the hydrogels. With the use of SCF and IFNγ, we observed significant expansion of HSPCs, ∼97 and ∼104 fold respectively, while maintaining c-kit(+) lin(-) and c-kit(+) Sca1(+) lin(-) (KSL) populations and the ability to form multilineage colonies after 14 days. HSPCs were also encapsulated within degradable poly(ethylene glycol) hydrogels for three-dimensional culture. After expansion in hydrogels, ∼60% of cells were c-kit(+), demonstrating no loss in the proportion of these cells over the 14 day culture period, and ∼50% of colonies formed were multilineage, indicating that the cells retained their differentiation potential. The ability to tailor and use this system to support HSC growth could have implications on the future use of HSCs and other blood cell types in a clinical setting. © 2015 Wiley Periodicals, Inc.

  18. Low dose rectal inoculation of rhesus macaques by SIV smE660 or SIVmac251 recapitulates

    Energy Technology Data Exchange (ETDEWEB)

    Hraber, Peter [Los Alamos National Laboratory; Giorgi, Elena E [Los Alamos National Laboratory; Keele, Brandon [UNIV OF ALABAMA; Li, Hui [UNIV OF ALABAMA; Learn, Gerald [UNIV OF ALABAMA

    2008-01-01

    We recently developed a novel strategy to identify transmitted HIV-1 genomes in acutely infected humans using single-genome amplification and a model of random virus evolution. Here, we used this approach to determine the molecular features of simian immunodeficiency virus (SIV) transmission in 18 experimentally infected Indian rhesus macaques. Animals were inoculated intrarectally (i.r.) or intravenously (i.v.) with stocks of SIVmac251 or SIVsmE660 that exhibited sequence diversity typical of early-chronic HIV-1 infection. 987 full-length SIV env sequences (median of 48 per animal) were determined from plasma virion RNA 1--5 wk after infection. i.r. inoculation was followed by productive infection by one or a few viruses (median 1; range 1--5) that diversified randomly with near starlike phylogeny and a Poisson distribution of mutations. Consensus viral sequences from ramp-up and peak viremia were identical to viruses found in the inocula or differed from them by only one or a few nucleotides, providing direct evidence that early plasma viral sequences coalesce to transmitted/founder viruses. i.v. infection was >2,000-fold more efficient than i.r. infection, and viruses transmitted by either route represented the full genetic spectra of the inocula. These findings identify key similarities in mucosal transmission and early diversification between SIV and HIV-1, and thus validate the SIV-macaque mucosal infection model for HIV-1 vaccine and microbicide research.

  19. Online Social Support for Young People: Does It Recapitulate In-person Social Support; Can It Help?

    Science.gov (United States)

    Cole, David A; Nick, Elizabeth A; Zelkowitz, Rachel L; Roeder, Kathryn M; Spinelli, Tawny

    2017-03-01

    As social media websites have grown in popularity, public concern about online victimization has grown as well; however, much less attention has focused on the possible beneficial effects of online social networks. If theory and research about in-person social networks pertain, then online social relationships may represent an important modern source of or vehicle for support. In a study of 231 undergraduates, three major findings emerged: (1) for people with weaker in-person social support, social media sites provide a source of social support that is less redundant of the social support they receive in person; (2) in ways that were not redundant of each other, both online and in-person social support were associated with lower levels of depression-related thoughts and feelings, and (3) the beneficial effects of online social support (like in-person social support) offset some of the adverse effects of peer victimization. The study suggests that augmenting social relations via strategic use of social media can enhance young people's social support systems in beneficial ways.

  20. Anti-proteinase 3 anti-neutrophil cytoplasm autoantibodies recapitulate systemic vasculitis in mice with a humanized immune system.

    LENUS (Irish Health Repository)

    Little, Mark A

    2012-01-01

    Evidence is lacking for direct pathogenicity of human anti-proteinase-3 (PR3) antibodies in development of systemic vasculitis and granulomatosis with polyangiitis (GPA, Wegener\\'s granulomatosis). Progress in study of these antibodies in rodents has been hampered by lack of PR3 expression on murine neutrophils, and by different Fc-receptor affinities for IgG across species. Therefore, we tested whether human anti-PR3 antibodies can induce acute vasculitis in mice with a human immune system. Chimeric mice were generated by injecting human haematopoietic stem cells into irradiated NOD-scid-IL2Rγ⁻\\/⁻ mice. Matched chimera mice were treated with human IgG from patients with: anti-PR3 positive renal and lung vasculitis; patients with non-vasculitic renal disease; or healthy controls. Six-days later, 39% of anti-PR3 treated mice had haematuria, compared with none of controls. There was punctate bleeding on the surface of lungs of anti-PR3 treated animals, with histological evidence of vasculitis and haemorrhage. Anti-PR3 treated mice had mild pauci-immune proliferative glomerulonephritis, with infiltration of human and mouse leukocytes. In 3 mice (17%) more severe glomerular injury was present. There were no glomerular changes in controls. Human IgG from patients with anti-PR3 autoantibodies is therefore pathogenic. This model of anti-PR3 antibody-mediated vasculitis may be useful in dissecting mechanisms of microvascular injury.

  1. A recapitulation of the Nearctic species of Centromerus Dahl (Araneida, Linyphiidae) with remarks on Tunagyna Debilis (Banks)

    NARCIS (Netherlands)

    Helsdingen, van P.J.

    1973-01-01

    In any new region the knowledge of the spider fauna, or of any other group of organisms, has to go through three successive stages. In the beginning there is a period of descriptive activity with many new species recorded and named, in the past usually by several authors independently. In the

  2. Integrating 4-d light-sheet imaging with interactive virtual reality to recapitulate developmental cardiac mechanics and physiology

    Science.gov (United States)

    Ding, Yichen; Yu, Jing; Abiri, Arash; Abiri, Parinaz; Lee, Juhyun; Chang, Chih-Chiang; Baek, Kyung In; Sevag Packard, René R.; Hsiai, Tzung K.

    2018-02-01

    There currently is a limited ability to interactively study developmental cardiac mechanics and physiology. We therefore combined light-sheet fluorescence microscopy (LSFM) with virtual reality (VR) to provide a hybrid platform for 3- dimensional (3-D) architecture and time-dependent cardiac contractile function characterization. By taking advantage of the rapid acquisition, high axial resolution, low phototoxicity, and high fidelity in 3-D and 4-D (3-D spatial + 1-D time or spectra), this VR-LSFM hybrid methodology enables interactive visualization and quantification otherwise not available by conventional methods such as routine optical microscopes. We hereby demonstrate multi-scale applicability of VR-LSFM to 1) interrogate skin fibroblasts interacting with a hyaluronic acid-based hydrogel, 2) navigate through the endocardial trabecular network during zebrafish development, and 3) localize gene therapy-mediated potassium channel expression in adult murine hearts. We further combined our batch intensity normalized segmentation (BINS) algorithm with deformable image registration (DIR) to interface a VR environment for the analysis of cardiac contraction. Thus, the VR-LSFM hybrid platform demonstrates an efficient and robust framework for creating a user-directed microenvironment in which we uncovered developmental cardiac mechanics and physiology with high spatiotemporal resolution.

  3. mRNA-Seq of single prostate cancer circulating tumor cells reveals recapitulation of gene expression and pathways found in prostate cancer.

    Directory of Open Access Journals (Sweden)

    Gordon M Cann

    Full Text Available Circulating tumor cells (CTC mediate metastatic spread of many solid tumors and enumeration of CTCs is currently used as a prognostic indicator of survival in metastatic prostate cancer patients. Some evidence suggests that it is possible to derive additional information about tumors from expression analysis of CTCs, but the technical difficulty of isolating and analyzing individual CTCs has limited progress in this area. To assess the ability of a new generation of MagSweeper to isolate intact CTCs for downstream analysis, we performed mRNA-Seq on single CTCs isolated from the blood of patients with metastatic prostate cancer and on single prostate cancer cell line LNCaP cells spiked into the blood of healthy donors. We found that the MagSweeper effectively isolated CTCs with a capture efficiency that matched the CellSearch platform. However, unlike CellSearch, the MagSweeper facilitates isolation of individual live CTCs without contaminating leukocytes. Importantly, mRNA-Seq analysis showed that the MagSweeper isolation process did not have a discernible impact on the transcriptional profile of single LNCaPs isolated from spiked human blood, suggesting that any perturbations caused by the MagSweeper process on the transcriptional signature of isolated cells are modest. Although the RNA from patient CTCs showed signs of significant degradation, consistent with reports of short half-lives and apoptosis amongst CTCs, transcriptional signatures of prostate tissue and of cancer were readily detectable with single CTC mRNA-Seq. These results demonstrate that the MagSweeper provides access to intact CTCs and that these CTCs can potentially supply clinically relevant information.

  4. mRNA-Seq of single prostate cancer circulating tumor cells reveals recapitulation of gene expression and pathways found in prostate cancer.

    Science.gov (United States)

    Cann, Gordon M; Gulzar, Zulfiqar G; Cooper, Samantha; Li, Robin; Luo, Shujun; Tat, Mai; Stuart, Sarah; Schroth, Gary; Srinivas, Sandhya; Ronaghi, Mostafa; Brooks, James D; Talasaz, Amirali H

    2012-01-01

    Circulating tumor cells (CTC) mediate metastatic spread of many solid tumors and enumeration of CTCs is currently used as a prognostic indicator of survival in metastatic prostate cancer patients. Some evidence suggests that it is possible to derive additional information about tumors from expression analysis of CTCs, but the technical difficulty of isolating and analyzing individual CTCs has limited progress in this area. To assess the ability of a new generation of MagSweeper to isolate intact CTCs for downstream analysis, we performed mRNA-Seq on single CTCs isolated from the blood of patients with metastatic prostate cancer and on single prostate cancer cell line LNCaP cells spiked into the blood of healthy donors. We found that the MagSweeper effectively isolated CTCs with a capture efficiency that matched the CellSearch platform. However, unlike CellSearch, the MagSweeper facilitates isolation of individual live CTCs without contaminating leukocytes. Importantly, mRNA-Seq analysis showed that the MagSweeper isolation process did not have a discernible impact on the transcriptional profile of single LNCaPs isolated from spiked human blood, suggesting that any perturbations caused by the MagSweeper process on the transcriptional signature of isolated cells are modest. Although the RNA from patient CTCs showed signs of significant degradation, consistent with reports of short half-lives and apoptosis amongst CTCs, transcriptional signatures of prostate tissue and of cancer were readily detectable with single CTC mRNA-Seq. These results demonstrate that the MagSweeper provides access to intact CTCs and that these CTCs can potentially supply clinically relevant information.

  5. Dioxin exposure of human CD34+ hemopoietic cells induces gene expression modulation that recapitulates its in vivo clinical and biological effects

    International Nuclear Information System (INIS)

    Fracchiolla, Nicola Stefano; Todoerti, Katia; Bertazzi, Pier Alberto; Servida, Federica; Corradini, Paolo; Carniti, Cristiana; Colombi, Antonio; Cecilia Pesatori, Angela; Neri, Antonino; Deliliers, Giorgio Lambertenghi

    2011-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has a large number of biological effects, including skin, cardiovascular, neurologic diseases, diabetes, infertility, cancers and immunotoxicity. We analysed the in vitro TCDD effects on human CD34 + cells and tested the gene expression modulation by means of microarray analyses before and after TCDD exposure. We identified 257 differentially modulated probe sets, identifying 221 well characterized genes. A large part of these resulted associated to cell adhesion and/or angiogenesis and to transcription regulation. Synaptic transmission and visual perception functions, with the particular involvement of the GABAergic pathway were also significantly modulated. Numerous transcripts involved in cell cycle or cell proliferation, immune response, signal transduction, ion channel activity or calcium ion binding, tissue development and differentiation, female or male fertility or in several metabolic pathways were also affected after dioxin exposure. The transcriptional profile induced by TCDD treatment on human CD34 + cells strikingly reproduces the clinical and biological effects observed in individuals exposed to dioxin and in biological experimental systems. Our data support a role of dioxin in the neoplastic transformation of hemopoietic stem cells and in immune modulation processes after in vivo exposure, as indicated by the epidemiologic data in dioxin accidentally exposed populations, providing a molecular basis for it. In addition, TCDD alters genes associated to glucidic and lipidic metabolisms, to GABAergic transmission or involved in male and female fertility, thus providing a possible explanation of the diabetogenic, dyslipidemic, neurologic and fertility effects induced by TCDD in vivo exposure.

  6. Influence of industrial exhalations on the fertility of ground and on the yields of agricultural plants: a recapitulation of the attained results

    Energy Technology Data Exchange (ETDEWEB)

    Kozel, J; Maly, V

    1964-01-01

    Deposition of dust and ambient concentrations of SO2 were measured around industrial areas in Czechoslovakia in 1961 and 1962. The amount of surface-adhered material and the SO3 content of plant ashes was also measured. Chemical analyses of soils in the areas were also carried out. Dimunition of agricultural productivity was documented. Maize and beans were the crops most affected by air pollution, followed by sugar beets, cereals, (wheat, oats and barley) in order of decreasing effect. 24 references, 4 figures, 5 tables.

  7. A preclinical orthotopic model for glioblastoma recapitulates key features of human tumors and demonstrates sensitivity to a combination of MEK and PI3K pathway inhibitors.

    Science.gov (United States)

    El Meskini, Rajaa; Iacovelli, Anthony J; Kulaga, Alan; Gumprecht, Michelle; Martin, Philip L; Baran, Maureen; Householder, Deborah B; Van Dyke, Terry; Weaver Ohler, Zoë

    2015-01-01

    Current therapies for glioblastoma multiforme (GBM), the highest grade malignant brain tumor, are mostly ineffective, and better preclinical model systems are needed to increase the successful translation of drug discovery efforts into the clinic. Previous work describes a genetically engineered mouse (GEM) model that contains perturbations in the most frequently dysregulated networks in GBM (driven by RB, KRAS and/or PI3K signaling and PTEN) that induce development of Grade IV astrocytoma with properties of the human disease. Here, we developed and characterized an orthotopic mouse model derived from the GEM that retains the features of the GEM model in an immunocompetent background; however, this model is also tractable and efficient for preclinical evaluation of candidate therapeutic regimens. Orthotopic brain tumors are highly proliferative, invasive and vascular, and express histology markers characteristic of human GBM. Primary tumor cells were examined for sensitivity to chemotherapeutics and targeted drugs. PI3K and MAPK pathway inhibitors, when used as single agents, inhibited cell proliferation but did not result in significant apoptosis. However, in combination, these inhibitors resulted in a substantial increase in cell death. Moreover, these findings translated into the in vivo orthotopic model: PI3K or MAPK inhibitor treatment regimens resulted in incomplete pathway suppression and feedback loops, whereas dual treatment delayed tumor growth through increased apoptosis and decreased tumor cell proliferation. Analysis of downstream pathway components revealed a cooperative effect on target downregulation. These concordant results, together with the morphologic similarities to the human GBM disease characteristics of the model, validate it as a new platform for the evaluation of GBM treatment. © 2015. Published by The Company of Biologists Ltd.

  8. A preclinical orthotopic model for glioblastoma recapitulates key features of human tumors and demonstrates sensitivity to a combination of MEK and PI3K pathway inhibitors

    Directory of Open Access Journals (Sweden)

    Rajaa El Meskini

    2015-01-01

    Full Text Available Current therapies for glioblastoma multiforme (GBM, the highest grade malignant brain tumor, are mostly ineffective, and better preclinical model systems are needed to increase the successful translation of drug discovery efforts into the clinic. Previous work describes a genetically engineered mouse (GEM model that contains perturbations in the most frequently dysregulated networks in GBM (driven by RB, KRAS and/or PI3K signaling and PTEN that induce development of Grade IV astrocytoma with properties of the human disease. Here, we developed and characterized an orthotopic mouse model derived from the GEM that retains the features of the GEM model in an immunocompetent background; however, this model is also tractable and efficient for preclinical evaluation of candidate therapeutic regimens. Orthotopic brain tumors are highly proliferative, invasive and vascular, and express histology markers characteristic of human GBM. Primary tumor cells were examined for sensitivity to chemotherapeutics and targeted drugs. PI3K and MAPK pathway inhibitors, when used as single agents, inhibited cell proliferation but did not result in significant apoptosis. However, in combination, these inhibitors resulted in a substantial increase in cell death. Moreover, these findings translated into the in vivo orthotopic model: PI3K or MAPK inhibitor treatment regimens resulted in incomplete pathway suppression and feedback loops, whereas dual treatment delayed tumor growth through increased apoptosis and decreased tumor cell proliferation. Analysis of downstream pathway components revealed a cooperative effect on target downregulation. These concordant results, together with the morphologic similarities to the human GBM disease characteristics of the model, validate it as a new platform for the evaluation of GBM treatment.

  9. Humanized mice recapitulate key features of HIV-1 infection: a novel concept using long-acting anti-retroviral drugs for treating HIV-1.

    Directory of Open Access Journals (Sweden)

    Marc Nischang

    Full Text Available BACKGROUND: Humanized mice generate a lymphoid system of human origin subsequent to transplantation of human CD34+ cells and thus are highly susceptible to HIV infection. Here we examined the efficacy of antiretroviral treatment (ART when added to food pellets, and of long-acting (LA antiretroviral compounds, either as monotherapy or in combination. These studies shall be inspiring for establishing a gold standard of ART, which is easy to administer and well supported by the mice, and for subsequent studies such as latency. Furthermore, they should disclose whether viral breakthrough and emergence of resistance occurs similar as in HIV-infected patients when ART is insufficient. METHODS/PRINCIPAL FINDINGS: NOD/shi-scid/γ(cnull (NOG mice were used in all experimentations. We first performed pharmacokinetic studies of the drugs used, either added to food pellets (AZT, TDF, 3TC, RTV or in a LA formulation that permitted once weekly subcutaneous administration (TMC278: non-nucleoside reverse transcriptase inhibitor, TMC181: protease inhibitor. A combination of 3TC, TDF and TMC278-LA or 3TC, TDF, TMC278-LA and TMC181-LA suppressed the viral load to undetectable levels in 15/19 (79% and 14/14 (100% mice, respectively. In successfully treated mice, subsequent monotherapy with TMC278-LA resulted in viral breakthrough; in contrast, the two LA compounds together prevented viral breakthrough. Resistance mutations matched the mutations most commonly observed in HIV patients failing therapy. Importantly, viral rebound after interruption of ART, presence of HIV DNA in successfully treated mice and in vitro reactivation of early HIV transcripts point to an existing latent HIV reservoir. CONCLUSIONS/SIGNIFICANCE: This report is a unique description of multiple aspects of HIV infection in humanized mice that comprised efficacy testing of various treatment regimens, including LA compounds, resistance mutation analysis as well as viral rebound after treatment interruption. Humanized mice will be highly valuable for exploring the antiviral potency of new compounds or compounds targeting the latent HIV reservoir.

  10. Newly-derived neuroblastoma cell lines propagated in serum-free media recapitulate the genotype and phenotype of primary neuroblastoma tumours.

    Science.gov (United States)

    Bate-Eya, Laurel T; Ebus, Marli E; Koster, Jan; den Hartog, Ilona J M; Zwijnenburg, Danny A; Schild, Linda; van der Ploeg, Ida; Dolman, M Emmy M; Caron, Huib N; Versteeg, Rogier; Molenaar, Jan J

    2014-02-01

    Recently protocols have been devised for the culturing of cell lines from fresh tumours under serum-free conditions in defined neural stem cell medium. These cells, frequently called tumour initiating cells (TICs) closely retained characteristics of the tumours of origin. We report the isolation of eight newly-derived neuroblastoma TICs from six primary neuroblastoma tumours and two bone marrow metastases. The primary tumours from which these TICs were generated have previously been fully typed by whole genome sequencing (WGS). Array comparative genomic hybridisation (aCGH) analysis showed that TIC lines retained essential characteristics of the primary tumours and exhibited typical neuroblastoma chromosomal aberrations such as MYCN amplification, gain of chromosome 17q and deletion of 1p36. Protein analysis showed expression for neuroblastoma markers MYCN, NCAM, CHGA, DBH and TH while haematopoietic markers CD19 and CD11b were absent. We analysed the growth characteristics and confirmed tumour-forming potential using sphere-forming assays, subcutaneous and orthotopic injection of these cells into immune-compromised mice. Affymetrix mRNA expression profiling of TIC line xenografts showed an expression pattern more closely mimicking primary tumours compared to xenografts from classical cell lines. This establishes that these neuroblastoma TICs cultured under serum-free conditions are relevant and useful neuroblastoma tumour models. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Interspecific hybridization, polyploidization, and backcross of Brassica oleracea var. alboglabra with B. rapa var. purpurea morphologically recapitulate the evolution of Brassica vegetables.

    Science.gov (United States)

    Zhang, Xiaohui; Liu, Tongjin; Li, Xixiang; Duan, Mengmeng; Wang, Jinglei; Qiu, Yang; Wang, Haiping; Song, Jiangping; Shen, Di

    2016-01-04

    Brassica oleracea and B. rapa are two important vegetable crops. Both are composed of dozens of subspecies encompassing hundreds of varieties and cultivars. Synthetic B. napus with these two plants has been used extensively as a research model for the investigation of allopolyploid evolution. However, the mechanism underlying the explosive evolution of hundreds of varieties of B. oleracea and B. rapa within a short period is poorly understood. In the present study, interspecific hybridization between B. oleracea var. alboglabra and B. rapa var. purpurea was performed. The backcross progeny displayed extensive morphological variation, including some individuals that phenocopied subspecies other than their progenitors. Numerous interesting novel phenotypes and mutants were identified among the backcross progeny. The chromosomal recombination between the A and C genomes and the chromosomal asymmetric segregation were revealed using Simple Sequence Repeats (SSR) markers. These findings provide direct evidence in support of the hypothesis that interspecific hybridization and backcrossing have played roles in the evolution of the vast variety of vegetables among these species and suggest that combination of interspecific hybridization and backcrossing may facilitate the development of new mutants and novel phenotypes for both basic research and the breeding of new vegetable crops.

  12. A Mouse Model that Recapitulates Cardinal Features of the 15q13.3 Microdeletion Syndrome Including Schizophrenia- and Epilepsy-Related Alterations

    DEFF Research Database (Denmark)

    Fejgin, Kim; Nielsen, Jacob; Birknow, Michelle R.

    2014-01-01

    to develop myoclonic and absence-like seizures but decreased propensity for clonic and tonic seizures. Furthermore, they had impaired long-term spatial reference memory and a decreased theta frequency in hippocampus and prefrontal cortex. Electroencephalogram characterization revealed auditory processing......Background: Genome-wide scans have uncovered rare copy number variants conferring high risk of psychiatric disorders. The 15q13.3 microdeletion is associated with a considerably increased risk of idiopathic generalized epilepsy, intellectual disability, and schizophrenia. Methods: A 15q13.......3 microdeletion mouse model (Df[h15q13]/) was generated by hemizygous deletion of the orthologous region and characterized with focus on schizophrenia- and epilepsy-relevant parameters. Results: Df(h15q13)/ mice showed marked changes in neuronal excitability in acute seizure assays, with increased propensity...

  13. Controlled Release Strategies for Bone, Cartilage, and Osteochondral Engineering—Part I: Recapitulation of Native Tissue Healing and Variables for the Design of Delivery Systems

    Science.gov (United States)

    Santo, Vítor E.; Mano, João F.; Reis, Rui L.

    2013-01-01

    The potential of growth factors to stimulate tissue healing through the enhancement of cell proliferation, migration, and differentiation is undeniable. However, critical parameters on the design of adequate carriers, such as uncontrolled spatiotemporal presence of bioactive factors, inadequate release profiles, and supraphysiological dosages of growth factors, have impaired the translation of these systems onto clinical practice. This review describes the healing cascades for bone, cartilage, and osteochondral interface, highlighting the role of specific growth factors for triggering the reactions leading to tissue regeneration. Critical criteria on the design of carriers for controlled release of bioactive factors are also reported, focusing on the need to provide a spatiotemporal control over the delivery and presentation of these molecules. PMID:23268651

  14. Zebrafish mutants in the von Hippel-Lindau tumor suppressor display a hypoxic response and recapitulate key aspects of Chuvash polycythemia

    NARCIS (Netherlands)

    van Rooijen, E.; Voest, E.E.; Logister, I.; Korving, J.; Schwerte, T.; Schulte-Merker, S.; Giles, R.H.; van Eeden, F.J.

    2009-01-01

    We have generated 2 zebrafish lines carrying inactivating germline mutations in the von Hippel-Lindau (VHL) tumor suppressor gene ortholog vhl. Mutant embryos display a general systemic hypoxic response, including the up-regulation of hypoxia-induced genes by 1 day after fertilization and a severe

  15. Newly-derived neuroblastoma cell lines propagated in serum-free media recapitulate the genotype and phenotype of primary neuroblastoma tumours

    NARCIS (Netherlands)

    Bate-Eya, Laurel T.; Ebus, Marli E.; Koster, Jan; den Hartog, Ilona J. M.; Zwijnenburg, Danny A.; Schild, Linda; van der Ploeg, Ida; Dolman, M. Emmy M.; Caron, Huib N.; Versteeg, Rogier; Molenaar, Jan J.

    2014-01-01

    Recently protocols have been devised for the culturing of cell lines from fresh tumours under serum-free conditions in defined neural stem cell medium. These cells, frequently called tumour initiating cells (TICs) closely retained characteristics of the tumours of origin. We report the isolation of

  16. Low dose rectal inoculation of rhesus macaques by SIV SME660 or SIV MAC251 recapitulates human mucosal infection by HIV-1

    Energy Technology Data Exchange (ETDEWEB)

    Koraber, Bette [Los Alamos National Laboratory; Perelson, Alan [Los Alamos National Laboratory; Hraber, Peter [Los Alamos National Laboratory; Giorgi, E [Los Alamos National Laboratory; Bhattacharya, T [Los Alamos National Laboratory

    2009-01-01

    Recently, we developed a novel approach to the identification of transmitted or early founder HIV -1 genomes in acutely infected humans based on single genome amplification and sequencing. Here we tested this approach in 18 acutely infected Indian rhesus macaques to determine the molecular features of SIV transmission. Animals were inoculated intrarectally (IR) or intravenously (IV) with stocks of SIVmac251 or SIVsmE660 that exhibited sequence diversity typical of early-chronic HIV -1 infection. 987 full-length SIV env sequences (median of 48 per animal) were determined from plasma virion RNA one to five weeks after infection. IR inoculation was followed by productive infection by one or few viruses (median 1; range 1-5) that diversified randomly with near star-like phylogeny and a Poisson distribution of mutations. Consensus viral sequences from ramp-up and peak viremia were identical to viruses found in the inocula or differed from them by only one or few nuc1eotides, providing direct evidence that early plasma viral sequences coalesce to transmitted/founder virus( es). IV infection was approximately 10,000-fold more efficient than IR infection, and viruses transmitted by either route represented the full genetic spectra of the inocula. These findings identify key similarities in mucosal transmission and early diversification between SIV and HIV -1.

  17. Serum miR-451a Levels Are Significantly Elevated in Women With Endometriosis and Recapitulated in Baboons ( Papio anubis) With Experimentally-Induced Disease.

    Science.gov (United States)

    Nothnick, Warren B; Falcone, Tommaso; Joshi, Niraj; Fazleabas, Asgerally T; Graham, Amanda

    2017-08-01

    We have previously demonstrated that human microRNA-451a (miR-451a) endometriotic lesion expression is significantly higher compared to that of the corresponding eutopic endometrium. The objective of the current study was to examine the relationship between lesion and serum content of miR-451a and to determine the utility of serum miR-451a in distinguishing between women with and without visible signs of endometriosis. Eighty-one participants were enrolled in this study, 41 with confirmed endometriosis and 40 without visible signs of endometriosis at laparoscopy (n = 20) or symptoms of endometriosis (pain, infertility n = 20). Experimental endometriosis was also induced in 8 baboons. Blood, endometriotic lesions, and eutopic endometrial samples were collected from women undergoing laparoscopy for surgical removal of endometriosis. Blood was also collected from control participants with no signs and symptoms associated with the disease as well as from baboons prior to, and then 1, 3, 6, 9, and 15 months postinduction of endometriosis. MicroRNA-451a was assessed by quantitative real-time polymerase chain reaction in all samples. In humans, serum miR-451a levels positively correlated with endometriotic lesion miR-451a content, and sera levels were significantly higher in these participants compared to controls. The area under the curve (AUC) for miR-451a was 0.8599. In baboons, serum miR-451a reached statistically significant peak levels at 6 months postinduction of endometriosis. We conclude from this study that sera miR-451a levels positively correlated with endometriotic lesion content and are significantly greater compared to sera levels in women without visible signs or symptoms of endometriosis. MicroRNA-451a may serve as a serum diagnostic marker for endometriosis.

  18. Recapitulation of the Research Leading to the Treatise on "Physical Hydrodynamics with Applications to Dynamical Meteorology" as recorded by V. Bjerknes, 1933

    OpenAIRE

    Berger, Wolfgang H

    2007-01-01

    Vilhelm Frimann Koren Bjerknes, Norwegian physicist (1862-1951), was a central figure in the pioneering stage of modern meteorology and oceanography. His meteorological theories (especially with regard to cyclogenesis along the polar front) helped establish the basis for weather forecasting in temperate and high latitudes. His mathematical treatment of water motions in the sea helped establish the foundations for dynamic oceanography. Bjerknes was the leading figure of the "Bergen Sc...

  19. Journal of Genetics | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics. L. S. Shashidhara. Articles written in Journal of Genetics. Volume 79 Issue 2 August 2000 pp 61-70. Negative regulation of Ultrabithorax expression by engrailed is required for proper specification of wing development in Drosophila melanogaster · B. Starling Emerald L. S. Shashidhara.

  20. A de novo 10p11.23-p12.1 deletion recapitulates the phenotype observed in WAC mutations and strengthens the role of WAC in intellectual disability and behavior disorders.

    Science.gov (United States)

    Abdelhedi, Fatma; El Khattabi, Laila; Essid, Nouha; Viot, Geraldine; Letessier, Dominique; Lebbar, Aziza; Dupont, Jean-Michel

    2016-07-01

    Chromosomal microarray analysis has become a powerful diagnostic tool in the investigation of patients with intellectual disability leading to the discovery of dosage sensitive genes implicated in the manifestation of various genomic disorders. Interstitial deletions of the short arm of chromosome 10 represent rare genetic abnormalities, especially those encompassing the chromosomal region 10p11-p12. To date, only 10 postnatal cases with microdeletion of this region have been described, and all patients shared a common phenotype, including intellectual disability, abnormal behavior, distinct dysmorphic features, visual impairment, and cardiac malformations. WAC was suggested to be the main candidate gene for intellectual disability associated with 10 p11-p12 deletion syndrome. Here, we describe a new case of de novo 10p11.23-p12.1 microdeletion in a patient with intellectual disability, abnormal behavior, and distinct dysmorphic features. Our observation allows us to redefine the smallest region of overlap among patients reported so far, with a size of 80 Kb and which contains only the WAC gene. These findings strengthen the hypothesis that haploinsufficency of WAC gene might be likely responsible for intellectual disability and behavior disorders. Our data also led us to propose a clinical pathway for patients with this recognizable genetic syndrome depending on the facial dysmorphisms. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  1. Fibulin-4 E57K Knock-in Mice Recapitulate Cutaneous, Vascular and Skeletal Defects of Recessive Cutis Laxa 1B with both Elastic Fiber and Collagen Fibril Abnormalities.

    Science.gov (United States)

    Igoucheva, Olga; Alexeev, Vitali; Halabi, Carmen M; Adams, Sheila M; Stoilov, Ivan; Sasaki, Takako; Arita, Machiko; Donahue, Adele; Mecham, Robert P; Birk, David E; Chu, Mon-Li

    2015-08-28

    Fibulin-4 is an extracellular matrix protein essential for elastic fiber formation. Frameshift and missense mutations in the fibulin-4 gene (EFEMP2/FBLN4) cause autosomal recessive cutis laxa (ARCL) 1B, characterized by loose skin, aortic aneurysm, arterial tortuosity, lung emphysema, and skeletal abnormalities. Homozygous missense mutations in FBLN4 are a prevalent cause of ARCL 1B. Here we generated a knock-in mouse strain bearing a recurrent fibulin-4 E57K homozygous missense mutation. The mutant mice survived into adulthood and displayed abnormalities in multiple organ systems, including loose skin, bent forelimb, aortic aneurysm, tortuous artery, and pulmonary emphysema. Biochemical studies of dermal fibroblasts showed that fibulin-4 E57K mutant protein was produced but was prone to dimer formation and inefficiently secreted, thereby triggering an endoplasmic reticulum stress response. Immunohistochemistry detected a low level of fibulin-4 E57K protein in the knock-in skin along with altered expression of selected elastic fiber components. Processing of a precursor to mature lysyl oxidase, an enzyme involved in cross-linking of elastin and collagen, was compromised. The knock-in skin had a reduced level of desmosine, an elastin-specific cross-link compound, and ultrastructurally abnormal elastic fibers. Surprisingly, structurally aberrant collagen fibrils and altered organization into fibers were characteristics of the knock-in dermis and forelimb tendons. Type I collagen extracted from the knock-in skin had decreased amounts of covalent intermolecular cross-links, which could contribute to the collagen fibril abnormalities. Our studies provide the first evidence that fibulin-4 plays a role in regulating collagen fibril assembly and offer a preclinical platform for developing treatments for ARCL 1B. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Ubx regulates differential enlargement and diversification of insect hind legs.

    Directory of Open Access Journals (Sweden)

    Najmus Mahfooz

    2007-09-01

    Full Text Available Differential enlargement of hind (T3 legs represents one of the hallmarks of insect evolution. However, the actual mechanism(s responsible are yet to be determined. To address this issue, we have now studied the molecular basis of T3 leg enlargement in Oncopeltus fasciatus (milkweed bug and Acheta domesticus (house cricket. In Oncopeltus, the T3 tibia displays a moderate increase in size, whereas in Acheta, the T3 femur, tibia, and tarsus are all greatly enlarged. Here, we show that the hox gene Ultrabithorax (Ubx is expressed in the enlarged segments of hind legs. Furthermore, we demonstrate that depletion of Ubx during embryogenesis has a primary effect in T3 legs and causes shortening of leg segments that are enlarged in a wild type. This result shows that Ubx is regulating the differential growth and enlargement of T3 legs in both Oncopeltus and Acheta. The emerging view suggests that Ubx was co-opted for a novel role in regulating leg growth and that the transcriptional modification of its expression may be a universal mechanism for the evolutionary diversification of insect hind legs.

  3. Genetic and Environmental Control of Neurodevelopmental Robustness in Drosophila.

    Directory of Open Access Journals (Sweden)

    David J Mellert

    Full Text Available Interindividual differences in neuronal wiring may contribute to behavioral individuality and affect susceptibility to neurological disorders. To investigate the causes and potential consequences of wiring variation in Drosophila melanogaster, we focused on a hemilineage of ventral nerve cord interneurons that exhibits morphological variability. We find that late-born subclasses of the 12A hemilineage are highly sensitive to genetic and environmental variation. Neurons in the second thoracic segment are particularly variable with regard to two developmental decisions, whereas its segmental homologs are more robust. This variability "hotspot" depends on Ultrabithorax expression in the 12A neurons, indicating variability is cell-intrinsic and under genetic control. 12A development is more variable and sensitive to temperature in long-established laboratory strains than in strains recently derived from the wild. Strains with a high frequency of one of the 12A variants also showed a high frequency of animals with delayed spontaneous flight initiation, whereas other wing-related behaviors did not show such a correlation and were thus not overtly affected by 12A variation. These results show that neurodevelopmental robustness is variable and under genetic control in Drosophila and suggest that the fly may serve as a model for identifying conserved gene pathways that stabilize wiring in stressful developmental environments. Moreover, some neuronal lineages are variation hotspots and thus may be more amenable to evolutionary change.

  4. Org-1-dependent lineage reprogramming generates the ventral longitudinal musculature of the Drosophila heart.

    Science.gov (United States)

    Schaub, Christoph; März, Johannes; Reim, Ingolf; Frasch, Manfred

    2015-02-16

    Only few examples of transdifferentiation, which denotes the conversion of one differentiated cell type to another, are known to occur during normal development, and more often, it is associated with regeneration processes. With respect to muscles, dedifferentiation/redifferentiation processes have been documented during post-traumatic muscle regeneration in blastema of newts as well as during myocardial regeneration. As shown herein, the ventral longitudinal muscles of the adult Drosophila heart arise from specific larval alary muscles in a process that represents the first known example of syncytial muscle transdifferentiation via dedifferentiation into mononucleate myoblasts during normal development. We demonstrate that this unique process depends on the reinitiation of a transcriptional program previously employed for embryonic alary muscle development, in which the factors Org-1 (Drosophila Tbx1) and Tailup (Drosophila Islet1) are key components. During metamorphosis, the action of these factors is combined with cell-autonomous inputs from the ecdysone steroid and the Hox gene Ultrabithorax, which provide temporal and spatial specificity to the transdifferentiation events. Following muscle dedifferentiation, inductive cues, particularly from the remodeling heart tube, are required for the redifferentiation of myoblasts into ventral longitudinal muscles. Our results provide new insights into mechanisms of lineage commitment and cell-fate plasticity during development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Fine Mapping of a Degenerated Abdominal Legs Mutant (Edl in Silkworm, Bombyx mori.

    Directory of Open Access Journals (Sweden)

    Honglei Wang

    Full Text Available In insects, abdominal appendages, also called prolegs, vary due to adaptive evolution. Mutations on prolegs within species provide insights to better understand the mechanisms underlying appendage development and diversity. In silkworm Bombyx mori, extra-crescents and degenerated abdominal legs (Edl mutant, belonging to the E pseudoallele group, is a spontaneous mutation that adds crescents and degenerates prolegs on the third abdominal segment (A3. This mutation may be a homeotic transformation of A3 to A2. In this study, the Edl locus was mapped within approximately a 211 Kb region that is 10 Kb upstream of Bmabdominal-A (Bmabd-A. RT-quantitative PCR (RT-qPCR and Western blot analysis of Bmabd-A expression showed a slight but significant decrease, while the expression of BmUltrabithorax (BmUbx was up-regulated in the Edl mutant compared to wildtype (Dazao. Moreover, we also found that BmDistal-less (BmDll, which regulated the development of distal proleg structures, was missing at the tips of the A3 prolegs in the Edl mutant compared to BmDll expression in normally developed prolegs in both the wildtype and mutant. Collectively, we identified approximately a 211 Kb region in the Edl locus that regulates BmUbx and Bmabd-A expression and found that changes in BmUbx and Bmabd-A expression may lead to the loss of distal proleg structures in B. mori.

  6. Drosophila atonal fully rescues the phenotype of Math1 null mice: new functions evolve in new cellular contexts

    Science.gov (United States)

    Wang, Vincent Y.; Hassan, Bassem A.; Bellen, Hugo J.; Zoghbi, Huda Y.

    2002-01-01

    Many genes share sequence similarity between species, but their properties often change significantly during evolution. For example, the Drosophila genes engrailed and orthodenticle and the onychophoran gene Ultrabithorax only partially substitute for their mouse or Drosophila homologs. We have been analyzing the relationship between atonal (ato) in the fruit fly and its mouse homolog, Math1. In flies, ato acts as a proneural gene that governs the development of chordotonal organs (CHOs), which serve as stretch receptors in the body wall and joints and as auditory organs in the antennae. In the fly CNS, ato is important not for specification but for axonal arborization. Math1, in contrast, is required for the specification of cells in both the CNS and the PNS. Furthermore, Math1 serves a role in the development of secretory lineage cells in the gut, a function that does not parallel any known to be served by ato. We wondered whether ato and Math1 might be more functionally homologous than they appear, so we expressed Math1 in ato mutant flies and ato in Math1 null mice. To our surprise, the two proteins are functionally interchangeable.

  7. Selector genes display tumor cooperation and inhibition in Drosophila epithelium in a developmental context-dependent manner

    Directory of Open Access Journals (Sweden)

    Ram Prakash Gupta

    2017-11-01

    Full Text Available During animal development, selector genes determine identities of body segments and those of individual organs. Selector genes are also misexpressed in cancers, although their contributions to tumor progression per se remain poorly understood. Using a model of cooperative tumorigenesis, we show that gain of selector genes results in tumor cooperation, but in only select developmental domains of the wing, haltere and eye-antennal imaginal discs of Drosophila larva. Thus, the field selector, Eyeless (Ey, and the segment selector, Ultrabithorax (Ubx, readily cooperate to bring about neoplastic transformation of cells displaying somatic loss of the tumor suppressor, Lgl, but in only those developmental domains that express the homeo-box protein, Homothorax (Hth, and/or the Zinc-finger protein, Teashirt (Tsh. In non-Hth/Tsh-expressing domains of these imaginal discs, however, gain of Ey in lgl− somatic clones induces neoplastic transformation in the distal wing disc and haltere, but not in the eye imaginal disc. Likewise, gain of Ubx in lgl− somatic clones induces transformation in the eye imaginal disc but not in its endogenous domain, namely, the haltere imaginal disc. Our results reveal that selector genes could behave as tumor drivers or inhibitors depending on the tissue contexts of their gains.

  8. Small ubiquitin-like modifier (SUMO) conjugation impedes transcriptional silencing by the polycomb group repressor Sex Comb on Midleg.

    Science.gov (United States)

    Smith, Matthew; Mallin, Daniel R; Simon, Jeffrey A; Courey, Albert J

    2011-04-01

    The Drosophila protein Sex Comb on Midleg (Scm) is a member of the Polycomb group (PcG), a set of transcriptional repressors that maintain silencing of homeotic genes during development. Recent findings have identified PcG proteins both as targets for modification by the small ubiquitin-like modifier (SUMO) protein and as catalytic components of the SUMO conjugation pathway. We have found that the SUMO-conjugating enzyme Ubc9 binds to Scm and that this interaction, which requires the Scm C-terminal sterile α motif (SAM) domain, is crucial for the efficient sumoylation of Scm. Scm is associated with the major Polycomb response element (PRE) of the homeotic gene Ultrabithorax (Ubx), and efficient PRE recruitment requires an intact Scm SAM domain. Global reduction of sumoylation augments binding of Scm to the PRE. This is likely to be a direct effect of Scm sumoylation because mutations in the SUMO acceptor sites in Scm enhance its recruitment to the PRE, whereas translational fusion of SUMO to the Scm N terminus interferes with this recruitment. In the metathorax, Ubx expression promotes haltere formation and suppresses wing development. When SUMO levels are reduced, we observe decreased expression of Ubx and partial haltere-to-wing transformation phenotypes. These observations suggest that SUMO negatively regulates Scm function by impeding its recruitment to the Ubx major PRE.

  9. Small Ubiquitin-like Modifier (SUMO) Conjugation Impedes Transcriptional Silencing by the Polycomb Group Repressor Sex Comb on Midleg*

    Science.gov (United States)

    Smith, Matthew; Mallin, Daniel R.; Simon, Jeffrey A.; Courey, Albert J.

    2011-01-01

    The Drosophila protein Sex Comb on Midleg (Scm) is a member of the Polycomb group (PcG), a set of transcriptional repressors that maintain silencing of homeotic genes during development. Recent findings have identified PcG proteins both as targets for modification by the small ubiquitin-like modifier (SUMO) protein and as catalytic components of the SUMO conjugation pathway. We have found that the SUMO-conjugating enzyme Ubc9 binds to Scm and that this interaction, which requires the Scm C-terminal sterile α motif (SAM) domain, is crucial for the efficient sumoylation of Scm. Scm is associated with the major Polycomb response element (PRE) of the homeotic gene Ultrabithorax (Ubx), and efficient PRE recruitment requires an intact Scm SAM domain. Global reduction of sumoylation augments binding of Scm to the PRE. This is likely to be a direct effect of Scm sumoylation because mutations in the SUMO acceptor sites in Scm enhance its recruitment to the PRE, whereas translational fusion of SUMO to the Scm N terminus interferes with this recruitment. In the metathorax, Ubx expression promotes haltere formation and suppresses wing development. When SUMO levels are reduced, we observe decreased expression of Ubx and partial haltere-to-wing transformation phenotypes. These observations suggest that SUMO negatively regulates Scm function by impeding its recruitment to the Ubx major PRE. PMID:21278366

  10. Melt Electrospinning Writing of Poly-Hydroxymethylglycolide-co-ε-Caprolactone-Based Scaffolds for Cardiac Tissue Engineering

    NARCIS (Netherlands)

    Castilho, Miguel; Feyen, Dries; Flandes-Iparraguirre, María; Hochleitner, Gernot; Groll, Jürgen; Doevendans, Pieter A.F.; Vermonden, Tina; Ito, Keita; Sluijter, Joost P G; Malda, Jos

    2017-01-01

    Current limitations in cardiac tissue engineering revolve around the inability to fully recapitulate the structural organization and mechanical environment of native cardiac tissue. This study aims at developing organized ultrafine fiber scaffolds with improved biocompatibility and architecture in

  11. Melt Electrospinning Writing of Poly-Hydroxymethylglycolide-co-ε-Caprolactone-Based Scaffolds for Cardiac Tissue Engineering

    NARCIS (Netherlands)

    Castilho, Miguel; Feyen, Dries; Flandes-Iparraguirre, María; Hochleitner, Gernot; Groll, Jürgen; Doevendans, Pieter A.F.; Vermonden, Tina; Ito, Keita; Sluijter, Joost P.G.; Malda, Jos

    Current limitations in cardiac tissue engineering revolve around the inability to fully recapitulate the structural organization and mechanical environment of native cardiac tissue. This study aims at developing organized ultrafine fiber scaffolds with improved biocompatibility and architecture in

  12. Melt electrospinning writing of poly-Hydroxymethylglycolide-co-ε-Caprolactone-based scaffolds for cardiac tissue engineering

    NARCIS (Netherlands)

    Castilho, M.; Feyen, D.; Flandes-Iparraguirre, M.; Hochleitner, G.; Groll, J.; Doevendans, P.A.F.; Vermonden, T.; Ito, K.; Sluijter, J.P.G.; Malda, J.

    2017-01-01

    Current limitations in cardiac tissue engineering revolve around the inability to fully recapitulate the structural organization and mechanical environment of native cardiac tissue. This study aims at developing organized ultrafine fiber scaffolds with improved biocompatibility and architecture in

  13. Ageing and recurrent episodes of neuroinflammation promote progressive experimental autoimmune encephalomyelitis in Biozzi ABH mice

    NARCIS (Netherlands)

    Peferoen, Laura A. N.; Breur, Marjolein; van de Berg, Sarah; Peferoen-Baert, Regina; Boddeke, Erik H. W. G. M.; van der Valk, Paul; Pryce, Gareth; van Noort, Johannes M.; Baker, David; Amor, Sandra

    2016-01-01

    Current therapies for multiple sclerosis (MS) reduce the frequency of relapses by modulating adaptive immune responses but fail to limit the irreversible neurodegeneration driving progressive disability. Experimental autoimmune encephalomyelitis (EAE) in Biozzi ABH mice recapitulates clinical

  14. In Vivo SILAC-Based Proteomics Reveals Phosphoproteome Changes during Mouse Skin Carcinogenesis

    NARCIS (Netherlands)

    Zanivan, S.; Meves, A.; Behrendt, K.; Schoof, E.M.; Neilson, L.J.; Cox, J.; Tang, H.R.; Kalna, G.; Ree, J.H. van; Deursen, J.M.A. van; Trempus, C.S.; Machesky, L.M.; Linding, R.; Wickstrom, S.A.; Fassler, R.; Mann, M.

    2013-01-01

    Cancer progresses through distinct stages, and mouse models recapitulating traits of this progression are frequently used to explore genetic, morphological, and pharmacological aspects of tumor development. To complement genomic investigations of this process, we here quantify phosphoproteomic

  15. 78 FR 8546 - National Center for Advancing Translational Sciences (NCATS) and National Human Genome Research...

    Science.gov (United States)

    2013-02-06

    ... March 8, 2013 for consideration. Guidelines for the preparation of a full CRADA proposal will be... recapitulates the pathologic hallmarks of Gaucher disease,'' Panicker LM, Miller D, Park TS, Patel B, Azevedo JL...

  16. Model organoids provide new research opportunities for ductal pancreatic cancer

    NARCIS (Netherlands)

    Boj, Sylvia F; Hwang, Chang-Il; Baker, Lindsey A; Engle, Dannielle D; Tuveson, David A; Clevers, Hans

    We recently established organoid models from normal and neoplastic murine and human pancreas tissues. These organoids exhibit ductal- and disease stage-specific characteristics and, after orthotopic transplantation, recapitulate the full spectrum of tumor progression. Pancreatic organoid technology

  17. ASSESSMENT OF CHEMICAL EFFECTS ON NEURITE OUTGROWTH, NEURONAL POLARIZATION AND SYNAPTOGENESIS IN RAT CORTICAL NEURONS USING HIGH CONTENT IMAGE ANALYSIS

    Science.gov (United States)

    There is a need for efficient, cost-effective methods for screening and prioritization of potential developmental neurotoxicants. One approach uses in vitro cell culture models that can recapitulate the critical processes of nervous system development. In vitro, primary cultures ...

  18. A Rat Model of Sytemic Chemotherapy for Breast Cancer to Evaluate and Treat Chemobrain

    National Research Council Canada - National Science Library

    Little, Kevin C

    2007-01-01

    ...) that recapitulates the physical symptoms of chemotherapy treatment. We investigated the effects of this regimen on learning and memory as well as on the production and survival of new neurons in the hippocampus (neurogenesis...

  19. Hox gene function and interaction in the milkweed bug Oncopeltus fasciatus (Hemiptera).

    Science.gov (United States)

    Angelini, David R; Liu, Paul Z; Hughes, Cynthia L; Kaufman, Thomas C

    2005-11-15

    Studies in genetic model organisms such as Drosophila have demonstrated that the homeotic complex (Hox) genes impart segmental identity during embryogenesis. Comparative studies in a wide range of other insect taxa have shown that the Hox genes are expressed in largely conserved domains along the anterior-posterior body axis, but whether they are performing the same functions in different insects is an open question. Most of the Hox genes have been studied functionally in only a few holometabolous insects that undergo metamorphosis. Thus, it is unclear how the Hox genes are functioning in the majority of direct-developing insects and other arthropods. To address this question, we used a combination of RNAi and in situ hybridization to reveal the expression, functions, and regulatory interactions of the Hox genes in the milkweed bug Oncopeltus fasciatus. Our results reveal many similarities and some interesting differences compared to Drosophila. We find that the gene Antennapedia is required for the identity of all three thoracic segments, while Ultrabithorax, abdominal-A and Abdominal-B cooperate to pattern the abdomen. The three abdominal genes exhibit posterior prevalence like in Drosophila, but apparently via some post-transcriptional mechanism. The functions of the head genes proboscipedia, Deformed, and Sex combs reduced were shown previously, and here we find that the complex temporal expression of pb in the labium is like that of other insects, but its regulatory relationship with Scr is unique. Overall, our data reveal that the evolution of insect Hox genes has included many small changes within general conservation of expression and function, and that the milkweed bug provides a useful model for understanding the roles of Hox genes in a direct-developing insect.

  20. Org-1 is required for the diversification of circular visceral muscle founder cells and normal midgut morphogenesis.

    Science.gov (United States)

    Schaub, Christoph; Frasch, Manfred

    2013-04-15

    The T-Box family of transcription factors plays fundamental roles in the generation of appropriate spatial and temporal gene expression profiles during cellular differentiation and organogenesis in animals. In this study we report that the Drosophila Tbx1 orthologue optomotor-blind-related-gene-1 (org-1) exerts a pivotal function in the diversification of circular visceral muscle founder cell identities in Drosophila. In embryos mutant for org-1, the specification of the midgut musculature per se is not affected, but the differentiating midgut fails to form the anterior and central midgut constrictions and lacks the gastric caeca. We demonstrate that this phenotype results from the nearly complete loss of the founder cell specific expression domains of several genes known to regulate midgut morphogenesis, including odd-paired (opa), teashirt (tsh), Ultrabithorax (Ubx), decapentaplegic (dpp) and wingless (wg). To address the mechanisms that mediate the regulatory inputs from org-1 towards Ubx, dpp, and wg in these founder cells we genetically dissected known visceral mesoderm specific cis-regulatory-modules (CRMs) of these genes. The analyses revealed that the activities of the dpp and wg CRMs depend on org-1, the CRMs are bound by Org-1 in vivo and their T-Box binding sites are essential for their activation in the visceral muscle founder cells. We conclude that Org-1 acts within a well-defined signaling and transcriptional network of the trunk visceral mesoderm as a crucial founder cell-specific competence factor, in concert with the general visceral mesodermal factor Biniou. As such, it directly regulates several key genes involved in the establishment of morphogenetic centers along the anteroposterior axis of the visceral mesoderm, which subsequently organize the formation of midgut constrictions and gastric caeca and thereby determine the morphology of the midgut. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Hox gene expression leads to differential hind leg development between honeybee castes.

    Science.gov (United States)

    Bomtorin, Ana Durvalina; Barchuk, Angel Roberto; Moda, Livia Maria; Simoes, Zila Luz Paulino

    2012-01-01

    Beyond the physiological and behavioural, differences in appendage morphology between the workers and queens of Apis mellifera are pre-eminent. The hind legs of workers, which are highly specialized pollinators, deserve special attention. The hind tibia of worker has an expanded bristle-free region used for carrying pollen and propolis, the corbicula. In queens this structure is absent. Although the morphological differences are well characterized, the genetic inputs driving the development of this alternative morphology remain unknown. Leg phenotype determination takes place between the fourth and fifth larval instar and herein we show that the morphogenesis is completed at brown-eyed pupa. Using results from the hybridization of whole genome-based oligonucleotide arrays with RNA samples from hind leg imaginal discs of pre-pupal honeybees of both castes we present a list of 200 differentially expressed genes. Notably, there are castes preferentially expressed cuticular protein genes and members of the P450 family. We also provide results of qPCR analyses determining the developmental transcription profiles of eight selected genes, including abdominal-A, distal-less and ultrabithorax (Ubx), whose roles in leg development have been previously demonstrated in other insect models. Ubx expression in workers hind leg is approximately 25 times higher than in queens. Finally, immunohistochemistry assays show that Ubx localization during hind leg development resembles the bristles localization in the tibia/basitarsus of the adult legs in both castes. Our data strongly indicate that the development of the hind legs diphenism characteristic of this corbiculate species is driven by a set of caste-preferentially expressed genes, such as those encoding cuticular protein genes, P450 and Hox proteins, in response to the naturally different diets offered to honeybees during the larval period.

  2. Humanized mouse models: Application to human diseases.

    Science.gov (United States)

    Ito, Ryoji; Takahashi, Takeshi; Ito, Mamoru

    2018-05-01

    Humanized mice are superior to rodents for preclinical evaluation of the efficacy and safety of drug candidates using human cells or tissues. During the past decade, humanized mouse technology has been greatly advanced by the establishment of novel platforms of genetically modified immunodeficient mice. Several human diseases can be recapitulated using humanized mice due to the improved engraftment and differentiation capacity of human cells or tissues. In this review, we discuss current advanced humanized mouse models that recapitulate human diseases including cancer, allergy, and graft-versus-host disease. © 2017 Wiley Periodicals, Inc.

  3. The complete mitochondrial genome of the common sea slater, Ligia oceanica (Crustacea, Isopoda bears a novel gene order and unusual control region features

    Directory of Open Access Journals (Sweden)

    Podsiadlowski Lars

    2006-09-01

    Full Text Available Abstract Background Sequence data and other characters from mitochondrial genomes (gene translocations, secondary structure of RNA molecules are useful in phylogenetic studies among metazoan animals from population to phylum level. Moreover, the comparison of complete mitochondrial sequences gives valuable information about the evolution of small genomes, e.g. about different mechanisms of gene translocation, gene duplication and gene loss, or concerning nucleotide frequency biases. The Peracarida (gammarids, isopods, etc. comprise about 21,000 species of crustaceans, living in many environments from deep sea floor to arid terrestrial habitats. Ligia oceanica is a terrestrial isopod living at rocky seashores of the european North Sea and Atlantic coastlines. Results The study reveals the first complete mitochondrial DNA sequence from a peracarid crustacean. The mitochondrial genome of Ligia oceanica is a circular double-stranded DNA molecule, with a size of 15,289 bp. It shows several changes in mitochondrial gene order compared to other crustacean species. An overview about mitochondrial gene order of all crustacean taxa yet sequenced is also presented. The largest non-coding part (the putative mitochondrial control region of the mitochondrial genome of Ligia oceanica is unexpectedly not AT-rich compared to the remainder of the genome. It bears two repeat regions (4× 10 bp and 3× 64 bp, and a GC-rich hairpin-like secondary structure. Some of the transfer RNAs show secondary structures which derive from the usual cloverleaf pattern. While some tRNA genes are putative targets for RNA editing, trnR could not be localized at all. Conclusion Gene order is not conserved among Peracarida, not even among isopods. The two isopod species Ligia oceanica and Idotea baltica show a similarly derived gene order, compared to the arthropod ground pattern and to the amphipod Parhyale hawaiiensis, suggesting that most of the translocation events were already

  4. Subdivision of arthropod cap-n-collar expression domains is restricted to Mandibulata

    Science.gov (United States)

    2014-01-01

    Background The monophyly of Mandibulata - the division of arthropods uniting pancrustaceans and myriapods - is consistent with several morphological characters, such as the presence of sensory appendages called antennae and the eponymous biting appendage, the mandible. Functional studies have demonstrated that the patterning of the mandible requires the activity of the Hox gene Deformed and the transcription factor cap-n-collar (cnc) in at least two holometabolous insects: the fruit fly Drosophila melanogaster and the beetle Tribolium castaneum. Expression patterns of cnc from two non-holometabolous insects and a millipede have suggested conservation of the labral and mandibular domains within Mandibulata. However, the activity of cnc is unknown in crustaceans and chelicerates, precluding understanding of a complete scenario for the evolution of patterning of this appendage within arthropods. To redress these lacunae, here we investigate the gene expression of the ortholog of cnc in Parhyale hawaiensis, a malacostracan crustacean, and two chelicerates: the harvestman Phalangium opilio, and the scorpion Centruroides sculpturatus. Results In the crustacean P. hawaiensis, the segmental expression of Ph-cnc is the same as that reported previously in hexapods and myriapods, with two distinct head domains in the labrum and the mandibular segment. In contrast, Po-cnc and Cs-cnc expression is not enriched in the labrum of either chelicerate, but instead is expressed at comparable levels in all appendages. In further contrast to mandibulate orthologs, the expression domain of Po-cnc posterior to the labrum is not confined within the expression domain of Po-Dfd. Conclusions Expression data from two chelicerate outgroup taxa suggest that the signature two-domain head expression pattern of cnc evolved at the base of Mandibulata. The observation of the archetypal labral and mandibular segment domains in a crustacean exemplar supports the synapomorphic nature of mandibulate cnc

  5. Cardiomyocytes derived from embryonic stem cells resemble cardiomyocytes of the embryonic heart tube

    NARCIS (Netherlands)

    Fijnvandraat, Arnoud C.; van Ginneken, Antoni C. G.; de Boer, Piet A. J.; Ruijter, Jan M.; Christoffels, Vincent M.; Moorman, Antoon F. M.; Lekanne Deprez, Ronald H.

    2003-01-01

    OBJECTIVE: After formation of the linear heart tube a chamber-specific program of gene expression becomes active that underlies the formation of the chamber myocardium. To assess whether this program is recapitulated in in vitro differentiated embryonic stem cells, we performed qualitative and

  6. Animal models of antineutrophil cytoplasm antibody-associated vasculitis.

    LENUS (Irish Health Repository)

    Salama, Alan D

    2012-01-01

    To provide an update on the experimental models that have been developed recapitulating clinical antineutrophil cytoplasm antibody (ANCA) associated vasculitis. The application of the models in the study of pathogenesis, and the therapeutic implications of this, are covered in the article by van Timmeren and Heeringa in this issue.

  7. AOM/DSS Model of Colitis-Associated Cancer.

    Science.gov (United States)

    Parang, Bobak; Barrett, Caitlyn W; Williams, Christopher S

    2016-01-01

    Our understanding of colitis-associated carcinoma (CAC) has benefited substantially from mouse models that faithfully recapitulate human CAC. Chemical models, in particular, have enabled fast and efficient analysis of genetic and environmental modulators of CAC without the added requirement of time-intensive genetic crossings. Here we describe the Azoxymethane (AOM)/Dextran Sodium Sulfate (DSS) mouse model of inflammatory colorectal cancer.

  8. Brain Wiring in the Fourth Dimension.

    Science.gov (United States)

    Wernet, Mathias F; Desplan, Claude

    2015-07-02

    In this issue of Cell, Langen et al. use time-lapse multiphoton microscopy to show how Drosophila photoreceptor growth cones find their targets. Based on the observed dynamics, they develop a simple developmental algorithm recapitulating the highly complex connectivity pattern of these neurons, suggesting a basic framework for establishing wiring specificity. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Argument z důsledku a jeho varianty (Argument from Consequences and its variants

    Directory of Open Access Journals (Sweden)

    Martina Juříková

    2016-03-01

    Full Text Available The article examines the use and evaluation of the argument from consequences, its historical origins since Aristotle through Blaise Pascal, David Hume until the inclusion of this argument into the textbooks of modern logic. The article also recapitulates current evaluation of this argument by Douglas Walton and along with Walton presents its two variants and criteria for evaluating their validity.

  10. Multi parton interactions and multi parton distributions in QCD

    International Nuclear Information System (INIS)

    Diehl, M.

    2012-01-01

    After a brief recapitulation of the general interest of parton densities, we discuss multiple hard interactions and multi parton distributions. We report on recent theoretical progress in their QCD description, on outstanding conceptual problems and on possibilities to use multi parton distributions as a laboratory to test and improve our understanding of hadron structure. (author)

  11. T-cells contribute to hypertension but not to renal injury in mice with subtotal nephrectomy

    NARCIS (Netherlands)

    Oosterhuis, Nynke R.; Papazova, Diana A.; Gremmels, Hendrik; Joles, Jaap A.; Verhaar, Marianne C.

    2017-01-01

    Background: The pathological condition of chronic kidney disease may not be adequately recapitulated in immunocompromised mice due to the lack of T-cells, which are important for the development of hypertension and renal injury. We studied the role of the immune system in relation to salt-sensitive

  12. iPSCs to the rescue in Alzheimer's research.

    Science.gov (United States)

    Choi, Se Hoon; Tanzi, Rudolph E

    2012-03-02

    A crucial limitation to our understanding of Alzheimer's disease has been the inability to test hypotheses on live, patient-specific neurons. A recent study in Nature by Israel et al. (2012) reports that iPSC-derived neurons from AD patients recapitulate multiple aspects of disease pathology. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Biomechanical Strain Exacerbates Inflammation on a Progeria-on-a-Chip Model

    NARCIS (Netherlands)

    Ribas, J.; Zhang, Y.S.; Pitrez, P.R.; Leijten, Jeroen Christianus Hermanus; Miscuglio, M.; Rouwkema, Jeroen; Dokmeci, M.R.; Nissan, X.; Ferreira, L.; Khademhosseini, A.

    2017-01-01

    A progeria-on-a-chip model is engineered to recapitulate the biomechanical dynamics of vascular disease and aging. The model shows an exacerbated injury response to strain and is rescued by pharmacological treatments. The progeria-on-a-chip is expected to drive the discovery of new drugs and to

  14. Embryonic stem cells as an ectodermal cellular model of human p63-related dysplasia syndromes.

    NARCIS (Netherlands)

    Rostagno, P.; Wolchinsky, Z.; Vigano, A.M.; Shivtiel, S.; Zhou, Huiqing; Bokhoven, J.H.L.M. van; Ferone, G.; Missero, C.; Mantovani, R.; Aberdam, D.; Virolle, T.

    2010-01-01

    Heterozygous mutations in the TP63 transcription factor underlie the molecular basis of several similar autosomal dominant ectodermal dysplasia (ED) syndromes. Here we provide a novel cellular model derived from embryonic stem (ES) cells that recapitulates in vitro the main steps of embryonic skin

  15. Practicing Good Habits, Grade 4.

    Science.gov (United States)

    Van Cong Lau; And Others

    This illustrated textbook was designed for teaching civics and values to fourth grade students in Vietnam. It is divided into six chapters: (1) At School (recapitulation of the grade three program, friendship, respect for the teacher, team work, discipline, honor); (2) In the Street: Traffic Regulations; (3) At Home (the extended family spirit,…

  16. Designer matrices for intestinal stem cell and organoid culture

    NARCIS (Netherlands)

    Gjorevski, Nikolce; Sachs, Norman; Manfrin, Andrea; Giger, Sonja; Bragina, Maiia E.; Ordóñez-Morán, Paloma; Clevers, Hans; Lutolf, Matthias P.

    2016-01-01

    Epithelial organoids recapitulate multiple aspects of real organs, making them promising models of organ development, function and disease. However, the full potential of organoids in research and therapy has remained unrealized, owing to the poorly defined animal-derived matrices in which they are

  17. Computer Simulation of Embryonic Systems: What can a virtual embryo teach us about developmental toxicity? (LA Conference on Computational Biology & Bioinformatics)

    Science.gov (United States)

    This presentation will cover work at EPA under the CSS program for: (1) Virtual Tissue Models built from the known biology of an embryological system and structured to recapitulate key cell signals and responses; (2) running the models with real (in vitro) or synthetic (in silico...

  18. A presentation of four cases of organisational learning in a steam cracker. An exploration of organisational learning.

    NARCIS (Netherlands)

    Pauwels, Fernando; Van Ruysseveldt, Joris

    2010-01-01

    In this paper we will first recapitulate our theoretical framework and provide a definition of organisational learning, which will be further expanded on, amongst others by making use of a number of criteria, which have been developed by the Orglearn research consortium. After this short theoretical

  19. On the Status of Logic in Piaget

    Science.gov (United States)

    Reginensi, Luc

    2004-01-01

    This article analyses the way in which Piaget links the analogy between the child and the primitive with a theory of the history of the sciences, that is, it analyses Piaget's version of Haeckel's principle in which ontogenesis recapitulates phylogenesis. From this analysis, we reconstitute the operations through which Piaget forms and expresses…

  20. The Greenhouse effect: from research to political action

    International Nuclear Information System (INIS)

    Bernard, A.; Charmant, A.; Ladoux, N.; Vielle, M.

    1992-01-01

    What would be the ecological and socio-economic consequences of the warming of the planet Earth. The greenhouse effect is better defined today, but evaluating the dangers is still a risky business which demands extreme caution. The study recapitulates the current state of knowledge, and the preventive measures under consideration, so as to encourage the examination of the question

  1. Generation of BAC Transgenic Epithelial Organoids

    NARCIS (Netherlands)

    Schwank, G.; Andersson-Rolf, A.; Koo, B.K.; Sasaki, N.; Clevers, H.

    2013-01-01

    Under previously developed culture conditions, mouse and human intestinal epithelia can be cultured and expanded over long periods. These so-called organoids recapitulate the three-dimensional architecture of the gut epithelium, and consist of all major intestinal cell types. One key advantage of

  2. Examples of electrostatic electron optics: The Farrand and Elektros microscopes and electron mirrors

    International Nuclear Information System (INIS)

    Hawkes, P.W.

    2012-01-01

    The role of Gertrude Rempfer in the design of the Farrand and Elektros microscopes is evoked. The study of electron mirror optics, aberration correction using mirrors and the development of microscopes employing electron mirrors are recapitulated, accompanied by a full bibliography, of earlier publications in particular.

  3. Squaramide-based supramolecular materials for three-dimensional cell culture of human induced pluripotent stem cells and their derivatives

    NARCIS (Netherlands)

    Tong, Ciqing; Liu, Tingxian; Saez Talens, Victorio; Noteborn, Willem E.M.; Sharp, Thomas H.; Hendrix, Marco M.R.M.; Voets, Ilja K.; Mummery, Christine L.; Orlova, Valeria V.; Kieltyka, Roxanne E.

    2018-01-01

    Synthetic hydrogel materials can recapitulate the natural cell microenvironment; however, it is equally necessary that the gels maintain cell viability and phenotype while permitting reisolation without stress, especially for use in the stem cell field. Here, we describe a family of synthetically

  4. Sex disparity in colonic adenomagenesis involves promotion by male hormones, not protection by female hormones

    NARCIS (Netherlands)

    Amos-Landgraf, James M.; Heijmans, Jarom; Wielenga, Mattheus C. B.; Dunkin, Elisa; Krentz, Kathy J.; Clipson, Linda; Ederveen, Antwan G.; Groothuis, Patrick G.; Mosselman, Sietse; Muncan, Vanesa; Hommes, Daniel W.; Shedlovsky, Alexandra; Dove, William F.; van den Brink, Gijs R.

    2014-01-01

    It recently has been recognized that men develop colonic adenomas and carcinomas at an earlier age and at a higher rate than women. In the Apc(Pirc/+) (Pirc) rat model of early colonic cancer, this sex susceptibility was recapitulated, with male Pirc rats developing twice as many adenomas as

  5. The initiation of embryonic-like collagen fibrillogenesis by adult human tendon fibroblasts when cultured under tension

    DEFF Research Database (Denmark)

    Bayer, Monika L; Yeung, Chin-Yan C; Kadler, Karl E

    2010-01-01

    Tendon fibroblasts synthesize collagen and form fibrils during embryonic development, but to what extent mature fibroblasts are able to recapitulate embryonic development and develop normal tendon structure is unknown. The present study examined the capability of mature human tendon fibroblasts t...

  6. Cortex shatters the glass ceiling.

    Science.gov (United States)

    Au, Edmund; Fishell, Gord

    2008-11-06

    Recreating developmental structures in vitro has been a primary challenge for stem cell biologists. Recent studies in Cell Stem Cell (Eiraku et al., 2008) and Nature (Gaspard et al., 2008) demonstrate that embryonic stem cells can recapitulate early cortical development, enabling them to generate specific cortical subtypes.

  7. Variants in Nebulin (NEB) Are Linked to the Development of Familial Primary Angle Closure Glaucoma in Basset Hounds

    NARCIS (Netherlands)

    Ahram, D.F.; Grozdanic, S.D.; Kecova, H.; Henkes, A.; Collin, R.W.J.; Kuehn, M.H.

    2015-01-01

    Several dog breeds are susceptible to developing primary angle closure glaucoma (PACG), which suggests a genetic basis for the disease. We have identified a four-generation Basset Hound pedigree with characteristic autosomal recessive PACG that closely recapitulates PACG in humans. Our aim is to

  8. Gastroesophageal and biliary reflux. 10

    International Nuclear Information System (INIS)

    Bares, Roland; Buell, Udalrich

    1991-01-01

    After a brief recapitulation of reflux pathogenesis, this review presents the state of the art of nuclear medicine techniques to diagnose gastroesophageal or duodenogastric reflux, as well as a summary of clinical results and considerations about indication. (author).53 refs.; 5 figs.; 8 tabs

  9. Building Your Instrumental Music Program in an Urban School

    Science.gov (United States)

    Mixon, Kevin

    2005-01-01

    MENC has recently, recapitulated its vision of "Music for All" in its strategic plan, which warns that "30 to 50 per cent of new teachers who work in urban areas leave the field in their first three years of service.'' This undoubtedly affects instrumental music instruction for urban children. Collegial sharing is one solution to problems…

  10. 9 CFR 203.4 - Statement with respect to the disposition of records by packers, live poultry dealers, stockyard...

    Science.gov (United States)

    2010-01-01

    ... sheets; scale tickets received from others; inventory and products in storage; receiving records; trial... slips; production or sale tonnage reports (including recapitulations and summaries of routes, branches... sales invoices, or claims or credit memoranda; and Provided further, That microfilm copies of records...

  11. Systems Toxicology of Embryo Development (9th Copenhagen Workshop)

    Science.gov (United States)

    An important consideration for predictive toxicology is to identify developmental hazards utilizing mechanism-based in vitro assays (e.g., ToxCast) and in silico multiscale models. Steady progress has been made with agent-based models that recapitulate morphogenetic drivers for a...

  12. An investigation of brand choice processes

    NARCIS (Netherlands)

    Wierenga, B.

    1974-01-01

    Here a brief recapitulation of the study of brand choice processes is given, and the major conclusions are reported.

    In chapter 2 we discussed the empirical brand choice data used throughout the study. We saw that these were purchase histories of members of the Dutch Attwood

  13. The bio in the ink : cartilage regeneration with bioprintable hydrogels and articular cartilage-derived progenitor cells

    NARCIS (Netherlands)

    Levato, Riccardo; Webb, William R; Otto, Iris A; Mensinga, Anneloes; Zhang, Yadan; van Rijen, Mattie; van Weeren, P. René; Khan, Ilyas M.; Malda, Jos

    2017-01-01

    Cell-laden hydrogels are the primary building blocks for bioprinting, and, also termed bioinks, are the foundations for creating structures that can potentially recapitulate the architecture of articular cartilage. To be functional, hydrogel constructs need to unlock the regenerative capacity of

  14. Current and anticipated uses of the CATHARE code at EDF and FRAMATOME

    Energy Technology Data Exchange (ETDEWEB)

    Gandrille, J.L.; Vacher, J.L.; Poizat, F.

    1997-07-01

    This paper presents current industrial applications of the CATHARE code in the fields of Safety Studies and Simulators where the code is intensively used by FRAMATOME, EDF and CEA, the development partners of CATHARE. Future needs in these fields are also recapitulated.

  15. Multiparton interactions and multiparton distributions in QCD

    Energy Technology Data Exchange (ETDEWEB)

    Diehl, Markus

    2011-11-15

    After a brief recapitulation of the general interest of parton densities, we discuss multiple hard interactions and multiparton distributions. We report on recent theoretical progress in their QCD description, on outstanding conceptual problems and on possibilities to use multiparton distributions as a laboratory to test and improve our understanding of hadron structure. (orig.)

  16. Prognostic factors in pediatric pulmonary arterial hypertension : A systematic review and meta-analysis

    NARCIS (Netherlands)

    Ploegstra, Mark-Jan; Zijlstra, Willemijn M. H.; Douwes, Johannes M.; Hillege, Hans L.; Berger, Rolf M. F.

    2015-01-01

    BACKGROUND: Despite the introduction of targeted therapies in pediatric pulmonary arterial hypertension (PAH), prognosis remains poor. For the definition of treatment strategies and guidelines, there is a high need for an evidence-based recapitulation of prognostic factors. The aim of this study was

  17. Remodeling of cortical bone allografts mediated by adherent rAAV-RANKL and VEGF gene therapy

    DEFF Research Database (Denmark)

    Ito, H; Koefoed, M; Tiyapatanaputi, P

    2005-01-01

    Structural allograft healing is limited because of a lack of vascularization and remodeling. To study this we developed a mouse model that recapitulates the clinical aspects of live autograft and processed allograft healing. Gene expression analyses showed that there is a substantial decrease in ...

  18. Quantitative imaging of epithelial cell scattering identifies specific inhibitors of cell motility and cell-cell dissociation

    NARCIS (Netherlands)

    Loerke, D.; le Duc, Q.; Blonk, I.; Kerstens, A.; Spanjaard, E.; Machacek, M.; Danuser, G.; de Rooij, J.

    2012-01-01

    The scattering of cultured epithelial cells in response to hepatocyte growth factor (HGF) is a model system that recapitulates key features of metastatic cell behavior in vitro, including disruption of cell-cell adhesions and induction of cell migration. We have developed image analysis tools that

  19. Main conclusions of a seminar on managing technical resources in a changing nuclear industry

    International Nuclear Information System (INIS)

    Storey, P.D.

    2000-01-01

    The author recapitulates the different points from I Mech E Conference (Managing Technical resources in a changing Nuclear Industry -London, 29 September 1999), as following: UK position, BNFL Magnox and AEAT, UK view from BEGL, view from WANO, UK view from UKAEA, USA view from PECO Energy, and view from OECD NEA

  20. Clubbed fingers: the claws we lost?

    NARCIS (Netherlands)

    Brouwers, A.A.M.; Vermeij-Keers, C.; Zoelen, E.J.J. van; Gooren, L.J.G.

    2004-01-01

    Clubbed digits resemble the human embryonic fingers and toes, which took like the digits of a claw. Clubbed digits, thus, may represent the return of the embryonic claw and may even represent the claws man has lost during evolution, if ontogenesis realty recapitulates phylogenesis. We put forward

  1. Cosmopolitan Democracy: A Restatement

    Science.gov (United States)

    Archibugi, Daniele

    2012-01-01

    Can democracy be expanded beyond borders? For many years, it was taken for granted that the norms and values of democracy could be applied within the boundaries of a state only. But over the last 20 years, it has been increasingly argued that democracy can also inform international organizations and global politics. This article recapitulates the…

  2. Organoid cultures derived from patients with advanced prostate cancer

    NARCIS (Netherlands)

    Gao, Dong; Vela, Ian; Sboner, Andrea; Iaquinta, Phillip J; Karthaus, Wouter R; Gopalan, Anuradha; Dowling, Catherine; Wanjala, Jackline N; Undvall, Eva A; Arora, Vivek K; Wongvipat, John; Kossai, Myriam; Ramazanoglu, Sinan; Barboza, Luendreo P; Di, Wei; Cao, Zhen; Zhang, Qi Fan; Sirota, Inna; Ran, Leili; MacDonald, Theresa Y; Beltran, Himisha; Mosquera, Juan-Miguel; Touijer, Karim A; Scardino, Peter T; Laudone, Vincent P; Curtis, Kristen R; Rathkopf, Dana E; Morris, Michael J; Danila, Daniel C; Slovin, Susan F; Solomon, Stephen B; Eastham, James A; Chi, Ping; Carver, Brett; Rubin, Mark A; Scher, Howard I; Clevers, Hans; Sawyers, Charles L; Chen, Yu

    2014-01-01

    The lack of in vitro prostate cancer models that recapitulate the diversity of human prostate cancer has hampered progress in understanding disease pathogenesis and therapy response. Using a 3D organoid system, we report success in long-term culture of prostate cancer from biopsy specimens and

  3. The Value of Vitalism and Schrodinger's "What Is Life?" in the Contemporary Classroom

    Science.gov (United States)

    Sitaraman, Ramakrishnan

    2009-01-01

    Classic experiments and novel ideas in the history of science are often mentioned in passing in contemporary college-level science curricula. This study indicates that the detailed and creative recapitulation of a few well-chosen and famous, if well-known, results and ideas has the potential to increase students' understanding and appreciation of…

  4. Remote Access: A Vision for Mobile Medical Devices

    Directory of Open Access Journals (Sweden)

    Herbert Ernst

    2005-11-01

    Full Text Available During the Symposium for Remote Engineering and Virtual Instrumentation held at Brasov in early July 2005 an outlook was presented regarding the future potential of remote engineering for mobile medical devices. It is the intention of this article to recapitulate the content of the initiated discussions and to stimulate work in this complex and until now largely neglected field of application.

  5. Computational Model of Secondary Palate Fusion and Disruption

    Science.gov (United States)

    Morphogenetic events are driven by cell-generated physical forces and complex cellular dynamics. To improve our capacity to predict developmental effects from cellular alterations, we built a multi-cellular agent-based model in CompuCell3D that recapitulates the cellular networks...

  6. Microbands and clustered microbands in rolled copper

    DEFF Research Database (Denmark)

    Leffers, T.; Ananthan, V.S.; Christoffersen, H.

    2001-01-01

    First we recapitulate the present knowledge about microbands (MB2s). On this basis we suggest that the grains with profuse microbanding may deform with slip on one single slip plane. This suggestion is substantiated by the observation of clustered MB2s. Furthermore we show that the MB2 walls cons...... consist of a loosely knit dislocation network....

  7. Current and anticipated uses of the CATHARE code at EDF and FRAMATOME

    International Nuclear Information System (INIS)

    Gandrille, J.L.; Vacher, J.L.; Poizat, F.

    1997-01-01

    This paper presents current industrial applications of the CATHARE code in the fields of Safety Studies and Simulators where the code is intensively used by FRAMATOME, EDF and CEA, the development partners of CATHARE. Future needs in these fields are also recapitulated

  8. D-galactose-induced brain ageing model

    DEFF Research Database (Denmark)

    Sadigh-Eteghad, Saeed; Majdi, Alireza; McCann, Sarah K.

    2017-01-01

    Animal models are commonly used in brain ageing research. Amongst these, models where rodents are exposed to d-galactose are held to recapitulate a number of features of ageing including neurobehavioral and neurochemical changes. However, results from animal studies are often inconsistent...

  9. Isolation and differentiation of stromal vascular cells to beige/brite cells

    DEFF Research Database (Denmark)

    Aune, Ulrike Liisberg; Ruiz, Lauren; Kajimura, Shingo

    2013-01-01

    cold exposure or by PPARγ agonists, therefore, this cell type has potential as a therapeutic target for obesity treatment. Although most immortalized adipocyte lines cannot recapitulate the process of "browning" of white fat in culture, primary adipocytes isolated from stromal vascular fraction...

  10. Generation of an inducible colon-specific Cre enzyme mouse line for colon cancer research

    NARCIS (Netherlands)

    Tetteh, Paul W.; Kretzschmar, Kai; Begthel, Harry; Van Den Born, Maaike; Korving, Jeroen; Morsink, Folkert; Farin, Henner; Van Es, Johan H.; Offerhaus, G. Johan A; Clevers, Hans

    2016-01-01

    Current mouse models for colorectal cancer often differ significantly from human colon cancer, being largely restricted to the small intestine. Here, we aim to develop a colon-specific inducible mouse model that can faithfully recapitulate human colon cancer initiation and progression. Carbonic

  11. Multiparton interactions and multiparton distributions in QCD

    International Nuclear Information System (INIS)

    Diehl, Markus

    2011-11-01

    After a brief recapitulation of the general interest of parton densities, we discuss multiple hard interactions and multiparton distributions. We report on recent theoretical progress in their QCD description, on outstanding conceptual problems and on possibilities to use multiparton distributions as a laboratory to test and improve our understanding of hadron structure. (orig.)

  12. Robust Praxialism and the Anti-Aesthetic Turn

    Science.gov (United States)

    Alperson, Philip

    2010-01-01

    In this paper I retrace the line of thought that led me to the position of a praxial philosophy of music education, from a perspective 20 years after the inaugural meeting of the International Society for the Philosophy of Music Education. I discuss how I conceive of the general project of the philosophy of music education and recapitulate some of…

  13. Unsettling Melodies: A Cognitive Approach to Incongruent Film Music

    NARCIS (Netherlands)

    Willemsen, Steven; Kiss, Miklós

    2013-01-01

    Incongruent film music is a soundtrack, either diegetic or non- diegetic, which expresses qualities that stand in contrast to the emotions evoked by the events seen. The present article aims at covering two interconnected areas; the first is comprised of a critical recapitulation of available

  14. Paving the way towards complex blood-brain barrier models using pluripotent stem cells

    DEFF Research Database (Denmark)

    Lauschke, Karin; Frederiksen, Lise; Hall, Vanessa Jane

    2017-01-01

    , it is now possible to produce many cell types from the BBB and even partially recapitulate this complex tissue in vitro. In this review, we summarize the most recent developments in PSC differentiation and modelling of the BBB. We also suggest how patient-specific human induced PSCs could be used to model...

  15. A survey of computer-based approaches for greenhouse climate management.

    NARCIS (Netherlands)

    Schotman, P.J.

    1996-01-01

    This study recapitulates research efforts that have addressed the restricted problem of greenhouse climate management. This problem is first analyzed by looking at the current working method of the grower and the characteristics of this management task. The different attempts to automate parts of

  16. Communication and Education in a Virtual World: Avatar-Mediated Teaching and Learning in Second Life

    Science.gov (United States)

    Mon, Lorri

    2010-01-01

    Education within Second Life frequently recapitulates the "sage on the stage" as students sit their avatars down in chairs in the virtual world and listen to or read an instructor's lecture while watching a slideshow. This conceptual article explores alternative active learning techniques supporting independent and collaborative learning…

  17. Kisspeptins: bridging energy homeostasis and reproduction

    DEFF Research Database (Denmark)

    Castellano, Juan M; Bentsen, Agnete H; Mikkelsen, Jens D

    2010-01-01

    RH neurons. This review recapitulates the experimental evidence obtained to date, mostly in laboratory rodents, supporting the function of kisspeptins in bridging energy balance and reproduction, with special emphasis on recent developments in this field, such as the recognition of mTOR (mammalian target...

  18. Periarteriolar Glioblastoma Stem Cell Niches Express Bone Marrow Hematopoietic Stem Cell Niche Proteins

    NARCIS (Netherlands)

    Hira, Vashendriya V. V.; Wormer, Jill R.; Kakar, Hala; Breznik, Barbara; van der Swaan, Britt; Hulsbos, Renske; Tigchelaar, Wikky; Tonar, Zbynek; Khurshed, Mohammed; Molenaar, Remco J.; van Noorden, Cornelis J. F.

    2018-01-01

    In glioblastoma, a fraction of malignant cells consists of therapy-resistant glioblastoma stem cells (GSCs) residing in protective niches that recapitulate hematopoietic stem cell (HSC) niches in bone marrow. We have previously shown that HSC niche proteins stromal cell-derived factor-1α (SDF-1α),

  19. Why Is She Naked?

    DEFF Research Database (Denmark)

    Rodil, Kasper; Winschiers-Theophilus, Heike

    2018-01-01

    with a refinement of the previously presented Tripartite Digitisation Model (TDM). We begin by providing a short recapitulation of the TDM originally published in Vol. 10, with an emphasis on the role of evaluations. This model is exemplified with a concrete example of digitisation of ICH together with an Ova...

  20. A Nineteenth-Century French Proposal to Use School Vouchers.

    Science.gov (United States)

    Van Vliet, W.; Smyth, J. A.

    1982-01-01

    In light of the current American interest in school vouchers as proposed by economist Milton Friedman, recapitulates the origins, content, and fate of an 1872 law drafted by a French parliamentary commission to establish a countrywide voucher scheme for primary schools. (NEC)

  1. Loss-less Nano-fractionator for High Sensitivity, High Coverage Proteomics

    DEFF Research Database (Denmark)

    Kulak, Nils A; Geyer, Philipp E; Mann, Matthias

    2017-01-01

    automated and in-depth characterization of 12 different human cell lines to a median depth of 11,472 different proteins, which revealed differences recapitulating their developmental origin and differentiation status. The fractionation technology described here is flexible, easy to use, and facilitates...

  2. The Oncopig Cancer Model: An Innovative Large Animal Translational Oncology Platform

    DEFF Research Database (Denmark)

    Schachtschneider, Kyle M.; Schwind, Regina M.; Newson, Jordan

    2017-01-01

    -the Oncopig Cancer Model (OCM)-as a next-generation large animal platform for the study of hematologic and solid tumor oncology. With mutations in key tumor suppressor and oncogenes, TP53R167H and KRASG12D , the OCM recapitulates transcriptional hallmarks of human disease while also exhibiting clinically...

  3. Space Time Quantization and the Big Bang

    OpenAIRE

    Sidharth, B. G.

    1998-01-01

    A recent cosmological model is recapitulated which deduces the correct mass, radius and age of the universe as also the Hubble constant and other well known apparently coincidental relations. It also predicts an ever expanding accelerating universe as is confirmed by latest supernovae observations. Finally the Big Bang model is recovered as a suitable limiting case.

  4. YAP/TAZ-Dependent Reprogramming of Colonic Epithelium Links ECM Remodeling to Tissue Regeneration

    DEFF Research Database (Denmark)

    Yui, Shiro; Azzolin, Luca; Maimets, Martti

    2018-01-01

    by remodeling the extracellular matrix (ECM), increased FAK/Src signaling, and ultimately YAP/TAZ activation. In a defined cell culture system recapitulating the extracellular matrix remodeling observed in vivo, we show that a collagen 3D matrix supplemented with Wnt ligands is sufficient to sustain endogenous...

  5. Synthesis and Chemistry of Organic Geminal Di- and Triazides.

    Science.gov (United States)

    Häring, Andreas P; Kirsch, Stefan F

    2015-11-06

    This review recapitulates all available literature dealing with the synthesis and reactivity of geminal organic di- and triazides. These compound classes are, to a large extent, unexplored despite their promising chemical properties and their simple preparation. In addition, the chemistry of carbonyl diazide (2) and tetraazidomethane (105) is described in separate sections.

  6. Implications of a neural network model of early sensori-motor development for the field of developmental neurology

    NARCIS (Netherlands)

    van Heijst, JJ; Touwen, BCL; Vos, JE

    This paper reports on a neural network model for early sensori-motor development and on the possible implications of this research for our understanding and, eventually, treatment of motor disorders like cerebral palsy. We recapitulate the results we published in detail in a series of papers [1-4].

  7. Personalized Proteome Profiles of Healthy and Tumor Human Colon Organoids Reveal Both Individual Diversity and Basic Features of Colorectal Cancer

    NARCIS (Netherlands)

    Cristobal, Alba; van den Toorn, Henk W.P.; van de Wetering, Marc; Clevers, Hans; Heck, Albert J R; Mohammed, Shabaz

    2017-01-01

    Diseases at the molecular level are complex and patient dependent, necessitating development of strategies that enable precision treatment to optimize clinical outcomes. Organoid technology has recently been shown to have the potential to recapitulate the in vivo characteristics of the original

  8. Personalized Proteome Profiles of Healthy and Tumor Human Colon Organoids Reveal Both Individual Diversity and Basic Features of Colorectal Cancer

    NARCIS (Netherlands)

    Cristobal Gonzalez de Durana, Alba|info:eu-repo/dai/nl/338769706; van den Toorn, Henk W P|info:eu-repo/dai/nl/31093205X; van de Wetering, Marc; Clevers, Hans|info:eu-repo/dai/nl/07164282X; Heck, Albert J R|info:eu-repo/dai/nl/105189332; Mohammed, Shabaz|info:eu-repo/dai/nl/30483632X

    2017-01-01

    Diseases at the molecular level are complex and patient dependent, necessitating development of strategies that enable precision treatment to optimize clinical outcomes. Organoid technology has recently been shown to have the potential to recapitulate the in vivo characteristics of the original

  9. Markers of murine embryonic and neural stem cells, neurons and astrocytes: reference points for developmental neurotoxicity testing

    Science.gov (United States)

    Developmental neurotoxicity (DNT) is a significant concern for environmental chemicals, as well as for food and drug constituents. The sensitivity of animal-based DNT models is unclear, and they are expensive and time consuming. Murine embryonic stem cells (mESC) recapitulate sev...

  10. IN VITRO SCREENING OF DEVELOPMENTAL NEUROTOXICANTS IN RAT PRIMARY CORTICAL NEURONS USING HIGH CONTENT IMAGE

    Science.gov (United States)

    There is a need for more efficient and cost-effective methods for identifying, characterizing and prioritizing chemicals which may result in developmental neurotoxicity. One approach is to utilize in vitro test systems which recapitulate the critical processes of nervous system d...

  11. Zebrafish brd2a and brd2b are paralogous members of the bromodomain-ET (BET family of transcriptional coregulators that show structural and expression divergence

    Directory of Open Access Journals (Sweden)

    Bee Katharine J

    2008-04-01

    Full Text Available Abstract Background Brd2 belongs to the bromodomain-extraterminal domain (BET family of transcriptional co-regulators, and functions as a pivotal histone-directed recruitment scaffold in chromatin modification complexes affecting signal-dependent transcription. Brd2 facilitates expression of genes promoting proliferation and is implicated in apoptosis and in egg maturation and meiotic competence in mammals; it is also a susceptibility gene for juvenile myoclonic epilepsy (JME in humans. The brd2 ortholog in Drosophila is a maternal effect, embryonic lethal gene that regulates several homeotic loci, including Ultrabithorax. Despite its importance, there are few systematic studies of Brd2 developmental expression in any organism. To help elucidate both conserved and novel gene functions, we cloned and characterized expression of brd2 cDNAs in zebrafish, a vertebrate system useful for genetic analysis of development and disease, and for study of the evolution of gene families and functional diversity in chordates. Results We identify cDNAs representing two paralogous brd2 loci in zebrafish, brd2a on chromosome 19 and brd2b on chromosome 16. By sequence similarity, syntenic and phylogenetic analyses, we present evidence for structural divergence of brd2 after gene duplication in fishes. brd2 paralogs show potential for modular domain combinations, and exhibit distinct RNA expression patterns throughout development. RNA in situ hybridizations in oocytes and embryos implicate brd2a and brd2b as maternal effect genes involved in egg polarity and egg to embryo transition, and as zygotic genes important for development of the vertebrate nervous system and for morphogenesis and differentiation of the digestive tract. Patterns of brd2 developmental expression in zebrafish are consistent with its proposed role in Homeobox gene regulation. Conclusion Expression profiles of zebrafish brd2 paralogs support a role in vertebrate developmental patterning and

  12. Aging stem cells. A Werner syndrome stem cell model unveils heterochromatin alterations as a driver of human aging.

    Science.gov (United States)

    Zhang, Weiqi; Li, Jingyi; Suzuki, Keiichiro; Qu, Jing; Wang, Ping; Zhou, Junzhi; Liu, Xiaomeng; Ren, Ruotong; Xu, Xiuling; Ocampo, Alejandro; Yuan, Tingting; Yang, Jiping; Li, Ying; Shi, Liang; Guan, Dee; Pan, Huize; Duan, Shunlei; Ding, Zhichao; Li, Mo; Yi, Fei; Bai, Ruijun; Wang, Yayu; Chen, Chang; Yang, Fuquan; Li, Xiaoyu; Wang, Zimei; Aizawa, Emi; Goebl, April; Soligalla, Rupa Devi; Reddy, Pradeep; Esteban, Concepcion Rodriguez; Tang, Fuchou; Liu, Guang-Hui; Belmonte, Juan Carlos Izpisua

    2015-06-05

    Werner syndrome (WS) is a premature aging disorder caused by WRN protein deficiency. Here, we report on the generation of a human WS model in human embryonic stem cells (ESCs). Differentiation of WRN-null ESCs to mesenchymal stem cells (MSCs) recapitulates features of premature cellular aging, a global loss of H3K9me3, and changes in heterochromatin architecture. We show that WRN associates with heterochromatin proteins SUV39H1 and HP1α and nuclear lamina-heterochromatin anchoring protein LAP2β. Targeted knock-in of catalytically inactive SUV39H1 in wild-type MSCs recapitulates accelerated cellular senescence, resembling WRN-deficient MSCs. Moreover, decrease in WRN and heterochromatin marks are detected in MSCs from older individuals. Our observations uncover a role for WRN in maintaining heterochromatin stability and highlight heterochromatin disorganization as a potential determinant of human aging. Copyright © 2015, American Association for the Advancement of Science.

  13. Manipulation of in vitro collagen matrix architecture for scaffolds of improved physiological relevance

    Science.gov (United States)

    Hapach, Lauren A.; VanderBurgh, Jacob A.; Miller, Joseph P.; Reinhart-King, Cynthia A.

    2015-12-01

    Type I collagen is a versatile biomaterial that is widely used in medical applications due to its weak antigenicity, robust biocompatibility, and its ability to be modified for a wide array of applications. As such, collagen has become a major component of many tissue engineering scaffolds, drug delivery platforms, and substrates for in vitro cell culture. In these applications, collagen constructs are fabricated to recapitulate a diverse set of conditions. Collagen fibrils can be aligned during or post-fabrication, cross-linked via numerous techniques, polymerized to create various fibril sizes and densities, and copolymerized into a wide array of composite scaffolds. Here, we review approaches that have been used to tune collagen to better recapitulate physiological environments for use in tissue engineering applications and studies of basic cell behavior. We discuss techniques to control fibril alignment, methods for cross-linking collagen constructs to modulate stiffness, and composite collagen constructs to better mimic physiological extracellular matrix.

  14. Reverse engineering the mechanical and molecular pathways in stem cell morphogenesis.

    Science.gov (United States)

    Lu, Kai; Gordon, Richard; Cao, Tong

    2015-03-01

    The formation of relevant biological structures poses a challenge for regenerative medicine. During embryogenesis, embryonic cells differentiate into somatic tissues and undergo morphogenesis to produce three-dimensional organs. Using stem cells, we can recapitulate this process and create biological constructs for therapeutic transplantation. However, imperfect imitation of nature sometimes results in in vitro artifacts that fail to recapitulate the function of native organs. It has been hypothesized that developing cells may self-organize into tissue-specific structures given a correct in vitro environment. This proposition is supported by the generation of neo-organoids from stem cells. We suggest that morphogenesis may be reverse engineered to uncover its interacting mechanical pathway and molecular circuitry. By harnessing the latent architecture of stem cells, novel tissue-engineering strategies may be conceptualized for generating self-organizing transplants. Copyright © 2013 John Wiley & Sons, Ltd.

  15. Molecular phenotyping of human ovarian cancer stem cells unravels the mechanisms for repair and chemoresistance

    DEFF Research Database (Denmark)

    Alvero, Ayesha B; Chen, Rui; Fu, Han-Hsuan

    2009-01-01

    A major burden in the treatment of ovarian cancer is the high percentage of recurrence and chemoresistance. Cancer stem cells (CSCs) provide a reservoir of cells that can self-renew, can maintain the tumor by generating differentiated cells [non-stem cells (non-CSCs)] which make up the bulk...... to form spheroids in suspension, and the ability to recapitulate in vivo the original tumor. Chemotherapy eliminates the bulk of the tumor but it leaves a core of cancer cells with high capacity for repair and renewal. The molecular properties identified in these cells may explain some of the unique...... of the tumor and may be the primary source of recurrence. We describe the characterization of human ovarian cancer stem cells (OCSCs). These cells have a distinctive genetic profile that confers them with the capacity to recapitulate the original tumor, proliferate with chemotherapy, and promote recurrence...

  16. A multifunctional 3D co-culture system for studies of mammary tissue morphogenesis and stem cell biology.

    Directory of Open Access Journals (Sweden)

    Jonathan J Campbell

    Full Text Available Studies on the stem cell niche and the efficacy of cancer therapeutics require complex multicellular structures and interactions between different cell types and extracellular matrix (ECM in three dimensional (3D space. We have engineered a 3D in vitro model of mammary gland that encompasses a defined, porous collagen/hyaluronic acid (HA scaffold forming a physiologically relevant foundation for epithelial and adipocyte co-culture. Polarized ductal and acinar structures form within this scaffold recapitulating normal tissue morphology in the absence of reconstituted basement membrane (rBM hydrogel. Furthermore, organoid developmental outcome can be controlled by the ratio of collagen to HA, with a higher HA concentration favouring acinar morphological development. Importantly, this culture system recapitulates the stem cell niche as primary mammary stem cells form complex organoids, emphasising the utility of this approach for developmental and tumorigenic studies using genetically altered animals or human biopsy material, and for screening cancer therapeutics for personalised medicine.

  17. Water Buffalo (Bubalus bubalis) as a spontaneous animal model of Vitiligo.

    Science.gov (United States)

    Singh, Vijay Pal; Motiani, Rajender K; Singh, Archana; Malik, Garima; Aggarwal, Rangoli; Pratap, Kunal; Wani, Mohan R; Gokhale, Suresh B; Natarajan, Vivek T; Gokhale, Rajesh S

    2016-07-01

    Vitiligo is a multifactorial acquired depigmenting disorder. Recent insights into the molecular mechanisms driving the gradual destruction of melanocytes in vitiligo will likely lead to the discovery of novel therapies, which need to be evaluated in animal models that closely recapitulate the pathogenesis of human vitiligo. In humans, vitiligo is characterized by a spontaneous loss of functional melanocytes from the epidermis, but most animal models of vitiligo are either inducible or genetically programmed. Here, we report that acquired depigmentation in water buffalo recapitulates molecular, histological, immunohistochemical, and ultrastructural changes observed in human vitiligo and hence could be used as a model to study vitiligo pathogenesis and facilitate the discovery and evaluation of therapeutic interventions for vitiligo. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Organoid technology for brain and therapeutics research.

    Science.gov (United States)

    Wang, Zhi; Wang, Shu-Na; Xu, Tian-Ying; Miao, Zhu-Wei; Su, Ding-Feng; Miao, Chao-Yu

    2017-10-01

    Brain is one of the most complex organs in human. The current brain research is mainly based on the animal models and traditional cell culture. However, the inherent species differences between humans and animals as well as the gap between organ level and cell level make it difficult to study human brain development and associated disorders through traditional technologies. Recently, the brain organoids derived from pluripotent stem cells have been reported to recapitulate many key features of human brain in vivo, for example recapitulating the zone of putative outer radial glia cells. Brain organoids offer a new platform for scientists to study brain development, neurological diseases, drug discovery and personalized medicine, regenerative medicine, and so on. Here, we discuss the progress, applications, advantages, limitations, and prospects of brain organoid technology in neurosciences and related therapeutics. © 2017 John Wiley & Sons Ltd.

  19. C. elegans model of neuronal aging

    OpenAIRE

    Peng, Chiu-Ying; Chen, Chun-Hao; Hsu, Jiun-Min; Pan, Chun-Liang

    2011-01-01

    Aging of the nervous system underlies the behavioral and cognitive decline associated with senescence. Understanding the molecular and cellular basis of neuronal aging will therefore contribute to the development of effective treatments for aging and age-associated neurodegenerative disorders. Despite this pressing need, there are surprisingly few animal models that aim at recapitulating neuronal aging in a physiological context. We recently developed a C. elegans model of neuronal aging, and...

  20. Delivery 7 Report on the impact of conflicts/synergies and policy proposals for implementing the EU Action Plan in member states

    DEFF Research Database (Denmark)

    Beck, Anne-Marie Tyroll; Michelsen, Johannes

    This report on “Implementing the European Organic Action Plan in EU member states - stakeholders’ perceptions of implementation problems and coping strategies” recapitulates the results of a series of national workshops undertaken in winter/spring 2007. It brings together very different views...... and perceptions on organic action plans and possible evaluation methodologies and can be seen as ORGAP’s stakeholder oriented or public oriented step....

  1. Chelation and flotation in endodontic practice: an update.

    Science.gov (United States)

    Stewart, G G

    1986-10-01

    The removal of broken instruments and silver points, as well as pulp tissue, may be accomplished by careful instrumentation, irrigation, and flotation. Flotation and recapitulation with smaller instruments and irrigation with copious amounts of sodium hypochlorite can clean out microorganisms and the organic matter from the tubular structure which provides a more ideal surface for sealing the root canal system. A sterile environment was obtained by removing the substrate and creating a more ideal environment for better healing.

  2. [Hyperammonemia type II as an example of urea cycle disorder].

    Science.gov (United States)

    Hawrot-Kawecka, Anna M; Kawecki, Grzegorz P; Duława, Jan

    2006-01-01

    Ornithine transcarbamylase deficiency is the most common inherited urea cycle disorder. Its clinical manifestations as lethargy, vomites, coma and cerebral edema are the effect of the higher concentration of the ammonia in plasma. Hyperammonemia, caused by mutation in ornithine transcarbamylase gene, is often considered as a reason of coma by pediatricians but skipped by internist, although it is the third reason of hepatic coma in adults. This article is the recapitulation of published studies and their implication on everyday clinical practice.

  3. Administration of vitamin K does not counteract the ectopic mineralization of connective tissues in Abcc6−/− mice, a model for pseudoxanthoma elasticum

    OpenAIRE

    Jiang, Qiujie; Li, Qiaoli; Grand-Pierre, Alix E; Schurgers, Leon J; Uitto, Jouni

    2011-01-01

    Pseudoxanthoma elasticum (PXE) is a heritable multisystem disorder manifesting with ectopic calcification of peripheral connective tissues, caused by mutations in the ABCC6 gene. Alterations in vitamin K metabolism have been suggested to contribute to the pathomechanisms of the mineralization process. In this study we administered vitamin K or its glutathione conjugate (K3-GSH) into Abcc6−/− mice that recapitulate features of PXE. Oral administration of vitamin K2, in dosages that vastly exce...

  4. Animal models for Gaucher disease research

    OpenAIRE

    Farfel-Becker, Tamar; Vitner, Einat B.; Futerman, Anthony H.

    2011-01-01

    Gaucher disease (GD), the most common lysosomal storage disorder (LSD), is caused by the defective activity of the lysosomal hydrolase glucocerebrosidase, which is encoded by the GBA gene. Generation of animal models that faithfully recapitulate the three clinical subtypes of GD has proved to be more of a challenge than first anticipated. The first mouse to be produced died within hours after birth owing to skin permeability problems, and mice with point mutations in Gba did not display sympt...

  5. Rapid In Vivo Validation of Tumor Suppressor Gene Function in Prostate Cancer Progression

    Science.gov (United States)

    2016-07-01

    identification of the best sgRNA sequences and accelerated our ability to move to the in vivo studies proposed in Aim2. Our goal was to use CRISPR / Cas ...and to initiate prostate cancer in the mouse after injection of lentiviral particles expressing CRISPR / Cas components and Cre recombinase. Our initial...in vivo Our goal was to use CRISPR / Cas lentiviral transduction of the adult prostate to inactivate p53 or Rb. We aimed to recapitulate the effects of

  6. Determination of {alpha}{sub s} from Gross-Llewellyn Smith sum rule by accounting for infrared renormalon

    Energy Technology Data Exchange (ETDEWEB)

    Contreras, C [Department of Physics, Universidad Tecn. Federico Santa Maria, Valparaiso (Chile); Cvetic, G [Department of Physics, Universidad Tecn. Federico Santa Maria, Valparaiso (Chile); Jeong, K S [Department of Physics, Korea Advanced Institute of Science and Technology, Daejon (Korea, Republic of); Lee, Taekoon [Department of Physics, Korea Advanced Institute of Science and Technology, Daejon (Korea, Republic of)

    2003-08-01

    We recapitulate the method which resums the truncated perturbation series of a physical observable in a way which takes into account the structure of the leading infrared renormalon. We apply the method to the Gross-Llewellyn Smith (GLS) sum rule. By confronting the obtained result with the experimentally extracted GLS value, we determine the value of the QCD coupling parameter, which turns out to agree with the present world average.

  7. Portugal and Spain entering the Common Market: Their industrial competitiveness revisited

    OpenAIRE

    Donges, Jürgen B.; Schatz, Klaus-Werner

    1985-01-01

    The purpose of this paper is to assess the overall position as well as the relative strength and weakness of the Iberian manufacturing industries within an enlarged Community. Earlier studies of the authors (Donges, Schatzf 1980; Donges et al., 1982) are up-dated and extended to cover the bilateral trade relations between Portugal and Spain. Following a recapitulation of the major trade patterns of the Iberian countries, we examine the nature of their specialization, both with regard to the E...

  8. Glycogen Storage Disease Type Ia in Canines: A Model for Human Metabolic and Genetic Liver Disease

    OpenAIRE

    Specht, Andrew; Fiske, Laurie; Erger, Kirsten; Cossette, Travis; Verstegen, John; Campbell-Thompson, Martha; Struck, Maggie B.; Lee, Young Mok; Chou, Janice Y.; Byrne, Barry J.; Correia, Catherine E.; Mah, Cathryn S.; Weinstein, David A.; Conlon, Thomas J.

    2011-01-01

    A canine model of Glycogen storage disease type Ia (GSDIa) is described. Affected dogs are homozygous for a previously described M121I mutation resulting in a deficiency of glucose-6-phosphatase-α. Metabolic, clinicopathologic, pathologic, and clinical manifestations of GSDIa observed in this model are described and compared to those observed in humans. The canine model shows more complete recapitulation of the clinical manifestations seen in humans including “lactic acidosis”, larger size,...

  9. Organoids as Models for Neoplastic Transformation | Office of Cancer Genomics

    Science.gov (United States)

    Cancer models strive to recapitulate the incredible diversity inherent in human tumors. A key challenge in accurate tumor modeling lies in capturing the panoply of homo- and heterotypic cellular interactions within the context of a three-dimensional tissue microenvironment. To address this challenge, researchers have developed organotypic cancer models (organoids) that combine the 3D architecture of in vivo tissues with the experimental facility of 2D cell lines.

  10. Searching for superconductors with high critical temperature

    Energy Technology Data Exchange (ETDEWEB)

    Chao, C

    1977-08-18

    Critical temperature of superconductors can be and must be raised so that their range of application can be broadened. It was estimated that, in 3 to 5 years, superconductor electric generators might be used in nuclear submarines and/or other applications where the requirements of small volume and light weight are critical. The BCS theory was recapitulated. Possible methods of achieving higher critical temperature were proposed and discussed.

  11. Variants in Nebulin (NEB) Are Linked to the Development of Familial Primary Angle Closure Glaucoma in Basset Hounds

    OpenAIRE

    Ahram, D.F.; Grozdanic, S.D.; Kecova, H.; Henkes, A.; Collin, R.W.J.; Kuehn, M.H.

    2015-01-01

    Several dog breeds are susceptible to developing primary angle closure glaucoma (PACG), which suggests a genetic basis for the disease. We have identified a four-generation Basset Hound pedigree with characteristic autosomal recessive PACG that closely recapitulates PACG in humans. Our aim is to utilize gene mapping and whole exome sequencing approaches to identify PACG-causing sequence variants in the Basset. Extensive clinical phenotyping of all pedigree members was conducted. SNP-chip geno...

  12. The paradox of Foxd3: how does it function in pluripotency and differentiation of embryonic stem cells?

    OpenAIRE

    Plank-Bazinet, Jennifer L.; Mundell, Nathan A.

    2016-01-01

    Uncommitted cells of the early mammalian embryo transition through distinct stages of pluripotency, including establishment of ground state “naïve” pluripotency in the early epiblast, transition to a post-implantation “primed” state, and subsequent lineage commitment of the gastrulating epiblast. Previous transcriptional profiling of in vitro models to recapitulate early to late epiblast transition and differentiation suggest that distinct gene regulatory networks are likely to function in ea...

  13. Biochemical and Pharmacological Characterizations of ESI-09 Based EPAC Inhibitors: Defining the ESI-09 “Therapeutic Window”

    OpenAIRE

    Yingmin Zhu; Haijun Chen; Stephen Boulton; Fang Mei; Na Ye; Giuseppe Melacini; Jia Zhou; Xiaodong Cheng

    2015-01-01

    The cAMP signaling cascade is one of the most frequently targeted pathways for the development of pharmaceutics. A plethora of recent genetic and pharmacological studies suggest that exchange proteins directly activated by cAMP (EPACs) are implicated in multiple pathologies. Selective EPAC inhibitors have been recently developed. One specific inhibitor, ESI-09, has been shown to block EPAC activity and functions, as well as to recapitulate genetic phenotypes of EPAC knockout mice when applied...

  14. Small molecule inhibition of cGAS reduces interferon expression in primary macrophages from autoimmune mice

    OpenAIRE

    Vincent, Jessica; Adura, Carolina; Gao, Pu; Luz, Antonio; Lama, Lodoe; Asano, Yasutomi; Okamoto, Rei; Imaeda, Toshihiro; Aida, Jumpei; Rothamel, Katherine; Gogakos, Tasos; Steinberg, Joshua; Reasoner, Seth; Aso, Kazuyoshi; Tuschl, Thomas

    2017-01-01

    Cyclic GMP-AMP synthase is essential for innate immunity against infection and cellular damage, serving as a sensor of DNA from pathogens or mislocalized self-DNA. Upon binding double-stranded DNA, cyclic GMP-AMP synthase synthesizes a cyclic dinucleotide that initiates an inflammatory cellular response. Mouse studies that recapitulate causative mutations in the autoimmune disease Aicardi-Goutières syndrome demonstrate that ablating the cyclic GMP-AMP synthase gene abolishes the deleterious p...

  15. Remodeling of retrotransposon elements during epigenetic induction of adult visual cortical plasticity by HDAC inhibitors

    DEFF Research Database (Denmark)

    Lennartsson, Andreas; Arner, Erik; Fagiolini, Michela

    2015-01-01

    BACKGROUND: The capacity for plasticity in the adult brain is limited by the anatomical traces laid down during early postnatal life. Removing certain molecular brakes, such as histone deacetylases (HDACs), has proven to be effective in recapitulating juvenile plasticity in the mature visual cortex...... and reactivate plasticity in the adult cortex. CONCLUSIONS: Treatment with HDAC inhibitors increases accessibility to enhancers and repetitive elements underlying brain-specific gene expression and reactivation of visual cortical plasticity....

  16. AOM/DSS Model of Colitis-Associated Cancer

    Science.gov (United States)

    Parang, Bobak; Barret, Caitlyn W.; Williams, Christopher S.

    2016-01-01

    Summary Our understanding of colitis-associated carcinoma (CAC) has benefited substantially from mouse models that faithfully recapitulate human CAC. Chemical models, in particular, have enabled fast and efficient analysis of genetic and environmental modulators of CAC without the added requirement of time-intensive genetic crossings. Here we describe the Azoxymethane (AOM)/Dextran Sodium Sulfate (DSS) mouse model of inflammatory colorectal cancer. PMID:27246042

  17. O vývojových tendencích v novočeském vyprávění. Několik poznámek // Several notes to the developmental tendencies in modern Czech narration

    Directory of Open Access Journals (Sweden)

    Jiří Koten

    2016-04-01

    Full Text Available The contribution summarizes and recapitulates issues of narrative historical poetics. It deepens knowledge of profile narrative texts (classic and modern and narrative modes (rhetorical, objective and subjective narration with respect to the developmental point of view. In conformity with Doležel’s requirement of the research on narrative transformations in so called longue durée (long duration the contribution observes the processes of subjectivisation and objectivisation of modern Czech narration.

  18. Antitumor effects of regorafenib and sorafenib in preclinical models of hepatocellular carcinoma

    OpenAIRE

    Kissel, Maria; Berndt, Sandra; Fiebig, Lukas; Kling, Simon; Ji, Qunsheng; Gu, Qingyang; Lang, Tina; Hafner, Frank-Thorsten; Teufel, Michael; Zopf, Dieter

    2017-01-01

    The purpose of this study was to investigate the antitumor activity of regorafenib and sorafenib in preclinical models of HCC and to assess their mechanism of action by associated changes in protein expression in a HCC-PDX mouse model. Both drugs were administered orally once daily at 10 mg/kg (regorafenib) or 30 mg/kg (sorafenib), which recapitulate the human exposure at the maximally tolerated dose in mice. In a H129 hepatoma model, survival times differed significantly between regorafenib ...

  19. Chance, destiny, and the inner workings of ClpXP.

    Science.gov (United States)

    Russell, Rick; Matouschek, Andreas

    2014-07-31

    AAA+ proteases are responsible for protein degradation in all branches of life. Using single-molecule and ensemble assays, Cordova et al. investigate how the bacterial protease ClpXP steps through a substrate's polypeptide chain and construct a quantitative kinetic model that recapitulates the interplay between stochastic and deterministic behaviors of ClpXP. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. A transgenic Alzheimer rat with plaques, tau pathology, behavioral impairment, oligomeric Aβ and frank neuronal loss

    OpenAIRE

    Cohen, Robert M.; Rezai-Zadeh, Kavon; Weitz, Tara M.; Rentsendorj, Altan; Gate, David; Spivak, Inna; Bholat, Yasmin; Vasilevko, Vitaly; Glabe, Charles G.; Breunig, Joshua J.; Rakic, Pasko; Davtyan, Hayk; Agadjanyan, Michael G.; Kepe, Vladimir; Barrio, Jorge

    2013-01-01

    Alzheimer’s disease (AD) is hallmarked by amyloid plaques, neurofibrillary tangles, and widespread cortical neuronal loss (Selkoe, 2001). The ‘amyloid cascade hypothesis’ posits that cerebral amyloid sets neurotoxic events into motion that precipitate Alzheimer dementia (Hardy and Allsop, 1991). Yet, faithful recapitulation of all AD features in widely used transgenic (Tg) mice engineered to overproduce Aβ peptides has been elusive. We have developed a Tg rat model (line TgF344-AD) expressing...

  1. A Markov chain model for N-linked protein glycosylation – towards a low-parameter tool for model-driven glycoengineering

    DEFF Research Database (Denmark)

    Spahn, Philipp N.; Hansen, Anders Holmgaard; Hansen, Henning Gram

    2016-01-01

    Glycosylation is a critical quality attribute of most recombinant biotherapeutics. Consequently, drug development requires careful control of glycoforms to meet bioactivity and biosafety requirements. However, glycoengineering can be extraordinarily difficult given the complex reaction networks...... present a novel low-parameter approach to describe glycosylation using flux-balance and Markov chain modeling. The model recapitulates the biological complexity of glycosylation, but does not require user-provided kinetic information. We use this method to predict and experimentally validate glycoprofiles...

  2. Many reasons or just one : How response mode affects reasoning in the conjunction problem

    OpenAIRE

    Hertwig, R.; Chase, V.

    1998-01-01

    Forty years of experimentation on class inclusion and its probabilistic relatives have led to inconsistent results and conclusions about human reasoning. Recent research on the conjunction "fallacy" recapitulates this history. In contrast to previous results, we found that a majority of participants adhere to class inclusion in the classic Linda problem. We outline a theoretical framework that attributes the contradictory results to differences in statistical sophistication and to differences...

  3. Experimentation of nuclear weapons, releases and storages of radioactive wastes in the Kara sea and in New Zemble

    International Nuclear Information System (INIS)

    Charmasson, S.

    1996-01-01

    132 nuclear weapons were tested from 1955 to 1990 in New Zemble. From 1959 to 1993, low level liquid radioactive wastes, low and medium level solid radioactive wastes, reactor core and fuel of submarine and nuclear propelled ships were released in the Kara and the Barentz seas. For these two seas, a recapitulation of the different radioactive sources and the found level of radioactivity of the marine environment are presented. (A.B.). 22 refs. 4 figs., 6 tabs

  4. Recuperation of the Roman circus in Tarragona

    Directory of Open Access Journals (Sweden)

    Ricardo Mar

    1998-12-01

    Full Text Available It is an ambitious operation in archaeology, architectural and urbanistic restoration suitable for an ensemble that deserves to be considered a World Heritage Site. There will still be a delicate architectural restoration task to be carried out once the current excavations have been completed, so that is a good time to recapitulate and present a summary of the methodology used till today, contribute from LOGGIA to its diffusion, and encourage great success for the future.

  5. Oxytocin signaling in the medial amygdala is required for sex discrimination of social cues

    OpenAIRE

    Yao, Shenqin; Bergan, Joseph; Lanjuin, Anne; Dulac, Catherine

    2017-01-01

    The neural control of social behaviors in rodents requires the encoding of pheromonal cues by the vomeronasal system. Here we show that the typical preference of male mice for females is eliminated in mutants lacking oxytocin, a neuropeptide modulating social behaviors in many species. Ablation of the oxytocin receptor in aromatase-expressing neurons of the medial amygdala (MeA) fully recapitulates the elimination of female preference in males. Further, single-unit recording in the MeA uncove...

  6. Oxytocin Signaling in the Medial Amygdala is required for Sex Discrimination of Social Cues

    OpenAIRE

    Bergan, Joseph; Yao, Shenqin; Lanjuin, Anne; Dulac, Catherine

    2017-01-01

    The neural control of social behaviors in rodents requires the encoding of pheromonal cues by the vomeronasal system. Here we show that the typical preference of male mice for females is eliminated in mutants lacking oxytocin, a neuropeptide modulating social behaviors in many species. Ablation of the oxytocin receptor in aromatase expressing neurons of the medial amygdala (MeA) fully recapitulates the elimination of female preference in males. Further, single unit recording in the MeA uncove...

  7. Automatic Exchange of Information as the new global standard: the end of (offshore tax evasion) history?

    OpenAIRE

    Meinzer, Markus

    2017-01-01

    Automatic exchange of information (AEoI) for tax purposes has become the global standard for international tax cooperation in 2013. As a tool for containing offshore tax evasion, it has encountered opposition in the past and continues to be fraught with challenges. This paper recapitulates the rationale for AEoI, including estimates on the magnitudes of assets held offshore, with a specific focus on Turkish assets held in Germany (chapter 1). Subsequently, chapter 2 summarises the recent hist...

  8. Sympatho-adrenal activation by chronic intermittent hypoxia

    OpenAIRE

    Prabhakar, Nanduri R.; Kumar, Ganesh K.; Peng, Ying-Jie

    2012-01-01

    Recurrent apnea with chronic intermittent hypoxia (CIH) is a major clinical problem in adult humans and infants born preterm. Patients with recurrent apnea exhibit heightened sympathetic activity as well as elevated plasma catecholamine levels, and these phenotypes are effectively recapitulated in rodent models of CIH. This article summarizes findings from studies addressing sympathetic activation in recurrent apnea patients and rodent models of CIH and the underlying cellular and molecular m...

  9. Insight on the energy in the United States

    International Nuclear Information System (INIS)

    Jamet, Ph.

    2006-11-01

    This document recapitulates the main characteristics and the key data of the energy in the United States (fossil energies, renewable energies, electric power production). The main american strategies are then described as the actions at the international scale during the last five years. The main data of the research programs in the energy domain are presented and the possible consequences of the government change at the Congress are analyzed. (A.L.B.)

  10. A Biochemical Screen for Identification of Small-Molecule Regulators of the Wnt Pathway Using Xenopus Egg Extracts

    OpenAIRE

    Thorne, Curtis A.; Lafleur, Bonnie; Lewis, Michelle; Hanson, Alison J.; Jernigan, Kristin K.; Weaver, David C.; Huppert, Kari A.; Chen, Tony W.; Wichadiit, Chonlarat; Cselenyi, Christopher S.; Tahinci, Emilios; Meyers, Kelly C.; Waskow, Emily; Orton, Darren; Salic, Adrian

    2011-01-01

    Misregulation of the Wnt pathway has been shown to be responsible for a variety of human diseases, most notably cancers. Screens for inhibitors of this pathway have been performed almost exclusively using cultured mammalian cells or with purified proteins. We have previously developed a biochemical assay using Xenopus egg extracts to recapitulate key cytoplasmic events in the Wnt pathway. Using this biochemical system, we show that a recombinant form of the Wnt coreceptor, LRP6, regulates the...

  11. Characterization and pathogenesis of aerosolized eastern equine encephalitis in the common marmoset (Callithrix jacchus)

    OpenAIRE

    Porter, Aimee I.; Erwin-Cohen, Rebecca A.; Twenhafel, Nancy; Chance, Taylor; Yee, Steven B.; Kern, Steven J.; Norwood, David; Hartman, Laurie J.; Parker, Michael D.; Glass, Pamela J.; DaSilva, Luis

    2017-01-01

    Background Licensed antiviral therapeutics and vaccines to protect against eastern equine encephalitis virus (EEEV) in humans currently do not exist. Animal models that faithfully recapitulate the clinical characteristics of human EEEV encephalitic disease, including fever, drowsiness, anorexia, and neurological signs such as seizures, are needed to satisfy requirements of the Food and Drug Administration (FDA) for clinical product licensing under the Animal Rule. Methods In an effort to meet...

  12. 3D-Printed ABS and PLA Scaffolds for Cartilage and Nucleus Pulposus Tissue Regeneration

    OpenAIRE

    Rosenzweig, Derek H.; Carelli, Eric; Steffen, Thomas; Jarzem, Peter; Haglund, Lisbet

    2015-01-01

    Painful degeneration of soft tissues accounts for high socioeconomic costs. Tissue engineering aims to provide biomimetics recapitulating native tissues. Biocompatible thermoplastics for 3D printing can generate high-resolution structures resembling tissue extracellular matrix. Large-pore 3D-printed acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) scaffolds were compared for cell ingrowth, viability, and tissue generation. Primary articular chondrocytes and nucleus pulposus (N...

  13. Insight on the energy in the United States; Apercus sur l'energie aux Etats-Unis

    Energy Technology Data Exchange (ETDEWEB)

    Jamet, Ph

    2006-11-15

    This document recapitulates the main characteristics and the key data of the energy in the United States (fossil energies, renewable energies, electric power production). The main american strategies are then described as the actions at the international scale during the last five years. The main data of the research programs in the energy domain are presented and the possible consequences of the government change at the Congress are analyzed. (A.L.B.)

  14. Microgel Mechanics in Biomaterial Design

    OpenAIRE

    Saxena, Shalini; Hansen, Caroline E.; Lyon, L. Andrew

    2014-01-01

    Conspectus The field of polymeric biomaterials has received much attention in recent years due to its potential for enhancing the biocompatibility of systems and devices applied to drug delivery and tissue engineering. Such applications continually push the definition of biocompatibility from relatively straightforward issues such as cytotoxicity to significantly more complex processes such as reducing foreign body responses or even promoting/recapitulating natural body functions. Hydrogels a...

  15. BMP4 density gradient in disk-shaped confinement

    Science.gov (United States)

    Bozorgui, Behnaz; Teimouri, Hamid; Kolomeisky, Anatoly B.

    We present a quantitative model that explains the scaling of BMP4 gradients during gastrulation and the recent experimental observation that geometric confinement of human embryonic stem cells is sufficient to recapitulate much of germ layer patterning. Based on a assumption that BMP4 diffusion rate is much smaller than the diffusion rate of it's inhibitor molecules, our results confirm that the length-scale which defines germ layer territories does not depend on system size.

  16. Voluntary sport and highway risks in adolescents and youths (following current French and Canadian periodical publications of 2000th

    Directory of Open Access Journals (Sweden)

    Rabinovich M.I.

    2013-06-01

    Full Text Available In this article we discuss some personal traits of adolescents and young people, disposed to different types of risky behavior. We describe correlations between different types of risky behavior in one individual. We discuss also the gender aspect of risk taking in adolescents and youth. Some modern theories of risk taking are recapitulated. Finally, we discuss the organizational question about the preventive work with adolescents and youth, aimed on minimization of sportive and highway risk.

  17. The Role of AR- and VDR-Modulated miRNAs in Sensitization of Prostate Cancer Cells to Therapy

    Science.gov (United States)

    2012-10-01

    13]. Thus, at the time of diagnosis of PCa, he majority of men have declining serum T and low D3 levels, eading to the hypothesis that the two...translatability of PPARA mRNA (Fig. 1), eading to increases in PPARA protein expression, which in turn romotes neutral lipid synthesis and energy storage. This is...surrounding lymph nodes from the primary tumors before establishing bone metastases. This linear temporal relationship is not recapitulated using other

  18. Modeling Human Nonalcoholic Steatohepatitis-Associated Changes in Drug Transporter Expression Using Experimental Rodent Models

    OpenAIRE

    Canet, Mark J.; Hardwick, Rhiannon N.; Lake, April D.; Dzierlenga, Anika L.; Clarke, John D.; Cherrington, Nathan J.

    2014-01-01

    Nonalcoholic fatty liver disease is a prevalent form of chronic liver disease that can progress to the more advanced stage of nonalcoholic steatohepatitis (NASH). NASH has been shown to alter drug transporter regulation and may have implications in the development of adverse drug reactions. Several experimental rodent models have been proposed for the study of NASH, but no single model fully recapitulates all aspects of the human disease. The purpose of the current study was to determine whic...

  19. Three-dimensional neural cultures produce networks that mimic native brain activity.

    Science.gov (United States)

    Bourke, Justin L; Quigley, Anita F; Duchi, Serena; O'Connell, Cathal D; Crook, Jeremy M; Wallace, Gordon G; Cook, Mark J; Kapsa, Robert M I

    2018-02-01

    Development of brain function is critically dependent on neuronal networks organized through three dimensions. Culture of central nervous system neurons has traditionally been limited to two dimensions, restricting growth patterns and network formation to a single plane. Here, with the use of multichannel extracellular microelectrode arrays, we demonstrate that neurons cultured in a true three-dimensional environment recapitulate native neuronal network formation and produce functional outcomes more akin to in vivo neuronal network activity. Copyright © 2017 John Wiley & Sons, Ltd.

  20. Stress Effects on Multiple Memory System Interactions

    OpenAIRE

    Ness, Deborah; Calabrese, Pasquale

    2016-01-01

    Extensive behavioural, pharmacological, and neurological research reports stress effects on mammalian memory processes. While stress effects on memory quantity have been known for decades, the influence of stress on multiple memory systems and their distinct contributions to the learning process have only recently been described. In this paper, after summarizing the fundamental biological aspects of stress/emotional arousal and recapitulating functionally and anatomically distinct memory syst...

  1. A Cicerone for the Physics of Charm

    OpenAIRE

    Bianco, S.; Fabbri, F. L.; Benson, D.; Bigi, I.

    2003-01-01

    After briefly recapitulating the history of the charm quantum number we sketch the experimental environments and instruments employed to study the behaviour of charm hadrons and then describe the theoretical tools for treating charm dynamics. We discuss a wide range of inclusive production processes before analyzing the spectroscopy of hadrons with hidden and open charm and the weak lifetimes of charm mesons and baryons. Then we address leptonic, exclusive semileptonic and nonleptonic charm d...

  2. [Chakrabarty today: 30 years after the United States Supreme Court Resolution].

    Science.gov (United States)

    Bergel, Salvador Darío

    2010-01-01

    The decision of the United States Supreme Court in the Chakrabarty case marked the beginning of a far reaching process, the development of which considerably extended the field of patentabiltiy of humans, their body parts and genetic information. The author believes that a period of three decades is sufficient to draw conclusions. A critical point has been reached from a debatable decision, which had more economic support than legal, which requires serious recapitulation of the scope and the purpose of industrial property rights.

  3. Regenerative Endodontics: Barriers and Strategies for Clinical Translation

    OpenAIRE

    Kim, Sahng G.; Zhou, Jian; Ye, Ling; Cho, Shoko; Suzuki, Takahiro; Fu, Susan Y.; Yang, Rujing; Zhou, Xuedong; Mao, Jeremy J.

    2012-01-01

    Despite a great deal of enthusiasm and effort, regenerative endodontics has encountered substantial challenges towards clinical translation. Recent adoption by the American Dental Association (ADA) of evoked pulp bleeding in immature permanent teeth is an important step for regenerative endodontics. However, there is no regenerative therapy for the majority of endodontic diseases. Simple recapitulation of cell therapy and tissue engineering strategies that are under development for other orga...

  4. Subverting the Dominant Order: Narrative as Weapon in Simone de Beauvoir's Tous les hommes sont mortels

    OpenAIRE

    Barbara Klaw

    1996-01-01

    This essay argues that through the narrative techniques of point of view and embedding, Beauvoir carefully constructed her narrative and those of her male and female characters in Tous les hommes sont mortels , her third novel, published in 1946, in order to explain why males dominate society and to encourage women to fight against the current patriarchal social order. Many critics view Fosca as the principal character, and his 400-page embedded recapitulation of his past as the predominant ...

  5. 3D culture models of Alzheimer's disease: a road map to a "cure-in-a-dish".

    Science.gov (United States)

    Choi, Se Hoon; Kim, Young Hye; Quinti, Luisa; Tanzi, Rudolph E; Kim, Doo Yeon

    2016-12-09

    Alzheimer's disease (AD) transgenic mice have been used as a standard AD model for basic mechanistic studies and drug discovery. These mouse models showed symbolic AD pathologies including β-amyloid (Aβ) plaques, gliosis and memory deficits but failed to fully recapitulate AD pathogenic cascades including robust phospho tau (p-tau) accumulation, clear neurofibrillary tangles (NFTs) and neurodegeneration, solely driven by familial AD (FAD) mutation(s). Recent advances in human stem cell and three-dimensional (3D) culture technologies made it possible to generate novel 3D neural cell culture models that recapitulate AD pathologies including robust Aβ deposition and Aβ-driven NFT-like tau pathology. These new 3D human cell culture models of AD hold a promise for a novel platform that can be used for mechanism studies in human brain-like environment and high-throughput drug screening (HTS). In this review, we will summarize the current progress in recapitulating AD pathogenic cascades in human neural cell culture models using AD patient-derived induced pluripotent stem cells (iPSCs) or genetically modified human stem cell lines. We will also explain how new 3D culture technologies were applied to accelerate Aβ and p-tau pathologies in human neural cell cultures, as compared the standard two-dimensional (2D) culture conditions. Finally, we will discuss a potential impact of the human 3D human neural cell culture models on the AD drug-development process. These revolutionary 3D culture models of AD will contribute to accelerate the discovery of novel AD drugs.

  6. Fischer-344 Tp53-knockout rats exhibit a high rate of bone and brain neoplasia with frequent metastasis

    Directory of Open Access Journals (Sweden)

    Sarah A. Hansen

    2016-10-01

    Full Text Available Somatic mutations in the Tp53 tumor suppressor gene are the most commonly seen genetic alterations in cancer, and germline mutations in Tp53 predispose individuals to a variety of early-onset cancers. Development of appropriate translational animal models that carry mutations in Tp53 and recapitulate human disease are important for drug discovery, biomarker development and disease modeling. Current Tp53 mouse and rat models have significant phenotypic and genetic limitations, and often do not recapitulate certain aspects of human disease. We used a marker-assisted speed congenic approach to transfer a well-characterized Tp53-mutant allele from an outbred rat to the genetically inbred Fischer-344 (F344 rat to create the F344-Tp53tm1(EGFP-PacQly/Rrrc (F344-Tp53 strain. On the F344 genetic background, the tumor spectrum shifted, with the primary tumor types being osteosarcomas and meningeal sarcomas, compared to the hepatic hemangiosarcoma and lymphoma identified in the original outbred stock model. The Fischer model is more consistent with the early onset of bone and central nervous system sarcomas found in humans with germline Tp53 mutations. The frequency of osteosarcomas in F344-Tp53 homozygous and heterozygous animals was 57% and 36%, respectively. Tumors were highly representative of human disease radiographically and histologically, with tumors found primarily on long bones with frequent pulmonary metastases. Importantly, the rapid onset of osteosarcomas in this promising new model fills a current void in animal models that recapitulate human pediatric osteosarcomas and could facilitate studies to identify therapeutic targets.

  7. Sliding contact loading enhances the tensile properties of mesenchymal stem cell-seeded hydrogels

    Directory of Open Access Journals (Sweden)

    AH Huang

    2012-07-01

    Full Text Available The primary goal of cartilage tissue engineering is to recapitulate the functional properties and structural features of native articular cartilage. While there has been some success in generating near-native compressive properties, the tensile properties of cell-seeded constructs remain poor, and key features of cartilage, including inhomogeneity and anisotropy, are generally absent in these engineered constructs. Therefore, in an attempt to instill these hallmark properties of cartilage in engineered cell-seeded constructs, we designed and characterized a novel sliding contact bioreactor to recapitulate the mechanical stimuli arising from physiologic joint loading (two contacting cartilage layers. Finite element modeling of this bioreactor system showed that tensile strains were direction-dependent, while both tensile strains and fluid motion were depth-dependent and highest in the region closest to the contact surface. Short-term sliding contact of mesenchymal stem cell (MSC-seeded agarose improved chondrogenic gene expression in a manner dependent on both the axial strain applied and transforming growth factor-β supplementation. Using the optimized loading parameters derived from these short-term studies, long-term sliding contact was applied to MSC-seeded agarose constructs for 21 d. After 21 d, sliding contact significantly improved the tensile properties of MSC-seeded constructs and elicited alterations in type II collagen and proteoglycan accumulation as a function of depth; staining for these matrix molecules showed intense localization in the surface regions. These findings point to the potential of sliding contact to produce engineered cartilage constructs that begin to recapitulate the complex mechanical features of the native tissue.

  8. Functional properties of hepatocytes in vitro are correlated with cell polarity maintenance.

    Science.gov (United States)

    Zeigerer, Anja; Wuttke, Anne; Marsico, Giovanni; Seifert, Sarah; Kalaidzidis, Yannis; Zerial, Marino

    2017-01-01

    Exploring the cell biology of hepatocytes in vitro could be a powerful strategy to dissect the molecular mechanisms underlying the structure and function of the liver in vivo. However, this approach relies on appropriate in vitro cell culture systems that can recapitulate the cell biological and metabolic features of the hepatocytes in the liver whilst being accessible to experimental manipulations. Here, we adapted protocols for high-resolution fluorescence microscopy and quantitative image analysis to compare two primary hepatocyte culture systems, monolayer and collagen sandwich, with respect to the distribution of two distinct populations of early endosomes (APPL1 and EEA1-positive), endocytic capacity, metabolic and signaling activities. In addition to the re-acquisition of hepatocellular polarity, primary hepatocytes grown in collagen sandwich but not in monolayer culture recapitulated the apico-basal distribution of EEA1 endosomes observed in liver tissue. We found that such distribution correlated with the organization of the actin cytoskeleton in vitro and, surprisingly, was dependent on the nutritional state in vivo. Hepatocytes in collagen sandwich also exhibited faster kinetics of low-density lipoprotein (LDL) and epidermal growth factor (EGF) internalization, showed improved insulin sensitivity and preserved their ability for glucose production, compared to hepatocytes in monolayer cultures. Although no in vitro culture system can reproduce the exquisite structural features of liver tissue, our data nevertheless highlight the ability of the collagen sandwich system to recapitulate key structural and functional properties of the hepatocytes in the liver and, therefore, support the usage of this system to study aspects of hepatocellular biology in vitro. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Brief Communication: Tissue-engineered Microenvironment Systems for Modeling Human Vasculature

    Science.gov (United States)

    Tourovskaia, Anna; Fauver, Mark; Kramer, Gregory; Simonson, Sara; Neumann, Thomas

    2015-01-01

    The high attrition rate of drug candidates late in the development process has led to an increasing demand for test assays that predict clinical outcome better than conventional 2D cell culture systems and animal models. Government agencies, the military, and the pharmaceutical industry have started initiatives for the development of novel in-vitro systems that recapitulate functional units of human tissues and organs. There is growing evidence that 3D cell arrangement, co-culture of different cell types, and physico-chemical cues lead to improved predictive power. A key element of all tissue microenvironments is the vasculature. Beyond transporting blood the microvasculature assumes important organ-specific functions. It is also involved in pathologic conditions, such as inflammation, tumor growth, metastasis, and degenerative diseases. To provide a tool for modeling this important feature of human tissue microenvironments, we developed a microfluidic chip for creating tissue-engineered microenvironment systems (TEMS) composed of tubular cell structures. Our chip design encompasses a small chamber that is filled with an extracellular matrix (ECM) surrounding one or more tubular channels. Endothelial cells seeded into the channels adhere to the ECM walls and grow into perfusable tubular tissue structures that are fluidically connected to upstream and downstream fluid channels in the chip. Using these chips we created models of angiogenesis, the blood-brain-barrier (BBB), and tumor-cell extravasation. Our angiogenesis model recapitulates true angiogenesis, in which sprouting occurs from a “parent” vessel in response to a gradient of growth factors. Our BBB model is composed of a microvessel generated from brain-specific endothelial cells (ECs) within an ECM populated with astrocytes and pericytes. Our tumor-cell extravasation model can be utilized to visualize and measure tumor-cell migration through vessel walls into the surrounding matrix. The described

  10. Metallurgy of continuous filamentary A15 superconductors

    International Nuclear Information System (INIS)

    Suenaga, M.

    1980-01-01

    The early history of the bronze process is recapitulated and modifications to the process which have since followed are described. The metallurgical principles, which are involved in the process, are described including the kinetics of the compound growth, the effects of additives on the growth, etc. The superconducting properties of these compounds are also discussed. The influence of metallurgical variables on the superconducting properties is discussed in detail. In discussing the superconducting current densities in these compounds, limits in applicability of existing magnetic-flux-pinning models are also treated as well as methods for determining critical magnetic fields

  11. A geologic guide to Wrangell-Saint Elias National Park and Preserve, Alaska; a tectonic collage of northbound terranes

    Science.gov (United States)

    Winkler, Gary R.; with contributions by MacKevett, E. M.; Plafker, George; Richter, D.H.; Rosenkrans, D.S.; Schmoll, H.R.

    2000-01-01

    Wrangell-Saint Elias National Park and Preserve, the largest unit in the U.S. National Park System, encompasses near 13.2 million acres of geological wonderments. This geologic guide presents history of exploration and Earth-science investigation; describes the complex geologic makeup; characterizes the vast college of accretion geologic terranes in this area of Alaska's continental margin; recapitulates the effects of earthquakes, volcanoes, and glaciers; characterizes the copper and gold resources of the parklands; and describes outstanding locales within the park and preserve area. A glossary of geologic terms and a categorized list of additional sources of information complete this report.

  12. Non-conventional Energy Sources and Energy Development Strategy of Croatia

    International Nuclear Information System (INIS)

    Kalea, M.

    2006-01-01

    The distinction between unconventional renewable energy resources is elaborated. Further, general and specific properties of unconventional energy resources are concisely recapitulated; also comparison is made to conventional energy resources. Exact data are brought forth, investment and operative costs are discussed which illustrate some properties of unconventional energy resources. Overview of obligations of different countries is given as well, which derive from the EC directive on renewable energy resources. At the end, a critical view on renewable energy resources in the Strategy of energy development of Croatia is given.(author)

  13. Ground rules of the pluripotency gene regulatory network.

    KAUST Repository

    Li, Mo

    2017-01-03

    Pluripotency is a state that exists transiently in the early embryo and, remarkably, can be recapitulated in vitro by deriving embryonic stem cells or by reprogramming somatic cells to become induced pluripotent stem cells. The state of pluripotency, which is stabilized by an interconnected network of pluripotency-associated genes, integrates external signals and exerts control over the decision between self-renewal and differentiation at the transcriptional, post-transcriptional and epigenetic levels. Recent evidence of alternative pluripotency states indicates the regulatory flexibility of this network. Insights into the underlying principles of the pluripotency network may provide unprecedented opportunities for studying development and for regenerative medicine.

  14. The Unicellular State as a Point Source in a Quantum Biological System

    Directory of Open Access Journals (Sweden)

    John S. Torday

    2016-05-01

    Full Text Available A point source is the central and most important point or place for any group of cohering phenomena. Evolutionary development presumes that biological processes are sequentially linked, but neither directed from, nor centralized within, any specific biologic structure or stage. However, such an epigenomic entity exists and its transforming effects can be understood through the obligatory recapitulation of all eukaryotic lifeforms through a zygotic unicellular phase. This requisite biological conjunction can now be properly assessed as the focal point of reconciliation between biology and quantum phenomena, illustrated by deconvoluting complex physiologic traits back to their unicellular origins.

  15. Reenacting the birth of an intron

    Energy Technology Data Exchange (ETDEWEB)

    Hellsten, Uffe; Aspden, Julie L.; Rio, Donald C.; Rokhsar, Daniel S.

    2011-07-01

    An intron is an extended genomic feature whose function requires multiple constrained positions - donor and acceptor splice sites, a branch point, a polypyrimidine tract and suitable splicing enhancers - that may be distributed over hundreds or thousands of nucleotides. New introns are therefore unlikely to emerge by incremental accumulation of functional sub-elements. Here we demonstrate that a functional intron can be created de novo in a single step by a segmental genomic duplication. This experiment recapitulates in vivo the birth of an intron that arose in the ancestral jawed vertebrate lineage nearly half a billion years ago.

  16. Dynamic microenvironments: the fourth dimension.

    Science.gov (United States)

    Tibbitt, Mark W; Anseth, Kristi S

    2012-11-14

    The extracellular space, or cell microenvironment, choreographs cell behavior through myriad controlled signals, and aberrant cues can result in dysfunction and disease. For functional studies of human cell biology or expansion and delivery of cells for therapeutic purposes, scientists must decipher this intricate map of microenvironment biology and develop ways to mimic these functions in vitro. In this Perspective, we describe technologies for four-dimensional (4D) biology: cell-laden matrices engineered to recapitulate tissue and organ function in 3D space and over time.

  17. Laurel Lodge Nursing Home, Templemichael Glebe, Longford.

    LENUS (Irish Health Repository)

    Mitchell, Kevin

    2011-11-11

    Abstract The number of individual cases of psychiatric disorders that can be ascribed to identified, rare, single mutations is increasing with great rapidity. Such mutations can be recapitulated in mice to generate animal models with direct etiological validity. Defining the underlying pathogenic mechanisms will require an experimental and theoretical framework to make the links from mutation to altered behavior in an animal or psychopathology in a human. Here, we discuss key elements of such a framework, including cell type-based phenotyping, developmental trajectories, linking circuit properties at micro and macro scales and definition of neurobiological phenotypes that are directly translatable to humans.

  18. EGFR gene overexpression retained in an invasive xenograft model by solid orthotopic transplantation of human glioblastoma multiforme into nude mice.

    Science.gov (United States)

    Yi, Diao; Hua, Tian Xin; Lin, Huang Yan

    2011-03-01

    Orthotopic xenograft animal model from human glioblastoma multiforme (GBM) cell lines often do not recapitulate an extremely important aspect of invasive growth and epidermal growth factor receptor (EGFR) gene overexpression of human GBM. We developed an orthotopic xenograft model by solid transplantation of human GBM into the brain of nude mouse. The orthotopic xenografts sharing the same histopathological features with their original human GBMs were highly invasive and retained the overexpression of EGFR gene. The murine orthotopic GBM models constitute a valuable in vivo system for preclinical studies to test novel therapies for human GBM.

  19. Orthotopic Patient-Derived Glioblastoma Xenografts in Mice.

    Science.gov (United States)

    Xu, Zhongye; Kader, Michael; Sen, Rajeev; Placantonakis, Dimitris G

    2018-01-01

    Patient-derived xenografts (PDX) provide in vivo glioblastoma (GBM) models that recapitulate actual tumors. Orthotopic tumor xenografts within the mouse brain are obtained by injection of GBM stem-like cells derived from fresh surgical specimens. These xenografts reproduce GBM's histologic complexity and hallmark biological behaviors, such as brain invasion, angiogenesis, and resistance to therapy. This method has become essential for analyzing mechanisms of tumorigenesis and testing the therapeutic effect of candidate agents in the preclinical setting. Here, we describe a protocol for establishing orthotopic tumor xenografts in the mouse brain with human GBM cells.

  20. The development of the breeder reactor program of the German Federal Republic

    International Nuclear Information System (INIS)

    Haunschild, H.H.

    1984-01-01

    This article recapitulates the stages of the program which is in hand in the German Federal Republic concerning breeder reactors with fast neutrons. In particular, it describes in detail the causes for the delays in the construction of the demonstration reactor SRN 300 (Kalkar) for which the commissioning has now been fixed for 1987. It emphasizes the importance of the collaboration which exists in Europe for the establishment of the projects and the construction of fast neutron power stations, including the SNR 2 reactor; the construction of the latter could begin in the German Federal Republic at the end of the Eighties [fr

  1. 3D Hanging Drop Culture to Establish Prostate Cancer Organoids.

    Science.gov (United States)

    Eder, Theresa; Eder, Iris E

    2017-01-01

    Three-dimensional (3D) cell culture enables the growth of cells in a multidimensional and multicellular manner compared to conventional cell culture techniques. Especially in prostate cancer research there is a big need for more tissue-recapitulating models to get a better understanding of the mechanisms driving prostate cancer as well as to screen for more efficient drugs that can be used for treatment. In this chapter we describe a 3D hanging drop system that can be used to culture prostate cancer organoids as tumor epithelial monocultures and as epithelial-stromal cocultures.

  2. Formal language theory: refining the Chomsky hierarchy.

    Science.gov (United States)

    Jäger, Gerhard; Rogers, James

    2012-07-19

    The first part of this article gives a brief overview of the four levels of the Chomsky hierarchy, with a special emphasis on context-free and regular languages. It then recapitulates the arguments why neither regular nor context-free grammar is sufficiently expressive to capture all phenomena in the natural language syntax. In the second part, two refinements of the Chomsky hierarchy are reviewed, which are both relevant to the extant research in cognitive science: the mildly context-sensitive languages (which are located between context-free and context-sensitive languages), and the sub-regular hierarchy (which distinguishes several levels of complexity within the class of regular languages).

  3. Hepcidin- A Burgeoning Biomarker

    Directory of Open Access Journals (Sweden)

    Hemkant Manikrao Deshmukh

    2017-10-01

    Full Text Available The discovery of hepcidin has triggered a virtual ignition of studies on iron metabolism and related disorders. The peptide hormone hepcidin is a key homeostatic regulator of iron metabolism. The synthesis of hepcidin is induced by systemic iron levels and by inflammatory stimuli. Several human diseases are associated with variations in hepcidin concentrations. The evaluation of hepcidin in biological fluids is therefore a promising device in the diagnosis and management of medical situations in which iron metabolism is affected. Thus, it made us to recapitulate role of hepcidin as biomarker.

  4. Energy, metals and ores in France in 1983

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    Every year the Annales des Mines devote one issue to the activities of the power producing and mineral industries. This issue refers to the year 1983, with a recapitulation of previous years. A first part describes the activity of the following principal sectors. Energy: solid mineral fuel, hydrocarbons, gas, electricity, uranium, geothermal power. Ores and metals: aluminium, antimony, silver, chromium, copper, tin, iron, manganese, nickel, gold, lead, tungsten, zinc. Nonmetallic substances: barite, phosphate, potash, salt, sulphur, fluorspar. The elements concern mainly France but they are presented in a world-wide context. A second part gives statistical items, completed and illustrated by diagrams [fr

  5. Energy, metals and ores in France in 1982

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    Every year the Annales des Mines devote one issue to the activities of the power producing and mineral industries. This issue refers to the year 1982, with a recapitulation of previous years. A first part describes the activity of the following principal sectors. Energy: solid mineral fuel, hydrocarbons, gas, electricity, uranium, geothermal power. Ores and metals: aluminium, antimony, silver, chromium, copper, tin, iron, manganese, nickel, gold, lead, tungsten, zinc. Nonmetallic substances: barite, phosphate, potash, salt, sulphur, fluorspar. The elements concern mainly France but they are presented in a world-wide context. A second part gives statistical items, completed and illustrated by diagrams [fr

  6. Human Embryonic Stem Cells: A Model for the Study of Neural Development and Neurological Diseases

    Directory of Open Access Journals (Sweden)

    Piya Prajumwongs

    2016-01-01

    Full Text Available Although the mechanism of neurogenesis has been well documented in other organisms, there might be fundamental differences between human and those species referring to species-specific context. Based on principles learned from other systems, it is found that the signaling pathways required for neural induction and specification of human embryonic stem cells (hESCs recapitulated those in the early embryo development in vivo at certain degree. This underscores the usefulness of hESCs in understanding early human neural development and reinforces the need to integrate the principles of developmental biology and hESC biology for an efficient neural differentiation.

  7. Packaging signals in single-stranded RNA viruses: nature?s alternative to a purely electrostatic assembly mechanism

    OpenAIRE

    Stockley, Peter G.; Twarock, Reidun; Bakker, Saskia E.; Barker, Amy M.; Borodavka, Alexander; Dykeman, Eric; Ford, Robert J.; Pearson, Arwen R.; Phillips, Simon E. V.; Ranson, Neil A.; Tuma, Roman

    2013-01-01

    The formation of a protective protein container is an essential step in the life-cycle of most viruses. In the case of single-stranded (ss)RNA viruses, this step occurs in parallel with genome packaging in a co-assembly process. Previously, it had been thought that this process can be explained entirely by electrostatics. Inspired by recent single-molecule fluorescence experiments that recapitulate the RNA packaging specificity seen in vivo for two model viruses, we present an alternative the...

  8. Creating biomaterials with spatially organized functionality.

    Science.gov (United States)

    Chow, Lesley W; Fischer, Jacob F

    2016-05-01

    Biomaterials for tissue engineering provide scaffolds to support cells and guide tissue regeneration. Despite significant advances in biomaterials design and fabrication techniques, engineered tissue constructs remain functionally inferior to native tissues. This is largely due to the inability to recreate the complex and dynamic hierarchical organization of the extracellular matrix components, which is intimately linked to a tissue's biological function. This review discusses current state-of-the-art strategies to control the spatial presentation of physical and biochemical cues within a biomaterial to recapitulate native tissue organization and function. © 2016 by the Society for Experimental Biology and Medicine.

  9. Text-analytic Measurement of Effectuation and Causation Orientations among Small and Global Business Managers

    DEFF Research Database (Denmark)

    Mattsson, Jan; Helmersson, Helge

    2012-01-01

    We demonstrate how one can measure overall quality in texts gathered from interviews by means of PERTEX text analytic method. We compare text analytic measures and content for locally active Scandinavian small business managers and globally operating Indian IT managers when recapitulating......-components we are also able to display the degree of fragmentation, focus and integration in the text. We show how AFFI measures differ between managers with a causation or effectuation orientation irrespective of their role as small business manager or as an established global manager. Hence, we posit...... that effectuation and causation orientations may be generic characteristic of managers in general....

  10. Sun, weather, and climate

    International Nuclear Information System (INIS)

    Herman, J.R.; Goldberg, R.A.

    1985-01-01

    The general field of sun-weather/climate relationships that is, apparent weather and climate responses to solar activity is introduced and theoretical and experimental suggestions for further research to identify and investigate the unknown casual mechanisms are provided. Topics of discussion include: (1) solar-related correlation factors and energy sources; (2) long-term climate trends; (3) short-term meteorological correlations; (4) miscellaneous obscuring influences; (5) physical processes and mechanisms; (6) recapitulation of sun-weather relationships; and (7) guidelines for experiments. 300 references

  11. SDCCAG8 interacts with rab effector proteins rabep2 and erc1 and is required for hedgehog signaling

    DEFF Research Database (Denmark)

    Airik, Rannar; Schueler, M.; Airik, M.

    2016-01-01

    Recessive mutations in the SDCCAG8 gene cause a nephronophthisis-related ciliopathy with Bardet-Biedl syndrome-like features in humans. Our previous characterization of the orthologous Sdccag8gt/gt mouse model recapitulated the retinal-renal disease phenotypes and identified impaired DNA damage......1), and with non-muscle myosin motor proteins (MYH9, MYH10, MYH14) at the centrosome. Furthermore, we show that RABEP2 localization at the centrosome is regulated by SDCCAG8. siRNA mediated RABEP2 knockdown in hTERT-RPE1 cells leads to defective ciliogenesis, indicating a critical role for RABEP2...

  12. Bioreactor engineering of stem cell environments.

    Science.gov (United States)

    Tandon, Nina; Marolt, Darja; Cimetta, Elisa; Vunjak-Novakovic, Gordana

    2013-11-15

    Stem cells hold promise to revolutionize modern medicine by the development of new therapies, disease models and drug screening systems. Standard cell culture systems have limited biological relevance because they do not recapitulate the complex 3-dimensional interactions and biophysical cues that characterize the in vivo environment. In this review, we discuss the current advances in engineering stem cell environments using novel biomaterials and bioreactor technologies. We also reflect on the challenges the field is currently facing with regard to the translation of stem cell based therapies into the clinic. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Generation of BAC transgenic epithelial organoids.

    Directory of Open Access Journals (Sweden)

    Gerald Schwank

    Full Text Available Under previously developed culture conditions, mouse and human intestinal epithelia can be cultured and expanded over long periods. These so-called organoids recapitulate the three-dimensional architecture of the gut epithelium, and consist of all major intestinal cell types. One key advantage of these ex vivo cultures is their accessibility to live imaging. So far the establishment of transgenic fluorescent reporter organoids has required the generation of transgenic mice, a laborious and time-consuming process, which cannot be extended to human cultures. Here we present a transfection protocol that enables the generation of recombinant mouse and human reporter organoids using BAC (bacterial artificial chromosome technology.

  14. DNA fingerprinting in forensics: past, present, future.

    Science.gov (United States)

    Roewer, Lutz

    2013-11-18

    DNA fingerprinting, one of the great discoveries of the late 20th century, has revolutionized forensic investigations. This review briefly recapitulates 30 years of progress in forensic DNA analysis which helps to convict criminals, exonerate the wrongly accused, and identify victims of crime, disasters, and war. Current standard methods based on short tandem repeats (STRs) as well as lineage markers (Y chromosome, mitochondrial DNA) are covered and applications are illustrated by casework examples. Benefits and risks of expanding forensic DNA databases are discussed and we ask what the future holds for forensic DNA fingerprinting.

  15. TeV. The dream energy scale

    International Nuclear Information System (INIS)

    Murayama, Hitoshi

    2006-01-01

    In this talk, I'd like to explain why the TeV, 1,000,000,000,00 electron volt, is a particularly interesting energy scale in physics. I being recapitulating what particle physics is all about, citing two big questions: what the Universe is made of, and Einstein's dream of unification. TeV energy appears to be relevant to both questions, suggesting rich and complex physics at this energy. I outline how two facilities, LHC and ILC, will work together with reveal what is going on at this exciting energy scale. (author)

  16. Building a better model of cancer

    Directory of Open Access Journals (Sweden)

    DeGregori James

    2006-10-01

    Full Text Available Abstract The 2006 Cold Spring Harbor Laboratory meeting on the Mechanisms and Models of Cancer was held August 16–20. The meeting featured several hundred presentations of many short talks (mostly selected from the abstracts and posters, with the airing of a number of exciting new discoveries. We will focus this meeting review on models of cancer (primarily mouse models, highlighting recent advances in new mouse models that better recapitulate sporadic tumorigenesis, demonstrations of tumor addiction to tumor suppressor inactivation, new insight into senescence as a tumor barrier, improved understanding of the evolutionary paths of cancer development, and environmental/immunological influences on cancer.

  17. Identification and Characterization of Linezolid-Resistant cfr-Positive Staphylococcus aureus USA300 Isolates from a New York City Medical Center

    Science.gov (United States)

    Zuill, Douglas E.; Scharn, Caitlyn R.; Deane, Jennifer; Sahm, Daniel F.; Goering, Richard V.; Jenkins, Stephen G.; Shaw, Karen J.

    2014-01-01

    The cfr gene was identified in three linezolid-resistant USA300 methicillin-resistant Staphylococcus aureus (MRSA) isolates collected over a 3-day period at a New York City medical center in 2011 as part of a routine surveillance program. Each isolate possessed a plasmid containing a pSCFS3-like cfr gene environment. Transformation of the cfr-bearing plasmids into the S. aureus ATCC 29213 background recapitulated the expected Cfr antibiogram, including resistance to linezolid, tiamulin, clindamycin, and florfenicol and susceptibility to tedizolid. PMID:25136008

  18. Peabody's "Care of the Patient" and the Nature of Medical Science.

    Science.gov (United States)

    Brody, Howard

    2014-01-01

    Francis W. Peabody's 1927 essay "The Care of the Patient" is widely quoted, yet few appreciate the subtlety of its interweaving of medical science with its more obvious humanistic elements. Understanding the essay in context requires a recapitulation of Peabody's life story, a review of earlier work that led up to the culminating lecture in 1926, and a detailed analysis of the thread of argument Peabody wove through the lecture. A better understanding of the essay shows how Peabody anticipated several important later developments in medical thought.

  19. Bioprinting is changing regenerative medicine forever.

    Science.gov (United States)

    Collins, Scott Forrest

    2014-12-01

    3D printing, or solid freeform fabrication, applied to regenerative medicine brings technologies from several industries together to help solve unique challenges in both basic science and tissue engineering. By more finely organizing cells and supporting structures precisely in 3D space, we will gain critical knowledge of cell-cell communications and cell-environment interactions. As we increase the scale, we will move toward complex tissue and organ structures where several cell phenotypes will functionally and structurally interact, thus recapitulating the form and function of native tissues and organs.

  20. Regenerative endodontics: barriers and strategies for clinical translation.

    Science.gov (United States)

    Mao, Jeremy J; Kim, Sahng G; Zhou, Jian; Ye, Ling; Cho, Shoko; Suzuki, Takahiro; Fu, Susan Y; Yang, Rujing; Zhou, Xuedong

    2012-07-01

    Regenerative endodontics has encountered substantial challenges toward clinical translation. The adoption by the American Dental Association of evoked pulp bleeding in immature permanent teeth is an important step for regenerative endodontics. However, there is no regenerative therapy for most endodontic diseases. Simple recapitulation of cell therapy and tissue engineering strategies that are under development for other organ systems has not led to clinical translation in regeneration endodontics. Recent work using novel biomaterial scaffolds and growth factors that orchestrate the homing of host endogenous cells represents a departure from traditional cell transplantation approaches and may accelerate clinical translation. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Following the genes: a framework for animal modeling of psychiatric disorders

    Directory of Open Access Journals (Sweden)

    Sawa Akira

    2011-11-01

    Full Text Available Abstract The number of individual cases of psychiatric disorders that can be ascribed to identified, rare, single mutations is increasing with great rapidity. Such mutations can be recapitulated in mice to generate animal models with direct etiological validity. Defining the underlying pathogenic mechanisms will require an experimental and theoretical framework to make the links from mutation to altered behavior in an animal or psychopathology in a human. Here, we discuss key elements of such a framework, including cell type-based phenotyping, developmental trajectories, linking circuit properties at micro and macro scales and definition of neurobiological phenotypes that are directly translatable to humans.

  2. Following the genes: a framework for animal modeling of psychiatric disorders

    LENUS (Irish Health Repository)

    Mitchell, Kevin

    2011-11-11

    Abstract The number of individual cases of psychiatric disorders that can be ascribed to identified, rare, single mutations is increasing with great rapidity. Such mutations can be recapitulated in mice to generate animal models with direct etiological validity. Defining the underlying pathogenic mechanisms will require an experimental and theoretical framework to make the links from mutation to altered behavior in an animal or psychopathology in a human. Here, we discuss key elements of such a framework, including cell type-based phenotyping, developmental trajectories, linking circuit properties at micro and macro scales and definition of neurobiological phenotypes that are directly translatable to humans.

  3. The plutonium extraction pilot plant at Chatillon; L'usine-pilote d'extraction du plutonium de Chatillon

    Energy Technology Data Exchange (ETDEWEB)

    Faugeras, P; Regnault, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    After a brief recapitulation of the problem and its difficulties, the chemical process and the apparatus used are described. The results obtained at the various stages of the separation are then given, as well as the performance by the apparatus. (author) [French] Apres un bref rappel du probleme et de ses difficultes, on decrit le procede chimique et l'appareillage utilises. On donne ensuite les resultats obtenus en ce qui concerne les divers stades de la separation ainsi que les performances fournies par les appareils. (auteur)

  4. Occupational Medicine Relevant to Aviation Medicine, Conference Proceedings of the Aerospace Medical Panel Symposium Held at London on 4 October 1983.

    Science.gov (United States)

    1984-05-01

    vivant . Sur comaande de la Direction des Recherches Etudes et Techniques (D.R.E.T.), le Centre d’Etudes et de Recherches de Mdecine Aerospatiale a...17000 51000 100 5.56 15 60 34.0 0.2 17000 78000 100 8.33 12.5 Tableau I - Bois de peuplier : recapitulation des rssultats. V (°C/mn) Pi (g) Pf (g) CO...60 30.0 (3.7) 10500 19500 35950 4400 15 100 5.56 1 Tableau II - PVC r6capitulation des rtsultats. (°C/mn) Pi (g) Pf (g) CO maxi CO2 maxi HCN maxi C3H8

  5. Permanent metabolic stimulation of leaves by low-dose irradiation

    International Nuclear Information System (INIS)

    Barabas, Z.

    1979-01-01

    By X-ray and colchicin treatment male-sterile mutants were produced from the Ra K9 Sorghum species. The characteristics of the mutants are compared with those of the original species. By this means the bisexual plant became unisexual, in later generations even asexual forms of reproduction were observed. This mutation chain is regarded as an artificially induced recapitulation of the natural evolution. Irradiation experiments were carried out in order to obtain wheat types resistant to brownrot, however, no success could be achieved with the present methods. (L.E.)

  6. Ways out of the environmental crisis

    International Nuclear Information System (INIS)

    Irrgang, B.; Klawitter, J.; Seif, K.P.

    1987-01-01

    The book documents the interdisciplinary papers held at a meeting on 'Ways out of the environmental crisis' in November 1985. Guided by the principle of concrete responsibilities emphasis was on the following subjects: Time presses - definition and consequences of the awareness of an imminent environmental catastrophe; air pollution and water pollution recapitulated; economic strategies for the benefit of pollution abatement; ethical and theological aspects; acceptable environmental policies - prospects and perspectives. The papers reflect the relation between the environment, the present generation, posterity, gross national producns and energy consumption, and present a number of scientifically founded alternative strategies. (HSCH) With 16 figs., 1 tab [de

  7. A designated centre for people with disabilities operated by Health Service Executive, Westmeath

    LENUS (Irish Health Repository)

    Mitchell, Kevin

    2011-11-11

    Abstract The number of individual cases of psychiatric disorders that can be ascribed to identified, rare, single mutations is increasing with great rapidity. Such mutations can be recapitulated in mice to generate animal models with direct etiological validity. Defining the underlying pathogenic mechanisms will require an experimental and theoretical framework to make the links from mutation to altered behavior in an animal or psychopathology in a human. Here, we discuss key elements of such a framework, including cell type-based phenotyping, developmental trajectories, linking circuit properties at micro and macro scales and definition of neurobiological phenotypes that are directly translatable to humans.

  8. G.A.M.I.N., the graphite neutron detector. Development and use in the dosimetry of radio-induced damages

    International Nuclear Information System (INIS)

    Cance, M.; Genthon, J.P.; Salon, L.; Micaud, G.

    1975-01-01

    The so-called G.A.M.I.N. graphite detector is well suited to determining fluences of radiation damage in reactor materials. It enables the measurement of the index (graphite damage flux)/(nickel flux). Measurements have been performing in Osiris and most of the testing reactors in Europe (H 2 O, D 2 O, G and fast). All measurements results are recapitulated here. It is shown how G.A.M.I.N. can determine note only graphite fluxes, but by a simple interpretation the damage fluxes typical of other materials [fr

  9. A program to develop advanced EBT [ELMO Bumpy Torus] concepts and international collaboration on the Bumpy Torus concept: Final report

    International Nuclear Information System (INIS)

    1987-01-01

    This project was undertaken to develop innovative concepts for improving the performance of ELMO Bumpy Torus devices in those aspects of plasma confinement that are particularly relevant to an eventual EBT reactor concept. These include effective magnetic utilization using Andreoletti coils, enhanced confinement using positive ambipolar potentials, and attractive divertor concepts that are compatible with formation and maintenance of ELMO rings. Each of the three major objectives was achieved and, except for the divertor studies, documented for publication and presentation at major scientific meetings. This report provides a brief recapitulation of the major results achieved in the form of a collection of those publications, together with this Introduction

  10. Loss of TET2 in hematopoietic cells leads to DNA hypermethylation of active enhancers and induction of leukemogenesis

    DEFF Research Database (Denmark)

    Rasmussen, Kasper D; Jia, Guangshuai; Johansen, Jens V

    2015-01-01

    DNA methylation is tightly regulated throughout mammalian development, and altered DNA methylation patterns are a general hallmark of cancer. The methylcytosine dioxygenase TET2 is frequently mutated in hematological disorders, including acute myeloid leukemia (AML), and has been suggested...... to protect CG dinucleotide (CpG) islands and promoters from aberrant DNA methylation. In this study, we present a novel Tet2-dependent leukemia mouse model that closely recapitulates gene expression profiles and hallmarks of human AML1-ETO-induced AML. Using this model, we show that the primary effect of Tet...

  11. Towards the future organization of the French gas industry

    International Nuclear Information System (INIS)

    Batail, J.

    1999-01-01

    This article recapitulates the content of the directive on the 'internal gas market', recalls the spirit of co-operation established with a view to developing the future gas system in France, and puts forward some to the questions raised within the framework of this co-operation. These include: public utilities, third party access to networks, the definition of future 'eligible consumers', the regulation necessary for the correct operation of the gas market on a competitive basis, and the development of French gas operators throughout the world. (author)

  12. Zebrafish: swimming towards a role for fanconi genes in DNA repair.

    Science.gov (United States)

    Scata, Kimberly A; El-Deiry, Wafik S

    2004-06-01

    The zebrafish, Danio rerio, has become a favorite model organism for geneticists and developmental biologists. Recently cancer biologists have turned to this tiny fish to help them unravel the mysteries of conserved pathways such as the Fanconi Anemia (FA) pathway. Although a relatively rare disease, the genes involved in FA are part of a large network of DNA damage response/repair genes. Liu and colleagues have recapitulated some of the clinical manifestations of human FA by knocking down the zebrafish FANC-D2 gene thereby providing a new model for probing the underlying causes of these phenotypes.

  13. W-Tagging/B-Veto in SUSY search for squarks and gluinos in final states with missing transverse energy, jets, and one isolated lepton at ATLAS

    CERN Document Server

    Reyer, Max

    2015-01-01

    This report recapitulates my stay at CERN as a Summer Student in a 13-week period from June 29 to September 25 in 2015. During that time, I was part of the CERN ATLAS Supersymmetry working group and working on a project exploiting W-tagging and B-veto techniques for the search for squarks and gluinos in final states with missing transverse energy, jets, and one isolated lepton. In this report, I will summarize my project and present results and conclusions. Apart from that, I will also write about my experience with the Summer Student lectures, the social aspects and the CERN Summer School in general.

  14. Deep learning in neural networks: an overview.

    Science.gov (United States)

    Schmidhuber, Jürgen

    2015-01-01

    In recent years, deep artificial neural networks (including recurrent ones) have won numerous contests in pattern recognition and machine learning. This historical survey compactly summarizes relevant work, much of it from the previous millennium. Shallow and Deep Learners are distinguished by the depth of their credit assignment paths, which are chains of possibly learnable, causal links between actions and effects. I review deep supervised learning (also recapitulating the history of backpropagation), unsupervised learning, reinforcement learning & evolutionary computation, and indirect search for short programs encoding deep and large networks.

  15. SORM applied to hierarchical parallel system

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager

    2006-01-01

    of a particular first order reliability method (FORM) was first described in a celebrated paper by Rackwitz and Fiessler more than a quarter of a century ago. The method has become known as the Rackwitz-Fiessler algorithm. The original RF-algorithm as applied to a hierarchical random variable model...... is recapitulated so that a simple but quite effective accuracy improving calculation can be explained. A limit state curvature correction factor on the probability approximation is obtained from the final stop results of the RF-algorithm. This correction factor is based on Breitung’s asymptotic formula for second...

  16. Kisspeptins: bridging energy homeostasis and reproduction

    DEFF Research Database (Denmark)

    Castellano, Juan M; Bentsen, Agnete H; Mikkelsen, Jens D

    2010-01-01

    and reproduction have been the subject of considerable attention; however, our understanding of the neurobiological basis for this phenomenon is still incomplete. In mid 1990s, the adipose-hormone, leptin, was proven as an essential signal for transmitting metabolic information onto the centers governing puberty......RH neurons. This review recapitulates the experimental evidence obtained to date, mostly in laboratory rodents, supporting the function of kisspeptins in bridging energy balance and reproduction, with special emphasis on recent developments in this field, such as the recognition of mTOR (mammalian target...

  17. A bio-inspired spatial patterning circuit.

    Science.gov (United States)

    Chen, Kai-Yuan; Joe, Danial J; Shealy, James B; Land, Bruce R; Shen, Xiling

    2014-01-01

    Lateral Inhibition (LI) is a widely conserved patterning mechanism in biological systems across species. Distinct from better-known Turing patterns, LI depend on cell-cell contact rather than diffusion. We built an in silico genetic circuit model to analyze the dynamic properties of LI. The model revealed that LI amplifies differences between neighboring cells to push them into opposite states, hence forming stable 2-D patterns. Inspired by this insight, we designed and implemented an electronic circuit that recapitulates LI patterning dynamics. This biomimetic system serve as a physical model to elucidate the design principle of generating robust patterning through spatial feedback, regardless of the underlying devices being biological or electrical.

  18. Spiral phases of doped antiferromagnets

    International Nuclear Information System (INIS)

    Shraiman, B.I.; Siggia, E.D.

    1990-01-01

    The dipole density field describing the holls in a doped antiferromagnet is considered for law hole density in the semiclassical limit. This yields a phase in which the order parameter is planar and spirals round a fixed direction. The single spiral state breaks the continuous spin rotational symmetry and exhibits long-range order at zero temperature. In it there is a global spin direction as rotation axis. The double spiral state, in which there are two perpendicular directions, is isotropic in both spin and real space. Several results of microscopic calculations, carried out to understand the electronic states, quantum fluctuations, lattice effects and normal mode dynamics, are recapitulated. 8 refs

  19. On the role of complexity in systems theory

    CSIR Research Space (South Africa)

    Greben, JM

    2009-01-01

    Full Text Available naturally leads to an explanation for the Big Bang and is not plagued by the horizon and cosmological constant problem. It naturally accommodates the notion of dark energy and proposes a possible explanation for dark matter. It leads to a dual description..., such as recapitulation, are also discussed. 25 March 2009 Keywords: Dark energy. Dark matter. Classical vacuum energy. Linear expansion of the universe. The role of energy conservation and vacuum energy in the evolution of the universe 2 1. Introduction In standard...

  20. PKD1 Mono-Allelic Knockout Is Sufficient to Trigger Renal Cystogenesis in a Mini-Pig Model

    OpenAIRE

    He, Jin; Li, Qiuyan; Fang, Suyun; Guo, Ying; Liu, Tongxin; Ye, Jianhua; Yu, Zhengquan; Zhang, Ran; Zhao, Yaofeng; Hu, Xiaoxiang; Bai, Xueyuan; Chen, Xiangmei; Li, Ning

    2015-01-01

    PKD1 and PKD2 mutations could lead to autosomal dominant polycystic kidney disease (ADPKD), which afflicts millions of people worldwide. Due to the marked differences in the lifespan, size, anatomy, and physiology from humans, rodent ADPKD models cannot fully mimic the disease. To obtain a large animal model that recapitulates the disease, we constructed a mini-pig model by mono-allelic knockout (KO) of PKD1 using zinc finger nuclease. The mono-allelic KO pigs had lower PKD1 expression than t...

  1. Risk Acceptance Criteria and/or Decision optimization

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager

    1996-01-01

    Acceptance criteria applied in practical risk analysis are recapitulated including the concept of rist profile. Modelling of risk profiles is illustrated on the basis of compound Poisson process models. The current practice of authoritative acceptance criteria formulation is discussed from...... a decision theoretical point of view. It is argued that the phenomenon of risk aversion rather than being of concern to the authority should be of concern to the owner. Finally it is discussed whether there is an ethical problem when formally capitalising human lives with a positive interest rate. Keywords......: Risk acceptance, Risk profile, Compound Poisson model for risk profile, Capitalization of human life, Risk aversion....

  2. Purification and final concentration of the plutonium obtained by treatment of irradiated uranium at the Fontenay-aux-Roses pilot plant; Purification et concentration finales du plutonium en fin de traitement de l'uranium irradie a l'usine-pilote de Fontenay-aux-Roses

    Energy Technology Data Exchange (ETDEWEB)

    Prevot, I; Corpel, J; Regnaut, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    This paper consists of: 1- a recapitulation of the laboratory tests which led to the choice of the method; 2- a description of the latter, with the results obtained at the Fontenay-aux-Roses pilot plant; 3- the analytical methods used for checking and verifying the purity of the plutonium. (author)Fren. [French] Cet expose comprend: 1- le rappel des essais de laboratoire qui ont conduit au choix du procede; 2- la description de ce dernier, avec les resultats obtenus a l'Usine-Pilote de Fontenay-aux-Roses; 3- les methodes analytiques utilisees pour le controle et pour la verification de la purete du plutonium. (auteur)

  3. Ground rules of the pluripotency gene regulatory network.

    KAUST Repository

    Li, Mo; Belmonte, Juan Carlos Izpisua

    2017-01-01

    Pluripotency is a state that exists transiently in the early embryo and, remarkably, can be recapitulated in vitro by deriving embryonic stem cells or by reprogramming somatic cells to become induced pluripotent stem cells. The state of pluripotency, which is stabilized by an interconnected network of pluripotency-associated genes, integrates external signals and exerts control over the decision between self-renewal and differentiation at the transcriptional, post-transcriptional and epigenetic levels. Recent evidence of alternative pluripotency states indicates the regulatory flexibility of this network. Insights into the underlying principles of the pluripotency network may provide unprecedented opportunities for studying development and for regenerative medicine.

  4. Covariance dynamics and symmetries, and hadron form factors

    International Nuclear Information System (INIS)

    Bhagwat, M.S.; Cloet, I.C.; Roberts, C.D.

    2007-01-01

    We summarize applications of Dyson-Schwinger equations to the theory and phenomenology of hadrons. Some exact results for pseudoscalar mesons are highlighted with details relating to the U A (1) problem. We describe inferences from the gap equation relating to the radius of convergence for expansions of observables in the current-quark mass. We recapitulate upon studies of nucleon electromagnetic form factors, providing a comparison of the ln-weighted ratios of Pauli and Dirac form factors for the neutron and proton.

  5. Energy policy of the International Energy Agency (IEA) countries. General review of the year 1990

    International Nuclear Information System (INIS)

    1992-01-01

    This book is a general review on energy policy leaded by Members countries of International Energy Agency (IEA) during the year 1990. This book describes also the trends and the recent events which have affected energy demand, energy conservation, energy efficiency, energy supply and energy source development. This annual review gives the IEA energy forecasting for the next years, till year 2001. A detailed study of energy policy in Federal Republic of Germany, Austria, Denmark, Greece, Ireland and Japan is given. The policy of fifteen another Members countries, which have been analyzed the previous years, is recapitulated and briefly brought up to date

  6. A neurite quality index and machine vision software for improved quantification of neurodegeneration.

    Science.gov (United States)

    Romero, Peggy; Miller, Ted; Garakani, Arman

    2009-12-01

    Current methods to assess neurodegradation in dorsal root ganglion cultures as a model for neurodegenerative diseases are imprecise and time-consuming. Here we describe two new methods to quantify neuroprotection in these cultures. The neurite quality index (NQI) builds upon earlier manual methods, incorporating additional morphological events to increase detection sensitivity for the detection of early degeneration events. Neurosight is a machine vision-based method that recapitulates many of the strengths of NQI while enabling high-throughput screening applications with decreased costs.

  7. Proceedings of CAS - CERN Accelerator School: Course on Superconductivity for Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, R [European Organization for Nuclear Research, Geneva (Switzerland)

    2014-07-01

    These proceedings collate lectures given at the twenty-seventh specialized course organised by the CERN Accelerator School (CAS). The course was held at the Ettore Majorana Foundation and Centre for Scientific Culture (EMFCSC) in Erice, Italy, from 24 April to 4 May 2013. Following recapitulation lectures on basic accelerator physics and superconductivity, the course covered topics related to the design, production and operation of superconducting RF systems and superconducting magnets for accelerators. The participants pursued one of six case studies in order to get ’hands-on’ experience of the issues connected with the design of superconducting systems. A series of topical seminars completed the programme.

  8. Experimental cancer cachexia: Evolving strategies for getting closer to the human scenario.

    Science.gov (United States)

    Penna, Fabio; Busquets, Sílvia; Argilés, Josep M

    2016-06-01

    Cancer cachexia is a frequent syndrome that dramatically affects patient quality of life, anti-cancer treatment effectiveness, and overall survival. To date, no effective treatment is available and most of the studies are performed in experimental models in order to uncover the underlying mechanisms and to design prospective therapeutic strategies. This review summarizes the most relevant information regarding the use of animal models for studying cancer cachexia. Technical limitations and degree of recapitulation of the features of human cachexia are highlighted, in order to help investigators choose the most suitable model according to study-specific endpoints. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Adenovirus Protein E4-ORF1 activation of PI3 kinase reveals differential regulation of downstream effector pathways in adipocytes

    OpenAIRE

    Chaudhary, Natasha; Gonzalez, Eva; Chang, Sung-Hee; Geng, Fuqiang; Rafii, Shahin; Altorki, Nasser K.; McGraw, Timothy E.

    2016-01-01

    Insulin activation of phosphatidylinositol 3-kinase (PI3K) regulates metabolism, including the translocation of the Glut4 glucose transporter to the plasma membrane and inactivation of the FoxO1 transcription factor. Adenoviral protein E4-ORF1 stimulates cellular glucose metabolism by mimicking growth-factor activation of PI3K. We have used E4-ORF1 as a tool to dissect PI3K-mediated signaling in adipocytes. E4-ORF1 activation of PI3K in adipocytes recapitulates insulin regulation of FoxO1 but...

  10. Notas sobre las transformaciones psíquicas de la adolescencia en la historia del psicoanálisis

    Directory of Open Access Journals (Sweden)

    Mauricio Fernández Arcila

    2014-07-01

    Full Text Available The determinism of childhood captured the attention of psychoanalytic thought and overshadowed the crucial role of adolescence, which Freud himself recognized. New approaches to the specificity and importance of adolescence begin to crop up in the mid-twentieth century, supported in clinical practice with adolescents developed after WWII. Finally the integration of the concept of "afterwards" {Nachträglichkeit} in these theories best validates the thesis that adolescent psychic transformations are not confined to the recapitulation of previous problems.

  11. Clock force. Universe, time, and future

    International Nuclear Information System (INIS)

    Karb, W.

    2005-01-01

    In a dialog full of esprite two protagonists of the sides of physics and philosophy struggle about answers on great questions. As witnesses occur the great phsicists and philosophers, the theories and discoveries of them Karb recapitulates in easily understandable form and puts together into relation. Karb advertizes for pragmatic and responsible ethics in the sciences. Always within the great theories themselves Karb argumentates that theoretical physics is indeed not at the end, but it should have an end with always new billions expensive collider facilities, which serve lonely for the hybris of scientists

  12. Trends in domestic violence service and leadership: implications for an integrated shelter model.

    Science.gov (United States)

    Panzer, P G; Philip, M B; Hayward, R A

    2000-05-01

    Domestic violence is a dangerous and prevalent social problem affecting up to 4 million women and countless children annually. Shelters offer safety and an opportunity for change during the crisis of family violence. These individuals also have the potential for retraumatization if leadership within the program recapitulates the abuse and coercion felt at home. This article reviews three related trends through the lens of power and control--domestic violence policy and service, models of leadership, and the study of traumatic stress disorders and recovery--and describes their implications for modern shelter service delivery.

  13. On endogenous order of moves in a trade embargo game

    International Nuclear Information System (INIS)

    Ngueyen Manh Hung

    1991-01-01

    Hung and Quyen's model (analysis of strategic interactions between players in the game theoretic framework) is first recapitulated. Solutions to the embargo game with the seller acting as the Stackelberg leader in both periods. Then the timing coordination issue is discussed and perfect equilibrium outcomes under different structures of leader-follower in the game are compared. Numerical simulations show that the structure corresponding to alternated leadership from one period to the other yields the perfect equilibrium outcome that is Pareto improving with respect to the structure where the buyer is first mover in both periods and Pareto dominant for some specific values of the parameters embedded in the game

  14. From Immunodeficiency to Humanization: The Contribution of Mouse Models to Explore HTLV-1 Leukemogenesis

    Directory of Open Access Journals (Sweden)

    Eléonore Pérès

    2015-12-01

    Full Text Available The first discovered human retrovirus, Human T-Lymphotropic Virus type 1 (HTLV-1, is responsible for an aggressive form of T cell leukemia/lymphoma. Mouse models recapitulating the leukemogenesis process have been helpful for understanding the mechanisms underlying the pathogenesis of this retroviral-induced disease. This review will focus on the recent advances in the generation of immunodeficient and human hemato-lymphoid system mice with a particular emphasis on the development of mouse models for HTLV-1-mediated pathogenesis, their present limitations and the challenges yet to be addressed.

  15. Cerebellar Ataxia and Coenzyme Q Deficiency Through Loss of Unorthodox Kinase Activity

    OpenAIRE

    Stefely, Jonathan A.; Licitra, Floriana; Laredj, Leila; Reidenbach, Andrew G.; Kemmerer, Zachary A.; Grangeray, Anais; Jaeg-Ehret, Tiphaine; Minogue, Catherine E.; Ulbrich, Arne; Hutchins, Paul D.; Wilkerson, Emily M.; Ruan, Zheng; Aydin, Deniz; Hebert, Alexander S.; Guo, Xiao

    2016-01-01

    The UbiB protein kinase-like (PKL) family is widespread—comprising one-quarter of microbial PKLs and five human homologs—yet its biochemical activities remain obscure. COQ8A (ADCK3) is a mammalian UbiB protein associated with ubiquinone (CoQ) biosynthesis and an ataxia (ARCA2) through unclear means. We show that mice lacking COQ8A develop a slowly progressive cerebellar ataxia linked to Purkinje cell dysfunction and mild exercise intolerance, recapitulating ARCA2. Interspecies biochemical ana...

  16. A designated centre for people with disabilities operated by Camphill Communities of Ireland, Kilkenny

    LENUS (Irish Health Repository)

    Mitchell, Kevin

    2011-11-11

    Abstract The number of individual cases of psychiatric disorders that can be ascribed to identified, rare, single mutations is increasing with great rapidity. Such mutations can be recapitulated in mice to generate animal models with direct etiological validity. Defining the underlying pathogenic mechanisms will require an experimental and theoretical framework to make the links from mutation to altered behavior in an animal or psychopathology in a human. Here, we discuss key elements of such a framework, including cell type-based phenotyping, developmental trajectories, linking circuit properties at micro and macro scales and definition of neurobiological phenotypes that are directly translatable to humans.

  17. Tissue-Mimicking Geometrical Constraints Stimulate Tissue-Like Constitution and Activity of Mouse Neonatal and Human-Induced Pluripotent Stem Cell-Derived Cardiac Myocytes

    Directory of Open Access Journals (Sweden)

    Götz Pilarczyk

    2016-01-01

    Full Text Available The present work addresses the question of to what extent a geometrical support acts as a physiological determining template in the setup of artificial cardiac tissue. Surface patterns with alternating concave to convex transitions of cell size dimensions were used to organize and orientate human-induced pluripotent stem cell (hIPSC-derived cardiac myocytes and mouse neonatal cardiac myocytes. The shape of the cells, as well as the organization of the contractile apparatus recapitulates the anisotropic line pattern geometry being derived from tissue geometry motives. The intracellular organization of the contractile apparatus and the cell coupling via gap junctions of cell assemblies growing in a random or organized pattern were examined. Cell spatial and temporal coordinated excitation and contraction has been compared on plain and patterned substrates. While the α-actinin cytoskeletal organization is comparable to terminally-developed native ventricular tissue, connexin-43 expression does not recapitulate gap junction distribution of heart muscle tissue. However, coordinated contractions could be observed. The results of tissue-like cell ensemble organization open new insights into geometry-dependent cell organization, the cultivation of artificial heart tissue from stem cells and the anisotropy-dependent activity of therapeutic compounds.

  18. EFFORTS TO INCREASE THE ABILITY TO CHOOSE A SCHOOL GROUP COUNSELING SERVICES THROUGH ADVANCED CLASS IX SMP NEGERI 2 METRO STATE IN 2013

    Directory of Open Access Journals (Sweden)

    Rohima Rohima

    2016-06-01

    Full Text Available SMP Negeri 2 Metro In reality, there are many confused students choose a major program of advanced studies, especially for junior high school students. It is necessary to learn / coaching to the students to be able to choose the school accordingly. Researchers conduct action research through the Guidance Counseling Group in Class IX student of SMP Negeri 2 Metro. The experiment was conducted using two cycles. Recapitulation of data Selecting a program majoring in the process of learning / coaching from the first cycle to the second cycle, there is an increase of 57.06% to 86.35%. The results of the data summary portfolio also increased from 33.32% to 83.33%, and the recapitulation of learning outcomes of students who otherwise Completed Pass also risen from 54.54% increase to 96.96%. Thus concluded indicator of success is to reach the target / as are 95% or more. Keywords: guidance group, select schools, smp negeri 2 metro

  19. In Vitro Modeling of Human Germ Cell Development Using Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Yuncheng Zhao

    2018-02-01

    Full Text Available Summary: Due to differences across species, the mechanisms of cell fate decisions determined in mice cannot be readily extrapolated to humans. In this study, we developed a feeder- and xeno-free culture protocol that efficiently induced human pluripotent stem cells (iPSCs into PLZF+/GPR125+/CD90+ spermatogonium-like cells (SLCs. These SLCs were enriched with key genes in germ cell development such as MVH, DAZL, GFRα1, NANOS3, and DMRT1. In addition, a small fraction of SLCs went through meiosis in vitro to develop into haploid cells. We further demonstrated that this chemically defined induction protocol faithfully recapitulated the features of compromised germ cell development of PSCs with NANOS3 deficiency or iPSC lines established from patients with non-obstructive azoospermia. Taken together, we established a powerful experimental platform to investigate human germ cell development and pathology related to male infertility. : In this article, Wang and colleagues established a feeder- and xeno-free system to robustly induce human pluripotent stem cells (PSCs into spermatogonia-like cells. This chemically defined induction protocol faithfully recapitulated the features of compromised germ cell development of PSCs with NANOS3 deficiency or iPSC lines established from patients with non-obstructive azoospermia. Keywords: pluripotent stem cells, spermatogonia, infertility, non-obstructive azoospermia

  20. Roles of PAD4 and NETosis in Experimental Atherosclerosis and Arterial Injury: Implications for Superficial Erosion.

    Science.gov (United States)

    Franck, Grégory; Mawson, Thomas L; Folco, Eduardo J; Molinaro, Roberto; Ruvkun, Victoria; Engelbertsen, Daniel; Liu, Xin; Tesmenitsky, Yevgenia; Shvartz, Eugenia; Sukhova, Galina K; Michel, Jean-Baptiste; Nicoletti, Antonino; Lichtman, Andrew; Wagner, Denisa; Croce, Kevin J; Libby, Peter

    2018-06-22

    Neutrophils likely contribute to the thrombotic complications of human atheromata. In particular, neutrophil extracellular traps (NETs) could exacerbate local inflammation and amplify and propagate arterial intimal injury and thrombosis. PAD4 (peptidyl arginine deiminase 4) participates in NET formation, but an understanding of this enzyme's role in atherothrombosis remains scant. This study tested the hypothesis that PAD4 and NETs influence experimental atherogenesis and in processes implicated in superficial erosion, a form of plaque complication we previously associated with NETs. Bone marrow chimeric Ldlr deficient mice reconstituted with either wild-type or PAD4-deficient cells underwent studies that assessed atheroma formation or procedures designed to probe mechanisms related to superficial erosion. PAD4 deficiency neither retarded fatty streak formation nor reduced plaque size or inflammation in bone marrow chimeric mice that consumed an atherogenic diet. In contrast, either a PAD4 deficiency in bone marrow-derived cells or administration of DNaseI to disrupt NETs decreased the extent of arterial intimal injury in mice with arterial lesions tailored to recapitulate characteristics of human atheroma complicated by erosion. These results indicate that PAD4 from bone marrow-derived cells and NETs do not influence chronic experimental atherogenesis, but participate causally in acute thrombotic complications of intimal lesions that recapitulate features of superficial erosion. © 2018 American Heart Association, Inc.

  1. Stereotactic intracranial implantation and in vivo bioluminescent imaging of tumor xenografts in a mouse model system of glioblastoma multiforme.

    Science.gov (United States)

    Baumann, Brian C; Dorsey, Jay F; Benci, Joseph L; Joh, Daniel Y; Kao, Gary D

    2012-09-25

    Glioblastoma multiforme (GBM) is a high-grade primary brain cancer with a median survival of only 14.6 months in humans despite standard tri-modality treatment consisting of surgical resection, post-operative radiation therapy and temozolomide chemotherapy. New therapeutic approaches are clearly needed to improve patient survival and quality of life. The development of more effective treatment strategies would be aided by animal models of GBM that recapitulate human disease yet allow serial imaging to monitor tumor growth and treatment response. In this paper, we describe our technique for the precise stereotactic implantation of bio-imageable GBM cancer cells into the brains of nude mice resulting in tumor xenografts that recapitulate key clinical features of GBM. This method yields tumors that are reproducible and are located in precise anatomic locations while allowing in vivo bioluminescent imaging to serially monitor intracranial xenograft growth and response to treatments. This method is also well-tolerated by the animals with low perioperative morbidity and mortality.

  2. Epstein–Barr virus glycoprotein gM can interact with the cellular protein p32 and knockdown of p32 impairs virus

    International Nuclear Information System (INIS)

    Changotra, Harish; Turk, Susan M.; Artigues, Antonio; Thakur, Nagendra; Gore, Mindy; Muggeridge, Martin I.; Hutt-Fletcher, Lindsey M.

    2016-01-01

    The Epstein–Barr virus glycoprotein complex gMgN has been implicated in assembly and release of fully enveloped virus, although the precise role that it plays has not been elucidated. We report here that the long predicted cytoplasmic tail of gM is not required for complex formation and that it interacts with the cellular protein p32, which has been reported to be involved in nuclear egress of human cytomegalovirus and herpes simplex virus. Although redistribution of p32 and colocalization with gM was not observed in virus infected cells, knockdown of p32 expression by siRNA or lentivirus-delivered shRNA recapitulated the phenotype of a virus lacking expression of gNgM. A proportion of virus released from cells sedimented with characteristics of virus lacking an intact envelope and there was an increase in virus trapped in nuclear condensed chromatin. The observations suggest the possibility that p32 may also be involved in nuclear egress of Epstein–Barr virus. - Highlights: • The predicted cytoplasmic tail of gM is not required to complex with gN. • Cellular p32 can interact with the predicted cytoplasmic tail of EBV gM. • Knockdown of p32 recapitulates the phenotype of virus lacking the gNgM complex.

  3. Disease Modeling Using 3D Organoids Derived from Human Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Ho, Beatrice Xuan; Pek, Nicole Min Qian; Soh, Boon-Seng

    2018-03-21

    The rising interest in human induced pluripotent stem cell (hiPSC)-derived organoid culture has stemmed from the manipulation of various combinations of directed multi-lineage differentiation and morphogenetic processes that mimic organogenesis. Organoids are three-dimensional (3D) structures that are comprised of multiple cell types, self-organized to recapitulate embryonic and tissue development in vitro. This model has been shown to be superior to conventional two-dimensional (2D) cell culture methods in mirroring functionality, architecture, and geometric features of tissues seen in vivo. This review serves to highlight recent advances in the 3D organoid technology for use in modeling complex hereditary diseases, cancer, host-microbe interactions, and possible use in translational and personalized medicine where organoid cultures were used to uncover diagnostic biomarkers for early disease detection via high throughput pharmaceutical screening. In addition, this review also aims to discuss the advantages and shortcomings of utilizing organoids in disease modeling. In summary, studying human diseases using hiPSC-derived organoids may better illustrate the processes involved due to similarities in the architecture and microenvironment present in an organoid, which also allows drug responses to be properly recapitulated in vitro.

  4. Sex-Specific Skeletal Muscle Fatigability and Decreased Mitochondrial Oxidative Capacity in Adult Rats Exposed to Postnatal Hyperoxia

    Directory of Open Access Journals (Sweden)

    Laura H. Tetri

    2018-03-01

    Full Text Available Premature birth affects more than 10% of live births, and is characterized by relative hyperoxia exposure in an immature host. Long-term consequences of preterm birth include decreased aerobic capacity, decreased muscular strength and endurance, and increased prevalence of metabolic diseases such as type 2 diabetes mellitus. Postnatal hyperoxia exposure in rodents is a well-established model of chronic lung disease of prematurity, and also recapitulates the pulmonary vascular, cardiovascular, and renal phenotype of premature birth. The objective of this study was to evaluate whether postnatal hyperoxia exposure in rats could recapitulate the skeletal and metabolic phenotype of premature birth, and to characterize the subcellular metabolic changes associated with postnatal hyperoxia exposure, with a secondary aim to evaluate sex differences in this model. Compared to control rats, male rats exposed to 14 days of postnatal hyperoxia then aged to 1 year demonstrated higher skeletal muscle fatigability, lower muscle mitochondrial oxidative capacity, more mitochondrial damage, and higher glycolytic enzyme expression. These differences were not present in female rats with the same postnatal hyperoxia exposure. This study demonstrates detrimental mitochondrial and muscular outcomes in the adult male rat exposed to postnatal hyperoxia. Given that young adults born premature also demonstrate skeletal muscle dysfunction, future studies are merited to determine whether this dysfunction as well as reduced aerobic capacity is due to reduced mitochondrial oxidative capacity and metabolic dysfunction.

  5. Manipulation of host factors optimizes the pathogenesis of western equine encephalitis virus infections in mice for antiviral drug development

    Science.gov (United States)

    Blakely, Pennelope K.; Delekta, Phillip C.; Miller, David J.; Irani, David N.

    2014-01-01

    While alphaviruses spread naturally via mosquito vectors, some can also be transmitted as aerosols making them potential bioterrorism agents. One such pathogen, western equine encephalitis virus (WEEV), causes fatal human encephalitis via multiple routes of infection and thus presumably via multiple mechanisms. Although WEEV also produces acute encephalitis in non-human primates, a small animal model that recapitulates features of human disease would be useful for both pathogenesis studies and to evaluate candidate antiviral therapies. We have optimized conditions to infect mice with a low passage isolate of WEEV, thereby allowing detailed investigation of virus tropism, replication, neuroinvasion, and neurovirulence. We find that host factors strongly influence disease outcome, and in particular that age, gender and genetic background all have significant effects on disease susceptibility independent of virus tropism or replication within the central nervous system. Our data show that experimental variables can be adjusted in mice to recapitulate disease features known to occur in both non-human primates and humans, thus aiding further study of WEEV pathogenesis and providing a realistic therapeutic window for antiviral drug delivery. PMID:25361697

  6. A hierarchy of time-scales and the brain.

    Science.gov (United States)

    Kiebel, Stefan J; Daunizeau, Jean; Friston, Karl J

    2008-11-01

    In this paper, we suggest that cortical anatomy recapitulates the temporal hierarchy that is inherent in the dynamics of environmental states. Many aspects of brain function can be understood in terms of a hierarchy of temporal scales at which representations of the environment evolve. The lowest level of this hierarchy corresponds to fast fluctuations associated with sensory processing, whereas the highest levels encode slow contextual changes in the environment, under which faster representations unfold. First, we describe a mathematical model that exploits the temporal structure of fast sensory input to track the slower trajectories of their underlying causes. This model of sensory encoding or perceptual inference establishes a proof of concept that slowly changing neuronal states can encode the paths or trajectories of faster sensory states. We then review empirical evidence that suggests that a temporal hierarchy is recapitulated in the macroscopic organization of the cortex. This anatomic-temporal hierarchy provides a comprehensive framework for understanding cortical function: the specific time-scale that engages a cortical area can be inferred by its location along a rostro-caudal gradient, which reflects the anatomical distance from primary sensory areas. This is most evident in the prefrontal cortex, where complex functions can be explained as operations on representations of the environment that change slowly. The framework provides predictions about, and principled constraints on, cortical structure-function relationships, which can be tested by manipulating the time-scales of sensory input.

  7. A hierarchy of time-scales and the brain.

    Directory of Open Access Journals (Sweden)

    Stefan J Kiebel

    2008-11-01

    Full Text Available In this paper, we suggest that cortical anatomy recapitulates the temporal hierarchy that is inherent in the dynamics of environmental states. Many aspects of brain function can be understood in terms of a hierarchy of temporal scales at which representations of the environment evolve. The lowest level of this hierarchy corresponds to fast fluctuations associated with sensory processing, whereas the highest levels encode slow contextual changes in the environment, under which faster representations unfold. First, we describe a mathematical model that exploits the temporal structure of fast sensory input to track the slower trajectories of their underlying causes. This model of sensory encoding or perceptual inference establishes a proof of concept that slowly changing neuronal states can encode the paths or trajectories of faster sensory states. We then review empirical evidence that suggests that a temporal hierarchy is recapitulated in the macroscopic organization of the cortex. This anatomic-temporal hierarchy provides a comprehensive framework for understanding cortical function: the specific time-scale that engages a cortical area can be inferred by its location along a rostro-caudal gradient, which reflects the anatomical distance from primary sensory areas. This is most evident in the prefrontal cortex, where complex functions can be explained as operations on representations of the environment that change slowly. The framework provides predictions about, and principled constraints on, cortical structure-function relationships, which can be tested by manipulating the time-scales of sensory input.

  8. Kidney branching morphogenesis under the control of a ligand–receptor-based Turing mechanism

    International Nuclear Information System (INIS)

    Menshykau, Denis; Iber, Dagmar

    2013-01-01

    The main signalling proteins that control early kidney branching have been defined. Yet the underlying mechanism is still elusive. We have previously shown that a Schnakenberg-type Turing mechanism can recapitulate the branching and protein expression patterns in wild-type and mutant lungs, but it is unclear whether this mechanism would extend to other branched organs that are regulated by other proteins. Here, we show that the glial cell line-derived neurotrophic factor–RET regulatory interaction gives rise to a Schnakenberg-type Turing model that reproduces the observed budding of the ureteric bud from the Wolffian duct, its invasion into the mesenchyme and the observed branching pattern. The model also recapitulates all relevant protein expression patterns in wild-type and mutant mice. The lung and kidney models are both based on a particular receptor–ligand interaction and require (1) cooperative binding of ligand and receptor, (2) a lower diffusion coefficient for the receptor than for the ligand and (3) an increase in the receptor concentration in response to receptor–ligand binding (by enhanced transcription, more recycling or similar). These conditions are met also by other receptor–ligand systems. We propose that ligand–receptor-based Turing patterns represent a general mechanism to control branching morphogenesis and other developmental processes. (paper)

  9. Glutamate and GABA in autism spectrum disorder-a translational magnetic resonance spectroscopy study in man and rodent models.

    Science.gov (United States)

    Horder, Jamie; Petrinovic, Marija M; Mendez, Maria A; Bruns, Andreas; Takumi, Toru; Spooren, Will; Barker, Gareth J; Künnecke, Basil; Murphy, Declan G

    2018-05-25

    Autism spectrum disorder (ASD) is a pervasive neurodevelopmental syndrome with a high human and economic burden. The pathophysiology of ASD is largely unclear, thus hampering development of pharmacological treatments for the core symptoms of the disorder. Abnormalities in glutamate and GABA signaling have been hypothesized to underlie ASD symptoms, and may form a therapeutic target, but it is not known whether these abnormalities are recapitulated in humans with ASD, as well as in rodent models of the disorder. We used translational proton magnetic resonance spectroscopy ([1H]MRS) to compare glutamate and GABA levels in adult humans with ASD and in a panel of six diverse rodent ASD models, encompassing genetic and environmental etiologies. [1H]MRS was performed in the striatum and the medial prefrontal cortex, of the humans, mice, and rats in order to allow for direct cross-species comparisons in specific cortical and subcortical brain regions implicated in ASD. In humans with ASD, glutamate concentration was reduced in the striatum and this was correlated with the severity of social symptoms. GABA levels were not altered in either brain region. The reduction in striatal glutamate was recapitulated in mice prenatally exposed to valproate, and in mice and rats carrying Nlgn3 mutations, but not in rodent ASD models with other etiologies. Our findings suggest that glutamate/GABA abnormalities in the corticostriatal circuitry may be a key pathological mechanism in ASD; and may be linked to alterations in the neuroligin-neurexin signaling complex.

  10. Three-dimensional bioprinting using self-assembling scalable scaffold-free “tissue strands” as a new bioink

    Science.gov (United States)

    Yu, Yin; Moncal, Kazim K.; Li, Jianqiang; Peng, Weijie; Rivero, Iris; Martin, James A.; Ozbolat, Ibrahim T.

    2016-01-01

    Recent advances in bioprinting have granted tissue engineers the ability to assemble biomaterials, cells, and signaling molecules into anatomically relevant functional tissues or organ parts. Scaffold-free fabrication has recently attracted a great deal of interest due to the ability to recapitulate tissue biology by using self-assembly, which mimics the embryonic development process. Despite several attempts, bioprinting of scale-up tissues at clinically-relevant dimensions with closely recapitulated tissue biology and functionality is still a major roadblock. Here, we fabricate and engineer scaffold-free scalable tissue strands as a novel bioink material for robotic-assisted bioprinting technologies. Compare to 400 μm-thick tissue spheroids bioprinted in a liquid delivery medium into confining molds, near 8 cm-long tissue strands with rapid fusion and self-assemble capabilities are bioprinted in solid form for the first time without any need for a scaffold or a mold support or a liquid delivery medium, and facilitated native-like scale-up tissues. The prominent approach has been verified using cartilage strands as building units to bioprint articular cartilage tissue. PMID:27346373

  11. Chemotaxis in densely populated tissue determines germinal center anatomy and cell motility: a new paradigm for the development of complex tissues.

    Directory of Open Access Journals (Sweden)

    Jared B Hawkins

    Full Text Available Germinal centers (GCs are complex dynamic structures that form within lymph nodes as an essential process in the humoral immune response. They represent a paradigm for studying the regulation of cell movement in the development of complex anatomical structures. We have developed a simulation of a modified cyclic re-entry model of GC dynamics which successfully employs chemotaxis to recapitulate the anatomy of the primary follicle and the development of a mature GC, including correctly structured mantle, dark and light zones. We then show that correct single cell movement dynamics (including persistent random walk and inter-zonal crossing arise from this simulation as purely emergent properties. The major insight of our study is that chemotaxis can only achieve this when constrained by the known biological properties that cells are incompressible, exist in a densely packed environment, and must therefore compete for space. It is this interplay of chemotaxis and competition for limited space that generates all the complex and biologically accurate behaviors described here. Thus, from a single simple mechanism that is well documented in the biological literature, we can explain both higher level structure and single cell movement behaviors. To our knowledge this is the first GC model that is able to recapitulate both correctly detailed anatomy and single cell movement. This mechanism may have wide application for modeling other biological systems where cells undergo complex patterns of movement to produce defined anatomical structures with sharp tissue boundaries.

  12. Chemotaxis in densely populated tissue determines germinal center anatomy and cell motility: a new paradigm for the development of complex tissues.

    Science.gov (United States)

    Hawkins, Jared B; Jones, Mark T; Plassmann, Paul E; Thorley-Lawson, David A

    2011-01-01

    Germinal centers (GCs) are complex dynamic structures that form within lymph nodes as an essential process in the humoral immune response. They represent a paradigm for studying the regulation of cell movement in the development of complex anatomical structures. We have developed a simulation of a modified cyclic re-entry model of GC dynamics which successfully employs chemotaxis to recapitulate the anatomy of the primary follicle and the development of a mature GC, including correctly structured mantle, dark and light zones. We then show that correct single cell movement dynamics (including persistent random walk and inter-zonal crossing) arise from this simulation as purely emergent properties. The major insight of our study is that chemotaxis can only achieve this when constrained by the known biological properties that cells are incompressible, exist in a densely packed environment, and must therefore compete for space. It is this interplay of chemotaxis and competition for limited space that generates all the complex and biologically accurate behaviors described here. Thus, from a single simple mechanism that is well documented in the biological literature, we can explain both higher level structure and single cell movement behaviors. To our knowledge this is the first GC model that is able to recapitulate both correctly detailed anatomy and single cell movement. This mechanism may have wide application for modeling other biological systems where cells undergo complex patterns of movement to produce defined anatomical structures with sharp tissue boundaries.

  13. Fabrication of Trabecular Bone-Templated Tissue-Engineered Constructs by 3D Inkjet Printing.

    Science.gov (United States)

    Vanderburgh, Joseph P; Fernando, Shanik J; Merkel, Alyssa R; Sterling, Julie A; Guelcher, Scott A

    2017-11-01

    3D printing enables the creation of scaffolds with precisely controlled morphometric properties for multiple tissue types, including musculoskeletal tissues such as cartilage and bone. Computed tomography (CT) imaging has been combined with 3D printing to fabricate anatomically scaled patient-specific scaffolds for bone regeneration. However, anatomically scaled scaffolds typically lack sufficient resolution to recapitulate the 3D constructs are fabricated via a new micro-CT/3D inkjet printing process. It is shown that this process reproducibly fabricates bone-templated constructs that recapitulate the anatomic site-specific morphometric properties of trabecular bone. A significant correlation is observed between the structure model index (a morphometric parameter related to surface curvature) and the degree of mineralization of human mesenchymal stem cells, with more concave surfaces promoting more extensive osteoblast differentiation and mineralization compared to predominately convex surfaces. These findings highlight the significant effects of trabecular architecture on osteoblast function. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Truncated C-terminus of fibrillin-1 induces Marfanoid-progeroid-lipodystrophy (MPL) syndrome in rabbit.

    Science.gov (United States)

    Chen, Mao; Yao, Bing; Yang, Qiangbing; Deng, Jichao; Song, Yuning; Sui, Tingting; Zhou, Lina; Yao, HaoBing; Xu, Yuanyuan; Ouyang, Hongsheng; Pang, Daxin; Li, Zhanjun; Lai, Liangxue

    2018-04-09

    Various clinical differences have been observed between patients with the FBN1 gene mutation and those with the classical Marfan phenotype. Although FBN1 knockout (KO) or dominant-negative mutant mice are widely used as an animal model for Marfan syndrome (MFS), these mice cannot recapitulate the genotype/phenotype relationship of Marfanoid-progeroid-lipodystrophy (MPL) syndrome, which is caused by a mutation in the C-terminus of fibrillin-1, the penultimate exon of the FBN1 gene. Here, we describe the generation of a rabbit MPL model with C-terminal truncation of fibrillin-1 using a CRISPR/Cas9 system. FBN1 heterozygous ( FBN1 Het) rabbits faithfully recapitulated the phenotypes of MFS, including muscle wasting and impaired connective tissue, ocular syndrome and aortic dilation. Moreover, skin symptoms, lipodystrophy, growth retardation and dysglycemia were also seen in these FBN1 Het rabbits, and have not been reported in other animal models. In conclusion, this novel rabbit model mimics the histopathological changes and functional defects of MPL syndrome, and could become a valuable model for studies of pathogenesis and drug screening for MPL syndrome. © 2018. Published by The Company of Biologists Ltd.

  15. Whole-Body Vibration Mimics the Metabolic Effects of Exercise in Male Leptin Receptor-Deficient Mice.

    Science.gov (United States)

    McGee-Lawrence, Meghan E; Wenger, Karl H; Misra, Sudipta; Davis, Catherine L; Pollock, Norman K; Elsalanty, Mohammed; Ding, Kehong; Isales, Carlos M; Hamrick, Mark W; Wosiski-Kuhn, Marlena; Arounleut, Phonepasong; Mattson, Mark P; Cutler, Roy G; Yu, Jack C; Stranahan, Alexis M

    2017-05-01

    Whole-body vibration (WBV) has gained attention as a potential exercise mimetic, but direct comparisons with the metabolic effects of exercise are scarce. To determine whether WBV recapitulates the metabolic and osteogenic effects of physical activity, we exposed male wild-type (WT) and leptin receptor-deficient (db/db) mice to daily treadmill exercise (TE) or WBV for 3 months. Body weights were analyzed and compared with WT and db/db mice that remained sedentary. Glucose and insulin tolerance testing revealed comparable attenuation of hyperglycemia and insulin resistance in db/db mice following TE or WBV. Both interventions reduced body weight in db/db mice and normalized muscle fiber diameter. TE or WBV also attenuated adipocyte hypertrophy in visceral adipose tissue and reduced hepatic lipid content in db/db mice. Although the effects of leptin receptor deficiency on cortical bone structure were not eliminated by either intervention, exercise and WBV increased circulating levels of osteocalcin in db/db mice. In the context of increased serum osteocalcin, the modest effects of TE and WBV on bone geometry, mineralization, and biomechanics may reflect subtle increases in osteoblast activity in multiple areas of the skeleton. Taken together, these observations indicate that WBV recapitulates the effects of exercise on metabolism in type 2 diabetes.

  16. Human Skin Constructs with Spatially Controlled Vasculature Using Primary and iPSC-Derived Endothelial Cells.

    Science.gov (United States)

    Abaci, Hasan E; Guo, Zongyou; Coffman, Abigail; Gillette, Brian; Lee, Wen-Han; Sia, Samuel K; Christiano, Angela M

    2016-07-01

    Vascularization of engineered human skin constructs is crucial for recapitulation of systemic drug delivery and for their long-term survival, functionality, and viable engraftment. In this study, the latest microfabrication techniques are used and a novel bioengineering approach is established to micropattern spatially controlled and perfusable vascular networks in 3D human skin equivalents using both primary and induced pluripotent stem cell (iPSC)-derived endothelial cells. Using 3D printing technology makes it possible to control the geometry of the micropatterned vascular networks. It is verified that vascularized human skin equivalents (vHSEs) can form a robust epidermis and establish an endothelial barrier function, which allows for the recapitulation of both topical and systemic delivery of drugs. In addition, the therapeutic potential of vHSEs for cutaneous wounds on immunodeficient mice is examined and it is demonstrated that vHSEs can both promote and guide neovascularization during wound healing. Overall, this innovative bioengineering approach can enable in vitro evaluation of topical and systemic drug delivery as well as improve the potential of engineered skin constructs to be used as a potential therapeutic option for the treatment of cutaneous wounds. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Maternal immune activation in rats produces temporal perception impairments in adult offspring analogous to those observed in schizophrenia.

    Directory of Open Access Journals (Sweden)

    Ashley R Deane

    Full Text Available The neurophysiology underlying temporal perception significantly overlaps with areas of dysfunction identified in schizophrenia. Patients commonly exhibit distorted temporal perception, which likely contributes to functional impairments. Thus, study of temporal perception in animal models of the disease may help to understand both cognitive and neurobiological factors involved in functional impairments in patients. As maternal immune activation (MIA has been shown to be a significant etiological risk factor in development of schizophrenia and other developmental psychiatric diseases, we tested interval timing in a rat model of MIA that has previously been shown to recapitulate several behavioural and neurophysiological impairments observed in the disease. Rats were tested on a temporal-bisection task, in which temporal duration stimuli were categorized as either "short" or "long" by responding to a corresponding lever. Data from this task were modeled to provide estimates of accuracy and sensitivity of temporal perception. Parameter estimates derived from the model fitting showed that MIA rats significantly overestimated the passage of time compared to controls. These results indicate that the MIA rat paradigm recapitulates timing distortions that are phenotypical of schizophrenia. These findings lend further support to the epidemiological validity of this MIA rat model, supporting its relevance for future research into the role of maternal immune activation in producing neurobiological and behavioural impairments in schizophrenia.

  18. Developing better mouse models to study cisplatin-induced kidney injury.

    Science.gov (United States)

    Sharp, Cierra N; Siskind, Leah J

    2017-10-01

    Cisplatin is a potent chemotherapeutic used for the treatment of many types of cancer. However, its dose-limiting side effect is nephrotoxicity leading to acute kidney injury (AKI). Patients who develop AKI have an increased risk of mortality and are more likely to develop chronic kidney disease (CKD). Unfortunately, there are no therapeutic interventions for the treatment of AKI. It has been suggested that the lack of therapies is due in part to the fact that the established mouse model used to study cisplatin-induced AKI does not recapitulate the cisplatin dosing regimen patients receive. In recent years, work has been done to develop more clinically relevant models of cisplatin-induced kidney injury, with much work focusing on incorporation of multiple low doses of cisplatin administered over a period of weeks. These models can be used to recapitulate the development of CKD after AKI and, by doing so, increase the likelihood of identifying novel therapeutic targets for the treatment of cisplatin-induced kidney injury. Copyright © 2017 the American Physiological Society.

  19. Induction of superficial cortical layer neurons from mouse embryonic stem cells by valproic acid.

    Science.gov (United States)

    Juliandi, Berry; Abematsu, Masahiko; Sanosaka, Tsukasa; Tsujimura, Keita; Smith, Austin; Nakashima, Kinichi

    2012-01-01

    Within the developing mammalian cortex, neural progenitors first generate deep-layer neurons and subsequently more superficial-layer neurons, in an inside-out manner. It has been reported recently that mouse embryonic stem cells (mESCs) can, to some extent, recapitulate cortical development in vitro, with the sequential appearance of neurogenesis markers resembling that in the developing cortex. However, mESCs can only recapitulate early corticogenesis; superficial-layer neurons, which are normally produced in later developmental periods in vivo, are under-represented. This failure of mESCs to reproduce later corticogenesis in vitro implies the existence of crucial factor(s) that are absent or uninduced in existing culture systems. Here we show that mESCs can give rise to superficial-layer neurons efficiently when treated with valproic acid (VPA), a histone deacetylase inhibitor. VPA treatment increased the production of Cux1-positive superficial-layer neurons, and decreased that of Ctip2-positive deep-layer neurons. These results shed new light on the mechanisms of later corticogenesis. Copyright © 2011 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  20. Three-Dimensional In Vitro Skin and Skin Cancer Models Based on Human Fibroblast-Derived Matrix.

    Science.gov (United States)

    Berning, Manuel; Prätzel-Wunder, Silke; Bickenbach, Jackie R; Boukamp, Petra

    2015-09-01

    Three-dimensional in vitro skin and skin cancer models help to dissect epidermal-dermal and tumor-stroma interactions. In the model presented here, normal human dermal fibroblasts isolated from adult skin self-assembled into dermal equivalents with their specific fibroblast-derived matrix (fdmDE) over 4 weeks. The fdmDE represented a complex human extracellular matrix that was stabilized by its own heterogeneous collagen fiber meshwork, largely resembling a human dermal in vivo architecture. Complemented with normal human epidermal keratinocytes, the skin equivalent (fdmSE) thereof favored the establishment of a well-stratified and differentiated epidermis and importantly allowed epidermal regeneration in vitro for at least 24 weeks. Moreover, the fdmDE could be used to study the features of cutaneous skin cancer. Complementing fdmDE with HaCaT cells in different stages of malignancy or tumor-derived cutaneous squamous cell carcinoma cell lines, the resulting skin cancer equivalents (fdmSCEs) recapitulated the respective degree of tumorigenicity. In addition, the fdmSCE invasion phenotypes correlated with their individual degree of tissue organization, disturbance in basement membrane organization, and presence of matrix metalloproteinases. Together, fdmDE-based models are well suited for long-term regeneration of normal human epidermis and, as they recapitulate tumor-specific growth, differentiation, and invasion profiles of cutaneous skin cancer cells, also provide an excellent human in vitro skin cancer model.

  1. A reproducible brain tumour model established from human glioblastoma biopsies

    International Nuclear Information System (INIS)

    Wang, Jian; Chekenya, Martha; Bjerkvig, Rolf; Enger, Per Ø; Miletic, Hrvoje; Sakariassen, Per Ø; Huszthy, Peter C; Jacobsen, Hege; Brekkå, Narve; Li, Xingang; Zhao, Peng; Mørk, Sverre

    2009-01-01

    Establishing clinically relevant animal models of glioblastoma multiforme (GBM) remains a challenge, and many commonly used cell line-based models do not recapitulate the invasive growth patterns of patient GBMs. Previously, we have reported the formation of highly invasive tumour xenografts in nude rats from human GBMs. However, implementing tumour models based on primary tissue requires that these models can be sufficiently standardised with consistently high take rates. In this work, we collected data on growth kinetics from a material of 29 biopsies xenografted in nude rats, and characterised this model with an emphasis on neuropathological and radiological features. The tumour take rate for xenografted GBM biopsies were 96% and remained close to 100% at subsequent passages in vivo, whereas only one of four lower grade tumours engrafted. Average time from transplantation to the onset of symptoms was 125 days ± 11.5 SEM. Histologically, the primary xenografts recapitulated the invasive features of the parent tumours while endothelial cell proliferations and necrosis were mostly absent. After 4-5 in vivo passages, the tumours became more vascular with necrotic areas, but also appeared more circumscribed. MRI typically revealed changes related to tumour growth, several months prior to the onset of symptoms. In vivo passaging of patient GBM biopsies produced tumours representative of the patient tumours, with high take rates and a reproducible disease course. The model provides combinations of angiogenic and invasive phenotypes and represents a good alternative to in vitro propagated cell lines for dissecting mechanisms of brain tumour progression

  2. Epstein–Barr virus glycoprotein gM can interact with the cellular protein p32 and knockdown of p32 impairs virus

    Energy Technology Data Exchange (ETDEWEB)

    Changotra, Harish; Turk, Susan M. [Department of Microbiology and Immunology, Center for Molecular and Tumor Virology and Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Artigues, Antonio [Department of Biochemistry, University of Kansas Medical Center, Kansas City, KS (United States); Thakur, Nagendra; Gore, Mindy; Muggeridge, Martin I. [Department of Microbiology and Immunology, Center for Molecular and Tumor Virology and Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Hutt-Fletcher, Lindsey M., E-mail: lhuttf@lsuhsc.edu [Department of Microbiology and Immunology, Center for Molecular and Tumor Virology and Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, LA (United States)

    2016-02-15

    The Epstein–Barr virus glycoprotein complex gMgN has been implicated in assembly and release of fully enveloped virus, although the precise role that it plays has not been elucidated. We report here that the long predicted cytoplasmic tail of gM is not required for complex formation and that it interacts with the cellular protein p32, which has been reported to be involved in nuclear egress of human cytomegalovirus and herpes simplex virus. Although redistribution of p32 and colocalization with gM was not observed in virus infected cells, knockdown of p32 expression by siRNA or lentivirus-delivered shRNA recapitulated the phenotype of a virus lacking expression of gNgM. A proportion of virus released from cells sedimented with characteristics of virus lacking an intact envelope and there was an increase in virus trapped in nuclear condensed chromatin. The observations suggest the possibility that p32 may also be involved in nuclear egress of Epstein–Barr virus. - Highlights: • The predicted cytoplasmic tail of gM is not required to complex with gN. • Cellular p32 can interact with the predicted cytoplasmic tail of EBV gM. • Knockdown of p32 recapitulates the phenotype of virus lacking the gNgM complex.

  3. Small Animal Models for Evaluating Filovirus Countermeasures.

    Science.gov (United States)

    Banadyga, Logan; Wong, Gary; Qiu, Xiangguo

    2018-05-11

    The development of novel therapeutics and vaccines to treat or prevent disease caused by filoviruses, such as Ebola and Marburg viruses, depends on the availability of animal models that faithfully recapitulate clinical hallmarks of disease as it is observed in humans. In particular, small animal models (such as mice and guinea pigs) are historically and frequently used for the primary evaluation of antiviral countermeasures, prior to testing in nonhuman primates, which represent the gold-standard filovirus animal model. In the past several years, however, the filovirus field has witnessed the continued refinement of the mouse and guinea pig models of disease, as well as the introduction of the hamster and ferret models. We now have small animal models for most human-pathogenic filoviruses, many of which are susceptible to wild type virus and demonstrate key features of disease, including robust virus replication, coagulopathy, and immune system dysfunction. Although none of these small animal model systems perfectly recapitulates Ebola virus disease or Marburg virus disease on its own, collectively they offer a nearly complete set of tools in which to carry out the preclinical development of novel antiviral drugs.

  4. Ontogeny of the vertebral column of Eleutherodactylus johnstonei (Anura: Eleutherodactylidae) reveals heterochronies relative to metamorphic frogs.

    Science.gov (United States)

    Meza-Joya, Fabio Leonardo; Ramos-Pallares, Eliana Patricia; Ramírez-Pinilla, Martha Patricia

    2013-07-01

    Over the last century, the morphogenesis of the vertebral column has been considered as a highly conserved process among anurans. This statement is based on the study of few metamorphic taxa, ignoring the role of developmental mechanisms underlying the evolution of specialized life-histories. Direct development in anurans has been regarded as evolutionarily derived and involves developmental recapitulation and repatterning at different levels in all amphibian taxa studied so far. Herein, we analyze the vertebral column morphogenesis of the direct-developing frog Eleutherodactylus johnstonei, describing the sequence of chondrification and ossification, based on cleared and double-stained specimens from early stage embryos to adults. In general, our results show that the morphogenesis of the vertebral column in E. johnstonei recapitulates the ancestral tadpole-like pattern of development. However, the analysis of the sequence of events using heterochrony plots shows important heterocronies relative to metamorphic species, such as a delay in the chondrification of the vertebral centra and in osteogenesis. These ontogenetic peculiarities may represent derived traits in direct-developing frogs and are possibly correlated with its unusual life history. In addition, several features of the vertebral column of E. johnstonei are highly variable from its typical morphology. We report some malformations and small deviations, which do not seem to affect the survival of individuals. These anomalies have also been found in other frogs, and include many vertebral defects, such as vertebral fusion, and vertebral preclusion and/or induction. Copyright © 2013 Wiley Periodicals, Inc.

  5. Adenovirus Protein E4-ORF1 Activation of PI3 Kinase Reveals Differential Regulation of Downstream Effector Pathways in Adipocytes.

    Science.gov (United States)

    Chaudhary, Natasha; Gonzalez, Eva; Chang, Sung-Hee; Geng, Fuqiang; Rafii, Shahin; Altorki, Nasser K; McGraw, Timothy E

    2016-12-20

    Insulin activation of phosphatidylinositol 3-kinase (PI3K) regulates metabolism, including the translocation of the Glut4 glucose transporter to the plasma membrane and inactivation of the FoxO1 transcription factor. Adenoviral protein E4-ORF1 stimulates cellular glucose metabolism by mimicking growth-factor activation of PI3K. We have used E4-ORF1 as a tool to dissect PI3K-mediated signaling in adipocytes. E4-ORF1 activation of PI3K in adipocytes recapitulates insulin regulation of FoxO1 but not regulation of Glut4. This uncoupling of PI3K effects occurs despite E4-ORF1 activating PI3K and downstream signaling to levels achieved by insulin. Although E4-ORF1 does not fully recapitulate insulin's effects on Glut4, it enhances insulin-stimulated insertion of Glut4-containing vesicles to the plasma membrane independent of Rab10, a key regulator of Glut4 trafficking. E4-ORF1 also stimulates plasma membrane translocation of ubiquitously expressed Glut1 glucose transporter, an effect that is likely essential for E4-ORF1 to promote an anabolic metabolism in a broad range of cell types. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  6. Adenovirus Protein E4-ORF1 Activation of PI3 Kinase Reveals Differential Regulation of Downstream Effector Pathways in Adipocytes

    Directory of Open Access Journals (Sweden)

    Natasha Chaudhary

    2016-12-01

    Full Text Available Insulin activation of phosphatidylinositol 3-kinase (PI3K regulates metabolism, including the translocation of the Glut4 glucose transporter to the plasma membrane and inactivation of the FoxO1 transcription factor. Adenoviral protein E4-ORF1 stimulates cellular glucose metabolism by mimicking growth-factor activation of PI3K. We have used E4-ORF1 as a tool to dissect PI3K-mediated signaling in adipocytes. E4-ORF1 activation of PI3K in adipocytes recapitulates insulin regulation of FoxO1 but not regulation of Glut4. This uncoupling of PI3K effects occurs despite E4-ORF1 activating PI3K and downstream signaling to levels achieved by insulin. Although E4-ORF1 does not fully recapitulate insulin’s effects on Glut4, it enhances insulin-stimulated insertion of Glut4-containing vesicles to the plasma membrane independent of Rab10, a key regulator of Glut4 trafficking. E4-ORF1 also stimulates plasma membrane translocation of ubiquitously expressed Glut1 glucose transporter, an effect that is likely essential for E4-ORF1 to promote an anabolic metabolism in a broad range of cell types.

  7. Energy utilization of induced pluripotent stem cell-derived cardiomyocyte in Fabry disease.

    Science.gov (United States)

    Chou, Shih-Jie; Yu, Wen-Chung; Chang, Yuh-Lih; Chen, Wen-Yeh; Chang, Wei-Chao; Chien, Yueh; Yen, Jiin-Cherng; Liu, Yung-Yang; Chen, Shih-Jen; Wang, Chien-Ying; Chen, Yu-Han; Niu, Dau-Ming; Lin, Shing-Jong; Chen, Jaw-Wen; Chiou, Shih-Hwa; Leu, Hsin-Bang

    2017-04-01

    Fabry disease (FD) is a lysosomal storage disease in which glycosphingolipids (GB3) accumulate in organs of the human body, leading to idiopathic hypertrophic cardiomyopathy and target organ damage. Its pathophysiology is still poorly understood. We aimed to generate patient-specific induced pluripotent stem cells (iPSC) from FD patients presenting cardiomyopathy to determine whether the model could recapitulate key features of the disease phenotype and to investigate the energy metabolism in Fabry disease. Peripheral blood mononuclear cells from a 30-year-old Chinese man with a diagnosis of Fabry disease, GLA gene (IVS4+919G>A) mutation were reprogrammed into iPSCs and differentiated into iPSC-CMs and energy metabolism was analyzed in iPSC-CMs. The FD-iPSC-CMs recapitulated numerous aspects of the FD phenotype including reduced GLA activity, cellular hypertrophy, GB3 accumulation and impaired contractility. Decreased energy metabolism with energy utilization shift to glycolysis was observed, but the decreased energy metabolism was not modified by enzyme rescue replacement (ERT) in FD-iPSCs-CMs. This model provided a promising in vitro model for the investigation of the underlying disease mechanism and development of novel therapeutic strategies for FD. This potential remedy for enhancing the energetic network and utility efficiency warrants further study to identify novel therapies for the disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Distinct molecular subtypes of uterine leiomyosarcoma respond differently to chemotherapy treatment.

    Science.gov (United States)

    An, Yang; Wang, Shuzhen; Li, Songlin; Zhang, Lulu; Wang, Dayong; Wang, Haojie; Zhu, Shibai; Zhu, Wan; Li, Yongqiang; Chen, Wenwu; Ji, Shaoping; Guo, Xiangqian

    2017-09-11

    Uterine leiomyosarcoma (ULMS) is an aggressive form of soft tissue tumors. The molecular heterogeneity and pathogenesis of ULMS are not well understood. Expression profiling data were used to determine the possibility and optimal number of ULMS molecular subtypes. Next, clinicopathological characters and molecular pathways were analyzed in each subtype to prospect the clinical applications and progression mechanisms of ULMS. Two distinct molecular subtypes of ULMS were defined based on different gene expression signatures. Subtype I ULMS recapitulated low-grade ULMS, the gene expression pattern of which resembled normal smooth muscle cells, characterized by overexpression of smooth muscle function genes such as LMOD1, SLMAP, MYLK, MYH11. In contrast, subtype II ULMS recapitulated high-grade ULMS with higher tumor weight and invasion rate, and was characterized by overexpression of genes involved in the pathway of epithelial to mesenchymal transition and tumorigenesis, such as CDK6, MAPK13 and HOXA1. We identified two distinct molecular subtypes of ULMS responding differently to chemotherapy treatment. Our findings provide a better understanding of ULMS intrinsic molecular subtypes, and will potentially facilitate the development of subtype-specific diagnosis biomarkers and therapy strategies for these tumors.

  9. Medullary Thymic Epithelial Cells and Central Tolerance in Autoimmune Hepatitis Development: Novel Perspective from a New Mouse Model

    Directory of Open Access Journals (Sweden)

    Konstantina Alexandropoulos

    2015-01-01

    Full Text Available Autoimmune hepatitis (AIH is an immune-mediated disorder that affects the liver parenchyma. Diagnosis usually occurs at the later stages of the disease, complicating efforts towards understanding the causes of disease development. While animal models are useful for studying the etiology of autoimmune disorders, most of the existing animal models of AIH do not recapitulate the chronic course of the human condition. In addition, approaches to mimic AIH-associated liver inflammation have instead led to liver tolerance, consistent with the high tolerogenic capacity of the liver. Recently, we described a new mouse model that exhibited spontaneous and chronic liver inflammation that recapitulated the known histopathological and immunological parameters of AIH. The approach involved liver-extrinsic genetic engineering that interfered with the induction of T-cell tolerance in the thymus, the very process thought to inhibit AIH induction by liver-specific expression of exogenous antigens. The mutation led to depletion of specialized thymic epithelial cells that present self-antigens and eliminate autoreactive T-cells before they exit the thymus. Based on our findings, which are summarized below, we believe that this mouse model represents a relevant experimental tool towards elucidating the cellular and molecular aspects of AIH development and developing novel therapeutic strategies for treating this disease.

  10. Building an Anisotropic Meniscus with Zonal Variations

    Science.gov (United States)

    Higashioka, Michael M.; Chen, Justin A.; Hu, Jerry C.

    2014-01-01

    Toward addressing the difficult problems of knee meniscus regeneration, a self-assembling process has been used to re-create the native morphology and matrix properties. A significant problem in such attempts is the recapitulation of the distinct zones of the meniscus, the inner, more cartilaginous and the outer, more fibrocartilaginous zones. In this study, an anisotropic and zonally variant meniscus was produced by self-assembly of the inner meniscus (100% chondrocytes) followed by cell seeding the outer meniscus (coculture of chondrocytes and meniscus cells). After 4 weeks in culture, the engineered, inner meniscus exhibited a 42% increase in both instantaneous and relaxation moduli and a 62% increase in GAG/DW, as compared to the outer meniscus. In contrast, the circumferential tensile modulus and collagen/DW of the outer zone was 101% and 129% higher, respectively, than the values measured for the inner zone. Furthermore, there was no difference in the radial tensile modulus between the control and zonal engineered menisci, suggesting that the inner and outer zones of the engineered zonal menisci successfully integrated. These data demonstrate that not only can biomechanical and biochemical properties be engineered to differ by the zone, but they can also recapitulate the anisotropic behavior of the knee meniscus. PMID:23931258

  11. Establishment and Characterization of UTI and CAUTI in a Mouse Model.

    Science.gov (United States)

    Conover, Matt S; Flores-Mireles, Ana L; Hibbing, Michael E; Dodson, Karen; Hultgren, Scott J

    2015-06-23

    Urinary tract infections (UTI) are highly prevalent, a significant cause of morbidity and are increasingly resistant to treatment with antibiotics. Females are disproportionately afflicted by UTI: 50% of all women will have a UTI in their lifetime. Additionally, 20-40% of these women who have an initial UTI will suffer a recurrence with some suffering frequent recurrences with serious deterioration in the quality of life, pain and discomfort, disruption of daily activities, increased healthcare costs, and few treatment options other than long-term antibiotic prophylaxis. Uropathogenic Escherichia coli (UPEC) is the primary causative agent of community acquired UTI. Catheter-associated UTI (CAUTI) is the most common hospital acquired infection accounting for a million occurrences in the US annually and dramatic healthcare costs. While UPEC is also the primary cause of CAUTI, other causative agents are of increased significance including Enterococcus faecalis. Here we utilize two well-established mouse models that recapitulate many of the clinical characteristics of these human diseases. For UTI, a C3H/HeN model recapitulates many of the features of UPEC virulence observed in humans including host responses, IBC formation and filamentation. For CAUTI, a model using C57BL/6 mice, which retain catheter bladder implants, has been shown to be susceptible to E. faecalis bladder infection. These representative models are being used to gain striking new insights into the pathogenesis of UTI disease, which is leading to the development of novel therapeutics and management or prevention strategies.

  12. Progress in Development of Improved Ion-Channel Biosensors

    Science.gov (United States)

    Nadeau, Jay L.; White, Victor E.; Maurer, Joshua A.; Dougherty, Dennis A.

    2008-01-01

    Further improvements have recently been made in the development of the devices described in Improved Ion-Channel Biosensors (NPO-30710), NASA Tech Briefs, Vol. 28, No. 10 (October 2004), page 30. As discussed in more detail in that article, these sensors offer advantages of greater stability, greater lifetime, and individual electrical addressability, relative to prior ion-channel biosensors. In order to give meaning to a brief description of the recent improvements, it is necessary to recapitulate a substantial portion of the text of the cited previous article. The figure depicts one sensor that incorporates the recent improvements, and can be helpful in understanding the recapitulated text, which follows: These sensors are microfabricated from silicon and other materials compatible with silicon. Typically, the sensors are fabricated in arrays in silicon wafers on glass plates. Each sensor in the array can be individually electrically addressed, without interference with its neighbors. Each sensor includes a well covered by a thin layer of silicon nitride, in which is made a pinhole for the formation of a lipid bilayer membrane. In one stage of fabrication, the lower half of the well is filled with agarose, which is allowed to harden. Then the upper half of the well is filled with a liquid electrolyte (which thereafter remains liquid) and a lipid bilayer is painted over the pinhole. The liquid contains a protein that forms an ion channel on top of the hardened agarose. The combination of enclosure in the well and support by the hardened agarose provides the stability needed to keep the membrane functional for times as long as days or even weeks. An electrode above the well, another electrode below the well, and all the materials between the electrodes together constitute a capacitor. What is measured is the capacitive transient current in response to an applied voltage pulse. One notable feature of this sensor, in comparison with prior such sensors, is a

  13. Functional Gene Discovery and Characterization of Genes and Alleles Affecting Wood Biomass Yield and Quality in Populus

    Energy Technology Data Exchange (ETDEWEB)

    Busov, Victor [Michigan Technological Univ., Houghton, MI (United States)

    2017-02-12

    Adoption of biofuels as economically and environmentally viable alternative to fossil fuels would require development of specialized bioenergy varieties. A major goal in the breeding of such varieties is the improvement of lignocellulosic biomass yield and quality. These are complex traits and understanding the underpinning molecular mechanism can assist and accelerate their improvement. This is particularly important for tree bioenergy crops like poplars (species and hybrids from the genus Populus), for which breeding progress is extremely slow due to long generation cycles. A variety of approaches have been already undertaken to better understand the molecular bases of biomass yield and quality in poplar. An obvious void in these undertakings has been the application of mutagenesis. Mutagenesis has been instrumental in the discovery and characterization of many plant traits including such that affect biomass yield and quality. In this proposal we use activation tagging to discover genes that can significantly affect biomass associated traits directly in poplar, a premier bioenergy crop. We screened a population of 5,000 independent poplar activation tagging lines under greenhouse conditions for a battery of biomass yield traits. These same plants were then analyzed for changes in wood chemistry using pyMBMS. As a result of these screens we have identified nearly 800 mutants, which are significantly (P<0.05) different when compared to wild type. Of these majority (~700) are affected in one of ten different biomass yield traits and 100 in biomass quality traits (e.g., lignin, S/G ration and C6/C5 sugars). We successfully recovered the position of the tag in approximately 130 lines, showed activation in nearly half of them and performed recapitulation experiments with 20 genes prioritized by the significance of the phenotype. Recapitulation experiments are still ongoing for many of the genes but the results are encouraging. For example, we have shown successful

  14. Enhanced nutrient transport improves the depth-dependent properties of tri-layered engineered cartilage constructs with zonal co-culture of chondrocytes and MSCs.

    Science.gov (United States)

    Kim, Minwook; Farrell, Megan J; Steinberg, David R; Burdick, Jason A; Mauck, Robert L

    2017-08-01

    Biomimetic design in cartilage tissue engineering is a challenge given the complexity of the native tissue. While numerous studies have generated constructs with near-native bulk properties, recapitulating the depth-dependent features of native tissue remains a challenge. Furthermore, limitations in nutrient transport and matrix accumulation in engineered constructs hinders maturation within the central core of large constructs. To overcome these limitations, we fabricated tri-layered constructs that recapitulate the depth-dependent cellular organization and functional properties of native tissue using zonally derived chondrocytes co-cultured with MSCs. We also introduced porous hollow fibers (HFs) and HFs/cotton threads to enhance nutrient transport. Our results showed that tri-layered constructs with depth-dependent organization and properties could be fabricated. The addition of HFs or HFs/threads improved matrix accumulation in the central core region. With HF/threads, the local modulus in the deep region of tri-layered constructs nearly matched that of native tissue, though the properties in the central regions remained lower. These constructs reproduced the zonal organization and depth-dependent properties of native tissue, and demonstrate that a layer-by-layer fabrication scheme holds promise for the biomimetic repair of focal cartilage defects. Articular cartilage is a highly organized tissue driven by zonal heterogeneity of cells, extracellular matrix proteins and fibril orientations, resulting in depth-dependent mechanical properties. Therefore, the recapitulation of the functional properties of native cartilage in a tissue engineered construct requires such a biomimetic design of the morphological organization, and this has remained a challenge in cartilage tissue engineering. This study demonstrates that a layer-by-layer fabrication scheme, including co-cultures of zone-specific articular CHs and MSCs, can reproduce the depth-dependent characteristics

  15. Key Inflammatory Processes in Human NASH Are Reflected in Ldlr-/-.Leiden Mice: A Translational Gene Profiling Study.

    Science.gov (United States)

    Morrison, Martine C; Kleemann, Robert; van Koppen, Arianne; Hanemaaijer, Roeland; Verschuren, Lars

    2018-01-01

    Introduction: It is generally accepted that metabolic inflammation in the liver is an important driver of disease progression in NASH and associated matrix remodeling/fibrosis. However, the exact molecular inflammatory mechanisms are poorly defined in human studies. Investigation of key pathogenic mechanisms requires the use of pre-clinical models, for instance for time-resolved studies. Such models must reflect molecular disease processes of importance in patients. Herein we characterized inflammation in NASH patients on the molecular level by transcriptomics and investigated whether key human disease pathways can be recapitulated experimentally in Ldlr -/- .Leiden mice, an established pre-clinical model of NASH. Methods: Human molecular inflammatory processes were defined using a publicly available NASH gene expression profiling dataset (GSE48452) allowing the comparison of biopsy-confirmed NASH patients with normal controls. Gene profiling data from high-fat diet (HFD)-fed Ldlr -/- .Leiden mice (GSE109345) were used for assessment of the translational value of these mice. Results: In human NASH livers, we observed regulation of 65 canonical pathways of which the majority was involved in inflammation (32%), lipid metabolism (16%), and extracellular matrix/remodeling (12%). A similar distribution of pathways across these categories, inflammation (36%), lipid metabolism (24%) and extracellular matrix/remodeling (8%) was observed in HFD-fed Ldlr -/- .Leiden mice. Detailed evaluation of these pathways revealed that a substantial proportion (11 out of 13) of human NASH inflammatory pathways was recapitulated in Ldlr -/- .Leiden mice. Furthermore, the activation state of identified master regulators of inflammation (i.e., specific transcription factors, cytokines, and growth factors) in human NASH was largely reflected in Ldlr -/- .Leiden mice, further substantiating its translational value. Conclusion: Human NASH is characterized by upregulation of specific

  16. Key Inflammatory Processes in Human NASH Are Reflected in Ldlr−/−.Leiden Mice: A Translational Gene Profiling Study

    Science.gov (United States)

    Morrison, Martine C.; Kleemann, Robert; van Koppen, Arianne; Hanemaaijer, Roeland; Verschuren, Lars

    2018-01-01

    Introduction: It is generally accepted that metabolic inflammation in the liver is an important driver of disease progression in NASH and associated matrix remodeling/fibrosis. However, the exact molecular inflammatory mechanisms are poorly defined in human studies. Investigation of key pathogenic mechanisms requires the use of pre-clinical models, for instance for time-resolved studies. Such models must reflect molecular disease processes of importance in patients. Herein we characterized inflammation in NASH patients on the molecular level by transcriptomics and investigated whether key human disease pathways can be recapitulated experimentally in Ldlr−/−.Leiden mice, an established pre-clinical model of NASH. Methods: Human molecular inflammatory processes were defined using a publicly available NASH gene expression profiling dataset (GSE48452) allowing the comparison of biopsy-confirmed NASH patients with normal controls. Gene profiling data from high-fat diet (HFD)-fed Ldlr−/−.Leiden mice (GSE109345) were used for assessment of the translational value of these mice. Results: In human NASH livers, we observed regulation of 65 canonical pathways of which the majority was involved in inflammation (32%), lipid metabolism (16%), and extracellular matrix/remodeling (12%). A similar distribution of pathways across these categories, inflammation (36%), lipid metabolism (24%) and extracellular matrix/remodeling (8%) was observed in HFD-fed Ldlr−/−.Leiden mice. Detailed evaluation of these pathways revealed that a substantial proportion (11 out of 13) of human NASH inflammatory pathways was recapitulated in Ldlr−/−.Leiden mice. Furthermore, the activation state of identified master regulators of inflammation (i.e., specific transcription factors, cytokines, and growth factors) in human NASH was largely reflected in Ldlr−/−.Leiden mice, further substantiating its translational value. Conclusion: Human NASH is characterized by upregulation of specific

  17. Patterning biomaterials for the spatiotemporal delivery of bioactive molecules

    Directory of Open Access Journals (Sweden)

    Silvia eMinardi

    2016-06-01

    Full Text Available The aim of tissue engineering is to promote the repair of functional tissues. For decades, the combined use of biomaterials, growth factors, and stem cells has been at the base of several regeneration strategies. Among these, biomimicry emerged as a robust strategy to efficiently address this clinical challenge. Biomimetic materials, able to recapitulate the composition and architecture of the extracellular matrix, are the materials of choice, for their biocompatibility and higher rate of efficacy. In addition, it has become increasingly clear that restoring the complex biochemical environment of the target tissue is crucial for its regeneration. Towards this aim, the combination of scaffolds and growth factors is required. The advent of nanotechnology significantly impacted the field of tissue engineering by providing new ways to reproduce the complex spatial and temporal biochemical patterns of tissues. This review will present the most recent approaches to finely control the spatiotemporal release of bioactive molecules for various tissue engineering applications.

  18. Microengineered physiological biomimicry: organs-on-chips.

    Science.gov (United States)

    Huh, Dongeun; Torisawa, Yu-suke; Hamilton, Geraldine A; Kim, Hyun Jung; Ingber, Donald E

    2012-06-21

    Microscale engineering technologies provide unprecedented opportunities to create cell culture microenvironments that go beyond current three-dimensional in vitro models by recapitulating the critical tissue-tissue interfaces, spatiotemporal chemical gradients, and dynamic mechanical microenvironments of living organs. Here we review recent advances in this field made over the past two years that are focused on the development of 'Organs-on-Chips' in which living cells are cultured within microfluidic devices that have been microengineered to reconstitute tissue arrangements observed in living organs in order to study physiology in an organ-specific context and to develop specialized in vitro disease models. We discuss the potential of organs-on-chips as alternatives to conventional cell culture models and animal testing for pharmaceutical and toxicology applications. We also explore challenges that lie ahead if this field is to fulfil its promise to transform the future of drug development and chemical safety testing.

  19. Promoter proximal polyadenylation sites reduce transcription activity

    DEFF Research Database (Denmark)

    Andersen, Pia Kjølhede; Lykke-Andersen, Søren; Jensen, Torben Heick

    2012-01-01

    Gene expression relies on the functional communication between mRNA processing and transcription. We previously described the negative impact of a point-mutated splice donor (SD) site on transcription. Here we demonstrate that this mutation activates an upstream cryptic polyadenylation (CpA) site......, which in turn causes reduced transcription. Functional depletion of U1 snRNP in the context of the wild-type SD triggers the same CpA event accompanied by decreased RNA levels. Thus, in accordance with recent findings, U1 snRNP can shield premature pA sites. The negative impact of unshielded pA sites...... on transcription requires promoter proximity, as demonstrated using artificial constructs and supported by a genome-wide data set. Importantly, transcription down-regulation can be recapitulated in a gene context devoid of splice sites by placing a functional bona fide pA site/transcription terminator within ∼500...

  20. A focus on reward in anorexia nervosa through the lens of the activity-based anorexia rodent model.

    Science.gov (United States)

    Foldi, C J; Milton, L K; Oldfield, B J

    2017-10-01

    Patients suffering anorexia nervosa (AN) become anhedonic, unable or unwilling to derive normal pleasures and tend to avoid rewarding outcomes, most profoundly in food intake. The activity-based anorexia model recapitulates many of the pathophysiological and behavioural hallmarks of the human condition, including a reduction in food intake, excessive exercise, dramatic weight loss, loss of reproductive cycles, hypothermia and anhedonia, and therefore it allows investigation into the underlying neurobiology of anorexia nervosa. The use of this model has directed attention to disruptions in central reward neurocircuitry, which may contribute to disease susceptibility. The purpose of this review is to demonstrate the utility of this unique model to provide insight into the mechanisms of reward relevant to feeding and weight loss, which may ultimately help to unravel the neurobiology of anorexia nervosa and, in a broader sense, the foundation of reward-based feeding. © 2017 British Society for Neuroendocrinology.

  1. Review Paper: A Review on Brain Stimulation Using Low Intensity Focused Ultrasound

    Directory of Open Access Journals (Sweden)

    Ehsan Rezayat

    2016-07-01

    Full Text Available Brain stimulation techniques are important in both basic and clinical studies. Majority of well-known brain stimulating techniques have low spatial resolution or entail invasive processes. Low intensity focused ultrasound (LIFU seems to be a proper candidate for dealing with such deficiencies. This review recapitulates studies which explored the effects of LIFU on brain structures and its function, in both research and clinical areas. Although the mechanism of LIFU action is still unclear, its different effects from molecular level up to behavioral level can be explored in animal and human brain. It can also be coupled with brain imaging assessments in future research.

  2. In situ imaging and proteome profiling indicate andrographolide is a highly promiscuous compound

    Science.gov (United States)

    Li, Lin; Wijaya, Hadhi; Samanta, Sanjay; Lam, Yulin; Yao, Shao Q.

    2015-06-01

    Natural products represent an enormous source of pharmacologically useful compounds, and are often used as the starting point in modern drug discovery. Many biologically interesting natural products are however not being pursued as potential drug candidates, partly due to a lack of well-defined mechanism-of-action. Traditional in vitro methods for target identification of natural products based on affinity protein enrichment from crude cellular lysates cannot faithfully recapitulate protein-drug interactions in living cells. Reported herein are dual-purpose probes inspired by the natural product andrographolide, capable of both reaction-based, real-time bioimaging and in situ proteome profiling/target identification in live mammalian cells. Our results confirm that andrographolide is a highly promiscuous compound and engaged in covalent interactions with numerous previously unknown cellular targets in cell type-specific manner. We caution its potential therapeutic effects should be further investigated in detail.

  3. Marketing strategies nurses can employ to promote health.

    Science.gov (United States)

    McCormack, D

    1994-01-01

    Marketing strategies are employed to ensure the success of new products, services or programs. Both profit and non-profit organizations have used social marketing strategies to inform, to motivate interest, and to engage the involvement of the consumer. A client-dependent health care system did not find it necessary to market services, but a health care system that encourages clients to choose the most appropriate health promotion service available must market services. Nurses are in the business of promoting the health of clients. Therefore, it is essential that nurses become familiar with, and involved in, the development of marketing plans and strategies. The connection between the four variables of the marketing mix (product, promotion, place, and price) and promoting the health of clients is described. A case example recapitulating the marketing strategies employed to raise public awareness of a self-help group for family caregivers is related, the marketing response is evaluated, and future recommendations are proposed.

  4. Bioprinted three dimensional human tissues for toxicology and disease modeling.

    Science.gov (United States)

    Nguyen, Deborah G; Pentoney, Stephen L

    2017-03-01

    The high rate of attrition among clinical-stage therapies, due largely to an inability to predict human toxicity and/or efficacy, underscores the need for in vitro models that better recapitulate in vivo human biology. In much the same way that additive manufacturing has revolutionized the production of solid objects, three-dimensional (3D) bioprinting is enabling the automated production of more architecturally and functionally accurate in vitro tissue culture models. Here, we provide an overview of the most commonly used bioprinting approaches and how they are being used to generate complex in vitro tissues for use in toxicology and disease modeling research. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Dentate gyrus mossy cells control spontaneous convulsive seizures and spatial memory.

    Science.gov (United States)

    Bui, Anh D; Nguyen, Theresa M; Limouse, Charles; Kim, Hannah K; Szabo, Gergely G; Felong, Sylwia; Maroso, Mattia; Soltesz, Ivan

    2018-02-16

    Temporal lobe epilepsy (TLE) is characterized by debilitating, recurring seizures and an increased risk for cognitive deficits. Mossy cells (MCs) are key neurons in the hippocampal excitatory circuit, and the partial loss of MCs is a major hallmark of TLE. We investigated how MCs contribute to spontaneous ictal activity and to spatial contextual memory in a mouse model of TLE with hippocampal sclerosis, using a combination of optogenetic, electrophysiological, and behavioral approaches. In chronically epileptic mice, real-time optogenetic modulation of MCs during spontaneous hippocampal seizures controlled the progression of activity from an electrographic to convulsive seizure. Decreased MC activity is sufficient to impede encoding of spatial context, recapitulating observed cognitive deficits in chronically epileptic mice. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  6. Organotypic Cultures as a Model to Study Adult Neurogenesis in CNS Disorders

    Directory of Open Access Journals (Sweden)

    Fabio Cavaliere

    2016-01-01

    Full Text Available Neural regeneration resides in certain specific regions of adult CNS. Adult neurogenesis occurs throughout life, especially from the subgranular zone of hippocampus and the subventricular zone, and can be modulated in physiological and pathological conditions. Numerous techniques and animal models have been developed to demonstrate and observe neural regeneration but, in order to study the molecular and cellular mechanisms and to characterize multiple types of cell populations involved in the activation of neurogenesis and gliogenesis, investigators have to turn to in vitro models. Organotypic cultures best recapitulate the 3D organization of the CNS and can be explored taking advantage of many techniques. Here, we review the use of organotypic cultures as a reliable and well defined method to study the mechanisms of neurogenesis under normal and pathological conditions. As an example, we will focus on the possibilities these cultures offer to study the pathophysiology of diseases like Alzheimer disease, Parkinson’s disease, and cerebral ischemia.

  7. ALFY-Controlled DVL3 Autophagy Regulates Wnt Signaling, Determining Human Brain Size.

    Directory of Open Access Journals (Sweden)

    Rotem Kadir

    2016-03-01

    Full Text Available Primary microcephaly is a congenital neurodevelopmental disorder of reduced head circumference and brain volume, with fewer neurons in the cortex of the developing brain due to premature transition between symmetrical and asymmetrical cellular division of the neuronal stem cell layer during neurogenesis. We now show through linkage analysis and whole exome sequencing, that a dominant mutation in ALFY, encoding an autophagy scaffold protein, causes human primary microcephaly. We demonstrate the dominant effect of the mutation in drosophila: transgenic flies harboring the human mutant allele display small brain volume, recapitulating the disease phenotype. Moreover, eye-specific expression of human mutant ALFY causes rough eye phenotype. In molecular terms, we demonstrate that normally ALFY attenuates the canonical Wnt signaling pathway via autophagy-dependent removal specifically of aggregates of DVL3 and not of Dvl1 or Dvl2. Thus, autophagic attenuation of Wnt signaling through removal of Dvl3 aggregates by ALFY acts in determining human brain size.

  8. Bidirectional Interplay between Vimentin Intermediate Filaments and Contractile Actin Stress Fibers

    Directory of Open Access Journals (Sweden)

    Yaming Jiu

    2015-06-01

    Full Text Available The actin cytoskeleton and cytoplasmic intermediate filaments contribute to cell migration and morphogenesis, but the interplay between these two central cytoskeletal elements has remained elusive. Here, we find that specific actin stress fiber structures, transverse arcs, interact with vimentin intermediate filaments and promote their retrograde flow. Consequently, myosin-II-containing arcs are important for perinuclear localization of the vimentin network in cells. The vimentin network reciprocally restricts retrograde movement of arcs and hence controls the width of flat lamellum at the leading edge of the cell. Depletion of plectin recapitulates the vimentin organization phenotype of arc-deficient cells without affecting the integrity of vimentin filaments or stress fibers, demonstrating that this cytoskeletal cross-linker is required for productive interactions between vimentin and arcs. Collectively, our results reveal that plectin-mediated interplay between contractile actomyosin arcs and vimentin intermediate filaments controls the localization and dynamics of these two cytoskeletal systems and is consequently important for cell morphogenesis.

  9. An essential role of intestinal cell kinase in lung development is linked to the perinatal lethality of human ECO syndrome

    Science.gov (United States)

    Tong, Yixin; Park, So Hyun; Wu, Di; Xu, Wenhao; Guillot, Stacey J.; Jin, Li; Li, Xudong; Wang, Yalin; Lin, Chyuan-Sheng; Fu, Zheng

    2017-01-01

    Human endocrine-cerebro-osteodysplasia (ECO) syndrome, caused by the loss-of-function mutation R272Q in the ICK (intestinal cell kinase) gene, is a neonatal-lethal developmental disorder. To elucidate the molecular basis of ECO syndrome, we constructed an Ick R272Q knock-in mouse model that recapitulates ECO pathological phenotypes. Newborns bearing Ick R272Q homozygous mutations die at birth due to respiratory distress. Ick mutant lungs exhibit not only impaired branching morphogenesis associated with reduced mesenchymal proliferation, but also significant airspace deficiency in primitive alveoli concomitant with abnormal interstitial mesenchymal differentiation. ICK dysfunction induces elongated primary cilia and perturbs ciliary Hedgehog signaling and autophagy during lung sacculation. Our study identifies an essential role for ICK in lung development and advances the mechanistic understanding of ECO syndrome. PMID:28380258

  10. Linear Invariant Tensor Interpolation Applied to Cardiac Diffusion Tensor MRI

    Science.gov (United States)

    Gahm, Jin Kyu; Wisniewski, Nicholas; Kindlmann, Gordon; Kung, Geoffrey L.; Klug, William S.; Garfinkel, Alan; Ennis, Daniel B.

    2015-01-01

    Purpose Various methods exist for interpolating diffusion tensor fields, but none of them linearly interpolate tensor shape attributes. Linear interpolation is expected not to introduce spurious changes in tensor shape. Methods Herein we define a new linear invariant (LI) tensor interpolation method that linearly interpolates components of tensor shape (tensor invariants) and recapitulates the interpolated tensor from the linearly interpolated tensor invariants and the eigenvectors of a linearly interpolated tensor. The LI tensor interpolation method is compared to the Euclidean (EU), affine-invariant Riemannian (AI), log-Euclidean (LE) and geodesic-loxodrome (GL) interpolation methods using both a synthetic tensor field and three experimentally measured cardiac DT-MRI datasets. Results EU, AI, and LE introduce significant microstructural bias, which can be avoided through the use of GL or LI. Conclusion GL introduces the least microstructural bias, but LI tensor interpolation performs very similarly and at substantially reduced computational cost. PMID:23286085

  11. Malaria in pregnancy: the relevance of animal models for vaccine development.

    Science.gov (United States)

    Doritchamou, Justin; Teo, Andrew; Fried, Michal; Duffy, Patrick E

    2017-10-06

    Malaria during pregnancy due to Plasmodium falciparum or P. vivax is a major public health problem in endemic areas, with P. falciparum causing the greatest burden of disease. Increasing resistance of parasites and mosquitoes to existing tools, such as preventive antimalarial treatments and insecticide-treated bed nets respectively, is eroding the partial protection that they offer to pregnant women. Thus, development of effective vaccines against malaria during pregnancy is an urgent priority. Relevant animal models that recapitulate key features of the pathophysiology and immunology of malaria in pregnant women could be used to accelerate vaccine development. This review summarizes available rodent and nonhuman primate models of malaria in pregnancy, and discusses their suitability for studies of biologics intended to prevent or treat malaria in this vulnerable population.

  12. Disruption of the Class IIa HDAC Corepressor Complex Increases Energy Expenditure and Lipid Oxidation

    Directory of Open Access Journals (Sweden)

    Vidhi Gaur

    2016-09-01

    Full Text Available Drugs that recapitulate aspects of the exercise adaptive response have the potential to provide better treatment for diseases associated with physical inactivity. We previously observed reduced skeletal muscle class IIa HDAC (histone deacetylase transcriptional repressive activity during exercise. Here, we find that exercise-like adaptations are induced by skeletal muscle expression of class IIa HDAC mutants that cannot form a corepressor complex. Adaptations include increased metabolic gene expression, mitochondrial capacity, and lipid oxidation. An existing HDAC inhibitor, Scriptaid, had similar phenotypic effects through disruption of the class IIa HDAC corepressor complex. Acute Scriptaid administration to mice increased the expression of metabolic genes, which required an intact class IIa HDAC corepressor complex. Chronic Scriptaid administration increased exercise capacity, whole-body energy expenditure and lipid oxidation, and reduced fasting blood lipids and glucose. Therefore, compounds that disrupt class IIa HDAC function could be used to enhance metabolic health in chronic diseases driven by physical inactivity.

  13. Teaching Ethics to Engineers: A Socratic Experience.

    Science.gov (United States)

    Génova, Gonzalo; González, M Rosario

    2016-04-01

    In this paper we present the authors' experience of teaching a course in Ethics for Engineers, which has been delivered four times in three different universities in Spain and Chile. We begin by presenting the material context of the course (its place within the university program, the number of students attending, its duration, etc.), and especially the intellectual background of the participating students, in terms of their previous understanding of philosophy in general, and of ethics in particular. Next we set out the objectives of the course and the main topics addressed, as well as the methodology and teaching resources employed to have students achieve a genuine philosophical reflection on the ethical aspects of the profession, starting from their own mindset as engineers. Finally we offer some results based on opinion surveys of the students, as well as a more personal assessment by the authors, recapitulating the most significant achievements of the course and indicating its underlying Socratic structure.

  14. Are there endogenous stem cells in the spinal cord?

    Science.gov (United States)

    Ferrucci, Michela; Ryskalin, Larisa; Busceti, Carla L; Gaglione, Anderson; Biagioni, Francesca; Fornai, Francesco

    2017-12-01

    Neural progenitor cells (NPC) represent the stem-like niche of the central nervous system that maintains a regenerative potential also in the adult life. Despite NPC in the brain are well documented, the presence of NPC in the spinal cord has been controversial for a long time. This is due to a scarce activity of NPC within spinal cord, which also makes difficult their identification. The present review recapitulates the main experimental studies, which provided evidence for the occurrence of NPC within spinal cord, with a special emphasis on spinal cord injury and amyotrophic lateral sclerosis. By using experimental models, here we analyse the site-specificity, the phenotype and the main triggers of spinal cord NPC. Moreover, data are reported on the effect of specific neurogenic stimuli on these spinal cord NPC in an effort to comprehend the endogenous neurogenic potential of this stem cell niche.

  15. Targeting aerobic glycolysis: 3-bromopyruvate as a promising anticancer drug.

    Science.gov (United States)

    Cardaci, Simone; Desideri, Enrico; Ciriolo, Maria Rosa

    2012-02-01

    The Warburg effect refers to the phenomenon whereby cancer cells avidly take up glucose and produce lactic acid under aerobic conditions. Although the molecular mechanisms underlying tumor reliance on glycolysis remains not completely clear, its inhibition opens feasible therapeutic windows for cancer treatment. Indeed, several small molecules have emerged by combinatorial studies exhibiting promising anticancer activity both in vitro and in vivo, as a single agent or in combination with other therapeutic modalities. Therefore, besides reviewing the alterations of glycolysis that occur with malignant transformation, this manuscript aims at recapitulating the most effective pharmacological therapeutics of its targeting. In particular, we describe the principal mechanisms of action and the main targets of 3-bromopyruvate, an alkylating agent with impressive antitumor effects in several models of animal tumors. Moreover, we discuss the chemo-potentiating strategies that would make unparalleled the putative therapeutic efficacy of its use in clinical settings.

  16. Prolonged fasting reduces IGF-1/PKA to promote hematopoietic-stem-cell-based regeneration and reverse immunosuppression.

    Science.gov (United States)

    Cheng, Chia-Wei; Adams, Gregor B; Perin, Laura; Wei, Min; Zhou, Xiaoying; Lam, Ben S; Da Sacco, Stefano; Mirisola, Mario; Quinn, David I; Dorff, Tanya B; Kopchick, John J; Longo, Valter D

    2014-06-05

    Immune system defects are at the center of aging and a range of diseases. Here, we show that prolonged fasting reduces circulating IGF-1 levels and PKA activity in various cell populations, leading to signal transduction changes in long-term hematopoietic stem cells (LT-HSCs) and niche cells that promote stress resistance, self-renewal, and lineage-balanced regeneration. Multiple cycles of fasting abated the immunosuppression and mortality caused by chemotherapy and reversed age-dependent myeloid-bias in mice, in agreement with preliminary data on the protection of lymphocytes from chemotoxicity in fasting patients. The proregenerative effects of fasting on stem cells were recapitulated by deficiencies in either IGF-1 or PKA and blunted by exogenous IGF-1. These findings link the reduced levels of IGF-1 caused by fasting to PKA signaling and establish their crucial role in regulating hematopoietic stem cell protection, self-renewal, and regeneration. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Animal models for Gaucher disease research.

    Science.gov (United States)

    Farfel-Becker, Tamar; Vitner, Einat B; Futerman, Anthony H

    2011-11-01

    Gaucher disease (GD), the most common lysosomal storage disorder (LSD), is caused by the defective activity of the lysosomal hydrolase glucocerebrosidase, which is encoded by the GBA gene. Generation of animal models that faithfully recapitulate the three clinical subtypes of GD has proved to be more of a challenge than first anticipated. The first mouse to be produced died within hours after birth owing to skin permeability problems, and mice with point mutations in Gba did not display symptoms correlating with human disease and also died soon after birth. Recently, conditional knockout mice that mimic some features of the human disease have become available. Here, we review the contribution of all currently available animal models to examining pathological pathways underlying GD and to testing the efficacy of new treatment modalities, and propose a number of criteria for the generation of more appropriate animal models of GD.

  18. Mitochondria, Cybrids, Aging, and Alzheimer’s Disease

    Science.gov (United States)

    Swerdlow, Russell H.; Koppel, Scott; Weidling, Ian; Hayley, Clay; Ji, Yan; Wilkins, Heather M.

    2018-01-01

    Mitochondrial and bioenergetic function change with advancing age and may drive aging phenotypes. Mitochondrial and bioenergetic changes are also documented in various age-related neurodegenerative diseases, including Alzheimer’s disease (AD). In some instances AD mitochondrial and bioenergetic changes are reminiscent of those observed with advancing age, but are greater in magnitude. Mitochondrial and bioenergetic dysfunction could, therefore, link neurodegeneration to brain aging. Interestingly, mitochondrial defects in AD patients are not brain-limited, and mitochondrial function can be linked to classic AD histologic changes including amyloid precursor protein processing to beta amyloid. Also, transferring mitochondria from AD subjects to cell lines depleted of endogenous mitochondrial DNA (mtDNA) creates cytoplasmic hybrid (cybrid) cell lines that recapitulate specific biochemical, molecular, and histologic AD features. Such findings have led to the formulation of a “mitochondrial cascade hypothesis” that places mitochondrial dysfunction at the apex of the AD pathology pyramid. Data pertinent to this premise are reviewed. PMID:28253988

  19. Trehalose-6-Phosphate: connecting plant metabolism and development

    Directory of Open Access Journals (Sweden)

    Jathish ePonnu

    2011-11-01

    Full Text Available Beyond their metabolic roles, sugars can also act as messengers in signal transduction. Trehalose, a sugar found in many species of plants and animals, is a non-reducing disaccharide composed of two glucose moieties. Its synthesis in plants is a two-step process, involving the production of trehalose-6-phosphate (T6P catalyzed by TREHALOSE-6-PHOSPHATE SYNTHASE (TPS and its consecutive dephosphorylation to trehalose, catalyzed by TREHALOSE-6-PHOSPHATE PHOSPHATASE (TPP. T6P has recently emerged as an important signaling metabolite, regulating carbon assimilation and sugar status in plants. In addition, T6P has also been demonstrated to play an essential role in plant development. This review recapitulates the recent advances in our understanding the role of T6P in coordinating diverse metabolic and developmental processes.

  20. The Nuclear Factor of Activated T Cells (Nfat) Transcription Factor Nfatp (Nfatc2) Is a Repressor of Chondrogenesis

    Science.gov (United States)

    Ranger, Ann M.; Gerstenfeld, Louis C.; Wang, Jinxi; Kon, Tamiyo; Bae, Hyunsu; Gravallese, Ellen M.; Glimcher, Melvin J.; Glimcher, Laurie H.

    2000-01-01

    Nuclear factor of activated T cells (NFAT) transcription factors regulate gene expression in lymphocytes and control cardiac valve formation. Here, we report that NFATp regulates chondrogenesis in the adult animal. In mice lacking NFATp, resident cells in the extraarticular connective tissues spontaneously differentiate to cartilage. These cartilage cells progressively differentiate and the tissue undergoes endochondral ossification, recapitulating the development of endochondral bone. Proliferation of already existing articular cartilage cells also occurs in some older animals. At both sites, neoplastic changes in the cartilage cells occur. Consistent with these data, NFATp expression is regulated in mesenchymal stem cells induced to differentiate along a chondrogenic pathway. Lack of NFATp in articular cartilage cells results in increased expression of cartilage markers, whereas overexpression of NFATp in cartilage cell lines extinguishes the cartilage phenotype. Thus, NFATp is a repressor of cartilage cell growth and differentiation and also has the properties of a tumor suppressor. PMID:10620601

  1. Curing color blindness--mice and nonhuman primates.

    Science.gov (United States)

    Neitz, Maureen; Neitz, Jay

    2014-08-21

    It has been possible to use viral-mediated gene therapy to transform dichromatic (red-green color-blind) primates to trichromatic. Even though the third cone type was added after the end of developmental critical periods, treated animals acquired red-green color vision. What happened in the treated animals may represent a recapitulation of the evolution of trichromacy, which seems to have evolved with the acquisition of a third cone type without the need for subsequent modification to the circuitry. Some transgenic mice in which a third cone type was added also acquired trichromacy. However, compared with treated primates, red-green color vision in mice is poor, indicating large differences between mice and monkeys in their ability to take advantage of the new input. These results have implications for understanding the limits and opportunities for using gene therapy to treat vision disorders caused by defects in cone function. Copyright © 2014 Cold Spring Harbor Laboratory Press; all rights reserved.

  2. Curing Color Blindness—Mice and Nonhuman Primates

    Science.gov (United States)

    Neitz, Maureen; Neitz, Jay

    2014-01-01

    It has been possible to use viral-mediated gene therapy to transform dichromatic (red-green color-blind) primates to trichromatic. Even though the third cone type was added after the end of developmental critical periods, treated animals acquired red-green color vision. What happened in the treated animals may represent a recapitulation of the evolution of trichromacy, which seems to have evolved with the acquisition of a third cone type without the need for subsequent modification to the circuitry. Some transgenic mice in which a third cone type was added also acquired trichromacy. However, compared with treated primates, red-green color vision in mice is poor, indicating large differences between mice and monkeys in their ability to take advantage of the new input. These results have implications for understanding the limits and opportunities for using gene therapy to treat vision disorders caused by defects in cone function. PMID:25147187

  3. Stress Effects on Multiple Memory System Interactions

    Science.gov (United States)

    Ness, Deborah; Calabrese, Pasquale

    2016-01-01

    Extensive behavioural, pharmacological, and neurological research reports stress effects on mammalian memory processes. While stress effects on memory quantity have been known for decades, the influence of stress on multiple memory systems and their distinct contributions to the learning process have only recently been described. In this paper, after summarizing the fundamental biological aspects of stress/emotional arousal and recapitulating functionally and anatomically distinct memory systems, we review recent animal and human studies exploring the effects of stress on multiple memory systems. Apart from discussing the interaction between distinct memory systems in stressful situations, we will also outline the fundamental role of the amygdala in mediating such stress effects. Additionally, based on the methods applied in the herein discussed studies, we will discuss how memory translates into behaviour. PMID:27034845

  4. Evaluation of expansile nanoparticle tumor localization and efficacy in a cancer stem cell-derived model of pancreatic peritoneal carcinomatosis

    Science.gov (United States)

    Herrera, Victoria LM; Colby, Aaron H; Tan, Glaiza AL; Moran, Ann M; O’Brien, Michael J; Colson, Yolonda L; Ruiz-Opazo, Nelson; Grinstaff, Mark W

    2016-01-01

    Aim: To evaluate the tumor localization and efficacy pH-responsive expansile nanoparticles (eNPs) as a drug delivery system for pancreatic peritoneal carcinomatosis (PPC) modeled in nude rats. Methods & materials: A Panc-1-cancer stem cell xeno1graft model of PPC was validated in vitro and in vivo. Tumor localization was tracked via in situ imaging of fluorescent eNPs. Survival of animals treated with paclitaxel-loaded eNPs (PTX-eNPs) was evaluated in vivo. Results: The Panc-1-cancer stem cell xenograft model recapitulates significant features of PPC. Rhodamine-labeled eNPs demonstrate tumor-specific, dose- and time-dependent localization to macro- and microscopic tumors following intraperitoneal injection. PTX-eNPs are as effective as free PTX in treating established PPC; but, PTX-eNPs result in fewer side effects. Conclusion: eNPs are a promising tool for the detection and treatment of PPC. PMID:27078118

  5. BRAIN NETWORKS. Correlated gene expression supports synchronous activity in brain networks.

    Science.gov (United States)

    Richiardi, Jonas; Altmann, Andre; Milazzo, Anna-Clare; Chang, Catie; Chakravarty, M Mallar; Banaschewski, Tobias; Barker, Gareth J; Bokde, Arun L W; Bromberg, Uli; Büchel, Christian; Conrod, Patricia; Fauth-Bühler, Mira; Flor, Herta; Frouin, Vincent; Gallinat, Jürgen; Garavan, Hugh; Gowland, Penny; Heinz, Andreas; Lemaître, Hervé; Mann, Karl F; Martinot, Jean-Luc; Nees, Frauke; Paus, Tomáš; Pausova, Zdenka; Rietschel, Marcella; Robbins, Trevor W; Smolka, Michael N; Spanagel, Rainer; Ströhle, Andreas; Schumann, Gunter; Hawrylycz, Mike; Poline, Jean-Baptiste; Greicius, Michael D

    2015-06-12

    During rest, brain activity is synchronized between different regions widely distributed throughout the brain, forming functional networks. However, the molecular mechanisms supporting functional connectivity remain undefined. We show that functional brain networks defined with resting-state functional magnetic resonance imaging can be recapitulated by using measures of correlated gene expression in a post mortem brain tissue data set. The set of 136 genes we identify is significantly enriched for ion channels. Polymorphisms in this set of genes significantly affect resting-state functional connectivity in a large sample of healthy adolescents. Expression levels of these genes are also significantly associated with axonal connectivity in the mouse. The results provide convergent, multimodal evidence that resting-state functional networks correlate with the orchestrated activity of dozens of genes linked to ion channel activity and synaptic function. Copyright © 2015, American Association for the Advancement of Science.

  6. Sharing Structure and Function in Biological Design with SBOL 2.0.

    Science.gov (United States)

    Roehner, Nicholas; Beal, Jacob; Clancy, Kevin; Bartley, Bryan; Misirli, Goksel; Grünberg, Raik; Oberortner, Ernst; Pocock, Matthew; Bissell, Michael; Madsen, Curtis; Nguyen, Tramy; Zhang, Michael; Zhang, Zhen; Zundel, Zach; Densmore, Douglas; Gennari, John H; Wipat, Anil; Sauro, Herbert M; Myers, Chris J

    2016-06-17

    The Synthetic Biology Open Language (SBOL) is a standard that enables collaborative engineering of biological systems across different institutions and tools. SBOL is developed through careful consideration of recent synthetic biology trends, real use cases, and consensus among leading researchers in the field and members of commercial biotechnology enterprises. We demonstrate and discuss how a set of SBOL-enabled software tools can form an integrated, cross-organizational workflow to recapitulate the design of one of the largest published genetic circuits to date, a 4-input AND sensor. This design encompasses the structural components of the system, such as its DNA, RNA, small molecules, and proteins, as well as the interactions between these components that determine the system's behavior/function. The demonstrated workflow and resulting circuit design illustrate the utility of SBOL 2.0 in automating the exchange of structural and functional specifications for genetic parts, devices, and the biological systems in which they operate.

  7. Classical theory of algebraic numbers

    CERN Document Server

    Ribenboim, Paulo

    2001-01-01

    Gauss created the theory of binary quadratic forms in "Disquisitiones Arithmeticae" and Kummer invented ideals and the theory of cyclotomic fields in his attempt to prove Fermat's Last Theorem These were the starting points for the theory of algebraic numbers, developed in the classical papers of Dedekind, Dirichlet, Eisenstein, Hermite and many others This theory, enriched with more recent contributions, is of basic importance in the study of diophantine equations and arithmetic algebraic geometry, including methods in cryptography This book has a clear and thorough exposition of the classical theory of algebraic numbers, and contains a large number of exercises as well as worked out numerical examples The Introduction is a recapitulation of results about principal ideal domains, unique factorization domains and commutative fields Part One is devoted to residue classes and quadratic residues In Part Two one finds the study of algebraic integers, ideals, units, class numbers, the theory of decomposition, iner...

  8. An integrated miRNA functional screening and target validation method for organ morphogenesis.

    Science.gov (United States)

    Rebustini, Ivan T; Vlahos, Maryann; Packer, Trevor; Kukuruzinska, Maria A; Maas, Richard L

    2016-03-16

    The relative ease of identifying microRNAs and their increasing recognition as important regulators of organogenesis motivate the development of methods to efficiently assess microRNA function during organ morphogenesis. In this context, embryonic organ explants provide a reliable and reproducible system that recapitulates some of the important early morphogenetic processes during organ development. Here we present a method to target microRNA function in explanted mouse embryonic organs. Our method combines the use of peptide-based nanoparticles to transfect specific microRNA inhibitors or activators into embryonic organ explants, with a microRNA pulldown assay that allows direct identification of microRNA targets. This method provides effective assessment of microRNA function during organ morphogenesis, allows prioritization of multiple microRNAs in parallel for subsequent genetic approaches, and can be applied to a variety of embryonic organs.

  9. Glycogen storage disease type Ia in canines: a model for human metabolic and genetic liver disease.

    Science.gov (United States)

    Specht, Andrew; Fiske, Laurie; Erger, Kirsten; Cossette, Travis; Verstegen, John; Campbell-Thompson, Martha; Struck, Maggie B; Lee, Young Mok; Chou, Janice Y; Byrne, Barry J; Correia, Catherine E; Mah, Cathryn S; Weinstein, David A; Conlon, Thomas J

    2011-01-01

    A canine model of Glycogen storage disease type Ia (GSDIa) is described. Affected dogs are homozygous for a previously described M121I mutation resulting in a deficiency of glucose-6-phosphatase-α. Metabolic, clinicopathologic, pathologic, and clinical manifestations of GSDIa observed in this model are described and compared to those observed in humans. The canine model shows more complete recapitulation of the clinical manifestations seen in humans including "lactic acidosis", larger size, and longer lifespan compared to other animal models. Use of this model in preclinical trials of gene therapy is described and briefly compared to the murine model. Although the canine model offers a number of advantages for evaluating potential therapies for GSDIa, there are also some significant challenges involved in its use. Despite these challenges, the canine model of GSDIa should continue to provide valuable information about the potential for generating curative therapies for GSDIa as well as other genetic hepatic diseases.

  10. Glycogen Storage Disease Type Ia in Canines: A Model for Human Metabolic and Genetic Liver Disease

    Directory of Open Access Journals (Sweden)

    Andrew Specht

    2011-01-01

    Full Text Available A canine model of Glycogen storage disease type Ia (GSDIa is described. Affected dogs are homozygous for a previously described M121I mutation resulting in a deficiency of glucose-6-phosphatase-α. Metabolic, clinicopathologic, pathologic, and clinical manifestations of GSDIa observed in this model are described and compared to those observed in humans. The canine model shows more complete recapitulation of the clinical manifestations seen in humans including “lactic acidosis”, larger size, and longer lifespan compared to other animal models. Use of this model in preclinical trials of gene therapy is described and briefly compared to the murine model. Although the canine model offers a number of advantages for evaluating potential therapies for GSDIa, there are also some significant challenges involved in its use. Despite these challenges, the canine model of GSDIa should continue to provide valuable information about the potential for generating curative therapies for GSDIa as well as other genetic hepatic diseases.

  11. Psychiatry and psychotherapy: past and future.

    Science.gov (United States)

    Neill, J R; Ludwig, A M

    1980-01-01

    The place of psychotherapeutics in psychiatry is again in question. In many ways the situation recapitulates that of the late 19th century when psychotherapeutics first came upon the medical scene. The psychiatric hegemony over psychotherapeutics was the outcome of three fierce internecine "battles", (1) the "medicalization" of psychotherapeutics (1870-1910); (2) securing the psychiatric monopoly of psychotherapeutics (1890-1930); and (3) the "medicalization" of psychoanalysis (1920-1940). Three "revolutions" in psychiatry have occurred, since the stable halcyon 1950s, that have loosened the knot which binds psychotherapeutics to psychiatry. The emergence of specific psychopharmacologic therapies, the resurgence of the laboratory tradition (behaviorism) and the community-mental-health movement have diluted the importance of psychotherapeutics in treatment and widened the therapeutic franchise. In addition, there is evidence that the function of psychotherapeutics in society is itself changing. The future of psychotherapeutics in psychiatry is discussed in light of these developments.

  12. The Epstein-Barr virus BFRF1 and BFLF2 proteins interact and coexpression alters their cellular localization

    International Nuclear Information System (INIS)

    Lake, Cathleen M.; Hutt-Fletcher, Lindsey M.

    2004-01-01

    The BFRF1 protein of Epstein-Barr virus (EBV) is a recently identified membrane protein that is the homolog of the alphaherpesvirus UL34 gene product. We report here that a yeast two-hybrid screen identified the BFLF2 gene product, a homolog of alphaherpesvirus UL31, as a protein that interacts with BFRF1. Expression of BFLF2 in mammalian cells revealed a protein of approximately 28 kDa that associated with BFRF1 in a noncovalently linked complex. When expressed alone, the BFRF1 protein was found in the cytoplasm and perinuclear region. BFLF2 was found diffusely in the nucleus in the absence of BFRF1, but coexpression of BFRF1 and BFLF2 resulted in colocalization of the two proteins at the nuclear rim. These data recapitulate the behavior of the alphaherpesvirus homologs of BFRF1 and BFLF2 and suggest that functional as well as structural and positional homology may be conserved

  13. Aging of bone marrow mesenchymal stromal/stem cells: Implications on autologous regenerative medicine.

    Science.gov (United States)

    Charif, N; Li, Y Y; Targa, L; Zhang, L; Ye, J S; Li, Y P; Stoltz, J F; Han, H Z; de Isla, N

    2017-01-01

    With their proliferation, differentiation into specific cell types, and secretion properties, mesenchymal stromal/stem cells (MSC) are very interesting tools to be used in regenerative medicine. Bone marrow (BM) was the first MSC source characterized. In the frame of autologous MSC therapy, it is important to detect donor's parameters affecting MSC potency. Age of the donors appears as one parameter that could greatly affect MSC properties. Moreover, in vitro cell expansion is needed to obtain the number of cells necessary for clinical developments. It will lead to in vitro cell aging that could modify cell properties. This review recapitulates several studies evaluating the effect of in vitro and in vivo MSC aging on cell properties.

  14. The role of glioma stem cells in chemotherapy resistance and glioblastoma multiforme recurrence

    Science.gov (United States)

    Auffinger, Brenda; Spencer, Drew; Pytel, Peter; Ahmed, Atique U.; Lesniak, Maciej S.

    2016-01-01

    Glioma stem cells (GSCs) constitute a slow-dividing, small population within a heterogeneous glioblastoma. They are able to self-renew, recapitulate a whole tumor, and differentiate into other specific GBM subpopulations. Therefore, they have been held responsible for malignant relapse after primary standard therapy and the poor prognosis of recurrent GBM. The failure of current therapies to eliminate specific GSC subpopulations has been considered a major factor contributing to the inevitable recurrence in GBM patients following treatment. Here, we discuss the molecular mechanisms of chemoresistance of GSCs and the reasons why complete eradication of GSCs is so difficult to achieve. We will also describe the targeted therapies currently available towards GSCs and possible mechanisms to overcome such chemoresistance and avoid therapeutic relapse. PMID:26027432

  15. 3D Reconstruction of the Human Airway Mucosa In Vitro as an Experimental Model to Study NTHi Infections.

    Directory of Open Access Journals (Sweden)

    Pasquale Marrazzo

    Full Text Available We have established an in vitro 3D system which recapitulates the human tracheo-bronchial mucosa comprehensive of the pseudostratified epithelium and the underlying stromal tissue. In particular, we reported that the mature model, entirely constituted of primary cells of human origin, develops key markers proper of the native tissue such as the mucociliary differentiation of the epithelial sheet and the formation of the basement membrane. The infection of the pseudo-tissue with a strain of NonTypeable Haemophilus influenzae results in bacteria association and crossing of the mucus layer leading to an apparent targeting of the stromal space where they release large amounts of vesicles and form macro-structures. In summary, we propose our in vitro model as a reliable and potentially customizable system to study mid/long term host-pathogen processes.

  16. Marketing of new Technologies: The case of Renewable Energies in the UK

    DEFF Research Database (Denmark)

    Brem, Alexander; Muehlmann, F.; Sarmiento, T.

    2011-01-01

    The market in the UK for renewable energy is arguably at a very critical phase in its development. Key drivers for current policy include energy security, climate change and energy prices, added to which the UK has agreed specific targets with other EU countries to help meet these challenges....... The paper includes a general overview of worldwide energy demand and a comprehensive overview of renewable energy alternatives. Based on that, it describes the development of the UK renewables marketplace with a market overview including a summary of selected key organisations currently operating. Finally......, this paper recapitulates the key findings of our quantitative research, based on a survey of 65 organisations operating in the market, into the state of the UK market, including a view on the trends and outlook for the future. Finally, the paper offers some concluding remarks which state, among others...

  17. CAS Accelerator Physics (High-Power Hadron Machines) in Spain

    CERN Multimedia

    CAS

    2011-01-01

    The CERN Accelerator School (CAS) and ESS-Bilbao jointly organised a specialised course on High-Power Hadron Machines, held at the Hotel Barceló Nervión in Bilbao, Spain, from 24 May to 2 June, 2011.   CERN Accelerator School students. After recapitulation lectures on the essentials of accelerator physics and review lectures on the different types of accelerators, the programme focussed on the challenges of designing and operating high-power facilities. The particular problems for RF systems, beam instrumentation, vacuum, cryogenics, collimators and beam dumps were examined. Activation of equipment, radioprotection and remote handling issues were also addressed. The school was very successful, with 69 participants of 22 nationalities. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and excellent quality of their lectures. In addition to the academic programme, the participants w...

  18. Imaging the hard/soft tissue interface.

    Science.gov (United States)

    Bannerman, Alistair; Paxton, Jennifer Z; Grover, Liam M

    2014-03-01

    Interfaces between different tissues play an essential role in the biomechanics of native tissues and their recapitulation is now recognized as critical to function. As a consequence, imaging the hard/soft tissue interface has become increasingly important in the area of tissue engineering. Particularly as several biotechnology based products have made it onto the market or are close to human trials and an understanding of their function and development is essential. A range of imaging modalities have been developed that allow a wealth of information on the morphological and physical properties of samples to be obtained non-destructively in vivo or via destructive means. This review summarizes the use of a selection of imaging modalities on interfaces to date considering the strengths and weaknesses of each. We will also consider techniques which have not yet been utilized to their full potential or are likely to play a role in future work in the area.

  19. Using induced pluripotent stem cells to explore genetic and epigenetic variation associated with Alzheimer's disease.

    Science.gov (United States)

    Imm, Jennifer; Kerrigan, Talitha L; Jeffries, Aaron; Lunnon, Katie

    2017-11-01

    It is thought that both genetic and epigenetic variation play a role in Alzheimer's disease initiation and progression. With the advent of somatic cell reprogramming into induced pluripotent stem cells it is now possible to generate patient-derived cells that are able to more accurately model and recapitulate disease. Furthermore, by combining this with recent advances in (epi)genome editing technologies, it is possible to begin to examine the functional consequence of previously nominated genetic variants and infer epigenetic causality from recently identified epigenetic variants. In this review, we explore the role of genetic and epigenetic variation in Alzheimer's disease and how the functional relevance of nominated loci can be investigated using induced pluripotent stem cells and (epi)genome editing techniques.

  20. Truncating Homozygous Mutation of Carboxypeptidase E (CPE in a Morbidly Obese Female with Type 2 Diabetes Mellitus, Intellectual Disability and Hypogonadotrophic Hypogonadism.

    Directory of Open Access Journals (Sweden)

    Suzanne I M Alsters

    Full Text Available Carboxypeptidase E is a peptide processing enzyme, involved in cleaving numerous peptide precursors, including neuropeptides and hormones involved in appetite control and glucose metabolism. Exome sequencing of a morbidly obese female from a consanguineous family revealed homozygosity for a truncating mutation of the CPE gene (c.76_98del; p.E26RfsX68. Analysis detected no CPE expression in whole blood-derived RNA from the proband, consistent with nonsense-mediated decay. The morbid obesity, intellectual disability, abnormal glucose homeostasis and hypogonadotrophic hypogonadism seen in this individual recapitulates phenotypes in the previously described fat/fat and Cpe knockout mouse models, evidencing the importance of this peptide/hormone-processing enzyme in regulating body weight, metabolism, and brain and reproductive function in humans.

  1. DEPDC5 takes a second hit in familial focal epilepsy.

    Science.gov (United States)

    Anderson, Matthew P

    2018-04-30

    Loss-of-function mutations in a single allele of the gene encoding DEP domain-containing 5 protein (DEPDC5) are commonly linked to familial focal epilepsy with variable foci; however, a subset of patients presents with focal cortical dysplasia that is proposed to result from a second-hit somatic mutation. In this issue of the JCI, Ribierre and colleagues provide several lines of evidence to support second-hit DEPDC5 mutations in this disorder. Moreover, the authors use in vivo, in utero electroporation combined with CRISPR-Cas9 technology to generate a murine model of the disease that recapitulates human manifestations, including cortical dysplasia-like changes, focal seizures, and sudden unexpected death. This study provides important insights into familial focal epilepsy and provides a preclinical model for evaluating potential therapies.

  2. Tokamak research in the Soviet Union

    International Nuclear Information System (INIS)

    Strelkov, V.S.

    1981-01-01

    Important milestones on the way to the tokamak fusion reactor are recapitulated. Soviet tokamak research concentrated at the I.V. Kurchatov Institute in Moscow, the A.F. Ioffe Institute in Leningrad and the Physical-Technical Institute in Sukhumi successfully provides necessary scientific and technological data for reactor design. Achievments include, the successful operation of the first tokamak with superconducting windings (T-7) and the gyrotron set for microwave plasma heating in the T-10 tokamak. The following problems have intensively been studied: Various methods of additional plasma heating, heat and particle transport, and impurity control. The efficiency of electron-cyclotron resonance heating was demonstrated. In the Joule heating regime, both the heat conduction and diffusion rates are anomalously high, but the electron heat conduction rate decreases with increasing plasma density. Progress in impurity control makes it possible to obtain a plasma with effective charge approaching unity. (J.U.)

  3. Exploiting pluripotent stem cell technology for drug discovery, screening, safety, and toxicology assessments.

    Science.gov (United States)

    McGivern, Jered V; Ebert, Allison D

    2014-04-01

    In order for the pharmaceutical industry to maintain a constant flow of novel drugs and therapeutics into the clinic, compounds must be thoroughly validated for safety and efficacy in multiple biological and biochemical systems. Pluripotent stem cells, because of their ability to develop into any cell type in the body and recapitulate human disease, may be an important cellular system to add to the drug development repertoire. This review will discuss some of the benefits of using pluripotent stem cells for drug discovery and safety studies as well as some of the recent applications of stem cells in drug screening studies. We will also address some of the hurdles that need to be overcome in order to make stem cell-based approaches an efficient and effective tool in the quest to produce clinically successful drug compounds. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Pewarisan Karakter Fenotip Melon (Cucumis melo L. ‘Hikapel Aromatis’ Hasil Persilangan ♀ ‘Hikapel’ dengan ♂ ‘Hikadi Aromatik’

    Directory of Open Access Journals (Sweden)

    Budi Setiadi Daryono

    2018-01-01

    Full Text Available This research aims to develop cultivars with superior phenotypes of melon and high level of productivity. This research used the individual results of crossing between melon  ♀ ‘Hikapel' with ♂ 'Hikadi Aromatik'. The research included qualitative and quantitative phenotype characterization test. The research was conducted in Center of Agrotechnology Innovation University of Gadjah Mada (PIAT-UGM, Kalitirto, Berbah, Sleman, Yogyakarta and Laboratory of Genetics Faculty of Biology UGM on December 2016 until March 2017. Quantitative data analysis used ANOVA testing through PKBT-STAT 2.02 software with Random Complete Block Design (RCBD method at significance level of 1% and 5%. Melon 'Hikapel Aromatik' has several advantages including oval shape, without net, without lobes, crispy texture, skin-collored yellow RHS (6A, has a 7-14 brix, has volatile aromatic compound and transposon influenced. Based on the results of recapitulation of variance, the characters of 'Hikapel Aromatik' was not uniform.

  5. Renal-Retinal Ciliopathy Gene Sdccag8 Regulates DNA Damage Response Signaling

    DEFF Research Database (Denmark)

    Airik, Rannar; Slaats, Gisela G; Guo, Zhi

    2014-01-01

    Nephronophthisis-related ciliopathies (NPHP-RCs) are developmental and degenerative kidney diseases that are frequently associated with extrarenal pathologies such as retinal degeneration, obesity, and intellectual disability. We recently identified mutations in a gene encoding the centrosomal...... protein SDCCAG8 as causing NPHP type 10 in humans. To study the role of Sdccag8 in disease pathogenesis, we generated a Sdccag8 gene-trap mouse line. Homozygous Sdccag8(gt/gt) mice lacked the wild-type Sdccag8 transcript and protein, and recapitulated the human phenotypes of NPHP and retinal degeneration....... These mice exhibited early onset retinal degeneration that was associated with rhodopsin mislocalization in the photoreceptors and reduced cone cell numbers, and led to progressive loss of vision. By contrast, renal histologic changes occurred later, and no global ciliary defects were observed in the kidneys...

  6. SDCCAG8 Interacts with RAB Effector Proteins RABEP2 and ERC1 and Is Required for Hedgehog Signaling

    DEFF Research Database (Denmark)

    Airik, Rannar; Schueler, Markus; Airik, Merlin

    2016-01-01

    Recessive mutations in the SDCCAG8 gene cause a nephronophthisis-related ciliopathy with Bardet-Biedl syndrome-like features in humans. Our previous characterization of the orthologous Sdccag8gt/gt mouse model recapitulated the retinal-renal disease phenotypes and identified impaired DNA damage...... response signaling as an underlying disease mechanism in the kidney. However, several other phenotypic and mechanistic features of Sdccag8gt/gt mice remained unexplored. Here we show that Sdccag8gt/gt mice exhibit developmental and structural abnormalities of the skeleton and limbs, suggesting impaired...... Hedgehog (Hh) signaling. Indeed, cell culture studies demonstrate the requirement of SDCCAG8 for ciliogenesis and Hh signaling. Using an affinity proteomics approach, we demonstrate that SDCCAG8 interacts with proteins of the centriolar satellites (OFD1, AZI1), of the endosomal sorting complex (RABEP2, ERC...

  7. RSV-Induced H3K4 Demethylase KDM5B Leads to Regulation of Dendritic Cell-Derived Innate Cytokines and Exacerbates Pathogenesis In Vivo

    DEFF Research Database (Denmark)

    Ptaschinski, Catherine; Mukherjee, Sumanta; Moore, Martin L

    2015-01-01

    -transfected cells. The generation of Kdm5bfl/fl-CD11c-Cre+ mice recapitulated the latter results during in vitro DC activation showing innate cytokine modulation. In vivo, infection of Kdm5bfl/fl-CD11c-Cre+ mice with RSV resulted in higher production of IFN-γ and reduced IL-4 and IL-5 compared to littermate....../fl-CD11c-CRE mice were used, the exacerbated response was abrogated. Importantly, human monocyte-derived DCs treated with a chemical inhibitor for KDM5B resulted in increased innate cytokine levels as well as elicited decreased Th2 cytokines when co-cultured with RSV reactivated CD4+ T cells...

  8. Stingless Bee Larvae Require Fungal Steroid to Pupate.

    Science.gov (United States)

    Paludo, Camila R; Menezes, Cristiano; Silva-Junior, Eduardo A; Vollet-Neto, Ayrton; Andrade-Dominguez, Andres; Pishchany, Gleb; Khadempour, Lily; do Nascimento, Fabio S; Currie, Cameron R; Kolter, Roberto; Clardy, Jon; Pupo, Mônica T

    2018-01-18

    The larval stage of the stingless bee Scaptotrigona depilis must consume a specific brood cell fungus in order to continue development. Here we show that this fungus is a member of the genus Zygosaccharomyces and provides essential steroid precursors to the developing bee. Insect pupation requires ecdysteroid hormones, and as insects cannot synthesize sterols de novo, they must obtain steroids in their diet. Larval in vitro culturing assays demonstrated that consuming ergosterol recapitulates the developmental effects on S. depilis as ingestion of Zygosaccharomyces sp. cells. Thus, we determined the molecular underpinning of this intimate mutualistic symbiosis. Phylogenetic analyses showed that similar cases of bee-Zygosaccharomyces symbiosis may exist. This unprecedented case of bee-fungus symbiosis driven by steroid requirement brings new perspectives regarding pollinator-microbiota interaction and preservation.

  9. The diaphragms of fenestrated endothelia: gatekeepers of vascular permeability and blood composition.

    Science.gov (United States)

    Stan, Radu V; Tse, Dan; Deharvengt, Sophie J; Smits, Nicole C; Xu, Yan; Luciano, Marcus R; McGarry, Caitlin L; Buitendijk, Maarten; Nemani, Krishnamurthy V; Elgueta, Raul; Kobayashi, Takashi; Shipman, Samantha L; Moodie, Karen L; Daghlian, Charles P; Ernst, Patricia A; Lee, Hong-Kee; Suriawinata, Arief A; Schned, Alan R; Longnecker, Daniel S; Fiering, Steven N; Noelle, Randolph J; Gimi, Barjor; Shworak, Nicholas W; Carrière, Catherine

    2012-12-11

    Fenestral and stomatal diaphragms are endothelial subcellular structures of unknown function that form on organelles implicated in vascular permeability: fenestrae, transendothelial channels, and caveolae. PV1 protein is required for diaphragm formation in vitro. Here, we report that deletion of the PV1-encoding Plvap gene in mice results in the absence of diaphragms and decreased survival. Loss of diaphragms did not affect the fenestrae and transendothelial channels formation but disrupted the barrier function of fenestrated capillaries, causing a major leak of plasma proteins. This disruption results in early death of animals due to severe noninflammatory protein-losing enteropathy. Deletion of PV1 in endothelium, but not in the hematopoietic compartment, recapitulates the phenotype of global PV1 deletion, whereas endothelial reconstitution of PV1 rescues the phenotype. Taken together, these data provide genetic evidence for the critical role of the diaphragms in fenestrated capillaries in the maintenance of blood composition. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Loss of Akt1 in mice increases energy expenditure and protects against diet-induced obesity.

    Science.gov (United States)

    Wan, Min; Easton, Rachael M; Gleason, Catherine E; Monks, Bobby R; Ueki, Kohjiro; Kahn, C Ronald; Birnbaum, Morris J

    2012-01-01

    Akt is encoded by a gene family for which each isoform serves distinct but overlapping functions. Based on the phenotypes of the germ line gene disruptions, Akt1 has been associated with control of growth, whereas Akt2 has been linked to metabolic regulation. Here we show that Akt1 serves an unexpected role in the regulation of energy metabolism, as mice deficient for Akt1 exhibit protection from diet-induced obesity and its associated insulin resistance. Although skeletal muscle contributes most of the resting and exercising energy expenditure, muscle-specific deletion of Akt1 does not recapitulate the phenotype, indicating that the role of Akt1 in skeletal muscle is cell nonautonomous. These data indicate a previously unknown function of Akt1 in energy metabolism and provide a novel target for treatment of obesity.

  11. Mouse Models for Studying Oral Cancer: Impact in the Era of Cancer Immunotherapy.

    Science.gov (United States)

    Luo, J J; Young, C D; Zhou, H M; Wang, X J

    2018-04-01

    Model systems for oral cancer research have progressed from tumor epithelial cell cultures to in vivo systems that mimic oral cancer genetics, pathological characteristics, and tumor-stroma interactions of oral cancer patients. In the era of cancer immunotherapy, it is imperative to use model systems to test oral cancer prevention and therapeutic interventions in the presence of an immune system and to discover mechanisms of stromal contributions to oral cancer carcinogenesis. Here, we review in vivo mouse model systems commonly used for studying oral cancer and discuss the impact these models are having in advancing basic mechanisms, chemoprevention, and therapeutic intervention of oral cancer while highlighting recent discoveries concerning the role of immune cells in oral cancer. Improvements to in vivo model systems that highly recapitulate human oral cancer hold the key to identifying features of oral cancer initiation, progression, and invasion as well as molecular and cellular targets for prevention, therapeutic response, and immunotherapy development.

  12. Combined Gluteus and Pudendal Thigh Flap Reconstruction of Vaginal Defects following Robotic Abdominoperineal Resection

    Directory of Open Access Journals (Sweden)

    Kasandra R. Dassoulas, MD

    2017-09-01

    Full Text Available Summary:. Low-lying rectal cancers are being treated more frequently with robotic-assisted abdominoperineal resection, obviating the need for laparotomy and the ability to raise vertical rectus abdominis musculocutaneous flaps. For female patients, posterior vaginectomy often accompanies the resection. Combined pudendal thigh flaps as an extension of bilateral gluteus advancement flaps allow for posterior vaginal resurfacing with thin pliable fasciocutaneous flaps, which rest on the gluteal flap soft-tissue bulk that obliterates the pelvic dead space. For patients with advanced cancers who have had neoadjuvant chemoradiation, the pudendal skin paddle can be planned more laterally to bring in healthier medial thigh skin. The donor incisions lie within the gluteal cleft and crease and groin creases recapitulating normal perineal anatomy and aesthetics.

  13. The role of glucocorticoid, interleukin-1β, and antioxidants in prenatal stress effects on embryonic microglia.

    Science.gov (United States)

    Bittle, Jada; Stevens, Hanna E

    2018-02-16

    Maternal stress during pregnancy is associated with an increased risk of psychopathology in offspring. Resident immune cells of the brain, microglia, may be mediators of prenatal stress and altered neurodevelopment. Here, we demonstrate that neither the exogenous pro-inflammatory cytokine, interleukin-1β (IL-1β), nor the glucocorticoid hormone, corticosterone, recapitulated the full effects of prenatal stress on the morphology of microglial cells in the cortical plate of embryonic mice; IL-1β effects showed greater similarity to prenatal stress effects on microglia. Unexpectedly, oil vehicle alone, which has antioxidant properties, moderated the effects of prenatal stress on microglia. Microglia changes with prenatal stress were also sensitive to the antioxidant, N-acetylcysteine, suggesting redox dysregulation as a mechanism of prenatal stress.

  14. Radioactivity and food choice: risk factors and perception

    International Nuclear Information System (INIS)

    Binnerts, W.T.; Hermsen, S.; Kamp, M. van der; Loyens, L.; Ruven, H.J.T.

    1986-01-01

    A preceding study revealed much difference among a selected number of radioisotopes in the passing of the food chains. The present study confirms the possibility to reduce radioactivity intake by a careful food choice. The physiology of metabolism of 131 I, 90 Sr and 137 Cs, and other radionuclides is shortly recapitulated. Discrimination and speciation are seen to be main factors in reduction or enrichment in animal food products. Several calculations are given relating intake of radioactivity and food sources. Risk factors are mentioned, as well as the psychology around them. Although it is not urgent, it seems possible to reduce the intake of radioactivity by individuals, mainly by preference for animal products (except milk during the first weeks of a nuclear incident), and by consumption of refined food instead of 'health products'. For mankind as a whole, the popular conceptions about risk and health food need to be studied first and to be redressed, eventually. 13 refs.; 1 figure; 3 tabs

  15. First decade: TVA's first ten years of nuclear power plant design and construction experience

    International Nuclear Information System (INIS)

    Willis, W.F.

    1978-01-01

    This paper reviews the experience of the Tennessee Valley Authority's design and construction program for nuclear power plants in terms of schedule and capital costs in three separate phases. Phase one recapitulates the status of the nuclear power industry in 1966 and sets forth the assumptions used for estimating capital costs and projecting schedules for the first Tennessee Valley Authority units. Phase two describes what happened to the program in the hectic early 1970s in terms of expansion of scope (particularly for safety features), the dramatic increase in regulatory requirements, vendor problems, stretchout of project schedules, and unprecented inflation. Phase three addresses the assumptions used today in estimating schedules and plant costs for the next 10-year period. 7 figures, 7 tables

  16. Concepts in particle physics a concise introduction to the standard model

    CERN Document Server

    Nair, V Parameswaran

    2018-01-01

    The 2013 discovery of the Higgs boson posed a challenge to both physics undergraduates and their instructors. Since particle physics is seldom taught at the undergraduate level, the question "what is the Higgs and why does its discovery matter?" is a common question among undergraduates. Equally, answering this question is a problem for physics instructors. This book is an attempt to put the key concepts of particle physics together in an appealing way, and yet give enough extra tidbits for students seriously considering graduate studies in particle physics. It starts with some recapitulation of relativity and quantum mechanics, and then builds on it to give both conceptual ideas regarding the Standard Model of particle physics as well as technical details. It is presented in an informal lecture style, and includes "remarks" sections where extra material, history, or technical details are presented for the interested student. The last lecture presents an assessment of the open questions, and where the future...

  17. Quantum physics meets biology.

    Science.gov (United States)

    Arndt, Markus; Juffmann, Thomas; Vedral, Vlatko

    2009-12-01

    Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the past decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world-view of quantum coherences, entanglement, and other nonclassical effects, has been heading toward systems of increasing complexity. The present perspective article shall serve as a "pedestrian guide" to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future "quantum biology," its current status, recent experimental progress, and also the restrictions that nature imposes on bold extrapolations of quantum theory to macroscopic phenomena.

  18. Toward the Validation of Maternal Embryonic Leucine Zipper Kinase: Discovery, Optimization of Highly Potent and Selective Inhibitors, and Preliminary Biology Insight

    Energy Technology Data Exchange (ETDEWEB)

    Touré, B. Barry; Giraldes, John; Smith, Troy; Sprague, Elizabeth R.; Wang, Yaping; Mathieu, Simon; Chen, Zhuoliang; Mishina, Yuji; Feng, Yun; Yan-Neale, Yan; Shakya, Subarna; Chen, Dongshu; Meyer, Matthew; Puleo, David; Brazell, J. Tres; Straub, Christopher; Sage, David; Wright, Kirk; Yuan, Yanqiu; Chen, Xin; Duca, Jose; Kim, Sean; Tian, Li; Martin, Eric; Hurov, Kristen; Shao, Wenlin (Novartis)

    2016-05-26

    MELK kinase has been implicated in playing an important role in tumorigenesis. Our previous studies suggested that MELK is involved in the regulation of cell cycle and its genetic depletion leads to growth inhibition in a subset of high MELK-expressing basal-like breast cancer cell lines. Herein we describe the discovery and optimization of novel MELK inhibitors 8a and 8b that recapitulate the cellular effects observed by short hairpin ribonucleic acid (shRNA)-mediated MELK knockdown in cellular models. We also discovered a novel fluorine-induced hydrophobic collapse that locked the ligand in its bioactive conformation and led to a 20-fold gain in potency. These novel pharmacological inhibitors achieved high exposure in vivo and were well tolerated, which may allow further in vivo evaluation.

  19. Rapid Cellular Phenotyping of Human Pluripotent Stem Cell-Derived Cardiomyocytes using a Genetically Encoded Fluorescent Voltage Sensor

    Directory of Open Access Journals (Sweden)

    Jordan S. Leyton-Mange

    2014-02-01

    Full Text Available In addition to their promise in regenerative medicine, pluripotent stem cells have proved to be faithful models of many human diseases. In particular, patient-specific stem cell-derived cardiomyocytes recapitulate key features of several life-threatening cardiac arrhythmia syndromes. For both modeling and regenerative approaches, phenotyping of stem cell-derived tissues is critical. Cellular phenotyping has largely relied upon expression of lineage markers rather than physiologic attributes. This is especially true for cardiomyocytes, in part because electrophysiological recordings are labor intensive. Likewise, most optical voltage indicators suffer from phototoxicity, which damages cells and degrades signal quality. Here we present the use of a genetically encoded fluorescent voltage indicator, ArcLight, which we demonstrate can faithfully report transmembrane potentials in human stem cell-derived cardiomyocytes. We demonstrate the application of this fluorescent sensor in high-throughput, serial phenotyping of differentiating cardiomyocyte populations and in screening for drug-induced cardiotoxicity.

  20. Induction of pluripotency by defined factors

    Energy Technology Data Exchange (ETDEWEB)

    Okita, Keisuke, E-mail: okita@cira.kyoto-u.ac.jp [Center for iPS Cell Research and Application (CiRA), Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto 606-8507 (Japan); Yamanaka, Shinya [Center for iPS Cell Research and Application (CiRA), Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto 606-8507 (Japan); Department of Stem Cell Biology, Institute for Frontier Medical Sciences, Kyoto University, Kyoto 606-8507 (Japan); Yamanaka iPS Cell Special Project, Japan Science and Technology Agency, Kawaguchi 332-0012 (Japan); Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158 (United States)

    2010-10-01

    Somatic cells can be reprogrammed into pluripotent stem cells by introducing a combination of several transcription factors. The induced pluripotent stem (iPS) cells from a patient's somatic cells could be useful source of cells for drug discovery and cell transplantation therapies. However, most human iPS cells are made by viral vectors, such as retrovirus and lentivirus, which integrate the reprogramming factors into host genomes and may increase the risk of tumor formation. Studies of the mechanisms underlying the reprogramming and establishment of non-integration methods contribute evidence to resolve the safety concerns associated with iPS cells. On the other hand, patient-specific iPS cells have already been established and used for recapitulating disease pathology.

  1. Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes Afford New Opportunities in Inherited Cardiovascular Disease Modeling

    Directory of Open Access Journals (Sweden)

    Daniel R. Bayzigitov

    2016-01-01

    Full Text Available Fundamental studies of molecular and cellular mechanisms of cardiovascular disease pathogenesis are required to create more effective and safer methods of their therapy. The studies can be carried out only when model systems that fully recapitulate pathological phenotype seen in patients are used. Application of laboratory animals for cardiovascular disease modeling is limited because of physiological differences with humans. Since discovery of induced pluripotency generating induced pluripotent stem cells has become a breakthrough technology in human disease modeling. In this review, we discuss a progress that has been made in modeling inherited arrhythmias and cardiomyopathies, studying molecular mechanisms of the diseases, and searching for and testing drug compounds using patient-specific induced pluripotent stem cell-derived cardiomyocytes.

  2. Induction of pluripotency by defined factors

    International Nuclear Information System (INIS)

    Okita, Keisuke; Yamanaka, Shinya

    2010-01-01

    Somatic cells can be reprogrammed into pluripotent stem cells by introducing a combination of several transcription factors. The induced pluripotent stem (iPS) cells from a patient's somatic cells could be useful source of cells for drug discovery and cell transplantation therapies. However, most human iPS cells are made by viral vectors, such as retrovirus and lentivirus, which integrate the reprogramming factors into host genomes and may increase the risk of tumor formation. Studies of the mechanisms underlying the reprogramming and establishment of non-integration methods contribute evidence to resolve the safety concerns associated with iPS cells. On the other hand, patient-specific iPS cells have already been established and used for recapitulating disease pathology.

  3. Cardiotoxicity evaluation using human embryonic stem cells and induced pluripotent stem cell-derived cardiomyocytes.

    Science.gov (United States)

    Zhao, Qi; Wang, Xijie; Wang, Shuyan; Song, Zheng; Wang, Jiaxian; Ma, Jing

    2017-03-09

    Cardiotoxicity remains an important concern in drug discovery. Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have become an attractive platform to evaluate cardiotoxicity. However, the consistency between human embryonic stem cell-derived cardiomyocytes (hESC-CMs) and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in prediction of cardiotoxicity has yet to be elucidated. Here we screened the toxicities of four representative drugs (E-4031, isoprenaline, quinidine, and haloperidol) using both hESC-CMs and hiPSC-CMs, combined with an impedance-based bioanalytical method. It showed that both hESC-CMs and hiPSC-CMs can recapitulate cardiotoxicity and identify the effects of well-characterized compounds. The combined platform of hPSC-CMs and an impedance-based bioanalytical method could improve preclinical cardiotoxicity screening, holding great potential for increasing drug development accuracy.

  4. Zebrafish as a Model for the Study of Human Myeloid Malignancies

    Directory of Open Access Journals (Sweden)

    Jeng-Wei Lu

    2015-01-01

    Full Text Available Myeloid malignancies are heterogeneous disorders characterized by uncontrolled proliferation or/and blockage of differentiation of myeloid progenitor cells. Although a substantial number of gene alterations have been identified, the mechanism by which these abnormalities interact has yet to be elucidated. Over the past decades, zebrafish have become an important model organism, especially in biomedical research. Several zebrafish models have been developed to recapitulate the characteristics of specific myeloid malignancies that provide novel insight into the pathogenesis of these diseases and allow the evaluation of novel small molecule drugs. This report will focus on illustrative examples of applications of zebrafish models, including transgenesis, zebrafish xenograft models, and cell transplantation approaches, to the study of human myeloid malignancies.

  5. Transcriptomic profiling of primary alveolar epithelial cell differentiation in human and rat

    Directory of Open Access Journals (Sweden)

    Crystal N. Marconett

    2014-12-01

    Full Text Available Cell-type specific gene regulation is a key to gaining a full understanding of how the distinct phenotypes of differentiated cells are achieved and maintained. Here we examined how changes in transcriptional activation during alveolar epithelial cell (AEC differentiation determine phenotype. We performed transcriptomic profiling using in vitro differentiation of human and rat primary AEC. This model recapitulates in vitro an in vivo process in which AEC transition from alveolar type 2 (AT2 cells to alveolar type 1 (AT1 cells during normal maintenance and regeneration following lung injury. Here we describe in detail the quality control, preprocessing, and normalization of microarray data presented within the associated study (Marconett et al., 2013. We also include R code for reproducibility of the referenced data and easily accessible processed data tables.

  6. Human pluripotent stem cells: an emerging model in developmental biology.

    Science.gov (United States)

    Zhu, Zengrong; Huangfu, Danwei

    2013-02-01

    Developmental biology has long benefited from studies of classic model organisms. Recently, human pluripotent stem cells (hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, have emerged as a new model system that offers unique advantages for developmental studies. Here, we discuss how studies of hPSCs can complement classic approaches using model organisms, and how hPSCs can be used to recapitulate aspects of human embryonic development 'in a dish'. We also summarize some of the recently developed genetic tools that greatly facilitate the interrogation of gene function during hPSC differentiation. With the development of high-throughput screening technologies, hPSCs have the potential to revolutionize gene discovery in mammalian development.

  7. Dogs as a Model for Cancer.

    Science.gov (United States)

    Gardner, Heather L; Fenger, Joelle M; London, Cheryl A

    2016-01-01

    Spontaneous cancers in client-owned dogs closely recapitulate their human counterparts with respect to clinical presentation, histological features, molecular profiles, and response and resistance to therapy, as well as the evolution of drug-resistant metastases. In several instances the incorporation of dogs with cancer into the preclinical development path of cancer therapeutics has influenced outcome by helping to establish pharmacokinetic/pharmacodynamics relationships, dose/regimen, expected clinical toxicities, and ultimately the potential for biologic activity. As our understanding regarding the molecular drivers of canine cancers has improved, unique opportunities have emerged to leverage this spontaneous model to better guide cancer drug development so that therapies likely to fail are eliminated earlier and therapies with true potential are optimized prior to human studies. Both pets and people benefit from this approach, as it provides dogs with access to cutting-edge cancer treatments and helps to insure that people are given treatments more likely to succeed.

  8. Knockout of the PKN Family of Rho Effector Kinases Reveals a Non-redundant Role for PKN2 in Developmental Mesoderm Expansion

    Directory of Open Access Journals (Sweden)

    Ivan Quétier

    2016-01-01

    Full Text Available In animals, the protein kinase C (PKC family has expanded into diversely regulated subgroups, including the Rho family-responsive PKN kinases. Here, we describe knockouts of all three mouse PKN isoforms and reveal that PKN2 loss results in lethality at embryonic day 10 (E10, with associated cardiovascular and morphogenetic defects. The cardiovascular phenotype was not recapitulated by conditional deletion of PKN2 in endothelial cells or the developing heart. In contrast, inducible systemic deletion of PKN2 after E7 provoked collapse of the embryonic mesoderm. Furthermore, mouse embryonic fibroblasts, which arise from the embryonic mesoderm, depend on PKN2 for proliferation and motility. These cellular defects are reflected in vivo as dependence on PKN2 for mesoderm proliferation and neural crest migration. We conclude that failure of the mesoderm to expand in the absence of PKN2 compromises cardiovascular integrity and development, resulting in lethality.

  9. Tracking gauge symmetry factorizability on intervals

    International Nuclear Information System (INIS)

    Ngoc-Khanh Tran

    2006-01-01

    We track the gauge symmetry breaking pattern by boundary conditions on fifth and higher-dimensional intervals. It is found that, with Dirichlet-Neumann boundary conditions, the Kaluza-Klein decomposition in five-dimension for arbitrary gauge group can always be factorized into that for separate subsets of at most two gauge symmetries, and so is completely solvable. Accordingly, we present a simple and systematic geometric method to unambiguously identify the gauge breaking/mixing content by general set of Dirichlet-Neumann boundary conditions. We then formulate a limit theorem on gauge symmetry factorizability to recapitulate this interesting feature. Albeit the breaking/mixing, a particularly simple check of orthogonality and normalization of fields' modes in effective 4-dim picture is explicitly obtained. An interesting chained-mixing of gauge symmetries in higher dimensions by Dirichlet-Neumann boundary conditions is also explicitly constructed. This study has direct applications to higgsless/GUT model building

  10. Complexity-aware simple modeling.

    Science.gov (United States)

    Gómez-Schiavon, Mariana; El-Samad, Hana

    2018-02-26

    Mathematical models continue to be essential for deepening our understanding of biology. On one extreme, simple or small-scale models help delineate general biological principles. However, the parsimony of detail in these models as well as their assumption of modularity and insulation make them inaccurate for describing quantitative features. On the other extreme, large-scale and detailed models can quantitatively recapitulate a phenotype of interest, but have to rely on many unknown parameters, making them often difficult to parse mechanistically and to use for extracting general principles. We discuss some examples of a new approach-complexity-aware simple modeling-that can bridge the gap between the small-scale and large-scale approaches. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Comparative expression analysis reveals lineage relationships between human and murine gliomas and a dominance of glial signatures during tumor propagation in vitro.

    Science.gov (United States)

    Henriquez, Nico V; Forshew, Tim; Tatevossian, Ruth; Ellis, Matthew; Richard-Loendt, Angela; Rogers, Hazel; Jacques, Thomas S; Reitboeck, Pablo Garcia; Pearce, Kerra; Sheer, Denise; Grundy, Richard G; Brandner, Sebastian

    2013-09-15

    Brain tumors are thought to originate from stem/progenitor cell populations that acquire specific genetic mutations. Although current preclinical models have relevance to human pathogenesis, most do not recapitulate the histogenesis of the human disease. Recently, a large series of human gliomas and medulloblastomas were analyzed for genetic signatures of prognosis and therapeutic response. Using a mouse model system that generates three distinct types of intrinsic brain tumors, we correlated RNA and protein expression levels with human brain tumors. A combination of genetic mutations and cellular environment during tumor propagation defined the incidence and phenotype of intrinsic murine tumors. Importantly, in vitro passage of cancer stem cells uniformly promoted a glial expression profile in culture and in brain tumors. Gene expression profiling revealed that experimental gliomas corresponded to distinct subclasses of human glioblastoma, whereas experimental supratentorial primitive neuroectodermal tumors (sPNET) correspond to atypical teratoid/rhabdoid tumor (AT/RT), a rare childhood tumor. ©2013 AACR.

  12. BAD knockout provides metabolic seizure resistance in a genetic model of epilepsy with sudden unexplained death in epilepsy.

    Science.gov (United States)

    Foley, Jeannine; Burnham, Veronica; Tedoldi, Meghan; Danial, Nika N; Yellen, Gary

    2018-01-01

    Metabolic alteration, either through the ketogenic diet (KD) or by genetic alteration of the BAD protein, can produce seizure protection in acute chemoconvulsant models of epilepsy. To assess the seizure-protective role of knocking out (KO) the Bad gene in a chronic epilepsy model, we used the Kcna1 -/- model of epilepsy, which displays progressively increased seizure severity and recapitulates the early death seen in sudden unexplained death in epilepsy (SUDEP). Beginning on postnatal day 24 (P24), we continuously video monitored Kcna1 -/- and Kcna1 -/- Bad -/- double knockout mice to assess survival and seizure severity. We found that Kcna1 -/- Bad -/- mice outlived Kcna1 -/- mice by approximately 2 weeks. Kcna1 -/- Bad -/- mice also spent significantly less time in seizure than Kcna1 -/- mice on P24 and the day of death, showing that BadKO provides seizure resistance in a genetic model of chronic epilepsy. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

  13. The compulsion to repeat relationships with abusive partners and how group therapy can help.

    Science.gov (United States)

    Nicholas, Mary W

    2013-07-01

    The mystery of why some people are compelled to repeatedly engage in relationships with people who are cruel to them is frequently pondered in literature and psychology. The present paper posits that the etiology of this pathological relationship pattern derives from a parental relationship that was both highly exciting and highly frustrating. Spontaneous recapitulations of the passionate masochistic relationship in the therapy group allow the patient, the therapist and the group to appreciate the exact nature of the "bad" partner's appeal for the patient and its link to parental antecedents. In addition, the author suggests, group therapy can provide attachment experiences that are stimulating and rewarding enough to override the patient's attraction to the toxic partner(s) and build an enhanced capacity for intimacy. The cases of two patients are presented who spent three and a half years in the same long term psychodynamic group, and who, through the processes described above, successfully resolved their masochistic relationship patterns.

  14. Tumor evolutionary directed graphs and the history of chronic lymphocytic leukemia.

    Science.gov (United States)

    Wang, Jiguang; Khiabanian, Hossein; Rossi, Davide; Fabbri, Giulia; Gattei, Valter; Forconi, Francesco; Laurenti, Luca; Marasca, Roberto; Del Poeta, Giovanni; Foà, Robin; Pasqualucci, Laura; Gaidano, Gianluca; Rabadan, Raul

    2014-12-11

    Cancer is a clonal evolutionary process, caused by successive accumulation of genetic alterations providing milestones of tumor initiation, progression, dissemination, and/or resistance to certain therapeutic regimes. To unravel these milestones we propose a framework, tumor evolutionary directed graphs (TEDG), which is able to characterize the history of genetic alterations by integrating longitudinal and cross-sectional genomic data. We applied TEDG to a chronic lymphocytic leukemia (CLL) cohort of 70 patients spanning 12 years and show that: (a) the evolution of CLL follows a time-ordered process represented as a global flow in TEDG that proceeds from initiating events to late events; (b) there are two distinct and mutually exclusive evolutionary paths of CLL evolution; (c) higher fitness clones are present in later stages of the disease, indicating a progressive clonal replacement with more aggressive clones. Our results suggest that TEDG may constitute an effective framework to recapitulate the evolutionary history of tumors.

  15. Grappling with the HOX network in hematopoiesis and leukemia.

    Science.gov (United States)

    McGonigle, Glenda J; Lappin, Terence R J; Thompson, Alexander

    2008-05-01

    The mammalian HOX gene network encodes a family of proteins which act as master regulators of developmental processes such as embryogenesis and hematopoiesis. The complex arrangement, regulation and co-factor association of HOX has been an area of intense research, particularly in cancer biology, for over a decade. The concept of redeployment of embryonic regulators in the neoplastic arena has received support from many quarters. Observations of altered HOX gene expression in various solid tumours and leukemia appear to support the thesis that 'oncology recapitulates ontogeny' but the identification of critical HOX subsets and their functional role in cancer onset and maintenance requires further investigation. The application of novel techniques and model systems will continue to enhance our understanding of the HOX network in the years to come. Better understanding of the intricacy of the complex as well as identification of functional pathways and direct targets of the encoded proteins will permit harnessing of this family of genes for clinical application.

  16. The Secret Life of Exosomes: What Bees Can Teach Us About Next-Generation Therapeutics.

    Science.gov (United States)

    Marbán, Eduardo

    2018-01-16

    Mechanistic exploration has pinpointed nanosized extracellular vesicles, known as exosomes, as key mediators of the benefits of cell therapy. Exosomes appear to recapitulate the benefits of cells and more. As durable azoic entities, exosomes have numerous practical and conceptual advantages over cells. Will cells end up just being used to manufacture exosomes, or will they find lasting value as primary therapeutic agents? Here, a venerable natural process-the generation of honey-serves as an instructive parable. Flowers make nectar, which bees collect and process into honey. Cells make conditioned medium, which laboratory workers collect and process into exosomes. Unlike flowers, honey is durable, compact, and nutritious, but these facts do not negate the value of flowers themselves. The parallels suggest new ways of thinking about next-generation therapeutics. Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  17. Online luminosity measurement at BES III

    International Nuclear Information System (INIS)

    Song Wenbo; Fu Chengdong; Mo Xiaohu; He Kanglin; Zhu Kejun; Li Fei; Zhao Shujun

    2010-01-01

    As a crucial parameter of both accelerator and detector, the realization of online luminosity measurement is of great importance. Several methods of luminosity measurement are recapitulated and the emphasis is laid on the algorithm of using e + e - and γγ final states. Taking into account the status at the beginning of the joint commissioning of detector and accelerator, the information from end cap electromagnetic calorimeter is used to select the good event. With the help of online Event filter, the luminosity is calculated and the monitoring of online cross section of hadron is realized. The preliminary results indicate that the online luminosity measurement is stable and its role for machine tuning and monitoring of the overall running status is indispensable. (authors)

  18. Microfluidic Organ/Body-on-a-Chip Devices at the Convergence of Biology and Microengineering

    Directory of Open Access Journals (Sweden)

    Ana Rubina Perestrelo

    2015-12-01

    Full Text Available Recent advances in biomedical technologies are mostly related to the convergence of biology with microengineering. For instance, microfluidic devices are now commonly found in most research centers, clinics and hospitals, contributing to more accurate studies and therapies as powerful tools for drug delivery, monitoring of specific analytes, and medical diagnostics. Most remarkably, integration of cellularized constructs within microengineered platforms has enabled the recapitulation of the physiological and pathological conditions of complex tissues and organs. The so-called “organ-on-a-chip” technology, which represents a new avenue in the field of advanced in vitro models, with the potential to revolutionize current approaches to drug screening and toxicology studies. This review aims to highlight recent advances of microfluidic-based devices towards a body-on-a-chip concept, exploring their technology and broad applications in the biomedical field.

  19. Bent bone dysplasia (BBD)-FGFR2 type: the radiologic manifestations in early gestation

    Energy Technology Data Exchange (ETDEWEB)

    Handa, Atsuhiko; Okajima, Yuka; Kurihara, Yasuyuki [St. Luke' s International Hospital, Department of Radiology, Tokyo (Japan); Izumi, Noriko; Yamanaka, Michiko [St. Luke' s International Hospital, Department of Integrated Women' s Health, Tokyo (Japan)

    2016-02-15

    Bent bone dysplasia-fibroblast growth factor receptor 2 type (BBD-FGFR2) is a recently identified skeletal dysplasia caused by specific FGFR2 mutations, characterized by craniosynostosis and prenatal bowing of the long bones. Only a few cases have been published. We report an affected fetus terminated at 21 weeks of gestation. The clinical and radiologic manifestations mostly recapitulate previous descriptions; however we suggest additional hallmarks of this disorder in early gestation. These hallmarks include distinctive short, thick clavicles and wavy ribs, as well as vertebral bodies that showed striking anteroposterior shortening. Femoral fractures were also present in our case. Although craniosynostosis is a hallmark of the disease, clinicians should be aware that craniosynostosis might not be readily apparent on plain films early in gestation. (orig.)

  20. Tributyltin and Zebrafish: Swimming in Dangerous Water

    Directory of Open Access Journals (Sweden)

    Clemilson Berto-Júnior

    2018-04-01

    Full Text Available Zebrafish has been established as a reliable biological model with important insertion in academy (morphologic, biochemical, and pathophysiological studies and pharmaceutical industry (toxicology and drug development due to its molecular complexity and similar systems biology that recapitulate those from other organisms. Considering the toxicological aspects, many efforts using zebrafish models are being done in order to elucidate the effects of endocrine disruptors, and some of them are focused on tributyltin (TBT and its mechanism of action. TBT is an antifouling agent applied in ship’s hull that is constantly released into the water and absorbed by marine organisms, leading to bioaccumulation and biomagnification effects. Thus, several findings of malformations and changes in the normal biochemical and physiologic aspects of these marine animals have been related to TBT contamination. In the present review, we have compiled the most significant studies related to TBT effects in zebrafish, also taking into consideration the effects found in other study models.

  1. Tributyltin and Zebrafish: Swimming in Dangerous Water

    Science.gov (United States)

    Berto-Júnior, Clemilson; de Carvalho, Denise Pires; Soares, Paula; Miranda-Alves, Leandro

    2018-01-01

    Zebrafish has been established as a reliable biological model with important insertion in academy (morphologic, biochemical, and pathophysiological studies) and pharmaceutical industry (toxicology and drug development) due to its molecular complexity and similar systems biology that recapitulate those from other organisms. Considering the toxicological aspects, many efforts using zebrafish models are being done in order to elucidate the effects of endocrine disruptors, and some of them are focused on tributyltin (TBT) and its mechanism of action. TBT is an antifouling agent applied in ship’s hull that is constantly released into the water and absorbed by marine organisms, leading to bioaccumulation and biomagnification effects. Thus, several findings of malformations and changes in the normal biochemical and physiologic aspects of these marine animals have been related to TBT contamination. In the present review, we have compiled the most significant studies related to TBT effects in zebrafish, also taking into consideration the effects found in other study models. PMID:29692757

  2. Self-organization of spatial patterning in human embryonic stem cells

    Science.gov (United States)

    Deglincerti, Alessia; Etoc, Fred; Ozair, M. Zeeshan; Brivanlou, Ali H.

    2017-01-01

    The developing embryo is a remarkable example of self-organization, where functional units are created in a complex spatio-temporal choreography. Recently, human embryonic stem cells (ESCs) have been used to recapitulate in vitro the self-organization programs that are executed in the embryo in vivo. This represents a unique opportunity to address self-organization in humans that is otherwise not addressable with current technologies. In this essay, we review the recent literature on self-organization of human ESCs, with a particular focus on two examples: formation of embryonic germ layers and neural rosettes. Intriguingly, both activation and elimination of TGFβ signaling can initiate self-organization, albeit with different molecular underpinnings. We discuss the mechanisms underlying the formation of these structures in vitro and explore future challenges in the field. PMID:26970615

  3. The transformation suppressor gene Reck is required for postaxial patterning in mouse forelimbs

    Directory of Open Access Journals (Sweden)

    Mako Yamamoto

    2012-03-01

    The membrane-anchored metalloproteinase-regulator RECK has been characterized as a tumor suppressor. Here we report that mice with reduced Reck-expression show limb abnormalities including right-dominant, forelimb-specific defects in postaxial skeletal elements. The forelimb buds of low-Reck mutants have an altered dorsal ectoderm with reduced Wnt7a and Igf2 expression, and hypotrophy in two signaling centers (i.e., ZPA and AER that are essential for limb outgrowth and patterning. Reck is abundantly expressed in the anterior mesenchyme in normal limb buds; mesenchyme-specific Reck inactivation recapitulates the low-Reck phenotype; and some teratogens downregulate Reck in mesenchymal cells. Our findings illustrate a role for Reck in the mesenchymal-epithelial interactions essential for mammalian development.

  4. A biomimetic physiological model for human adipose tissue by adipocytes and endothelial cell cocultures with spatially controlled distribution

    International Nuclear Information System (INIS)

    Yao, Rui; Zhang, Renji; Lin, Feng; Du, Yanan; Luan, Jie

    2013-01-01

    An in vitro model that recapitulates the characteristics of native human adipose tissue would largely benefit pathology studies and therapy development. In this paper, we fabricated a physiological model composed of both human adipocytes and endothelial cells with spatially controlled distribution that biomimics the structure and composition of human adipose tissue. Detailed studies into the cell–cell interactions between the adipocytes and endothelial cells revealed a mutual-enhanced effect which resembles the in vivo routine. Furthermore, comparisons between planar coculture and model coculture demonstrated improved adipocyte function as well as endothelial cell proliferation under the same conditions. This research provided a reliable model for human adipose tissue development studies and potential obesity-related therapy development. (paper)

  5. WNT-mediated Modulation of Bone Metabolism: Implications for WNT Targeting to Treat Extraskeletal Disorders.

    Science.gov (United States)

    Bullock, Whitney A; Robling, Alexander G

    2017-10-01

    The WNT-signaling pathway is involved in cellular and tissue functions that control such diverse processes as body axis patterning, cellular proliferation, differentiation, and life span. The long list of molecules that can participate or modify WNT signaling makes this pathway one of the most complex in cell biology. In bone tissues, WNT signaling is required for proper skeletal development, and human mutations in various components of the cascade revealed insights into pharmacologic targeting that can be harnessed to improve skeletal health. In particular, mutations in genes that code for the WNT-signaling inhibitor sclerostin or the WNT coreceptor lipoprotein receptor-related protein 5 have highlighted the potential therapeutic value of recapitulating those effects in patients with low bone mass. A constant challenge in this area is selectively modifying WNT components in the tissue of interest, as WNT has manifold effects in nearly every tissue.

  6. Bioinspired Hydrogels to Engineer Cancer Microenvironments.

    Science.gov (United States)

    Park, Kyung Min; Lewis, Daniel; Gerecht, Sharon

    2017-06-21

    Recent research has demonstrated that tumor microenvironments play pivotal roles in tumor development and metastasis through various physical, chemical, and biological factors, including extracellular matrix (ECM) composition, matrix remodeling, oxygen tension, pH, cytokines, and matrix stiffness. An emerging trend in cancer research involves the creation of engineered three-dimensional tumor models using bioinspired hydrogels that accurately recapitulate the native tumor microenvironment. With recent advances in materials engineering, many researchers are developing engineered tumor models, which are promising platforms for the study of cancer biology and for screening of therapeutic agents for better clinical outcomes. In this review, we discuss the development and use of polymeric hydrogel materials to engineer native tumor ECMs for cancer research, focusing on emerging technologies in cancer engineering that aim to accelerate clinical outcomes.

  7. A nontranscriptional role for Oct4 in the regulation of mitotic entry

    Science.gov (United States)

    Zhao, Rui; Deibler, Richard W.; Lerou, Paul H.; Ballabeni, Andrea; Heffner, Garrett C.; Cahan, Patrick; Unternaehrer, Juli J.; Kirschner, Marc W.; Daley, George Q.

    2014-01-01

    Rapid progression through the cell cycle and a very short G1 phase are defining characteristics of embryonic stem cells. This distinct cell cycle is driven by a positive feedback loop involving Rb inactivation and reduced oscillations of cyclins and cyclin-dependent kinase (Cdk) activity. In this setting, we inquired how ES cells avoid the potentially deleterious consequences of premature mitotic entry. We found that the pluripotency transcription factor Oct4 (octamer-binding transcription factor 4) plays an unappreciated role in the ES cell cycle by forming a complex with cyclin–Cdk1 and inhibiting Cdk1 activation. Ectopic expression of Oct4 or a mutant lacking transcriptional activity recapitulated delayed mitotic entry in HeLa cells. Reduction of Oct4 levels in ES cells accelerated G2 progression, which led to increased chromosomal missegregation and apoptosis. Our data demonstrate an unexpected nontranscriptional function of Oct4 in the regulation of mitotic entry. PMID:25324523

  8. New lessons learned from disease modeling with induced Pluripotent Stem Cells

    Science.gov (United States)

    Onder, Tamer T.; Daley, George Q.

    2012-01-01

    Cellular reprogramming and generation of induced pluripotent stem cells (iPSCs) from adult cell types has enabled the creation of patient-specific stem cells for use in disease modeling. To date, many iPSC lines have been generated from a variety of disorders, which have then been differentiated into disease-relevant cell types. When a disease-specific phenotype is detectable in such differentiated cells, the reprogramming technology provides a new opportunity to identify aberrant disease-associated pathways and drugs that can block them. Here, we highlight recent progress as well as limitations in the use of iPSCs to recapitulate disease phenotypes and to screen for therapeutics in vitro. PMID:22749051

  9. Dissecting engineered cell types and enhancing cell fate conversion via CellNet

    Science.gov (United States)

    Morris, Samantha A.; Cahan, Patrick; Li, Hu; Zhao, Anna M.; San Roman, Adrianna K.; Shivdasani, Ramesh A.; Collins, James J.; Daley, George Q.

    2014-01-01

    SUMMARY Engineering clinically relevant cells in vitro holds promise for regenerative medicine, but most protocols fail to faithfully recapitulate target cell properties. To address this, we developed CellNet, a network biology platform that determines whether engineered cells are equivalent to their target tissues, diagnoses aberrant gene regulatory networks, and prioritizes candidate transcriptional regulators to enhance engineered conversions. Using CellNet, we improved B cell to macrophage conversion, transcriptionally and functionally, by knocking down predicted B cell regulators. Analyzing conversion of fibroblasts to induced hepatocytes (iHeps), CellNet revealed an unexpected intestinal program regulated by the master regulator Cdx2. We observed long-term functional engraftment of mouse colon by iHeps, thereby establishing their broader potential as endoderm progenitors and demonstrating direct conversion of fibroblasts into intestinal epithelium. Our studies illustrate how CellNet can be employed to improve direct conversion and to uncover unappreciated properties of engineered cells. PMID:25126792

  10. Bioprinting of 3D Convoluted Renal Proximal Tubules on Perfusable Chips

    Science.gov (United States)

    Homan, Kimberly A.; Kolesky, David B.; Skylar-Scott, Mark A.; Herrmann, Jessica; Obuobi, Humphrey; Moisan, Annie; Lewis, Jennifer A.

    2016-10-01

    Three-dimensional models of kidney tissue that recapitulate human responses are needed for drug screening, disease modeling, and, ultimately, kidney organ engineering. Here, we report a bioprinting method for creating 3D human renal proximal tubules in vitro that are fully embedded within an extracellular matrix and housed in perfusable tissue chips, allowing them to be maintained for greater than two months. Their convoluted tubular architecture is circumscribed by proximal tubule epithelial cells and actively perfused through the open lumen. These engineered 3D proximal tubules on chip exhibit significantly enhanced epithelial morphology and functional properties relative to the same cells grown on 2D controls with or without perfusion. Upon introducing the nephrotoxin, Cyclosporine A, the epithelial barrier is disrupted in a dose-dependent manner. Our bioprinting method provides a new route for programmably fabricating advanced human kidney tissue models on demand.

  11. Stress Effects on Multiple Memory System Interactions

    Directory of Open Access Journals (Sweden)

    Deborah Ness

    2016-01-01

    Full Text Available Extensive behavioural, pharmacological, and neurological research reports stress effects on mammalian memory processes. While stress effects on memory quantity have been known for decades, the influence of stress on multiple memory systems and their distinct contributions to the learning process have only recently been described. In this paper, after summarizing the fundamental biological aspects of stress/emotional arousal and recapitulating functionally and anatomically distinct memory systems, we review recent animal and human studies exploring the effects of stress on multiple memory systems. Apart from discussing the interaction between distinct memory systems in stressful situations, we will also outline the fundamental role of the amygdala in mediating such stress effects. Additionally, based on the methods applied in the herein discussed studies, we will discuss how memory translates into behaviour.

  12. Using the mouse to model human disease: increasing validity and reproducibility

    Directory of Open Access Journals (Sweden)

    Monica J. Justice

    2016-02-01

    Full Text Available Experiments that use the mouse as a model for disease have recently come under scrutiny because of the repeated failure of data, particularly derived from preclinical studies, to be replicated or translated to humans. The usefulness of mouse models has been questioned because of irreproducibility and poor recapitulation of human conditions. Newer studies, however, point to bias in reporting results and improper data analysis as key factors that limit reproducibility and validity of preclinical mouse research. Inaccurate and incomplete descriptions of experimental conditions also contribute. Here, we provide guidance on best practice in mouse experimentation, focusing on appropriate selection and validation of the model, sources of variation and their influence on phenotypic outcomes, minimum requirements for control sets, and the importance of rigorous statistics. Our goal is to raise the standards in mouse disease modeling to enhance reproducibility, reliability and clinical translation of findings.

  13. Research program on radioactive wastes - Overview report for 2011

    International Nuclear Information System (INIS)

    Brander, S.

    2012-01-01

    This report for the Swiss Federal Office of Energy (SFOE) summarises the program's main points of interest and the work done in the year 2011 along with the results obtained. The aims of the program are recapitulated. The research program is co-ordinated by a working group comprising the Swiss Federal Office of Energy, the Swiss Federal Nuclear Safety Inspectorate ENSI, the Commission on Nuclear Waste Disposal and the Commission for Safety in Nuclear Installations, Some highlights of the research program are briefly described and discussed. Topics covered concern the marking of nuclear waste repositories, value judgement and opinion building, waste management as well as repository design, including dimensioning and monitoring systems, National and international co-operation is also discussed

  14. Deficient incorporation of spike protein into virions contributes to the lack of infectivity following establishment of a persistent, non-productive infection in oligodendroglial cell culture by murine coronavirus

    International Nuclear Information System (INIS)

    Liu Yin; Herbst, Werner; Cao Jianzhong; Zhang Xuming

    2011-01-01

    Infection of mouse oligodendrocytes with a recombinant mouse hepatitis virus (MHV) expressing a green fluorescence protein facilitated specific selection of virus-infected cells and subsequent establishment of persistence. Interestingly, while viral genomic RNAs persisted in infected cells over 14 subsequent passages with concomitant synthesis of viral subgenomic mRNAs and structural proteins, no infectious virus was isolated beyond passage 2. Further biochemical and electron microscopic analyses revealed that virions, while assembled, contained little spike in the envelope, indicating that lack of infectivity during persistence was likely due to deficiency in spike incorporation. This type of non-lytic, non-productive persistence in oligodendrocytes is unique among animal viruses and resembles MHV persistence previously observed in the mouse central nervous system. Thus, establishment of such a culture system that can recapitulate the in vivo phenomenon will provide a powerful approach for elucidating the mechanisms of coronavirus persistence in glial cells at the cellular and molecular levels.

  15. Volta-Based Cells Materials Chemical Multiple Representation to Improve Ability of Student Representation

    Science.gov (United States)

    Helsy, I.; Maryamah; Farida, I.; Ramdhani, M. A.

    2017-09-01

    This study aimed to describe the application of teaching materials, analyze the increase in the ability of students to connect the three levels of representation and student responses after application of multiple representations based teaching materials chemistry. The method used quasi one-group pretest-posttest design to 71 students. The results showed the application of teaching materials carried 88% with very good category. A significant increase ability to connect the three levels of representation of students after the application of multiple representations based teaching materials chemistry with t-value > t-crit (11.402 > 1.991). Recapitulation N-gain pretest and posttest showed relatively similar for all groups is 0.6 criterion being achievement. Students gave a positive response to the application of multiple representations based teaching materials chemistry. Students agree teaching materials used in teaching chemistry (88%), and agrees teaching materials to provide convenience in connecting the three levels of representation (95%).

  16. Dispersion Forces

    CERN Document Server

    Buhmann, Stefan Yoshi

    2012-01-01

    In this book, a modern unified theory of dispersion forces on atoms and bodies is presented which covers a broad range of advanced aspects and scenarios. Macroscopic quantum electrodynamics is shown to provide a powerful framework for dispersion forces which allows for discussing general properties like their non-additivity and the relation between microscopic and macroscopic interactions. It is demonstrated how the general results can be used to obtain dispersion forces on atoms in the presence of bodies of various shapes and materials. Starting with a brief recapitulation of volume I, this volume II deals especially with bodies of irregular shapes, universal scaling laws, dynamical forces on excited atoms, enhanced forces in cavity quantum electrodynamics, non-equilibrium forces in thermal environments and quantum friction. The book gives both the specialist and those new to the field a thorough overview over recent results in the field. It provides a toolbox for studying dispersion forces in various contex...

  17. Animal models for Gaucher disease research

    Directory of Open Access Journals (Sweden)

    Tamar Farfel-Becker

    2011-11-01

    Full Text Available Gaucher disease (GD, the most common lysosomal storage disorder (LSD, is caused by the defective activity of the lysosomal hydrolase glucocerebrosidase, which is encoded by the GBA gene. Generation of animal models that faithfully recapitulate the three clinical subtypes of GD has proved to be more of a challenge than first anticipated. The first mouse to be produced died within hours after birth owing to skin permeability problems, and mice with point mutations in Gba did not display symptoms correlating with human disease and also died soon after birth. Recently, conditional knockout mice that mimic some features of the human disease have become available. Here, we review the contribution of all currently available animal models to examining pathological pathways underlying GD and to testing the efficacy of new treatment modalities, and propose a number of criteria for the generation of more appropriate animal models of GD.

  18. Microfluidic 3D cell culture: potential application for tissue-based bioassays

    Science.gov (United States)

    Li, XiuJun (James); Valadez, Alejandra V.; Zuo, Peng; Nie, Zhihong

    2014-01-01

    Current fundamental investigations of human biology and the development of therapeutic drugs, commonly rely on two-dimensional (2D) monolayer cell culture systems. However, 2D cell culture systems do not accurately recapitulate the structure, function, physiology of living tissues, as well as highly complex and dynamic three-dimensional (3D) environments in vivo. The microfluidic technology can provide micro-scale complex structures and well-controlled parameters to mimic the in vivo environment of cells. The combination of microfluidic technology with 3D cell culture offers great potential for in vivo-like tissue-based applications, such as the emerging organ-on-a-chip system. This article will review recent advances in microfluidic technology for 3D cell culture and their biological applications. PMID:22793034

  19. Microfluidic Organ/Body-on-a-Chip Devices at the Convergence of Biology and Microengineering

    Science.gov (United States)

    Perestrelo, Ana Rubina; Águas, Ana C. P.; Rainer, Alberto; Forte, Giancarlo

    2015-01-01

    Recent advances in biomedical technologies are mostly related to the convergence of biology with microengineering. For instance, microfluidic devices are now commonly found in most research centers, clinics and hospitals, contributing to more accurate studies and therapies as powerful tools for drug delivery, monitoring of specific analytes, and medical diagnostics. Most remarkably, integration of cellularized constructs within microengineered platforms has enabled the recapitulation of the physiological and pathological conditions of complex tissues and organs. The so-called “organ-on-a-chip” technology, which represents a new avenue in the field of advanced in vitro models, with the potential to revolutionize current approaches to drug screening and toxicology studies. This review aims to highlight recent advances of microfluidic-based devices towards a body-on-a-chip concept, exploring their technology and broad applications in the biomedical field. PMID:26690442

  20. Bovine annulus fibrosus cell lines isolated from intervertebral discs

    Directory of Open Access Journals (Sweden)

    Petra Kraus

    2016-12-01

    Full Text Available The adult bovine (Bos taurus intervertebral disc is primarily comprised of two major tissue types: The outer annulus fibrosus (AF and the central nucleus pulposus (NP. We isolated several primary cell lineages of passage (P 0 cells from the AF tissue omitting typically used enzymatic tissue digestion protocols. The cells grow past p10 without signs of senescence in DMEM + 10% FCS on 0.1% gelatin coated/uncoated surfaces of standard cell culture plates and survive freeze-thawing. Preliminary analysis of the AF derived cells for expression of the two structural genes Col1a1 and Col2a1 was performed by PISH recapitulating the expression observed in vivo.