WorldWideScience

Sample records for gigyf2 gene disruption

  1. Conversion of homothallic yeast to heterothallism trough HO gene disruption

    CSIR Research Space (South Africa)

    Van Zyl, WH

    1993-04-01

    Full Text Available A simple method was developed for the conversion of homothallic Saccharomyces cerevisiae yeaststrains to heterothallism through HO gene disruption. An integrative ho:: neo disrupted allele was constructed by cloning a dominant selectable marker...

  2. Problem-Solving Test: Targeted Gene Disruption

    Science.gov (United States)

    Szeberenyi, Jozsef

    2008-01-01

    Mutational inactivation of a specific gene is the most powerful technique to analyze the biological function of the gene. This approach has been used for a long time in viruses, bacteria, yeast, and fruit fly, but looked quite hopeless in more complex organisms. Targeted inactivation of specific genes (also known as knock-out mutation) in mice is…

  3. Functional Analysis of an ATP-Binding Cassette Transporter Gene in Botrytis cinerea by Gene Disruption

    OpenAIRE

    Masami, NAKAJIMA; Junko, SUZUKI; Takehiko, HOSAKA; Tadaaki, HIBI; Katsumi, AKUTSU; School of Agriculture, Ibaraki University; School of Agriculture, Ibaraki University; School of Agriculture, Ibaraki University; Department of Agriculture and Environmental Biology, The University of Tokyo; School of Agriculture, Ibaraki University

    2001-01-01

    The BMR1 gene encoding an ABC transporter was cloned from Botrytis cinerea. To examine the function of BMR1 in B.cinerea, we isolated BMR1-deficient mutants after gene disruption. Disruption vector pBcDF4 was constructed by replacing the BMR1-coding region with a hygromycin B phosphotransferase gene(hph)cassette. The BMR1 disruptants had an increased sensitivity to polyoxin and iprobenfos. Polyoxin and iprobenfos, structurally unrelated compounds, may therefore be substrates of BMR1.

  4. Circadian Disruption Changes Gut Microbiome Taxa and Functional Gene Composition.

    Science.gov (United States)

    Deaver, Jessica A; Eum, Sung Y; Toborek, Michal

    2018-01-01

    Disrupted circadian rhythms and alterations of the gut microbiome composition were proposed to affect host health. Therefore, the aim of this research was to identify whether these events are connected and if circadian rhythm disruption by abnormal light-dark (LD) cycles affects microbial community gene expression and host vulnerability to intestinal dysfunction. Mice were subjected to either a 4-week period of constant 24-h light or of normal 12-h LD cycles. Stool samples were collected at the beginning and after the circadian rhythm disruption. A metatranscriptomic analysis revealed an increase in Ruminococcus torques , a bacterial species known to decrease gut barrier integrity, and a decrease in Lactobacillus johnsonii , a bacterium that helps maintain the intestinal epithelial cell layer, after circadian rhythm disruption. In addition, genes involved in pathways promoting host beneficial immune responses were downregulated, while genes involved in the synthesis and transportation of the endotoxin lipopolysaccharide were upregulated in mice with disrupted circadian cycles. Importantly, these mice were also more prone to dysfunction of the intestinal barrier. These results further elucidate the impact of light-cycle disruption on the gut microbiome and its connection with increased incidence of disease in response to circadian rhythm disturbances.

  5. Gene disruption in Salmonella typhimurim by modified λ Red disruption system.

    Science.gov (United States)

    Ahani Azari, A; Zahraei Salehi, T; Nayeri Fasaei, B; Alebouyeh, M

    2015-01-01

    There are many techniques to knock out directed genes in bacteria, some of which have been described in Salmonella species. In this study, a combination of SOEing PCR method and the λ Red disruption system were used to disrupt phoP gene in wild type and standard strains of Salmonella typhimurium. Three standards PCR and one fusion PCR reactions were performed to construct a linear DNA including upstream and downstream of phoP gene and Kanamycin cassette. As a template plasmid, we used pKD4 which carries kanamycin gene flanked by FRT (FLP recognition target) sites. The resulting construct was electroporated into prepared competent cells of S. typhimurium. The transformants colonies related to the standard strain appeared on the LB-Km-agar plates after incubation, but there was no colony on LB-Km-agar plates corresponding to the wild type strain. The failure in transformation of the wild type strain may be because of inflexibility of the λ Red disruption system in this strain or its unique restriction-modification system. However, by this construct we are able to generate phoP mutant in many of the Salmonella species due to high homology of the phoP gene which exists in different species.

  6. A new type of gene-disruption cassette with a rescue gene for Pichia pastoris.

    Science.gov (United States)

    Shibui, Tatsuro; Hara, Hiroyoshi

    2017-09-01

    Pichia pastoris has been used for the production of many recombinant proteins, and many useful mutant strains have been created. However, the efficiency of mutant isolation by gene-targeting is usually low and the procedure is difficult for those inexperienced in yeast genetics. In order to overcome these issues, we developed a new gene-disruption system with a rescue gene using an inducible Cre/mutant-loxP system. With only short homology regions, the gene-disruption cassette of the system replaces its target-gene locus containing a mutation with a compensatory rescue gene. As the cassette contains the AOX1 promoter-driven Cre gene, when targeted strains are grown on media containing methanol, the DNA fragment, i.e., the marker, rescue and Cre genes, between the mutant-loxP sequences in the cassette is excised, leaving only the remaining mutant-loxP sequence in the genome, and consequently a target gene-disrupted mutant can be isolated. The system was initially validated on ADE2 gene disruption, where the disruption can easily be detected by color-change of the colonies. Then, the system was applied for knocking-out URA3 and OCH1 genes, reported to be difficult to accomplish by conventional gene-targeting methods. All three gene-disruption cassettes with their rescue genes replaced their target genes, and the Cre/mutant-loxP system worked well to successfully isolate their knock-out mutants. This study identified a new gene-disruption system that could be used to effectively and strategically knock out genes of interest, especially whose deletion is detrimental to growth, without using special strains, e.g., deficient in nonhomologous end-joining, in P. pastoris. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1201-1208, 2017. © 2017 American Institute of Chemical Engineers.

  7. Disruption of the neurexin 1 gene is associated with schizophrenia

    DEFF Research Database (Denmark)

    Rujescu, Dan; Ingason, Andres; Cichon, Sven

    2009-01-01

    may vary according to the level of functional impact on the gene, we next restricted the association analysis to CNVs that disrupt exons (0.24% of cases and 0.015% of controls). These were significantly associated with a high odds ratio (P = 0.0027; OR 8.97, 95% CI 1.8-51.9). We conclude that NRXN1...

  8. The BDGP gene disruption project: Single transposon insertions associated with 40 percent of Drosophila genes

    Energy Technology Data Exchange (ETDEWEB)

    Bellen, Hugo J.; Levis, Robert W.; Liao, Guochun; He, Yuchun; Carlson, Joseph W.; Tsang, Garson; Evans-Holm, Martha; Hiesinger, P. Robin; Schulze, Karen L.; Rubin, Gerald M.; Hoskins, Roger A.; Spradling, Allan C.

    2004-01-13

    The Berkeley Drosophila Genome Project (BDGP) strives to disrupt each Drosophila gene by the insertion of a single transposable element. As part of this effort, transposons in more than 30,000 fly strains were localized and analyzed relative to predicted Drosophila gene structures. Approximately 6,300 lines that maximize genomic coverage were selected to be sent to the Bloomington Stock Center for public distribution, bringing the size of the BDGP gene disruption collection to 7,140 lines. It now includes individual lines predicted to disrupt 5,362 of the 13,666 currently annotated Drosophila genes (39 percent). Other lines contain an insertion at least 2 kb from others in the collection and likely mutate additional incompletely annotated or uncharacterized genes and chromosomal regulatory elements. The remaining strains contain insertions likely to disrupt alternative gene promoters or to allow gene mis-expression. The expanded BDGP gene disruption collection provides a public resource that will facilitate the application of Drosophila genetics to diverse biological problems. Finally, the project reveals new insight into how transposons interact with a eukaryotic genome and helps define optimal strategies for using insertional mutagenesis as a genomic tool.

  9. Disruption?

    DEFF Research Database (Denmark)

    2016-01-01

    This is a short video on the theme disruption and entrepreneurship. It takes the form of an interview with John Murray......This is a short video on the theme disruption and entrepreneurship. It takes the form of an interview with John Murray...

  10. Targeted disruption of the mouse Lipoma Preferred Partner gene

    International Nuclear Information System (INIS)

    Vervenne, Hilke B.V.K.; Crombez, Koen R.M.O.; Delvaux, Els L.; Janssens, Veerle; Ven, Wim J.M. van de; Petit, Marleen M.R.

    2009-01-01

    LPP (Lipoma Preferred Partner) is a zyxin-related cell adhesion protein that is involved in the regulation of cell migration. We generated mice with a targeted disruption of the Lpp gene and analysed the importance of Lpp for embryonic development and adult functions. Aberrant Mendelian inheritance in heterozygous crosses suggested partial embryonic lethality of Lpp -/- females. Fertility of Lpp -/- males was proven to be normal, however, females from Lpp -/- x Lpp -/- crosses produced a strongly reduced number of offspring, probably due to a combination of female embryonic lethality and aberrant pregnancies. Apart from these developmental and reproductive abnormalities, Lpp -/- mice that were born reached adulthood without displaying any additional macroscopic defects. On the other hand, Lpp -/- mouse embryonic fibroblasts exhibited reduced migration capacity, reduced viability, and reduced expression of some Lpp interaction partners. Finally, we discovered a short nuclear form of Lpp, expressed mainly in testis via an alternative promoter.

  11. Gene Disruption in Scedosporium aurantiacum: Proof of Concept with the Disruption of SODC Gene Encoding a Cytosolic Cu,Zn-Superoxide Dismutase.

    Science.gov (United States)

    Pateau, Victoire; Razafimandimby, Bienvenue; Vandeputte, Patrick; Thornton, Christopher R; Guillemette, Thomas; Bouchara, Jean-Philippe; Giraud, Sandrine

    2018-02-01

    Scedosporium species are opportunistic pathogens responsible for a large variety of infections in humans. An increasing occurrence was observed in patients with underlying conditions such as immunosuppression or cystic fibrosis. Indeed, the genus Scedosporium ranks the second among the filamentous fungi colonizing the respiratory tracts of the CF patients. To date, there is very scarce information on the pathogenic mechanisms, at least in part because of the limited genetic tools available. In the present study, we successfully developed an efficient transformation and targeted gene disruption approach on the species Scedosporium aurantiacum. The disruption cassette was constructed using double-joint PCR procedure, and resistance to hygromycin B as the selection marker. This proof of concept was performed on the functional gene SODC encoding the Cu,Zn-superoxide dismutase. Disruption of the SODC gene improved susceptibility of the fungus to oxidative stress. This technical advance should open new research areas and help to better understand the biology of Scedosporium species.

  12. Directed mutagenesis in Candida albicans: one-step gene disruption to isolate ura3 mutants

    International Nuclear Information System (INIS)

    Kelly, R.; Miller, S.M.; Kurtz, M.B.; Kirsch, D.R.

    1987-01-01

    A method for introducing specific mutations into the diploid Candida albicans by one-step gene disruption and subsequent UV-induced recombination was developed. The cloned C. albicans URA3 gene was disrupted with the C. albicans ADE2 gene, and the linearized DNA was used for transformation of two ade2 mutants, SGY-129 and A81-Pu. Both an insertional inactivation of the URA3 gene and a disruption which results in a 4.0-kilobase deletion were made. Southern hybridization analyses demonstrated that the URA3 gene was disrupted on one of the chromosomal homologs in 15 of the 18 transformants analyzed. These analyses also revealed restriction site dimorphism of EcoRI at the URA3 locus which provides a unique marker to distinguish between chromosomal homologs. This enabled us to show that either homolog could be disrupted and that disrupted transformants of SGY-129 contained more than two copies of the URA3 locus. The A81-Pu transformants heterozygous for the ura3 mutations were rendered homozygous and Ura- by UV-induced recombination. The homozygosity of a deletion mutant and an insertion mutant was confirmed by Southern hybridization. Both mutants were transformed to Ura+ with plasmids containing the URA3 gene and in addition, were resistant to 5-fluoro-orotic acid, a characteristic of Saccharomyces cerevisiae ura3 mutants as well as of orotidine-5'-phosphate decarboxylase mutants of other organisms

  13. SYBR safeTM efficiently replaces ethidium bromide in Aspergillus fumigatus gene disruption.

    Science.gov (United States)

    Canela, H M S; Takami, L A; Ferreira, M E S

    2017-02-08

    Invasive aspergillosis is a disease responsible for high mortality rates, caused mainly by Aspergillus fumigatus. The available drugs are limited and this disease continues to occur at an unacceptable frequency. Gene disruption is essential in the search for new drug targets. An efficient protocol for A. fumigatus gene disruption was described but it requires ethidium bromide, a genotoxic agent, for DNA staining. Therefore, the present study tested SYBR safe TM , a non-genotoxic DNA stain, in A. fumigatus gene disruption protocol. The chosen gene was cipC, which has already been disrupted successfully in our laboratory. A deletion cassette was constructed in Saccharomyces cerevisiae and used in A. fumigatus transformation. There was no statistical difference between the tested DNA stains. The success rate of S. cerevisiae transformation was 63.3% for ethidium bromide and 70% for SYBR safe TM . For A. fumigatus gene disruption, the success rate for ethidium bromide was 100 and 97% for SYBR safe TM . In conclusion, SYBR safe TM efficiently replaced ethidium bromide, making this dye a safe and efficient alternative for DNA staining in A. fumigatus gene disruption.

  14. Isolation of industrial strains of Aspergillus oryzae lacking ferrichrysin by disruption of the dffA gene.

    Science.gov (United States)

    Watanabe, Hisayuki; Hatakeyama, Makoto; Sakurai, Hiroshi; Uchimiya, Hirofumi; Sato, Toshitsugu

    2008-11-01

    Based on studies using laboratory strains, the efficiency of gene disruption in Aspergillus oryzae, commonly known as koji mold, is low; thus, gene disruption has rarely been applied to the breeding of koji mold. To evaluate the efficiency of gene disruption in industrial strains of A. oryzae, we produced ferrichrysin biosynthesis gene (dffA) disruptants using three different industrial strains as hosts. PCR analysis of 438 pyrithiamine-resistant transformants showed dffA gene disruption efficiency of 42.9%-64.1%, which is much higher than previously reported. Analysis of the physiological characteristics of the disruptants indicated that dffA gene disruption results in hypersensitivity to hydrogen peroxide. To investigate the industrial characteristics of dffA gene disruptants, two strains were used to make rice koji and their properties were compared to those of the host strains. No differences were found between the dffA gene disruptants and the host strains, except that the disruptants did not produce ferrichrysin. Thus, this gene disruption technique is much more effective than conventional mutagenesis for A. oryzae breeding.

  15. Disruption of the neurexin 1 gene is associated with schizophrenia.

    NARCIS (Netherlands)

    Rujescu, D.; Ingason, A.; Cichon, S.; Pietilainen, O.P.H.; Barnes, M.R.; Toulopoulou, T.; Picchioni, M.; Vassos, E.; Ettinger, U.; Bramon, E.; Murray, R.; Ruggeri, M.; Tosato, S.; Bonetto, C.; Steinberg, S.; Sigurdsson, E.; Sigmundsson, T.; Petursson, H.; Gylfason, A; Olason, P.; Hardarsson, G.; Jonsdottir, G.A.; Gustafsson, O.; Fossdal, R.; Giegling, I.; Moller, H.J.; Hartmann, A.M.; Hoffmann, P.; Crombie, C.; Fraser, G.; Walker, N.; Lonnqvist, J.; Suvisaari, J.; Tuulio-Henriksson, A.; Djurovic, S.; Melle, I.; Andreassen, O.A.; Hansen, T.; Werge, T.; Kiemeney, L.A.L.M.; Franke, B.; Veltman, J.A.; Buizer-Voskamp, J.E.; Sabatti, C.; Ophoff, R.A.; Rietschel, M.; Nothen, Markus; Stefansson, K.; Peltonen, L.; St Clair, D.; Stefansson, H.; Collier, D.A.

    2009-01-01

    Deletions within the neurexin 1 gene (NRXN1; 2p16.3) are associated with autism and have also been reported in two families with schizophrenia. We examined NRXN1, and the closely related NRXN2 and NRXN3 genes, for copy number variants (CNVs) in 2977 schizophrenia patients and 33 746 controls from

  16. Disruption of the neurexin 1 gene is associated with schizophrenia

    NARCIS (Netherlands)

    Rujescu, Dan; Ingason, Andres; Cichon, Sven; Pietilainen, Olli P. H.; Barnes, Michael R.; Toulopoulou, Timothea; Picchioni, Marco; Vassos, Evangelos; Ettinger, Ulrich; Bramon, Elvira; Murray, Robin; Ruggeri, Mirella; Tosato, Sarah; Bonetto, Chiara; Steinberg, Stacy; Sigurdsson, Engilbert; Sigmundsson, Thordur; Petursson, Hannes; Gylfason, Arnaldur; Olason, Pall I.; Hardarsson, Gudmundur; Jonsdottir, Gudrun A.; Gustafsson, Omar; Fossdal, Ragnheidur; Giegling, Ina; Moeller, Hans-Jurgen; Hartmann, Annette M.; Hoffmann, Per; Crombie, Caroline; Fraser, Gillian; Walker, Nicholas; Lonnqvist, Jouko; Suvisaari, Jaana; Tuulio-Henriksson, Annamari; Djurovic, Srdjan; Melle, Ingrid; Andreassen, Ole A.; Hansen, Thomas; Werge, Thomas; Kiemeney, Lambertus A.; Franke, Barbara; Veltman, Joris; Buizer-Voskamp, Jacobine E.; Sabatti, Chiara; Ophoff, Roel A.; Rietschel, Marcella; Noehen, Markus M.; Stefansson, Kari; Peltonen, Leena; St Clair, David

    2009-01-01

    Deletions within the neurexin 1 gene (NRXN1; 2p16.3) are associated with autism and have also been reported in two families with schizophrenia. We examined NRXN1, and the closely related NRXN2 and NRXN3 genes, for copy number variants (CNVs) in 2977 schizophrenia patients and 33 746 controls from

  17. Synaptic, transcriptional and chromatin genes disrupted in autism.

    Science.gov (United States)

    De Rubeis, Silvia; He, Xin; Goldberg, Arthur P; Poultney, Christopher S; Samocha, Kaitlin; Cicek, A Erucment; Kou, Yan; Liu, Li; Fromer, Menachem; Walker, Susan; Singh, Tarinder; Klei, Lambertus; Kosmicki, Jack; Shih-Chen, Fu; Aleksic, Branko; Biscaldi, Monica; Bolton, Patrick F; Brownfeld, Jessica M; Cai, Jinlu; Campbell, Nicholas G; Carracedo, Angel; Chahrour, Maria H; Chiocchetti, Andreas G; Coon, Hilary; Crawford, Emily L; Curran, Sarah R; Dawson, Geraldine; Duketis, Eftichia; Fernandez, Bridget A; Gallagher, Louise; Geller, Evan; Guter, Stephen J; Hill, R Sean; Ionita-Laza, Juliana; Jimenz Gonzalez, Patricia; Kilpinen, Helena; Klauck, Sabine M; Kolevzon, Alexander; Lee, Irene; Lei, Irene; Lei, Jing; Lehtimäki, Terho; Lin, Chiao-Feng; Ma'ayan, Avi; Marshall, Christian R; McInnes, Alison L; Neale, Benjamin; Owen, Michael J; Ozaki, Noriio; Parellada, Mara; Parr, Jeremy R; Purcell, Shaun; Puura, Kaija; Rajagopalan, Deepthi; Rehnström, Karola; Reichenberg, Abraham; Sabo, Aniko; Sachse, Michael; Sanders, Stephan J; Schafer, Chad; Schulte-Rüther, Martin; Skuse, David; Stevens, Christine; Szatmari, Peter; Tammimies, Kristiina; Valladares, Otto; Voran, Annette; Li-San, Wang; Weiss, Lauren A; Willsey, A Jeremy; Yu, Timothy W; Yuen, Ryan K C; Cook, Edwin H; Freitag, Christine M; Gill, Michael; Hultman, Christina M; Lehner, Thomas; Palotie, Aaarno; Schellenberg, Gerard D; Sklar, Pamela; State, Matthew W; Sutcliffe, James S; Walsh, Christiopher A; Scherer, Stephen W; Zwick, Michael E; Barett, Jeffrey C; Cutler, David J; Roeder, Kathryn; Devlin, Bernie; Daly, Mark J; Buxbaum, Joseph D

    2014-11-13

    The genetic architecture of autism spectrum disorder involves the interplay of common and rare variants and their impact on hundreds of genes. Using exome sequencing, here we show that analysis of rare coding variation in 3,871 autism cases and 9,937 ancestry-matched or parental controls implicates 22 autosomal genes at a false discovery rate (FDR) < 0.05, plus a set of 107 autosomal genes strongly enriched for those likely to affect risk (FDR < 0.30). These 107 genes, which show unusual evolutionary constraint against mutations, incur de novo loss-of-function mutations in over 5% of autistic subjects. Many of the genes implicated encode proteins for synaptic formation, transcriptional regulation and chromatin-remodelling pathways. These include voltage-gated ion channels regulating the propagation of action potentials, pacemaking and excitability-transcription coupling, as well as histone-modifying enzymes and chromatin remodellers-most prominently those that mediate post-translational lysine methylation/demethylation modifications of histones.

  18. Sites of disruption within E1 and E2 genes of HPV16 and association with cervical dysplasia.

    Science.gov (United States)

    Tsakogiannis, D; Gortsilas, P; Kyriakopoulou, Z; Ruether, I G A; Dimitriou, T G; Orfanoudakis, G; Markoulatos, P

    2015-11-01

    Integration of HPV16 DNA into the host chromosome usually disrupts the E1 and/or E2 genes. The present study investigated the disruption of E1, E2 genes in a total of eighty four HPV16-positive precancerous and cervical cancer specimens derived from Greek women (seventeen paraffin-embedded cervical biopsies and sixty seven Thin Prep samples). Complete E2 and E1 genes were amplified using three and nine overlapping primer sets respectively, in order to define the sites of disruption. Extensive mapping analysis revealed that disruption/deletion events within E2 gene occurred in high grade and cervical cancer samples (x(2) test, P disruption was documented among low grade cervical intraepithelial neoplasias. In addition, disruptions within the E1 gene occur both in high and low grade cervical intraepithelial neoplasia. This leads to the assumption that in low grade cervical intraepithelial neoplasias only E1 gene disruption was involved (Fisher's exact test, P disruption of E1 gene was located between nucleotides 1059 and 1323, while the most prevalent deleted region of the E2 gene was located between nucleotides 3172 and 3649 (E2 hinge region). Therefore, it is proposed that each population has its own profile of frequencies and sites of disruptions and extensive mapping analysis of E1 and E2 genes is mandatory in order to determine suitable markers for HPV16 DNA integration analysis in distinct populations. © 2015 Wiley Periodicals, Inc.

  19. New Clox Systems for rapid and efficient gene disruption in Candida albicans.

    Directory of Open Access Journals (Sweden)

    Shahida Shahana

    Full Text Available Precise genome modification is essential for the molecular dissection of Candida albicans, and is yielding invaluable information about the roles of specific gene functions in this major fungal pathogen of humans. C. albicans is naturally diploid, unable to undergo meiosis, and utilizes a non-canonical genetic code. Hence, specialized tools have had to be developed for gene disruption in C. albicans that permit the deletion of both target alleles, and in some cases, the recycling of the Candida-specific selectable markers. Previously, we developed a tool based on the Cre recombinase, which recycles markers in C. albicans with 90-100% efficiency via site-specific recombination between loxP sites. Ironically, the utility of this system was hampered by the extreme efficiency of Cre, which prevented the construction in Escherichia coli of stable disruption cassettes carrying a methionine-regulatable CaMET3p-cre gene flanked by loxP sites. Therefore, we have significantly enhanced this system by engineering new Clox cassettes that carry a synthetic, intron-containing cre gene. The Clox kit facilitates efficient transformation and marker recycling, thereby simplifying and accelerating the process of gene disruption in C. albicans. Indeed, homozygous mutants can be generated and their markers resolved within two weeks. The Clox kit facilitates strategies involving single marker recycling or multi-marker gene disruption. Furthermore, it includes the dominant NAT1 marker, as well as URA3, HIS1 and ARG4 cassettes, thereby permitting the manipulation of clinical isolates as well as genetically marked strains of C. albicans. The accelerated gene disruption strategies afforded by this new Clox system are likely to have a profound impact on the speed with which C. albicans pathobiology can be dissected.

  20. Efficient disruption of endogenous Bombyx gene by TAL effector nucleases

    Czech Academy of Sciences Publication Activity Database

    Sajwan, Suresh; Takasu, Y.; Tamura, T.; Uchino, K.; Sezutsu, H.; Žurovec, Michal

    2013-01-01

    Roč. 43, č. 1 (2013), s. 17-23 ISSN 0965-1748 R&D Projects: GA ČR GAP305/10/2406 Grant - others:Japan Society for the Promotion of Science(JP) 23580083 Institutional support: RVO:60077344 Keywords : gene targeting * ZFN * nonhomologous end joining Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.420, year: 2013 http://www.sciencedirect.com/science/article/pii/S0965174812001622#

  1. Disruption of ten protease genes in the filamentous fungus Aspergillus oryzae highly improves production of heterologous proteins.

    Science.gov (United States)

    Yoon, Jaewoo; Maruyama, Jun-ichi; Kitamoto, Katsuhiko

    2011-02-01

    Proteolytic degradation by secreted proteases into the culture medium is one of the significant problems to be solved in heterologous protein production by filamentous fungi including Aspergillus oryzae. Double (tppA, and pepE) and quintuple (tppA, pepE, nptB, dppIV, and dppV) disruption of protease genes enhanced human lysozyme (HLY) and bovine chymosin (CHY) production by A. oryzae. In this study, we used a quintuple protease gene disruptant and performed successive rounds of disruption for five additional protease genes (alpA, pepA, AopepAa, AopepAd, and cpI), which were previously investigated by DNA microarray analyses for their expression. Gene disruption was performed by pyrG marker recycling with a highly efficient gene-targeting background (∆ligD) as previously reported. As a result, the maximum yields of recombinant CHY and HLY produced by a decuple protease gene disruptant were approximately 30% and 35%, respectively, higher than those produced by a quintuple protease gene disruptant. Thus, we successfully constructed a decuple protease gene disruptant possessing highly improved capability of heterologous protein production. This is the first report on decuple protease gene disruption that improved the levels of heterologous protein production by the filamentous fungus A. oryzae.

  2. Gene disruptions using P transposable elements: an integral component of the Drosophila genome project.

    OpenAIRE

    Spradling, A C; Stern, D M; Kiss, I; Roote, J; Laverty, T; Rubin, G M

    1995-01-01

    Biologists require genetic as well as molecular tools to decipher genomic information and ultimately to understand gene function. The Berkeley Drosophila Genome Project is addressing these needs with a massive gene disruption project that uses individual, genetically engineered P transposable elements to target open reading frames throughout the Drosophila genome. DNA flanking the insertions is sequenced, thereby placing an extensive series of genetic markers on the physical genomic map and a...

  3. Gene Expression Profiling Identifies Important Genes Affected by R2 Compound Disrupting FAK and P53 Complex

    International Nuclear Information System (INIS)

    Golubovskaya, Vita M.; Ho, Baotran; Conroy, Jeffrey; Liu, Song; Wang, Dan; Cance, William G.

    2014-01-01

    Focal Adhesion Kinase (FAK) is a non-receptor kinase that plays an important role in many cellular processes: adhesion, proliferation, invasion, angiogenesis, metastasis and survival. Recently, we have shown that Roslin 2 or R2 (1-benzyl-15,3,5,7-tetraazatricyclo[3.3.1.1~3,7~]decane) compound disrupts FAK and p53 proteins, activates p53 transcriptional activity, and blocks tumor growth. In this report we performed a microarray gene expression analysis of R2-treated HCT116 p53 +/+ and p53 −/− cells and detected 1484 genes that were significantly up- or down-regulated (p < 0.05) in HCT116 p53 +/+ cells but not in p53 −/− cells. Among up-regulated genes in HCT p53 +/+ cells we detected critical p53 targets: Mdm-2, Noxa-1, and RIP1. Among down-regulated genes, Met, PLK2, KIF14, BIRC2 and other genes were identified. In addition, a combination of R2 compound with M13 compound that disrupts FAK and Mmd-2 complex or R2 and Nutlin-1 that disrupts Mdm-2 and p53 decreased clonogenicity of HCT116 p53 +/+ colon cancer cells more significantly than each agent alone in a p53-dependent manner. Thus, the report detects gene expression profile in response to R2 treatment and demonstrates that the combination of drugs targeting FAK, Mdm-2, and p53 can be a novel therapy approach

  4. Gene expression disruptions of organism versus organ in Drosophila species hybrids.

    Directory of Open Access Journals (Sweden)

    Daniel J Catron

    2008-08-01

    Full Text Available Hybrid dysfunctions, such as sterility, may result in part from disruptions in the regulation of gene expression. Studies of hybrids within the Drosophila simulans clade have reported genes expressed above or below the expression observed in their parent species, and such misexpression is associated with male sterility in multigenerational backcross hybrids. However, these studies often examined whole bodies rather than testes or had limited replication using less-sensitive but global techniques. Here, we use a new RNA isolation technique to re-examine hybrid gene expression disruptions in both testes and whole bodies from single Drosophila males by real-time quantitative RT-PCR. We find two early-spermatogenesis transcripts are underexpressed in hybrid whole-bodies but not in assays of testes alone, while two late-spermatogenesis transcripts seem to be underexpressed in both whole-bodies and testes alone. Although the number of transcripts surveyed is limited, these results provide some support for a previous hypothesis that the spermatogenesis pathway in these sterile hybrids may be disrupted sometime after the expression of the early meiotic arrest genes.

  5. Endocrine Parameters and Phenotypes of the Growth Hormone Receptor Gene Disrupted (GHR−/−) Mouse

    Science.gov (United States)

    List, Edward O.; Sackmann-Sala, Lucila; Berryman, Darlene E.; Funk, Kevin; Kelder, Bruce; Gosney, Elahu S.; Okada, Shigeru; Ding, Juan; Cruz-Topete, Diana

    2011-01-01

    Disruption of the GH receptor (GHR) gene eliminates GH-induced intracellular signaling and, thus, its biological actions. Therefore, the GHR gene disrupted mouse (GHR−/−) has been and is a valuable tool for helping to define various parameters of GH physiology. Since its creation in 1995, this mouse strain has been used by our laboratory and others for numerous studies ranging from growth to aging. Some of the most notable discoveries are their extreme insulin sensitivity in the presence of obesity. Also, the animals have an extended lifespan, which has generated a large number of investigations into the roles of GH and IGF-I in the aging process. This review summarizes the many results derived from the GHR−/− mice. We have attempted to present the findings in the context of current knowledge regarding GH action and, where applicable, to discuss how these mice compare to GH insensitivity syndrome in humans. PMID:21123740

  6. Simultaneous Disruption of Mouse ASIC1a, ASIC2 and ASIC3 Genes Enhances Cutaneous Mechanosensitivity

    Science.gov (United States)

    Kang, Sinyoung; Jang, Jun Ho; Price, Margaret P.; Gautam, Mamta; Benson, Christopher J.; Gong, Huiyu; Welsh, Michael J.; Brennan, Timothy J.

    2012-01-01

    Three observations have suggested that acid-sensing ion channels (ASICs) might be mammalian cutaneous mechanoreceptors; they are structurally related to Caenorhabditis elegans mechanoreceptors, they are localized in specialized cutaneous mechanosensory structures, and mechanical displacement generates an ASIC-dependent depolarization in some neurons. However, previous studies of mice bearing a single disrupted ASIC gene showed only subtle or no alterations in cutaneous mechanosensitivity. Because functional redundancy of ASIC subunits might explain limited phenotypic alterations, we hypothesized that disrupting multiple ASIC genes would markedly impair cutaneous mechanosensation. We found the opposite. In behavioral studies, mice with simultaneous disruptions of ASIC1a, -2 and -3 genes (triple-knockouts, TKOs) showed increased paw withdrawal frequencies when mechanically stimulated with von Frey filaments. Moreover, in single-fiber nerve recordings of cutaneous afferents, mechanical stimulation generated enhanced activity in A-mechanonociceptors of ASIC TKOs compared to wild-type mice. Responses of all other fiber types did not differ between the two genotypes. These data indicate that ASIC subunits influence cutaneous mechanosensitivity. However, it is unlikely that ASICs directly transduce mechanical stimuli. We speculate that physical and/or functional association of ASICs with other components of the mechanosensory transduction apparatus contributes to normal cutaneous mechanosensation. PMID:22506072

  7. Functional evaluations of genes disrupted in patients with Tourette’s Disorder

    Directory of Open Access Journals (Sweden)

    Nawei eSun

    2016-02-01

    Full Text Available Tourette Disorder (TD is a highly heritable neurodevelopmental disorder with complex genetic architecture and unclear neuropathology. Disruptions of particular genes have been identified in subsets of TD patients. However, none of the findings has been replicated, probably due to the complex and heterogeneous genetic architecture of TD that involves both common and rare variants. To understand the etiology of TD, functional analyses are required to characterize the molecular and cellular consequences caused by mutations in candidate genes. Such molecular and cellular alterations may converge into common biological pathways underlying the heterogeneous genetic etiology of TD patients. Herein, we review specific genes implicated in TD etiology, discuss the functions of these genes in the mammalian central nervous system and the corresponding behavioral anomalies exhibited in animal models and, importantly, review functional analyses that can be performed to evaluate the role(s that the genetic disruptions might play in TD. Specifically, the functional assays include novel cell culture systems, genome editing techniques, bioinformatics approaches, transcriptomic analyses and genetically modified animal models applied or developed to study genes associated with TD or with other neurodevelopmental and neuropsychiatric disorders. By describing methods used to study diseases with genetic architecture similar to TD, we hope to develop a systematic framework for investigating the etiology of TD and related disorders.

  8. A high efficiency gene disruption strategy using a positive-negative split selection marker and electroporation for Fusarium oxysporum.

    Science.gov (United States)

    Liang, Liqin; Li, Jianqiang; Cheng, Lin; Ling, Jian; Luo, Zhongqin; Bai, Miao; Xie, Bingyan

    2014-11-01

    The Fusarium oxysporum species complex consists of fungal pathogens that cause serial vascular wilt disease on more than 100 cultivated species throughout the world. Gene function analysis is rapidly becoming more and more important as the whole-genome sequences of various F. oxysporum strains are being completed. Gene-disruption techniques are a common molecular tool for studying gene function, yet are often a limiting step in gene function identification. In this study we have developed a F. oxysporum high-efficiency gene-disruption strategy based on split-marker homologous recombination cassettes with dual selection and electroporation transformation. The method was efficiently used to delete three RNA-dependent RNA polymerase (RdRP) genes. The gene-disruption cassettes of three genes can be constructed simultaneously within a short time using this technique. The optimal condition for electroporation is 10μF capacitance, 300Ω resistance, 4kV/cm field strength, with 1μg of DNA (gene-disruption cassettes). Under these optimal conditions, we were able to obtain 95 transformants per μg DNA. And after positive-negative selection, the transformants were efficiently screened by PCR, screening efficiency averaged 85%: 90% (RdRP1), 85% (RdRP2) and 77% (RdRP3). This gene-disruption strategy should pave the way for high throughout genetic analysis in F. oxysporum. Copyright © 2014 Elsevier GmbH. All rights reserved.

  9. Efficient gene replacements in ku70 disruption strain of Aspergillus chevalieri var. intermedius

    Directory of Open Access Journals (Sweden)

    Qingqing Huang

    2017-01-01

    Full Text Available Aspergillus chevalieri var. intermedius is a dominant filamentous fungal species in Fuzhuan tea and is associated with the quality and health benefits of this tea. The sexual or asexual reproduction of this fungus depends on the osmotic pressure of the tea. Efforts to enhance the beneficial effects of A. chevalieri var. intermedius are hampered by difficulties in disrupting its genes. To address this issue, we identified the A. chevalieri var. intermedius homolog (Acku70 of human Ku70 and generated an Acku70 disruption strain (ΔAcku70, aiming to improve the gene replacement efficiency. ΔAcku70 grew at a slightly lower rate in vitro than the wild-type strain; however, the two strains exhibited similar sensitivity to temperature, osmotic pressure and the effects of ethyl methane sulphonate and H2O2. The replacement efficiency of veA and flbA dramatically increased in ΔAcku70 compared to that in the wild type. The efficiency of flbA replacement increased from 2.6% to 80%, whereas the frequency of veA disruption increased from 15.2% to 83.9% and from 30.8% to 86.8%. Thus, ΔAcku70 is suitable for use as a type strain for large-scale functional genomic analysis of A. chevalieri var. intermedius.

  10. Cre/lox-based multiple markerless gene disruption in the genome of the extreme thermophile Thermus thermophilus.

    Science.gov (United States)

    Togawa, Yoichiro; Nunoshiba, Tatsuo; Hiratsu, Keiichiro

    2018-02-01

    Markerless gene-disruption technology is particularly useful for effective genetic analyses of Thermus thermophilus (T. thermophilus), which have a limited number of selectable markers. In an attempt to develop a novel system for the markerless disruption of genes in T. thermophilus, we applied a Cre/lox system to construct a triple gene disruptant. To achieve this, we constructed two genetic tools, a loxP-htk-loxP cassette and cre-expressing plasmid, pSH-Cre, for gene disruption and removal of the selectable marker by Cre-mediated recombination. We found that the Cre/lox system was compatible with the proliferation of the T. thermophilus HB27 strain at the lowest growth temperature (50 °C), and thus succeeded in establishing a triple gene disruptant, the (∆TTC1454::loxP, ∆TTC1535KpnI::loxP, ∆TTC1576::loxP) strain, without leaving behind a selectable marker. During the process of the sequential disruption of multiple genes, we observed the undesired deletion and inversion of the chromosomal region between multiple loxP sites that were induced by Cre-mediated recombination. Therefore, we examined the effects of a lox66-htk-lox71 cassette by exploiting the mutant lox sites, lox66 and lox71, instead of native loxP sites. We successfully constructed a (∆TTC1535::lox72, ∆TTC1537::lox72) double gene disruptant without inducing the undesired deletion of the 0.7-kbp region between the two directly oriented lox72 sites created by the Cre-mediated recombination of the lox66-htk-lox71 cassette. This is the first demonstration of a Cre/lox system being applicable to extreme thermophiles in a genetic manipulation. Our results indicate that this system is a powerful tool for multiple markerless gene disruption in T. thermophilus.

  11. Gene inactivation in the plant pathogen Glomerella cingulata: three strategies for the disruption of the pectin lyase gene pnlA.

    Science.gov (United States)

    Bowen, J K; Templeton, M D; Sharrock, K R; Crowhurst, R N; Rikkerink, E H

    1995-01-20

    The feasibility of performing routine transformation-mediated mutagenesis in Glomerella cingulata was analysed by adopting three one-step gene disruption strategies targeted at the pectin lyase gene pnlA. The efficiencies of disruption following transformation with gene replacement- or gene truncation-disruption vectors were compared. To effect replacement-disruption, G. cingulata was transformed with a vector carrying DNA from the pnlA locus in which the majority of the coding sequence had been replaced by the gene for hygromycin B resistance. Two of the five transformants investigated contained an inactivated pnlA gene (pnlA-); both also contained ectopically integrated vector sequences. The efficacy of gene disruption by transformation with two gene truncation-disruption vectors was also assessed. Both vectors carried at 5' and 3' truncated copy of the pnlA coding sequence, adjacent to the gene for hygromycin B resistance. The promoter sequences controlling the selectable marker differed in the two vectors. In one vector the homologous G. cingulata gpdA promoter controlled hygromycin B phosphotransferase expression (homologous truncation vector), whereas in the second vector promoter elements were from the Aspergillus nidulans gpdA gene (heterologous truncation vector). Following transformation with the homologous truncation vector, nine transformants were analysed by Southern hybridisation; no transformants contained a disrupted pnlA gene. Of nineteen heterologous truncation vector transformants, three contained a disrupted pnlA gene; Southern analysis revealed single integrations of vector sequence at pnlA in two of these transformants. pnlA mRNA was not detected by Northern hybridisation in pnlA- transformants. pnlA- transformants failed to produce a PNLA protein with a pI identical to one normally detected in wild-type isolates by silver and activity staining of isoelectric focussing gels. Pathogenesis on Capsicum and apple was unaffected by disruption of

  12. EBV tegument protein BNRF1 disrupts DAXX-ATRX to activate viral early gene transcription.

    Directory of Open Access Journals (Sweden)

    Kevin Tsai

    2011-11-01

    Full Text Available Productive infection by herpesviruses involve the disabling of host-cell intrinsic defenses by viral encoded tegument proteins. Epstein-Barr Virus (EBV typically establishes a non-productive, latent infection and it remains unclear how it confronts the host-cell intrinsic defenses that restrict viral gene expression. Here, we show that the EBV major tegument protein BNRF1 targets host-cell intrinsic defense proteins and promotes viral early gene activation. Specifically, we demonstrate that BNRF1 interacts with the host nuclear protein Daxx at PML nuclear bodies (PML-NBs and disrupts the formation of the Daxx-ATRX chromatin remodeling complex. We mapped the Daxx interaction domain on BNRF1, and show that this domain is important for supporting EBV primary infection. Through reverse transcription PCR and infection assays, we show that BNRF1 supports viral gene expression upon early infection, and that this function is dependent on the Daxx-interaction domain. Lastly, we show that knockdown of Daxx and ATRX induces reactivation of EBV from latently infected lymphoblastoid cell lines (LCLs, suggesting that Daxx and ATRX play a role in the regulation of viral chromatin. Taken together, our data demonstrate an important role of BNRF1 in supporting EBV early infection by interacting with Daxx and ATRX; and suggest that tegument disruption of PML-NB-associated antiviral resistances is a universal requirement for herpesvirus infection in the nucleus.

  13. EBV Tegument Protein BNRF1 Disrupts DAXX-ATRX to Activate Viral Early Gene Transcription

    Science.gov (United States)

    Tsai, Kevin; Thikmyanova, Nadezhda; Wojcechowskyj, Jason A.; Delecluse, Henri-Jacques; Lieberman, Paul M.

    2011-01-01

    Productive infection by herpesviruses involve the disabling of host-cell intrinsic defenses by viral encoded tegument proteins. Epstein-Barr Virus (EBV) typically establishes a non-productive, latent infection and it remains unclear how it confronts the host-cell intrinsic defenses that restrict viral gene expression. Here, we show that the EBV major tegument protein BNRF1 targets host-cell intrinsic defense proteins and promotes viral early gene activation. Specifically, we demonstrate that BNRF1 interacts with the host nuclear protein Daxx at PML nuclear bodies (PML-NBs) and disrupts the formation of the Daxx-ATRX chromatin remodeling complex. We mapped the Daxx interaction domain on BNRF1, and show that this domain is important for supporting EBV primary infection. Through reverse transcription PCR and infection assays, we show that BNRF1 supports viral gene expression upon early infection, and that this function is dependent on the Daxx-interaction domain. Lastly, we show that knockdown of Daxx and ATRX induces reactivation of EBV from latently infected lymphoblastoid cell lines (LCLs), suggesting that Daxx and ATRX play a role in the regulation of viral chromatin. Taken together, our data demonstrate an important role of BNRF1 in supporting EBV early infection by interacting with Daxx and ATRX; and suggest that tegument disruption of PML-NB-associated antiviral resistances is a universal requirement for herpesvirus infection in the nucleus. PMID:22102817

  14. Targeted disruption of Ataxia-telangiectasia mutated gene in miniature pigs by somatic cell nuclear transfer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young June; Ahn, Kwang Sung; Kim, Minjeong; Kim, Min Ju; Park, Sang-Min; Ryu, Junghyun; Ahn, Jin Seop; Heo, Soon Young; Kang, Jee Hyun; Choi, You Jung [Department of Nanobiomedical Science and BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan (Korea, Republic of); Choi, Seong-Jun [Institute of Tissue Regeneration Engineering, Dankook University, Cheonan (Korea, Republic of); Shim, Hosup, E-mail: shim@dku.edu [Department of Nanobiomedical Science and BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan (Korea, Republic of); Institute of Tissue Regeneration Engineering, Dankook University, Cheonan (Korea, Republic of); Department of Physiology, Dankook University School of Medicine, Cheonan (Korea, Republic of)

    2014-10-03

    Highlights: • ATM gene-targeted pigs were produced by somatic cell nuclear transfer. • A novel large animal model for ataxia telangiectasia was developed. • The new model may provide an alternative to the mouse model. - Abstract: Ataxia telangiectasia (A-T) is a recessive autosomal disorder associated with pleiotropic phenotypes, including progressive cerebellar degeneration, gonad atrophy, and growth retardation. Even though A-T is known to be caused by the mutations in the Ataxia telangiectasia mutated (ATM) gene, the correlation between abnormal cellular physiology caused by ATM mutations and the multiple symptoms of A-T disease has not been clearly determined. None of the existing ATM mouse models properly reflects the extent to which neurological degeneration occurs in human. In an attempt to provide a large animal model for A-T, we produced gene-targeted pigs with mutations in the ATM gene by somatic cell nuclear transfer. The disrupted allele in the ATM gene of cloned piglets was confirmed via PCR and Southern blot analysis. The ATM gene-targeted pigs generated in the present study may provide an alternative to the current mouse model for the study of mechanisms underlying A-T disorder and for the development of new therapies.

  15. Targeted disruption of Ataxia-telangiectasia mutated gene in miniature pigs by somatic cell nuclear transfer

    International Nuclear Information System (INIS)

    Kim, Young June; Ahn, Kwang Sung; Kim, Minjeong; Kim, Min Ju; Park, Sang-Min; Ryu, Junghyun; Ahn, Jin Seop; Heo, Soon Young; Kang, Jee Hyun; Choi, You Jung; Choi, Seong-Jun; Shim, Hosup

    2014-01-01

    Highlights: • ATM gene-targeted pigs were produced by somatic cell nuclear transfer. • A novel large animal model for ataxia telangiectasia was developed. • The new model may provide an alternative to the mouse model. - Abstract: Ataxia telangiectasia (A-T) is a recessive autosomal disorder associated with pleiotropic phenotypes, including progressive cerebellar degeneration, gonad atrophy, and growth retardation. Even though A-T is known to be caused by the mutations in the Ataxia telangiectasia mutated (ATM) gene, the correlation between abnormal cellular physiology caused by ATM mutations and the multiple symptoms of A-T disease has not been clearly determined. None of the existing ATM mouse models properly reflects the extent to which neurological degeneration occurs in human. In an attempt to provide a large animal model for A-T, we produced gene-targeted pigs with mutations in the ATM gene by somatic cell nuclear transfer. The disrupted allele in the ATM gene of cloned piglets was confirmed via PCR and Southern blot analysis. The ATM gene-targeted pigs generated in the present study may provide an alternative to the current mouse model for the study of mechanisms underlying A-T disorder and for the development of new therapies

  16. GAP1, a novel selection and counter-selection marker for multiple gene disruptions in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Regenberg, Birgitte; Hansen, J.

    2000-01-01

    the GAP1 gene. This is caused by recombination between two Salmonella typuimurium hisG direct repeats embracing GAP1, and will result in a sub-population of gap1 cells. Such cells are selected on a medium containing D-histidine, and may subsequently be used for a second gene disruption. Hence, multiple...... flanked by short (60 bp) stretches of the gene in question. Through homologous recombination, the cassette will integrate into the target gene, which is thus replaced by GAP1, and mutants are selected for on minimal L-citrulline medium. When propagated under non-selective conditions, some cells will lose...... gene disruptions can be made fast, cheaply and easily in a gap1 strain, with two positive selection steps for each disruption. Copyright (C) 2000 John Wiley & Sons, Ltd....

  17. Association between variations in the disrupted in schizophrenia 1 gene and schizophrenia: A meta-analysis.

    Science.gov (United States)

    Xu, Yiliang; Ren, Jun; Ye, Haihong

    2018-04-20

    Schizophrenia is a severe psychiatric disorder. Genetic and functional studies have strongly implicated the disrupted in schizophrenia 1 gene (DISC1) as a candidate susceptibility gene for schizophrenia. Moreover, recent association studies have indicated that several DISC1 single nucleotide polymorphisms (SNPs) are associated with schizophrenia. However, the association is hardly replicate in different ethnic group. Here, we performed a meta-analysis of the association between DISC1 SNPs and schizophrenia in which the samples were divided into subgroups according to ethnicity. Both rs3738401 and rs821616 showed not significantly association with schizophrenia in the Caucasian, Asian, Japanese or Han Chinese populations. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Random insertion and gene disruption via transposon mutagenesis of Ureaplasma parvum using a mini-transposon plasmid.

    Science.gov (United States)

    Aboklaish, Ali F; Dordet-Frisoni, Emilie; Citti, Christine; Toleman, Mark A; Glass, John I; Spiller, O Brad

    2014-11-01

    While transposon mutagenesis has been successfully used for Mycoplasma spp. to disrupt and determine non-essential genes, previous attempts with Ureaplasma spp. have been unsuccessful. Using a polyethylene glycol-transformation enhancing protocol, we were able to transform three separate serovars of Ureaplasma parvum with a Tn4001-based mini-transposon plasmid containing a gentamicin resistance selection marker. Despite the large degree of homology between Ureaplasma parvum and Ureaplasma urealyticum, all attempts to transform the latter in parallel failed, with the exception of a single clinical U. urealyticum isolate. PCR probing and sequencing were used to confirm transposon insertion into the bacterial genome and identify disrupted genes. Transformation of prototype serovar 3 consistently resulted in transfer only of sequence between the mini-transposon inverted repeats, but some strains showed additional sequence transfer. Transposon insertion occurred randomly in the genome resulting in unique disruption of genes UU047, UU390, UU440, UU450, UU520, UU526, UU582 for single clones from a panel of screened clones. An intergenic insertion between genes UU187 and UU188 was also characterised. Two phenotypic alterations were observed in the mutated strains: Disruption of a DEAD-box RNA helicase (UU582) altered growth kinetics, while the U. urealyticum strain lost resistance to serum attack coincident with disruption of gene UUR10_137 and loss of expression of a 41 kDa protein. Transposon mutagenesis was used successfully to insert single copies of a mini-transposon into the genome and disrupt genes leading to phenotypic changes in Ureaplasma parvum strains. This method can now be used to deliver exogenous genes for expression and determine essential genes for Ureaplasma parvum replication in culture and experimental models. Copyright © 2014 Elsevier GmbH. All rights reserved.

  19. Maternal obesity disrupts circadian rhythms of clock and metabolic genes in the offspring heart and liver.

    Science.gov (United States)

    Wang, Danfeng; Chen, Siyu; Liu, Mei; Liu, Chang

    2015-06-01

    Early life nutritional adversity is tightly associated with the development of long-term metabolic disorders. Particularly, maternal obesity and high-fat diets cause high risk of obesity in the offspring. Those offspring are also prone to develop hyperinsulinemia, hepatic steatosis and cardiovascular diseases. However, the precise underlying mechanisms leading to these metabolic dysregulation in the offspring remain unclear. On the other hand, disruptions of diurnal circadian rhythms are known to impair metabolic homeostasis in various tissues including the heart and liver. Therefore, we investigated that whether maternal obesity perturbs the circadian expression rhythms of clock, metabolic and inflammatory genes in offspring heart and liver by using RT-qPCR and Western blotting analysis. Offspring from lean and obese dams were examined on postnatal day 17 and 35, when pups were nursed by their mothers or took food independently. On P17, genes examined in the heart either showed anti-phase oscillations (Cpt1b, Pparα, Per2) or had greater oscillation amplitudes (Bmal1, Tnf-α, Il-6). Such phase abnormalities of these genes were improved on P35, while defects in amplitudes still existed. In the liver of 17-day-old pups exposed to maternal obesity, the oscillation amplitudes of most rhythmic genes examined (except Bmal1) were strongly suppressed. On P35, the oscillations of circadian and inflammatory genes became more robust in the liver, while metabolic genes were still kept non-rhythmic. Maternal obesity also had a profound influence in the protein expression levels of examined genes in offspring heart and liver. Our observations indicate that the circadian clock undergoes nutritional programing, which may contribute to the alternations in energy metabolism associated with the development of metabolic disorders in early life and adulthood.

  20. Directed partial correlation: inferring large-scale gene regulatory network through induced topology disruptions.

    Directory of Open Access Journals (Sweden)

    Yinyin Yuan

    Full Text Available Inferring regulatory relationships among many genes based on their temporal variation in transcript abundance has been a popular research topic. Due to the nature of microarray experiments, classical tools for time series analysis lose power since the number of variables far exceeds the number of the samples. In this paper, we describe some of the existing multivariate inference techniques that are applicable to hundreds of variables and show the potential challenges for small-sample, large-scale data. We propose a directed partial correlation (DPC method as an efficient and effective solution to regulatory network inference using these data. Specifically for genomic data, the proposed method is designed to deal with large-scale datasets. It combines the efficiency of partial correlation for setting up network topology by testing conditional independence, and the concept of Granger causality to assess topology change with induced interruptions. The idea is that when a transcription factor is induced artificially within a gene network, the disruption of the network by the induction signifies a genes role in transcriptional regulation. The benchmarking results using GeneNetWeaver, the simulator for the DREAM challenges, provide strong evidence of the outstanding performance of the proposed DPC method. When applied to real biological data, the inferred starch metabolism network in Arabidopsis reveals many biologically meaningful network modules worthy of further investigation. These results collectively suggest DPC is a versatile tool for genomics research. The R package DPC is available for download (http://code.google.com/p/dpcnet/.

  1. Disruption of a cystine transporter downregulates expression of genes involved in sulfur regulation and cellular respiration

    Directory of Open Access Journals (Sweden)

    Jessica A. Simpkins

    2016-06-01

    Full Text Available Cystine and cysteine are important molecules for pathways such as redox signaling and regulation, and thus identifying cellular deficits upon deletion of the Saccharomyces cerevisiae cystine transporter Ers1p allows for a further understanding of cystine homeostasis. Previous complementation studies using the human ortholog suggest yeast Ers1p is a cystine transporter. Human CTNS encodes the protein Cystinosin, a cystine transporter that is embedded in the lysosomal membrane and facilitates the export of cystine from the lysosome. When CTNS is mutated, cystine transport is disrupted, leading to cystine accumulation, the diagnostic hallmark of the lysosomal storage disorder cystinosis. Here, we provide biochemical evidence for Ers1p-dependent cystine transport. However, the accumulation of intracellular cystine is not observed when the ERS1 gene is deleted from ers1-Δ yeast, supporting the existence of modifier genes that provide a mechanism in ers1-Δ yeast that prevents or corrects cystine accumulation. Upon comparison of the transcriptomes of isogenic ERS1+ and ers1-Δ strains of S. cerevisiae by DNA microarray followed by targeted qPCR, sixteen genes were identified as being differentially expressed between the two genotypes. Genes that encode proteins functioning in sulfur regulation, cellular respiration, and general transport were enriched in our screen, demonstrating pleiotropic effects of ers1-Δ. These results give insight into yeast cystine regulation and the multiple, seemingly distal, pathways that involve proper cystine recycling.

  2. Deletion of an X-inactivation boundary disrupts adjacent gene silencing.

    Directory of Open Access Journals (Sweden)

    Lindsay M Horvath

    2013-11-01

    Full Text Available In mammalian females, genes on one X are largely silenced by X-chromosome inactivation (XCI, although some "escape" XCI and are expressed from both Xs. Escapees can closely juxtapose X-inactivated genes and provide a tractable model for assessing boundary function at epigenetically regulated loci. To delimit sequences at an XCI boundary, we examined female mouse embryonic stem cells carrying X-linked BAC transgenes derived from an endogenous escape locus. Previously we determined that large BACs carrying escapee Kdm5c and flanking X-inactivated transcripts are properly regulated. Here we identify two lines with truncated BACs that partially and completely delete the distal Kdm5c XCI boundary. This boundary is not required for escape, since despite integrating into regions that are normally X inactivated, transgenic Kdm5c escapes XCI, as determined by RNA FISH and by structurally adopting an active conformation that facilitates long-range preferential association with other escapees. Yet, XCI regulation is disrupted in the transgene fully lacking the distal boundary; integration site genes up to 350 kb downstream of the transgene now inappropriately escape XCI. Altogether, these results reveal two genetically separable XCI regulatory activities at Kdm5c. XCI escape is driven by a dominant element(s retained in the shortest transgene that therefore lies within or upstream of the Kdm5c locus. Additionally, the distal XCI boundary normally plays an essential role in preventing nearby genes from escaping XCI.

  3. Cadmium-mediated disruption of cortisol biosynthesis involves suppression of corticosteroidogenic genes in rainbow trout

    International Nuclear Information System (INIS)

    Sandhu, Navdeep; Vijayan, Mathilakath M.

    2011-01-01

    Cadmium is widely distributed in the aquatic environment and is toxic to fish even at sublethal concentrations. This metal is an endocrine disruptor, and one well established role in teleosts is the suppression of adrenocorticotrophic hormone (ACTH)-stimulated cortisol biosynthesis by the interrenal tissue. However the mechanism(s) leading to this steroid suppression is poorly understood. We tested the hypothesis that cadmium targets genes encoding proteins critical for corticosteroid biosynthesis, including melanocortin 2 receptor (MC2R), steroidogenic acute regulatory protein (StAR) and cytochrome P450 side chain cleavage enzyme (P450scc), in rainbow trout (Oncorhynchus mykiss). To test this, head kidney slices (containing the interrenal tissues) were incubated in vitro with cadmium chloride (0, 10, 100 and 1000 nM) for 4 h either in the presence or absence of ACTH (0.5 IU/mL). In the unstimulated head kidney slices, cadmium exposure did not affect basal cortisol secretion and the mRNA levels of MC2R and P450scc, while StAR gene expression was significantly reduced. Cadmium exposure significantly suppressed ACTH-stimulated cortisol production in a dose-related fashion. This cadmium-mediated suppression in corticosteroidogenesis corresponded with a significant reduction in MC2R, StAR and P450scc mRNA levels in trout head kidney slices. The inhibition of ACTH-stimulated cortisol production and suppression of genes involved in corticosteroidogenesis by cadmium were completely abolished in the presence of 8-Bromo-cAMP (a cAMP analog). Overall, cadmium disrupts the expression of genes critical for corticosteroid biosynthesis in rainbow trout head kidney slices. However, the rescue of cortisol production as well as StAR and P450scc gene expressions by cAMP analog suggests that cadmium impact occurs upstream of cAMP production. We propose that MC2R signaling, the primary step in ACTH-induced cortocosteroidogenesis, is a key target for cadmium-mediated disruption of

  4. Cadmium-mediated disruption of cortisol biosynthesis involves suppression of corticosteroidogenic genes in rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Sandhu, Navdeep [Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada); Vijayan, Mathilakath M., E-mail: mvijayan@uwaterloo.ca [Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada)

    2011-05-15

    Cadmium is widely distributed in the aquatic environment and is toxic to fish even at sublethal concentrations. This metal is an endocrine disruptor, and one well established role in teleosts is the suppression of adrenocorticotrophic hormone (ACTH)-stimulated cortisol biosynthesis by the interrenal tissue. However the mechanism(s) leading to this steroid suppression is poorly understood. We tested the hypothesis that cadmium targets genes encoding proteins critical for corticosteroid biosynthesis, including melanocortin 2 receptor (MC2R), steroidogenic acute regulatory protein (StAR) and cytochrome P450 side chain cleavage enzyme (P450scc), in rainbow trout (Oncorhynchus mykiss). To test this, head kidney slices (containing the interrenal tissues) were incubated in vitro with cadmium chloride (0, 10, 100 and 1000 nM) for 4 h either in the presence or absence of ACTH (0.5 IU/mL). In the unstimulated head kidney slices, cadmium exposure did not affect basal cortisol secretion and the mRNA levels of MC2R and P450scc, while StAR gene expression was significantly reduced. Cadmium exposure significantly suppressed ACTH-stimulated cortisol production in a dose-related fashion. This cadmium-mediated suppression in corticosteroidogenesis corresponded with a significant reduction in MC2R, StAR and P450scc mRNA levels in trout head kidney slices. The inhibition of ACTH-stimulated cortisol production and suppression of genes involved in corticosteroidogenesis by cadmium were completely abolished in the presence of 8-Bromo-cAMP (a cAMP analog). Overall, cadmium disrupts the expression of genes critical for corticosteroid biosynthesis in rainbow trout head kidney slices. However, the rescue of cortisol production as well as StAR and P450scc gene expressions by cAMP analog suggests that cadmium impact occurs upstream of cAMP production. We propose that MC2R signaling, the primary step in ACTH-induced cortocosteroidogenesis, is a key target for cadmium-mediated disruption of

  5. Alteration of sheep coat color pattern by disruption of ASIP gene via CRISPR Cas9.

    Science.gov (United States)

    Zhang, Xuemei; Li, Wenrong; Liu, Chenxi; Peng, Xinrong; Lin, Jiapeng; He, Sangang; Li, Xuejiao; Han, Bing; Zhang, Ning; Wu, Yangsheng; Chen, Lei; Wang, Liqin; MaYila; Huang, Juncheng; Liu, Mingjun

    2017-08-15

    Coat color is an important characteristic and economic trait in domestic sheep. Aiming at alteration of Chinese merino sheep coat color by genome manipulation, we disrupted sheep agouti signaling protein gene by CRISPR/Cas9. A total of seven indels were identified in 5 of 6 born lambs. Each targeted lamb happened at least two kinds of modifications, and targeted lambs with multiple modifications displayed variety of coat color patterns. Three lambs with 4 bp deletion showed badgerface with black body coat color in two lambs, and brown coat color with light ventral pigmentation in another one. The black-white spotted color was observed in two lambs with 2 bp deletion. Further analysis unraveled that modifications happened in one or more than two copies of ASIP gene, and moreover, the additional spontaneous mutations of D 9 and/or D 5 preceding the targeting modification could also involve the formation of coat color patterns. Taken together, the entanglement of ASIP modifications by CRISPR/Cas9, spontaneous D 9 /D 5 mutations, and ASIP gene duplications contributed to the variety of coat color patterns in targeted lambs.

  6. Altering the selection capabilities of common cloning vectors via restriction enzyme mediated gene disruption

    Science.gov (United States)

    2013-01-01

    Background The cloning of gene sequences forms the basis for many molecular biological studies. One important step in the cloning process is the isolation of bacterial transformants carrying vector DNA. This involves a vector-encoded selectable marker gene, which in most cases, confers resistance to an antibiotic. However, there are a number of circumstances in which a different selectable marker is required or may be preferable. Such situations can include restrictions to host strain choice, two phase cloning experiments and mutagenesis experiments, issues that result in additional unnecessary cloning steps, in which the DNA needs to be subcloned into a vector with a suitable selectable marker. Results We have used restriction enzyme mediated gene disruption to modify the selectable marker gene of a given vector by cloning a different selectable marker gene into the original marker present in that vector. Cloning a new selectable marker into a pre-existing marker was found to change the selection phenotype conferred by that vector, which we were able to demonstrate using multiple commonly used vectors and multiple resistance markers. This methodology was also successfully applied not only to cloning vectors, but also to expression vectors while keeping the expression characteristics of the vector unaltered. Conclusions Changing the selectable marker of a given vector has a number of advantages and applications. This rapid and efficient method could be used for co-expression of recombinant proteins, optimisation of two phase cloning procedures, as well as multiple genetic manipulations within the same host strain without the need to remove a pre-existing selectable marker in a previously genetically modified strain. PMID:23497512

  7. Methylmercury-induced changes in gene transcription associated with neuroendocrine disruption in largemouth bass (Micropterus salmoides).

    Science.gov (United States)

    Richter, Catherine A; Martyniuk, Christopher J; Annis, Mandy L; Brumbaugh, William G; Chasar, Lia C; Denslow, Nancy D; Tillitt, Donald E

    2014-07-01

    Methyl-mercury (MeHg) is a potent neuroendocrine disruptor that impairs reproductive processes in fish. The objectives of this study were to (1) characterize transcriptomic changes induced by MeHg exposure in the female largemouth bass (LMB) hypothalamus under controlled laboratory conditions, (2) investigate the health and reproductive impacts of MeHg exposure on male and female largemouth bass (LMB) in the natural environment, and (3) identify MeHg-associated gene expression patterns in whole brain of female LMB from MeHg-contaminated habitats. The laboratory experiment was a single injection of 2.5 μg MeHg/g body weight for 96 h exposure. The field survey compared river systems in Florida, USA with comparably lower concentrations of MeHg (Wekiva, Santa Fe, and St. Johns Rivers) in fish and one river system with LMB that contained elevated concentrations of MeHg (St. Marys River). Microarray analysis was used to quantify transcriptomic responses to MeHg exposure. Although fish at the high-MeHg site did not show overt health or reproductive impairment, there were MeHg-responsive genes and pathways identified in the laboratory study that were also altered in fish from the high-MeHg site relative to fish at the low-MeHg sites. Gene network analysis suggested that MeHg regulated the expression targets of neuropeptide receptor and steroid signaling, as well as structural components of the cell. Disease-associated gene networks related to MeHg exposure, based upon expression data, included cerebellum ataxia, movement disorders, and hypercalcemia. Gene responses in the CNS are consistent with the documented neurotoxicological and neuroendocrine disrupting effects of MeHg in vertebrates. Published by Elsevier Inc.

  8. Methylmercury-induced changes in gene transcription associated with neuroendocrine disruption in largemouth bass (Micropterus salmoides)

    Science.gov (United States)

    Richter, Catherine A.; Martyniuk, Christopher J.; Annis, Mandy L.; Brumbaugh, William G.; Chasar, Lia C.; Denslow, Nancy D.; Tillitt, Donald E.

    2014-01-01

    Methyl-mercury (MeHg) is a potent neuroendocrine disruptor that impairs reproductive processes in fish. The objectives of this study were to (1) characterize transcriptomic changes induced by MeHg exposure in the female largemouth bass (LMB) hypothalamus under controlled laboratory conditions, (2) investigate the health and reproductive impacts of MeHg exposure on male and female largemouth bass (LMB) in the natural environment, and (3) identify MeHg-associated gene expression patterns in whole brain of female LMB from MeHg-contaminated habitats. The laboratory experiment was a single injection of 2.5 μg MeHg/g body weight for 96 h exposure. The field survey compared river systems in Florida, USA with comparably lower concentrations of MeHg (Wekiva, Santa Fe, and St. Johns Rivers) in fish and one river system with LMB that contained elevated concentrations of MeHg (St. Marys River). Microarray analysis was used to quantify transcriptomic responses to MeHg exposure. Although fish at the high-MeHg site did not show overt health or reproductive impairment, there were MeHg-responsive genes and pathways identified in the laboratory study that were also altered in fish from the high-MeHg site relative to fish at the low-MeHg sites. Gene network analysis suggested that MeHg regulated the expression targets of neuropeptide receptor and steroid signaling, as well as structural components of the cell. Disease-associated gene networks related to MeHg exposure, based upon expression data, included cerebellum ataxia, movement disorders, and hypercalcemia. Gene responses in the CNS are consistent with the documented neurotoxicological and neuroendocrine disrupting effects of MeHg in vertebrates.

  9. A potential disruptive technology in vaccine development: gene-based vaccines and their application to infectious diseases.

    Science.gov (United States)

    Kaslow, David C

    2004-10-01

    Vaccine development requires an amalgamation of disparate disciplines and has unique economic and regulatory drivers. Non-viral gene-based delivery systems, such as formulated plasmid DNA, are new and potentially disruptive technologies capable of providing 'cheaper, simpler, and more convenient-to-use' vaccines. Typically and somewhat ironically, disruptive technologies have poorer product performance, at least in the near-term, compared with the existing conventional technologies. Because successful product development requires that the product's performance must meet or exceed the efficacy threshold for a desired application, the appropriate selection of the initial product applications for a disruptive technology is critical for its successful evolution. In this regard, the near-term successes of gene-based vaccines will likely be for protection against bacterial toxins and acute viral and bacterial infections. Recent breakthroughs, however, herald increasing rather than languishing performance improvements in the efficacy of gene-based vaccines. Whether gene-based vaccines ultimately succeed in eliciting protective immunity in humans to persistent intracellular pathogens, such as HIV, malaria and tuberculosis, for which the conventional vaccine technologies have failed, remains to be determined. A success against any one of the persistent intracellular pathogens would be sufficient proof that gene-based vaccines represent a disruptive technology against which future vaccine technologies will be measured.

  10. Effects of disruption of heat shock genes on susceptibility of Escherichia coli to fluoroquinolones

    Directory of Open Access Journals (Sweden)

    Morioka Mizue

    2003-08-01

    Full Text Available Abstract Background It is well known that expression of certain bacterial genes responds rapidly to such stimuli as exposure to toxic chemicals and physical agents. It is generally believed that the proteins encoded in these genes are important for successful survival of the organism under the hostile conditions. Analogously, the proteins induced in bacterial cells exposed to antibiotics are believed to affect the organisms' susceptibility to these agents. Results We demonstrated that Escherichia coli cells exposed to levofloxacin (LVFX, a fluoroquinolone (FQ, induce the syntheses of heat shock proteins and RecA. To examine whether the heat shock proteins affect the bactericidal action of FQs, we constructed E. coli strains with mutations in various heat shock genes and tested their susceptibility to FQs. Mutations in dnaK, groEL, and lon increased this susceptibility; the lon mutant exhibited the greatest effects. The increased susceptibility of the lon mutant was corroborated by experiments in which the gene encoding the cell division inhibitor, SulA, was subsequently disrupted. SulA is induced by the SOS response and degraded by the Lon protease. The findings suggest that the hypersusceptibility of the lon mutant to FQs could be due to abnormally high levels of SulA protein resulting from the depletion of Lon and the continuous induction of the SOS response in the presence of FQs. Conclusion The present results show that the bactericidal action of FQs is moderately affected by the DnaK and GroEL chaperones and strongly affected by the Lon protease. FQs have contributed successfully to the treatment of various bacterial infections, but their widespread use and often misuse, coupled with emerging resistance, have gradually compromised their utility. Our results suggest that agents capable of inhibiting the Lon protease have potential for combination therapy with FQs.

  11. Disruption of a Plasmodium falciparum gene linked to male sexual development causes early arrest in gametocytogenesis.

    Science.gov (United States)

    Furuya, Tetsuya; Mu, Jianbing; Hayton, Karen; Liu, Anna; Duan, Junhui; Nkrumah, Louis; Joy, Deirdre A; Fidock, David A; Fujioka, Hisashi; Vaidya, Akhil B; Wellems, Thomas E; Su, Xin-zhuan

    2005-11-15

    A male gametocyte defect in the Plasmodium falciparum Dd2 parasite was previously discovered through the observation that all progeny clones in a Dd2 x HB3 genetic cross were the result of fertilization events between Dd2 female and HB3 male gametes. A determinant linked to the defect in Dd2 was subsequently mapped to an 800-kb segment on chromosome 12. Here, we report further mapping of the determinant to an 82-kb region and the identification of a candidate gene, P. falciparum male development gene 1 (pfmdv-1), that is expressed at a lower level in Dd2 compared with the wild-type normal male gametocyte-producing ancestor W2. Pfmdv-1 protein is sexual-stage specific and is located on the gametocyte plasma membrane, parasitophorous vacuole membrane, and the membranes of cleft-like structures within the erythrocyte. Disruption of pfmdv-1 results in a dramatic reduction in mature gametocytes, especially functional male gametocytes, with the majority of sexually committed parasites developmentally arrested at stage I. The pfmdv-1-knockout parasites show disturbed membrane structures, particularly multimembrane vesicles/tubes that likely derive from deformed cleft-like structures. Mosquito infectivity of the knockout parasites was also greatly reduced but not completely lost. The results suggest that pfmdv-1 plays a key role in gametocyte membrane formation and integrity.

  12. Gene Disruption Technologies Have the Potential to Transform Stored Product Insect Pest Control.

    Science.gov (United States)

    Perkin, Lindsey C; Adrianos, Sherry L; Oppert, Brenda

    2016-09-19

    Stored product insects feed on grains and processed commodities manufactured from grain post-harvest, reducing the nutritional value and contaminating food. Currently, the main defense against stored product insect pests is the pesticide fumigant phosphine. Phosphine is highly toxic to all animals, but is the most effective and economical control method, and thus is used extensively worldwide. However, many insect populations have become resistant to phosphine, in some cases to very high levels. New, environmentally benign and more effective control strategies are needed for stored product pests. RNA interference (RNAi) may overcome pesticide resistance by targeting the expression of genes that contribute to resistance in insects. Most data on RNAi in stored product insects is from the coleopteran genetic model, Tribolium castaneum, since it has a strong RNAi response via injection of double stranded RNA (dsRNA) in any life stage. Additionally, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology has been suggested as a potential resource for new pest control strategies. In this review we discuss background information on both gene disruption technologies and summarize the advances made in terms of molecular pest management in stored product insects, mainly T. castaneum, as well as complications and future needs.

  13. Gene Disruption Technologies Have the Potential to Transform Stored Product Insect Pest Control

    Directory of Open Access Journals (Sweden)

    Lindsey C. Perkin

    2016-09-01

    Full Text Available Stored product insects feed on grains and processed commodities manufactured from grain post-harvest, reducing the nutritional value and contaminating food. Currently, the main defense against stored product insect pests is the pesticide fumigant phosphine. Phosphine is highly toxic to all animals, but is the most effective and economical control method, and thus is used extensively worldwide. However, many insect populations have become resistant to phosphine, in some cases to very high levels. New, environmentally benign and more effective control strategies are needed for stored product pests. RNA interference (RNAi may overcome pesticide resistance by targeting the expression of genes that contribute to resistance in insects. Most data on RNAi in stored product insects is from the coleopteran genetic model, Tribolium castaneum, since it has a strong RNAi response via injection of double stranded RNA (dsRNA in any life stage. Additionally, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR technology has been suggested as a potential resource for new pest control strategies. In this review we discuss background information on both gene disruption technologies and summarize the advances made in terms of molecular pest management in stored product insects, mainly T. castaneum, as well as complications and future needs.

  14. Increased production of free fatty acids in Aspergillus oryzae by disruption of a predicted acyl-CoA synthetase gene.

    Science.gov (United States)

    Tamano, Koichi; Bruno, Kenneth S; Koike, Hideaki; Ishii, Tomoko; Miura, Ai; Umemura, Myco; Culley, David E; Baker, Scott E; Machida, Masayuki

    2015-04-01

    Fatty acids are attractive molecules as source materials for the production of biodiesel fuel. Previously, we attained a 2.4-fold increase in fatty acid production by increasing the expression of fatty acid synthesis-related genes in Aspergillus oryzae. In this study, we achieved an additional increase in the production of fatty acids by disrupting a predicted acyl-CoA synthetase gene in A. oryzae. The A. oryzae genome is predicted to encode six acyl-CoA synthetase genes and disruption of AO090011000642, one of the six genes, resulted in a 9.2-fold higher accumulation (corresponding to an increased production of 0.23 mmol/g dry cell weight) of intracellular fatty acid in comparison to the wild-type strain. Furthermore, by introducing a niaD marker from Aspergillus nidulans to the disruptant, as well as changing the concentration of nitrogen in the culture medium from 10 to 350 mM, fatty acid productivity reached 0.54 mmol/g dry cell weight. Analysis of the relative composition of the major intracellular free fatty acids caused by disruption of AO090011000642 in comparison to the wild-type strain showed an increase in stearic acid (7 to 26 %), decrease in linoleic acid (50 to 27 %), and no significant changes in palmitic or oleic acid (each around 20-25 %).

  15. Disruption of the APC gene by t(5;7) translocation in a Turcot family.

    Science.gov (United States)

    Sahnane, Nora; Bernasconi, Barbara; Carnevali, Ileana; Furlan, Daniela; Viel, Alessandra; Sessa, Fausto; Tibiletti, Maria Grazia

    2016-03-01

    Turcot syndrome (TS) refers to the combination of colorectal polyps and primary tumours of the central nervous system. TS is a heterogeneous genetic condition due to APC and/or mismatch repair germline mutations. When APC is involved the vast majority of mutations are truncating, but in approximately 20%-30% of patients with familial polyposis no germline mutation can be found. A 30-year-old Caucasian woman with a positive pedigree for TS was referred to our Genetic Counselling Service. She was negative for APC and MUTYH but showed a reciprocal balanced translocation t(5;7)(q22;p15) at chromosome analysis. FISH analysis using specific BAC probes demonstrated that 5q22 breakpoint disrupted the APC gene. Transcript analysis by MLPA and digital PCR revealed that the cytogenetic rearrangement involving the 3' end of the APC gene caused a defective expression of a truncated transcript. This result allowed cytogenetic analysis to be offered to all the other family members and segregation analysis clearly demonstrated that all the carriers were affected, whereas non-carriers did not have the polyposis. A cytogenetic approach permitted the identification of the mutation-causing disease in this family, and the segregation analysis together with the transcript study supported the pathogenetic role of this mutation. Karyotype analysis was used as a predictive test in all members of this family. This family suggests that clinically positive TS and FAP cases, which test negative with standard molecular analysis, could be easily and cost-effectively resolved by a classical and molecular cytogenetic approach. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. The bactericidal agent triclosan modulates thyroid hormone-associated gene expression and disrupts postembryonic anuran development

    International Nuclear Information System (INIS)

    Veldhoen, Nik; Skirrow, Rachel C.; Osachoff, Heather; Wigmore, Heidi; Clapson, David J.; Gunderson, Mark P.; Van Aggelen, Graham; Helbing, Caren C.

    2006-01-01

    We investigated whether exposure to environmentally relevant concentrations of the bactericidal agent, triclosan, induces changes in the thyroid hormone-mediated process of metamorphosis of the North American bullfrog, Rana catesbeiana and alters the expression profile of thyroid hormone receptor (TR) α and β, basic transcription element binding protein (BTEB) and proliferating nuclear cell antigen (PCNA) gene transcripts. Premetamorphic tadpoles were immersed in environmentally relevant concentrations of triclosan and injected with 1 x 10 -11 mol/g body weight 3,5,3'-triiodothyronine (T 3 ) or vehicle control. Morphometric measurements and steady-state mRNA levels obtained by quantitative polymerase chain reaction were determined. mRNA abundance was also examined in Xenopus laevis XTC-2 cells treated with triclosan and/or 10 nM T 3 . Tadpoles pretreated with triclosan concentrations as low as 0.15 ± 0.03 μg/L for 4 days showed increased hindlimb development and a decrease in total body weight following T 3 administration. Triclosan exposure also resulted in decreased T 3 -mediated TRβ mRNA expression in the tadpole tail fin and increased levels of PCNA transcript in the brain within 48 h of T 3 treatment whereas TRα and BTEB were unaffected. Triclosan alone altered thyroid hormone receptor α transcript levels in the brain of premetamorphic tadpoles and induced a transient weight loss. In XTC-2 cells, exposure to T 3 plus nominal concentrations of triclosan as low as 0.03 μg/L for 24 h resulted in altered thyroid hormone receptor mRNA expression. Exposure to low levels of triclosan disrupts thyroid hormone-associated gene expression and can alter the rate of thyroid hormone-mediated postembryonic anuran development

  17. The bactericidal agent triclosan modulates thyroid hormone-associated gene expression and disrupts postembryonic anuran development

    Energy Technology Data Exchange (ETDEWEB)

    Veldhoen, Nik [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada); Skirrow, Rachel C. [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Osachoff, Heather [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Wigmore, Heidi [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Clapson, David J. [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada); Gunderson, Mark P. [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada); Van Aggelen, Graham [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Helbing, Caren C. [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada)]. E-mail: chelbing@uvic.ca

    2006-12-01

    We investigated whether exposure to environmentally relevant concentrations of the bactericidal agent, triclosan, induces changes in the thyroid hormone-mediated process of metamorphosis of the North American bullfrog, Rana catesbeiana and alters the expression profile of thyroid hormone receptor (TR) {alpha} and {beta}, basic transcription element binding protein (BTEB) and proliferating nuclear cell antigen (PCNA) gene transcripts. Premetamorphic tadpoles were immersed in environmentally relevant concentrations of triclosan and injected with 1 x 10{sup -11} mol/g body weight 3,5,3'-triiodothyronine (T{sub 3}) or vehicle control. Morphometric measurements and steady-state mRNA levels obtained by quantitative polymerase chain reaction were determined. mRNA abundance was also examined in Xenopus laevis XTC-2 cells treated with triclosan and/or 10 nM T{sub 3}. Tadpoles pretreated with triclosan concentrations as low as 0.15 {+-} 0.03 {mu}g/L for 4 days showed increased hindlimb development and a decrease in total body weight following T{sub 3} administration. Triclosan exposure also resulted in decreased T{sub 3}-mediated TR{beta} mRNA expression in the tadpole tail fin and increased levels of PCNA transcript in the brain within 48 h of T{sub 3} treatment whereas TR{alpha} and BTEB were unaffected. Triclosan alone altered thyroid hormone receptor {alpha} transcript levels in the brain of premetamorphic tadpoles and induced a transient weight loss. In XTC-2 cells, exposure to T{sub 3} plus nominal concentrations of triclosan as low as 0.03 {mu}g/L for 24 h resulted in altered thyroid hormone receptor mRNA expression. Exposure to low levels of triclosan disrupts thyroid hormone-associated gene expression and can alter the rate of thyroid hormone-mediated postembryonic anuran development.

  18. Targeted Disruption of V600E-Mutant BRAF Gene by CRISPR-Cpf1

    Directory of Open Access Journals (Sweden)

    Meijia Yang

    2017-09-01

    Full Text Available BRAF-V600E (1799T > A is one of the most frequently reported driver mutations in multiple types of cancers, and patients with such mutations could benefit from selectively inactivating the mutant allele. Near this mutation site, there are two TTTN and one NGG protospacer-adjacent motifs (PAMs for Cpf1 and Cas9 CRISPR nucleases, respectively. The 1799T > A substitution also leads to the occurrence of a novel NGNG PAM for the EQR variant of Cas9. We examined the editing efficacy and selectivity of Cpf1, Cas9, and EQR variant to this mutation site. Only Cpf1 demonstrated robust activity to induce specific disruption of only mutant BRAF, not wild-type sequence. Cas9 recognized and cut both normal and mutant alleles, and no obvious gene editing events were observed using EQR variant. Our results support the potential applicability of Cpf1 in precision medicine through highly specific inactivation of many other gain-of-function mutations. Keywords: Cpf1, targeted therapy, BRAF V600E

  19. Discovering potential Streptomyces hormone producers by using disruptants of essential biosynthetic genes as indicator strains.

    Science.gov (United States)

    Thao, Nguyen B; Kitani, Shigeru; Nitta, Hiroko; Tomioka, Toshiya; Nihira, Takuya

    2017-10-01

    Autoregulators are low-molecular-weight signaling compounds that control the production of many secondary metabolites in actinomycetes and have been referred to as 'Streptomyces hormones'. Here, potential producers of Streptomyces hormones were investigated in 40 Streptomyces and 11 endophytic actinomycetes. Production of γ-butyrolactone-type (IM-2, VB) and butenolide-type (avenolide) Streptomyces hormones was screened using Streptomyces lavendulae FRI-5 (ΔfarX), Streptomyces virginiae (ΔbarX) and Streptomyces avermitilis (Δaco), respectively. In these strains, essential biosynthetic genes for Streptomyces hormones were disrupted, enabling them to respond solely to the externally added hormones. The results showed that 20% of each of the investigated strains produced IM-2 and VB, confirming that γ-butyrolactone-type Streptomyces hormones are the most common in actinomycetes. Unlike the γ-butyrolactone type, butenolide-type Streptomyces hormones have been discovered in recent years, but their distribution has been unclear. Our finding that 24% of actinomycetes (12 of 51 strains) showed avenolide activity revealed for the first time that the butenolide-type Streptomyces hormone is also common in actinomycetes.

  20. Disruption of the mouse Jhy gene causes abnormal ciliary microtubule patterning and juvenile hydrocephalus

    Science.gov (United States)

    Appelbe, Oliver K.; Bollman, Bryan; Attarwala, Ali; Triebes, Lindy A.; Muniz-Talavera, Hilmarie; Curry, Daniel J.; Schmidt, Jennifer V.

    2013-01-01

    SUMMARY Congenital hydrocephalus, the accumulation of excess cerebrospinal fluid (CSF) in the ventricles of the brain, affects one of every 1,000 children born today, making it one of the most common human developmental disorders. Genetic causes of hydrocephalus are poorly understood in humans, but animal models suggest a broad genetic program underlying the regulation of CSF balance. In this study, the random integration of a transgene into the mouse genome led to the development of an early onset and rapidly progressive hydrocephalus. Juvenile hydrocephalus transgenic mice (JhylacZ) inherit communicating hydrocephalus in an autosomal recessive fashion with dilation of the lateral ventricles observed as early as postnatal day 1.5. Ventricular dilation increases in severity over time, becoming fatal at 4-8 weeks of age. The ependymal cilia lining the lateral ventricles are morphologically abnormal and reduced in number in JhylacZ/lacZ brains, and ultrastructural analysis revealed disorganization of the expected 9+2 microtubule pattern. Rather, the majority of JhylacZ/lacZ cilia develop axonemes with 9+0 or 8+2 microtubule structures. Disruption of an unstudied gene, 4931429I11Rik (now named Jhy) appears to underlie the hydrocephalus of JhylacZ/lacZ mice, and the Jhy transcript and protein are decreased in JhylacZ/lacZ mice. Partial phenotypic rescue was achieved in JhylacZ/lacZ mice by the introduction of a bacterial artificial chromosome (BAC) carrying 60-70% of the JHY protein coding sequence. Jhy is evolutionarily conserved from humans to basal vertebrates, but the predicted JHY protein lacks identifiable functional domains. Ongoing studies are directed at uncovering the physiological function of JHY and its role in CSF homeostasis. PMID:23906841

  1. Bacterial niche-specific genome expansion is coupled with highly frequent gene disruptions in deep-sea sediments

    KAUST Repository

    Wang, Yong; Yang, Jiang Ke; Lee, On On; Li, Tie Gang; Al-Suwailem, Abdulaziz M.; Danchin, Antoine; Qian, Pei-Yuan

    2011-01-01

    The complexity and dynamics of microbial metagenomes may be evaluated by genome size, gene duplication and the disruption rate between lineages. In this study, we pyrosequenced the metagenomes of microbes obtained from the brine and sediment of a deep-sea brine pool in the Red Sea to explore the possible genomic adaptations of the microbes in response to environmental changes. The microbes from the brine and sediments (both surface and deep layers) of the Atlantis II Deep brine pool had similar communities whereas the effective genome size varied from 7.4 Mb in the brine to more than 9 Mb in the sediment. This genome expansion in the sediment samples was due to gene duplication as evidenced by enrichment of the homologs. The duplicated genes were highly disrupted, on average by 47.6% and 70% for the surface and deep layers of the Atlantis II Deep sediment samples, respectively. The disruptive effects appeared to be mainly due to point mutations and frameshifts. In contrast, the homologs from the Atlantis II Deep brine sample were highly conserved and they maintained relatively small copy numbers. Likely, the adaptation of the microbes in the sediments was coupled with pseudogenizations and possibly functional diversifications of the paralogs in the expanded genomes. The maintenance of the pseudogenes in the large genomes is discussed. © 2011 Wang et al.

  2. Paired D10A Cas9 nickases are sometimes more efficient than individual nucleases for gene disruption.

    Science.gov (United States)

    Gopalappa, Ramu; Suresh, Bharathi; Ramakrishna, Suresh; Kim, Hyongbum Henry

    2018-03-23

    The use of paired Cas9 nickases instead of Cas9 nuclease drastically reduces off-target effects. Because both nickases must function for a nickase pair to make a double-strand break, the efficiency of paired nickases can intuitively be expected to be lower than that of either corresponding nuclease alone. Here, we carefully compared the gene-disrupting efficiency of Cas9 paired nickases with that of nucleases. Interestingly, the T7E1 assay and deep sequencing showed that on-target efficiency of paired D10A Cas9 nickases was frequently comparable, but sometimes higher than that of either corresponding nucleases in mammalian cells. As the underlying mechanism, we found that the HNH domain, which is preserved in the D10A Cas9 nickase, has higher activity than the RuvC domain in mammalian cells. In this study, we showed: (i) the in vivo cleavage efficiency of the HNH domain of Cas9 in mammalian cells is higher than that of the RuvC domain, (ii) paired Cas9 nickases are sometimes more efficient than individual nucleases for gene disruption. We envision that our findings which were overlooked in previous reports will serve as a new potential guideline for tool selection for CRISPR-Cas9-mediated gene disruption, facilitating efficient and precise genome editing.

  3. Bacterial niche-specific genome expansion is coupled with highly frequent gene disruptions in deep-sea sediments

    KAUST Repository

    Wang, Yong

    2011-12-21

    The complexity and dynamics of microbial metagenomes may be evaluated by genome size, gene duplication and the disruption rate between lineages. In this study, we pyrosequenced the metagenomes of microbes obtained from the brine and sediment of a deep-sea brine pool in the Red Sea to explore the possible genomic adaptations of the microbes in response to environmental changes. The microbes from the brine and sediments (both surface and deep layers) of the Atlantis II Deep brine pool had similar communities whereas the effective genome size varied from 7.4 Mb in the brine to more than 9 Mb in the sediment. This genome expansion in the sediment samples was due to gene duplication as evidenced by enrichment of the homologs. The duplicated genes were highly disrupted, on average by 47.6% and 70% for the surface and deep layers of the Atlantis II Deep sediment samples, respectively. The disruptive effects appeared to be mainly due to point mutations and frameshifts. In contrast, the homologs from the Atlantis II Deep brine sample were highly conserved and they maintained relatively small copy numbers. Likely, the adaptation of the microbes in the sediments was coupled with pseudogenizations and possibly functional diversifications of the paralogs in the expanded genomes. The maintenance of the pseudogenes in the large genomes is discussed. © 2011 Wang et al.

  4. Bacterial niche-specific genome expansion is coupled with highly frequent gene disruptions in deep-sea sediments.

    Directory of Open Access Journals (Sweden)

    Yong Wang

    Full Text Available The complexity and dynamics of microbial metagenomes may be evaluated by genome size, gene duplication and the disruption rate between lineages. In this study, we pyrosequenced the metagenomes of microbes obtained from the brine and sediment of a deep-sea brine pool in the Red Sea to explore the possible genomic adaptations of the microbes in response to environmental changes. The microbes from the brine and sediments (both surface and deep layers of the Atlantis II Deep brine pool had similar communities whereas the effective genome size varied from 7.4 Mb in the brine to more than 9 Mb in the sediment. This genome expansion in the sediment samples was due to gene duplication as evidenced by enrichment of the homologs. The duplicated genes were highly disrupted, on average by 47.6% and 70% for the surface and deep layers of the Atlantis II Deep sediment samples, respectively. The disruptive effects appeared to be mainly due to point mutations and frameshifts. In contrast, the homologs from the Atlantis II Deep brine sample were highly conserved and they maintained relatively small copy numbers. Likely, the adaptation of the microbes in the sediments was coupled with pseudogenizations and possibly functional diversifications of the paralogs in the expanded genomes. The maintenance of the pseudogenes in the large genomes is discussed.

  5. Cultured human peripheral blood mononuclear cells alter their gene expression when challenged with endocrine-disrupting chemicals

    International Nuclear Information System (INIS)

    Wens, B.; De Boever, P.; Verbeke, M.; Hollanders, K.; Schoeters, G.

    2013-01-01

    Endocrine disrupting chemicals (EDCs) have the potential to interfere with the hormonal system and may negatively influence human health. Microarray analysis was used in this study to investigate differential gene expression in human peripheral blood cells (PBMCs) after in vitro exposure to EDCs. PBMCs, isolated from blood samples of four male and four female healthy individuals, were exposed in vitro for 18 h to either a dioxin-like polychlorinated biphenyl (PCB126, 1 μM), a non-dioxin-like polychlorinated biphenyl (PCB153, 10 μM), a brominated flame retardant (BDE47, 10 μM), a perfluorinated alkyl acid (PFOA, 10 μM) or bisphenol (BPA, 10 μM). ANOVA analysis revealed a significant change in the expression of 862 genes as a result of EDC exposure. The gender of the donors did not affect gene expression. Hierarchical cluster analysis created three groups and clustered: (1) PCB126-exposed samples, (2) PCB153 and BDE47, (3) PFOA and BPA. The number of differentially expressed genes varied per compound and ranged from 60 to 192 when using fold change and multiplicity corrected p-value as filtering criteria. Exposure to PCB126 induced the AhR signaling pathway. BDE47 and PCB153 are known to disrupt thyroid metabolism and exposure influenced the expression of the nuclear receptors PPARγ and ESR2, respectively. BPA and PFOA did not induce significant changes in the expression of known nuclear receptors. Overall, each compound produced a unique gene expression signature affecting pathways and GO processes linked to metabolism and inflammation. Twenty-nine genes were significantly altered in expression under all experimental conditions. Six of these genes (HSD11B2, MMP11, ADIPOQ, CEL, DUSP9 and TUB) could be associated with obesity and metabolic syndrome. In conclusion, microarray analysis identified that PBMCs altered their gene expression response in vitro when challenged with EDCs. Our screening approach has identified a number of gene candidates that warrant

  6. Postnatal Cardiac Gene Editing Using CRISPR/Cas9 With AAV9-Mediated Delivery of Short Guide RNAs Results in Mosaic Gene Disruption.

    Science.gov (United States)

    Johansen, Anne Katrine; Molenaar, Bas; Versteeg, Danielle; Leitoguinho, Ana Rita; Demkes, Charlotte; Spanjaard, Bastiaan; de Ruiter, Hesther; Akbari Moqadam, Farhad; Kooijman, Lieneke; Zentilin, Lorena; Giacca, Mauro; van Rooij, Eva

    2017-10-27

    CRISPR/Cas9 (clustered regularly interspaced palindromic repeats/CRISPR-associated protein 9)-based DNA editing has rapidly evolved as an attractive tool to modify the genome. Although CRISPR/Cas9 has been extensively used to manipulate the germline in zygotes, its application in postnatal gene editing remains incompletely characterized. To evaluate the feasibility of CRISPR/Cas9-based cardiac genome editing in vivo in postnatal mice. We generated cardiomyocyte-specific Cas9 mice and demonstrated that Cas9 expression does not affect cardiac function or gene expression. As a proof-of-concept, we delivered short guide RNAs targeting 3 genes critical for cardiac physiology, Myh6 , Sav1 , and Tbx20 , using a cardiotropic adeno-associated viral vector 9. Despite a similar degree of DNA disruption and subsequent mRNA downregulation, only disruption of Myh6 was sufficient to induce a cardiac phenotype, irrespective of short guide RNA exposure or the level of Cas9 expression. DNA sequencing analysis revealed target-dependent mutations that were highly reproducible across mice resulting in differential rates of in- and out-of-frame mutations. Finally, we applied a dual short guide RNA approach to effectively delete an important coding region of Sav1 , which increased the editing efficiency. Our results indicate that the effect of postnatal CRISPR/Cas9-based cardiac gene editing using adeno-associated virus serotype 9 to deliver a single short guide RNA is target dependent. We demonstrate a mosaic pattern of gene disruption, which hinders the application of the technology to study gene function. Further studies are required to expand the versatility of CRISPR/Cas9 as a robust tool to study novel cardiac gene functions in vivo. © 2017 American Heart Association, Inc.

  7. Disruption of var2csa gene impairs placental malaria associated adhesion phenotype.

    Directory of Open Access Journals (Sweden)

    Nicola K Viebig

    Full Text Available Infection with Plasmodium falciparum during pregnancy is one of the major causes of malaria related morbidity and mortality in newborn and mothers. The complications of pregnancy-associated malaria result mainly from massive adhesion of Plasmodium falciparum-infected erythrocytes (IE to chondroitin sulfate A (CSA present in the placental intervillous blood spaces. Var2CSA, a member of the P. falciparum erythrocyte membrane protein 1 (PfEMP1 family is the predominant parasite ligand mediating CSA binding. However, experimental evidence suggests that other host receptors, such as hyaluronic acid (HA and the neonatal Fc receptor, may also support placental binding. Here we used parasites in which var2csa was genetically disrupted to evaluate the contribution of these receptors to placental sequestration and to identify additional adhesion receptors that may be involved in pregnancy-associated malaria. By comparison to the wild-type parasites, the FCR3delta var2csa mutants could not be selected for HA adhesion, indicating that var2csa is not only essential for IE cytoadhesion to the placental receptor CSA, but also to HA. However, further studies using different pure sources of HA revealed that the previously observed binding results from CSA contamination in the bovine vitreous humor HA preparation. To identify CSA-independent placental interactions, FCR3delta var2csa mutant parasites were selected for adhesion to the human placental trophoblastic BeWo cell line. BeWo selected parasites revealed a multi-phenotypic adhesion population expressing multiple var genes. However, these parasites did not cytoadhere specifically to the syncytiotrophoblast lining of placental cryosections and were not recognized by sera from malaria-exposed women in a parity dependent manner, indicating that the surface molecules present on the surface of the BeWo selected population are not specifically expressed during the course of pregnancy-associated malaria. Taken

  8. Targeted Gene Disruption of the Cyclo (L-Phe, L-Pro Biosynthetic Pathway in Streptomyces sp. US24 Strain

    Directory of Open Access Journals (Sweden)

    Samiha Sioud

    2007-01-01

    Full Text Available We have previously isolated a new actinomycete strain from Tunisian soil called Streptomyces sp. US24, and have shown that it produces two bioactive molecules including a Cyclo (L-Phe, L-Pro diketopiperazine (DKP. To identify the structural genes responsible for the synthesis of this DKP derivative, a PCR amplification (696 bp was carried out using the Streptomyces sp. US24 genomic DNA as template and two degenerate oligonucleotides designed by analogy with genes encoding peptide synthetases (NRPS. The detection of DKP derivative biosynthetic pathway of the Streptomyces sp. US24 strain was then achieved by gene disruption via homologous recombination using a suicide vector derived from the conjugative plasmid pSET152 and containing the PCR product. Chromatography analysis, biological tests and spectroscopic studies of supernatant cultures of the wild-type Streptomyces sp. US24 strain and three mutants obtained by this gene targeting disruption approach showed that the amplified DNA fragment is required for Cyclo (L-Phe, L-Pro biosynthesis in Streptomyces sp. US24 strain. This DKP derivative seems to be produced either directly via a nonribosomal pathway or as a side product in the course of nonribosomal synthesis of a longer peptide.

  9. Highly efficient DNA-free gene disruption in the agricultural pest Ceratitis capitata by CRISPR-Cas9 ribonucleoprotein complexes.

    Science.gov (United States)

    Meccariello, Angela; Monti, Simona Maria; Romanelli, Alessandra; Colonna, Rita; Primo, Pasquale; Inghilterra, Maria Grazia; Del Corsano, Giuseppe; Ramaglia, Antonio; Iazzetti, Giovanni; Chiarore, Antonia; Patti, Francesco; Heinze, Svenia D; Salvemini, Marco; Lindsay, Helen; Chiavacci, Elena; Burger, Alexa; Robinson, Mark D; Mosimann, Christian; Bopp, Daniel; Saccone, Giuseppe

    2017-08-30

    The Mediterranean fruitfly Ceratitis capitata (medfly) is an invasive agricultural pest of high economic impact and has become an emerging model for developing new genetic control strategies as an alternative to insecticides. Here, we report the successful adaptation of CRISPR-Cas9-based gene disruption in the medfly by injecting in vitro pre-assembled, solubilized Cas9 ribonucleoprotein complexes (RNPs) loaded with gene-specific single guide RNAs (sgRNA) into early embryos. When targeting the eye pigmentation gene white eye (we), a high rate of somatic mosaicism in surviving G0 adults was observed. Germline transmission rate of mutated we alleles by G0 animals was on average above 52%, with individual cases achieving nearly 100%. We further recovered large deletions in the we gene when two sites were simultaneously targeted by two sgRNAs. CRISPR-Cas9 targeting of the Ceratitis ortholog of the Drosophila segmentation paired gene (Ccprd) caused segmental malformations in late embryos and in hatched larvae. Mutant phenotypes correlate with repair by non-homologous end-joining (NHEJ) lesions in the two targeted genes. This simple and highly effective Cas9 RNP-based gene editing to introduce mutations in C. capitata will significantly advance the design and development of new effective strategies for pest control management.

  10. Further enhanced production of heterologous proteins by double-gene disruption (ΔAosedD ΔAovps10) in a hyper-producing mutant of Aspergillus oryzae.

    Science.gov (United States)

    Zhu, Lin; Maruyama, Jun-ichi; Kitamoto, Katsuhiko

    2013-07-01

    The filamentous fungus Aspergillus oryzae is used as one of the most favored hosts for heterologous protein production due to its ability to secrete large amounts of proteins into the culture medium. We previously generated a hyper-producing mutant strain of A. oryzae, AUT1, which produced 3.2- and 2.6-fold higher levels of bovine chymosin (CHY) and human lysozyme (HLY), respectively, compared with the wild-type strain. However, further enhancement of heterologous protein production by multiple gene disruption is difficult because of the low gene-targeting efficiency in strain AUT1. Here, we disrupted the ligD gene, which is involved in nonhomologous recombination, and the pyrG gene to create uridine/uracil auxotrophy in strain AUT1, to generate a hyper-producing mutant applicable to pyrG marker recycling with highly efficient gene targeting. We generated single and double disruptants of the tripeptidyl peptidase gene AosedD and vacuolar sorting receptor gene Aovps10 in the hyper-producing mutant background, and found that all disruptants showed significant increases in heterologous protein production. Particularly, double disruption of the Aovps10 and AosedD genes increased the production levels of CHY and HLY by 1.6- and 2.1-fold, respectively, compared with the parental strain. Thus, we successfully generated a fungal host for further enhancing the heterologous protein production ability by combining mutational and molecular breeding techniques.

  11. Gene disruption of Plasmodium falciparum p52 results in attenuation of malaria liver stage development in cultured primary human hepatocytes.

    Directory of Open Access Journals (Sweden)

    Ben C L van Schaijk

    Full Text Available Difficulties with inducing sterile and long lasting protective immunity against malaria with subunit vaccines has renewed interest in vaccinations with attenuated Plasmodium parasites. Immunizations with sporozoites that are attenuated by radiation (RAS can induce strong protective immunity both in humans and rodent models of malaria. Recently, in rodent parasites it has been shown that through the deletion of a single gene, sporozoites can also become attenuated in liver stage development and, importantly, immunization with these sporozoites results in immune responses identical to RAS. The promise of vaccination using these genetically attenuated sporozoites (GAS depends on translating the results in rodent malaria models to human malaria. In this study, we perform the first essential step in this transition by disrupting, p52, in P. falciparum an ortholog of the rodent parasite gene, p36p, which we had previously shown can confer long lasting protective immunity in mice. These P. falciparum P52 deficient sporozoites demonstrate gliding motility, cell traversal and an invasion rate into primary human hepatocytes in vitro that is comparable to wild type sporozoites. However, inside the host hepatocyte development is arrested very soon after invasion. This study reveals, for the first time, that disrupting the equivalent gene in both P. falciparum and rodent malaria Plasmodium species generates parasites that become similarly arrested during liver stage development and these results pave the way for further development of GAS for human use.

  12. Disruption of Msx-1 and Msx-2 reveals roles for these genes in craniofacial, eye, and axial development.

    Science.gov (United States)

    Foerst-Potts, L; Sadler, T W

    1997-05-01

    In mouse embryos, the muscle segment homeobox genes, Msx-1 and Msx-2 are expressed during critical stages of neural tube, neural crest, and craniofacial development, suggesting that these genes play important roles in organogenesis and cell differentiation. Although the patterns of expression are intriguing, little is known about the function of these genes in vertebrate embryonic development. Therefore, the expression of both genes, separately and together, was disrupted using antisense oligodeoxynucleotides and whole embryo culture techniques. Antisense attenuation of Msx-1 during early stages of neurulation produced hypoplasia of the maxillary, mandibular, and frontonasal prominences, eye anomalies, and somite and neural tube abnormalities. Eye defects consisted of enlarged optic vesicles, which may ultimately result in micropthalmia similar to that observed in Small eye mice homozygous for mutations in the Pax-6 gene. Histological sections and SEM analysis revealed a thinning of the neuroepithelium in the diencephalon and optic vesicle and mesenchymal deficiencies in the craniofacial region. Injections of Msx-2 antisense oligodeoxynucleotides produced similar malformations as those targeting Msx-1, with the exception that there was an increase in number and severity of neural tube and somite defects. Embryos injected with the combination of Msx-1 + Msx-2 antisense oligodeoxynucleotides showed no novel abnormalities, suggesting that the genes do not operate in a redundant manner.

  13. Beware of memes in the interpretation of your results - lessons from gene-disrupted mice in fertilization research.

    Science.gov (United States)

    Okabe, Masaru

    2018-05-22

    For decades, researchers in the fertilization field reported various candidate factors involved in sperm-egg interaction through experiments using enzyme inhibitors and/or antibodies. However, almost all of these factors have been shown to be nonessential by gene disruption experiments. Recently, attention has focused on the low reproducibility of papers in many research fields. In this Review, I retrospectively revisit how fertilization factors were misinterpreted and led to wrong hypotheses in relation to the reportedly low reproducibility of scientific papers. © 2018 Federation of European Biochemical Societies.

  14. Improved heterologous protein production by a tripeptidyl peptidase gene (AosedD) disruptant of the filamentous fungus Aspergillus oryzae.

    Science.gov (United States)

    Zhu, Lin; Nemoto, Takeshi; Yoon, Jaewoo; Maruyama, Jun-ichi; Kitamoto, Katsuhiko

    2012-01-01

    Proteolytic degradation is one of the serious bottlenecks limiting the yields of heterologous protein production by Aspergillus oryzae. In this study, we selected a tripeptidyl peptidase gene AosedD (AO090166000084) as a candidate potentially degrading the heterologous protein, and performed localization analysis of the fusion protein AoSedD-EGFP in A. oryzae. As a result, the AoSedD-EGFP was observed in the septa and cell walls as well as in the culture medium, suggesting that AoSedD is a secretory enzyme. An AosedD disruptant was constructed to investigate an effect of AoSedD on the production level of heterologous proteins and protease activity. Both of the total protease and tripeptidyl peptidase activities in the culture medium of the AosedD disruptant were decreased as compared to those of the control strain. The maximum yields of recombinant bovine chymosin (CHY) and human lysozyme (HLY) produced by the AosedD disruptants showed approximately 2.9- and 1.7-fold increases, respectively, as compared to their control strains. These results suggest that AoSedD is one of the major proteases involved in the proteolytic degradation of recombinant proteins in A. oryzae.

  15. Molecular breeding of the Mureka-non-forming sake koji mold from Aspergillus oryzae by the disruption of the mreA gene.

    Science.gov (United States)

    Kubodera, Takafumi; Yamashita, Nobuo; Nishimura, Akira

    2003-01-01

    Mureka-non-forming sake koji molds were constructed from an Aspergillus oryzae industrial strain by the disruption of the mreA gene using a host-vector system with the ptrA gene as a dominant selectable marker. All of the mreA gene disruptants obtained retained the advantages of the host strain in terms of the brewing characteristics, while their isoamyl alcohol oxidase (IAAOD) activities were significantly lower than that of the host strain. Sake brewing was successfully carried out using the koji prepared with the disruptants, followed by storage of the resultant non-pasteurized sake (nama-shu). The isovaleraldehyde (i-Val) concentration in the sake brewed the host strain increased rapidly and reached the threshold values for mureka, 1.8 ppm and 2.6 ppm after storage at 20 degrees C for 42 d and 63 d, respectively, while those of the disruptants were less than 0.5 ppm even after storage at 20 degrees C or 30 degrees C for 63 d. In the sensory evaluation of the sake stored at 20 degrees C or 30 degrees C for 63 d, all members of the panel recognized the strong mureka flavor of the sake brewed with the host strain, while they did not detect this flavor in the sake brewed with the disruptants. Thus, we concluded that the mreA gene disruptants can be used for the production of sake in which mureka is not formed.

  16. Evidence of cardiac involvement in the fetal inflammatory response syndrome: disruption of gene networks programming cardiac development in nonhuman primates.

    Science.gov (United States)

    Mitchell, Timothy; MacDonald, James W; Srinouanpranchanh, Sengkeo; Bammler, Theodor K; Merillat, Sean; Boldenow, Erica; Coleman, Michelle; Agnew, Kathy; Baldessari, Audrey; Stencel-Baerenwald, Jennifer E; Tisoncik-Go, Jennifer; Green, Richard R; Gale, Michael J; Rajagopal, Lakshmi; Adams Waldorf, Kristina M

    2018-04-01

    Most early preterm births are associated with intraamniotic infection and inflammation, which can lead to systemic inflammation in the fetus. The fetal inflammatory response syndrome describes elevations in the fetal interleukin-6 level, which is a marker for inflammation and fetal organ injury. An understanding of the effects of inflammation on fetal cardiac development may lead to insight into the fetal origins of adult cardiovascular disease. The purpose of this study was to determine whether the fetal inflammatory response syndrome is associated with disruptions in gene networks that program fetal cardiac development. We obtained fetal cardiac tissue after necropsy from a well-described pregnant nonhuman primate model (pigtail macaque, Macaca nemestrina) of intrauterine infection (n=5) and controls (n=5). Cases with the fetal inflammatory response syndrome (fetal plasma interleukin-6 >11 pg/mL) were induced by either choriodecidual inoculation of a hypervirulent group B streptococcus strain (n=4) or intraamniotic inoculation of Escherichia coli (n=1). RNA and protein were extracted from fetal hearts and profiled by microarray and Luminex (Millipore, Billerica, MA) for cytokine analysis, respectively. Results were validated by quantitative reverse transcriptase polymerase chain reaction. Statistical and bioinformatics analyses included single gene analysis, gene set analysis, Ingenuity Pathway Analysis (Qiagen, Valencia, CA), and Wilcoxon rank sum. Severe fetal inflammation developed in the context of intraamniotic infection and a disseminated bacterial infection in the fetus. Interleukin-6 and -8 in fetal cardiac tissues were elevated significantly in fetal inflammatory response syndrome cases vs controls (P1.5-fold change, P<.05) in the fetal heart (analysis of variance). Altered expression of select genes was validated by quantitative reverse transcriptase polymerase chain reaction that included several with known functions in cardiac injury, morphogenesis

  17. Conditions for gene disruption by homologous recombination of exogenous DNA into the Sulfolobus solfataricus genome

    NARCIS (Netherlands)

    Albers, Sonja-Verena; Driessen, Arnold J.M.

    2008-01-01

    The construction of directed gene deletion mutants is an essential tool in molecular biology that allows functional studies on the role of genes in their natural environment. For hyperthermophilic archaea, it has been difficult to obtain a reliable system to construct such mutants. However, during

  18. Conditions for gene disruption by homologous recombination of exogenous DNA into the Sulfolobus solfataricus genome

    OpenAIRE

    Albers, Sonja-Verena; Driessen, Arnold J. M.

    2008-01-01

    The construction of directed gene deletion mutants is an essential tool in molecular biology that allows functional studies on the role of genes in their natural environment. For hyperthermophilic archaea, it has been difficult to obtain a reliable system to construct such mutants. However, during the past years, systems have been developed for Thermococcus kodakarensis and two Sulfolobus species, S. ac...

  19. Estrogenic Endocrine Disrupting Chemicals Influencing NRF1 Regulated Gene Networks in the Development of Complex Human Brain Diseases.

    Science.gov (United States)

    Preciados, Mark; Yoo, Changwon; Roy, Deodutta

    2016-12-13

    During the development of an individual from a single cell to prenatal stages to adolescence to adulthood and through the complete life span, humans are exposed to countless environmental and stochastic factors, including estrogenic endocrine disrupting chemicals. Brain cells and neural circuits are likely to be influenced by estrogenic endocrine disruptors (EEDs) because they strongly dependent on estrogens. In this review, we discuss both environmental, epidemiological, and experimental evidence on brain health with exposure to oral contraceptives, hormonal therapy, and EEDs such as bisphenol-A (BPA), polychlorinated biphenyls (PCBs), phthalates, and metalloestrogens, such as, arsenic, cadmium, and manganese. Also we discuss the brain health effects associated from exposure to EEDs including the promotion of neurodegeneration, protection against neurodegeneration, and involvement in various neurological deficits; changes in rearing behavior, locomotion, anxiety, learning difficulties, memory issues, and neuronal abnormalities. The effects of EEDs on the brain are varied during the entire life span and far-reaching with many different mechanisms. To understand endocrine disrupting chemicals mechanisms, we use bioinformatics, molecular, and epidemiologic approaches. Through those approaches, we learn how the effects of EEDs on the brain go beyond known mechanism to disrupt the circulatory and neural estrogen function and estrogen-mediated signaling. Effects on EEDs-modified estrogen and nuclear respiratory factor 1 (NRF1) signaling genes with exposure to natural estrogen, pharmacological estrogen-ethinyl estradiol, PCBs, phthalates, BPA, and metalloestrogens are presented here. Bioinformatics analysis of gene-EEDs interactions and brain disease associations identified hundreds of genes that were altered by exposure to estrogen, phthalate, PCBs, BPA or metalloestrogens. Many genes modified by EEDs are common targets of both 17 β-estradiol (E2) and NRF1. Some of

  20. Gene disruptions indicate an essential function for the LmmCRK1 cdc2-related kinase of Leishmania mexicana.

    Science.gov (United States)

    Mottram, J C; McCready, B P; Brown, K G; Grant, K M

    1996-11-01

    The generation of homozygous null mutants for the crk1 Cdc2-Related Kinase of Leishmania mexicana was attempted using targeted gene disruption. Promastigote mutants heterozygous for crk1 were readily isolated with a hyg-targeting fragment, but attempts to create null mutants by second-round transfections with a bie-targeting fragment yielded two classes of mutant, neither of which was null. First, the transfected fragment formed an episome; second, the cloned transfectants were found to contain wild-type crk1 alleles as well as hyg and ble integrations. DNA-content analysis revealed that these mutants were triploid or tetraploid. Plasticity in chromosome number following targeting has been proposed as a means by which Leishmania avoids deletion of essential genes. These data support this theory and implicate crk1 as an essential gene, validating CRK1 as a potential drug target. L mexicana transfected with a Trypanosoma brucel homologue, tbcrk1, was shown to be viable in an immcrk1 null background, thus showing complementation of function between these trypanosomatid genes. The expression of crk1 was further manipulated by engineering a six-histidine tag at the C-terminus of the kinase, allowing purification of the active complex by affinity selection on Nl(2+)-nitriloacetic acid (NTA) agarose.

  1. Disruption of polyubiquitin gene Ubc leads to defective proliferation of hepatocytes and bipotent fetal liver epithelial progenitor cells

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyejin; Yoon, Min-Sik; Ryu, Kwon-Yul, E-mail: kyryu@uos.ac.kr

    2013-06-07

    Highlights: •Proliferation capacity of Ubc{sup −/−} FLCs was reduced during culture in vitro. •Ubc is required for proliferation of both hepatocytes and bipotent FLEPCs. •Bipotent FLEPCs exhibit highest Ubc transcription and proliferation capacity. •Cell types responsible for Ubc{sup −/−} fetal liver developmental defect were identified. -- Abstract: We have previously demonstrated that disruption of polyubiquitin gene Ubc leads to mid-gestation embryonic lethality most likely due to a defect in fetal liver development, which can be partially rescued by ectopic expression of Ub. In a previous study, we assessed the cause of embryonic lethality with respect to the fetal liver hematopoietic system. We confirmed that Ubc{sup −/−} embryonic lethality could not be attributed to impaired function of hematopoietic stem cells, which raises the question of whether or not FLECs such as hepatocytes and bile duct cells, the most abundant cell types in the liver, are affected by disruption of Ubc and contribute to embryonic lethality. To answer this, we isolated FLCs from E13.5 embryos and cultured them in vitro. We found that proliferation capacity of Ubc{sup −/−} cells was significantly reduced compared to that of control cells, especially during the early culture period, however we did not observe the increased number of apoptotic cells. Furthermore, levels of Ub conjugate, but not free Ub, decreased upon disruption of Ubc expression in FLCs, and this could not be compensated for by upregulation of other poly- or mono-ubiquitin genes. Intriguingly, the highest Ubc expression levels throughout the entire culture period were observed in bipotent FLEPCs. Hepatocytes and bipotent FLEPCs were most affected by disruption of Ubc, resulting in defective proliferation as well as reduced cell numbers in vitro. These results suggest that defective proliferation of these cell types may contribute to severe reduction of fetal liver size and potentially mid

  2. Essential gene disruptions reveal complex relationships between phenotypic robustness, pleiotropy, and fitness

    Science.gov (United States)

    Bauer, Christopher R; Li, Shuang; Siegal, Mark L

    2015-01-01

    The concept of robustness in biology has gained much attention recently, but a mechanistic understanding of how genetic networks regulate phenotypic variation has remained elusive. One approach to understand the genetic architecture of variability has been to analyze dispensable gene deletions in model organisms; however, the most important genes cannot be deleted. Here, we have utilized two systems in yeast whereby essential genes have been altered to reduce expression. Using high-throughput microscopy and image analysis, we have characterized a large number of morphological phenotypes, and their associated variation, for the majority of essential genes in yeast. Our results indicate that phenotypic robustness is more highly dependent upon the expression of essential genes than on the presence of dispensable genes. Morphological robustness appears to be a general property of a genotype that is closely related to pleiotropy. While the fitness profile across a range of expression levels is idiosyncratic to each gene, the global pattern indicates that there is a window in which phenotypic variation can be released before fitness effects are observable. PMID:25609648

  3. Conditions for gene disruption by homologous recombination of exogenous DNA into the Sulfolobus solfataricus genome

    Directory of Open Access Journals (Sweden)

    Sonja-Verena Albers

    2008-01-01

    Full Text Available The construction of directed gene deletion mutants is an essential tool in molecular biology that allows functional studies on the role of genes in their natural environment. For hyperthermophilic archaea, it has been difficult to obtain a reliable system to construct such mutants. However, during the past years, systems have been developed for Thermococcus kodakarensis and two Sulfolobus species, S. acidocaldarius and derivatives of S. solfataricus 98/2. Here we describe an optimization of the method for integration of exogenous DNA into S. solfataricus PBL 2025, an S. solfataricus 98/2 derivative, based on lactose auxotrophy that now allows for routine gene inactivation.

  4. Conditions for gene disruption by homologous recombination of exogenous DNA into the Sulfolobus solfataricus genome.

    Science.gov (United States)

    Albers, Sonja-Verena; Driessen, Arnold J M

    2008-12-01

    The construction of directed gene deletion mutants is an essential tool in molecular biology that allows functional studies on the role of genes in their natural environment. For hyperthermophilic archaea, it has been difficult to obtain a reliable system to construct such mutants. However, during the past years, systems have been developed for Thermococcus kodakarensis and two Sulfolobus species, S. acidocaldarius and derivatives of S. solfataricus 98/2. Here we describe an optimization of the method for integration of exogenous DNA into S. solfataricus PBL 2025, an S. solfataricus 98/2 derivative, based on lactose auxotrophy that now allows for routine gene inactivation.

  5. Estrogenic Endocrine Disrupting Chemicals Influencing NRF1 Regulated Gene Networks in the Development of Complex Human Brain Diseases

    Directory of Open Access Journals (Sweden)

    Mark Preciados

    2016-12-01

    Full Text Available During the development of an individual from a single cell to prenatal stages to adolescence to adulthood and through the complete life span, humans are exposed to countless environmental and stochastic factors, including estrogenic endocrine disrupting chemicals. Brain cells and neural circuits are likely to be influenced by estrogenic endocrine disruptors (EEDs because they strongly dependent on estrogens. In this review, we discuss both environmental, epidemiological, and experimental evidence on brain health with exposure to oral contraceptives, hormonal therapy, and EEDs such as bisphenol-A (BPA, polychlorinated biphenyls (PCBs, phthalates, and metalloestrogens, such as, arsenic, cadmium, and manganese. Also we discuss the brain health effects associated from exposure to EEDs including the promotion of neurodegeneration, protection against neurodegeneration, and involvement in various neurological deficits; changes in rearing behavior, locomotion, anxiety, learning difficulties, memory issues, and neuronal abnormalities. The effects of EEDs on the brain are varied during the entire life span and far-reaching with many different mechanisms. To understand endocrine disrupting chemicals mechanisms, we use bioinformatics, molecular, and epidemiologic approaches. Through those approaches, we learn how the effects of EEDs on the brain go beyond known mechanism to disrupt the circulatory and neural estrogen function and estrogen-mediated signaling. Effects on EEDs-modified estrogen and nuclear respiratory factor 1 (NRF1 signaling genes with exposure to natural estrogen, pharmacological estrogen-ethinyl estradiol, PCBs, phthalates, BPA, and metalloestrogens are presented here. Bioinformatics analysis of gene-EEDs interactions and brain disease associations identified hundreds of genes that were altered by exposure to estrogen, phthalate, PCBs, BPA or metalloestrogens. Many genes modified by EEDs are common targets of both 17 β-estradiol (E2 and

  6. A mammalian model for Laron syndrome produced by targeted disruption of the mouse growth hormone receptor/binding protein gene (the Laron mouse)

    OpenAIRE

    Zhou, Yihua; Xu, Bixiong C.; Maheshwari, Hiralal G.; He, Li; Reed, Michael; Lozykowski, Maria; Okada, Shigeru; Cataldo, Lori; Coschigamo, Karen; Wagner, Thomas E.; Baumann, Gerhard; Kopchick, John J.

    1997-01-01

    Laron syndrome [growth hormone (GH) insensitivity syndrome] is a hereditary dwarfism resulting from defects in the GH receptor (GHR) gene. GHR deficiency has not been reported in mammals other than humans. Many aspects of GHR dysfunction remain unknown because of ethical and practical limitations in studying humans. To create a mammalian model for this disease, we generated mice bearing a disrupted GHR/binding protein (GHR/BP) gene through a homologous gene targeting approach. Homozygous GHR/...

  7. Disruption of the 37-kDa/67-kDa laminin receptor gene in bovine ...

    African Journals Online (AJOL)

    ... gene encoding for the prion binding site in bovine fetal fibroblasts. The heterozygous BFF are ready to be used in producing homozygous cattle, which will be applied to study the interaction between prion and the 37-kDa/67-kDa LRP/LR. Key words: Prion, PrPC, PrPSc, 37-kDa/67-kDa laminin receptor, gene targeting.

  8. Disruption of the Candida albicans TPS1 Gene Encoding Trehalose-6-Phosphate Synthase Impairs Formation of Hyphae and Decreases Infectivity†

    Science.gov (United States)

    Zaragoza, Oscar; Blazquez, Miguel A.; Gancedo, Carlos

    1998-01-01

    The TPS1 gene from Candida albicans, which encodes trehalose-6-phosphate synthase, has been cloned by functional complementation of a tps1 mutant from Saccharomyces cerevisiae. In contrast with the wild-type strain, the double tps1/tps1 disruptant did not accumulate trehalose at stationary phase or after heat shock. Growth of the tps1/tps1 disruptant at 30°C was indistinguishable from that of the wild type. However, at 42°C it did not grow on glucose or fructose but grew normally on galactose or glycerol. At 37°C, the yeast-hypha transition in the mutant in glucose-calf serum medium did not occur. During growth at 42°C, the mutant did not form hyphae in galactose or in glycerol. Some of the growth defects observed may be traced to an unbalanced sugar metabolism that reduces the cellular content of ATP. Mice inoculated with 106 CFU of the tps1/tps1 mutant did not show visible symptoms of infection 16 days after inoculation, while those similarly inoculated with wild-type cells were dead 12 days after inoculation. PMID:9683476

  9. Endocrine disruptive effects of chemicals eluted from nitrile-butadiene rubber gloves using reporter gene assay systems.

    Science.gov (United States)

    Satoh, Kanako; Nonaka, Ryouichi; Ohyama, Ken-ichi; Nagai, Fumiko; Ogata, Akio; Iida, Mitsuru

    2008-03-01

    Disposable gloves made of nitrile-butadiene rubber (NBR) are used for contact with foodstuffs rather than polyvinyl chloride gloves containing di(2-ethylhexyl)phthalate (DEHP), because endocrine-disruptive effects are suspected for phthalate diesters including DEHP. However, 4,4'-butylidenebis(6-t-butyl-m-cresol) (BBBC), 2,4-di-t-butylphenol, and 2,2,4-trimetyl-1,3-pentanediol diisobutyrate can be eluted from NBR gloves, and possibly also detected in food. In this study, we examined the endocrine-disrupting effects of these chemicals via androgen receptor (AR) and estrogen receptor (ER)-mediated pathways using stably transfected reporter gene cell lines expressing AR (AR-EcoScreen system) and ER (MVLN cells), respectively. We also examined the binding activities of these chemicals to AR and ER. The IC50 value of BBBC for antagonistic androgen was in the range of 10(-6)M. The strength of inhibition was about 5 times that of a known androgen antagonist, 1,1'-(2,2-dichloroethylidene)bis[4-chlorobenzene] (p,p'-DDE), and similar to that of bisphenol A. The IC50 value of BBBC for antagonistic estrogen was in the range of 10(-6)M. These results suggest that BBBC and its structural homologue, 4,4'-thiobis(6-t-butyl-m-cresol) are androgen and estrogen antagonists. It is therefore necessary to study these chemicals in vivo, and clarify their effect on the endocrine system.

  10. EAAC1 Gene Deletion Increases Neuronal Death and Blood Brain Barrier Disruption after Transient Cerebral Ischemia in Female Mice

    Directory of Open Access Journals (Sweden)

    Bo Young Choi

    2014-10-01

    Full Text Available EAAC1 is important in modulating brain ischemic tolerance. Mice lacking EAAC1 exhibit increased susceptibility to neuronal oxidative stress in mice after transient cerebral ischemia. EAAC1 was first described as a glutamate transporter but later recognized to also function as a cysteine transporter in neurons. EAAC1-mediated transport of cysteine into neurons contributes to neuronal antioxidant function by providing cysteine substrates for glutathione synthesis. Here we evaluated the effects of EAAC1 gene deletion on hippocampal blood vessel disorganization after transient cerebral ischemia. EAAC1−/− female mice subjected to transient cerebral ischemia by common carotid artery occlusion for 30 min exhibited twice as much hippocampal neuronal death compared to wild-type female mice as well as increased reduction of neuronal glutathione, blood–brain barrier (BBB disruption and vessel disorganization. Pre-treatment of N-acetyl cysteine, a membrane-permeant cysteine prodrug, increased basal glutathione levels in the EAAC1−/− female mice and reduced ischemic neuronal death, BBB disruption and vessel disorganization. These findings suggest that cysteine uptake by EAAC1 is important for neuronal antioxidant function under ischemic conditions.

  11. Formation of Highly Twisted Ribbons in a Carboxymethylcellulase Gene-Disrupted Strain of a Cellulose-Producing Bacterium

    Science.gov (United States)

    Sugano, Yasushi; Shoda, Makoto; Sakakibara, Hitoshi; Oiwa, Kazuhiro; Tuzi, Satoru; Imai, Tomoya; Sugiyama, Junji; Takeuchi, Miyuki; Yamauchi, Daisuke

    2013-01-01

    Cellulases are enzymes that normally digest cellulose; however, some are known to play essential roles in cellulose biosynthesis. Although some endogenous cellulases of plants and cellulose-producing bacteria are reportedly involved in cellulose production, their functions in cellulose production are unknown. In this study, we demonstrated that disruption of the cellulase (carboxymethylcellulase) gene causes irregular packing of de novo-synthesized fibrils in Gluconacetobacter xylinus, a cellulose-producing bacterium. Cellulose production was remarkably reduced and small amounts of particulate material were accumulated in the culture of a cmcax-disrupted G. xylinus strain (F2-2). The particulate material was shown to contain cellulose by both solid-state 13C nuclear magnetic resonance analysis and Fourier transform infrared spectroscopy analysis. Electron microscopy revealed that the cellulose fibrils produced by the F2-2 cells were highly twisted compared with those produced by control cells. This hypertwisting of the fibrils may reduce cellulose synthesis in the F2-2 strains. PMID:23243308

  12. Genetic disruption of the KLF1 gene to overexpress the γ-globin gene using the CRISPR/Cas9 system.

    Science.gov (United States)

    Shariati, Laleh; Khanahmad, Hossein; Salehi, Mansoor; Hejazi, Zahra; Rahimmanesh, Ilnaz; Tabatabaiefar, Mohammad Amin; Modarressi, Mohammad Hossein

    2016-10-01

    β-thalassemia comprises a major group of human genetic disorders involving a decrease in or an end to the normal synthesis of the β-globin chains of hemoglobin. KLF1 is a key regulatory molecule involved in the γ- to β-globin gene switching process directly inducing the expression of the β-globin gene and indirectly repressing γ-globin. The present study aimed to investigate the ability of an engineered CRISPR/Cas9 system with respect to disrupting the KLF1 gene to inhibit the γ- to β-hemoglobin switching process in K562 cells. We targeted three sites on the KLF1 gene, two of which are upstream of codon 288 in exon 2 and the other site being in exon 3. The average indel percentage in the cells transfected with CRISPR a, b and c was approximately 24%. Relative quantification was performed for the assessment of γ-globin expression. The levels of γ-globin mRNA on day 5 of differentiation were 8.1-, 7.7- and 1.8-fold in the cells treated with CRISPR/Cas9 a, b and c, respectively,compared to untreated cells. The measurement of HbF expression levels confirmed the same results. The findings obtained in the present study support the induction of an indel mutation in the KLF1 gene leading to a null allele. As a result, the effect of KLF1 on the expression of BCL11A is decreased and its inhibitory effect on γ-globin gene expression is removed. Application of CRISPR technology to induce an indel in the KLF1 gene in adult erythroid progenitors may provide a method for activating fetal hemoglobin expression in individuals with β-thalassemia or sickle cell disease. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Short-term exposure of arsenite disrupted thyroid endocrine system and altered gene transcription in the HPT axis in zebrafish.

    Science.gov (United States)

    Sun, Hong-Jie; Li, Hong-Bo; Xiang, Ping; Zhang, Xiaowei; Ma, Lena Q

    2015-10-01

    Arsenic (As) pollution in aquatic environment may adversely impact fish health by disrupting their thyroid hormone homeostasis. In this study, we explored the effect of short-term exposure of arsenite (AsIII) on thyroid endocrine system in zebrafish. We measured As concentrations, As speciation, and thyroid hormone thyroxine levels in whole zebrafish, oxidative stress (H2O2) and damage (MDA) in the liver, and gene transcription in hypothalamic-pituitary-thyroid (HPT) axis in the brain and liver tissues of zebrafish after exposing to different AsIII concentrations for 48 h. Result indicated that exposure to AsIII increased inorganic As in zebrafish to 0.46-0.72 mg kg(-1), induced oxidative stress with H2O2 being increased by 1.4-2.5 times and caused oxidative damage with MDA being augmented by 1.6 times. AsIII exposure increased thyroxine levels by 1.3-1.4 times and modulated gene transcription in HPT axis. Our study showed AsIII caused oxidative damage, affected thyroid endocrine system and altered gene transcription in HPT axis in zebrafish. Published by Elsevier Ltd.

  14. Immunocytochemistry and fluorescence imaging efficiently identify individual neurons with CRISPR/Cas9-mediated gene disruption in primary cortical cultures.

    Science.gov (United States)

    Tsunematsu, Hiroto; Uyeda, Akiko; Yamamoto, Nobuhiko; Sugo, Noriyuki

    2017-08-01

    CRISPR/Cas9 system is a powerful method to investigate the role of genes by introducing a mutation selectively and efficiently to specific genome positions in cell and animal lines. However, in primary neuron cultures, this method is affected by the issue that the effectiveness of CRISPR/Cas9 is different in each neuron. Here, we report an easy, quick and reliable method to identify mutants induced by the CRISPR/Cas9 system at a single neuron level, using immunocytochemistry (ICC) and fluorescence imaging. Dissociated cortical cells were transfected with CRISPR/Cas9 plasmids targeting the transcription factor cAMP-response element binding protein (CREB). Fluorescence ICC with CREB antibody and quantitative analysis of fluorescence intensity demonstrated that CREB expression disappeared in a fraction of the transfected neurons. The downstream FOS expression was also decreased in accordance with suppressed CREB expression. Moreover, dendritic arborization was decreased in the transfected neurons which lacked CREB immunoreactivity. Detection of protein expression is efficient to identify individual postmitotic neurons with CRISPR/Cas9-mediated gene disruption in primary cortical cultures. The present method composed of CRISPR/Cas9 system, ICC and fluorescence imaging is applicable to study the function of various genes at a single-neuron level.

  15. Targeted disruption of the Hexa gene results in mice with biochemical and pathologic features of Tay-Sachs disease

    Energy Technology Data Exchange (ETDEWEB)

    Proia, R.L.; Yamanaka, S.; Johnson, M.D. [and others

    1994-09-01

    Tay-Sachs disease, the prototype of the G{sub M2} gangliosidoses, is a catastrophic neurodegenerative disorder of infancy. The disease is caused by mutations in the HEXA gene resulting in an absence of the lysosomal enzyme, {beta}-hexosaminidase A. As consequence of the enzyme deficiency, G{sub M2} ganglioside accumulates progressively, beginning early in fetal life, to excessive amounts in the central nervous system (CNS). Rapid mental and motor deterioration starting in the first year of life leads to death by 2 to 4 years of age. Through the targeted disruption of the Hexa gene in embryonic stem cells, we have produced mice with biochemical and neuropathologic features of Tay-Sachs disease. The mutant mice exhibited less than 1% of normal {beta}-hexosaminidase A activity and accumulated G{sub M2} ganglioside in their CNS in an age-dependent manner. The accumulated ganglioside was stored in neurons as membranous cytoplasmic bodies characteristically found in the neurons of Tay-Sachs disease patients. At three to five months of age the mutant mice showed no apparent defects in motor or memory function. These {beta}-hexosaminidase A deficient mice should be useful for devising strategies to introduce functional enzymes and genes into the CNS. This model may also be valuable for studying the biochemical and pathologic changes occurring during the course of the disease.

  16. Enhancement of carotenoid production by disrupting the C22-sterol desaturase gene (CYP61 in Xanthophyllomyces dendrorhous

    Directory of Open Access Journals (Sweden)

    Loto Iris

    2012-10-01

    Full Text Available Abstract Background Xanthophyllomyces dendrorhous is a basidiomycetous yeast that synthesizes astaxanthin, which is a carotenoid with a great biotechnological impact. The ergosterol and carotenoid synthesis pathways are derived from the mevalonate pathway, and in both pathways, cytochrome P450 enzymes are involved. Results In this study, we isolated and described the X. dendrorhous CYP61 gene, which encodes a cytochrome P450 involved in ergosterol biosynthesis. This gene is composed of nine exons and encodes a 526 amino acid polypeptide that shares significant percentages of identity and similitude with the C22-sterol desaturase, CYP61, from other fungi. Mutants derived from different parental strains were obtained by disrupting the CYP61 gene with an antibiotic selection marker. These mutants were not able to produce ergosterol and accumulated ergosta-5,8,22-trien-3-ol and ergosta-5,8-dien-3-ol. Interestingly, all of the mutants had a more intense red color phenotype than their respective parental strains. The carotenoid composition was qualitatively and quantitatively analyzed by RP-HPLC, revealing that the carotenoid content was higher in the mutant strains without major changes in their composition. The expression of the HMGR gene, which encodes an enzyme involved in the mevalonate pathway (3-hydroxy-3-methylglutaryl-CoA reductase, was analyzed by RT-qPCR showing that its transcript levels are higher in the CYP61 mutants. Conclusions These results suggest that in X. dendrorhous, ergosterol regulates HMGR gene expression by a negative feedback mechanism and in this way; it contributes in the regulation of the carotenoid biosynthesis.

  17. Disruption of the Acyl-CoA binding protein gene delays hepatic adaptation to metabolic changes at weaning

    DEFF Research Database (Denmark)

    Neess, Ditte; Marcher, Ann-Britt; Bloksgaard, Maria

    The acyl-CoA binding protein/diazepam binding inhibitor (ACBP/DBI) is an evolutionary conserved intracellular protein that binds C14-C22 acyl-CoA esters with very high affinity. ACBP is thought to act as an acyl-CoA transporter, and in vitro analyses have indicated that ACBP can transport acyl......-CoA esters between different enzymatic systems. However, little is known about the in vivo function in mammalian cells. We have generated mice with targeted disruption of ACBP (ACBP-/-). These mice are viable and fertile and develop normally. However, around weaning the ACBP-/- mice show decreased growth......) family, around the weaning period. As a result, the hepatic de novo cholesterogenesis is significantly decreased at weaning. The delayed induction of SREBP target genes around weaning is caused by a compromised processing and decreased expression of SREBP precursors leading to reduced binding of SREBP...

  18. Disruption of the yeast ATH1 gene confers better survival after dehydration, freezing, and ethanol shock: potential commercial applications.

    Science.gov (United States)

    Kim, J; Alizadeh, P; Harding, T; Hefner-Gravink, A; Klionsky, D J

    1996-01-01

    The accumulation of trehalose is a critical determinant of stress resistance in the yeast Saccharomyces cerevisiae. We have constructed a yeast strain in which the activity of the trehalose-hydrolyzing enzyme, acid trehalase (ATH), has been abolished. Loss of ATH activity was accomplished by disrupting the ATH1 gene, which is essential for ATH activity. The delta ath1 strain accumulated greater levels of cellular trehalose and grew to a higher cell density than the isogenic wild-type strain. In addition, the elevated levels of trehalose in the delta ath1 strain correlated with increased tolerance to dehydration, freezing, and toxic levels of ethanol. The improved resistance to stress conditions exhibited by the delta ath1 strain may make this strain useful in commercial applications, including baking and brewing. PMID:8633854

  19. Disruption of the GH Receptor Gene in Adult Mice Increases Maximal Lifespan in Females

    DEFF Research Database (Denmark)

    Junnila, Riia K.; Duran-Ortiz, Silvana; Suer, Ozan

    2016-01-01

    GH and IGF-1 are important for a variety of physiological processes including growth, development, and aging. Mice with reduced levels of GH and IGF-1 have been shown to live longer than wild-type controls. Our laboratory has previously found that mice with a GH receptor gene knockout (GHRKO) fro...

  20. A constitutional translocation t(1;17(p36.2;q11.2 in a neuroblastoma patient disrupts the human NBPF1 and ACCN1 genes.

    Directory of Open Access Journals (Sweden)

    Karl Vandepoele

    Full Text Available The human 1p36 region is deleted in many different types of tumors, and so it probably harbors one or more tumor suppressor genes. In a Belgian neuroblastoma patient, a constitutional balanced translocation t(1;17(p36.2;q11.2 may have led to the development of the tumor by disrupting or activating a gene. Here, we report the cloning of both translocation breakpoints and the identification of a novel gene that is disrupted by this translocation. This gene, named NBPF1 for Neuroblastoma BreakPoint Family member 1, belongs to a recently described gene family encoding highly similar proteins, the functions of which are unknown. The translocation truncates NBPF1 and gives rise to two chimeric transcripts of NBPF1 sequences fused to sequences derived from chromosome 17. On chromosome 17, the translocation disrupts one of the isoforms of ACCN1, a potential glioma tumor suppressor gene. Expression of the NBPF family in neuroblastoma cell lines is highly variable, but it is decreased in cell lines that have a deletion of chromosome 1p. More importantly, expression profiling of the NBPF1 gene showed that its expression is significantly lower in cell lines with heterozygous NBPF1 loss than in cell lines with a normal 1p chromosome. Meta-analysis of the expression of NBPF and ACCN1 in neuroblastoma tumors indicates a role for the NBPF genes and for ACCN1 in tumor aggressiveness. Additionally, DLD1 cells with inducible NBPF1 expression showed a marked decrease of clonal growth in a soft agar assay. The disruption of both NBPF1 and ACCN1 genes in this neuroblastoma patient indicates that these genes might suppress development of neuroblastoma and possibly other tumor types.

  1. Disruption of the Sec24d gene results in early embryonic lethality in the mouse.

    Directory of Open Access Journals (Sweden)

    Andrea C Baines

    Full Text Available Transport of newly synthesized proteins from the endoplasmic reticulum (ER to the Golgi is mediated by the coat protein complex COPII. The inner coat of COPII is assembled from heterodimers of SEC23 and SEC24. Though mice with mutations in one of the four Sec24 paralogs, Sec24b, exhibit a neural tube closure defect, deficiency in humans or mice has not yet been described for any of the other Sec24 paralogs. We now report characterization of mice with targeted disruption of Sec24d. Early embryonic lethality is observed in mice completely deficient in SEC24D, while a hypomorphic Sec24d allele permits survival to mid-embryogenesis. Mice haploinsufficient for Sec24d exhibit no phenotypic abnormality. A BAC transgene containing Sec24d rescues the embryonic lethality observed in Sec24d-null mice. These results demonstrate an absolute requirement for SEC24D expression in early mammalian development that is not compensated by the other three Sec24 paralogs. The early embryonic lethality resulting from loss of SEC24D in mice contrasts with the previously reported mild skeletal phenotype of SEC24D deficiency in zebrafish and restricted neural tube phenotype of SEC24B deficiency in mice. Taken together, these observations suggest that the multiple Sec24 paralogs have developed distinct functions over the course of vertebrate evolution.

  2. Efficient immunoglobulin gene disruption and targeted replacement in rabbit using zinc finger nucleases.

    Directory of Open Access Journals (Sweden)

    Tatiana Flisikowska

    Full Text Available Rabbits are widely used in biomedical research, yet techniques for their precise genetic modification are lacking. We demonstrate that zinc finger nucleases (ZFNs introduced into fertilized oocytes can inactivate a chosen gene by mutagenesis and also mediate precise homologous recombination with a DNA gene-targeting vector to achieve the first gene knockout and targeted sequence replacement in rabbits. Two ZFN pairs were designed that target the rabbit immunoglobulin M (IgM locus within exons 1 and 2. ZFN mRNAs were microinjected into pronuclear stage fertilized oocytes. Founder animals carrying distinct mutated IgM alleles were identified and bred to produce offspring. Functional knockout of the immunoglobulin heavy chain locus was confirmed by serum IgM and IgG deficiency and lack of IgM(+ and IgG(+ B lymphocytes. We then tested whether ZFN expression would enable efficient targeted sequence replacement in rabbit oocytes. ZFN mRNA was co-injected with a linear DNA vector designed to replace exon 1 of the IgM locus with ∼1.9 kb of novel sequence. Double strand break induced targeted replacement occurred in up to 17% of embryos and in 18% of fetuses analyzed. Two major goals have been achieved. First, inactivation of the endogenous IgM locus, which is an essential step for the production of therapeutic human polyclonal antibodies in the rabbit. Second, establishing efficient targeted gene manipulation and homologous recombination in a refractory animal species. ZFN mediated genetic engineering in the rabbit and other mammals opens new avenues of experimentation in immunology and many other research fields.

  3. A model for obesity and gigantism due to disruption of the Ankrd26 gene.

    Science.gov (United States)

    Bera, Tapan K; Liu, Xiu-Fen; Yamada, Masanori; Gavrilova, Oksana; Mezey, Eva; Tessarollo, Lino; Anver, Miriam; Hahn, Yoonsoo; Lee, Byungkook; Pastan, Ira

    2008-01-08

    Obesity is a major health hazard that is caused by a combination of genetic and behavioral factors. Several models of obesity have been described in mice that have defects in the production of peptide hormones, in the function of cell membrane receptors, or in a transcription factor required for neuronal cell development. We have been investigating the function of a family of genes (POTE and ANKRD26) that encode proteins that are associated with the inner aspect of the cell membrane and that contain both ankyrin repeats and spectrin helices, motifs known to interact with signaling proteins in the cell. To assess the function of ANKRD26, we prepared a mutant mouse with partial inactivation of the Ankrd26 gene. We find that the homozygous mutant mice develop extreme obesity, insulin resistance, and an increase in body size. The obesity is associated with hyperphagia with no reduction in energy expenditure and activity. The Ankrd26 protein is expressed in the arcuate and ventromedial nuclei within the hypothalamus and in the ependyma and the circumventricular organs that act as an interface between the peripheral circulation and the brain. In the enlarged hearts of the mutant mice, the levels of both phospho-Akt and mTOR were elevated. These results show that alterations in an unidentified gene can lead to obesity and identify a molecular target for the treatment of obesity.

  4. DISRUPTION OF ARABIDOPSIS RETICULON GENE RTNLB16 RESULTS IN CHLOROPLAST DYSFUNCTION AND OXIDATIVE STRESS

    Directory of Open Access Journals (Sweden)

    Tarasenko V.I.

    2012-08-01

    Full Text Available Reticulons (RTNs are endoplasmic reticulum (ER-localized proteins that have recently attracted much attention. RTNs are ubiquitous proteins present in all eukaryotic organisms examined so far. In animal and yeast, in which knowledge of this protein family is more advanced, RTNs are involved in numerous cellular processes such as apoptosis, cell division and intracellular trafficking. Up to now, a little attention has been paid to their plant counterparts, RTNLBs. Meanwhile, gene search across sequenced genomes revealed that the RTN gene family is more diverse and numerous in plants than in animals and yeasts, which possibly suggests existence of functions specific for plant RTNs. Recently, the localization in different ER regions was shown for two members of plant reticulon family. The location in close proximity to chloroplast membrane was revealed for one of RTNLBs, which is argument in favor of its role in interorganellar interactions. In spite of growing interest towards to plant RTNs, there are no investigations devoted to insertion mutagenesis of genes encoding these proteins. We have genotyped an Arabidopsis line containing T-DNA insertion in RTNLB16 gene encoding uncharacterized member of RTNLB family. The obtained homozygous plants have marked phenotype expressed in a decreased growth rate and a pale-green leaf color. The leaf total chlorophyll content as well as the chlorophyll a/b ratio was significantly lower in mutant plants. It is interesting to note that the extent of phenotypic expression depended on a light intensity. The growth rate of wild-type and mutant plants was the same in low light conditions. The growth rate was significantly decreased and chlorophyll content was 3-5-fold lower in mutant plants growing under moderate light conditions. The growing of plants under high light conditions led to halted growth and death of mutants on the seedling stage. The demonstrated phenotype probably points out to a chloroplast

  5. The Growth Hormone Receptor Gene-Disrupted (GHR-KO) Mouse Fails to Respond to an Intermittent Fasting (IF) Diet

    Science.gov (United States)

    Arum, Oge; Bonkowski, Michael S.; Rocha, Juliana S.; Bartke, Andrzej

    2009-01-01

    SUMMARY The interaction of longevity-conferring genes with longevity-conferring diets is poorly understood. The growth hormone receptor gene-disrupted (GHR-KO) mouse is long-lived; and this longevity is not responsive to 30% caloric restriction (CR), in contrast to wild-type animals from the same strain. To determine whether this may have been limited to a particular level of dietary restriction (DR), we subjected GHR-KO mice to a different dietary restriction regimen, an intermittent fasting (IF) diet. The IF diet increased the survivorship and improved insulin sensitivity of normal males, but failed to affect either parameter in GHR-KO mice. From the results of two paradigms of dietary restriction we postulate that GHR-KO mice would be resistant to any manner of DR; potentially due to their inability to further enhance insulin sensitivity. Insulin sensitivity may be a mechanism and/or a marker of the lifespan-extending potential of an intervention. PMID:19747233

  6. Transposon-mediated random gene disruption with moderate halophilic bacteria and its application for halophilic bacterial siderophore analysis.

    Science.gov (United States)

    Matsui, Toru; Nishino, Tomohiko

    2016-12-01

    Analytical conditions using chromo azurol S was validated for quantification of siderophore in aqueous samples, followed by the characterization of siderophore derived from newly isolated moderately halophilic bacteria. Conditions with good linearity between the absorbance and the siderophore concentration were obtained at a siderophore concentration less than 20 µM, in the wavelength range between 630 and 660 nm with developing time for at least 2 h. Of the halophilic bacteria isolated from Tunisian soil, Halomonas sp., namely strain 21a was selected as siderophore producing halophiles. The strain produced siderophore significantly in the absence of iron in minimal medium. Siderophore-deficient mutant, namely IIa10, of the strain 21a was obtained from gene disruptant library constructed using transposon complex by electroporation. Genomic sequence analysis of the mutant IIa10 revealed that the transposon-inserted gene was TonB-dependent receptor. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Disruption of the novel gene fad104 causes rapid postnatal death and attenuation of cell proliferation, adhesion, spreading and migration

    International Nuclear Information System (INIS)

    Nishizuka, Makoto; Kishimoto, Keishi; Kato, Ayumi; Ikawa, Masahito; Okabe, Masaru; Sato, Ryuichiro; Niida, Hiroyuki; Nakanishi, Makoto; Osada, Shigehiro; Imagawa, Masayoshi

    2009-01-01

    The molecular mechanisms at the beginning of adipogenesis remain unknown. Previously, we identified a novel gene, fad104 (factor for adipocyte differentiation 104), transiently expressed at the early stage of adipocyte differentiation. Since the knockdown of the expression of fad104 dramatically repressed adipogenesis, it is clear that fad104 plays important roles in adipocyte differentiation. However, the physiological roles of fad104 are still unknown. In this study, we generated fad104-deficient mice by gene targeting. Although the mice were born in the expected Mendelian ratios, all died within 1 day of birth, suggesting fad104 to be crucial for survival after birth. Furthermore, analyses of mouse embryonic fibroblasts (MEFs) prepared from fad104-deficient mice provided new insights into the functions of fad104. Disruption of fad104 inhibited adipocyte differentiation and cell proliferation. In addition, cell adhesion and wound healing assays using fad104-deficient MEFs revealed that loss of fad104 expression caused a reduction in stress fiber formation, and notably delayed cell adhesion, spreading and migration. These results indicate that fad104 is essential for the survival of newborns just after birth and important for cell proliferation, adhesion, spreading and migration

  8. Disruption of Slc52a3 gene causes neonatal lethality with riboflavin deficiency in mice

    OpenAIRE

    Yoshimatsu, Hiroki; Yonezawa, Atsushi; Yamanishi, Kaori; Yao, Yoshiaki; Sugano, Kumiko; Nakagawa, Shunsaku; Imai, Satoshi; Omura, Tomohiro; Nakagawa, Takayuki; Yano, Ikuko; Masuda, Satohiro; Inui, Ken-ichi; Matsubara, Kazuo

    2016-01-01

    Homeostasis of riboflavin should be maintained by transporters. Previous in vitro studies have elucidated basic information about riboflavin transporter RFVT3 encoded by SLC52A3 gene. However, the contribution of RFVT3 to the maintenance of riboflavin homeostasis and the significance in vivo remain unclear. Here, we investigated the physiological role of RFVT3 using Slc52a3 knockout (Slc52a3−/−) mice. Most Slc52a3−/− mice died with hyperlipidemia and hypoglycemia within 48 hr after birth. The...

  9. TALEN-based gene disruption in the dengue vector Aedes aegypti.

    Science.gov (United States)

    Aryan, Azadeh; Anderson, Michelle A E; Myles, Kevin M; Adelman, Zach N

    2013-01-01

    In addition to its role as the primary vector for dengue viruses, Aedes aegypti has a long history as a genetic model organism for other bloodfeeding mosquitoes, due to its ease of colonization, maintenance and reproductive productivity. Though its genome has been sequenced, functional characterization of many Ae. aegypti genes, pathways and behaviors has been slow. TALE nucleases (TALENs) have been used with great success in a number of organisms to generate site-specific DNA lesions. We evaluated the ability of a TALEN pair to target the Ae. aegypti kmo gene, whose protein product is essential in the production of eye pigmentation. Following injection into pre-blastoderm embryos, 20-40% of fertile survivors produced kmo alleles that failed to complement an existing kh(w) mutation. Most of these individuals produced more than 20% white-eyed progeny, with some producing up to 75%. Mutant alleles were associated with lesions of 1-7 bp specifically at the selected target site. White-eyed individuals could also be recovered following a blind intercross of G1 progeny, yielding several new white-eyed strains in the genetic background of the sequenced Liverpool strain. We conclude that TALENs are highly active in the Ae. aegypti germline, and have the potential to transform how reverse genetic experiments are performed in this important disease vector.

  10. TALEN-Based Gene Disruption in the Dengue Vector Aedes aegypti

    Science.gov (United States)

    Aryan, Azadeh; Anderson, Michelle A. E.; Myles, Kevin M.; Adelman, Zach N.

    2013-01-01

    In addition to its role as the primary vector for dengue viruses, Aedes aegypti has a long history as a genetic model organism for other bloodfeeding mosquitoes, due to its ease of colonization, maintenance and reproductive productivity. Though its genome has been sequenced, functional characterization of many Ae. aegypti genes, pathways and behaviors has been slow. TALE nucleases (TALENs) have been used with great success in a number of organisms to generate site-specific DNA lesions. We evaluated the ability of a TALEN pair to target the Ae. aegypti kmo gene, whose protein product is essential in the production of eye pigmentation. Following injection into pre-blastoderm embryos, 20–40% of fertile survivors produced kmo alleles that failed to complement an existing khw mutation. Most of these individuals produced more than 20% white-eyed progeny, with some producing up to 75%. Mutant alleles were associated with lesions of 1–7 bp specifically at the selected target site. White-eyed individuals could also be recovered following a blind intercross of G1 progeny, yielding several new white-eyed strains in the genetic background of the sequenced Liverpool strain. We conclude that TALENs are highly active in the Ae. aegypti germline, and have the potential to transform how reverse genetic experiments are performed in this important disease vector. PMID:23555893

  11. TALEN-based gene disruption in the dengue vector Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Azadeh Aryan

    Full Text Available In addition to its role as the primary vector for dengue viruses, Aedes aegypti has a long history as a genetic model organism for other bloodfeeding mosquitoes, due to its ease of colonization, maintenance and reproductive productivity. Though its genome has been sequenced, functional characterization of many Ae. aegypti genes, pathways and behaviors has been slow. TALE nucleases (TALENs have been used with great success in a number of organisms to generate site-specific DNA lesions. We evaluated the ability of a TALEN pair to target the Ae. aegypti kmo gene, whose protein product is essential in the production of eye pigmentation. Following injection into pre-blastoderm embryos, 20-40% of fertile survivors produced kmo alleles that failed to complement an existing kh(w mutation. Most of these individuals produced more than 20% white-eyed progeny, with some producing up to 75%. Mutant alleles were associated with lesions of 1-7 bp specifically at the selected target site. White-eyed individuals could also be recovered following a blind intercross of G1 progeny, yielding several new white-eyed strains in the genetic background of the sequenced Liverpool strain. We conclude that TALENs are highly active in the Ae. aegypti germline, and have the potential to transform how reverse genetic experiments are performed in this important disease vector.

  12. Disrupted auto-regulation of the spliceosomal gene SNRPB causes cerebro–costo–mandibular syndrome

    Science.gov (United States)

    Lynch, Danielle C.; Revil, Timothée; Schwartzentruber, Jeremy; Bhoj, Elizabeth J.; Innes, A. Micheil; Lamont, Ryan E.; Lemire, Edmond G.; Chodirker, Bernard N.; Taylor, Juliet P.; Zackai, Elaine H.; McLeod, D. Ross; Kirk, Edwin P.; Hoover-Fong, Julie; Fleming, Leah; Savarirayan, Ravi; Boycott, Kym; MacKenzie, Alex; Brudno, Michael; Bulman, Dennis; Dyment, David; Majewski, Jacek; Jerome-Majewska, Loydie A.; Parboosingh, Jillian S.; Bernier, Francois P.

    2014-01-01

    Elucidating the function of highly conserved regulatory sequences is a significant challenge in genomics today. Certain intragenic highly conserved elements have been associated with regulating levels of core components of the spliceosome and alternative splicing of downstream genes. Here we identify mutations in one such element, a regulatory alternative exon of SNRPB as the cause of cerebro–costo–mandibular syndrome. This exon contains a premature termination codon that triggers nonsense-mediated mRNA decay when included in the transcript. These mutations cause increased inclusion of the alternative exon and decreased overall expression of SNRPB. We provide evidence for the functional importance of this conserved intragenic element in the regulation of alternative splicing and development, and suggest that the evolution of such a regulatory mechanism has contributed to the complexity of mammalian development. PMID:25047197

  13. Disrupted auto-regulation of the spliceosomal gene SNRPB causes cerebro-costo-mandibular syndrome.

    Science.gov (United States)

    Lynch, Danielle C; Revil, Timothée; Schwartzentruber, Jeremy; Bhoj, Elizabeth J; Innes, A Micheil; Lamont, Ryan E; Lemire, Edmond G; Chodirker, Bernard N; Taylor, Juliet P; Zackai, Elaine H; McLeod, D Ross; Kirk, Edwin P; Hoover-Fong, Julie; Fleming, Leah; Savarirayan, Ravi; Majewski, Jacek; Jerome-Majewska, Loydie A; Parboosingh, Jillian S; Bernier, Francois P

    2014-07-22

    Elucidating the function of highly conserved regulatory sequences is a significant challenge in genomics today. Certain intragenic highly conserved elements have been associated with regulating levels of core components of the spliceosome and alternative splicing of downstream genes. Here we identify mutations in one such element, a regulatory alternative exon of SNRPB as the cause of cerebro-costo-mandibular syndrome. This exon contains a premature termination codon that triggers nonsense-mediated mRNA decay when included in the transcript. These mutations cause increased inclusion of the alternative exon and decreased overall expression of SNRPB. We provide evidence for the functional importance of this conserved intragenic element in the regulation of alternative splicing and development, and suggest that the evolution of such a regulatory mechanism has contributed to the complexity of mammalian development.

  14. Targeted disruption of the biglycan gene leads to an osteoporosis-like phenotype in mice

    DEFF Research Database (Denmark)

    Xu, T; Bianco, P; Fisher, L W

    1998-01-01

    The resilience and strength of bone is due to the orderly mineralization of a specialized extracellular matrix (ECM) composed of type I collagen (90%) and a host of non-collagenous proteins that are, in general, also found in other tissues. Biglycan (encoded by the gene Bgn) is an ECM proteoglycan...... apparently normal at birth, these mice display a phenotype characterized by a reduced growth rate and decreased bone mass due to the absence of Bgn. To our knowledge, this is the first report in which deficiency of a non-collagenous ECM protein leads to a skeletal phenotype that is marked by low bone mass...... that becomes more obvious with age. These mice may serve as an animal model to study the role of ECM proteins in osteoporosis....

  15. Novel drug targets in cell wall biosynthesis exploited by gene disruption in Pseudomonas aeruginosa.

    Science.gov (United States)

    Elamin, Ayssar A; Steinicke, Susanne; Oehlmann, Wulf; Braun, Yvonne; Wanas, Hanaa; Shuralev, Eduard A; Huck, Carmen; Maringer, Marko; Rohde, Manfred; Singh, Mahavir

    2017-01-01

    For clinicians, Pseudomonas aeruginosa is a nightmare pathogen that is one of the top three causes of opportunistic human infections. Therapy of P. aeruginosa infections is complicated due to its natural high intrinsic resistance to antibiotics. Active efflux and decreased uptake of drugs due to cell wall/membrane permeability appear to be important issues in the acquired antibiotic tolerance mechanisms. Bacterial cell wall biosynthesis enzymes have been shown to be essential for pathogenicity of Gram-negative bacteria. However, the role of these targets in virulence has not been identified in P. aeruginosa. Here, we report knockout (k.o) mutants of six cell wall biosynthesis targets (murA, PA4450; murD, PA4414; murF, PA4416; ppiB, PA1793; rmlA, PA5163; waaA, PA4988) in P. aeruginosa PAO1, and characterized these in order to find out whether these genes and their products contribute to pathogenicity and virulence of P. aeruginosa. Except waaA k.o, deletion of cell wall biosynthesis targets significantly reduced growth rate in minimal medium compared to the parent strain. The k.o mutants showed exciting changes in cell morphology and colonial architectures. Remarkably, ΔmurF cells became grossly enlarged. Moreover, the mutants were also attenuated in vivo in a mouse infection model except ΔmurF and ΔwaaA and proved to be more sensitive to macrophage-mediated killing than the wild-type strain. Interestingly, the deletion of the murA gene resulted in loss of virulence activity in mice, and the virulence was restored in a plant model by unknown mechanism. This study demonstrates that cell wall targets contribute significantly to intracellular survival, in vivo growth, and pathogenesis of P. aeruginosa. In conclusion, these findings establish a link between cell wall targets and virulence of P. aeruginosa and thus may lead to development of novel drugs for the treatment of P. aeruginosa infection.

  16. Incorrect dosage of IQSEC2, a known intellectual disability and epilepsy gene, disrupts dendritic spine morphogenesis

    Science.gov (United States)

    Hinze, S J; Jackson, M R; Lie, S; Jolly, L; Field, M; Barry, S C; Harvey, R J; Shoubridge, C

    2017-01-01

    There is considerable genetic and phenotypic heterogeneity associated with intellectual disability (ID), specific learning disabilities, attention-deficit hyperactivity disorder, autism and epilepsy. The intelligence quotient (IQ) motif and SEC7 domain containing protein 2 gene (IQSEC2) is located on the X-chromosome and harbors mutations that contribute to non-syndromic ID with and without early-onset seizure phenotypes in both sexes. Although IQ and Sec7 domain mutations lead to partial loss of IQSEC2 enzymatic activity, the in vivo pathogenesis resulting from these mutations is not known. Here we reveal that IQSEC2 has a key role in dendritic spine morphology. Partial loss-of-function mutations were modeled using a lentiviral short hairpin RNA (shRNA) approach, which achieved a 57% knockdown of Iqsec2 expression in primary hippocampal cell cultures from mice. Investigating gross morphological parameters after 8 days of in vitro culture (8DIV) identified a 32% reduction in primary axon length, in contrast to a 27% and 31% increase in the number and complexity of dendrites protruding from the cell body, respectively. This increase in dendritic complexity and spread was carried through dendritic spine development, with a 34% increase in the number of protrusions per dendritic segment compared with controls at 15DIV. Although the number of dendritic spines had normalized by 21DIV, a reduction was noted in the number of immature spines. In contrast, when modeling increased dosage, overexpression of wild-type IQSEC2 led to neurons with shorter axons that were more compact and displayed simpler dendritic branching. Disturbances to dendritic morphology due to knockdown of Iqsec2 were recapitulated in neurons from Iqsec2 knockout mice generated in our laboratory using CRISPR/Cas9 technology. These observations provide evidence of dosage sensitivity for IQSEC2, which normally escapes X-inactivation in females, and links these disturbances in expression to alterations in

  17. A Simple and Rapid Gene Disruption Strategy in Mycobacterium abscessus: On the Design and Application of Glycopeptidolipid Mutants.

    Science.gov (United States)

    Viljoen, Albertus; Gutiérrez, Ana Victoria; Dupont, Christian; Ghigo, Eric; Kremer, Laurent

    2018-01-01

    Little is known about the disease-causing genetic determinants that are used by Mycobacterium abscessus , increasingly acknowledged as an important emerging pathogen, notably in cystic fibrosis. The presence or absence of surface exposed glycopeptidolipids (GPL) conditions the smooth (S) or rough (R) M. abscessus subsp. abscessus ( M. abscessus ) variants, respectively, which are characterized by distinct infective programs. However, only a handful of successful gene knock-out and conditional mutants have been reported in M. abscessus , testifying that genetic manipulation of this mycobacterium is difficult. To facilitate gene disruption and generation of conditional mutants in M. abscessus , we have designed a one-step single cross-over system that allows the rapid and simple generation of such mutants. Cloning of as small as 300 bp of the target gene allows for efficient homologous recombination to occur without additional exogenous recombination-promoting factors. The presence of tdTomato on the plasmids allows easily sifting out the large background of mutants spontaneously resistant to antibiotics. Using this strategy in the S genetic background and the target gene mmpL4a , necessary for GPL synthesis and transport, nearly 100% of red fluorescent clones exhibited a rough morphotype and lost GPL on the surface, suggesting that most red fluorescent colonies obtained after transformation incorporated the plasmid through homologous recombination into the chromosome. This system was further exploited to generate another strain with reduced GPL levels to explore how the presence of these cell wall-associated glycolipids influences M. abscessus hydrophobicity as well as virulence in the zebrafish model of infection. This mutant exhibited a more pronounced killing phenotype in zebrafish embryos compared to its S progenitor and this effect correlated with the production of abscesses in the central nervous system. Overall, these results suggest that the near

  18. Disruption of each of the secreted aspartyl proteinase genes SAP1, SAP2, and SAP3 of Candida albicans attenuates virulence.

    OpenAIRE

    Hube, B; Sanglard, D; Odds, F C; Hess, D; Monod, M; Schäfer, W; Brown, A J; Gow, N A

    1997-01-01

    Secreted aspartyl proteinases (Saps), encoded by a gene family with at least nine members (SAP1 to SAP9), are one of the most discussed virulence factors produced by the human pathogen Candida albicans. In order to study the role of each Sap isoenzyme in pathogenicity, we have constructed strains which harbor mutations at selected SAP genes. SAP1, SAP2, and SAP3, which are regulated differentially in vitro, were mutated by targeted gene disruption. The growth rates of all homozygous null muta...

  19. Genetic Disruption of the Sh3pxd2a Gene Reveals an Essential Role in Mouse Development and the Existence of a Novel Isoform of Tks5

    OpenAIRE

    Cejudo-Martin, Pilar; Yuen, Angela; Vlahovich, Nicole; Lock, Peter; Courtneidge, Sara A.; Díaz, Begoña

    2014-01-01

    Tks5 is a scaffold protein and Src substrate involved in cell migration and matrix degradation through its essential role in invadosome formation and function. We have previously described that Tks5 is fundamental for zebrafish neural crest cell migration in vivo. In the present study, we sought to investigate the function of Tks5 in mammalian development by analyzing mice mutant for sh3pxd2a, the gene encoding Tks5. Homozygous disruption of the sh3pxd2a gene by gene-trapping in mouse resulte...

  20. High contaminant loads in Lake Apopka's riparian wetland disrupt gene networks involved in reproduction and immune function in largemouth bass.

    Science.gov (United States)

    Martyniuk, Christopher J; Doperalski, Nicholas J; Prucha, Melinda S; Zhang, Ji-Liang; Kroll, Kevin J; Conrow, Roxanne; Barber, David S; Denslow, Nancy D

    2016-09-01

    Lake Apopka (FL, USA) has elevated levels of some organochlorine pesticides in its sediments and a portion of its watershed has been designated a US Environmental Protection Agency Superfund site. This study assessed reproductive endpoints in Florida largemouth bass (LMB) (Micropterus salmoides floridanus) after placement into experimental ponds adjacent to Lake Apopka. LMB collected from a clean reference site (DeLeon Springs) were stocked at two periods of time into ponds constructed in former farm fields on the north shore of the lake. LMB were stocked during early and late oogenesis to determine if there were different effects of contamination on LMB that may be attributed to their reproductive stage. LMB inhabiting the ponds for ~4months had anywhere from 2 to 800 times higher contaminant load for a number of organochlorine pesticides (e.g. p, p'-DDE, methoxychlor) compared to control animals. Gonadosomatic index and plasma vitellogenin were not different between reproductively-stage matched LMB collected at reference sites compared to those inhabiting the ponds. However, plasma 17β-estradiol was lower in LMB inhabiting the Apopka ponds compared to ovary stage-matched LMB from the St. Johns River, a site used as a reference site. Sub-network enrichment analysis revealed that genes related to reproduction (granulosa function, oocyte development), endocrine function (steroid metabolism, hormone biosynthesis), and immune function (T cell suppression, leukocyte accumulation) were differentially expressed in the ovaries of LMB placed into the ponds. These data suggest that (1) LMB inhabiting the Apopka ponds showed disrupted reproduction and immune responses and that (2) gene expression profiles provided site-specific information by discriminating LMB from different macro-habitats. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Disruption of a CAROTENOID CLEAVAGE DIOXYGENASE 4 gene converts flower colour from white to yellow in Brassica species.

    Science.gov (United States)

    Zhang, Bao; Liu, Chao; Wang, Yaqin; Yao, Xuan; Wang, Fang; Wu, Jiangsheng; King, Graham J; Liu, Kede

    2015-06-01

    In Brassica napus, yellow petals had a much higher content of carotenoids than white petals present in a small number of lines, with violaxanthin identified as the major carotenoid compound in yellow petals of rapeseed lines. Using positional cloning we identified a carotenoid cleavage dioxygenase 4 gene, BnaC3.CCD4, responsible for the formation of flower colour, with preferential expression in petals of white-flowered B. napus lines. Insertion of a CACTA-like transposable element 1 (TE1) into the coding region of BnaC3.CCD4 had disrupted its expression in yellow-flowered rapeseed lines. α-Ionone was identified as the major volatile apocarotenoid released from white petals but not from yellow petals. We speculate that BnaC3.CCD4 may use δ- and/or α-carotene as substrates. Four variations, including two CACTA-like TEs (alleles M1 and M4) and two insertion/deletions (INDELs, alleles M2 and M3), were identified in yellow-flowered Brassica oleracea lines. The two CACTA-like TEs were also identified in the coding region of BcaC3.CCD4 in Brassica carinata. However, the two INDELs were not detected in B. napus and B. carinata. We demonstrate that the insertions of TEs in BolC3.CCD4 predated the formation of the two allotetraploids. © 2015 The Authors New Phytologist © 2015 New Phytologist Trust.

  2. Human iPSC-Derived Cerebellar Neurons from a Patient with Ataxia-Telangiectasia Reveal Disrupted Gene Regulatory Networks

    Directory of Open Access Journals (Sweden)

    Sam P. Nayler

    2017-10-01

    Full Text Available Ataxia-telangiectasia (A-T is a rare genetic disorder caused by loss of function of the ataxia-telangiectasia-mutated kinase and is characterized by a predisposition to cancer, pulmonary disease, immune deficiency and progressive degeneration of the cerebellum. As animal models do not faithfully recapitulate the neurological aspects, it remains unclear whether cerebellar degeneration is a neurodevelopmental or neurodegenerative phenotype. To address the necessity for a human model, we first assessed a previously published protocol for the ability to generate cerebellar neuronal cells, finding it gave rise to a population of precursors highly enriched for markers of the early hindbrain such as EN1 and GBX2, and later more mature cerebellar markers including PTF1α, MATH1, HOXB4, ZIC3, PAX6, and TUJ1. RNA sequencing was used to classify differentiated cerebellar neurons generated from integration-free A-T and control induced pluripotent stem cells. Comparison of RNA sequencing data with datasets from the Allen Brain Atlas reveals in vitro-derived cerebellar neurons are transcriptionally similar to discrete regions of the human cerebellum, and most closely resemble the cerebellum at 22 weeks post-conception. We show that patient-derived cerebellar neurons exhibit disrupted gene regulatory networks associated with synaptic vesicle dynamics and oxidative stress, offering the first molecular insights into early cerebellar pathogenesis of ataxia-telangiectasia.

  3. CCR5 Gene Disruption via Lentiviral Vectors Expressing Cas9 and Single Guided RNA Renders Cells Resistant to HIV-1 Infection

    Science.gov (United States)

    Liu, Jingjing; Zhang, Di; Kimata, Jason T.; Zhou, Paul

    2014-01-01

    CCR5, a coreceptor for HIV-1 entry, is a major target for drug and genetic intervention against HIV-1. Genetic intervention strategies have knocked down CCR5 expression levels by shRNA or disrupted the CCR5 gene using zinc finger nucleases (ZFN) or Transcription activator-like effector nuclease (TALEN). In the present study, we silenced CCR5 via CRISPR associated protein 9 (Cas9) and single guided RNAs (sgRNAs). We constructed lentiviral vectors expressing Cas9 and CCR5 sgRNAs. We show that a single round transduction of lentiviral vectors expressing Cas9 and CCR5 sgRNAs into HIV-1 susceptible human CD4+ cells yields high frequencies of CCR5 gene disruption. CCR5 gene-disrupted cells are not only resistant to R5-tropic HIV-1, including transmitted/founder (T/F) HIV-1 isolates, but also have selective advantage over CCR5 gene-undisrupted cells during R5-tropic HIV-1 infection. Importantly, using T7 endonuclease I assay we did not detect genome mutations at potential off-target sites that are highly homologous to these CCR5 sgRNAs in stably transduced cells even at 84 days post transduction. Thus we conclude that silencing of CCR5 via Cas9 and CCR5-specific sgRNAs could be a viable alternative strategy for engineering resistance against HIV-1. PMID:25541967

  4. Further increased production of free fatty acids by overexpressing a predicted transketolase gene of the pentose phosphate pathway in Aspergillus oryzae faaA disruptant.

    Science.gov (United States)

    Tamano, Koichi; Miura, Ai

    2016-09-01

    Free fatty acids are useful as source materials for the production of biodiesel fuel and various chemicals such as pharmaceuticals and dietary supplements. Previously, we attained a 9.2-fold increase in free fatty acid productivity by disrupting a predicted acyl-CoA synthetase gene (faaA, AO090011000642) in Aspergillus oryzae. In this study, we achieved further increase in the productivity by overexpressing a predicted transketolase gene of the pentose phosphate pathway in the faaA disruptant. The A. oryzae genome is predicted to have three transketolase genes and overexpression of AO090023000345, one of the three genes, resulted in phenotypic change and further increase (corresponding to an increased production of 0.38 mmol/g dry cell weight) in free fatty acids at 1.4-fold compared to the faaA disruptant. Additionally, the biomass of hyphae increased at 1.2-fold by the overexpression. As a result, free fatty acid production yield per liter of liquid culture increased at 1.7-fold by the overexpression.

  5. Disruption of the ndhF1 gene affects Chl fluorescence through state transition in the Cyanobacterium Synechocystis sp. PCC 6803, resulting in apparent high efficiency of photosynthesis.

    Science.gov (United States)

    Ogawa, Takako; Harada, Tetsuyuki; Ozaki, Hiroshi; Sonoike, Kintake

    2013-07-01

    In Synechocystis sp. PCC 6803, the disruption of the ndhF1 gene (slr0844), which encodes a subunit of one of the NDH-1 complexes (NDH-1L complex) serving for respiratory electron transfer, causes the largest change in Chl fluorescence induction kinetics among the kinetics of 750 disruptants searched in the Fluorome, the cyanobacterial Chl fluorescence database. The cause of the explicit phenotype of the ndhF1 disruptant was examined by measurements of the photosynthetic rate, Chl fluorescence and state transition. The results demonstrate that the defects in respiratory electron transfer obviously have great impact on Chl fluorescence in cyanobacteria. The inactivation of NDH-1L complexes involving electron transfer from NDH-1 to plastoquinone (PQ) would result in the oxidation of the PQ pool, leading to the transition to State 1, where the yield of Chl fluorescence is high. Apparently, respiration, although its rate is far lower than that of photosynthesis, could affect Chl fluorescence through the state transition as leverage. The disruption of the ndhF1 gene caused lower oxygen-evolving activity but the estimated electron transport rate from Chl fluorescence measurements was faster in the mutant than in the wild-type cells. The discrepancy could be ascribed to the decreased level of non-photochemical quenching due to state transition. One must be cautious when using the Chl fluorescence parameter to estimate photosynthesis in mutants defective in state transition.

  6. Disruption of the M2 gene of murine gammaherpesvirus 68 alters splenic latency following intranasal, but not intraperitoneal, inoculation.

    Science.gov (United States)

    Jacoby, Meagan A; Virgin, Herbert W; Speck, Samuel H

    2002-02-01

    Infection of mice with murine gammaherpesvirus 68 (gamma HV68; also referred to as MHV68) provides a tractable small-animal model with which to address the requirements for the establishment and maintenance of gammaherpesvirus infection in vivo. The M2 gene of gamma HV68 is a latency-associated gene that encodes a protein lacking discernible homology to any known viral or cellular proteins. M2 gene transcripts have been detected in latently infected splenocytes (S. M. Husain, E. J. Usherwood, H. Dyson, C. Coleclough, M. A. Coppola, D. L. Woodland, M. A. Blackman, J. P. Stewart, and J. T. Sample, Proc. Natl. Acad. Sci. USA 96:7508-7513, 1999; H. W. Virgin IV, R. M. Presti, X. Y. Li, C. Liu, and S. H. Speck, J. Virol. 73:2321-2332, 1999) and peritoneal exudate cells (H. W. Virgin IV, R. M. Presti, X. Y. Li, C. Liu, and S. H. Speck, J. Virol. 73:2321-2332, 1999), as well as in a latently gamma HV68-infected B-lymphoma cell line (S. M. Husain, E. J. Usherwood, H. Dyson, C. Coleclough, M. A. Coppola, D. L. Woodland, M. A. Blackman, J. P. Stewart, and J. T. Sample, Proc. Natl. Acad. Sci. USA 96:7508-7513, 1999). Here we describe the generation of gamma HV68 mutants with disruptions in the M2 gene. Mutation of the M2 gene did not affect the ability of the virus to replicate in tissue culture, nor did it affect gamma HV68 virulence in B6.Rag1 deficient mice. However, we found that M2 was differentially required for acute replication in vivo. While mutation of M2 did not affect acute phase of virus replication in the lungs of mice following intranasal inoculation, acute-phase virus replication in the spleen was decreased compared to that of the wild-type and marker rescue viruses following intraperitoneal inoculation. Upon intranasal inoculation, M2 mutant viruses exhibited a significant decrease in the establishment of latency in the spleen on day 16 postinfection, as measured by the frequency of viral genome-positive cells. In addition, M2 mutant viral genome

  7. Pectate lyase affects pathogenicity in natural isolates of Colletotrichum coccodes and in pelA gene-disrupted and gene-overexpressing mutant lines.

    Science.gov (United States)

    Ben-Daniel, Bat-Hen; Bar-Zvi, Dudy; Tsror Lahkim, Leah

    2012-02-01

    Colletotrichum coccodes (Wallr.) S. Hughes, the causal agent of black dot on potato and anthracnose on tomato, reduces yield and crop quality. We explored the role of secreted pectate lyase (PL), a cell wall-degrading enzyme, in the aggressiveness of C. coccodes. In vitro-cultivated highly aggressive isolates secreted immunologically detectable PL levels 6 h after transfer to secondary medium versus 12 h for mildly aggressive isolates, suggesting that secreted PL is a virulence factor. The gene encoding PL, CcpelA, was cloned and used for the genetic manipulation of highly (US-41 and Si-72) and mildly (Si-60) aggressive isolates. CcpelA gene-disrupted mutants showed reduced aggressiveness towards tomato fruits and impaired PL secretion and extracellular activity. Conversely, overexpression of CcpelA in the Si-60 isolate increased its aggressiveness and PL secretion. Comparison of CcpelA cloned from isolates US-41 and Si-60 revealed that both encode identical proteins, but differ in their promoters. Bioinformatics analysis for cis-acting elements suggested that the promoters of the US-41 and Si-60 isolates contain one and no AreA-binding site (GATA box), respectively. AreA has been suggested to be involved in fungal aggressiveness; therefore, CcpelA may be a key virulence factor in C. coccodes pathogenicity, and the differences in isolate aggressiveness might result from promoter activity. Quantitative reverse transcriptase-polymerase chain reaction analyses confirmed the higher level of CcpelA transcript in isolate US-41 versus Si-60. © 2011 THE AUTHORS. MOLECULAR PLANT PATHOLOGY © 2011 BSPP AND BLACKWELL PUBLISHING LTD.

  8. Novel Cocaine Vaccine Linked to a Disrupted Adenovirus Gene Transfer Vector Blocks Cocaine Psychostimulant and Reinforcing Effects

    Science.gov (United States)

    Wee, Sunmee; Hicks, Martin J; De, Bishnu P; Rosenberg, Jonathan B; Moreno, Amira Y; Kaminsky, Stephen M; Janda, Kim D; Crystal, Ronald G; Koob, George F

    2012-01-01

    Immunotherapy is a promising treatment for drug addiction. However, insufficient immune responses to vaccines in most subjects pose a challenge. In this study, we tested the efficacy of a new cocaine vaccine (dAd5GNE) in antagonizing cocaine addiction-related behaviors in rats. This vaccine used a disrupted serotype 5 adenovirus (Ad) gene transfer vector coupled to a third-generation cocaine hapten, termed GNE (6-(2R,3S)-3-(benzoyloxy)-8-methyl-8-azabicyclo [3.2.1] octane-2-carboxamido-hexanoic acid). Three groups of rats were immunized with dAd5GNE. One group was injected with 3H-cocaine, and radioactivity in the blood and brain was determined. A second group was tested for cocaine-induced locomotor sensitization. A third group was examined for cocaine self-administration, extinction, and reinstatement of responding for cocaine. Antibody titers were determined at various time-points. In each experiment, we added a control group that was immunized with dAd5 without a hapten. The vaccination with dAd5GNE produced long-lasting high titers (>105) of anti-cocaine antibodies in all of the rats. The vaccination inhibited cocaine-induced hyperlocomotor activity and sensitization. Vaccinated rats acquired cocaine self-administration, but they showed less motivation to self-administer cocaine under a progressive-ratio schedule than control rats. When cocaine was not available in a session, control rats exhibited ‘extinction burst' responding, whereas vaccinated rats did not. Moreover, when primed with cocaine, vaccinated rats did not reinstate responding, suggesting a blockade of cocaine-seeking behavior. These data strongly suggest that our dAd5GNE vector-based vaccine may be effective in treating cocaine abuse and addiction. PMID:21918504

  9. Loss of circadian rhythm of circulating insulin concentration induced by high-fat diet intake is associated with disrupted rhythmic expression of circadian clock genes in the liver.

    Science.gov (United States)

    Honma, Kazue; Hikosaka, Maki; Mochizuki, Kazuki; Goda, Toshinao

    2016-04-01

    Peripheral clock genes show a circadian rhythm is correlated with the timing of feeding in peripheral tissues. It was reported that these clock genes are strongly regulated by insulin action and that a high-fat diet (HFD) intake in C57BL/6J mice for 21days induced insulin secretion during the dark phase and reduced the circadian rhythm of clock genes. In this study, we examined the circadian expression patterns of these clock genes in insulin-resistant animal models with excess secretion of insulin during the day. We examined whether insulin resistance induced by a HFD intake for 80days altered blood parameters (glucose and insulin concentrations) and expression of mRNA and proteins encoded by clock and functional genes in the liver using male ICR mice. Serum insulin concentrations were continuously higher during the day in mice fed a HFD than control mice. Expression of lipogenesis-related genes (Fas and Accβ) and the transcription factor Chrebp peaked at zeitgeber time (ZT)24 in the liver of control mice. A HFD intake reduced the expression of these genes at ZT24 and disrupted the circadian rhythm. Expression of Bmal1 and Clock, transcription factors that compose the core feedback loop, showed circadian variation and were synchronously associated with Fas gene expression in control mice, but not in those fed a HFD. These results indicate that the disruption of the circadian rhythm of insulin secretion by HFD intake is closely associated with the disappearance of circadian expression of lipogenic and clock genes in the liver of mice. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Molecular Characterization of Heterologous HIV-1gp120 Gene Expression Disruption in Mycobacterium bovis BCG Host Strain: A Critical Issue for Engineering Mycobacterial Based-Vaccine Vectors

    Science.gov (United States)

    Joseph, Joan; Fernández-Lloris, Raquel; Pezzat, Elías; Saubi, Narcís; Cardona, Pere-Joan; Mothe, Beatriz; Gatell, Josep Maria

    2010-01-01

    Mycobacterium bovis Bacillus Calmette-Guérin (BCG) as a live vector of recombinant bacterial vaccine is a promising system to be used. In this study, we evaluate the disrupted expression of heterologous HIV-1gp120 gene in BCG Pasteur host strain using replicative vectors pMV261 and pJH222. pJH222 carries a lysine complementing gene in BCG lysine auxotrophs. The HIV-1 gp120 gene expression was regulated by BCG hsp60 promoter (in plasmid pMV261) and Mycobacteria spp. α-antigen promoter (in plasmid pJH222). Among 14 rBCG:HIV-1gp120 (pMV261) colonies screened, 12 showed a partial deletion and two showed a complete deletion. However, deletion was not observed in all 10 rBCG:HIV-1gp120 (pJH222) colonies screened. In this study, we demonstrated that E. coli/Mycobacterial expression vectors bearing a weak promoter and lysine complementing gene in a recombinant lysine auxotroph of BCG could prevent genetic rearrangements and disruption of HIV 1gp120 gene expression, a key issue for engineering Mycobacterial based vaccine vectors. PMID:20617151

  11. Molecular Characterization of Heterologous HIV-1gp120 Gene Expression Disruption in Mycobacterium bovis BCG Host Strain: A Critical Issue for Engineering Mycobacterial Based-Vaccine Vectors

    Directory of Open Access Journals (Sweden)

    Joan Joseph

    2010-01-01

    Full Text Available Mycobacterium bovis Bacillus Calmette-Guérin (BCG as a live vector of recombinant bacterial vaccine is a promising system to be used. In this study, we evaluate the disrupted expression of heterologous HIV-1gp120 gene in BCG Pasteur host strain using replicative vectors pMV261 and pJH222. pJH222 carries a lysine complementing gene in BCG lysine auxotrophs. The HIV-1 gp120 gene expression was regulated by BCG hsp60 promoter (in plasmid pMV261 and Mycobacteria spp. α-antigen promoter (in plasmid pJH222. Among 14 rBCG:HIV-1gp120 (pMV261 colonies screened, 12 showed a partial deletion and two showed a complete deletion. However, deletion was not observed in all 10 rBCG:HIV-1gp120 (pJH222 colonies screened. In this study, we demonstrated that E. coli/Mycobacterial expression vectors bearing a weak promoter and lysine complementing gene in a recombinant lysine auxotroph of BCG could prevent genetic rearrangements and disruption of HIV 1gp120 gene expression, a key issue for engineering Mycobacterial based vaccine vectors.

  12. 17α-Ethinylestradiol (EE2) treatment of wild roach (Rutilus rutilus) during early life development disrupts expression of genes directly involved in the feedback cycle of estrogen.

    Science.gov (United States)

    Nikoleris, Lina; Hultin, Cecilia L; Hallgren, Per; Hansson, Maria C

    2016-02-01

    Fish are more sensitive to introduced disturbances from synthetic endocrine disrupting compounds during early life phases compared with mature stages. 17α-Ethinylestradiol (EE2), which is the active compound in human oral contraceptives and hormone replacement therapies, is today ever present in the effluents from sewage treatment plants. EE2 targets and interacts with the endogenous biological systems of exposed vertebrates resulting in to large extents unknown short- and long-term effects. We investigated how EE2 exposure affects expression profiles of a large number of target genes during early life of roach (Rutilus rutilus). We exposed fertilized roach eggs collected from a lake in Southern Sweden to EE2 for 12weeks together with 1+-year-old roach in aquaria. We measured the gene expression of the estrogen receptor (esr)1/2a/2b, androgen receptor (ar), vitellogenin, cytochrome P450 (cyp)19a1a/1b in fertilized eggs; newly hatched larvae; 12-week-old fry; and juvenile wild roach (1+-year-old). Results shows that an EE2 concentration as low as 0.5ng/L significantly affects gene expression during early development. Gene expression responses vary both among life stages and molecular receptors. We also show that the gene profile of the estrogen feedback cycle to a large extent depends on the relationship between the three esr genes and the two cyp19a1 genes, which are all up-regulated with age. Results indicate that a disruption of the natural activity of the dominant esr gene could lead to detrimental biological effects if EE2 exposure occurs during development, even if this exposure occurred for only a short period. Copyright © 2015. Published by Elsevier Inc.

  13. Disruption of the nitrogen regulatory gene AcareA in Acremonium chrysogenum leads to reduction of cephalosporin production and repression of nitrogen metabolism.

    Science.gov (United States)

    Li, Jinyang; Pan, Yuanyuan; Liu, Gang

    2013-12-01

    AcareA, encoding a homologue of the fungal nitrogen regulatory GATA zinc-finger proteins, was cloned from Acremonium chrysogenum. Gene disruption and genetic complementation revealed that AcareA was required for nitrogen metabolism and cephalosporin production. Disruption of AcareA resulted in growth defect in the medium using nitrate, uric acid and low concentration of ammonium, glutamine or urea as sole nitrogen source. Transcriptional analysis showed that the transcription of niaD/niiA was increased drastically when induced with nitrate in the wild-type and AcareA complemented strains but not in AcareA disruption mutant. Consistent with the reduction of cephalosporin production, the transcription of pcbAB, cefD2, cefEF and cefG encoding the enzymes for cephalosporin production was reduced in AcareA disruption mutant. Band shift assays showed that AcAREA bound to the promoter regions of niaD, niiA and the bidirectional promoter region of pcbAB-pcbC. Sequence analysis showed that all the AcAREA binding sites contain the consensus GATA elements. These results indicated that AcAREA plays an important role both in the regulation of nitrogen metabolism and cephalosporin production in A. chrysogenum. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. An Improved Single-Step Cloning Strategy Simplifies the Agrobacterium tumefaciens-Mediated Transformation (ATMT)-Based Gene-Disruption Method for Verticillium dahliae.

    Science.gov (United States)

    Wang, Sheng; Xing, Haiying; Hua, Chenlei; Guo, Hui-Shan; Zhang, Jie

    2016-06-01

    The soilborne fungal pathogen Verticillium dahliae infects a broad range of plant species to cause severe diseases. The availability of Verticillium genome sequences has provided opportunities for large-scale investigations of individual gene function in Verticillium strains using Agrobacterium tumefaciens-mediated transformation (ATMT)-based gene-disruption strategies. Traditional ATMT vectors require multiple cloning steps and elaborate characterization procedures to achieve successful gene replacement; thus, these vectors are not suitable for high-throughput ATMT-based gene deletion. Several advancements have been made that either involve simplification of the steps required for gene-deletion vector construction or increase the efficiency of the technique for rapid recombinant characterization. However, an ATMT binary vector that is both simple and efficient is still lacking. Here, we generated a USER-ATMT dual-selection (DS) binary vector, which combines both the advantages of the USER single-step cloning technique and the efficiency of the herpes simplex virus thymidine kinase negative-selection marker. Highly efficient deletion of three different genes in V. dahliae using the USER-ATMT-DS vector enabled verification that this newly-generated vector not only facilitates the cloning process but also simplifies the subsequent identification of fungal homologous recombinants. The results suggest that the USER-ATMT-DS vector is applicable for efficient gene deletion and suitable for large-scale gene deletion in V. dahliae.

  15. Circadian clock genes Per1 and Per2 regulate the response of metabolism-associated transcripts to sleep disruption.

    Directory of Open Access Journals (Sweden)

    Jana Husse

    Full Text Available Human and animal studies demonstrate that short sleep or poor sleep quality, e.g. in night shift workers, promote the development of obesity and diabetes. Effects of sleep disruption on glucose homeostasis and liver physiology are well documented. However, changes in adipokine levels after sleep disruption suggest that adipocytes might be another important peripheral target of sleep. Circadian clocks regulate metabolic homeostasis and clock disruption can result in obesity and the metabolic syndrome. The finding that sleep and clock disruption have very similar metabolic effects prompted us to ask whether the circadian clock machinery may mediate the metabolic consequences of sleep disruption. To test this we analyzed energy homeostasis and adipocyte transcriptome regulation in a mouse model of shift work, in which we prevented mice from sleeping during the first six hours of their normal inactive phase for five consecutive days (timed sleep restriction--TSR. We compared the effects of TSR between wild-type and Per1/2 double mutant mice with the prediction that the absence of a circadian clock in Per1/2 mutants would result in a blunted metabolic response to TSR. In wild-types, TSR induces significant transcriptional reprogramming of white adipose tissue, suggestive of increased lipogenesis, together with increased secretion of the adipokine leptin and increased food intake, hallmarks of obesity and associated leptin resistance. Some of these changes persist for at least one week after the end of TSR, indicating that even short episodes of sleep disruption can induce prolonged physiological impairments. In contrast, Per1/2 deficient mice show blunted effects of TSR on food intake, leptin levels and adipose transcription. We conclude that the absence of a functional clock in Per1/2 double mutants protects these mice from TSR-induced metabolic reprogramming, suggesting a role of the circadian timing system in regulating the physiological effects

  16. Targeted Disruption of Melanin Biosynthesis Genes in the Human Pathogenic Fungus Lomentospora prolificans and Its Consequences for Pathogen Survival

    Directory of Open Access Journals (Sweden)

    Ayat Al-Laaeiby

    2016-03-01

    Full Text Available The dematiaceous (melanised fungus Lomentospora (Scedosporium prolificans is a life-threatening opportunistic pathogen of immunocompromised humans, resistant to anti-fungal drugs. Melanin has been shown to protect human pathogenic fungi against antifungal drugs, oxidative killing and environmental stresses. To determine the protective role of melanin in L. prolificans to oxidative killing (H2O2, UV radiation and the polyene anti-fungal drug amphotericin B, targeted gene disruption was used to generate mutants of the pathogen lacking the dihydroxynaphthalene (DHN-melanin biosynthetic enzymes polyketide synthase (PKS1, tetrahydroxynapthalene reductase (4HNR and scytalone dehydratase (SCD1. Infectious propagules (spores of the wild-type strain 3.1 were black/brown, whereas spores of the PKS-deficient mutant ΔLppks1::hph were white. Complementation of the albino mutant ΔLppks1::hph restored the black-brown spore pigmentation, while the 4HNR-deficient mutant ΔLp4hnr::hph and SCD-deficient mutant ΔLpscd1::hph both produced orange-yellow spores. The mutants ΔLppks1::hph and ΔLp4hnr::hph showed significant reductions in spore survival following H2O2 treatment, while spores of ΔLpscd1::hph and the ΔLppks1::hph complemented strain ΔLppks1::hph:PKS showed spore survivals similar to strain 3.1. Spores of the mutants ΔLp4hnr::hph and ΔLpscd1::hph and complemented strain ΔLppks1::hph:PKS showed spore survivals similar to 3.1 following exposure to UV radiation, but survival of ΔLppks1::hph spores was significantly reduced compared to the wild-type strain. Strain 3.1 and mutants ΔLp4hnr::hph and ΔLppks1::hph:PKS were resistant to amphotericin B while, paradoxically, the PKS1- and SCD1-deficient mutants showed significant increases in growth in the presence of the antifungal drug. Taken together, these results show that while melanin plays a protective role in the survival of the pathogen to oxidative killing and UV radiation, melanin does not

  17. Targeted Disruption of Melanin Biosynthesis Genes in the Human Pathogenic Fungus Lomentospora prolificans and Its Consequences for Pathogen Survival.

    Science.gov (United States)

    Al-Laaeiby, Ayat; Kershaw, Michael J; Penn, Tina J; Thornton, Christopher R

    2016-03-24

    The dematiaceous (melanised) fungus Lomentospora (Scedosporium) prolificans is a life-threatening opportunistic pathogen of immunocompromised humans, resistant to anti-fungal drugs. Melanin has been shown to protect human pathogenic fungi against antifungal drugs, oxidative killing and environmental stresses. To determine the protective role of melanin in L. prolificans to oxidative killing (H₂O₂), UV radiation and the polyene anti-fungal drug amphotericin B, targeted gene disruption was used to generate mutants of the pathogen lacking the dihydroxynaphthalene (DHN)-melanin biosynthetic enzymes polyketide synthase (PKS1), tetrahydroxynapthalene reductase (4HNR) and scytalone dehydratase (SCD1). Infectious propagules (spores) of the wild-type strain 3.1 were black/brown, whereas spores of the PKS-deficient mutant ΔLppks1::hph were white. Complementation of the albino mutant ΔLppks1::hph restored the black-brown spore pigmentation, while the 4HNR-deficient mutant ΔLp4hnr::hph and SCD-deficient mutant ΔLpscd1::hph both produced orange-yellow spores. The mutants ΔLppks1::hph and ΔLp4hnr::hph showed significant reductions in spore survival following H₂O₂ treatment, while spores of ΔLpscd1::hph and the ΔLppks1::hph complemented strain ΔLppks1::hph:PKS showed spore survivals similar to strain 3.1. Spores of the mutants ΔLp4hnr::hph and ΔLpscd1::hph and complemented strain ΔLppks1::hph:PKS showed spore survivals similar to 3.1 following exposure to UV radiation, but survival of ΔLppks1::hph spores was significantly reduced compared to the wild-type strain. Strain 3.1 and mutants ΔLp4hnr::hph and ΔLppks1::hph:PKS were resistant to amphotericin B while, paradoxically, the PKS1- and SCD1-deficient mutants showed significant increases in growth in the presence of the antifungal drug. Taken together, these results show that while melanin plays a protective role in the survival of the pathogen to oxidative killing and UV radiation, melanin does not

  18. Targeted disruption of the mouse Csrp2 gene encoding the cysteine- and glycine-rich LIM domain protein CRP2 result in subtle alteration of cardiac ultrastructure

    Directory of Open Access Journals (Sweden)

    Stoll Doris

    2008-08-01

    Full Text Available Abstract Background The cysteine and glycine rich protein 2 (CRP2 encoded by the Csrp2 gene is a LIM domain protein expressed in the vascular system, particularly in smooth muscle cells. It exhibits a bimodal subcellular distribution, accumulating at actin-based filaments in the cytosol and in the nucleus. In order to analyze the function of CRP2 in vivo, we disrupted the Csrp2 gene in mice and analysed the resulting phenotype. Results A ~17.3 kbp fragment of the murine Csrp2 gene containing exon 3 through 6 was isolated. Using this construct we confirmed the recently determined chromosomal localization (Chromosome 10, best fit location between markers D10Mit203 proximal and D10Mit150 central. A gene disruption cassette was cloned into exon 4 and a mouse strain lacking functional Csrp2 was generated. Mice lacking CRP2 are viable and fertile and have no obvious deficits in reproduction and survival. However, detailed histological and electron microscopic studies reveal that CRP2-deficient mice have subtle alterations in their cardiac ultrastructure. In these mice, the cardiomyocytes display a slight increase in their thickness, indicating moderate hypertrophy at the cellular level. Although the expression of several intercalated disc-associated proteins such as β-catenin, N-RAP and connexin-43 were not affected in these mice, the distribution of respective proteins was changed within heart tissue. Conclusion We conclude that the lack of CRP2 is associated with alterations in cardiomyocyte thickness and hypertrophy.

  19. Disruption of the Eng18B ENGase gene in the fungal biocontrol agent Trichoderma atroviride affects growth, conidiation and antagonistic ability.

    Directory of Open Access Journals (Sweden)

    Mukesh K Dubey

    Full Text Available The recently identified phylogenetic subgroup B5 of fungal glycoside hydrolase family 18 genes encodes enzymes with mannosyl glycoprotein endo-N-acetyl-β-D-glucosaminidase (ENGase-type activity. Intracellular ENGase activity is associated with the endoplasmic reticulum associated protein degradation pathway (ERAD of misfolded glycoproteins, although the biological relevance in filamentous fungi is not known. Trichoderma atroviride is a mycoparasitic fungus that is used for biological control of plant pathogenic fungi. The present work is a functional study of the T. atroviride B5-group gene Eng18B, with emphasis on its role in fungal growth and antagonism. A homology model of T. atroviride Eng18B structure predicts a typical glycoside hydrolase family 18 (αβ(8 barrel architecture. Gene expression analysis shows that Eng18B is induced in dual cultures with the fungal plant pathogens Botrytis cinerea and Rhizoctonia solani, although a basal expression is observed in all growth conditions tested. Eng18B disruption strains had significantly reduced growth rates but higher conidiation rates compared to the wild-type strain. However, growth rates on abiotic stress media were significantly higher in Eng18B disruption strains compared to the wild-type strain. No difference in spore germination, germ-tube morphology or in hyphal branching was detected. Disruption strains produced less biomass in liquid cultures than the wild-type strain when grown with chitin as the sole carbon source. In addition, we determined that Eng18B is required for the antagonistic ability of T. atroviride against the grey mould fungus B. cinerea in dual cultures and that this reduction in antagonistic ability is partly connected to a secreted factor. The phenotypes were recovered by re-introduction of an intact Eng18B gene fragment in mutant strains. A putative role of Eng18B ENGase activity in the endoplasmic reticulum associated protein degradation pathway of endogenous

  20. Disruption of Bcchs4, Bcchs6 or Bcchs7 chitin synthase genes in Botrytis cinerea and the essential role of class VI chitin synthase (Bcchs6).

    Science.gov (United States)

    Morcx, Serena; Kunz, Caroline; Choquer, Mathias; Assie, Sébastien; Blondet, Eddy; Simond-Côte, Elisabeth; Gajek, Karina; Chapeland-Leclerc, Florence; Expert, Dominique; Soulie, Marie-Christine

    2013-03-01

    Chitin synthases play critical roles in hyphal development and fungal pathogenicity. Previous studies on Botrytis cinerea, a model organism for necrotrophic pathogens, have shown that disruption of Bcchs1 and more particularly Bcchs3a genes have a drastic impact on virulence (Soulié et al., 2003, 2006). In this work, we investigate the role of other CHS including BcCHS4, BcCHS6 and BcCHS7 during the life cycle of B. cinerea. Single deletions of corresponding genes were carried out. Phenotypic analysis indicates that: (i) BcCHS4 enzyme is not essential for development and pathogenicity of the fungus; (ii) BcCHS7 is required for pathogenicity in a host dependant manner. For Bcchs6 gene disruption, we obtained only heterokaryotic strains. Indeed, sexual or asexual purification assays were unsuccessful. We concluded that class VI chitin synthase could be essential for B. cinerea and therefore BcCHS6 represents a valuable antifungal target. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. ADHD and Disruptive behavior scores – associations with MAO-A and 5-HTT genes and with platelet MAO-B activity in adolescents

    Directory of Open Access Journals (Sweden)

    Larsson Jan-Olov

    2008-04-01

    Full Text Available Abstract Background Pharmacological and genetic studies suggest the importance of the dopaminergic, serotonergic, and noradrenergic systems in the pathogenesis of Attention Deficit Hyperactivity Disorder (ADHD and Disruptive Behavior Disorder (DBD. We have, in a population-based sample, studied associations between dimensions of the ADHD/DBD phenotype and Monoamine Oxidase B (MAO-B activity in platelets and polymorphisms in two serotonergic genes: the Monoamine Oxidase A Variable Number of Tandem Repeats (MAO-A VNTR and the 5-Hydroxytryptamine Transporter gene-Linked Polymorphic Region (5-HTT LPR. Methods A population-based sample of twins, with an average age of 16 years, was assessed for ADHD/DBD with a clinical interview; Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version (K-SADS-PL. Blood was drawn from 247 subjects and analyzed for platelet MAO-B activity and polymorphisms in the MAO-A and 5-HTT genes. Results We found an association in girls between low platelet MAO-B activity and symptoms of Oppositional Defiant Disorder (ODD. In girls, there was also an association between the heterozygote long/short 5-HTT LPR genotype and symptoms of conduct disorder. Furthermore the heterozygote 5-HTT LPR genotype in boys was found to be associated with symptoms of Conduct Disorder (CD. In boys, hemizygosity for the short MAO-A VNTR allele was associated with disruptive behavior. Conclusion Our study suggests that the serotonin system, in addition to the dopamine system, should be further investigated when studying genetic influences on the development of Disruptive Behavior Disorders.

  2. Disruption of the petal identity gene APETALA3-3 is highly correlated with loss of petals within the buttercup family (Ranunculaceae).

    Science.gov (United States)

    Zhang, Rui; Guo, Chunce; Zhang, Wengen; Wang, Peipei; Li, Lin; Duan, Xiaoshan; Du, Qinggao; Zhao, Liang; Shan, Hongyan; Hodges, Scott A; Kramer, Elena M; Ren, Yi; Kong, Hongzhi

    2013-03-26

    Absence of petals, or being apetalous, is usually one of the most important features that characterizes a group of flowering plants at high taxonomic ranks (i.e., family and above). The apetalous condition, however, appears to be the result of parallel or convergent evolution with unknown genetic causes. Here we show that within the buttercup family (Ranunculaceae), apetalous genera in at least seven different lineages were all derived from petalous ancestors, indicative of parallel petal losses. We also show that independent petal losses within this family were strongly associated with decreased or eliminated expression of a single floral organ identity gene, APETALA3-3 (AP3-3), apparently owing to species-specific molecular lesions. In an apetalous mutant of Nigella, insertion of a transposable element into the second intron has led to silencing of the gene and transformation of petals into sepals. In several naturally occurring apetalous genera, such as Thalictrum, Beesia, and Enemion, the gene has either been lost altogether or disrupted by deletions in coding or regulatory regions. In Clematis, a large genus in which petalous species evolved secondarily from apetalous ones, the gene exhibits hallmarks of a pseudogene. These results suggest that, as a petal identity gene, AP3-3 has been silenced or down-regulated by different mechanisms in different evolutionary lineages. This also suggests that petal identity did not evolve many times independently across the Ranunculaceae but was lost in numerous instances. The genetic mechanisms underlying the independent petal losses, however, may be complex, with disruption of AP3-3 being either cause or effect.

  3. Investigating Disruption

    DEFF Research Database (Denmark)

    Lundgaard, Stine Schmieg; Rosenstand, Claus Andreas Foss

    This book shares knowledge collected from 2015 and onward within the Consortium for Digital Disruption anchored at Aalborg University (www.dd.aau.dk). Evidenced by this publication, the field of disruptive innovation research has gone through several stages of operationalizing the theory. In recent...... years, researchers are increasingly looking back towards the origins of the theory in attempts to cure it from its most obvious flaws. This is especially true for the use of the theory in making predictions about future disruptions. In order to continue to develop a valuable theory of disruption, we...... find it useful to first review what the theory of disruptive innovation initially was, how it has developed, and where we are now. A cross section of disruptive innovation literature has been reviewed in order to form a general foundation from which we might better understand the changing world...

  4. Transplacental exposure to inorganic arsenic at a hepatocarcinogenic dose induces fetal gene expression changes in mice indicative of aberrant estrogen signaling and disrupted steroid metabolism

    International Nuclear Information System (INIS)

    Liu Jie; Xie Yaxiong; Cooper, Ryan; Ducharme, Danica M.K.; Tennant, Raymond; Diwan, Bhalchandra A.; Waalkes, Michael P.

    2007-01-01

    Exposure to inorganic arsenic in utero in C3H mice produces hepatocellular carcinoma in male offspring when they reach adulthood. To help define the molecular events associated with the fetal onset of arsenic hepatocarcinogenesis, pregnant C3H mice were given drinking water containing 0 (control) or 85 ppm arsenic from day 8 to 18 of gestation. At the end of the arsenic exposure period, male fetal livers were removed and RNA isolated for microarray analysis using 22K oligo chips. Arsenic exposure in utero produced significant (p < 0.001) alterations in expression of 187 genes, with approximately 25% of aberrantly expressed genes related to either estrogen signaling or steroid metabolism. Real-time RT-PCR on selected genes confirmed these changes. Various genes controlled by estrogen, including X-inactive-specific transcript, anterior gradient-2, trefoil factor-1, CRP-ductin, ghrelin, and small proline-rich protein-2A, were dramatically over-expressed. Estrogen-regulated genes including cytokeratin 1-19 and Cyp2a4 were over-expressed, although Cyp3a25 was suppressed. Several genes involved with steroid metabolism also showed remarkable expression changes, including increased expression of 17β-hydroxysteroid dehydrogenase-7 (HSD17β7; involved in estradiol production) and decreased expression of HSD17β5 (involved in testosterone production). The expression of key genes important in methionine metabolism, such as methionine adenosyltransferase-1a, betaine-homocysteine methyltransferase and thioether S-methyltransferase, were suppressed. Thus, exposure of mouse fetus to inorganic arsenic during a critical period in development significantly alters the expression of various genes encoding estrogen signaling and steroid or methionine metabolism. These alterations could disrupt genetic programming at the very early life stage, which could impact tumor formation much later in adulthood

  5. KANSL1 gene disruption associated with the full clinical spectrum of 17q21.31 microdeletion syndrome

    OpenAIRE

    Moreno-Igoa, María; Hernández-Charro, Blanca; Bengoa-Alonso, Amaya; Pérez-Juana-del-Casal, Aranzazu; Romero-Ibarra, Carlos; Nieva-Echebarria, Beatriz; Ramos-Arroyo, María Antonia

    2015-01-01

    Background Chromosome 17q21.31 microdeletion syndrome is a multisystem genomic disorder caused by a recurrent 600-kb-long deletion, or haploinsufficiency of the chromatin modifier gene KANSL1, which maps to that region. Patients with KANSL1 intragenic mutations have been reported to display the major clinical features of 17q21.31 microdeletion syndrome. However, they did not exhibit the full clinical spectrum of this disorder, which might indicate that an additional gene or genes, located in ...

  6. Disruption model

    International Nuclear Information System (INIS)

    Murray, J.G.; Bronner, G.

    1982-07-01

    Calculations of disruption time and energy dissipation have been obtained by simulating the plasma as an electrical conducting loop that varies in resistivity, current density, major radius. The calculations provide results which are in good agreement with experimental observations. It is believed that this approach allows engineering designs for disruptions to be completed in large tokamaks such as INTOR or FED

  7. Shift work or food intake during the rest phase promotes metabolic disruption and desynchrony of liver genes in male rats.

    Science.gov (United States)

    Salgado-Delgado, Roberto C; Saderi, Nadia; Basualdo, María del Carmen; Guerrero-Vargas, Natali N; Escobar, Carolina; Buijs, Ruud M

    2013-01-01

    In the liver, clock genes are proposed to drive metabolic rhythms. These gene rhythms are driven by the suprachiasmatic nucleus (SCN) mainly by food intake and via autonomic and hormonal pathways. Forced activity during the normal rest phase, induces also food intake, thus neglecting the signals of the SCN, leading to conflicting time signals to target tissues of the SCN. The present study explored in a rodent model of night-work the influence of food during the normal sleep period on the synchrony of gene expression between clock genes and metabolic genes in the liver. Male Wistar rats were exposed to forced activity for 8 h either during the rest phase (day) or during the active phase (night) by using a slow rotating wheel. In this shift work model food intake shifts spontaneously to the forced activity period, therefore the influence of food alone without induced activity was tested in other groups of animals that were fed ad libitum, or fed during their rest or active phase. Rats forced to be active and/or eating during their rest phase, inverted their daily peak of Per1, Bmal1 and Clock and lost the rhythm of Per2 in the liver, moreover NAMPT and metabolic genes such as Pparα lost their rhythm and thus their synchrony with clock genes. We conclude that shift work or food intake in the rest phase leads to desynchronization within the liver, characterized by misaligned temporal patterns of clock genes and metabolic genes. This may be the cause of the development of the metabolic syndrome and obesity in individuals engaged in shift work.

  8. Practical method for targeted disruption of cilia-related genes by using CRISPR/Cas9-mediated, homology-independent knock-in system.

    Science.gov (United States)

    Katoh, Yohei; Michisaka, Saki; Nozaki, Shohei; Funabashi, Teruki; Hirano, Tomoaki; Takei, Ryota; Nakayama, Kazuhisa

    2017-04-01

    The CRISPR/Cas9 system has revolutionized genome editing in virtually all organisms. Although the CRISPR/Cas9 system enables the targeted cleavage of genomic DNA, its use for gene knock-in remains challenging because levels of homologous recombination activity vary among various cells. In contrast, the efficiency of homology-independent DNA repair is relatively high in most cell types. Therefore the use of a homology-independent repair mechanism is a possible alternative for efficient genome editing. Here we constructed a donor knock-in vector optimized for the CRISPR/Cas9 system and developed a practical system that enables efficient disruption of target genes by exploiting homology-independent repair. Using this practical knock-in system, we successfully disrupted genes encoding proteins involved in ciliary protein trafficking, including IFT88 and IFT20, in hTERT-RPE1 cells, which have low homologous recombination activity. The most critical concern using the CRISPR/Cas9 system is off-target cleavage. To reduce the off-target cleavage frequency and increase the versatility of our knock-in system, we constructed a universal donor vector and an expression vector containing Cas9 with enhanced specificity and tandem sgRNA expression cassettes. We demonstrated that the second version of our system has improved usability. © 2017 Katoh et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  9. Disrupted Disclosure

    DEFF Research Database (Denmark)

    Krause Hansen, Hans; Uldam, Julie

    appearances become challenged through disruptive disclosures in mediaenvironments characterized by multiple levels of visibility, with companies both observing andbeing observed by civil society groups that criticize them; (c) why and how the mobilization aroundtransparency and ensuing practices...

  10. Family Disruptions

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Family Life Medical Home Family Dynamics Adoption & Foster Care ... Life Listen Español Text Size Email Print Share Family Disruptions Page Content Article Body No matter how ...

  11. Exposure of maternal mice to cis-bifenthrin enantioselectively disrupts the transcription of genes related to testosterone synthesis in male offspring.

    Science.gov (United States)

    Jin, Yuanxiang; Wang, Jiangcong; Sun, Xueqing; Ye, Yang; Xu, Minjie; Wang, Jianai; Chen, Shaoping; Fu, Zhengwei

    2013-12-01

    The commercial bifenthrin (BF) contains two cis isomers. In the present study, a dose of 15mg/kg of 1R-cis-BF or 1S-cis-BF was orally administered for 3 weeks to female mice before or during pregnancy. Then, the expression of steroidogenesis related genes which were considered as effective biomarkers of endocrine disruption were analyzed in the male offspring. Maternal exposure to 1S-cis-BF during pregnancy significantly reduced the mRNA levels of peripheral benzodiazepine receptor (PBR) and steroidogenic acute regulatory protein (StAR) in the testes of 3- or 6-week old male offspring. In addition, a significant decrease of cytochrome P450 17α-hydroxysteroid dehydrogenase (P450-17α) was also observed in the testes of 6-week old male offspring when dams were treated with 1S-cis-BF during pregnancy but not before pregnancy. Moreover, the scavenger receptor class B type 1 (SRB1) and cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc) decreased significantly in the testes of 6-week old male offspring when dams were treated with 1S-cis-BF during and before pregnancy. Thus, oral administration of the maternal mice to cis-BF for 3 weeks, particularly during pregnancy, resulted in endocrine disruption in the male offspring, with the 1S-cis-BF causing more significant alterations than the 1R-cis-BF form. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Cytotoxic effects induced by interferon-ω gene lipofection through ROS generation and mitochondrial membrane potential disruption in feline mammary carcinoma cells.

    Science.gov (United States)

    Villaverde, Marcela Solange; Targovnik, Alexandra Marisa; Miranda, María Victoria; Finocchiaro, Liliana María Elena; Glikin, Gerardo Claudio

    2016-08-01

    Progress in comparative oncology promises advances in clinical cancer treatments for both companion animals and humans. In this context, feline mammary carcinoma (FMC) cells have been proposed as a suitable model to study human breast cancer. Based on our previous data about the advantages of using type I interferon gene therapy over the respective recombinant DNA derived protein, the present work explored the effects of feline interferon-ω gene (fIFNω) transfer on FMC cells. Three different cell variants derived from a single spontaneous highly aggressive FMC tumor were successfully established and characterized. Lipofection of the fIFNω gene displayed a significant cytotoxic effect on the three cell variants. The extent of the response was proportional to ROS generation, mitochondrial membrane potential disruption and calcium uptake. Moreover, a lower sensitivity to the treatment correlated with a higher malignant phenotype. Our results suggest that fIFNω lipofection could offer an alternative approach in veterinary oncology with equal or superior outcome and with less adverse effects than recombinant fIFNω therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. A mammalian model for Laron syndrome produced by targeted disruption of the mouse growth hormone receptor/binding protein gene (the Laron mouse)

    Science.gov (United States)

    Zhou, Yihua; Xu, Bixiong C.; Maheshwari, Hiralal G.; He, Li; Reed, Michael; Lozykowski, Maria; Okada, Shigeru; Cataldo, Lori; Coschigamo, Karen; Wagner, Thomas E.; Baumann, Gerhard; Kopchick, John J.

    1997-01-01

    Laron syndrome [growth hormone (GH) insensitivity syndrome] is a hereditary dwarfism resulting from defects in the GH receptor (GHR) gene. GHR deficiency has not been reported in mammals other than humans. Many aspects of GHR dysfunction remain unknown because of ethical and practical limitations in studying humans. To create a mammalian model for this disease, we generated mice bearing a disrupted GHR/binding protein (GHR/BP) gene through a homologous gene targeting approach. Homozygous GHR/BP knockout mice showed severe postnatal growth retardation, proportionate dwarfism, absence of the GHR and GH binding protein, greatly decreased serum insulin-like growth factor I and elevated serum GH concentrations. These characteristics represent the phenotype typical of individuals with Laron syndrome. Animals heterozygous for the GHR/BP defect show only minimal growth impairment but have an intermediate biochemical phenotype, with decreased GHR and GH binding protein expression and slightly diminished insulin-like growth factor I levels. These findings indicate that the GHR/BP-deficient mouse (Laron mouse) is a suitable model for human Laron syndrome that will prove useful for the elucidation of many aspects of GHR/BP function that cannot be obtained in humans. PMID:9371826

  14. Evidence for association between Disrupted-in-schizophrenia 1 (DISC1 gene polymorphisms and autism in Chinese Han population: a family-based association study

    Directory of Open Access Journals (Sweden)

    Ruan Yan

    2011-05-01

    Full Text Available Abstract Background Disrupted-in-Schizophrenia 1 (DISC1 gene is one of the most promising candidate genes for major mental disorders. In a previous study, a Finnish group demonstrated that DISC1 polymorphisms were associated with autism and Asperger syndrome. However, the results were not replicated in Korean population. To determine whether DISC1 is associated with autism in Chinese Han population, we performed a family-based association study between DISC1 polymorphisms and autism. Methods We genotyped seven tag single nucleotide polymorphisms (SNPs in DISC1, spanning 338 kb, in 367 autism trios (singleton and their biological parents including 1,101 individuals. Single SNP association and haplotype association analysis were performed using the family-based association test (FBAT and Haploview software. Results We found three SNPs showed significant associations with autism (rs4366301: G > C, Z = 2.872, p = 0.004; rs11585959: T > C, Z = 2.199, p = 0.028; rs6668845: A > G, Z = 2.326, p = 0.02. After the Bonferroni correction, SNP rs4366301, which located in the first intron of DISC1, remained significant. When haplotype were constructed with two-markers, three haplotypes displayed significant association with autism. These results were still significant after using the permutation method to obtain empirical p values. Conclusions Our study provided evidence that the DISC1 may be the susceptibility gene of autism. It suggested DISC1 might play a role in the pathogenesis of autism.

  15. A mammalian model for Laron syndrome produced by targeted disruption of the mouse growth hormone receptor/binding protein gene (the Laron mouse).

    Science.gov (United States)

    Zhou, Y; Xu, B C; Maheshwari, H G; He, L; Reed, M; Lozykowski, M; Okada, S; Cataldo, L; Coschigamo, K; Wagner, T E; Baumann, G; Kopchick, J J

    1997-11-25

    Laron syndrome [growth hormone (GH) insensitivity syndrome] is a hereditary dwarfism resulting from defects in the GH receptor (GHR) gene. GHR deficiency has not been reported in mammals other than humans. Many aspects of GHR dysfunction remain unknown because of ethical and practical limitations in studying humans. To create a mammalian model for this disease, we generated mice bearing a disrupted GHR/binding protein (GHR/BP) gene through a homologous gene targeting approach. Homozygous GHR/BP knockout mice showed severe postnatal growth retardation, proportionate dwarfism, absence of the GHR and GH binding protein, greatly decreased serum insulin-like growth factor I and elevated serum GH concentrations. These characteristics represent the phenotype typical of individuals with Laron syndrome. Animals heterozygous for the GHR/BP defect show only minimal growth impairment but have an intermediate biochemical phenotype, with decreased GHR and GH binding protein expression and slightly diminished insulin-like growth factor I levels. These findings indicate that the GHR/BP-deficient mouse (Laron mouse) is a suitable model for human Laron syndrome that will prove useful for the elucidation of many aspects of GHR/BP function that cannot be obtained in humans.

  16. Digital Disruption

    DEFF Research Database (Denmark)

    Rosenstand, Claus Andreas Foss

    det digitale domæne ud over det niveau, der kendetegner den nuværende debat, så præsenteres der ny viden om digital disruption. Som noget nyt udlægges Clayton Christens teori om disruptiv innovation med et særligt fokus på små organisationers mulighed for eksponentiel vækst. Specielt udfoldes...... forholdet mellem disruption og den stadig accelererende digitale udvikling i konturerne til ny teoridannelse om digital disruption. Bogens undertitel ”faretruende og fascinerende forandringer” peger på, at der er behov for en nuanceret debat om digital disruption i modsætning til den tone, der er slået an i...... videre kalder et ”disruption-råd”. Faktisk er rådet skrevet ind i 2016 regeringsgrundlaget for VLK-regeringen. Disruption af organisationer er ikke et nyt fænomen; men hastigheden, hvormed det sker, er stadig accelererende. Årsagen er den globale mega-trend: Digitalisering. Og derfor er specielt digital...

  17. Efficient disruption and replacement of an effector gene in the oomycete Phytophthora sojae using CRISPR/Cas9.

    Science.gov (United States)

    Fang, Yufeng; Tyler, Brett M

    2016-01-01

    Phytophthora sojae is an oomycete pathogen of soybean. As a result of its economic importance, P. sojae has become a model for the study of oomycete genetics, physiology and pathology. The lack of efficient techniques for targeted mutagenesis and gene replacement have long hampered genetic studies of pathogenicity in Phytophthora species. Here, we describe a CRISPR/Cas9 system enabling rapid and efficient genome editing in P. sojae. Using the RXLR effector gene Avr4/6 as a target, we observed that, in the absence of a homologous template, the repair of Cas9-induced DNA double-strand breaks (DSBs) in P. sojae was mediated by non-homologous end-joining (NHEJ), primarily resulting in short indels. Most mutants were homozygous, presumably as a result of gene conversion triggered by Cas9-mediated cleavage of non-mutant alleles. When donor DNA was present, homology-directed repair (HDR) was observed, which resulted in the replacement of Avr4/6 with the NPT II gene. By testing the specific virulence of several NHEJ mutants and HDR-mediated gene replacements in soybean, we have validated the contribution of Avr4/6 to recognition by soybean R gene loci, Rps4 and Rps6, but also uncovered additional contributions to resistance by these two loci. Our results establish a powerful tool for the study of functional genomics in Phytophthora, which provides new avenues for better control of this pathogen. © 2015 THE AUTHORS. MOLECULAR PLANT PATHOLOGY PUBLISHED BY JOHN WILEY & SONS LTD AND BSPP.

  18. Disruption of prefoldin-2 protein synthesis in root-knot nematodes via host-mediated gene silencing efficiently reduces nematode numbers and thus protects plants.

    Science.gov (United States)

    Ajjappala, Hemavathi; Chung, Ha Young; Sim, Joon-Soo; Choi, Inchan; Hahn, Bum-Soo

    2015-03-01

    The aim of this study is to demonstrate the feasibility of down-regulating endogeneous prefoldin-2 root-knot nematode transcripts by expressing dsRNA with sequence identity to the nematode gene in tobacco roots under the influence of strong Arabidopsis ubiquitin (UBQ1) promoter. Root-knot nematodes (RKNs) are sedentary endoparasites infecting a wide range of plant species. They parasitise the root system, thereby disrupting water and nutrient uptake and causing major reductions in crop yields. The most reliable means of controlling RKNs is via the use of soil fumigants such as methyl bromide. With the emergence of RNA interference (RNAi) technology, which permits host-mediated nematode gene silencing, a new strategy to control plant pathogens has become available. In the present study, we investigated host-induced RNAi gene silencing of prefoldin-2 in transgenic Nicotiana benthamiana. Reductions in prefoldin-2 mRNA transcript levels were observed when nematodes were soaked in a dsRNA solution in vitro. Furthermore, nematode reproduction was suppressed in RNAi transgenic lines, as evident by reductions in the numbers of root knots (by 34-60 % in independent RNAi lines) and egg masses (by 33-58 %). Endogenous expression of prefoldin-2, analysed via real-time polymerase chain reaction and Western blotting, revealed that the gene was strongly expressed in the pre-parasitic J2 stage. Our observations demonstrate the relevance and potential importance of targeting the prefoldin gene during the nematode life cycle. The work also suggests that further improvements in silencing efficiency in economically important crops can be accomplished using RNAi directed against plant-parasitic nematodes.

  19. Mutation of the mouse Syce1 gene disrupts synapsis and suggests a link between synaptonemal complex structural components and DNA repair.

    Directory of Open Access Journals (Sweden)

    Ewelina Bolcun-Filas

    2009-02-01

    Full Text Available In mammals, the synaptonemal complex is a structure required to complete crossover recombination. Although suggested by cytological work, in vivo links between the structural proteins of the synaptonemal complex and the proteins of the recombination process have not previously been made. The central element of the synaptonemal complex is traversed by DNA at sites of recombination and presents a logical place to look for interactions between these components. There are four known central element proteins, three of which have previously been mutated. Here, we complete the set by creating a null mutation in the Syce1 gene in mouse. The resulting disruption of synapsis in these animals has allowed us to demonstrate a biochemical interaction between the structural protein SYCE2 and the repair protein RAD51. In normal meiosis, this interaction may be responsible for promoting homologous synapsis from sites of recombination.

  20. Isolation of Penicillium nalgiovense strains impaired in penicillin production by disruption of the pcbAB gene and application as starters on cured meat products.

    Science.gov (United States)

    Laich, Federico; Fierro, Francisco; Martin, Juan F

    2003-06-01

    The presence of some fungi on a variety of food products, like cheeses or cured meat products, is beneficial for the ripening of the product and for the development of specific flavour features. The utilization of these fungi as starters, which are inoculated normally as asexual spores on the food products at the beginning of the ripening process, is becoming a usual procedure in the food industry. The starter culture also prevents undesirable fungi or bacteria from growing on the product. Penicillium nalgiovense is the most frequently used starter for cured and fermented meat products, but the fact that this fungus can secrete penicillin to the meat product makes it important to get strains unable to synthesize this antibiotic. In this work we report that P. nalgiovense strains impaired in penicillin production can be obtained by disruption of the pcbAB gene (the first gene of the penicillin biosynthetic pathway). When applied as starter on cecina (a salted, smoke-cured beef meat product from the region of León, Spain), the pcbAB-disrupted strain showed no differences with respect to the parental penicillin-producing strain in its ability to colonize the meat pieces and to control their normal mycoflora. Both strains exerted a similar control on the presence of bacteria in cecina. A similar proportion of penicillin-sensitive and penicillin-resistant bacteria were isolated from pieces inoculated with the penicillin-producing or the non-producing P. nalgiovense strains. The decrease of the bacterial population on the surface of cecina seems to be due to the higher competition for nutrients as a consequence of the inoculation and development of the P. nalgiovense mycelium and not due to the production of penicillin by this fungus. Penicillin production was less affected than growth in a solid medium with high NaCl concentrations; this suggests that the high salt concentration present in cecina is not a limiting factor for penicillin production by P. nalgiovense.

  1. Ovotoxicants 4-vinylcyclohexene 1,2-monoepoxide and 4-vinylcyclohexene diepoxide disrupt redox status and modify different electrophile sensitive target enzymes and genes in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Amos O. Abolaji

    2015-08-01

    Full Text Available The compounds 4-vinylcyclohexene 1,2-monoepoxide (VCM and 4-Vinylcyclohexene diepoxide (VCD are the two downstream metabolites of 4-vinylcyclohexene (VCH, an ovotoxic agent in mammals. In addition, VCM and VCD may be found as by-products of VCH oxidation in the environment. Recently, we reported the involvement of oxidative stress in the toxicity of VCH in Drosophila melanogaster. However, it was not possible to determine the individual contributions of VCM and VCD in VCH toxicity. Hence, we investigated the toxicity of VCM and VCD (10–1000 µM in flies after 5 days of exposure via the diet. Our results indicated impairments in climbing behaviour and disruptions in antioxidant balance and redox status evidenced by an increase in DCFH oxidation, decreases in total thiol content and glutathione-S-transferase (GST activity in the flies exposed to VCM and VCD (p<0.05. These effects were accompanied by disruptions in the transcription of the genes encoding the proteins superoxide dismutase (SOD1, kelch-like erythroid-derived cap-n-collar (CNC homology (ECH-associated protein 1 (Keap-1, mitogen activated protein kinase 2 (MAPK-2, catalase, Cyp18a1, JAFRAC 1 (thioredoxin peroxidase 1 and thioredoxin reductase 1 (TrxR-1 (p<0.05. VCM and VCD inhibited acetylcholinesterase (AChE and delta aminolevulinic acid dehydratase (δ-ALA D activities in the flies (p<0.05. Indeed, here, we demonstrated that different target enzymes and genes were modified by the electrophiles VCM and VCD in the flies. Thus, D. melanogaster has provided further lessons on the toxicity of VCM and VCD which suggest that the reported toxicity of VCH may be mediated by its transformation to VCM and VCD.

  2. Disruption of plant carotenoid biosynthesis through virus-induced gene silencing affects oviposition behaviour of the butterfly Pieris rapae

    NARCIS (Netherlands)

    Zheng, S.J.; Snoeren, T.A.L.; Hogewoning, S.W.; Loon, van J.J.A.; Dicke, M.

    2010-01-01

    Optical plant characteristics are important cues to plant-feeding insects. In this article, we demonstrate for the first time that silencing the phytoene desaturase (PDS) gene, encoding a key enzyme in plant carotenoid biosynthesis, affects insect oviposition site selection behaviour. Virus-induced

  3. Nonfunctionality of Aspergillus sojae aflR in a strain of Aspergillus parasiticus with a disrupted aflR gene.

    Science.gov (United States)

    Takahashi, Tadashi; Chang, Perng-Kuang; Matsushima, Kenichiro; Yu, Jiujiang; Abe, Keietsu; Bhatnagar, Deepak; Cleveland, Thomas E; Koyama, Yasuji

    2002-08-01

    Aspergillus sojae belongs to the Aspergillus section Flavi but does not produce aflatoxins. The functionality of the A. sojae aflR gene (aflRs) was examined by transforming it into an DeltaaflR strain of A. parasiticus, derived from a nitrate-nonutilizing, versicolorin A (VERA)-accumulating strain. The A. parasiticus aflR gene (aflRp) transformants produced VERA, but the aflRs transformants did not. Even when aflRs was placed under the control of the amylase gene (amyB) promoter of Aspergillus oryzae, the amy(p)::aflRs transformants did not produce VERA. A chimeric construct containing the aflRs promoter plus the aflRs N- and aflRp C-terminal coding regions could restore VERA production, but a construct containing the aflRp promoter plus the aflRp N- and aflRs C-terminal coding regions could not. These results show that the A. sojae aflR promoter is functional in A. parasiticus and that the HAHA motif does not affect the function of the resulting hybrid AflR. We conclude that the lack of aflatoxin production by A. sojae can be attributed, at least partially, to the premature termination defect in aflRs, which deletes the C-terminal transcription activation domain that is critical for the expression of aflatoxin biosynthetic genes.

  4. Silencing abnormal wing disc gene of the Asian citrus psyllid, Diaphorina citri disrupts adult wing development and increases nymph mortality.

    Directory of Open Access Journals (Sweden)

    Ibrahim El-Shesheny

    Full Text Available Huanglongbing (HLB causes considerable economic losses to citrus industries worldwide. Its management depends on controlling of the Asian citrus Psyllid (ACP, the vector of the bacterium, Candidatus Liberibacter asiaticus (CLas, the causal agent of HLB. Silencing genes by RNA interference (RNAi is a promising tool to explore gene functions as well as control pests. In the current study, abnormal wing disc (awd gene associated with wing development in insects is used to interfere with the flight of psyllids. Our study showed that transcription of awd is development-dependent and the highest level was found in the last instar (5(th of the nymphal stage. Micro-application (topical application of dsRNA to 5(th instar of nymphs caused significant nymphal mortality and adult wing-malformation. These adverse effects in ACP were positively correlated with the amounts of dsRNA used. A qRT-PCR analysis confirmed the dsRNA-mediated transcriptional down-regulation of the awd gene. Significant down-regulation was required to induce a wing-malformed phenotype. No effect was found when dsRNA-gfp was used, indicating the specific effect of dsRNA-awd. Our findings suggest a role for awd in ACP wing development and metamorphosis. awd could serve as a potential target for insect management either via direct application of dsRNA or by producing transgenic plants expressing dsRNA-awd. These strategies will help to mitigate HLB by controlling ACP.

  5. Sexually dimorphic gene regulation in brain as a target for endocrine disrupters: Developmental exposure of rats to 4-methylbenzylidene camphor

    International Nuclear Information System (INIS)

    Maerkel, Kirsten; Durrer, Stefan; Henseler, Manuel; Schlumpf, Margret; Lichtensteiger, Walter

    2007-01-01

    The developing neuroendocrine brain represents a potential target for endocrine active chemicals. The UV filter 4-methylbenzylidene camphor (4-MBC) exhibits estrogenic activity, but also interferes with the thyroid axis. We investigated effects of pre- and postnatal exposure to 4-MBC in the same rat offspring at brain and reproductive organ levels. 4-MBC (7, 24, 47 mg/kg/day) was administered in chow to the parent generation before mating, during gestation and lactation, and to the offspring until adulthood. mRNA of estrogen target genes involved in control of sexual behavior and gonadal functions was measured by real-time RT-PCR in ventromedial hypothalamic nucleus (VMH) and medial preoptic area (MPO) of adult offspring. 4-MBC exposure affected mRNA levels of ER alpha, progesterone receptor (PR), preproenkephalin (PPE) and insulin-like growth factor-I (IGF-I) in a sex- and region-specific manner. In order to assess possible changes in sensitivity of target genes to estrogens, offspring were gonadectomized on day 70, injected with estradiol (E2, 10 or 50 μg/kg s.c.) or vehicle on day 84, and sacrificed 6 h later. The acute induction of PR mRNA, and repression (at 6 h) of PPE mRNA by E2 was enhanced by 4-MBC in male and female VMH and female MPO, whereas male MPO exhibited reduced responsiveness of both genes. Steroid receptor coactivator SRC-1 mRNA levels were increased in female VMH and MPO. The data indicate profound sex- and region-specific alterations in the regulation of estrogen target genes at brain level. Effect patterns in baseline and E2-induced gene expression differ from those in uterus and prostate

  6. RNAi of the circadian clock gene period disrupts the circadian rhythm but not the circatidal rhythm in the mangrove cricket

    OpenAIRE

    Takekata, Hiroki; Matsuura, Yu; Goto, Shin G.; Satoh, Aya; Numata, Hideharu

    2012-01-01

    The clock mechanism for circatidal rhythm has long been controversial, and its molecular basis is completely unknown. The mangrove cricket, Apteronemobius asahinai, shows two rhythms simultaneously in its locomotor activity: a circatidal rhythm producing active and inactive phases as well as a circadian rhythm modifying the activity intensity of circatidal active phases. The role of the clock gene period (per), one of the key components of the circadian clock in insects, was investigated in t...

  7. Targeted gene disruption by use of transcription activator-like effector nuclease (TALEN) in the water flea Daphnia pulex.

    Science.gov (United States)

    Hiruta, Chizue; Ogino, Yukiko; Sakuma, Tetsushi; Toyota, Kenji; Miyagawa, Shinichi; Yamamoto, Takashi; Iguchi, Taisen

    2014-11-18

    The cosmopolitan microcrustacean Daphnia pulex provides a model system for both human health research and monitoring ecosystem integrity. It is the first crustacean to have its complete genome sequenced, an unprecedented ca. 36% of which has no known homologs with any other species. Moreover, D. pulex is ideally suited for experimental manipulation because of its short reproductive cycle, large numbers of offspring, synchronization of oocyte maturation, and other life history characteristics. However, existing gene manipulation techniques are insufficient to accurately define gene functions. Although our previous investigations developed an RNA interference (RNAi) system in D. pulex, the possible time period of functional analysis was limited because the effectiveness of RNAi is transient. Thus, in this study, we developed a genome editing system for D. pulex by first microinjecting transcription activator-like effector nuclease (TALEN) mRNAs into early embryos and then evaluating TALEN activity and mutation phenotypes. We assembled a TALEN construct specific to the Distal-less gene (Dll), which is a homeobox transcription factor essential for distal limb development in invertebrates and vertebrates, and evaluated its activity in vitro by single-strand annealing assay. Then, we injected TALEN mRNAs into eggs within 1 hour post-ovulation. Injected embryos presented with defects in the second antenna and altered appendage development, and indel mutations were detected in Dll loci, indicating that this technique successfully knocked out the target gene. We succeeded, for the first time in D. pulex, in targeted mutagenesis by use of Platinum TALENs. This genome editing technique makes it possible to conduct reverse genetic analysis in D. pulex, making this species an even more appropriate model organism for environmental, evolutionary, and developmental genomics.

  8. Politisk disruption

    DEFF Research Database (Denmark)

    Tække, Jesper

    2018-01-01

    Dette blogindlæg giver en kort analyse af hvordan de sociale medier ved at give en ny tid har åbnet for den disruption af de politiske processer som især Trump stå som et eksempel på.......Dette blogindlæg giver en kort analyse af hvordan de sociale medier ved at give en ny tid har åbnet for den disruption af de politiske processer som især Trump stå som et eksempel på....

  9. Disrupting Business

    DEFF Research Database (Denmark)

    Cox, Geoff; Bazzichelli, Tatiana

    Disruptive Business explores some of the interconnections between art, activism and the business concept of disruptive innovation. With a backdrop of the crisis of financial capitalism, austerity cuts in the cultural sphere, the idea is to focus on potential art strategies in relation to a broken...... economy. In a perverse way, we ask whether this presents new opportunities for cultural producers to achieve more autonomy over their production process. If it is indeed possible, or desirable, what alternative business models emerge? The book is concerned broadly with business as material for reinvention...

  10. Nance-Horan syndrome in females due to a balanced X;1 translocation that disrupts the NHS gene: Familial case report and review of the literature.

    Science.gov (United States)

    Gómez-Laguna, Laura; Martínez-Herrera, Alejandro; Reyes-de la Rosa, Alejandra Del Pilar; García-Delgado, Constanza; Nieto-Martínez, Karem; Fernández-Ramírez, Fernando; Valderrama-Atayupanqui, Tania Yanet; Morales-Jiménez, Ariadna Berenice; Villa-Morales, Judith; Kofman, Susana; Cervantes, Alicia; Morán-Barroso, Verónica Fabiola

    2018-01-01

    The Nance-Horan syndrome is an X-linked disorder characterized by congenital cataract, facial features, microcornea, microphthalmia, and dental anomalies; most of the cases are due to NHS gene mutations on Xp22.13. Heterozygous carrier females generally present less severe features, and up to 30% of the affected males have intellectual disability. We describe two patients, mother and daughter, manifesting Nance-Horan syndrome. The cytogenetic and molecular analyses demonstrated a 46,X,t(X;1)(p22.13;q22) karyotype in each of them. No copy-number genomic imbalances were detected by high-density microarray analysis. The mother had a preferential inactivation of the normal X chromosome; expression analysis did not detect any mRNA isoform of NHS. This is the first report of Nance-Horan syndrome due to a skewed X chromosome inactivation resulting from a balanced translocation t(X;1) that disrupts the NHS gene expression, with important implications for clinical presentation and genetic counseling.

  11. Increased enzyme production under liquid culture conditions in the industrial fungus Aspergillus oryzae by disruption of the genes encoding cell wall α-1,3-glucan synthase.

    Science.gov (United States)

    Miyazawa, Ken; Yoshimi, Akira; Zhang, Silai; Sano, Motoaki; Nakayama, Mayumi; Gomi, Katsuya; Abe, Keietsu

    2016-09-01

    Under liquid culture conditions, the hyphae of filamentous fungi aggregate to form pellets, which reduces cell density and fermentation productivity. Previously, we found that loss of α-1,3-glucan in the cell wall of the fungus Aspergillus nidulans increased hyphal dispersion. Therefore, here we constructed a mutant of the industrial fungus A. oryzae in which the three genes encoding α-1,3-glucan synthase were disrupted (tripleΔ). Although the hyphae of the tripleΔ mutant were not fully dispersed, the mutant strain did form smaller pellets than the wild-type strain. We next examined enzyme productivity under liquid culture conditions by transforming the cutinase-encoding gene cutL1 into A. oryzae wild-type and the tripleΔ mutant (i.e. wild-type-cutL1, tripleΔ-cutL1). A. oryzae tripleΔ-cutL1 formed smaller hyphal pellets and showed both greater biomass and increased CutL1 productivity compared with wild-type-cutL1, which might be attributable to a decrease in the number of tripleΔ-cutL1 cells under anaerobic conditions.

  12. Endocrine disruption screening by protein and gene expression of vitellogenin in freshly isolated and cryopreserved rainbow trout hepatocytes.

    Science.gov (United States)

    Markell, Lauren K; Mingoia, Robert T; Peterson, Heather M; Yao, Jianhong; Waters, Stephanie M; Finn, James P; Nabb, Diane L; Han, Xing

    2014-08-18

    Xenobiotics may activate the estrogen receptor, resulting in alteration of normal endocrine functions in animals and humans. Consequently, this necessitates development of assay end points capable of identifying estrogenic xenobiotics. In the present study, we screened the potential estrogenicity of chemicals via their ability to induce vitellogenin (VTG) expression in cultured primary hepatocytes from male trout. A routine method for VTG detection measures the secretion of the protein by enzyme-linked immunosorbent assay (ELISA) in freshly isolated trout hepatocytes. However, this lengthy (6 days) culturing procedure requires that hepatocyte isolation is performed each time the assay is run. We optimized this methodology by investigating the utility of cryopreserved hepatocytes, shortening the incubation time, performing a quantitative real-time PCR (qPCR) method for VTG quantification, and verifying the model system with reference chemicals 17β-estradiol, estrone, diethylstilbestrol, hexestrol, genistein, and a negative control, corticosterone. To test the performance of both freshly isolated and cryopreserved hepatocytes, mRNA was collected from hepatocytes following 24 h treatment for VTG gene expression analysis, whereas cell culture media was collected for a VTG ELISA 96 h post-treatment. EC50 values were obtained for each reference chemical except for corticosterone, which exhibited no induction of VTG gene or protein level. Our results show linear concordance between ELISA and qPCR detection methods. Although there was approximately 50% reduction in VTG inducibility following cryopreservation, linear concordance of EC50 values was found between freshly isolated and cryopreserved hepatocytes, indicating that cryopreservation does not alter the functional assessment of estrogen receptor activation and therefore VTG expression. These studies demonstrate that qPCR is a sensitive and specific method for detecting VTG gene expression that can be used together

  13. The inactivation of the sortilin gene leads to a partial disruption of prosaposin trafficking to the lysosomes

    International Nuclear Information System (INIS)

    Zeng, Jibin; Racicott, Jesse; Morales, Carlos R.

    2009-01-01

    Lysosomes are intracellular organelles which contain enzymes and activator proteins involved in the digestion and recycling of a variety of cellular and extracellular substances. We have identified a novel sorting receptor, sortilin, which is involved in the lysosomal trafficking of the sphingolipid activator proteins, prosaposin and GM 2 AP, and the soluble hydrolases cathepsin D, cathepsin H, and acid sphingomyelinase. Sortilin belongs to a growing family of receptors with homology to the yeast Vps10 protein, which acts as a lysosomal sorting receptor for carboxypeptidase Y. In this study we examined the effects of the sortilin gene inactivation in mice. The inactivation of this gene did not yield any noticeable lysosomal pathology. To determine the existence of an alternative receptor complementing the sorting function of sortilin, we quantified the concentration of prosaposin in the lysosomes of the nonciliated epithelial cells lining the efferent ducts. These cells were chosen because they express sortilin and have a large number of lysosomes containing prosaposin. In addition, the nonciliated cells are known to endocytose luminal prosaposin that is synthesized and secreted by Sertoli cells into the seminiferous luminal fluids. Consequently, the nonciliated cells are capable of targeting both exogenous and endogenous prosaposin to the lysosomes. Using electron microscope immunogold labeling and quantitative analysis, our results demonstrate that inactivation of the sortilin gene produces a significant decrease of prosaposin in the lysosomes. When luminal prosaposin was excluded from the efferent ducts, the level of prosaposin in lysosomes was even lower in the mutant mice. Nonetheless, a significant amount of prosaposin continues to reach the lysosomal compartment. These results strongly suggest the existence of an alternative receptor that complements the function of sortilin and explains the lack of lysosomal storage disorders in the sortilin-deficient mice.

  14. The inactivation of the sortilin gene leads to a partial disruption of prosaposin trafficking to the lysosomes

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Jibin; Racicott, Jesse [Department of Anatomy and Cell Biology, McGill University, Montreal (Canada); Morales, Carlos R., E-mail: carlos.morales@mcgill.ca [Department of Anatomy and Cell Biology, McGill University, Montreal (Canada)

    2009-11-01

    Lysosomes are intracellular organelles which contain enzymes and activator proteins involved in the digestion and recycling of a variety of cellular and extracellular substances. We have identified a novel sorting receptor, sortilin, which is involved in the lysosomal trafficking of the sphingolipid activator proteins, prosaposin and GM{sub 2}AP, and the soluble hydrolases cathepsin D, cathepsin H, and acid sphingomyelinase. Sortilin belongs to a growing family of receptors with homology to the yeast Vps10 protein, which acts as a lysosomal sorting receptor for carboxypeptidase Y. In this study we examined the effects of the sortilin gene inactivation in mice. The inactivation of this gene did not yield any noticeable lysosomal pathology. To determine the existence of an alternative receptor complementing the sorting function of sortilin, we quantified the concentration of prosaposin in the lysosomes of the nonciliated epithelial cells lining the efferent ducts. These cells were chosen because they express sortilin and have a large number of lysosomes containing prosaposin. In addition, the nonciliated cells are known to endocytose luminal prosaposin that is synthesized and secreted by Sertoli cells into the seminiferous luminal fluids. Consequently, the nonciliated cells are capable of targeting both exogenous and endogenous prosaposin to the lysosomes. Using electron microscope immunogold labeling and quantitative analysis, our results demonstrate that inactivation of the sortilin gene produces a significant decrease of prosaposin in the lysosomes. When luminal prosaposin was excluded from the efferent ducts, the level of prosaposin in lysosomes was even lower in the mutant mice. Nonetheless, a significant amount of prosaposin continues to reach the lysosomal compartment. These results strongly suggest the existence of an alternative receptor that complements the function of sortilin and explains the lack of lysosomal storage disorders in the sortilin

  15. Disruption of the acyl-coa binding protein gene delays hepatic adaptation to metabolic changes at weaning

    DEFF Research Database (Denmark)

    Neess, Ditte; Bloksgaard, Maria; Sørensen, Signe Bek

    2011-01-01

    The acyl-CoA binding protein/diazepam binding inhibitor (ACBP/DBI) is an intracellular protein that binds C14-C22 acyl-CoA esters and is thought to act as an acyl-CoA transporter. In vitro analyses have indicated that ACBP can transport acyl-CoA esters between different enzymatic systems; however....... The delayed induction of SREBP target genes around weaning is caused by a compromised processing and decreased expression of SREBP precursors leading to reduced binding of SREBP to target sites in chromatin. In conclusion, lack of ACBP interferes with the normal metabolic adaptation to weaning and leads...

  16. Genetic disruption of the sh3pxd2a gene reveals an essential role in mouse development and the existence of a novel isoform of tks5.

    Science.gov (United States)

    Cejudo-Martin, Pilar; Yuen, Angela; Vlahovich, Nicole; Lock, Peter; Courtneidge, Sara A; Díaz, Begoña

    2014-01-01

    Tks5 is a scaffold protein and Src substrate involved in cell migration and matrix degradation through its essential role in invadosome formation and function. We have previously described that Tks5 is fundamental for zebrafish neural crest cell migration in vivo. In the present study, we sought to investigate the function of Tks5 in mammalian development by analyzing mice mutant for sh3pxd2a, the gene encoding Tks5. Homozygous disruption of the sh3pxd2a gene by gene-trapping in mouse resulted in neonatal death and the presence of a complete cleft of the secondary palate. Interestingly, embryonic fibroblasts from homozygous gene-trap sh3pxd2a mice lacked only the highest molecular weight band of the characteristic Tks5 triplet observed in protein extracts, leaving the lower molecular weight bands unaffected. This finding, together with the existence of two human Expressed Sequence Tags lacking the first 5 exons of SH3PXD2A, made us hypothesize about the presence of a second alternative transcription start site located in intron V. We performed 5'RACE on mouse fibroblasts and isolated a new transcript of the sh3pxd2a gene encoding a novel Tks5 isoform, that we named Tks5β. This novel isoform diverges from the long form of Tks5 in that it lacks the PX-domain, which confers affinity for phosphatidylinositol-3,4-bisphosphate. Instead, Tks5β has a short unique amino terminal sequence encoded by the newly discovered exon 6β; this exon includes a start codon located 29 bp from the 5'-end of exon 6. Tks5β mRNA is expressed in MEFs and all mouse adult tissues analyzed. Tks5β is a substrate for the Src tyrosine kinase and its expression is regulated through the proteasome degradation pathway. Together, these findings indicate the essentiality of the larger Tks5 isoform for correct mammalian development and the transcriptional complexity of the sh3pxd2a gene.

  17. Genetic disruption of the sh3pxd2a gene reveals an essential role in mouse development and the existence of a novel isoform of tks5.

    Directory of Open Access Journals (Sweden)

    Pilar Cejudo-Martin

    Full Text Available Tks5 is a scaffold protein and Src substrate involved in cell migration and matrix degradation through its essential role in invadosome formation and function. We have previously described that Tks5 is fundamental for zebrafish neural crest cell migration in vivo. In the present study, we sought to investigate the function of Tks5 in mammalian development by analyzing mice mutant for sh3pxd2a, the gene encoding Tks5. Homozygous disruption of the sh3pxd2a gene by gene-trapping in mouse resulted in neonatal death and the presence of a complete cleft of the secondary palate. Interestingly, embryonic fibroblasts from homozygous gene-trap sh3pxd2a mice lacked only the highest molecular weight band of the characteristic Tks5 triplet observed in protein extracts, leaving the lower molecular weight bands unaffected. This finding, together with the existence of two human Expressed Sequence Tags lacking the first 5 exons of SH3PXD2A, made us hypothesize about the presence of a second alternative transcription start site located in intron V. We performed 5'RACE on mouse fibroblasts and isolated a new transcript of the sh3pxd2a gene encoding a novel Tks5 isoform, that we named Tks5β. This novel isoform diverges from the long form of Tks5 in that it lacks the PX-domain, which confers affinity for phosphatidylinositol-3,4-bisphosphate. Instead, Tks5β has a short unique amino terminal sequence encoded by the newly discovered exon 6β; this exon includes a start codon located 29 bp from the 5'-end of exon 6. Tks5β mRNA is expressed in MEFs and all mouse adult tissues analyzed. Tks5β is a substrate for the Src tyrosine kinase and its expression is regulated through the proteasome degradation pathway. Together, these findings indicate the essentiality of the larger Tks5 isoform for correct mammalian development and the transcriptional complexity of the sh3pxd2a gene.

  18. Disruption of murine mp29/Syf2/Ntc31 gene results in embryonic lethality with aberrant checkpoint response.

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    Chia-Hsin Chen

    Full Text Available Human p29 is a putative component of spliceosomes, but its role in pre-mRNA is elusive. By siRNA knockdown and stable overexpression, we demonstrated that human p29 is involved in DNA damage response and Fanconi anemia pathway in cultured cells. In this study, we generated p29 knockout mice (mp29(GT/GT using the mp29 gene trap embryonic stem cells to study the role of mp29 in DNA damage response in vivo. Interruption of mp29 at both alleles resulted in embryonic lethality. Embryonic abnormality occurred as early as E6.5 in mp29(GT/GT mice accompanied with decreased mRNA levels of α-tubulin and Chk1. The reduction of α-tubulin and Chk1 mRNAs is likely due to an impaired post-transcriptional event. An aberrant G2/M checkpoint was found in mp29 gene trap embryos when exposed to aphidicolin and UV light. This embryonic lethality was rescued by crossing with mp29 transgenic mice. Additionally, the knockdown of zfp29 in zebrafish resulted in embryonic death at 72 hours of development postfertilization (hpf. A lower level of acetylated α-tubulin was also observed in zfp29 morphants. Together, these results illustrate an indispensable role of mp29 in DNA checkpoint response during embryonic development.

  19. Mutations in THAP1/DYT6 reveal that diverse dystonia genes disrupt similar neuronal pathways and functions.

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    Zuchra Zakirova

    2018-01-01

    Full Text Available Dystonia is characterized by involuntary muscle contractions. Its many forms are genetically, phenotypically and etiologically diverse and it is unknown whether their pathogenesis converges on shared pathways. Mutations in THAP1 [THAP (Thanatos-associated protein domain containing, apoptosis associated protein 1], a ubiquitously expressed transcription factor with DNA binding and protein-interaction domains, cause dystonia, DYT6. There is a unique, neuronal 50-kDa Thap1-like immunoreactive species, and Thap1 levels are auto-regulated on the mRNA level. However, THAP1 downstream targets in neurons, and the mechanism via which it causes dystonia are largely unknown. We used RNA-Seq to assay the in vivo effect of a heterozygote Thap1 C54Y or ΔExon2 allele on the gene transcription signatures in neonatal mouse striatum and cerebellum. Enriched pathways and gene ontology terms include eIF2α Signaling, Mitochondrial Dysfunction, Neuron Projection Development, Axonal Guidance Signaling, and Synaptic LongTerm Depression, which are dysregulated in a genotype and tissue-dependent manner. Electrophysiological and neurite outgrowth assays were consistent with those enrichments, and the plasticity defects were partially corrected by salubrinal. Notably, several of these pathways were recently implicated in other forms of inherited dystonia, including DYT1. We conclude that dysfunction of these pathways may represent a point of convergence in the pathophysiology of several forms of inherited dystonia.

  20. A mutation in the tuft mouse disrupts TET1 activity and alters the expression of genes that are crucial for neural tube closure

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    Keith S. K. Fong

    2016-05-01

    Full Text Available Genetic variations affecting neural tube closure along the head result in malformations of the face and brain. Neural tube defects (NTDs are among the most common birth defects in humans. We previously reported a mouse mutant called tuft that arose spontaneously in our wild-type 3H1 colony. Adult tuft mice present midline craniofacial malformations with or without an anterior cephalocele. In addition, affected embryos presented neural tube closure defects resulting in insufficient closure of the anterior neuropore or exencephaly. Here, through whole-genome sequencing, we identified a nonsense mutation in the Tet1 gene, which encodes a methylcytosine dioxygenase (TET1, co-segregating with the tuft phenotype. This mutation resulted in premature termination that disrupts the catalytic domain that is involved in the demethylation of cytosine. We detected a significant loss of TET enzyme activity in the heads of tuft embryos that were homozygous for the mutation and had NTDs. RNA-Seq transcriptome analysis indicated that multiple gene pathways associated with neural tube closure were dysregulated in tuft embryo heads. Among them, the expressions of Cecr2, Epha7 and Grhl2 were significantly reduced in some embryos presenting neural tube closure defects, whereas one or more components of the non-canonical WNT signaling pathway mediating planar cell polarity and convergent extension were affected in others. We further show that the recombinant mutant TET1 protein was capable of entering the nucleus and affected the expression of endogenous Grhl2 in IMCD-3 (inner medullary collecting duct cells. These results indicate that TET1 is an epigenetic determinant for regulating genes that are crucial to closure of the anterior neural tube and its mutation has implications to craniofacial development, as presented by the tuft mouse.

  1. Disruption of bbe02 by Insertion of a Luciferase Gene Increases Transformation Efficiency of Borrelia burgdorferi and Allows Live Imaging in Lyme Disease Susceptible C3H Mice.

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    Kamfai Chan

    Full Text Available Lyme disease is the most prevalent tick-borne disease in North America and Europe. The causative agent, Borrelia burgdorferi persists in the white-footed mouse. Infection with B. burgdorferi can cause acute to persistent multisystemic Lyme disease in humans. Some disease manifestations are also exhibited in the mouse model of Lyme disease. Genetic manipulation of B. burgdorferi remains difficult. First, B. burgdorferi contains a large number of endogenous plasmids with unique sequences encoding unknown functions. The presence of these plasmids needs to be confirmed after each genetic manipulation. Second, the restriction modification defense systems, including that encoded by bbe02 gene lead to low transformation efficiency in B. burgdorferi. Therefore, studying the molecular basis of Lyme pathogenesis is a challenge. Furthermore, investigation of the role of a specific B. burgdorferi protein throughout infection requires a large number of mice, making it labor intensive and expensive. To overcome the problems associated with low transformation efficiency and to reduce the number of mice needed for experiments, we disrupted the bbe02 gene of a highly infectious and pathogenic B. burgdorferi strain, N40 D10/E9 through insertion of a firefly luciferase gene. The bbe02 mutant shows higher transformation efficiency and maintains luciferase activity throughout infection as detected by live imaging of mice. Infectivity and pathogenesis of this mutant were comparable to the wild-type N40 strain. This mutant will serve as an ideal parental strain to examine the roles of various B. burgdorferi proteins in Lyme pathogenesis in the mouse model in the future.

  2. Genetic disruption of the alternative splicing of drebrin gene impairs context-dependent fear learning in adulthood.

    Science.gov (United States)

    Kojima, N; Hanamura, K; Yamazaki, H; Ikeda, T; Itohara, S; Shirao, T

    2010-01-13

    Dendritic spines are postsynaptic structures at excitatory synapses that play important roles in synaptic transmission and plasticity. Dendritic spine morphology and function are regulated by an actin-based cytoskeletal network. Drebrin A, an adult form of drebrin, is an actin-binding protein in dendritic spines, and its decrease is purportedly concerned with synaptic dysfunction in Alzheimer's disease. Rapid conversion of drebrin E, an embryonic form of drebrin, to drebrin A occurs in parallel with synaptic maturation. To understand the physiological role of drebrin isoform conversion in vivo, we generated knockout mice in which a drebrin A-specific exon was deleted from the drebrin gene. Drebrin A-specific knockout (DAKO) mice expressed drebrin E, which substituted for drebrin A. Subcellular fractionation experiment indicated that cytosolic form of drebrin was increased in the brains of DAKO mice. Furthermore, drebrin accumulation in synaptosomes of DAKO mice was much higher than that of wild-type (WT) mice. DAKO mice were viable and showed no apparent abnormalities in their gross brain morphology and general behaviors. However, DAKO mice were impaired in a context-dependent freezing after fear conditioning. These data indicate that drebrin A plays an indispensable role in some processes of generating fear learning and memory.

  3. Disruption of growth hormone receptor gene causes diminished pancreatic islet size and increased insulin sensitivity in mice.

    Science.gov (United States)

    Liu, Jun-Li; Coschigano, Karen T; Robertson, Katie; Lipsett, Mark; Guo, Yubin; Kopchick, John J; Kumar, Ujendra; Liu, Ye Lauren

    2004-09-01

    Growth hormone, acting through its receptor (GHR), plays an important role in carbohydrate metabolism and in promoting postnatal growth. GHR gene-deficient (GHR(-/-)) mice exhibit severe growth retardation and proportionate dwarfism. To assess the physiological relevance of growth hormone actions, GHR(-/-) mice were used to investigate their phenotype in glucose metabolism and pancreatic islet function. Adult GHR(-/-) mice exhibited significant reductions in the levels of blood glucose and insulin, as well as insulin mRNA accumulation. Immunohistochemical analysis of pancreatic sections revealed normal distribution of the islets despite a significantly smaller size. The average size of the islets found in GHR(-/-) mice was only one-third of that in wild-type littermates. Total beta-cell mass was reduced 4.5-fold in GHR(-/-) mice, significantly more than their body size reduction. This reduction in pancreatic islet mass appears to be related to decreases in proliferation and cell growth. GHR(-/-) mice were different from the human Laron syndrome in serum insulin level, insulin responsiveness, and obesity. We conclude that growth hormone signaling is essential for maintaining pancreatic islet size, stimulating islet hormone production, and maintaining normal insulin sensitivity and glucose homeostasis.

  4. Disruption of KEX1 gene reduces the proteolytic degradation of secreted two-chain Insulin glargine in Pichia pastoris.

    Science.gov (United States)

    Sreenivas, Suma; Krishnaiah, Sateesh M; Shyam Mohan, Anil H; Mallikarjun, Niveditha; Govindappa, Nagaraja; Chatterjee, Amarnath; Sastry, Kedarnath N

    2016-02-01

    Insulin glargine is a slow acting analog of insulin used in diabetes therapy. It is produced by recombinant DNA technology in different hosts namely E. coli and Pichia pastoris. In our previous study, we have described the secretion of fully folded two-chain Insulin glargine into the medium by over-expression of Kex2 protease. The enhanced levels of the Kex2 protease was responsible for the processing of the glargine precursor with in the host. Apart from the two-chain glargine product we observed a small proportion of arginine clipped species. This might be due to the clipping of arginine present at the C-terminus of the B-chain as it is exposed upon Kex2 cleavage. The carboxypeptidase precursor Kex1 is known to be responsible for clipping of C-terminal lysine or arginine of the proteins or peptides. In order to address this issue we created a Kex1 knock out in the host using Cre/loxP mechanism of targeted gene deletion. When two-chain glargine was expressed in the Kex1 knock out host of P. pastoris GS115 the C-terminal clipped species reduced by ∼80%. This modification further improved the process by reducing the levels of product related impurities. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. TALENs-mediated gene disruption of myostatin produces a larger phenotype of medaka with an apparently compromised immune system.

    Science.gov (United States)

    Chiang, Yi-An; Kinoshita, Masato; Maekawa, Shun; Kulkarni, Amod; Lo, Chu-Fang; Yoshiura, Yasutoshi; Wang, Han-Ching; Aoki, Takashi

    2016-01-01

    Although myostatin, a suppressor of skeletal muscle development and growth, has been well studied in mammals, its function in fish remains unclear. In this study, we used a popular genome editing tool with high efficiency and target specificity (TALENs; transcription activator-like effector nucleases) to mutate the genome sequence of myostatin (MSTN) in medaka (Oryzias latipes). After the TALEN pair targeting OlMyostatin was injected into fertilized medaka eggs, mutant G0 fish carrying different TALENs-induced frameshifts in the OlMSTN coding sequence were mated together in order to transmit the mutant sequences to the F1 generation. Two F1 mutants with frameshifted myostatin alleles were then mated to produce the F2 generation, and these F2 OlMSTN null (MSTN(-/-)) medaka were evaluated for growth performance. The F2 fish showed significantly increased body length and weight compared to the wild type fish at the juvenile and post-juvenile stages. At the post-juvenile stage, the average body weight of the MSTN(-/-) medaka was ∼25% greater than the wild type. However, we also found that when the F3 generation were challenged with red spotted grouper nervous necrosis virus (RGNNV), the expression levels of the interferon-stimulated genes were lower than in the wild type, and the virus copy number was maintained at a high level. We therefore conclude that although the MSTN(-/-) medaka had a larger phenotype, their immune system appeared to be at least partially suppressed or undeveloped. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. TAD disruption as oncogenic driver.

    Science.gov (United States)

    Valton, Anne-Laure; Dekker, Job

    2016-02-01

    Topologically Associating Domains (TADs) are conserved during evolution and play roles in guiding and constraining long-range regulation of gene expression. Disruption of TAD boundaries results in aberrant gene expression by exposing genes to inappropriate regulatory elements. Recent studies have shown that TAD disruption is often found in cancer cells and contributes to oncogenesis through two mechanisms. One mechanism locally disrupts domains by deleting or mutating a TAD boundary leading to fusion of the two adjacent TADs. The other mechanism involves genomic rearrangements that break up TADs and creates new ones without directly affecting TAD boundaries. Understanding the mechanisms by which TADs form and control long-range chromatin interactions will therefore not only provide insights into the mechanism of gene regulation in general, but will also reveal how genomic rearrangements and mutations in cancer genomes can lead to misregulation of oncogenes and tumor suppressors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Disruption of the pdhB pyruvate dehydrogenase [corrected] gene affects colony morphology, in vitro growth and cell invasiveness of Mycoplasma agalactiae.

    Directory of Open Access Journals (Sweden)

    Shivanand Hegde

    Full Text Available The utilization of available substrates, the metabolic potential and the growth rates of bacteria can play significant roles in their pathogenicity. This study concentrates on Mycoplasma agalactiae, which causes significant economic losses through its contribution to contagious agalactia in small ruminants by as yet unknown mechanisms. This lack of knowledge is primarily due to its fastidious growth requirements and the scarcity of genetic tools available for its manipulation and analysis. Transposon mutagenesis of M. agalactiae type strain PG2 resulted in several disruptions throughout the genome. A mutant defective in growth in vitro was found to have a transposon insertion in the pdhB gene, which encodes a component of the pyruvate dehydrogenase complex. This growth difference was quite significant during the actively dividing logarithmic phase but a gradual recovery was observed as the cells approached stationary phase. The mutant also exhibited a different and smaller colony morphology compared to the wild type strain PG2. For complementation, pdhAB was cloned downstream of a strong vpma promoter and upstream of a lacZ reporter gene in a newly constructed complementation vector. When transformed with this vector the pdhB mutant recovered its normal growth and colony morphology. Interestingly, the pdhB mutant also had significantly reduced invasiveness in HeLa cells, as revealed by double immunofluorescence staining. This deficiency was recovered in the complemented strain, which had invasiveness comparable to that of PG2. Taken together, these data indicate that pyruvate dehydrogenase might be an important player in infection with and colonization by M. agalactiae.

  8. Fish oil improves motor function, limits blood-brain barrier disruption, and reduces Mmp9 gene expression in a rat model of juvenile traumatic brain injury.

    Science.gov (United States)

    Russell, K L; Berman, N E J; Gregg, P R A; Levant, B

    2014-01-01

    The effects of an oral fish oil treatment regimen on sensorimotor, blood-brain barrier, and biochemical outcomes of traumatic brain injury (TBI) were investigated in a juvenile rat model. Seventeen-day old Long-Evans rats were given a 15mL/kg fish oil (2.01g/kg EPA, 1.34g/kg DHA) or soybean oil dose via oral gavage 30min prior to being subjected to a controlled cortical impact injury or sham surgery, followed by daily doses for seven days. Fish oil treatment resulted in less severe hindlimb deficits after TBI as assessed with the beam walk test, decreased cerebral IgG infiltration, and decreased TBI-induced expression of the Mmp9 gene one day after injury. These results indicate that fish oil improved functional outcome after TBI resulting, at least in part from decreased disruption of the blood-brain barrier through a mechanism that includes attenuation of TBI-induced expression of Mmp9. © 2013 Elsevier Ltd. All rights reserved.

  9. Disruption of M-T5, a novel myxoma virus gene member of poxvirus host range superfamily, results in dramatic attenuation of myxomatosis in infected European rabbits.

    Science.gov (United States)

    Mossman, K; Lee, S F; Barry, M; Boshkov, L; McFadden, G

    1996-07-01

    Myxoma virus is a pathogenic poxvirus that induces a lethal myxomatosis disease profile in European rabbits, which is characterized by fulminating lesions at the primary site of inoculation, rapid dissemination to secondary internal organs and peripheral external sites, and supervening gram-negative bacterial infection. Here we describe the role of a novel myxoma virus protein encoded by the M-T5 open reading frame during pathogenesis. The myxoma virus M-T5 protein possesses no significant sequence homology to nonviral proteins but is a member of a larger poxviral superfamily designated host range proteins. An M-T5- mutant virus was constructed by disruption of both copies of the M-T5 gene followed by insertion of the selectable marker p7.5Ecogpt. Although the M-T5- deletion mutant replicated with wild-type kinetics in rabbit fibroblasts, infection of a rabbit CD4+ T-cell line (RL5) with the myxoma virus M-T5- mutant virus resulted in the rapid and complete cessation of both host and viral protein synthesis, accompanied by the manifestation of all the classical features of programmed cell death. Infection of primary rabbit peripheral mononuclear cells with the myxoma virus M-T5-mutant virus resulted in the apoptotic death of nonadherent lymphocytes but not adherent monocytes. Within the European rabbit, disruption of the M-T5 open reading frame caused a dramatic attenuation of the rapidly lethal myxomatosis infection, and none of the infected rabbits displayed any of the characteristic features of myxomatosis. The two most significant histological observations in rabbits infected with the M-T5-mutant virus were (i) the lack of progression of the infection past the primary site of inoculation, coupled with the establishment of a rapid and effective inflammatory reaction, and (ii) the inability of the virus to initiate a cellular reaction within secondary immune organs. We conclude that M-T5 functions as a critical virulence factor by allowing productive infection of

  10. Neuroendocrine disruption in the shore crab Carcinus maenas: Effects of serotonin and fluoxetine on chh- and mih-gene expression, glycaemia and ecdysteroid levels.

    Science.gov (United States)

    Robert, Alexandrine; Monsinjon, Tiphaine; Delbecque, Jean-Paul; Olivier, Stéphanie; Poret, Agnès; Foll, Frank Le; Durand, Fabrice; Knigge, Thomas

    2016-06-01

    Serotonin, a highly conserved neurotransmitter, controls many biological functions in vertebrates, but also in invertebrates. Selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine, are commonly used in human medication to ease depression by affecting serotonin levels. Their residues and metabolites can be detected in the aquatic environment and its biota. They may also alter serotonin levels in aquatic invertebrates, thereby perturbing physiological functions. To investigate whether such perturbations can indeed be expected, shore crabs (Carcinus maenas) were injected either with serotonin, fluoxetine or a combination of both. Dose-dependent effects of fluoxetine ranging from 250 to 750nM were investigated. Gene expression of crustacean hyperglycemic hormone (chh) as well as moult inhibiting hormone (mih) was assessed by RT-qPCR at 2h and 12h after injection. Glucose and ecdysteroid levels in the haemolymph were monitored in regular intervals until 12h. Serotonin led to a rapid increase of chh and mih expression. On the contrary, fluoxetine only affected chh and mih expression after several hours, but kept expression levels significantly elevated. Correspondingly, serotonin rapidly increased glycaemia, which returned to normal or below normal levels after 12h. Fluoxetine, however, resulted in a persistent low-level increase of glycaemia, notably during the period when negative feedback regulation reduced glycaemia in the serotonin treated animals. Ecdysteroid levels were significantly decreased by serotonin and fluoxetine, with the latter showing less pronounced and less rapid, but longer lasting effects. Impacts of fluoxetine on glycaemia and ecdysteroids were mostly observed at higher doses (500 and 750nM) and affected principally the response dynamics, but not the amplitude of glycaemia and ecdysteroid-levels. These results suggest that psychoactive drugs are able to disrupt neuroendocrine control in decapod crustaceans, as they interfere with the

  11. Detailed analysis of targeted gene mutations caused by the Platinum-Fungal TALENs in Aspergillus oryzae RIB40 strain and a ligD disruptant.

    Science.gov (United States)

    Mizutani, Osamu; Arazoe, Takayuki; Toshida, Kenji; Hayashi, Risa; Ohsato, Shuichi; Sakuma, Tetsushi; Yamamoto, Takashi; Kuwata, Shigeru; Yamada, Osamu

    2017-03-01

    Transcription activator-like effector nucleases (TALENs), which can generate DNA double-strand breaks at specific sites in the desired genome locus, have been used in many organisms as a tool for genome editing. In Aspergilli, including Aspergillus oryzae, however, the use of TALENs has not been validated. In this study, we performed genome editing of A. oryzae wild-type strain via error of nonhomologous end-joining (NHEJ) repair by transient expression of high-efficiency Platinum-Fungal TALENs (PtFg TALENs). Targeted mutations were observed as various mutation patterns. In particular, approximately half of the PtFg TALEN-mediated deletion mutants had deletions larger than 1 kb in the TALEN-targeting region. We also conducted PtFg TALEN-based genome editing in A. oryzae ligD disruptant (ΔligD) lacking the ligD gene involved in the final step of the NHEJ repair and found that mutations were still obtained as well as wild-type. In this case, the ratio of the large deletions reduced compared to PtFg TALEN-based genome editing in the wild-type. In conclusion, we demonstrate that PtFg TALENs are sufficiently functional to cause genome editing via error of NHEJ in A. oryzae. In addition, we reveal that genome editing using TALENs in A. oryzae tends to cause large deletions at the target region, which were partly suppressed by deletion of ligD. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  12. Sustainable Disruptions

    DEFF Research Database (Denmark)

    Friis, Silje Alberthe Kamille; Kjær, Lykke Bloch

    2016-01-01

    Since 2012 the Sustainable Disruptions (SD) project at the Laboratory for Sustainability at Design School Kolding (DK) has developed and tested a set of design thinking tools, specifically targeting the barriers to economically, socially, and environmentally sustainable business development....... The tools have been applied in practice in collaboration with 11 small and medium sized companies (SMEs). The study investigates these approaches to further understand how design thinking can contribute to sustainable transition in a business context. The study and the findings are relevant to organizations...... invested in the issue of sustainable business development, in particular the leaders and employees of SMEs, but also to design education seeking new ways to consciously handle and teach the complexity inherent in sustainable transformation. Findings indicate that the SD design thinking approach contributes...

  13. Endocrine Disrupting Chemicals (EDCs)

    Science.gov (United States)

    ... Center Pacientes y Cuidadores Hormones and Health The Endocrine System Hormones Endocrine Disrupting Chemicals (EDCs) Steroid and Hormone ... Hormones and Health › Endocrine Disrupting Chemicals (EDCs) The Endocrine System Hormones Endocrine Disrupting Chemicals (EDCs) EDCs Myth vs. ...

  14. Effect of disruption of a cutinase gene (cutA) on virulence and tissue specificity of Fusarium solani f. sp. cucurbitae race 2 toward Cucurbita maxima and C. moschata.

    Science.gov (United States)

    Crowhurst, R N; Binnie, S J; Bowen, J K; Hawthorne, B T; Plummer, K M; Rees-George, J; Rikkerink, E H; Templeton, M D

    1997-04-01

    A 3.9-kb genomic DNA fragment from the cucurbit pathogen Fusarium solani f. sp. cucurbitae race 2 was cloned. Sequence analysis revealed an open reading frame of 690 nucleotides interrupted by a single 51-bp intron. The nucleotide and predicted amino acid sequences showed 92 and 98% identity, respectively, to those of the cutA gene of the pea pathogen F. solani f. sp. pisi. A gene replacement vector was constructed and used to generate cutA- mutants that were detected with a polymerase chain reaction (PCR) assay. Seventy-one cutA- mutants were identified among the 416 transformants screened. Vector integration was assessed by Southern analysis in 23 of these mutants. PCR and Southern analysis data showed the level of homologous integration was 14%. Disruption of the cutA locus in mutants was confirmed by RNA gel blot hybridization. Neither virulence on Cucurbita maxima cv. Delica at any of six different inoculum concentrations, nor pathogenicity on intact fruit of four different species or cultivars of cucurbit or hypocotyl tissue of C. maxima cv. Crown, was found to be affected by disruption of the cutA gene.

  15. PARK2, a Large Common Fragile Site Gene, is Part of a Stress Response Network in Normal Cells That is Disrupted During the Development of Ovarian Cancer

    National Research Council Canada - National Science Library

    Smith, David I; Zhu, Yu

    2007-01-01

    .... The central two questions that we want to address with this work are what role does inactivation of Parkin and other large CFS genes play in the development of ovarian cancer and whether these genes...

  16. Disruption of Zebrafish Follicle-Stimulating Hormone Receptor (fshr) But Not Luteinizing Hormone Receptor (lhcgr) Gene by TALEN Leads to Failed Follicle Activation in Females Followed by Sexual Reversal to Males.

    Science.gov (United States)

    Zhang, Zhiwei; Lau, Shuk-Wa; Zhang, Lingling; Ge, Wei

    2015-10-01

    Gonadotropins are primary hormones that control vertebrate reproduction. In a recent study, we analyzed the impacts of FSH and LH on zebrafish reproduction by disrupting FSH and LH-β genes (fshb and lhb) using transcription activator-like effector nuclease (TALEN) technology. Using the same approach, we successfully deleted FSH and LH receptor genes (fshr and lhcgr) in the present study. In contrast to the deficiency of its cognate ligand FSH, the fshr-deficient females showed a complete failure of follicle activation with all ovarian follicles arrested at the primary growth-previtellogenic transition, which is the marker for puberty onset in females. Interestingly, after blockade at the primary growth stage for varying times, all females reversed to males, and all these males were fertile. In fshr-deficient males, spermatogenesis was normal in adults, but the initiation of spermatogenesis in juveniles was retarded. In contrast to fshr, the deletion of the lhcgr gene alone caused no obvious phenotypes in both males and females; however, double mutation of fshr and lhcgr resulted in infertile males. In summary, our results in the present study showed that Fshr was indispensable to folliculogenesis and the disruption of the fshr gene resulted in a complete failure of follicle activation followed by masculinization into males. In contrast, lhcgr does not seem to be essential to zebrafish reproduction in both males and females. Neither Fshr nor Lhcgr deficiency could phenocopy the deficiency of their cognate ligands FSH and LH, which is likely due to the fact that Fshr can be activated by both FSH and LH in the zebrafish.

  17. PARK2, a Large Common Fragile Site Gene, is Part of a Stress Response Network in Normal Cells that is Disrupted During the Development of Ovarian Cancer

    National Research Council Canada - National Science Library

    Smith, David I

    2005-01-01

    .... The central two questions that we want to address with this work are what role does the inactivation of Parkin play in the development of ovarian cancer and whether this gene functions as part...

  18. A lack of immune system genes causes loss in high frequency hearing but does not disrupt cochlear synapse maturation in mice.

    Science.gov (United States)

    Calton, Melissa A; Lee, Dasom; Sundaresan, Srividya; Mendus, Diana; Leu, Rose; Wangsawihardja, Felix; Johnson, Kenneth R; Mustapha, Mirna

    2014-01-01

    Early cochlear development is marked by an exuberant outgrowth of neurites that innervate multiple targets. The establishment of mature cochlear neural circuits is, however, dependent on the pruning of inappropriate axons and synaptic connections. Such refinement also occurs in the central nervous system (CNS), and recently, genes ordinarily associated with immune and inflammatory processes have been shown to play roles in synaptic pruning in the brain. These molecules include the major histocompatibility complex class I (MHCI) genes, H2-K(b) and H2-D(b), and the complement cascade gene, C1qa. Since the mechanisms involved in synaptic refinement in the cochlea are not well understood, we investigated whether these immune system genes may be involved in this process and whether they are required for normal hearing function. Here we report that these genes are not necessary for normal synapse formation and refinement in the mouse cochlea. We further demonstrate that C1qa expression is not necessary for normal hearing in mice but the lack of expression of H2-K(b) and H2-D(b) causes hearing impairment. These data underscore the importance of the highly polymorphic family of MHCI genes in hearing in mice and also suggest that factors and mechanisms regulating synaptic refinement in the cochlea may be distinct from those in the CNS.

  19. Fluoxetine normalizes disrupted light-induced entrainment, fragmented ultradian rhythms and altered hippocampal clock gene expression in an animal model of high trait anxiety- and depression-related behavior.

    Science.gov (United States)

    Schaufler, Jörg; Ronovsky, Marianne; Savalli, Giorgia; Cabatic, Maureen; Sartori, Simone B; Singewald, Nicolas; Pollak, Daniela D

    2016-01-01

    Disturbances of circadian rhythms are a key symptom of mood and anxiety disorders. Selective serotonin reuptake inhibitors (SSRIs) - commonly used antidepressant drugs - also modulate aspects of circadian rhythmicity. However, their potential to restore circadian disturbances in depression remains to be investigated. The effects of the SSRI fluoxetine on genetically based, depression-related circadian disruptions at the behavioral and molecular level were examined using mice selectively bred for high anxiety-related and co-segregating depression-like behavior (HAB) and normal anxiety/depression behavior mice (NAB). The length of the circadian period was increased in fluoxetine-treated HAB as compared to NAB mice while the number of activity bouts and light-induced entrainment were comparable. No difference in hippocampal Cry2 expression, previously reported to be dysbalanced in untreated HAB mice, was observed, while Per2 and Per3 mRNA levels were higher in HAB mice under fluoxetine treatment. The present findings provide evidence that fluoxetine treatment normalizes disrupted circadian locomotor activity and clock gene expression in a genetic mouse model of high trait anxiety and depression. An interaction between the molecular mechanisms mediating the antidepressant response to fluoxetine and the endogenous regulation of circadian rhythms in genetically based mood and anxiety disorders is proposed.

  20. Disruption of the ECM33 Gene in Candida albicans Prevents Biofilm Formation, Engineered Human Oral Mucosa Tissue Damage and Gingival Cell Necrosis/Apoptosis

    Directory of Open Access Journals (Sweden)

    Mahmoud Rouabhia

    2012-01-01

    Full Text Available In this study we demonstrated that ΔCaecm33 double mutant showed reduced biofilm formation and causes less damage to gingival mucosa tissues. This was confirmed by the reduced level of necrotic cells and Bax/Bcl2 gene expression as apoptotic markers. In contrast, parental and Caecm33 mutant strains decreased basement membrane protein production (laminin 5 and type IV collagen. We thus propose that ECM33 gene/protein represents a novel target for the prevention and treatment of infections caused by Candida.

  1. Oncogenicity of L-type amino-acid transporter 1 (LAT1) revealed by targeted gene disruption in chicken DT40 cells: LAT1 is a promising molecular target for human cancer therapy

    Energy Technology Data Exchange (ETDEWEB)

    Ohkawa, Mayumi [Molecular Cell Biology Laboratory, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba Aramaki, Aoba-ku, Sendai 980-8578 (Japan); Ohno, Yoshiya [Laboratory of Immunobiology, Department of Pharmacy, School of Pharmacy, Hyogo University of Health Sciences, Kobe-shi, Hyogo 650-8530 (Japan); Masuko, Kazue; Takeuchi, Akiko; Suda, Kentaro; Kubo, Akihiro; Kawahara, Rieko; Okazaki, Shogo [Cell Biology Laboratory, Department of Pharmaceutical Sciences, School of Pharmacy, Kinki University, 4-1 Kowakae 3-chome, Higashiosaka-shi, Osaka 577-8502 (Japan); Tanaka, Toshiyuki [Laboratory of Immunobiology, Department of Pharmacy, School of Pharmacy, Hyogo University of Health Sciences, Kobe-shi, Hyogo 650-8530 (Japan); Saya, Hideyuki [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8502 (Japan); Seki, Masayuki; Enomoto, Takemi [Molecular Cell Biology Laboratory, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba Aramaki, Aoba-ku, Sendai 980-8578 (Japan); Yagi, Hideki [Cell Biology Laboratory, Department of Pharmaceutical Sciences, School of Pharmacy, Kinki University, 4-1 Kowakae 3-chome, Higashiosaka-shi, Osaka 577-8502 (Japan); Hashimoto, Yoshiyuki [Tohoku University, Sendai (Japan); Masuko, Takashi, E-mail: masuko@phar.kindai.ac.jp [Cell Biology Laboratory, Department of Pharmaceutical Sciences, School of Pharmacy, Kinki University, 4-1 Kowakae 3-chome, Higashiosaka-shi, Osaka 577-8502 (Japan)

    2011-03-25

    Highlights: {yields} We established LAT1 amino-acid transporter-disrupted DT40 cells. {yields} LAT1-disrupted cells showed slow growth and lost the oncogenicity. {yields} siRNA and mAb inhibited human tumor growth in vitro and in vivo. {yields} LAT1 is a promising target molecule for cancer therapy. -- Abstract: L-type amino-acid transporter 1 (LAT1) is the first identified light chain of CD98 molecule, disulfide-linked to a heavy chain of CD98. Following cDNA cloning of chicken full-length LAT1, we have constructed targeting vectors for the disruption of chicken LAT1 gene from genomic DNA of chicken LAT1 consisting of 5.4 kb. We established five homozygous LAT1-disrupted (LAT1{sup -/-}) cell clones, derived from a heterozygous LAT1{sup +/-} clone of DT40 chicken B cell line. Reactivity of anti-chicken CD98hc monoclonal antibody (mAb) with LAT1{sup -/-} DT40 cells was markedly decreased compared with that of wild-type DT40 cells. All LAT1{sup -/-} cells were deficient in L-type amino-acid transporting activity, although alternative-splice variant but not full-length mRNA of LAT1 was detected in these cells. LAT1{sup -/-} DT40 clones showed outstandingly slow growth in liquid culture and decreased colony-formation capacity in soft agar compared with wild-type DT40 cells. Cell-cycle analyses indicated that LAT1{sup -/-} DT40 clones have prolonged cell-cycle phases compared with wild-type or LAT1{sup +/-} DT40 cells. Knockdown of human LAT1 by small interfering RNAs resulted in marked in vitro cell-growth inhibition of human cancer cells, and in vivo tumor growth of HeLa cells in athymic mice was significantly inhibited by anti-human LAT1 mAb. All these results indicate essential roles of LAT1 in the cell proliferation and occurrence of malignant phenotypes and that LAT1 is a promising candidate as a molecular target of human cancer therapy.

  2. Oncogenicity of L-type amino-acid transporter 1 (LAT1) revealed by targeted gene disruption in chicken DT40 cells: LAT1 is a promising molecular target for human cancer therapy

    International Nuclear Information System (INIS)

    Ohkawa, Mayumi; Ohno, Yoshiya; Masuko, Kazue; Takeuchi, Akiko; Suda, Kentaro; Kubo, Akihiro; Kawahara, Rieko; Okazaki, Shogo; Tanaka, Toshiyuki; Saya, Hideyuki; Seki, Masayuki; Enomoto, Takemi; Yagi, Hideki; Hashimoto, Yoshiyuki; Masuko, Takashi

    2011-01-01

    Highlights: → We established LAT1 amino-acid transporter-disrupted DT40 cells. → LAT1-disrupted cells showed slow growth and lost the oncogenicity. → siRNA and mAb inhibited human tumor growth in vitro and in vivo. → LAT1 is a promising target molecule for cancer therapy. -- Abstract: L-type amino-acid transporter 1 (LAT1) is the first identified light chain of CD98 molecule, disulfide-linked to a heavy chain of CD98. Following cDNA cloning of chicken full-length LAT1, we have constructed targeting vectors for the disruption of chicken LAT1 gene from genomic DNA of chicken LAT1 consisting of 5.4 kb. We established five homozygous LAT1-disrupted (LAT1 -/- ) cell clones, derived from a heterozygous LAT1 +/- clone of DT40 chicken B cell line. Reactivity of anti-chicken CD98hc monoclonal antibody (mAb) with LAT1 -/- DT40 cells was markedly decreased compared with that of wild-type DT40 cells. All LAT1 -/- cells were deficient in L-type amino-acid transporting activity, although alternative-splice variant but not full-length mRNA of LAT1 was detected in these cells. LAT1 -/- DT40 clones showed outstandingly slow growth in liquid culture and decreased colony-formation capacity in soft agar compared with wild-type DT40 cells. Cell-cycle analyses indicated that LAT1 -/- DT40 clones have prolonged cell-cycle phases compared with wild-type or LAT1 +/- DT40 cells. Knockdown of human LAT1 by small interfering RNAs resulted in marked in vitro cell-growth inhibition of human cancer cells, and in vivo tumor growth of HeLa cells in athymic mice was significantly inhibited by anti-human LAT1 mAb. All these results indicate essential roles of LAT1 in the cell proliferation and occurrence of malignant phenotypes and that LAT1 is a promising candidate as a molecular target of human cancer therapy.

  3. Targeted disruption in mice of a neural stem cell-maintaining, KRAB-Zn finger-encoding gene that has rapidly evolved in the human lineage.

    Directory of Open Access Journals (Sweden)

    Huan-Chieh Chien

    Full Text Available Understanding the genetic basis of the physical and behavioral traits that separate humans from other primates is a challenging but intriguing topic. The adaptive functions of the expansion and/or reduction in human brain size have long been explored. From a brain transcriptome project we have identified a KRAB-Zn finger protein-encoding gene (M003-A06 that has rapidly evolved since the human-chimpanzee separation. Quantitative RT-PCR analysis of different human tissues indicates that M003-A06 expression is enriched in the human fetal brain in addition to the fetal heart. Furthermore, analysis with use of immunofluorescence staining, neurosphere culturing and Western blotting indicates that the mouse ortholog of M003-A06, Zfp568, is expressed mainly in the embryonic stem (ES cells and fetal as well as adult neural stem cells (NSCs. Conditional gene knockout experiments in mice demonstrates that Zfp568 is both an NSC maintaining- and a brain size-regulating gene. Significantly, molecular genetic analyses show that human M003-A06 consists of 2 equilibrated allelic types, H and C, one of which (H is human-specific. Combined contemporary genotyping and database mining have revealed interesting genetic associations between the different genotypes of M003-A06 and the human head sizes. We propose that M003-A06 is likely one of the genes contributing to the uniqueness of the human brain in comparison to other higher primates.

  4. RNA interference silences Microplitis demolitor bracovirus genes and implicates glc1.8 in disruption of adhesion in infected host cells

    International Nuclear Information System (INIS)

    Beck, Markus; Strand, Michael R.

    2003-01-01

    The family Polydnaviridae consists of ds-DNA viruses that are symbiotically associated with certain parasitoid wasps. PDVs are transmitted vertically but also are injected by wasps into hosts where they cause several physiological alterations including immunosuppression. The PDV genes responsible for mediating immunosuppression and other host alterations remain poorly characterized in large measure because viral mutants cannot be produced to study gene function. Here we report the use of RNA interference (RNAi) to specifically silence the glc1.8 and egf1.0 genes from Microplitis demolitor bracovirus (MdBV) in High Five cells derived from the lepidopteran Trichoplusia ni. Dose-response studies indicated that MdBV infects High Five cells and blocks the ability of these cells to adhere to culture plates. This response was very similar to what occurs in two classes of hemocytes, granular cells, and plasmatocytes, after infection by MdBV. Screening of monoclonal antibody (mAb) markers that distinguish different classes of lepidopteran hemocytes indicated that High Five cells cross-react with three mAbs that recognize granular cells from T. ni. Double-stranded RNA (dsRNA) complementary to glc1.8 specifically silenced glc1.8 expression and rescued the adhesive phenotype of High Five cells. Reciprocally, dsRNA complementary to egf1.0 silenced egf1.0 expression but had no effect on adhesion. The simplicity and potency of RNAi could be extremely useful for analysis of other PDV genes

  5. Structure of the Elastin-Contractile Units in the Thoracic Aorta and How Genes That Cause Thoracic Aortic Aneurysms and Dissections Disrupt This Structure.

    Science.gov (United States)

    Karimi, Ashkan; Milewicz, Dianna M

    2016-01-01

    The medial layer of the aorta confers elasticity and strength to the aortic wall and is composed of alternating layers of smooth muscle cells (SMCs) and elastic fibres. The SMC elastin-contractile unit is a structural unit that links the elastin fibres to the SMCs and is characterized by the following: (1) layers of elastin fibres that are surrounded by microfibrils; (2) microfibrils that bind to the integrin receptors in focal adhesions on the cell surface of the SMCs; and (3) SMC contractile filaments that are linked to the focal adhesions on the inner side of the membrane. The genes that are altered to cause thoracic aortic aneurysms and aortic dissections encode proteins involved in the structure or function of the SMC elastin-contractile unit. Included in this gene list are the genes encoding protein that are structural components of elastin fibres and microfibrils, FBN1, MFAP5, ELN, and FBLN4. Also included are genes that encode structural proteins in the SMC contractile unit, including ACTA2, which encodes SMC-specific α-actin and MYH11, which encodes SMC-specific myosin heavy chain, along with MYLK and PRKG1, which encode kinases that control SMC contraction. Finally, mutations in the gene encoding the protein linking integrin receptors to the contractile filaments, FLNA, also predispose to thoracic aortic disease. Thus, these data suggest that functional SMC elastin-contractile units are important for maintaining the structural integrity of the aorta. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  6. Adenoviral gene transfer of PLD1-D4 enhances insulin sensitivity in mice by disrupting phospholipase D1 interaction with PED/PEA-15.

    Directory of Open Access Journals (Sweden)

    Angela Cassese

    Full Text Available Over-expression of phosphoprotein enriched in diabetes/phosphoprotein enriched in astrocytes (PED/PEA-15 causes insulin resistance by interacting with the D4 domain of phospholipase D1 (PLD1. Indeed, the disruption of this association restores insulin sensitivity in cultured cells over-expressing PED/PEA-15. Whether the displacement of PLD1 from PED/PEA-15 improves insulin sensitivity in vivo has not been explored yet. In this work we show that treatment with a recombinant adenoviral vector containing the human D4 cDNA (Ad-D4 restores normal glucose homeostasis in transgenic mice overexpressing PED/PEA-15 (Tg ped/pea-15 by improving both insulin sensitivity and secretion. In skeletal muscle of these mice, D4 over-expression inhibited PED/PEA-15-PLD1 interaction, decreased Protein Kinase C alpha activation and restored insulin induced Protein Kinase C zeta activation, leading to amelioration of insulin-dependent glucose uptake. Interestingly, Ad-D4 administration improved insulin sensitivity also in high-fat diet treated obese C57Bl/6 mice. We conclude that PED/PEA-15-PLD1 interaction may represent a novel target for interventions aiming at improving glucose tolerance.

  7. The effects of disruption of phosphoglucose isomerase gene on carbon utilisation and cellulase production in Trichoderma reesei Rut-C30

    Science.gov (United States)

    2011-01-01

    Background Cellulase and hemicellulase genes in the fungus Trichoderma reesei are repressed by glucose and induced by lactose. Regulation of the cellulase genes is mediated by the repressor CRE1 and the activator XYR1. T. reesei strain Rut-C30 is a hypercellulolytic mutant, obtained from the natural strain QM6a, that has a truncated version of the catabolite repressor gene, cre1. It has been previously shown that bacterial mutants lacking phosphoglucose isomerase (PGI) produce more nucleotide precursors and amino acids. PGI catalyzes the second step of glycolysis, the formation of fructose-6-P from glucose-6-P. Results We deleted the gene pgi1, encoding PGI, in the T. reesei strain Rut-C30 and we introduced the cre1 gene in a Δpgi1 mutant. Both Δpgi1 and cre1+Δpgi1 mutants showed a pellet-like and growth as well as morphological alterations compared with Rut-C30. None of the mutants grew in media with fructose, galactose, xylose, glycerol or lactose but they grew in media with glucose, with fructose and glucose, with galactose and fructose or with lactose and fructose. No growth was observed in media with xylose and glucose. On glucose, Δpgi1 and cre1+Δpgi1 mutants showed higher cellulase activity than Rut-C30 and QM6a, respectively. But in media with lactose, none of the mutants improved the production of the reference strains. The increase in the activity did not correlate with the expression of mRNA of the xylanase regulator gene, xyr1. Δpgi1 mutants were also affected in the extracellular β-galactosidase activity. Levels of mRNA of the glucose 6-phosphate dehydrogenase did not increase in Δpgi1 during growth on glucose. Conclusions The ability to grow in media with glucose as the sole carbon source indicated that Trichoderma Δpgi1 mutants were able to use the pentose phosphate pathway. But, they did not increase the expression of gpdh. Morphological characteristics were the result of the pgi1 deletion. Deletion of pgi1 in Rut-C30 increased cellulase

  8. Combination of Hypomorphic Mutations of the Drosophila Homologues of Aryl Hydrocarbon Receptor and Nucleosome Assembly Protein Family Genes Disrupts Morphogenesis, Memory and Detoxification

    OpenAIRE

    Kuzin, Boris A.; Nikitina, Ekaterina A.; Cherezov, Roman O.; Vorontsova, Julia E.; Slezinger, Mikhail S.; Zatsepina, Olga G.; Simonova, Olga B.; Enikolopov, Grigori N.; Savvateeva-Popova, Elena V.

    2014-01-01

    Aryl hydrocarbon receptor is essential for biological responses to endogenous and exogenous toxins in mammals. Its Drosophila homolog spineless plays an important role in fly morphogenesis. We have previously shown that during morphogenesis spineless genetically interacts with CG5017 gene, which encodes a nucleosome assembly factor and may affect cognitive function of the fly. We now demonstrate synergistic interactions of spineless and CG5017 in pathways controlling oxidative stress response...

  9. Disruption of gene pqqA or pqqB reduces plant growth promotion activity and biocontrol of crown gall disease by Rahnella aquatilis HX2.

    Directory of Open Access Journals (Sweden)

    Lei Li

    Full Text Available Rahnella aquatilis strain HX2 has the ability to promote maize growth and suppress sunflower crown gall disease caused by Agrobacterium vitis, A. tumefaciens, and A. rhizogenes. Pyrroloquinoline quinone (PQQ, a cofactor of aldose and alcohol dehydrogenases, is required for the synthesis of an antibacterial substance, gluconic acid, by HX2. Mutants of HX2 unable to produce PQQ were obtained by in-frame deletion of either the pqqA or pqqB gene. In this study, we report the independent functions of pqqA and pqqB genes in relation to PQQ synthesis. Interestingly, both the pqqA and pqqB mutants of R. aquatilis eliminated the ability of strain HX2 to produce antibacterial substance, which in turn, reduced the effectiveness of the strain for biological control of sunflower crown gall disease. The mutation also resulted in decreased mineral phosphate solubilization by HX2, which reduced the efficacy of this strain as a biological fertilizer. These functions were restored by complementation with the wild-type pqq gene cluster. Additionally, the phenotypes of HX2 derivatives, including colony morphology, growth dynamic, and pH change of culture medium were impacted to different extents. Our findings suggested that pqqA and pqqB genes individually play important functions in PQQ biosynthesis and are required for antibacterial activity and phosphorous solubilization. These traits are essential for R. aquatilis efficacy as a biological control and plant growth promoting strain. This study enhances our fundamental understanding of the biosynthesis of an environmentally significant cofactor produced by a promising biocontrol and biological fertilizer strain.

  10. Melatonin Attenuates Potato Late Blight by Disrupting Cell Growth, Stress Tolerance, Fungicide Susceptibility and Homeostasis of Gene Expression in Phytophthora infestans

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    Shumin Zhang

    2017-11-01

    Full Text Available Phytophthora infestans (P. infestans is the causal agent of potato late blight, which caused the devastating Irish Potato Famine during 1845-1852. Until now, potato late blight is still the most serious threat to potato growth and has caused significant economic losses worldwide. Melatonin can induce plant innate immunity against pathogen infection, but the direct effects of melatonin on plant pathogens are poorly understood. In this study, we investigated the direct effects of melatonin on P. infestans. Exogenous melatonin significantly attenuated the potato late blight by inhibiting mycelial growth, changing cell ultrastructure, and reducing stress tolerance of P. infestans. Notably, synergistic anti-fungal effects of melatonin with fungicides on P. infestans suggest that melatonin could reduce the dose levels and enhance the efficacy of fungicide against potato late blight. A transcriptome analysis was carried out to mine downstream genes whose expression levels were affected by melatonin. The analysis of the transcriptome suggests that 66 differentially expressed genes involved in amino acid metabolic processes were significantly affected by melatonin. Moreover, the differentially expressed genes associated with stress tolerance, fungicide resistance, and virulence were also affected. These findings contribute to a new understanding of the direct functions of the melatonin on P. infestans and provide a potential ecofriendly biocontrol approach using a melatonin-based paradigm and application to prevent potato late blight.

  11. The tumor suppressor gene TRC8/RNF139 is disrupted by a constitutional balanced translocation t(8;22(q24.13;q11.21 in a young girl with dysgerminoma

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    Fiorio Patrizia

    2009-07-01

    Full Text Available Abstract Background RNF139/TRC8 is a potential tumor suppressor gene with similarity to PTCH, a tumor suppressor implicated in basal cell carcinomas and glioblastomas. TRC8 has the potential to act in a novel regulatory relationship linking the cholesterol/lipid biosynthetic pathway with cellular growth control and has been identified in families with hereditary renal (RCC and thyroid cancers. Haploinsufficiency of TRC8 may facilitate development of clear cell-RCC in association with VHL mutations, and may increase risk for other tumor types. We report a paternally inherited balanced translocation t(8;22 in a proposita with dysgerminoma. Methods The translocation was characterized by FISH and the breakpoints cloned, sequenced, and compared. DNA isolated from normal and tumor cells was checked for abnormalities by array-CGH. Expression of genes TRC8 and TSN was tested both on dysgerminoma and in the proposita and her father. Results The breakpoints of the translocation are located within the LCR-B low copy repeat on chromosome 22q11.21, containing the palindromic AT-rich repeat (PATRR involved in recurrent and non-recurrent translocations, and in an AT-rich sequence inside intron 1 of the TRC8 tumor-suppressor gene at 8q24.13. TRC8 was strongly underexpressed in the dysgerminoma. Translin is underexpressed in the dysgerminoma compared to normal ovary. TRC8 is a target of Translin (TSN, a posttranscriptional regulator of genes transcribed by the transcription factor CREM-tau in postmeiotic male germ cells. Conclusion A role for TRC8 in dysgerminoma may relate to its interaction with Translin. We propose a model in which one copy of TRC8 is disrupted by a palindrome-mediated translocation followed by complete loss of expression through suppression, possibly mediated by miRNA.

  12. Internal disruption in tokamaks

    International Nuclear Information System (INIS)

    Kuvshinov, B.N.; Savrukhin, P.V.

    1990-01-01

    A review of results of experimental and theoretical investigations of internal disruption in tokamaks is given. Specific features of various types of saw-tooth oscillations are described and their classification is performed. Theoretical models of the process of development of internal disruption instability are discussed. Effect of internal disruption on parameters of plasma, confined in tokamak, is considered. Scalings of period and amplitude of saw-tooth oscillations, as well as version radius are presented. Different methods for stabilizing instability of internal disruption are described

  13. Internal disruptions in tokamaks

    International Nuclear Information System (INIS)

    Kuvshinov, B.N.; Savrukhin, P.V.

    1990-01-01

    Experimental and theoretical studies of the phenomenon of internal disruptions in tokamaks are reviewed. A classification scheme is introduced and the features of different types of sawtooth oscillations are described. A theoretical model for the development of the internal disruption instability is discussed. The effect of internal disruptions on the parameters of plasma confined in tokamaks is discussed. Scaling laws for the period and amplitude of sawtooth oscillations, as well as for the inversion radius, are presented. Different methods of stabilizing the internal disruption instability are described

  14. Disruption of Mouse Cytochrome P450 4f14 (Cyp4f14 Gene) Causes Severe Perturbations in Vitamin E Metabolism*

    Science.gov (United States)

    Bardowell, Sabrina A.; Duan, Faping; Manor, Danny; Swanson, Joy E.; Parker, Robert S.

    2012-01-01

    Vitamin E is a family of naturally occurring and structurally related lipophilic antioxidants, one of which, α-tocopherol (α-TOH), selectively accumulates in vertebrate tissues. The ω-hydroxylase cytochrome P450–4F2 (CYP4F2) is the only human enzyme shown to metabolize vitamin E. Using cDNA cloning, cell culture expression, and activity assays, we identified Cyp4f14 as a functional murine ortholog of CYP4F2. We then investigated the effect of Cyp4f14 deletion on vitamin E metabolism and status in vivo. Cyp4f14-null mice exhibited substrate-specific reductions in liver microsomal vitamin E-ω-hydroxylase activity ranging from 93% (γ-TOH) to 48% (γ-tocotrienol). In vivo data obtained from metabolic cage studies showed whole-body reductions in metabolism of γ-TOH of 90% and of 68% for δ- and α-TOH. This metabolic deficit in Cyp4f14−/− mice was partially offset by increased fecal excretion of nonmetabolized tocopherols and of novel ω-1- and ω-2-hydroxytocopherols. 12′-OH-γ-TOH represented 41% of whole-body production of γ-TOH metabolites in Cyp4f14−/− mice fed a soybean oil diet. Despite these counterbalancing mechanisms, Cyp4f14-null mice fed this diet for 6 weeks hyper-accumulated γ-TOH (2-fold increase over wild-type littermates) in all tissues and appeared normal. We conclude that CYP4F14 is the major but not the only vitamin E-ω-hydroxylase in mice. Its disruption significantly impairs whole-body vitamin E metabolism and alters the widely conserved phenotype of preferential tissue deposition of α-TOH. This model animal and its derivatives will be valuable in determining the biological actions of specific tocopherols and tocotrienols in vivo. PMID:22665481

  15. Endocrine disrupting chemicals (bisphenol A, 4-nonylphenol, 4-tert-octylphenol) modulate expression of two distinct cytochrome P450 aromatase genes differently in gender types of the hermaphroditic fish Rivulus marmoratus.

    Science.gov (United States)

    Lee, Young-Mi; Seo, Jung Soo; Kim, Il-Chan; Yoon, Yong-Dal; Lee, Jae-Seong

    2006-06-30

    To understand the effect of endocrine-disrupting chemicals (EDCs) on cytochrome P450 aromatase (rm-cyp19) gene expression between gender types in the hermaphroditic fish Rivulus marmoratus, we cloned two distinct rm-cyp19 genes using RT-PCR with degenerative primers, obtained full-length cDNAs using 5'- and 3'-RACE-PCR methods, and completely sequenced them. The brain aromatase (rm-cyp19b) cDNA consisted of 2,124 bp including the open reading frame (ORF), which encoded a putative protein of 505 amino acids. The ovarian aromatase (rm-cyp19a) cDNA consisted of 2,075 bp, including the ORF encoding a putative protein of 516 amino acids. Expression patterns of rm-cyp19b and rm-cyp19a mRNAs were investigated in embryos of different developmental stages and in seven different tissues of adult fish. The rm-cyp19b gene in hermaphrodite and secondary male R. marmoratus was predominantly expressed in the brain, while the rm-cyp19a gene was expressed gender-specifically in the gonad. The expression of rm-cyp19b mRNA increased from stage 1 (2 d post fertilization) to stage 4 (12 d post fertilization) in a developmental stage-dependent manner but steeply decreased in the hatching stage. Compared to the rm-cyp19b gene, the abundance of ovarian aromatase rm-cyp19a transcripts was very low, and its expression was first detected at stage 3 and then decreased gradually to the hatching stage. Alteration of rm-cyp19b and rm-cyp19a gene expression was further analyzed in the brain and gonad by real-time RT-PCR 96 h after EDC exposure in hermaphrodites and secondary males. The brain aromatase rm-cyp19b gene was up-regulated in the brain after 4-nonylphenol (4-NP)-exposure, while the ovarian aromatase rm-cyp19a gene was significantly down-regulated in the gonad. In 300 microg/L 4-tert octylphenol (4-tert-OP), or 600 microg/L bisphenol A-exposed brain and gonad, both rm-cyp19b and rm-cyp19a genes were up-regulated. In the case of secondary males, the rm-cyp19b gene was highly expressed in

  16. Potent Nematicidal Activity and New Hybrid Metabolite Production by Disruption of a Cytochrome P450 Gene Involved in the Biosynthesis of Morphological Regulatory Arthrosporols in Nematode-Trapping Fungus Arthrobotrys oligospora.

    Science.gov (United States)

    Song, Tian-Yang; Xu, Zi-Fei; Chen, Yong-Hong; Ding, Qiu-Yan; Sun, Yu-Rong; Miao, Yang; Zhang, Ke-Qin; Niu, Xue-Mei

    2017-05-24

    Types of polyketide synthase-terpenoid synthase (PKS-TPS) hybrid metabolites, including arthrosporols with significant morphological regulatory activity, have been elucidated from nematode-trapping fungus Arthrobotrys oligospora. A previous study suggested that the gene cluster AOL_s00215 in A. oligospora was involved in the production of arthrosporols. Here, we report that disruption of one cytochrome P450 monooxygenase gene AOL_s00215g280 in the cluster resulted in significant phenotypic difference and much aerial hyphae. A further bioassay indicated that the mutant showed a dramatic decrease in the conidial formation but developed numerous traps and killed 85% nematodes within 6 h in contact with prey, in sharp contrast to the wild-type strain with no obvious response. Chemical investigation revealed huge accumulation of three new PKS-TPS epoxycyclohexone derivatives with different oxygenated patterns around the epoxycyclohexone moiety and the absence of arthrosporols in the cultural broth of the mutant ΔAOL_s00215g280. These findings suggested that a study on the biosynthetic pathway for morphological regulatory metabolites in nematode-trapping fungus would provide an efficient way to develop new fungal biocontrol agents.

  17. Disruption of NBS1 gene leads to early embryonic lethality in homozygous null mice and induces specific cancer in heterozygous mice

    Energy Technology Data Exchange (ETDEWEB)

    Kurimasa, Akihiro; Burma, Sandeep; Henrie, Melinda; Ouyang, Honghai; Osaki, Mitsuhiko; Ito, Hisao; Nagasawa, Hatsumi; Little, John B.; Oshimura, Mitsuo; Li, Gloria C.; Chen, David J.

    2002-04-15

    Nijmegen breakage syndrome (NBS) is a rare autosomal recessive chromosome instability syndrome characterized by microcephaly, growth retardation, immunodeficiency, and cancer predisposition, with cellular features similar to that of ataxia telangiectasia (AT). NBS results from mutations in the mammalian gene Nbs1 that codes for a 95-kDa protein called nibrin, NBS1, or p95. To establish an animal model for NBS, we attempted to generate NBS1 knockout mice. However, NBS1 gene knockouts were lethal at an early embryonic stage. NBS1 homozygous(-/-) blastocyst cells cultured in vitro showed retarded growth and subsequently underwent growth arrest within 5 days of culture. Apoptosis, assayed by TUNEL staining, was observed in NBSI homozygous(-/-) blastocyst cells cultured for four days. NBSI heterozygous(+/-) mice were normal, and exhibited no specific phenotype for at least one year. However, fibroblast cells from NBSI heterozygous(+/-) mice displayed an enhanced frequency of spontaneous transformation to anchorage-independent growth as compared to NBS1 wild-type(+/+) cells. Furthermore, heterozygous(+/-) mice exhibited a high incidence of hepatocellular carcinoma after one year compared to wild-type mice, even though no significant differences in the incidence of other tumors such as lung adenocarcinoma and lymphoma were observed. Taken together, these results strongly suggest that NBS1 heterozygosity and reduced NBSI expression induces formation of specific tumors in mice.

  18. Combination of hypomorphic mutations of the Drosophila homologues of aryl hydrocarbon receptor and nucleosome assembly protein family genes disrupts morphogenesis, memory and detoxification.

    Science.gov (United States)

    Kuzin, Boris A; Nikitina, Ekaterina A; Cherezov, Roman O; Vorontsova, Julia E; Slezinger, Mikhail S; Zatsepina, Olga G; Simonova, Olga B; Enikolopov, Grigori N; Savvateeva-Popova, Elena V

    2014-01-01

    Aryl hydrocarbon receptor is essential for biological responses to endogenous and exogenous toxins in mammals. Its Drosophila homolog spineless plays an important role in fly morphogenesis. We have previously shown that during morphogenesis spineless genetically interacts with CG5017 gene, which encodes a nucleosome assembly factor and may affect cognitive function of the fly. We now demonstrate synergistic interactions of spineless and CG5017 in pathways controlling oxidative stress response and long-term memory formation in Drosophila melanogaster. Oxidative stress was induced by low doses of X-ray irradiation of flies carrying hypomorphic mutation of spineless, mutation of CG5017, and their combination. To determine the sensitivity of these mutants to pharmacological modifiers of the irradiation effect, we irradiated flies growing on standard medium supplemented by radiosensitizer furazidin and radioprotector serotonin. The effects of irradiation were investigated by analyzing leg and antenna morphological structures and by using real-time PCR to measure mRNA expression levels for spineless, Cyp6g1 and Gst-theta genes. We also examined long-term memory in these mutants using conditioned courtship suppression paradigm. Our results show that the interaction of spineless and CG5017 is important for regulation of morphogenesis, long-term memory formation, and detoxification during oxidative stress. Since spineless and CG5017 are evolutionary conserved, these results must be considered when evaluating the risk of combining similar mutations in other organisms, including humans.

  19. Combination of hypomorphic mutations of the Drosophila homologues of aryl hydrocarbon receptor and nucleosome assembly protein family genes disrupts morphogenesis, memory and detoxification.

    Directory of Open Access Journals (Sweden)

    Boris A Kuzin

    Full Text Available Aryl hydrocarbon receptor is essential for biological responses to endogenous and exogenous toxins in mammals. Its Drosophila homolog spineless plays an important role in fly morphogenesis. We have previously shown that during morphogenesis spineless genetically interacts with CG5017 gene, which encodes a nucleosome assembly factor and may affect cognitive function of the fly. We now demonstrate synergistic interactions of spineless and CG5017 in pathways controlling oxidative stress response and long-term memory formation in Drosophila melanogaster. Oxidative stress was induced by low doses of X-ray irradiation of flies carrying hypomorphic mutation of spineless, mutation of CG5017, and their combination. To determine the sensitivity of these mutants to pharmacological modifiers of the irradiation effect, we irradiated flies growing on standard medium supplemented by radiosensitizer furazidin and radioprotector serotonin. The effects of irradiation were investigated by analyzing leg and antenna morphological structures and by using real-time PCR to measure mRNA expression levels for spineless, Cyp6g1 and Gst-theta genes. We also examined long-term memory in these mutants using conditioned courtship suppression paradigm. Our results show that the interaction of spineless and CG5017 is important for regulation of morphogenesis, long-term memory formation, and detoxification during oxidative stress. Since spineless and CG5017 are evolutionary conserved, these results must be considered when evaluating the risk of combining similar mutations in other organisms, including humans.

  20. Disruptions in JET

    International Nuclear Information System (INIS)

    Wesson, J.A.; Gill, R.D.; Hugon, M.

    1989-01-01

    In JET, both high density and low-q operation are limited by disruptions. The density limit disruptions are caused initially by impurity radiation. This causes a contraction of the plasma temperature profile and leads to an MHD unstable configuration. There is evidence of magnetic island formation resulting in minor disruptions. After several minor disruptions, a major disruption with a rapid energy quench occurs. This event takes place in two stages. In the first stage there is a loss of energy from the central region. In the second stage there is a more rapid drop to a very low temperature, apparently due to a dramatic increase in impurity radiation. The final current decay takes place in the resulting cold plasma. During the growth of the MHD instability the initially rotating mode is brought to rest. This mode locking is believed to be due to an electromagnetic interaction with the vacuum vessel and external magnetic field asymmetries. The low-q disruptions are remarkable for the precision with which they occur at q ψ = 2. These disruptions do not have extended precursors or minor disruptions. The instability grows and locks rapidly. The energy quench and current decay are generally similar to those of the density limit. (author). 43 refs, 35 figs, 3 tabs

  1. The secretion, synthesis, and metabolism of cortisol and its downstream genes in the H-P-I axis of rare minnows (Gobiocypris rarus) are disrupted by acute waterborne cadmium exposure.

    Science.gov (United States)

    Liu, Xiao-Hong; Xie, Bi-Wen; Wang, Zhi-Jian; Jin, Li; Zhang, Yao-Guang

    2016-01-01

    The H (hypothalamic)-P (pituitary)-I (interrenal) axis plays a critical role in the fish stress response and is regulated by several factors. Cadmium (Cd) is one of the most toxic heavy metals in the world, but its effects on the H-P-I axis of teleosts are largely unknown. Using rare minnow (Gobiocypris rarus) as an experimental animal, we found that Cd only disrupted the secretion and synthesis of cortisol. Neither hormones at the H or P level nor the expressions of their receptor genes (corticotropin-releasing hormone receptor (CRHR) and melanocortin receptor 2 (MC2R)) were affected. Steroidogenic acute regulator (StAR), CYP11A1 and CYP11B1, which encode the key enzymes in the cortisol synthesis pathway, were significantly up-regulated in the kidney (including the head kidney). The level of 11β-HSD2, which is required for the conversion of cortisol to cortisone, was increased in the kidney, intestine, brain, and hepatopancreas, whereas the expression of 11β-HSD1, which encodes the reverse conversion enzyme, was increased in the gill, kidney and almost unchanged in other tissues. The enzyme activity concentration of 11β-HSD2 was increased in the kidney as well. The level of glucocorticoid receptor (GR) decreased in the intestine, gill and muscle, and the key GR regulator FK506 binding protein5 (FKBP5) was up-regulated in the GR-decreased tissues, whereas the level of nuclear receptor co-repressor 1 (NCoR1), another GR regulator remained almost unchanged. Thus, GR, FKBP5 and 11β-HSD2 may be involved in Cd-induced cortisol disruption. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Obesity in aging exacerbates blood-brain barrier disruption, neuroinflammation, and oxidative stress in the mouse hippocampus: effects on expression of genes involved in beta-amyloid generation and Alzheimer's disease.

    Science.gov (United States)

    Tucsek, Zsuzsanna; Toth, Peter; Sosnowska, Danuta; Gautam, Tripti; Mitschelen, Matthew; Koller, Akos; Szalai, Gabor; Sonntag, William E; Ungvari, Zoltan; Csiszar, Anna

    2014-10-01

    There is growing evidence that obesity has deleterious effects on the brain and cognitive function in the elderly population. However, the specific mechanisms through which aging and obesity interact to promote cognitive decline remain unclear. To test the hypothesis that aging exacerbates obesity-induced cerebromicrovascular damage and neuroinflammation, we compared young (7 months) and aged (24 months) high fat diet-fed obese C57BL/6 mice. Aging exacerbated obesity-induced systemic inflammation and blood-brain barrier disruption, as indicated by the increased circulating levels of proinflammatory cytokines and increased presence of extravasated immunoglobulin G in the hippocampus, respectively. Obesity-induced blood-brain barrier damage was associated with microglia activation, upregulation of activating Fc-gamma receptors and proinflammatory cytokines, and increased oxidative stress. Treatment of cultured primary microglia with sera derived from aged obese mice resulted in significantly more pronounced microglia activation and oxidative stress, as compared with treatment with young sera. Serum-induced activation and oxidative stress were also exacerbated in primary microglia derived from aged animals. Hippocampal expression of genes involved in regulation of the cellular amyloid precursor protein-dependent signaling pathways, beta-amyloid generation, and the pathogenesis of tauopathy were largely unaffected by obesity in aged mice. Collectively, obesity in aging is associated with a heightened state of systemic inflammation, which exacerbates blood-brain barrier disruption. The resulting neuroinflammation and oxidative stress in the mouse hippocampus likely contribute to the significant cognitive decline observed in aged obese animals. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Tritiated water exposure disrupts myofibril structure and induces mis-regulation of eye opacity and DNA repair genes in zebrafish early life stages.

    Science.gov (United States)

    Arcanjo, Caroline; Armant, Olivier; Floriani, Magali; Cavalie, Isabelle; Camilleri, Virginie; Simon, Olivier; Orjollet, Daniel; Adam-Guillermin, Christelle; Gagnaire, Béatrice

    2018-04-27

    Tritium ( 3 H) is a radioactive isotope of hydrogen. In the environment, the most common form of tritium is tritiated water (HTO). The present study aimed to identify early biomarkers of HTO contamination through the use of an aquatic model, the zebrafish (Danio rerio). We used the zebrafish embryo-larvae model to investigate the modes of action of HTO exposure at dose rates of 0.4 and 4 mGy/h, dose rates expected to induce deleterious effects on fish. Zebrafish were exposed to HTO from 3 hpf (hours post fertilization) to 96 hpf. The transcriptomic effects were investigated 24 h and 96 h after the beginning of the contamination, using mRNAseq. Results suggested an impact of HTO contamination, regardless of the dose rate, on genes involved in muscle contraction (tnnt2d, tnni2a.4, slc6a1a or atp2a1l) and eye opacity (crygm2d9, crygmxl1, mipb or lim2.3) after 24 h of contamination. Interestingly, an opposite differential expression was highlighted in genes playing a role in muscle contraction and eye opacity in 24 hpf embryos when comparing dose rates, suggesting an onset of DNA protective mechanisms. The expression of h2afx and ddb2 involved in DNA repair was enhanced in response to HTO exposure. The entrainment of circadian clock and the response to H 2 O 2 signalling pathways were enriched at 96 hpf at 0.4 mGy/h and in both stages after 4 mGy/h. Genes involved in ROS scavenging were differentially expressed only after 24 h of exposure for the lowest dose rate, suggesting the onset of early protective mechanisms against oxidative stress. Effects highlighted on muscle at the molecular scale were confirmed at a higher biological scale, as electron microscopy observations revealed sarcomere impairments in 96 hpf larvae for both dose rates. Together with other studies, the present work provides useful data to better understand modes of action of tritium on zebrafish embryos-larvae. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Disruptions in Tokamaks

    International Nuclear Information System (INIS)

    Bondeson, A.

    1987-01-01

    This paper discusses major and minor disruptions in Tokamaks. A number of models and numerical simulations of disruptions based on resistive MHD are reviewed. A discussion is given of how disruptive current profiles are correlated with the experimentally known operational limits in density and current. It is argued that the q a =2 limit is connected with stabilization of the m=2/n=1 tearing mode for a approx.< 2.7 by resistive walls and mode rotation. Experimental and theoretical observations indicate that major disruptions usually occur in at least two phases, first a 'predisruption', or loss of confinement in the region 1 < q < 2, leaving the q approx.= 1 region almost unaffected, followed by a final disruption of the central part, interpreted here as a toroidal n = 1 external kink mode. (author)

  5. Disrupting the cinnamyl alcohol dehydrogenase 1 gene (BdCAD1) leads to altered lignification and improved saccharification in Brachypodium distachyon.

    Science.gov (United States)

    Bouvier d'Yvoire, Madeleine; Bouchabke-Coussa, Oumaya; Voorend, Wannes; Antelme, Sébastien; Cézard, Laurent; Legée, Frédéric; Lebris, Philippe; Legay, Sylvain; Whitehead, Caragh; McQueen-Mason, Simon J; Gomez, Leonardo D; Jouanin, Lise; Lapierre, Catherine; Sibout, Richard

    2013-02-01

    Brachypodium distachyon (Brachypodium) has been proposed as a model for grasses, but there is limited knowledge regarding its lignins and no data on lignin-related mutants. The cinnamyl alcohol dehydrogenase (CAD) genes involved in lignification are promising targets to improve the cellulose-to-ethanol conversion process. Down-regulation of CAD often induces a reddish coloration of lignified tissues. Based on this observation, we screened a chemically induced population of Brachypodium mutants (Bd21-3 background) for red culm coloration. We identified two mutants (Bd4179 and Bd7591), with mutations in the BdCAD1 gene. The mature stems of these mutants displayed reduced CAD activity and lower lignin content. Their lignins were enriched in 8-O-4- and 4-O-5-coupled sinapaldehyde units, as well as resistant inter-unit bonds and free phenolic groups. By contrast, there was no increase in coniferaldehyde end groups. Moreover, the amount of sinapic acid ester-linked to cell walls was measured for the first time in a lignin-related CAD grass mutant. Functional complementation of the Bd4179 mutant with the wild-type BdCAD1 allele restored the wild-type phenotype and lignification. Saccharification assays revealed that Bd4179 and Bd7591 lines were more susceptible to enzymatic hydrolysis than wild-type plants. Here, we have demonstrated that BdCAD1 is involved in lignification of Brachypodium. We have shown that a single nucleotide change in BdCAD1 reduces the lignin level and increases the degree of branching of lignins through incorporation of sinapaldehyde. These changes make saccharification of cells walls pre-treated with alkaline easier without compromising plant growth. © 2012 The Authors The Plant Journal © 2012 Blackwell Publishing Ltd.

  6. Silencing of HaAce1 gene by host-delivered artificial microRNA disrupts growth and development of Helicoverpa armigera.

    Science.gov (United States)

    Saini, Ravi Prakash; Raman, Venkat; Dhandapani, Gurusamy; Malhotra, Era Vaidya; Sreevathsa, Rohini; Kumar, Polumetla Ananda; Sharma, Tilak R; Pattanayak, Debasis

    2018-01-01

    The polyphagous insect-pest, Helicoverpa armigera, is a serious threat to a number of economically important crops. Chemical application and/or cultivation of Bt transgenic crops are the two strategies available now for insect-pest management. However, environmental pollution and long-term sustainability are major concerns against these two options. RNAi is now considered as a promising technology to complement Bt to tackle insect-pests menace. In this study, we report host-delivered silencing of HaAce1 gene, encoding the predominant isoform of H. armigera acetylcholinesterase, by an artificial microRNA, HaAce1-amiR1. Arabidopsis pre-miRNA164b was modified by replacing miR164b/miR164b* sequences with HaAce1-amiR1/HaAce1-amiR1* sequences. The recombinant HaAce1-preamiRNA1 was put under the control of CaMV 35S promoter and NOS terminator of plant binary vector pBI121, and the resultant vector cassette was used for tobacco transformation. Two transgenic tobacco lines expressing HaAce1-amiR1 was used for detached leaf insect feeding bioassays. Larval mortality of 25% and adult deformity of 20% were observed in transgenic treated insect group over that control tobacco treated insect group. The reduction in the steady-state level of HaAce1 mRNA was 70-80% in the defective adults compared to control. Our results demonstrate promise for host-delivered amiRNA-mediated silencing of HaAce1 gene for H. armigera management.

  7. Mining of biomarker genes from expressed sequence tags and differential display reverse transcriptase-polymerase chain reaction in the self-fertilizing fish, Kryptolebias marmoratus and their expression patterns in response to exposure to an endocrine-disrupting alkylphenol, bisphenol A.

    Science.gov (United States)

    Lee, Young-Mi; Rhee, Jae-Sung; Hwang, Dae-Sik; Kim, Il-Chan; Raisuddin, Sheikh; Lee, Jae-Seong

    2007-06-30

    Expressed sequence tags (ESTs) and differentially expressed cDNAs from the self-fertilizing fish, Kryptolebias marmoratus were mined to develop alternative biomarkers for endocrine-disrupting chemicals (EDCs). 1,577 K. marmoratus cDNA clones were randomly sequenced from the 5'-end. These clones corresponded to 1,518 and 1,519 genes in medaka dbEST and zebrafish dbEST, respectively. Of the matched genes, 197 and 115 genes obtained Unigene IDs in medaka dbEST and zebrafish dbEST, respectively. Many of the annotated genes are potential biomarkers for environmental stresses. In a differential display reverse transcriptase-polymerase chain reaction (DD RT-PCR) study, 56 differential expressed genes were obtained from fish liver exposed to bisphenol A. Of these, 16 genes were identified after BLAST search to GenBank, and the annotated genes were mainly involved in catalytic activity and binding. The expression patterns of these 16 genes were validated by real-time RT-PCR of liver tissue from fish exposed to bisphenol A. Our findings suggest that expression of these 16 genes is modulated by endocrine disrupting chemicals, and therefore that they are potential biomarkers for environmental stress including EDCs exposure.

  8. Immunization by intrabronchial administration to 1-week-old foals of an unmarked double gene disruption strain of Rhodococcus equi strain 103+.

    Science.gov (United States)

    Pei, Yanlong; Nicholson, Vivian; Woods, Katharine; Prescott, John F

    2007-11-15

    Rhodococcus equi causes fatal granulomatous pneumonia in foals and immunocompromised animals and humans. However, there is no effective vaccine against this infection. In this study, the chromosomal genes isocitrate lyase (icl) and cholesterol oxidase (choE) were chosen as targets for mutation and assessment of the double mutant as an intrabronchial vaccine in 1-week-old foals. Using a modification of a suicide plasmid previously developed in this laboratory, we developed a choE-icl unmarked deletion mutant of R. equi strain 103+. Five 1-week-old foals were infected intrabronchially with the mutant and challenged intrabronchially with the parent, virulent, strain 2 weeks later. Three of the foals were protected against pneumonia caused by the virulent strain, but the other two foals developed pneumonia caused by the mutant strain during the post-challenge period. Since infection of 3-week-old foals by an icl mutant in an earlier study had shown complete attenuation of the strain, we conclude that a proportion of foals in the 1st week or so of life are predisposed to developing R. equi pneumonia because of an inability to mount an effective immune response. This has been suspected previously but this is the first time that this has been demonstrated experimentally.

  9. Targeted disruption of the Mast syndrome gene SPG21 in mice impairs hind limb function and alters axon branching in cultured cortical neurons

    Science.gov (United States)

    Soderblom, Cynthia; Stadler, Julia; Jupille, Henri; Blackstone, Craig; Shupliakov, Oleg

    2017-01-01

    Mast syndrome (SPG21) is a childhood-onset, autosomal recessive, complicated form of hereditary spastic paraplegia (HSP) characterized by dementia, thin corpus callosum, white matter abnormalities, and cerebellar and extrapyramidal signs in addition to spastic paraparesis. A nucleotide insertion resulting in premature truncation of the SPG21 gene product maspardin underlies this disorder, likely leading to loss of protein function. In this study, we generated SPG21−/− knockout mice by homologous recombination as a possible animal model for SPG21. Though SPG21−/− mice appeared normal at birth, within several months they developed gradually progressive hind limb dysfunction. Cerebral cortical neurons cultured from SPG21−/− mice exhibited significantly more axonal branching than neurons from wild-type animals, while comprehensive neuropathological analysis of SPG21−/− mice did not reveal definitive abnormalities. Since alterations in axon branching have been seen in neurons derived from animal models of other forms of HSP as well as motor neuron diseases, this may represent a common cellular pathogenic theme. PMID:20661613

  10. Role of alpha2C-adrenoceptor subtype in spatial working memory as revealed by mice with targeted disruption of the alpha2C-adrenoceptor gene.

    Science.gov (United States)

    Tanila, H; Mustonen, K; Sallinen, J; Scheinin, M; Riekkinen, P

    1999-02-01

    The role of the alpha2C-adrenoceptor subtype in mediating the beneficial effect of alpha2-adrenoceptor agonists on spatial working memory was studied in adult mice with targeted inactivation of the alpha2C-receptor gene (KO) and their wild-type controls (WT). A delayed alternation task was run in a T-maze with mixed delays varying from 20 s to 120 s. Dexmedetomidine, a specific but subtype nonselective alpha2-adrenoceptor agonist, dose-dependently decreased the total number of errors. The effect was strongest at the dose of 5 microg/kg (s.c.), and was observed similarly in KO and WT mice. KO mice performed inferior to WT mice due to a higher number of perseverative errors. Dexmedetomidine slowed initiation of the motor response in the start phase at lower doses in WT mice than in KO mice but no such difference was observed in the return phase of the task, suggesting involvement of alpha2C-adrenoceptors in the cognitive aspect of response preparation or in response sequence initiation. According to these findings, enhancement of spatial working memory is best achieved with alpha2-adrenoceptor agonists which have neither agonistic nor antagonistic effects at the alpha2C-adrenoceptor subtype.

  11. Haploinsufficiency of the 22q11.2 microdeletion gene Mrpl40 disrupts short-term synaptic plasticity and working memory through dysregulation of mitochondrial calcium.

    Science.gov (United States)

    Devaraju, P; Yu, J; Eddins, D; Mellado-Lagarde, M M; Earls, L R; Westmoreland, J J; Quarato, G; Green, D R; Zakharenko, S S

    2017-09-01

    Hemizygous deletion of a 1.5- to 3-megabase region on chromosome 22 causes 22q11.2 deletion syndrome (22q11DS), which constitutes one of the strongest genetic risks for schizophrenia. Mouse models of 22q11DS have abnormal short-term synaptic plasticity that contributes to working-memory deficiencies similar to those in schizophrenia. We screened mutant mice carrying hemizygous deletions of 22q11DS genes and identified haploinsufficiency of Mrpl40 (mitochondrial large ribosomal subunit protein 40) as a contributor to abnormal short-term potentiation (STP), a major form of short-term synaptic plasticity. Two-photon imaging of the genetically encoded fluorescent calcium indicator GCaMP6, expressed in presynaptic cytosol or mitochondria, showed that Mrpl40 haploinsufficiency deregulates STP via impaired calcium extrusion from the mitochondrial matrix through the mitochondrial permeability transition pore. This led to abnormally high cytosolic calcium transients in presynaptic terminals and deficient working memory but did not affect long-term spatial memory. Thus, we propose that mitochondrial calcium deregulation is a novel pathogenic mechanism of cognitive deficiencies in schizophrenia.

  12. Understanding disruptions in tokamaksa)

    Science.gov (United States)

    Zakharov, Leonid E.; Galkin, Sergei A.; Gerasimov, Sergei N.; contributors, JET-EFDA

    2012-05-01

    This paper describes progress achieved since 2007 in understanding disruptions in tokamaks, when the effect of plasma current sharing with the wall was introduced into theory. As a result, the toroidal asymmetry of the plasma current measurements during vertical disruption event (VDE) on the Joint European Torus was explained. A new kind of plasma equilibria and mode coupling was introduced into theory, which can explain the duration of the external kink 1/1 mode during VDE. The paper presents first results of numerical simulations using a free boundary plasma model, relevant to disruptions.

  13. Disruptive Mood Dysregulation Disorder

    Science.gov (United States)

    ... Application Process Managing Grants Clinical Research Training Small Business Research Labs at NIMH Labs at NIMH Home Research ... Chat on Disruptive Mood Dysregulation Disorder (Archived Transcript) Research and ... Journal Articles: References and abstracts from MEDLINE/PubMed (National ...

  14. Disruption Rose Tinted II

    OpenAIRE

    Livingstone, Andrew

    2009-01-01

    'Disruption - Rose Tinted II' continues to engage narratives of historical English china as previously explored in the work 'Rose Tinted'. This work engages the sleepy rural idyll which is overlaid with visual contemporary social commentary.

  15. Effects of disrupting the polyketide synthase gene WdPKS1 in Wangiella [Exophiala] dermatitidis on melanin production and resistance to killing by antifungal compounds, enzymatic degradation, and extremes in temperature

    Directory of Open Access Journals (Sweden)

    Mandal Piyali

    2006-06-01

    Full Text Available Abstract Background Wangiella dermatitidis is a human pathogenic fungus that is an etiologic agent of phaeohyphomycosis. W. dermatitidis produces a black pigment that has been identified as a dihydroxynaphthalene melanin and the production of this pigment is associated with its virulence. Cell wall pigmentation in W. dermatitidis depends on the WdPKS1 gene, which encodes a polyketide synthase required for generating the key precursor for dihydroxynaphthalene melanin biosynthesis. Results We analyzed the effects of disrupting WdPKS1 on dihydroxynaphthalene melanin production and resistance to antifungal compounds. Transmission electron microscopy revealed that wdpks1Δ-1 yeast had thinner cell walls that lacked an electron-opaque layer compared to wild-type cells. However, digestion of the wdpks1Δ-1 yeast revealed small black particles that were consistent with a melanin-like compound, because they were acid-resistant, reacted with melanin-binding antibody, and demonstrated a free radical signature by electron spin resonance analysis. Despite lacking the WdPKS1 gene, the mutant yeast were capable of catalyzing the formation of melanin from L-3,4-dihyroxyphenylalanine. The wdpks1Δ-1 cells were significantly more susceptible to killing by voriconazole, amphotericin B, NP-1 [a microbicidal peptide], heat and cold, and lysing enzymes than the heavily melanized parental or complemented strains. Conclusion In summary, W. dermatitidis makes WdPKS-dependent and -independent melanins, and the WdPKS1-dependent deposition of melanin in the cell wall confers protection against antifungal agents and environmental stresses. The biological role of the WdPKS-independent melanin remains unclear.

  16. Digital disruption ?syndromes.

    Science.gov (United States)

    Sullivan, Clair; Staib, Andrew

    2017-05-18

    The digital transformation of hospitals in Australia is occurring rapidly in order to facilitate innovation and improve efficiency. Rapid transformation can cause temporary disruption of hospital workflows and staff as processes are adapted to the new digital workflows. The aim of this paper is to outline various types of digital disruption and some strategies for effective management. A large tertiary university hospital recently underwent a rapid, successful roll-out of an integrated electronic medical record (EMR). We observed this transformation and propose several digital disruption "syndromes" to assist with understanding and management during digital transformation: digital deceleration, digital transparency, digital hypervigilance, data discordance, digital churn and post-digital 'depression'. These 'syndromes' are defined and discussed in detail. Successful management of this temporary digital disruption is important to ensure a successful transition to a digital platform. What is known about this topic? Digital disruption is defined as the changes facilitated by digital technologies that occur at a pace and magnitude that disrupt established ways of value creation, social interactions, doing business and more generally our thinking. Increasing numbers of Australian hospitals are implementing digital solutions to replace traditional paper-based systems for patient care in order to create opportunities for improved care and efficiencies. Such large scale change has the potential to create transient disruption to workflows and staff. Managing this temporary disruption effectively is an important factor in the successful implementation of an EMR. What does this paper add? A large tertiary university hospital recently underwent a successful rapid roll-out of an integrated electronic medical record (EMR) to become Australia's largest digital hospital over a 3-week period. We observed and assisted with the management of several cultural, behavioural and

  17. Search and Disrupt

    DEFF Research Database (Denmark)

    Ørding Olsen, Anders

    . However, incumbent sources engaged in capability reconfiguration to accommodate disruption improve search efforts in disruptive technologies. The paper concludes that the value of external sources is contingent on more than their knowledge. Specifically, interdependence of sources in search gives rise...... to influence from individual strategic interests on the outcomes. More generally, this points to the need for understanding the two-way influence of sources, rather than viewing external search as one-way knowledge accessing....

  18. Disruption prediction at JET

    International Nuclear Information System (INIS)

    Milani, F.

    1998-12-01

    The sudden loss of the plasma magnetic confinement, known as disruption, is one of the major issue in a nuclear fusion machine as JET (Joint European Torus). Disruptions pose very serious problems to the safety of the machine. The energy stored in the plasma is released to the machine structure in few milliseconds resulting in forces that at JET reach several Mega Newtons. The problem is even more severe in the nuclear fusion power station where the forces are in the order of one hundred Mega Newtons. The events that occur during a disruption are still not well understood even if some mechanisms that can lead to a disruption have been identified and can be used to predict them. Unfortunately it is always a combination of these events that generates a disruption and therefore it is not possible to use simple algorithms to predict it. This thesis analyses the possibility of using neural network algorithms to predict plasma disruptions in real time. This involves the determination of plasma parameters every few milliseconds. A plasma boundary reconstruction algorithm, XLOC, has been developed in collaboration with Dr. D. O'Brien and Dr. J. Ellis capable of determining the plasma wall/distance every 2 milliseconds. The XLOC output has been used to develop a multilayer perceptron network to determine plasma parameters as l i and q ψ with which a machine operational space has been experimentally defined. If the limits of this operational space are breached the disruption probability increases considerably. Another approach for prediction disruptions is to use neural network classification methods to define the JET operational space. Two methods have been studied. The first method uses a multilayer perceptron network with softmax activation function for the output layer. This method can be used for classifying the input patterns in various classes. In this case the plasma input patterns have been divided between disrupting and safe patterns, giving the possibility of

  19. Disruption of Ttll5/stamp gene (tubulin tyrosine ligase-like protein 5/SRC-1 and TIF2-associated modulatory protein gene) in male mice causes sperm malformation and infertility.

    Science.gov (United States)

    Lee, Geun-Shik; He, Yuanzheng; Dougherty, Edward J; Jimenez-Movilla, Maria; Avella, Matteo; Grullon, Sean; Sharlin, David S; Guo, Chunhua; Blackford, John A; Awasthi, Smita; Zhang, Zhenhuan; Armstrong, Stephen P; London, Edra C; Chen, Weiping; Dean, Jurrien; Simons, S Stoney

    2013-05-24

    TTLL5/STAMP (tubulin tyrosine ligase-like family member 5) has multiple activities in cells. TTLL5 is one of 13 TTLLs, has polyglutamylation activity, augments the activity of p160 coactivators (SRC-1 and TIF2) in glucocorticoid receptor-regulated gene induction and repression, and displays steroid-independent growth activity with several cell types. To examine TTLL5/STAMP functions in whole animals, mice were prepared with an internal deletion that eliminated several activities of the Stamp gene. This mutation causes both reduced levels of STAMP mRNA and C-terminal truncation of STAMP protein. Homozygous targeted mutant (Stamp(tm/tm)) mice appear normal except for marked decreases in male fertility associated with defects in progressive sperm motility. Abnormal axonemal structures with loss of tubulin doublets occur in most Stamp(tm/tm) sperm tails in conjunction with substantial reduction in α-tubulin polyglutamylation, which closely correlates with the reduction in mutant STAMP mRNA. The axonemes in other structures appear unaffected. There is no obvious change in the organs for sperm development of WT versus Stamp(tm/tm) males despite the levels of WT STAMP mRNA in testes being 20-fold higher than in any other organ examined. This defect in male fertility is unrelated to other Ttll genes or 24 genes previously identified as important for sperm function. Thus, STAMP appears to participate in a unique, tissue-selective TTLL-mediated pathway for α-tubulin polyglutamylation that is required for sperm maturation and motility and may be relevant for male fertility.

  20. Disruption of Ttll5/Stamp Gene (Tubulin Tyrosine Ligase-like Protein 5/SRC-1 and TIF2-associated Modulatory Protein Gene) in Male Mice Causes Sperm Malformation and Infertility*

    Science.gov (United States)

    Lee, Geun-Shik; He, Yuanzheng; Dougherty, Edward J.; Jimenez-Movilla, Maria; Avella, Matteo; Grullon, Sean; Sharlin, David S.; Guo, Chunhua; Blackford, John A.; Awasthi, Smita; Zhang, Zhenhuan; Armstrong, Stephen P.; London, Edra C.; Chen, Weiping; Dean, Jurrien; Simons, S. Stoney

    2013-01-01

    TTLL5/STAMP (tubulin tyrosine ligase-like family member 5) has multiple activities in cells. TTLL5 is one of 13 TTLLs, has polyglutamylation activity, augments the activity of p160 coactivators (SRC-1 and TIF2) in glucocorticoid receptor-regulated gene induction and repression, and displays steroid-independent growth activity with several cell types. To examine TTLL5/STAMP functions in whole animals, mice were prepared with an internal deletion that eliminated several activities of the Stamp gene. This mutation causes both reduced levels of STAMP mRNA and C-terminal truncation of STAMP protein. Homozygous targeted mutant (Stamptm/tm) mice appear normal except for marked decreases in male fertility associated with defects in progressive sperm motility. Abnormal axonemal structures with loss of tubulin doublets occur in most Stamptm/tm sperm tails in conjunction with substantial reduction in α-tubulin polyglutamylation, which closely correlates with the reduction in mutant STAMP mRNA. The axonemes in other structures appear unaffected. There is no obvious change in the organs for sperm development of WT versus Stamptm/tm males despite the levels of WT STAMP mRNA in testes being 20-fold higher than in any other organ examined. This defect in male fertility is unrelated to other Ttll genes or 24 genes previously identified as important for sperm function. Thus, STAMP appears to participate in a unique, tissue-selective TTLL-mediated pathway for α-tubulin polyglutamylation that is required for sperm maturation and motility and may be relevant for male fertility. PMID:23558686

  1. Gene

    Data.gov (United States)

    U.S. Department of Health & Human Services — Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes,...

  2. The disruption management model.

    Science.gov (United States)

    McAlister, James

    2011-10-01

    Within all organisations, business continuity disruptions present a set of dilemmas that managers may not have dealt with before in their normal daily duties. The disruption management model provides a simple but effective management tool to enable crisis management teams to stay focused on recovery in the midst of a business continuity incident. The model has four chronological primary headlines, which steer the team through a quick-time crisis decision-making process. The procedure facilitates timely, systematic, rationalised and justified decisions, which can withstand post-event scrutiny. The disruption management model has been thoroughly tested within an emergency services environment and is proven to significantly support clear and concise decision making in a business continuity context.

  3. Emerging and Disruptive Technologies.

    Science.gov (United States)

    Kricka, Larry J

    2016-08-01

    Several emerging or disruptive technologies can be identified that might, at some point in the future, displace established laboratory medicine technologies and practices. These include increased automation in the form of robots, 3-D printing, technology convergence (e.g., plug-in glucose meters for smart phones), new point-of-care technologies (e.g., contact lenses with sensors, digital and wireless enabled pregnancy tests) and testing locations (e.g., Retail Health Clinics, new at-home testing formats), new types of specimens (e.g., cell free DNA), big biology/data (e.g., million genome projects), and new regulations (e.g., for laboratory developed tests). In addition, there are many emerging technologies (e.g., planar arrays, mass spectrometry) that might find even broader application in the future and therefore also disrupt current practice. One interesting source of disruptive technology may prove to be the Qualcomm Tricorder XPrize, currently in its final stages.

  4. Sustainable Disruption Management

    DEFF Research Database (Denmark)

    Vaaben, Bo Valdemar

    The world we live in is globalized. Goods are seldom made in the place where they are used or consumed, and we do increasingly travel to other countries for either business or pleasure. In our everyday lives we rely on well-functioning global transportations systems to continue the standard...... in the same way, when operation is disrupted. Never the less, we may recall that the Suez Canal was closed due to riots in Egypt, that the fuel price was impacted by threats of closing of the Strait of Hormuz, and we do from time to time hear about acts of piracy outside the coast of Somalia. All...... papers combining disruption management and flight planning through an integrated optimization approach. An additional contribution of the thesis is to show how flexible flight speeds can be used to improve recovery from disruptions, while at the same time allowing an airline to trade off fuel costs...

  5. Racial disparities: disruptive genes in prostate carcinogenesis.

    Science.gov (United States)

    Singh, Savita; Plaga, Alexis; Shukla, Girish C

    2017-06-01

    Population specific studies in prostate cancer (PCa) reveal a unique heterogeneous etiology. Various factors, such as genetics, environment and dietary regimen seems to determine disease progression, therapeutic resistance and rate of mortality. Enormous disparity documented in disease incidences, aggressiveness and mortality in PCa among AAs (African Americans) and CAs (Caucasian Americans) is attributed to the variations in genetics, epigenetics and their association with metabolism. Scientific and clinical evidences have revealed the influence of variations in Androgen Receptor (AR), RNAse L, macrophage scavenger receptor 1 ( MRS1 ), androgen metabolism by cytochrome P450 3A4, differential regulation of microRNAs, epigenetic alterations and diet in racial disparity in PCa incidences and mortality. Concerted efforts are needed to identify race specific prognostic markers and treatment regimen for a better management of the disease.

  6. Statistical analysis of JET disruptions

    International Nuclear Information System (INIS)

    Tanga, A.; Johnson, M.F.

    1991-07-01

    In the operation of JET and of any tokamak many discharges are terminated by a major disruption. The disruptive termination of a discharge is usually an unwanted event which may cause damage to the structure of the vessel. In a reactor disruptions are potentially a very serious problem, hence the importance of studying them and devising methods to avoid disruptions. Statistical information has been collected about the disruptions which have occurred at JET over a long span of operations. The analysis is focused on the operational aspects of the disruptions rather than on the underlining physics. (Author)

  7. Emerging and Disruptive Technologies

    OpenAIRE

    Kricka, Larry J.

    2016-01-01

    Several emerging or disruptive technologies can be identified that might, at some point in the future, displace established laboratory medicine technologies and practices. These include increased automation in the form of robots, 3-D printing, technology convergence (e.g., plug-in glucose meters for smart phones), new point-of-care technologies (e.g., contact lenses with sensors, digital and wireless enabled pregnancy tests) and testing locations (e.g., Retail Health Clinics, new at-home test...

  8. Disrupting the Industry with Play

    DEFF Research Database (Denmark)

    Lund, Henrik Hautop

    2016-01-01

    or two ago. This is significantly disrupting the industry in several market sectors. This paper describes the components of the playware and embodied artificial intelligence research that has led to disruption in the industrial robotics sector, and which points to the next disruption of the health care...

  9. Wound Disruption Following Colorectal Operations.

    Science.gov (United States)

    Moghadamyeghaneh, Zhobin; Hanna, Mark H; Carmichael, Joseph C; Mills, Steven; Pigazzi, Alessio; Nguyen, Ninh T; Stamos, Michael J

    2015-12-01

    Postoperative wound disruption is associated with high morbidity and mortality. We sought to identify the risk factors and outcomes of wound disruption following colorectal resection. The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database was used to examine the clinical data of patients who underwent colorectal resection from 2005 to 2013. Multivariate regression analysis was performed to identify risk factors of wound disruption. We sampled a total of 164,297 patients who underwent colorectal resection. Of these, 2073 (1.3 %) had wound disruption. Patients with wound disruption had significantly higher mortality (5.1 vs. 1.9 %, AOR: 1.46, P = 0.01). The highest risk of wound disruption was seen in patients with wound infection (4.8 vs. 0.9 %, AOR: 4.11, P disruption such as chronic steroid use (AOR: 1.71, P disruption compared to open surgery (AOR: 0.61, P disruption occurs in 1.3 % of colorectal resections, and it correlates with mortality of patients. Wound infection is the strongest predictor of wound disruption. Chronic steroid use, obesity, severe COPD, prolonged operation, non-elective admission, and serum albumin level are strongly associated with wound disruption. Utilization of the laparoscopic approach may decrease the risk of wound disruption when possible.

  10. Disruptive Space Technology

    OpenAIRE

    Benson, Jim

    2004-01-01

    In 1997 "The Innovator’s Dilemma" by Clayton M. Christensen became a popular book in the small satellite and launch vehicle communities. But like the weather, every one talks about “Disruptive Technology” but few do anything about it. In the ‘70s and ‘80s, people were looking for “Paradigm Shifts,” and since the resurrection of Donald Rumsfeld, a recent watchword has been “Transformational Technology.” But today’s buzzword is now “Responsive Space Systems.”

  11. Disruption - Access cards service

    CERN Multimedia

    2014-01-01

    We would like to inform you that between 10 November and 15 December 2014, the access cards service in Building 55 will be disrupted, as the GS Department has decided to improve the facilities for users of this building. During the work, you will find the registration, biometric registration and dosimeter exchange services on the second floor of Building 55 and the vehicle sticker service on the ground floor along with the access cards service. We thank you for your understanding and apologise for any inconvenience caused.

  12. Disruptions in the TFTR tokamak

    International Nuclear Information System (INIS)

    Janos, A.; Fredrickson, E.D.; McGuire, K.; Batha, S.H.; Bell, M.G.; Bitter, M.; Budny, R.; Bush, C.E.; Efthimion, P.C.; Hawryluk, R.J.; Hill, K.W.; Hosea, J.; Jobes, F.C.; Johnson, D.W.; Levinton, F.; Mansfield, D.; Meade, D.; Medley, S.S.; Monticello, D.; Mueller, D.; Nagayama, Y.; Owens, D.K.; Park, H.; Park, W.; Post, D.E.; Schivell, J.; Strachan, J.D.; Taylor, G.; Ulrickson, M.; Goeler, S. von; Wilfrid, E.; Wong, K.L.; Yamada, M.; Young, K.M.; Zarnstorff, M.C.; Zweben, S.J.; Drake, J.F.; Kleva, R.G.; Fleischmann, H.H.

    1993-03-01

    For a successful reactor, it will be useful to predict the occurrence of disruptions and to understand disruption effects including how a plasma disrupts onto the wall and how reproducibly it does so. Studies of disruptions on TFTR at both high-β pol and high-density have shown that, in both types, a fast growing m/n=1/1 mode plays an important role. In highdensity disruptions, a newly observed fast m/n = 1/1 mode occurs early in the thermal decay phase. For the first time in TFTR q-profile measurements just prior to disruptions have been made. Experimental studies of heat deposition patterns on the first wall of TFTR due to disruptions have provided information on MHD phenomena prior to or during the disruption, how the energy is released to the wall, and the reproducibility of the heat loads from disruptions. This information is important in the design of future devices such as ITER. Several new processes of runaway electron generation are theoretically suggested and their application to TFTR and ITER is considered, together with a preliminary assessment of x-ray data from runaways generated during disruptions

  13. Cell disruption for microalgae biorefineries.

    Science.gov (United States)

    Günerken, E; D'Hondt, E; Eppink, M H M; Garcia-Gonzalez, L; Elst, K; Wijffels, R H

    2015-01-01

    Microalgae are a potential source for various valuable chemicals for commercial applications ranging from nutraceuticals to fuels. Objective in a biorefinery is to utilize biomass ingredients efficiently similarly to petroleum refineries in which oil is fractionated in fuels and a variety of products with higher value. Downstream processes in microalgae biorefineries consist of different steps whereof cell disruption is the most crucial part. To maintain the functionality of algae biochemicals during cell disruption while obtaining high disruption yields is an important challenge. Despite this need, studies on mild disruption of microalgae cells are limited. This review article focuses on the evaluation of conventional and emerging cell disruption technologies, and a comparison thereof with respect to their potential for the future microalgae biorefineries. The discussed techniques are bead milling, high pressure homogenization, high speed homogenization, ultrasonication, microwave treatment, pulsed electric field treatment, non-mechanical cell disruption and some emerging technologies. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Disruptions in DIII-D

    International Nuclear Information System (INIS)

    Reiman, A.; Taylor, P.; Kellman, A.; LaHaye, R.

    1996-01-01

    We report on the results of a statistical analysis of the DIII-D disruption data base, and on an examination of a selected subset of the shots to determine the likely causes of disruptions. The statistical analysis focuses on the dependence of the disruption rate on key dimensionless parameters. We find that the disruption frequency is high at modest values of the parameters, and that it can be relatively low at operational limits. For example, the disruption frequency in an ITER relevant regime (β N /l i ∼ 2, 3 G > 0.6, where n G is the Greenwald limit) is approximately 23%. For this range of q, the disruption frequency rises only modestly to about 35% at the β limit, consistent with previous observations of a soft β limit for this q regime. For the range 6 95 G G < .9) in all q regimes we have studied. The location of the minimum moves to higher density with increasing q

  15. Chromosomal contact permits transcription between coregulated genes

    CSIR Research Space (South Africa)

    Fanucchi, Stephanie

    2013-10-01

    Full Text Available . To ask whether chromosomal contacts are required for cotranscription in multigene complexes, we devised a strategy using TALENs to cleave and disrupt gene loops in a well-characterized multigene complex. Monitoring this disruption using RNA FISH...

  16. Overview of core disruptive accidents

    International Nuclear Information System (INIS)

    Marchaterre, J.F.

    1977-01-01

    An overview of the analysis of core-disruptive accidents is given. These analyses are for the purpose of understanding and predicting fast reactor behavior in severe low probability accident conditions, to establish the consequences of such conditions and to provide a basis for evaluating consequence limiting design features. The methods are used to analyze core-disruptive accidents from initiating event to complete core disruption, the effects of the accident on reactor structures and the resulting radiological consequences are described

  17. Disrupted Refugee Family Life

    DEFF Research Database (Denmark)

    Shapiro, Ditte Krogh

    2017-01-01

    Fleeing civil war involves managing life threatening events and multiple disruptions of everyday life. The theoretical potentials of analysing the recreation of everyday family life among Syrian refugees in Denmark is explored based on conceptualizations that emphasize the collective agency...... of family members in social historical contexts. Studying the multiple perspectives of family members shows how social support conceptualized as care practises is conflictual in the changing everyday family practices that are transformed by policy. The purpose of studying how families manage to flee civil...... war and struggle to recreate an everyday life in exile is to contribute with contextualization and expansion of mainstream understandings of family life, suffering, and resilience in refugee family trajectories in multiple contexts....

  18. Disruptive Technology: An Uncertain Future

    Science.gov (United States)

    2005-05-21

    Technology that overturns market -- Military - Technology that causes a fundamental change in force structure, basing, and capability balance * Disruptive Technologies may arise from systems or enabling technology.

  19. Major disruption process in tokamak

    International Nuclear Information System (INIS)

    Kurita, Gen-ichi; Azumi, Masafumi; Tuda, Takashi; Takizuka, Tomonori; Tsunematsu, Toshihide; Tokuda, Shinji; Itoh, Kimitaka; Takeda, Tatsuoki

    1981-11-01

    The major disruption in a cylindrical tokamak is investigated by using the multi-helicity code, and the destabilization of the 3/2 mode by the mode coupling with the 2/1 mode is confirmed. The evolution of the magnetic field topology caused by the major disruption is studied in detail. The effect of the internal disruption on the 2/1 magnetic island width is also studied. The 2/1 magnetic island is not enhanced by the flattening of the q-profile due to the internal disruption. (author)

  20. Substantial decrease in cell wall α-1,3-glucan caused by disruption of the kexB gene encoding a subtilisin-like processing protease in Aspergillus oryzae.

    Science.gov (United States)

    Mizutani, Osamu; Shiina, Matsuko; Yoshimi, Akira; Sano, Motoaki; Watanabe, Takeshi; Yamagata, Youhei; Nakajima, Tasuku; Gomi, Katsuya; Abe, Keietsu

    2016-09-01

    Disruption of the kexB encoding a subtilisin-like processing protease in Aspergillus oryzae (ΔkexB) leads to substantial morphological defects when the cells are grown on Czapek-Dox agar plates. We previously found that the disruption of kexB causes a constitutive activation of the cell wall integrity pathway. To understand how the disruption of the kexB affects cell wall organization and components, we analyzed the cell wall of ΔkexB grown on the plates. The results revealed that both total N-acetylglucosamine content, which constitutes chitin, and chitin synthase activities were increased. Whereas total glucose content, which constitutes β-1,3-glucan and α-1,3-glucan, was decreased; this decrease was attributed to a remarkable decrease in α-1,3-glucan. Additionally, the β-1,3-glucan in the alkali-insoluble fraction of the ΔkexB showed a high degree of polymerization. These results suggested that the loss of α-1,3-glucan in the ΔkexB was compensated by increases in the chitin content and the average degree of β-1,3-glucan polymerization.

  1. Circadian Rhythm Disruption Promotes Lung Tumorigenesis.

    Science.gov (United States)

    Papagiannakopoulos, Thales; Bauer, Matthew R; Davidson, Shawn M; Heimann, Megan; Subbaraj, Lakshmipriya; Bhutkar, Arjun; Bartlebaugh, Jordan; Vander Heiden, Matthew G; Jacks, Tyler

    2016-08-09

    Circadian rhythms are 24-hr oscillations that control a variety of biological processes in living systems, including two hallmarks of cancer, cell division and metabolism. Circadian rhythm disruption by shift work is associated with greater risk for cancer development and poor prognosis, suggesting a putative tumor-suppressive role for circadian rhythm homeostasis. Using a genetically engineered mouse model of lung adenocarcinoma, we have characterized the effects of circadian rhythm disruption on lung tumorigenesis. We demonstrate that both physiologic perturbation (jet lag) and genetic mutation of the central circadian clock components decreased survival and promoted lung tumor growth and progression. The core circadian genes Per2 and Bmal1 were shown to have cell-autonomous tumor-suppressive roles in transformation and lung tumor progression. Loss of the central clock components led to increased c-Myc expression, enhanced proliferation, and metabolic dysregulation. Our findings demonstrate that both systemic and somatic disruption of circadian rhythms contribute to cancer progression. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Disrupting Ethnography through Rhizoanalysis

    Directory of Open Access Journals (Sweden)

    Diana Masny

    2014-10-01

    Full Text Available This article interrogates principles of ethnography in education proposed by Mills and Morton: raw tellings, analytic pattern, vignette and empathy. This article adopts a position that is uncomfortable, unconventional and interesting. It involves a deterritorialization/ rupture of ethnography in education in order to reterritorialize a different concept: rhizoanalysis, a way to position theory and data that is multilayered, complex and messy. Rhizoanalysis, the main focus of this article is not a method. It is an approach to research conditioned by a reality in which Deleuze and Guattari disrupt representation, interpretation and subjectivity. In this article, Multiple Literacies Theory, a theoretical and practical framework, becomes a lens to examine a rhizomatic study of a Korean family recently arrived to Australia and attending English as a second language classes. Observations and interviews recorded the daily lives of the family. The vignettes were selected by reading data intensively and immanently through a process of palpation, an innovative approach to educational research. Rhizoanalysis proposes to abandon the given and invent different ways of thinking about and doing research and what might happen when reading data differently, intensively and immanently, through Multiple Literacies Theory. Rhizoanalysis, a game-changer in the way research can be conducted, affords a different lens to tackle issues in education through research.

  3. Thigmotaxis Mediates Trail Odour Disruption.

    Science.gov (United States)

    Stringer, Lloyd D; Corn, Joshua E; Sik Roh, Hyun; Jiménez-Pérez, Alfredo; Manning, Lee-Anne M; Harper, Aimee R; Suckling, David M

    2017-05-10

    Disruption of foraging using oversupply of ant trail pheromones is a novel pest management application under investigation. It presents an opportunity to investigate the interaction of sensory modalities by removal of one of the modes. Superficially similar to sex pheromone-based mating disruption in moths, ant trail pheromone disruption lacks an equivalent mechanistic understanding of how the ants respond to an oversupply of their trail pheromone. Since significant compromise of one sensory modality essential for trail following (chemotaxis) has been demonstrated, we hypothesised that other sensory modalities such as thigmotaxis could act to reduce the impact on olfactory disruption of foraging behaviour. To test this, we provided a physical stimulus of thread to aid trailing by Argentine ants otherwise under disruptive pheromone concentrations. Trail following success was higher using a physical cue. While trail integrity reduced under continuous over-supply of trail pheromone delivered directly on the thread, provision of a physical cue in the form of thread slightly improved trail following and mediated trail disruption from high concentrations upwind. Our results indicate that ants are able to use physical structures to reduce but not eliminate the effects of trail pheromone disruption.

  4. Sleep disruption in chronic rhinosinusitis.

    Science.gov (United States)

    Mahdavinia, Mahboobeh; Schleimer, Robert P; Keshavarzian, Ali

    2017-05-01

    Chronic rhinosinusitis (CRS) is a common disease of the upper airways and paranasal sinuses with a marked decline in quality of life (QOL). CRS patients suffer from sleep disruption at a significantly higher proportion (60 to 75%) than in the general population (8-18 %). Sleep disruption in CRS causes decreased QOL and is linked to poor functional outcomes such as impaired cognitive function and depression. Areas covered: A systematic PubMed/Medline search was done to assess the results of studies that have investigated sleep and sleep disturbances in CRS. Expert commentary: These studies reported sleep disruption in most CRS patients. The main risk factors for sleep disruption in CRS include allergic rhinitis, smoking, and high SNOT-22 total scores. The literature is inconsistent with regard to the prevalence of sleep-related disordered breathing (e.g. obstructive sleep apnea) in CRS patients. Although nasal obstruction is linked to sleep disruption, the extent of sleep disruption in CRS seems to expand beyond that expected from physical blockage of the upper airways alone. Despite the high prevalence of sleep disruption in CRS, and its detrimental effects on QOL, the literature contains a paucity of studies that have investigated the mechanisms underlying this major problem in CRS.

  5. When Disruptive Approaches Meet Disruptive Technologies: Learning at a Distance.

    Science.gov (United States)

    Gibson, Chere Campbell

    2000-01-01

    Reviews research on constructivism in learning and selection of learning strategies. Suggests linking constructivism with instructional technologies for continuing medical education in order to "disrupt" reactive, habitual ways of learning and encourage active engagement. (SK)

  6. Plasma disruption modeling and simulation

    International Nuclear Information System (INIS)

    Hassanein, A.

    1994-01-01

    Disruptions in tokamak reactors are considered a limiting factor to successful operation and reliable design. The behavior of plasma-facing components during a disruption is critical to the overall integrity of the reactor. Erosion of plasma facing-material (PFM) surfaces due to thermal energy dump during the disruption can severely limit the lifetime of these components and thus diminish the economic feasibility of the reactor. A comprehensive understanding of the interplay of various physical processes during a disruption is essential for determining component lifetime and potentially improving the performance of such components. There are three principal stages in modeling the behavior of PFM during a disruption. Initially, the incident plasma particles will deposit their energy directly on the PFM surface, heating it to a very high temperature where ablation occurs. Models for plasma-material interactions have been developed and used to predict material thermal evolution during the disruption. Within a few microseconds after the start of the disruption, enough material is vaporized to intercept most of the incoming plasma particles. Models for plasma-vapor interactions are necessary to predict vapor cloud expansion and hydrodynamics. Continuous heating of the vapor cloud above the material surface by the incident plasma particles will excite, ionize, and cause vapor atoms to emit thermal radiation. Accurate models for radiation transport in the vapor are essential for calculating the net radiated flux to the material surface which determines the final erosion thickness and consequently component lifetime. A comprehensive model that takes into account various stages of plasma-material interaction has been developed and used to predict erosion rates during reactor disruption, as well during induced disruption in laboratory experiments

  7. Symposium on disruptive instabilities at Garching

    International Nuclear Information System (INIS)

    Lackner, K.

    1979-01-01

    The phenomenon of disruptive instabilities was investigated with a special care at the IPP at Garching. After lectures and panel sessions it appears suitable, to subdivide the disruptive phenomena into four classes: 1. The internal disruption (the socalled saw-tooth oscillators). 2. the socalled reconnection disruptions. 3. The large disruptions. 4. The small disruptions. The four appearance forms of the phenomena are briefly explained. (GG) [de

  8. A Network Disruption Modeling Tool

    National Research Council Canada - National Science Library

    Leinart, James

    1998-01-01

    Given that network disruption has been identified as a military objective and C2-attack has been identified as the mechanism to accomplish this objective, a target set must be acquired and priorities...

  9. Norrie disease gene is distinct from the monoamine oxidase genes

    OpenAIRE

    Sims, Katherine B.; Ozelius, Laurie; Corey, Timothy; Rinehart, William B.; Liberfarb, Ruth; Haines, Jonathan; Chen, Wei Jane; Norio, Reijo; Sankila, Eeva; de la Chapelle, Albert; Murphy, Dennis L.; Gusella, James; Breakefield, Xandra O.

    1989-01-01

    The genes for MAO-A and MAO-B appear to be very close to the Norrie disease gene, on the basis of loss and /or disruption of the MAO genes and activities in atypical Norrie disease patients deleted for the DXS7 locus; linkage among the MAO genes, the Norrie disease gene, and the DXS7 locus; and mapping of all these loci to the chromosomal region Xp11. The present study provides evidence that the MAO genes are not disrupted in “classic” Norrie disease patients. Genomic DNA from these “nondelet...

  10. DISRUPTIVE TECHNOLOGIES: AN EXPANDED VIEW

    OpenAIRE

    JAMES M. UTTERBACK; HAPPY J. ACEE

    2005-01-01

    The term "disruptive technology" as coined by Christensen (1997, The Innovator's Dilemma; How New Technologies Cause Great Firms to Fail. Harvard Business School Press) refers to a new technology having lower cost and performance measured by traditional criteria, but having higher ancillary performance. Christensen finds that disruptive technologies may enter and expand emerging market niches, improving with time and ultimately attacking established products in their traditional markets. This...

  11. Improvements in disruption prediction at ASDEX Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Aledda, R., E-mail: raffaele.aledda@diee.unica.it; Cannas, B., E-mail: cannas@diee.unica.it; Fanni, A., E-mail: fanni@diee.unica.it; Pau, A., E-mail: alessandro.pau@diee.unica.it; Sias, G., E-mail: giuliana.sias@diee.unica.it

    2015-10-15

    Highlights: • A disruption prediction system for AUG, based on a logistic model, is designed. • The length of the disruptive phase is set for each disruption in the training set. • The model is tested on dataset different from that used during the training phase. • The generalization capability and the aging of the model have been tested. • The predictor performance is compared with the locked mode detector. - Abstract: In large-scale tokamaks disruptions have the potential to create serious damage to the facility. Hence disruptions must be avoided, but, when a disruption is unavoidable, minimizing its severity is mandatory. A reliable detection of a disruptive event is required to trigger proper mitigation actions. To this purpose machine learning methods have been widely studied to design disruption prediction systems at ASDEX Upgrade. The training phase of the proposed approaches is based on the availability of disrupted and non-disrupted discharges. In literature disruptive configurations were assumed appearing into the last 45 ms of each disruption. Even if the achieved results in terms of correct predictions were good, it has to be highlighted that the choice of such a fixed temporal window might have limited the prediction performance. In fact, it generates confusing information in cases of disruptions with disruptive phase different from 45 ms. The assessment of a specific disruptive phase for each disruptive discharge represents a relevant issue in understanding the disruptive events. In this paper, the Mahalanobis distance is applied to define a specific disruptive phase for each disruption, and a logistic regressor has been trained as disruption predictor. The results show that enhancements on the achieved performance on disruption prediction are possible by defining a specific disruptive phase for each disruption.

  12. Improvements in disruption prediction at ASDEX Upgrade

    International Nuclear Information System (INIS)

    Aledda, R.; Cannas, B.; Fanni, A.; Pau, A.; Sias, G.

    2015-01-01

    Highlights: • A disruption prediction system for AUG, based on a logistic model, is designed. • The length of the disruptive phase is set for each disruption in the training set. • The model is tested on dataset different from that used during the training phase. • The generalization capability and the aging of the model have been tested. • The predictor performance is compared with the locked mode detector. - Abstract: In large-scale tokamaks disruptions have the potential to create serious damage to the facility. Hence disruptions must be avoided, but, when a disruption is unavoidable, minimizing its severity is mandatory. A reliable detection of a disruptive event is required to trigger proper mitigation actions. To this purpose machine learning methods have been widely studied to design disruption prediction systems at ASDEX Upgrade. The training phase of the proposed approaches is based on the availability of disrupted and non-disrupted discharges. In literature disruptive configurations were assumed appearing into the last 45 ms of each disruption. Even if the achieved results in terms of correct predictions were good, it has to be highlighted that the choice of such a fixed temporal window might have limited the prediction performance. In fact, it generates confusing information in cases of disruptions with disruptive phase different from 45 ms. The assessment of a specific disruptive phase for each disruptive discharge represents a relevant issue in understanding the disruptive events. In this paper, the Mahalanobis distance is applied to define a specific disruptive phase for each disruption, and a logistic regressor has been trained as disruption predictor. The results show that enhancements on the achieved performance on disruption prediction are possible by defining a specific disruptive phase for each disruption.

  13. Disruption and analysis of the clpB, clpC, and clpE genes in Lactococcus lactis: ClpE, a new Clp family in gram-positive bacteria

    DEFF Research Database (Denmark)

    Ingmer, Hanne; Vogensen, Finn K.; Hammer, Karin

    1999-01-01

    In the genome of the gram-positive bacterium Lactococcus lactis MG1363, we have identified three genes (clpC, clpE, and clpB) which encode Clp proteins containing two conserved ATP binding domains. The proteins encoded by two of the genes belong to the previously described ClpB and ClpC families....... The clpE gene, however, encodes a member of a new Clp protein family that is characterized by a short N-terminal domain including a putative zinc binding domain (-CX2CX22CX2C-). Expression of the 83-kDa ClpE protein as well as of the two proteins encoded by clpB was strongly induced by heat shock and...... was shown to participate in the degradation of randomly folded proteins in L. lactis, could be necessary for degrading proteins generated by certain types of stress....

  14. Characterization of a Bombyx mori nucleopolyhedrovirus with Bmvp80 disruption.

    Science.gov (United States)

    Tang, Xu-Dong; Xu, Yi-Peng; Yu, Lin-Lin; Lang, Guo-Jun; Tian, Cai-Hong; Zhao, Jin-Fang; Zhang, Chuan-Xi

    2008-12-01

    A BmNPV Bacmid with the Bmvp80 gene disrupted was constructed using the ET-recombination system in Escherichia coli to investigate the role of Bmvp80 during the baculovirus life cycle. Disruption of Bmvp80 resulted in single cell infection phenotype, whereas a rescue BmBacmid restored budded virus titers to wild type levels; however, the homologous gene Ac104 (Acvp80) from AcMNPV could not complement the BmBacmid lacking a functional Bmvp80 gene. Electron microscopy of cells transfected with BmNPV lacking functional Bmvp80 revealed that the number of nucleocapsids was markedly lower. These results suggest that Bmvp80 is essential for normal budded virus production and nucleocapsid maturation, and is functionally divergent between baculovirus species.

  15. Characterization of a dehydrogenase activity responsible for oxidation of 11-cis-retinol in the retinal pigment epithelium of mice with a disrupted RDH5 gene. A model for the human hereditary disease fundus albipunctatus.

    NARCIS (Netherlands)

    Jang, G.F.; Hooser, J.P. van; Kuksa, V.; McBee, J.K.; He, Y.G.; Janssen, J.J.M.; Driessen, C.A.G.G.; Palczewski, K.

    2001-01-01

    In the vertebrate retina, the final step of visual chromophore production is the oxidation of 11-cis-retinol to 11-cis-retinal. This reaction is catalyzed by 11-cis-retinol dehydrogenases (11-cis-RDHs), prior to the chromophore rejoining with the visual pigment apo-proteins. The RDH5 gene encodes a

  16. Disruptive event analysis: volcanism and igneous intrusion

    International Nuclear Information System (INIS)

    Crowe, B.M.

    1979-01-01

    Three basic topics are addressed for the disruptive event analysis: first, the range of disruptive consequences of a radioactive waste repository by volcanic activity; second, the possible reduction of the risk of disruption by volcanic activity through selective siting of a repository; and third, the quantification of the probability of repository disruption by volcanic activity

  17. Disruption studies on ASDEX upgrade

    International Nuclear Information System (INIS)

    Pautasso, G.; Egorov, S.; Finken, K.H.

    2003-01-01

    Disruptions generate large thermal and mechanical stresses on the tokamak components and are occasionally responsible for damages to the machine. For a future reactor disruptions have a significant impact on the design since all loading conditions must be analyzed in accordance with stricter design criteria (due to safety or difficult maintenance). Therefore the uncertainties affecting the predicted stresses must be reduced as much as possible with a more comprehensive set of measurements and analyses in this generation of experimental machines, and avoidance/predictive methods must be developed further. Disruption studies on ASDEX Upgrade are focused on these subjects, namely on: (1) understanding the physical mechanisms leading to this phenomenon in order to learn to avoid it or to predict its occurrence and to mitigate its effects; (2) analyzing the effects of disruptions on the machine to determine the functional dependence of the thermal and mechanical loads upon the discharge parameters. This allows, firstly, to dimension or reinforce the machine components to withstand these loads and, secondly, to extrapolate them to tokamaks still in the design phase; (3) learning to mitigate the consequence of disruptions, i.e. thermal loads, mechanical forces and runaways with injection of impurity pellets or gas. This paper is focused on most recent results concerning points, i.e. on the analysis of the degree of asymmetry of the forces and on the use of impurity puff for mitigation

  18. Disruption studies in ASDEX Upgrade

    International Nuclear Information System (INIS)

    Pautasso, G.

    2002-01-01

    Disruption generate large thermal and mechanical stresses on the tokamak components. For a future reactor disruptions have a significant impact on the design since all loading conditions must be analyzed in accordance with stricter design criteria (due to safety or difficult maintenance). Therefore the uncertainties affecting the predicted stresses must be reduced as much as possible with a more comprehensive set of measurements and analyses in this generation of experimental machines, and avoidance/ predictive methods must be developed further. The study of disruptions on ASDEX Upgrade is focused on these subjects, namely on: (1) understanding the physical mechanisms leading to this phenomenon and learning to avoid it or to predict its occurrence (with neural networks, for example) and to mitigate its effects; (2) analyzing the effects of disruptions on the machine to determine the functional dependence of the thermal and mechanical loads upon the discharge parameters. This allows to dimension or reinforce the machine components to withstand these loads and to extrapolate them to tokamaks still in the design phase; (3) learning to mitigate the consequence of disruptions. (author)

  19. Engineered chloroplast dsRNA silences cytochrome p450 monooxygenase, V-ATPase and chitin synthase genes in the insect gut and disrupts Helicoverpa zea larval development and pupation.

    Science.gov (United States)

    Jin, Shuangxia; Singh, Nameirakpam D; Li, Lebin; Zhang, Xianlong; Daniell, Henry

    2015-04-01

    In the past two decades, chloroplast genetic engineering has been advanced to achieve high-level protein accumulation but not for down-regulation of targeted genes. Therefore, in this report, lepidopteran chitin synthase (Chi), cytochrome P450 monooxygenase (P450) and V-ATPase dsRNAs were expressed via the chloroplast genome to study RNA interference (RNAi) of target genes in intended hosts. PCR and Southern blot analysis confirmed homoplasmy and site-specific integration of transgene cassettes into the chloroplast genomes. Northern blots and real-time qRT-PCR confirmed abundant processed and unprocessed dsRNA transcripts (up to 3.45 million copies of P450 dsRNAs/μg total RNA); the abundance of cleaved dsRNA was greater than the endogenous psbA transcript. Feeding of leaves expressing P450, Chi and V-ATPase dsRNA decreased transcription of the targeted gene to almost undetectable levels in the insect midgut, likely after further processing of dsRNA in their gut. Consequently, the net weight of larvae, growth and pupation rates were significantly reduced by chloroplast-derived dsRNAs. Taken together, successful expression of dsRNAs via the chloroplast genome for the first time opens the door to study RNA interference/processing within plastids. Most importantly, dsRNA expressed in chloroplasts can be utilized for gene inactivation to confer desired agronomic traits or for various biomedical applications, including down-regulation of dysfunctional genes in cancer or autoimmune disorders, after oral delivery of dsRNA bioencapsulated within plant cells. © 2015 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  20. Disruptive Technologies in Higher Education

    Science.gov (United States)

    Flavin, Michael

    2012-01-01

    This paper analyses the role of "disruptive" innovative technologies in higher education. In this country and elsewhere, Higher Education Institutions (HEIs) have invested significant sums in learning technologies, with Virtual Learning Environments (VLEs) being more or less universal, but these technologies have not been universally…

  1. Disruption mitigation on Tore Supra

    International Nuclear Information System (INIS)

    Martin, G.; Sourd, F.; Saint-Laurent, F.; Bucalossi, J.; Eriksson, L.G.

    2005-01-01

    During disruptions, the plasma energy is lost on the first wall within 1 ms, forces up to hundred tons are applied to the structures and kA of electrons are accelerated up to 50 MeV (runaway electrons). Already sources of concern in present day tokamaks, extrapolation to ITER shows the necessity of mitigation procedures, to avoid serious damages to in-vessel components. Massive gas injection was proposed, and encouraging tests have been done on Textor and DIII-D. Similar experiments where performed on Tore Supra, with the goal to validate their effect on runaway electrons, observed during the majority of disruptions. 0.1 mole of helium was injected within 5 ms in ohmic plasmas, up to 1.2 MA, either stable, or in a pre-disruptive phase (argon puffing). Beneficial effects where obtained: reduction of the current fall rate and eddy currents, total disappearance of runaway electrons and easy recovery for the next pulse, without noticeable helium pollution of following plasmas. Analysis of the 4 ms period between injection and disruption indicates that to reach these goals, one need to inject enough helium to keep it only partially ionised. It correspond to 0.1 g for Tore Supra, and extrapolate to hundred's of grams for ITER. (author)

  2. Disruptive Pupils and Teacher Stress.

    Science.gov (United States)

    Dunham, Jack

    1981-01-01

    Teachers have identified a number of stress situations in their work with disruptive children: insecurity due to student unpredictability, doubting their effectiveness, frustrated attempts at communication with other professionals, and feelings of isolation and limited social relationships (expressed by residential workers). (CT)

  3. JET and COMPASS asymmetrical disruptions

    Czech Academy of Sciences Publication Activity Database

    Gerasimov, S.N.; Abreu, P.; Baruzzo, M.; Drozdov, V.; Dvornova, A.; Havlíček, Josef; Hender, T.C.; Hronová-Bilyková, Olena; Kruezi, U.; Li, X.; Markovič, Tomáš; Pánek, Radomír; Rubinacci, G.; Tsalas, M.; Ventre, S.; Villone, F.; Zakharov, L.E.

    2015-01-01

    Roč. 55, č. 11 (2015), s. 113006-113006 ISSN 0029-5515 R&D Projects: GA MŠk(CZ) LM2011021 Institutional support: RVO:61389021 Keywords : tokamak * asymmetrical disruption * JET * COMPASS Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 4.040, year: 2015

  4. Disruption mitigation on Tore Supra

    International Nuclear Information System (INIS)

    Martin, G.; Sourd, F.; Saint-Laurent, F.; Bucalossi, J.; Eriksson, L.G.

    2004-01-01

    During disruptions, the plasma energy is lost on the first wall within 1 ms, forces up to hundred tons are applied to the structures and kA of electrons are accelerated up to 50 MeV (runaway electrons). Already sources of concern in present day tokamaks, extrapolation to ITER shows the necessity of mitigation procedures, to avoid serious damages to in-vessel components. Massive gas injection was proposed, and encouraging tests have been done on Textor and DIII-D. Similar experiments where performed on Tore Supra, with the goal to validate their effect on runaway electrons, observed during the majority of disruptions. 0.1 mole of helium was injected within 5 ms in ohmic plasmas, up to 1.2 MA, either stable, or in a pre-disruptive phase (argon puffing). Beneficial effects where obtained: reduction of the current fall rate and eddy currents, total disappearance of runaway electrons and easy recovery for the next pulse, without noticeable helium pollution of following plasmas. Analysis of the 4 ms period between injection and disruption indicates that to reach these goals, one need to inject enough helium to keep it only partially ionised. It corresponds to 0.1 g for Tore Supra, and extrapolate to hundreds of grams for ITER. (authors)

  5. Marital Alternatives and Marital Disruption.

    Science.gov (United States)

    Udry, J. Richard

    1981-01-01

    Explores the usefulness of "marital alternatives" as a dimension in explaining marital stability, using longitudinal data from a panel of married, White, urban couples from 16 urban areas. Results indicated the dimension of marital alternatives appeared to be a better predictor of marital disruption than marital satisfaction. (Author/RC)

  6. Will blockchain disrupt your business?

    OpenAIRE

    Schmeiss, Jessica

    2018-01-01

    Blockchain has been praised to be “the technology most likely to change the next decade of business”. The disruptive power of the blockchain technology is yet limited, says HIIG-researcher Jessica Schmeiss. Beyond the hype, there a opportunities for companies to make their current business models more cost-effective and more efficient.

  7. Supply disruption cost for power network planning

    International Nuclear Information System (INIS)

    Kjoelle, G.H.

    1992-09-01

    A description is given of the method of approach to calculate the total annual socio-economic cost of power supply disruption and non-supplied energy, included the utilities' cost for planning. The total socio-economic supply disruption cost is the sum of the customers' disruption cost and the utilities' cost for failure and disruption. The mean weighted disruption cost for Norway for one hour disruption is NOK 19 per kWh. The customers' annual disruption cost is calculated with basis in the specific disruption cost referred to heavy load (January) and dimensioning maximum loads. The loads are reduced by factors taking into account the time variations of the failure frequency, duration, the loads and the disruption cost. 6 refs

  8. In vivo immunotoxicity of perfluorooctane sulfonate in BALB/c mice: Identification of T-cell receptor and calcium-mediated signaling pathway disruption through gene expression profiling of the spleen.

    Science.gov (United States)

    Lv, Qi-Yan; Wan, Bin; Guo, Liang-Hong; Yang, Yu; Ren, Xiao-Min; Zhang, Hui

    2015-10-05

    Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant that is used worldwide and is continuously being detected in biota and the environment, thus presenting potential threats to the ecosystem and human health. Although PFOS is highly immunotoxic, its underlying molecular mechanisms remain largely unknown. The present study examined PFOS-induced immunotoxicity in the mouse spleen and explored its underlying mechanisms by gene expression profiling. Oral exposure of male BALB/c mice for three weeks followed by one-week recovery showed that a 10 mg/kg/day PFOS exposure damaged the splenic architecture, inhibited T-cell proliferation in response to mitogen, and increased the percentages of T helper (CD3(+)CD4(+)) and cytotoxic T (CD3(+)CD8(+)) cells, despite the decrease in the absolute number of these cells. A delayed type of PFOS immunotoxicity was observed, which mainly occurred during the recovery period. Global gene expression profiling of mouse spleens and QRT-PCR analyses suggest that PFOS inhibited the expression of genes involved in cell cycle regulation and NRF2-mediated oxidative stress response, and upregulated those in TCR signaling, calcium signaling, and p38/MAPK signaling pathways. Western blot analysis confirmed that the expressions of CAMK4, THEMIS, and CD3G, which were involved in the upregulated pathways, were induced upon PFOS exposure. Acute PFOS exposure modulated calcium homoeostasis in splenocytes. These results indicate that PFOS exposure can activate TCR signaling and calcium ion influx, which provides a clue for the potential mechanism of PFOS immunotoxicity. The altered signaling pathways by PFOS treatment as revealed in the present study might facilitate in better understanding PFOS immunotoxicity and explain the association between immune disease and PFOS exposure. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. Survey of disruption causes at JET

    International Nuclear Information System (INIS)

    De Vries, P.C.; Johnson, M.F.; Alper, B.; Hender, T.C.; Riccardo, V.; Buratti, P.; Koslowski, H.R.

    2011-01-01

    A survey has been carried out into the causes of all 2309 disruptions over the last decade of JET operations. The aim of this survey was to obtain a complete picture of all possible disruption causes, in order to devise better strategies to prevent or mitigate their impact. The analysis allows the effort to avoid or prevent JET disruptions to be more efficient and effective. As expected, a highly complex pattern of chain of events that led to disruptions emerged. It was found that the majority of disruptions had a technical root cause, for example due to control errors, or operator mistakes. These bring a random, non-physics, factor into the occurrence of disruptions and the disruption rate or disruptivity of a scenario may depend more on technical performance than on physics stability issues. The main root cause of JET disruptions was nevertheless due to neo-classical tearing modes that locked, closely followed in second place by disruptions due to human error. The development of more robust operational scenarios has reduced the JET disruption rate over the last decade from about 15% to below 4%. A fraction of all disruptions was caused by very fast, precursorless unpredictable events. The occurrence of these disruptions may set a lower limit of 0.4% to the disruption rate of JET. If one considers on top of that human error and all unforeseen failures of heating or control systems this lower limit may rise to 1.0% or 1.6%, respectively.

  10. Structured Literature Review of digital disruption literature

    DEFF Research Database (Denmark)

    Vesti, Helle; Rosenstand, Claus Andreas Foss; Gertsen, Frank

    2018-01-01

    Digital disruption is a term/phenomenon frequently appearing in innovation management literature. However, no academic consensus exists as to what it entails; conceptual nor theoretical. We use the SLR-method (Structured Literature Review) to investigate digital disruption literature. A SLR......-study conducted in 2017 revealed some useful information on how disruption and digital disruption literature has developed over a specific period. However, this study was less representative of papers addressing digital disruption; which is the in-depth subject of this paper. To accommodate this, we intend...... to conduct a similar SLR-study assembling a body literature having digital disruption as the only common denominator...

  11. Targeted disruption of exons 1 to 6 of the Fanconi Anemia group A gene leads to growth retardation, strain-specific microphthalmia, meiotic defects and primordial germ cell hypoplasia.

    Science.gov (United States)

    Wong, Jasmine C Y; Alon, Noa; Mckerlie, Colin; Huang, Jun R; Meyn, M Stephen; Buchwald, Manuel

    2003-08-15

    Fanconi Anemia (FA) is an autosomal recessive disorder characterized by cellular hypersensitivity to DNA cross-linking agents. Recent studies suggest that FA proteins share a common pathway with BRCA proteins. To study the in vivo role of the FA group A gene (Fanca), gene-targeting techniques were used to generate Fanca(tm1Hsc) mice in which Fanca exons 1-6 were replaced by a beta-galactosidase reporter construct. Fanca(tm1.1Hsc) mice were generated by Cre-mediated removal of the neomycin cassette in Fanca(tm1Hsc) mice. Fanca(tm1.1Hsc) homozygotes display FA-like phenotypes including growth retardation, microphthalmia and craniofacial malformations that are not found in other Fanca mouse models, and the genetic background affects manifestation of certain phenotypes. Both male and female mice homozygous for Fanca mutation exhibit hypogonadism, and homozygous females demonstrate premature reproductive senescence and an increased incidence of ovarian cysts. We showed that fertility defects in Fanca(tm1.1Hsc) homozygotes might be related to a diminished population of primordial germ cells (PGCs) during migration into the gonadal ridges. We also found a high level of Fanca expression in pachytene spermatocytes. Fanca(tm1Hsc) homozygous males exhibited an elevated frequency of mispaired meiotic chromosomes and increased apoptosis in germ cells, implicating a role for Fanca in meiotic recombination. However, the localization of Rad51, Brca1, Fancd2 and Mlh1 appeared normal on Fanca(tm1Hsc) homozygous meiotic chromosomes. Taken together, our results suggest that the FA pathway plays a role in the maintenance of reproductive germ cells and in meiotic recombination.

  12. Disruptive technologies and transportation : final report.

    Science.gov (United States)

    2016-06-01

    Disruptive technologies refer to innovations that, at first, may be considered unproven, lacking refinement, relatively unknown, or even impractical, but ultimately they supplant existing technologies and/or applications. In general, disruptive techn...

  13. Disrupting reconsolidation: pharmacological and behavioral manipulations

    NARCIS (Netherlands)

    Soeter, M.; Kindt, M.

    2011-01-01

    We previously demonstrated that disrupting reconsolidation by pharmacological manipulations "deleted" the emotional expression of a fear memory in humans. If we are to target reconsolidation in patients with anxiety disorders, the disruption of reconsolidation should produce content-limited

  14. Disrupting the habit of interviewing

    Directory of Open Access Journals (Sweden)

    Eileen Honan

    2014-06-01

    Full Text Available This paper contributes to the growing domain of ‘post-qualitative’ research and experiments with a new (representational form to move away from traditional and clichéd descriptions of research methods. In this paper, I want to interrogate the category of interview, and the habit of interviewing, to disrupt the clichés, so as to allow thinking of different ways of writing/speaking/representing the interactions between researcher and researched that will breathe new life into qualitative inquiries. I will attempt to flatten and shred, destabilise and disrupt our common-sense ideas about interview, including those held most sacred to the qualitative community, that of anonymity and confidentiality, as well as the privilege of the ‘transcript’ in re-presenting interview data.

  15. Bodily illusions disrupt tactile sensations.

    Science.gov (United States)

    D'Amour, Sarah; Pritchett, Lisa M; Harris, Laurence R

    2015-02-01

    To accurately interpret tactile information, the brain needs to have an accurate representation of the body to which to refer the sensations. Despite this, body representation has only recently been incorporated into the study of tactile perception. Here, we investigate whether distortions of body representation affect tactile sensations. We perceptually altered the length of the arm and the width of the waist using a tendon vibration illusion and measured spatial acuity and sensitivity. Surprisingly, we found reduction in both tactile acuity and sensitivity thresholds when the arm or waist was perceptually altered, which indicates a general disruption of low-level tactile processing. We postulate that the disruptive changes correspond to the preliminary stage as the body representation starts to change and may give new insights into sensory processing in people with long-term or sudden abnormal body representation such as are found in eating disorders or following amputation.

  16. Disruptive technologies - widening the scope -

    OpenAIRE

    Ruhlig, Klaus; Wiemken, Uwe

    2006-01-01

    The term „disruptive technologies” was introduced 1997 by Clayton Christensen in the context of innovations in the business world based upon technological developments. It was meant to sharpen the view for new technologies which can „disrupt” the economic context of a business. Since then it inspired other communities like so many terms in English (or American) language. One of these is the domain of international Research & Technology (R&T) cooperation and technological forecasting for publi...

  17. Disruptive technologies in higher education

    Directory of Open Access Journals (Sweden)

    Michael Flavin

    2012-08-01

    Full Text Available This paper analyses the role of “disruptive” innovative technologies in higher education. In this country and elsewhere, Higher Education Institutions (HEIs have invested significant sums in learning technologies, with Virtual Learning Environments (VLEs being more or less universal, but these technologies have not been universally adopted and used by students and staff. Instead, other technologies not owned or controlled by HEIs are widely used to support learning and teaching. According to Christensen's theory of Disruptive Innovation, these disruptive technologies are not designed explicitly to support learning and teaching in higher education, but have educational potential. This study uses Activity Theory and Expansive Learning to analyse data regarding the impact of disruptive technologies. The data were obtained through a questionnaire survey about awareness and use of technologies, and through observation and interviews, exploring participants’ actual practice. The survey answers tended to endorse Disruptive Innovation theory, with participants establishing meanings for technologies through their use of them, rather than in keeping with a designer's intentions. Observation revealed that learners use a narrow range of technologies to support learning, but with a tendency to use resources other than those supplied by their HEIs. Interviews showed that participants use simple and convenient technologies to support their learning and teaching. This study identifies a contradiction between learning technologies made available by HEIs, and technologies used in practice. There is no evidence to suggest that a wide range of technologies is being used to support learning and teaching. Instead, a small range of technologies is being used for a wide range of tasks. Students and lecturers are not dependent on their HEIs to support learning and teaching. Instead, they self-select technologies, with use weighted towards established brands. The

  18. Thyroid effects of endocrine disrupting chemicals

    DEFF Research Database (Denmark)

    Boas, Malene; Feldt-Rasmussen, Ulla; Main, Katharina M

    2012-01-01

    In recent years, many studies of thyroid-disrupting effects of environmental chemicals have been published. Of special concern is the exposure of pregnant women and infants, as thyroid disruption of the developing organism may have deleterious effects on neurological outcome. Chemicals may exert ...... thyroid-disrupting effects, and there is emerging evidence that also phthalates, bisphenol A, brominated flame retardants and perfluorinated chemicals may have thyroid disrupting properties....

  19. Sideways Force Produced During Disruptions

    Science.gov (United States)

    Strauss, H. R.; Paccagnella, R.; Breslau, J.; Jardin, S.; Sugiyama, L.

    2012-10-01

    We extend previous studies [1] of vertical displacement events (VDE) which can produce disruptions. The emphasis is on the non axisymmetric ``sideways'' wall force Fx. Simulations are performed using the M3D [2] code. A VDE expels magnetic flux through the resistive wall until the last closed flux surface has q VDE is presented. The wall force depends strongly on γτw, where γ is the mode growth rate and τw is the wall resistive penetration time. The force Fx is largest when γτw is a constant of order unity, which depends on the initial conditions. For large values of γτw, the wall force asymptotes to a relatively smaller value, well below the critical value ITER is designed to withstand. The principle of disruption mitigation by massive gas injection is to cause a disruption with large γτw. [4pt] [1] H. R. Strauss, R. Paccagnella, and J. Breslau,Phys. Plasmas 17, 082505 (2010) [2] W. Park, E.V. Belova, G.Y. Fu, X. Tang, H.R. Strauss, L.E. Sugiyama, Phys. Plasmas 6, 1796 (1999).

  20. Engineering analysis of TFTR disruption

    International Nuclear Information System (INIS)

    Murray, J.G.; Rothe, K.E.; Bronner, G.

    1984-09-01

    This report covers an engineering approach quantifying the currents, forces, and times, as well as plasma position, for the worst-case disruption based on engineerign circuit assumptions for the plasma. As the plasma moves toward the wall during the current-decay phase of disruption, the wall currents affect the rate of movement and, hence, the decay time. The calculated structure-induced currents differ considerably from those calculated using a presently available criterion, which specifies that the plasma remains stationary in the center of the torus while decaying in 10 ms. This report outlines the method and basis for the engineering calculation used to determine the current and forces as a function of the circuit characteristics. It provides specific calculations for the Tokamak Fusion Test Reactor (TFTR) with variations in parameters such as the thermal decay time, the torus resistance, and plasma temperature during the current decay. The study reviews possible ways to reduce the disruption damage of TFTR by reducing the magnitude of the plasma external field energy that is absorbed by the plasma during the current decay

  1. Engineering analysis of TFTR disruption

    Energy Technology Data Exchange (ETDEWEB)

    Murray, J.G.; Rothe, K.E.; Bronner, G.

    1984-09-01

    This report covers an engineering approach quantifying the currents, forces, and times, as well as plasma position, for the worst-case disruption based on engineerign circuit assumptions for the plasma. As the plasma moves toward the wall during the current-decay phase of disruption, the wall currents affect the rate of movement and, hence, the decay time. The calculated structure-induced currents differ considerably from those calculated using a presently available criterion, which specifies that the plasma remains stationary in the center of the torus while decaying in 10 ms. This report outlines the method and basis for the engineering calculation used to determine the current and forces as a function of the circuit characteristics. It provides specific calculations for the Tokamak Fusion Test Reactor (TFTR) with variations in parameters such as the thermal decay time, the torus resistance, and plasma temperature during the current decay. The study reviews possible ways to reduce the disruption damage of TFTR by reducing the magnitude of the plasma external field energy that is absorbed by the plasma during the current decay.

  2. Molecular targets in radiation-induced blood-brain barrier disruption

    International Nuclear Information System (INIS)

    Nordal, Robert A.; Wong, C. Shun

    2005-01-01

    Disruption of the blood-brain barrier (BBB) is a key feature of radiation injury to the central nervous system. Studies suggest that endothelial cell apoptosis, gene expression changes, and alteration of the microenvironment are important in initiation and progression of injury. Although substantial effort has been directed at understanding the impact of radiation on endothelial cells and oligodendrocytes, growing evidence suggests that other cell types, including astrocytes, are important in responses that include induced gene expression and microenvironmental changes. Endothelial apoptosis is important in early BBB disruption. Hypoxia and oxidative stress in the later period that precedes tissue damage might lead to astrocytic responses that impact cell survival and cell interactions. Cell death, gene expression changes, and a toxic microenvironment can be viewed as interacting elements in a model of radiation-induced disruption of the BBB. These processes implicate particular genes and proteins as targets in potential strategies for neuroprotection

  3. Probabilistic analysis of tokamak plasma disruptions

    International Nuclear Information System (INIS)

    Sanzo, D.L.; Apostolakis, G.E.

    1985-01-01

    An approximate analytical solution to the heat conduction equations used in modeling component melting and vaporization resulting from plasma disruptions is presented. This solution is then used to propagate uncertainties in the input data characterizing disruptions, namely, energy density and disruption time, to obtain a probabilistic description of the output variables of interest, material melted and vaporized. (orig.)

  4. Disruptive innovation as an entrepreneurial process

    NARCIS (Netherlands)

    Chandra, Y.; Yang, S.-J.S.; Singh, P.; Prajogo, D.; O'Neill, P.; Rahman, S.

    2008-01-01

    Research on conditions and causal mechanisms that influence disruptive innovation has been relatively unexplored in the extant research in disruptive innovation. By re-conceptualizing disruptive innovation as an entrepreneurial process at product, firm and industry levels, this paper draws on

  5. 3rd Annual Disruptive Technology Conference

    Science.gov (United States)

    2006-09-07

    Panel -- The Warfighter’s Perspective The Impact of Disruptive Technologies on Joint Warfighting MG Michael Vane, USA, Vice Director for Force...Structure, Resources & Assessment, Joint Staff, J-8 Panel -- Perspectives of Change: Identifying the Emerging Commercial Disruptive Technologies Decision...Mark Lucas, Board Member OSGeo, RadiantBlue Technologies Panel -- The Search for Disruptive Technologies - a “Blue Force” Multiplier Advanced

  6. Disruption and Distinctiveness in Higher Education

    Science.gov (United States)

    Purcell, Wendy

    2014-01-01

    "Disruption"--while an evocative word triggering feelings of anxiety and perhaps even fear--also signals renewal and growth. The Higher Education (HE) sector in England has experienced some profound disruption over the years, and yet has emerged stronger and renewed in many ways. The impact of recent disruptive forces, from fees to the…

  7. Statistical analysis of disruptions in JET

    International Nuclear Information System (INIS)

    De Vries, P.C.; Johnson, M.F.; Segui, I.

    2009-01-01

    The disruption rate (the percentage of discharges that disrupt) in JET was found to drop steadily over the years. Recent campaigns (2005-2007) show a yearly averaged disruption rate of only 6% while from 1991 to 1995 this was often higher than 20%. Besides the disruption rate, the so-called disruptivity, or the likelihood of a disruption depending on the plasma parameters, has been determined. The disruptivity of plasmas was found to be significantly higher close to the three main operational boundaries for tokamaks; the low-q, high density and β-limit. The frequency at which JET operated close to the density-limit increased six fold over the last decade; however, only a small reduction in disruptivity was found. Similarly the disruptivity close to the low-q and β-limit was found to be unchanged. The most significant reduction in disruptivity was found far from the operational boundaries, leading to the conclusion that the improved disruption rate is due to a better technical capability of operating JET, instead of safer operations close to the physics limits. The statistics showed that a simple protection system was able to mitigate the forces of a large fraction of disruptions, although it has proved to be at present more difficult to ameliorate the heat flux.

  8. Routine Responses to Disruption of Routines

    Science.gov (United States)

    Guha, Mahua

    2015-01-01

    "Organisational routines" is a widely studied research area. However, there is a dearth of research on disruption of routines. The few studies on disruption of routines discussed problem-solving activities that are carried out in response to disruption. In contrast, this study develops a theory of "solution routines" that are a…

  9. Impaired degradation of inhibitory subunit of NF-κB (IκB) and β-catenin as a result of targeted disruption of the β-TrCP1 gene

    Science.gov (United States)

    Nakayama, Keiko; Hatakeyama, Shigetsugu; Maruyama, Shun-ichiro; Kikuchi, Akira; Onoé, Kazunori; Good, Robert A.; Nakayama, Keiichi I.

    2003-01-01

    β-TrCP1 (also known as Fbw1a or FWD1) is the F-box protein component of an Skp1/Cul1/F-box (SCF)-type ubiquitin ligase complex. Although biochemical studies have suggested that β-TrCP1 targets inhibitory subunit of NF-κB(IκB) proteins and β-catenin for ubiquitylation, the physiological role of β-TrCP1 in mammals has remained unclear. We have now generated mice deficient in β-TrCP1 and shown that the degradation of IκBα and IκBβ is reproducibly, but not completely, impaired in the cells of these animals. The nuclear translocation and DNA-binding activity of NF-κB as well as the ability of this transcription factor to activate a luciferase reporter gene were also inhibited in β-TrCP1–/– cells compared with those apparent in wild-type cells. The subcellular localization of β-catenin was altered markedly in β-TrCP1–/– cells. Furthermore, the rate of proliferation was reduced and both cell size and the percentage of polyploid cells were increased in embryonic fibroblasts derived from β-TrCP1–/– mice pared with the corresponding wild-type cells. These results suggest that β-TrCP1 contributes to, but is not absolutely required for, the degradation of IκB and β-catenin and the consequent regulation of the NF-κB and Wnt signaling pathways, respectively. In addition, they implicate β-TrCP1 in the maintenance of ploidy during cell-cycle progression. PMID:12843402

  10. From Digital Disruption to Business Model Scalability

    DEFF Research Database (Denmark)

    Nielsen, Christian; Lund, Morten; Thomsen, Peter Poulsen

    2017-01-01

    This article discusses the terms disruption, digital disruption, business models and business model scalability. It illustrates how managers should be using these terms for the benefit of their business by developing business models capable of achieving exponentially increasing returns to scale...... will seldom lead to business model scalability capable of competing with digital disruption(s)....... as a response to digital disruption. A series of case studies illustrate that besides frequent existing messages in the business literature relating to the importance of creating agile businesses, both in growing and declining economies, as well as hard to copy value propositions or value propositions that take...

  11. Towards a Disruptive Digital Platform Model

    DEFF Research Database (Denmark)

    Kazan, Erol

    that digital platforms leverage on three strategic design elements (i.e., business, architecture, and technology design) to create supportive conditions for facilitating disruption. To shed light on disruptive digital platforms, I opted for payment platforms as my empirical context and unit of analysis......Digital platforms are layered modular information technology architectures that support disruption. Digital platforms are particularly disruptive, as they facilitate the quick release of digital innovations that may replace established innovations. Yet, despite their support for disruption, we have...... not fully understood how such digital platforms can be strategically designed and configured to facilitate disruption. To that end, this thesis endeavors to unravel disruptive digital platforms from the supply perspective that are grounded on strategic digital platform design elements. I suggest...

  12. Disruption of mouse Cenpj, a regulator of centriole biogenesis, phenocopies Seckel syndrome

    OpenAIRE

    McIntyre, Rebecca E; Lakshminarasimhan Chavali, Pavithra; Ismail, Ozama; Carragher, Damian M; Sanchez-Andrade, Gabriela; Forment, Josep V; Fu, Beiyuan; Del Castillo Velasco-Herrera, Martin; Edwards, Andrew; van der Weyden, Louise; Yang, Fengtang; Ramirez-Solis, Ramiro; Estabel, Jeanne; Gallagher, Ferdia A; Logan, Darren W

    2012-01-01

    Disruption of the centromere protein J gene, CENPJ (CPAP, MCPH6, SCKL4), which is a highly conserved and ubiquitiously expressed centrosomal protein, has been associated with primary microcephaly and the microcephalic primordial dwarfism disorder Seckel syndrome. The mechanism by which disruption of CENPJ causes the proportionate, primordial growth failure that is characteristic of Seckel syndrome is unknown. By generating a hypomorphic allele of Cenpj, we have developed a mouse (Cenpj(tm/tm)...

  13. Professional Disruption in Health Regulation

    DEFF Research Database (Denmark)

    Hasselbalch, Jacob

    2016-01-01

    How do professions respond to fast-moving technological changes? Disruptive innovations overturn expectations about how markets function and develop, and they often raise moral, legal and scientific concerns among professionals. Sudden technological changes can result in a state of professional...... recent revision to the Tobacco Products Directive. Medical and public health professionals that control tobacco issues were challenged by a coalition of e-cigarette industry representatives, e-cigarette users, and liberal politicians. The challengers drew on the contending norm of harm reduction...

  14. Disruptive Innovation in Numerical Hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Waltz, Jacob I. [Los Alamos National Laboratory

    2012-09-06

    We propose the research and development of a high-fidelity hydrodynamic algorithm for tetrahedral meshes that will lead to a disruptive innovation in the numerical modeling of Laboratory problems. Our proposed innovation has the potential to reduce turnaround time by orders of magnitude relative to Advanced Simulation and Computing (ASC) codes; reduce simulation setup costs by millions of dollars per year; and effectively leverage Graphics Processing Unit (GPU) and future Exascale computing hardware. If successful, this work will lead to a dramatic leap forward in the Laboratory's quest for a predictive simulation capability.

  15. Disruptive innovation for social change.

    Science.gov (United States)

    Christensen, Clayton M; Baumann, Heiner; Ruggles, Rudy; Sadtler, Thomas M

    2006-12-01

    Countries, organizations, and individuals around the globe spend aggressively to solve social problems, but these efforts often fail to deliver. Misdirected investment is the primary reason for that failure. Most of the money earmarked for social initiatives goes to organizations that are structured to support specific groups of recipients, often with sophisticated solutions. Such organizations rarely reach the broader populations that could be served by simpler alternatives. There is, however, an effective way to get to those underserved populations. The authors call it "catalytic innovation." Based on Clayton Christensen's disruptive-innovation model, catalytic innovations challenge organizational incumbents by offering simpler, good-enough solutions aimed at underserved groups. Unlike disruptive innovations, though, catalytic innovations are focused on creating social change. Catalytic innovators are defined by five distinct qualities. First, they create social change through scaling and replication. Second, they meet a need that is either overserved (that is, the existing solution is more complex than necessary for many people) or not served at all. Third, the products and services they offer are simpler and cheaper than alternatives, but recipients view them as good enough. Fourth, they bring in resources in ways that initially seem unattractive to incumbents. And fifth, they are often ignored, put down, or even encouraged by existing organizations, which don't see the catalytic innovators' solutions as viable. As the authors show through examples in health care, education, and economic development, both nonprofit and for-profit groups are finding ways to create catalytic innovation that drives social change.

  16. Modeling SOL evolution during disruptions

    International Nuclear Information System (INIS)

    Rognlien, T.D.; Cohen, R.H.; Crotinger, J.A.

    1996-01-01

    We present the status of our models and transport simulations of the 2-D evolution of the scrape-off layer (SOL) during tokamak disruptions. This evolution is important for several reasons: It determines how the power from the core plasma is distributed on material surfaces, how impurities from those surfaces or from gas injection migrate back to the core region, and what are the properties of the SOL for carrying halo currents. We simulate this plasma in a time-dependent fashion using the SOL transport code UEDGE. This code models the SOL plasma using fluid equations of plasma density, parallel momentum (along the magnetic field), electron energy, ion energy, and neutral gas density. A multispecies model is used to follow the density of different charge-states of impurities. The parallel transport is classical but with kinetic modifications; these are presently treated by flux limits, but we have initiated more sophisticated models giving the correct long-mean-free path limit. The cross-field transport is anomalous, and one of the results of this work is to determine reasonable values to characterize disruptions. Our primary focus is on the initial thermal quench phase when most of the core energy is lost, but the total current is maintained. The impact of edge currents on the MHD equilibrium will be discussed

  17. Monitoring-induced disruption in skilled typewriting.

    Science.gov (United States)

    Snyder, Kristy M; Logan, Gordon D

    2013-10-01

    It is often disruptive to attend to the details of one's expert performance. The current work presents four experiments that utilized a monitor to report protocol to evaluate the sufficiency of three accounts of monitoring-induced disruption. The inhibition hypothesis states that disruption results from costs associated with preparing to withhold inappropriate responses. The dual-task hypothesis states that disruption results from maintaining monitored information in working memory. The implicit-explicit hypothesis states that disruption results from explicitly monitoring details of performance that are normally implicit. The findings suggest that all three hypotheses are sufficient to produce disruption, but inhibition and dual-task costs are not necessary. Experiment 1 showed that monitoring to report was disruptive even when there was no requirement to inhibit. Experiment 2 showed that maintaining information in working memory caused some disruption but much less than monitoring to report. Experiment 4 showed that monitoring to inhibit was more disruptive than monitoring to report, suggesting that monitoring is more disruptive when it is combined with other task requirements, such as inhibition. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  18. β limit disruptions in the TFTR tokamak

    International Nuclear Information System (INIS)

    Fredrickson, E.D.; McGuire, K.; Janos, A.; Bell, M.; Budny, R.V.; Bush, C.E.; Manickam, J.; Mynick, H.; Nazikian, R.; Taylor, G.

    1994-11-01

    A disruptive β limit (β = plasma pressure/magnetic pressure) is observed in high performance plasmas in TFTR. The MHD character of these disruptions differs substantially from the disruptions in high density plasmas (density limit disruptions) on TFTR. The high β disruptions can occur with less than a milliseconds warning in the form of a fast growing precursor. The precursor appears to be an external kink or internal (m,n)=(1,1) kink strongly coupled through finite β effects and toroidal terms to higher m components. It does not have the open-quote cold bubble close-quote structure found in density limit disruptions. There is also no evidence for a change in the internal inductance, i.e., a major reconnection of the flux, at the time of the thermal quench

  19. The Effects of Disruption on Strategic Management

    DEFF Research Database (Denmark)

    Drejer, Anders

    2017-01-01

    There is a lot of interest in Disruption these days even though the concept itself is still under formation. Disruption can be traced back to the idea of disruptive technological change and the late 1990s but has reemerged in the public eye in current years under guises such as Big Data......, Digitalization, Globalization and much more. Furthermore, the effects of disruption are now being felt by organizations and industries all over the world. In this paper, we will try to outline and illustrate some of those effects using the case-study of an international, Danish, SME. The case company has been...... forced to face some challenges caused by disruption and in the process of doing so has changed its strategy process significantly towards a more learning based approach to strategic management. Keywords: disruption; case- study; SME; strategy process....

  20. Multistage Logistic Network Optimization under Disruption Risk

    OpenAIRE

    Rusman, Muhammad

    2013-01-01

    Getting over disruptions risk has been a challenging issue for many companies under the globalization that will link to potential external source such as demand uncertainties, natural disasters, and terrorist attacks. The disruption is an unexpected event that disturbs normal flows of products and materials within a supply chain. The disruption at one members of supply chain will propagate the offers and finally affect significant impacts on the entire chain. If we look back...

  1. CATASTROPHIC DISRUPTION OF COMET ISON

    Energy Technology Data Exchange (ETDEWEB)

    Keane, Jacqueline V.; Kleyna, Jan T.; Riesen, Timm-Emmanuel; Meech, Karen J. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Milam, Stefanie N.; Charnley, Steven B. [Astrochemistry Laboratory, NASA GSFC, MS 690, Greenbelt, MD 20771 (United States); Coulson, Iain M. [Joint Astronomy Center, 660 North Aohoku Place, Hilo, HI 96720 (United States); Sekanina, Zdenek [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Kracht, Rainer, E-mail: keane@ifa.hawaii.edu [Ostlandring 53, D-25335 Elmshorn, Schleswig-Holstein (Germany)

    2016-11-10

    We report submillimeter 450 and 850 μ m dust continuum observations for comet C/2012 S1 (ISON) obtained at heliocentric distances 0.31–0.08 au prior to perihelion on 2013 November 28 ( r {sub h} = 0.0125 au). These observations reveal a rapidly varying dust environment in which the dust emission was initially point-like. As ISON approached perihelion, the continuum emission became an elongated dust column spread out over as much as 60″ (>10{sup 5} km) in the anti-solar direction. Deconvolution of the November 28.04 850 μ m image reveals numerous distinct clumps consistent with the catastrophic disruption of comet ISON, producing ∼5.2 × 10{sup 10} kg of submillimeter-sized dust. Orbital computations suggest that the SCUBA-2 emission peak coincides with the comet's residual nucleus.

  2. Current disruption in toroidal devices

    International Nuclear Information System (INIS)

    1979-07-01

    Attempts at raising the density or the plasma current in a tokamak above certain critical values generally result in termination of the discharge by a disruption. This sudden end of the plasma current and plasma confinement is accompanied by large induced voltages and currents in the outer structures which, in large tokamaks, can only be handled with considerable effort, and which will probably only be tolerable in reactors as rare accidents. Because of its crucial importance for the construction and operation of tokamaks, this phenomenon and its theoretical interpretation were the subject of a three-day symposium organized by the International Atomic Energy Agency and Max-Planck-Institut fuer Plasmaphysik at Garching from February 14 to 16. (orig./HT)

  3. Catastrophic Disruption of Comet ISON

    Science.gov (United States)

    Keane, Jacqueline V.; Milam, Stefanie N.; Coulson, Iain M.; Kleyna, Jan T.; Sekanina, Zdenek; Kracht, Rainer; Riesen, Timm-Emmanuel; Meech, Karen J.; Charnley, Steven B.

    2016-01-01

    We report submillimeter 450 and 850 microns dust continuum observations for comet C/2012 S1 (ISON) obtained at heliocentric distances 0.31-0.08 au prior to perihelion on 2013 November 28 (rh?=?0.0125 au). These observations reveal a rapidly varying dust environment in which the dust emission was initially point-like. As ISON approached perihelion, the continuum emission became an elongated dust column spread out over as much as 60? (greater than 10(exp 5) km in the anti-solar direction. Deconvolution of the November 28.04 850 microns image reveals numerous distinct clumps consistent with the catastrophic disruption of comet ISON, producing approximately 5.2?×?10(exp 10) kg of submillimeter-sized dust. Orbital computations suggest that the SCUBA-2 emission peak coincides with the comet's residual nucleus.

  4. Incumbent response to disruptive innovation

    DEFF Research Database (Denmark)

    Kaulio, Matti; Thorén, Kent; Rohrbeck, René

    in relation to disruptive change. In relation to technical change the case company has successfully in transferred its technology from one generation to the next during more than 20 years. In relation to business model change the case company has been proactive but not successful in major business model......This article presents a preliminary analysis of a retrospective longitudinal case study of an incumbent, the Swedish-Finnish Telecom operator TeliaSonera AB, with focus on its responses to technical and business model change. Findings nuance the general understanding of Telco’s as passive actors...... changes, however successful in minor business model adaptions. An implication hereof is that the business model concept as such has low predictive power in explaining success and failure and is in the need of an operationalization. In addition, the article discusses the relationship between technological...

  5. Automatic location of disruption times in JET

    Science.gov (United States)

    Moreno, R.; Vega, J.; Murari, A.

    2014-11-01

    The loss of stability and confinement in tokamak plasmas can induce critical events known as disruptions. Disruptions produce strong electromagnetic forces and thermal loads which can damage fundamental components of the devices. Determining the disruption time is extremely important for various disruption studies: theoretical models, physics-driven models, or disruption predictors. In JET, during the experimental campaigns with the JET-C (Carbon Fiber Composite) wall, a common criterion to determine the disruption time consisted of locating the time of the thermal quench. However, with the metallic ITER-like wall (JET-ILW), this criterion is usually not valid. Several thermal quenches may occur previous to the current quench but the temperature recovers. Therefore, a new criterion has to be defined. A possibility is to use the start of the current quench as disruption time. This work describes the implementation of an automatic data processing method to estimate the disruption time according to this new definition. This automatic determination allows both reducing human efforts to locate the disruption times and standardizing the estimates (with the benefit of being less vulnerable to human errors).

  6. Automatic location of disruption times in JET.

    Science.gov (United States)

    Moreno, R; Vega, J; Murari, A

    2014-11-01

    The loss of stability and confinement in tokamak plasmas can induce critical events known as disruptions. Disruptions produce strong electromagnetic forces and thermal loads which can damage fundamental components of the devices. Determining the disruption time is extremely important for various disruption studies: theoretical models, physics-driven models, or disruption predictors. In JET, during the experimental campaigns with the JET-C (Carbon Fiber Composite) wall, a common criterion to determine the disruption time consisted of locating the time of the thermal quench. However, with the metallic ITER-like wall (JET-ILW), this criterion is usually not valid. Several thermal quenches may occur previous to the current quench but the temperature recovers. Therefore, a new criterion has to be defined. A possibility is to use the start of the current quench as disruption time. This work describes the implementation of an automatic data processing method to estimate the disruption time according to this new definition. This automatic determination allows both reducing human efforts to locate the disruption times and standardizing the estimates (with the benefit of being less vulnerable to human errors).

  7. Disruptive colouration and perceptual grouping.

    Science.gov (United States)

    Espinosa, Irene; Cuthill, Innes C

    2014-01-01

    Camouflage is the primary defence of many animals and includes multiple strategies that interfere with figure-ground segmentation and object recognition. While matching background colours and textures is widespread and conceptually straightforward, less well explored are the optical 'tricks', collectively called disruptive colouration, that exploit perceptual grouping mechanisms. Adjacent high contrast colours create false edges, but this is not sufficient for an object's shape to be broken up; some colours must blend with the background. We test the novel hypothesis that this will be particularly effective when the colour patches on the animal appear to belong to, not merely different background colours, but different background objects. We used computer-based experiments where human participants had to find cryptic targets on artificial backgrounds. Creating what appeared to be bi-coloured foreground objects on bi-coloured backgrounds, we generated colour boundaries that had identical local contrast but either lay within or between (illusory) objects. As predicted, error rates for targets matching what appeared to be different background objects were higher than for targets which had otherwise identical local contrast to the background but appeared to belong to single background objects. This provides evidence for disruptive colouration interfering with higher-level feature integration in addition to previously demonstrated low-level effects involving contour detection. In addition, detection was impeded in treatments where targets were on or in close proximity to multiple background colour or tone boundaries. This is consistent with other studies which show a deleterious influence of visual 'clutter' or background complexity on search.

  8. Disruptive colouration and perceptual grouping.

    Directory of Open Access Journals (Sweden)

    Irene Espinosa

    Full Text Available Camouflage is the primary defence of many animals and includes multiple strategies that interfere with figure-ground segmentation and object recognition. While matching background colours and textures is widespread and conceptually straightforward, less well explored are the optical 'tricks', collectively called disruptive colouration, that exploit perceptual grouping mechanisms. Adjacent high contrast colours create false edges, but this is not sufficient for an object's shape to be broken up; some colours must blend with the background. We test the novel hypothesis that this will be particularly effective when the colour patches on the animal appear to belong to, not merely different background colours, but different background objects. We used computer-based experiments where human participants had to find cryptic targets on artificial backgrounds. Creating what appeared to be bi-coloured foreground objects on bi-coloured backgrounds, we generated colour boundaries that had identical local contrast but either lay within or between (illusory objects. As predicted, error rates for targets matching what appeared to be different background objects were higher than for targets which had otherwise identical local contrast to the background but appeared to belong to single background objects. This provides evidence for disruptive colouration interfering with higher-level feature integration in addition to previously demonstrated low-level effects involving contour detection. In addition, detection was impeded in treatments where targets were on or in close proximity to multiple background colour or tone boundaries. This is consistent with other studies which show a deleterious influence of visual 'clutter' or background complexity on search.

  9. Conversion of homothallic yeast to heterothallism through to gene disruption

    CSIR Research Space (South Africa)

    Van Zyl, WH

    1993-04-01

    Full Text Available ). DNA content. The cellular DNA of stationary-phase cells (5 x 109 cells per sample) was extracted with perchloric acid and the DNA content determined in duplicate according to the diphenylamine method described by Stewart (1975). Herring sperm DNA...

  10. Homology-integrated CRISPR-Cas (HI-CRISPR) system for one-step multigene disruption in Saccharomyces cerevisiae.

    Science.gov (United States)

    Bao, Zehua; Xiao, Han; Liang, Jing; Zhang, Lu; Xiong, Xiong; Sun, Ning; Si, Tong; Zhao, Huimin

    2015-05-15

    One-step multiple gene disruption in the model organism Saccharomyces cerevisiae is a highly useful tool for both basic and applied research, but it remains a challenge. Here, we report a rapid, efficient, and potentially scalable strategy based on the type II Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-CRISPR associated proteins (Cas) system to generate multiple gene disruptions simultaneously in S. cerevisiae. A 100 bp dsDNA mutagenizing homologous recombination donor is inserted between two direct repeats for each target gene in a CRISPR array consisting of multiple donor and guide sequence pairs. An ultrahigh copy number plasmid carrying iCas9, a variant of wild-type Cas9, trans-encoded RNA (tracrRNA), and a homology-integrated crRNA cassette is designed to greatly increase the gene disruption efficiency. As proof of concept, three genes, CAN1, ADE2, and LYP1, were simultaneously disrupted in 4 days with an efficiency ranging from 27 to 87%. Another three genes involved in an artificial hydrocortisone biosynthetic pathway, ATF2, GCY1, and YPR1, were simultaneously disrupted in 6 days with 100% efficiency. This homology-integrated CRISPR (HI-CRISPR) strategy represents a powerful tool for creating yeast strains with multiple gene knockouts.

  11. Criteria for initiation of tokamak disruptions

    International Nuclear Information System (INIS)

    Hopcraft, K.I.; Turner, M.F.

    1986-01-01

    The process by which a tokamak plasma evolves from an equilibrium state containing a saturated magnetic island to one which is disruptively unstable is discussed and illustrated by numerical simulation of a resistive magnetoplasma. Those elements which are required to initiate a disruption are delineated

  12. Disruption simulation for the EAST plasma

    International Nuclear Information System (INIS)

    Niu Xingping; Wu Bin

    2007-01-01

    The disruptions due to vertical displacement event for the EAST plasma are simulated in this article by using the TSC program. Meanwhile, the evolutions of the halo current and stress on vacuum vessel are calculated; the disruptions at different initial conditions are compared with each other, and killer pellet injection is simulated for the device fast shutting-down. (authors)

  13. Network Formation under the Threat of Disruption

    NARCIS (Netherlands)

    Hoyer, B.

    2013-01-01

    The studies in this thesis are focused on the impact the presence of a network disruptor has on network formation models. In particular, we build two theoretical models to study the effect of network disruption on network formation and test the effect network disruption has on equilibrium selection

  14. Inventory strategies to manage supply disruptions

    NARCIS (Netherlands)

    Atan, Z.; Snyder, L.V.; Gurnani, H.; Mehrotra, H.; Ray, S.

    2012-01-01

    Disruptions in supply chains occur routinely—both large ones, due to natural disasters, labor strikes, or terrorist attacks, and small ones, due to machine breakdowns, supplier stockouts, or quality problems (to name a few examples). Companies whose supply processes are affected by disruptions may

  15. Simulation of a major tokamak disruption

    International Nuclear Information System (INIS)

    White, R.B.; Monticello, D.A.; Rosenbluth, M.N.

    1977-08-01

    It is known that the internal tokamak disruption leads to a current profile which is flattened inside the surface where the safety factor equals unity. It is shown that such a profile can lead to m = 2 magnetic islands which grow to fill a substantial part of the tokamak cross section in a time consistent with the observations of the major disruption

  16. Disruptive technologies and networking in telecom industries

    DEFF Research Database (Denmark)

    Madsen, Erik Strøjer; Hartington, Simon

    in the telecommunication industry and finds significant similarities between the industry development and the literature on disruptive technology, which finds that incumbent companies are not able to react in a successful way when disruptions occur in their industry. By studying how the telecommunication industry...

  17. Disrupted Sleep: From Molecules to Cognition

    NARCIS (Netherlands)

    van Someren, E.J.; Cirelli, C.; Dijk, D.J.; Van Cauter, E.; Schwartz, S.; Chee, M.W.L.

    2015-01-01

    Although the functions of sleep remain to be fully elucidated, it is clear that there are far-reaching effects of its disruption, whether by curtailment for a single night, by a few hours each night over a long period, or by disruption in sleep continuity. Epidemiological and experimental studies of

  18. Disrupted Sleep : From Molecules to Cognition

    NARCIS (Netherlands)

    Van Someren, Eus J W; Cirelli, Chiara; Dijk, Derk-Jan; Van Cauter, Eve; Schwartz, Sophie; Chee, Michael W L

    2015-01-01

    UNLABELLED: Although the functions of sleep remain to be fully elucidated, it is clear that there are far-reaching effects of its disruption, whether by curtailment for a single night, by a few hours each night over a long period, or by disruption in sleep continuity. Epidemiological and

  19. Disruption Management in Passenger Railway Transportation

    DEFF Research Database (Denmark)

    Groth, Julie Jespersen; Potthoff, Daniel; Clausen, Jens

    2009-01-01

    This paper deals with disruption management in passenger railway transportation. In the disruption management process, many actors belonging to different organizations play a role. In this paper we therefore describe the process itself and the roles of the different actors. Furthermore, we discuss...

  20. Resistance to Disruption in a Classroom Setting

    Science.gov (United States)

    Parry-Cruwys, Diana E.; Neal, Carrie M.; Ahearn, William H.; Wheeler, Emily E.; Premchander, Raseeka; Loeb, Melissa B.; Dube, William V.

    2011-01-01

    Substantial experimental evidence indicates that behavior reinforced on a denser schedule is more resistant to disruption than is behavior reinforced on a thinner schedule. The present experiment studied resistance to disruption in a natural educational environment. Responding during familiar activities was reinforced on a multiple…

  1. Sideways wall force produced during tokamak disruptions

    Science.gov (United States)

    Strauss, H.; Paccagnella, R.; Breslau, J.; Sugiyama, L.; Jardin, S.

    2013-07-01

    A critical issue for ITER is to evaluate the forces produced on the surrounding conducting structures during plasma disruptions. We calculate the non-axisymmetric ‘sideways’ wall force Fx, produced in disruptions. Simulations were carried out of disruptions produced by destabilization of n = 1 modes by a vertical displacement event (VDE). The force depends strongly on γτwall, where γ is the mode growth rate and τwall is the wall penetration time, and is largest for γτwall = constant, which depends on initial conditions. Simulations of disruptions caused by a model of massive gas injection were also performed. It was found that the wall force increases approximately offset linearly with the displacement from the magnetic axis produced by a VDE. These results are also obtained with an analytical model. Disruptions are accompanied by toroidal variation of the plasma current Iφ. This is caused by toroidal variation of the halo current, as verified computationally and analytically.

  2. Towards a Framework of Digital Platform Disruption

    DEFF Research Database (Denmark)

    Kazan, Erol; Tan, Chee-Wee; Lim, Eric T. K.

    2014-01-01

    Digital platforms are disruptive information technology (IT) artifacts that erode conventional business logic associated with traditional market structures. This paper presents a framework for examining the disruptive potential of digital platforms whereby we postulate that the strategic interplay...... digital platforms purposely decouple platform layers, to foster open innovation and accelerate market disruption. This paper therefore represents a first concrete step aimed at unravelling the disruptive potential of digital platforms....... of governance regimes and platform layers is deterministic of whether disruptive derivatives are permitted to flourish. This framework has been employed in a comparative case study between centralized (i.e., PayPal) and decentralized (i.e., Coinkite) digital payment platforms to illustrate its applicability...

  3. Plasma membrane disruption: repair, prevention, adaptation

    Science.gov (United States)

    McNeil, Paul L.; Steinhardt, Richard A.

    2003-01-01

    Many metazoan cells inhabit mechanically stressful environments and, consequently, their plasma membranes are frequently disrupted. Survival requires that the cell rapidly repair or reseal the disruption. Rapid resealing is an active and complex structural modification that employs endomembrane as its primary building block, and cytoskeletal and membrane fusion proteins as its catalysts. Endomembrane is delivered to the damaged plasma membrane through exocytosis, a ubiquitous Ca2+-triggered response to disruption. Tissue and cell level architecture prevent disruptions from occurring, either by shielding cells from damaging levels of force, or, when this is not possible, by promoting safe force transmission through the plasma membrane via protein-based cables and linkages. Prevention of disruption also can be a dynamic cell or tissue level adaptation triggered when a damaging level of mechanical stress is imposed. Disease results from failure of either the preventive or resealing mechanisms.

  4. Genes and Gene Therapy

    Science.gov (United States)

    ... correctly, a child can have a genetic disorder. Gene therapy is an experimental technique that uses genes to ... or prevent disease. The most common form of gene therapy involves inserting a normal gene to replace an ...

  5. Disruption of the thyroid system by the thyroid-disrupting compound Aroclor 1254 in juvenile Japanese flounder (Paralichthys olivaceus.

    Directory of Open Access Journals (Sweden)

    Yifei Dong

    Full Text Available Polychlorinated biphenyls (PCBs are a group of persistent organochlorine compounds that have the potential to disrupt the homeostasis of thyroid hormones (THs in fish, particularly juveniles. In this study, thyroid histology, plasma TH levels, and iodothyronine deiodinase (IDs, including ID1, ID2, and ID3 gene expression patterns were examined in juvenile Japanese flounder (Paralichthys olivaceus following 25- and 50-day waterborne exposure to environmentally relevant concentrations of a commercial PCB mixture, Aroclor 1254 (10, 100, and 1000 ng/L with two-thirds of the test solutions renewed daily. The results showed that exposure to Aroclor 1254 for 50 d increased follicular cell height, colloid depletion, and hyperplasia. In particular, hypothyroidism, which was induced by the administration of 1000 ng/L Aroclor 1254, significantly decreased plasma TT4, TT3, and FT3 levels. Profiles of the changes in mRNA expression levels of IDs were observed in the liver and kidney after 25 and 50 d PCB exposure, which might be associated with a reduction in plasma THs levels. The expression level of ID2 mRNA in the liver exhibited a dose-dependent increase, indicating that this ID isotype might serve as sensitive and stable indicator for thyroid-disrupting chemical (TDC exposure. Overall, our study confirmed that environmentally relevant concentrations of Aroclor 1254 cause significant thyroid disruption, with juvenile Japanese flounder being suitable candidates for use in TDC studies.

  6. Microalgal cell disruption via ultrasonic nozzle spraying.

    Science.gov (United States)

    Wang, M; Yuan, W

    2015-01-01

    The objective of this study was to understand the effect of operating parameters, including ultrasound amplitude, spraying pressure, nozzle orifice diameter, and initial cell concentration on microalgal cell disruption and lipid extraction in an ultrasonic nozzle spraying system (UNSS). Two algal species including Scenedesmus dimorphus and Nannochloropsis oculata were evaluated. Experimental results demonstrated that the UNSS was effective in the disruption of microalgal cells indicated by significant changes in cell concentration and Nile red-stained lipid fluorescence density between all treatments and the control. It was found that increasing ultrasound amplitude generally enhanced cell disruption and lipid recovery although excessive input energy was not necessary for best results. The effect of spraying pressure and nozzle orifice diameter on cell disruption and lipid recovery was believed to be dependent on the competition between ultrasound-induced cavitation and spraying-generated shear forces. Optimal cell disruption was not always achieved at the highest spraying pressure or biggest nozzle orifice diameter; instead, they appeared at moderate levels depending on the algal strain and specific settings. Increasing initial algal cell concentration significantly reduced cell disruption efficiency. In all UNSS treatments, the effectiveness of cell disruption and lipid recovery was found to be dependent on the algal species treated.

  7. Prenatal PCBs disrupt early neuroendocrine development of the rat hypothalamus

    International Nuclear Information System (INIS)

    Dickerson, Sarah M.; Cunningham, Stephanie L.; Gore, Andrea C.

    2011-01-01

    Neonatal exposure to endocrine disrupting chemicals (EDCs) such as polychlorinated biphenyls (PCBs) can interfere with hormone-sensitive developmental processes, including brain sexual differentiation. We hypothesized that disruption of these processes by gestational PCB exposure would be detectable as early as the day after birth (postnatal day (P) 1) through alterations in hypothalamic gene and protein expression. Pregnant Sprague-Dawley rats were injected twice, once each on gestational days 16 and 18, with one of the following: DMSO vehicle; the industrial PCB mixture Aroclor 1221 (A1221); a reconstituted mixture of the three most prevalent congeners found in humans, PCB138, PCB153, and PCB180; or estradiol benzoate (EB). On P1, litter composition, anogenital distance (AGD), and body weight were assessed. Pups were euthanized for immunohistochemistry of estrogen receptor α (ERα) or TUNEL labeling of apoptotic cells or quantitative PCR of 48 selected genes in the preoptic area (POA). We found that treatment with EB or A1221 had a sex-specific effect on developmental apoptosis in the neonatal anteroventral periventricular nucleus (AVPV), a sexually dimorphic hypothalamic region involved in the regulation of reproductive neuroendocrine function. In this region, exposed females had increased numbers of apoptotic nuclei, whereas there was no effect of treatment in males. For ERα, EB treatment increased immunoreactive cell numbers and density in the medial preoptic nucleus (MPN) of both males and females, while A1221 and the PCB mixture had no effect. PCR analysis of gene expression in the POA identified nine genes that were significantly altered by prenatal EDC exposure, in a manner that varied by sex and treatment. These genes included brain-derived neurotrophic factor, GABA B receptors-1 and -2, IGF-1, kisspeptin receptor, NMDA receptor subunits NR2b and NR2c, prodynorphin, and TGFα. Collectively, these results suggest that the disrupted sexual differentiation

  8. Disruption of an Evolutionarily Novel Synaptic Expression Pattern in Autism

    Science.gov (United States)

    Jiang, Xi; Hu, Haiyang; Guijarro, Patricia; Mitchell, Amanda; Ely, John J.; Sherwood, Chet C.; Hof, Patrick R.; Qiu, Zilong; Pääbo, Svante; Akbarian, Schahram; Khaitovich, Philipp

    2016-01-01

    Cognitive defects in autism spectrum disorder (ASD) include socialization and communication: key behavioral capacities that separate humans from other species. Here, we analyze gene expression in the prefrontal cortex of 63 autism patients and control individuals, as well as 62 chimpanzees and macaques, from natal to adult age. We show that among all aberrant expression changes seen in ASD brains, a single aberrant expression pattern overrepresented in genes involved synaptic-related pathways is enriched in nucleotide variants linked to autism. Furthermore, only this pattern contains an excess of developmental expression features unique to humans, thus resulting in the disruption of human-specific developmental programs in autism. Several members of the early growth response (EGR) transcription factor family can be implicated in regulation of this aberrant developmental change. Our study draws a connection between the genetic risk architecture of autism and molecular features of cortical development unique to humans. PMID:27685936

  9. Disruption of an Evolutionarily Novel Synaptic Expression Pattern in Autism.

    Directory of Open Access Journals (Sweden)

    Xiling Liu

    2016-09-01

    Full Text Available Cognitive defects in autism spectrum disorder (ASD include socialization and communication: key behavioral capacities that separate humans from other species. Here, we analyze gene expression in the prefrontal cortex of 63 autism patients and control individuals, as well as 62 chimpanzees and macaques, from natal to adult age. We show that among all aberrant expression changes seen in ASD brains, a single aberrant expression pattern overrepresented in genes involved synaptic-related pathways is enriched in nucleotide variants linked to autism. Furthermore, only this pattern contains an excess of developmental expression features unique to humans, thus resulting in the disruption of human-specific developmental programs in autism. Several members of the early growth response (EGR transcription factor family can be implicated in regulation of this aberrant developmental change. Our study draws a connection between the genetic risk architecture of autism and molecular features of cortical development unique to humans.

  10. Sleep and circadian rhythm disruption in neuropsychiatric illness.

    Science.gov (United States)

    Jagannath, Aarti; Peirson, Stuart N; Foster, Russell G

    2013-10-01

    Sleep and circadian rhythm disruption (SCRD) is a common feature in many neuropsychiatric diseases including schizophrenia, bipolar disorder and depression. Although the precise mechanisms remain unclear, recent evidence suggests that this comorbidity is not simply a product of medication or an absence of social routine, but instead reflects commonly affected underlying pathways and mechanisms. For example, several genes intimately involved in the generation and regulation of circadian rhythms and sleep have been linked to psychiatric illness. Further, several genes linked to mental illness have recently been shown to also play a role in normal sleep and circadian behaviour. Here we describe some of the emerging common mechanisms that link circadian rhythms, sleep and SCRD in severe mental illnesses. A deeper understanding of these links will provide not only a greater understanding of disease mechanisms, but also holds the promise of novel avenues for therapeutic intervention. Copyright © 2013. Published by Elsevier Ltd.

  11. Enhancement of L-cysteine production by disruption of yciW in Escherichia coli.

    Science.gov (United States)

    Kawano, Yusuke; Ohtsu, Iwao; Takumi, Kazuhiro; Tamakoshi, Ai; Nonaka, Gen; Funahashi, Eri; Ihara, Masaki; Takagi, Hiroshi

    2015-02-01

    Using in silico analysis, the yciW gene of Escherichia coli was identified as a novel L-cysteine regulon that may be regulated by the transcriptional activator CysB for sulfur metabolic genes. We found that overexpression of yciW conferred tolerance to L-cysteine, but disruption of yciW increased L-cysteine production in E. coli. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  12. Integrated data analysis reveals potential drivers and pathways disrupted by DNA methylation in papillary thyroid carcinomas

    DEFF Research Database (Denmark)

    Beltrami, Caroline Moraes; Dos Reis, Mariana Bisarro; Barros-Filho, Mateus Camargo

    2017-01-01

    and positive correlation, respectively. Genes showing negative correlation underlined FGF and retinoic acid signaling as critical canonical pathways disrupted by DNA methylation in PTC. BRAF mutation was detected in 68% (28 of 41) of the tumors, which presented a higher level of demethylation (95...

  13. Erosion products in disruption simulation experiments

    International Nuclear Information System (INIS)

    Safronov, V.; Arkhipov, N.; Bakhtin, V.; Barsuk, V.; Kurkin, S.; Mironova, E.; Toporkov, D.; Vasenin, S.; Zhitlukhin, A.; Arkhipov, I.; Werle, H.; Wuerz, H.

    1998-01-01

    Erosion of divertor materials under tokamak disruption event presents a serious problem of ITER technology. Erosion restricts the divertor lifetime and leads to production of redeposited layers of the material retaining large amount of tritium, which is a major safety issue for future fusion reactor. Since ITER disruptive heat loads are not achievable in existing tokamaks, material erosion is studied in special simulation experiments. Till now the simulation experiments have focused mainly on investigation of shielding effect and measurement of erosion rate. In the present work the properties of eroded and redeposited graphite are studied under condition typical for hard ITER disruption. (author)

  14. Disruptions and Their Mitigation in TEXTOR

    International Nuclear Information System (INIS)

    Finken, K.H.; Jaspers, R.; Kraemer-Flecken, A.; Savtchkov, A.; Lehnen, M.; Waidmann, G.

    2005-01-01

    Disruptions remain a major concern for tokamak devices, particularly for large machines. The critical issues are the induced (halo) currents and the resulting forces, the excessive heating of exposed surfaces by the instantaneous power release, and the possible occurrence of highly energetic runaway electrons. The key topics of the investigations on TEXTOR in the recent years concerned (a) the power deposition pattern recorded by a fast infrared scanner, (b) the runaway generation measured by synchrotron radiation in the infrared spectral region, (c) method development for 'healing' discharges that are going to disrupt, and (d) massive gas puffing for mitigating the adverse effects of disruptions

  15. Visual in-pile fuel disruption experiments

    International Nuclear Information System (INIS)

    Cano, G.L.; Ostensen, R.W.; Young, M.F.

    1978-01-01

    In a loss-of-flow (LOF) accident in an LMFBR, the mode of disruption of fuel may determine the probability of a subsequent energetic excursion. To investigate these phenomena, in-pile disruption of fission-heated irradiated fuel pellets was recorded by high speed cinematography. Instead of fuel frothing or dust-cloud breakup (as used in the SAS code) massive and very rapid fuel swelling, not predicted by analytical models, occurred. These tests support massive fuel swelling as the initial mode of fuel disruption in a LOF accident. (author)

  16. Periodic disruptions in the MT-1 tokamak

    International Nuclear Information System (INIS)

    Zoletnik, S.

    1988-11-01

    Disruptive instabilities are common phenomena in toroidal devices, especially in tokamaks. Three types can be distinguished: internal, minor and major disruptions. Periodic minor disruptions in the MT-1 tokamak were measured systematically with values of the limiter safety factor between 4 and 10. The density limit as a function of plasma current and horizontal displacement was investigated. Precursor oscillations always appear before the instability with increasing amplitude but can be observed at the density limit with quasi-stationary amplitude. Phase correlation between precursor oscillations were measured with Mirnov coils and x-ray detectors, and they show good agreement with a simple magnetic island model. (R.P.) 11 refs.; 6 figs

  17. Disruptive School Peers and Student Outcomes

    DEFF Research Database (Denmark)

    Kristoffersen, Jannie H. G.; Krægpøth, Morten; Nielsen, Helena Skyt

    2015-01-01

    This paper estimates how peers’ achievement gains are affected by the presence of potentially disruptive and emotionally sensitive children in the school-cohort. We exploit that some children move between schools and thus generate variation in peer composition in the receiving school-cohort. We...... identify three groups of potentially disruptive and emotionally sensitive children from detailed Danish register data: children with divorced parents, children with parents convicted of crime, and children with a psychiatric diagnosis. We find that adding potentially disruptive children lowers the academic...

  18. Disruptive School Peers and Student Outcomes

    DEFF Research Database (Denmark)

    Kristoffersen, Jannie H. Grøne; Krægpøth, Morten; Nielsen, Helena Skyt

    This paper estimates how peers’ achievement gains are affected by the presence of potentially disruptive and emotionally sensitive children in the school-cohort. We exploit that some children move between schools and thus generate variation in peer composition in the receiving school-cohort. We...... identify three groups of potentially disruptive and emotionally sensitive children from detailed Danish register data: children with divorced parents, children with parents convicted of crime, and children with a psychiatric diagnosis. We find that adding potentially disruptive children lowers the academic...

  19. Disruptive School Peers and Student Outcomes

    DEFF Research Database (Denmark)

    Kristoffersen, Jannie H. G.; Krægpøth, Morten Visby; Skyt Nielsen, Helena

    This paper estimates how peers’ achievement gains are affected by the presence of potentially disruptive and emotionally sensitive children in the school-cohort. We exploit that some children move between schools and thus generate variation in peer composition in the receiving schoolcohort. We...... identify three groups of potentially disruptive and emotionally sensitive children from detailed Danish register data: children with divorced parents, children with parents convicted of crime, and children with a psychiatric diagnosis. We find that adding potentially disruptive children lowers the academic...

  20. Glaciological parameters of disruptive event analysis

    International Nuclear Information System (INIS)

    Bull, C.

    1979-01-01

    The following disruptive events caused by ice sheets are considered: continental glaciation, erosion, loading and subsidence, deep ground water recharge, flood erosion, isostatic rebound rates, melting, and periodicity of ice ages

  1. Disruptive Innovation in Chinese and Indian Businesses

    DEFF Research Database (Denmark)

    markets, has made these emerging economies fertile ground for developing and applying disruptive innovations. A novel mix of key attributes distinctive from those of established technologies or business models, disruptive innovations are typically inferior, yet affordable and "good-enough" products...... or services, which originate in lower-end market segments, but later move up to compete with those provided by incumbent firms. This book sheds new light on disruptive innovations both from and for the bottom of the pyramid in China and India, from the point of view of local entrepreneurs and international...... firms seeking to operate their businesses there. It covers both the theoretical and practical implications of disruptive innovation using conceptual frameworks alongside detailed case studies, whilst also providing a comparison of conditions and strategic options in India and China. Further, unlike...

  2. Disruption mitigation studies in DIII-D

    International Nuclear Information System (INIS)

    Taylor, P.L.; Kellman, A.G.; Evans, T.E.

    1999-01-01

    Data on the discharge behavior, thermal loads, halo currents, and runaway electrons have been obtained in disruptions on the DIII-D tokamak. These experiments have also evaluated techniques to mitigate the disruptions while minimizing runaway electron production. Experiments injecting cryogenic impurity killer pellets of neon and argon and massive amounts of helium gas have successfully reduced these disruption effects. The halo current generation, scaling, and mitigation are understood and are in good agreement with predictions of a semianalytic model. Results from killer pellet injection have been used to benchmark theoretical models of the pellet ablation and energy loss. Runaway electrons are often generated by the pellets and new runaway generation mechanisms, modifications of the standard Dreicer process, have been found to explain the runaways. Experiments with the massive helium gas puff have also effectively mitigated disruptions without the formation of runaway electrons that can occur with killer pellets

  3. Runaway electron generation in tokamak disruptions

    International Nuclear Information System (INIS)

    Helander, P.; Andersson, F.; Fueloep, T.; Smith, H.; Anderson, D.; Lisak, M.; Eriksson, L.-G.

    2005-01-01

    The time evolution of the plasma current during a tokamak disruption is calculated by solving the equations for runaway electron production simultaneously with the induction equation for the toroidal electric field. The resistive diffusion time in a post-disruption plasma is typically comparable to the runaway avalanche growth time. Accordingly, the toroidal electric field induced after the thermal quench of a disruption diffuses radially through the plasma at the same time as it accelerates runaway electrons, which in turn back-react on the electric field. When these processes are accounted for in a self-consistent way, it is found that (1) the efficiency and time scale of runaway generation agrees with JET experiments; (2) the runaway current profile typically becomes more peaked than the pre-disruption current profile; and (3) can easily become radially filamented. It is also shown that higher runaway electron generation is expected if the thermal quench is sufficiently fast. (author)

  4. Disrupted functional brain networks in autistic toddlers

    NARCIS (Netherlands)

    Boersma, M.; Kemner, C.; Reus, M.A. de; Collin, G; Snijders, T.M.; Hofman, D.; Buitelaar, J.K.; Stam, C.J.; Heuvel, M.P. van den

    2013-01-01

    Communication and integration of information between brain regions plays a key role in healthy brain function. Conversely, disruption in brain communication may lead to cognitive and behavioral problems. Autism is a neurodevelopmental disorder that is characterized by impaired social interactions

  5. Integrated disruption avoidance and mitigation in KSTAR

    International Nuclear Information System (INIS)

    Kim, Jayhyun; Woo, M.H.; Han, H.; In, Y.; Bak, J.G.; Eidietis, N.W.

    2014-01-01

    The final target of Korea Superconducting Tokamak Advanced Research (KSTAR) aims advanced tokamak operation at plasma current 2 MA and toroidal field 3.5 T. In order to safely achieve the target, disruption counter-measures are unavoidable when considering the disruption risks, inevitably accompanied with high performance discharges, such as electro-magnetic load on conducting structures, collisional damage by run-away electrons, and thermal load on plasma facing components (PFCs). In this reason, the establishment of integrated disruption mitigation system (DMS) has been started for routine mega-ampere class operations of KSTAR since 2013 campaign. The DMS mainly consists of the disruption prediction and its avoidance/mitigation in company with logical/technical integration of them. We present the details of KSTAR DMS and the related experimental results in this article. (author)

  6. Disruption Management in Passenger Railway Transportation

    DEFF Research Database (Denmark)

    Jespersen-Groth, Julie; Potthoff, Daniel; Clausen, Jens

    This paper deals with disruption management in passenger railway transportation. In the disruption management process, many actors belonging to different organizations play a role. In this paper we therefore describe the process itself and the roles of the different actors. Furthermore, we discuss...... the three main subproblems in railway disruption management: timetable adjustment, and rolling stock and crew re-scheduling. Next to a general description of these problems, we give an overview of the existing literature and we present some details of the specific situations at DSB S-tog and NS....... These are the railway operators in the suburban area of Copenhagen, Denmark, and on the main railway lines in the Netherlands, respectively. Since not much research has been carried out yet on Operations Research models for disruption management in the railway context, models and techniques that have been developed...

  7. The Logic of Digital Platform Disruption

    DEFF Research Database (Denmark)

    Kazan, Erol; Tan, Chee-Wee; Lim, Eric T. K.

    Digital platforms are disruptive IT artifacts, because they facilitate the quick release of innovative platform derivatives from third parties (e.g., apps). This study endeavours to unravel the disruptive potential, caused by distinct designs and configurations of digital platforms on market...... environments. We postulate that the disruptive potential of digital platforms is determined by the degree of alignment among the business, technology and platform profiles. Furthermore, we argue that the design and configuration of the aforementioned three elements dictates the extent to which open innovation...... is permitted. To shed light on the disruptive potential of digital platforms, we opted for payment platforms as our unit of analysis. Through interviews with experts and payment providers, we seek to gain an in-depth appreciation of how contemporary digital payment platforms are designed and configured...

  8. Resonant Tidal Disruption in Galactic Nuclei

    OpenAIRE

    Rauch, Kevin P.; Ingalls, Brian

    1997-01-01

    It has recently been shown that the rate of angular momentum relaxation in nearly-Keplerian star clusters is greatly increased by a process termed resonant relaxation (Rauch & Tremaine 1996), who also argued that tidal disruption of stars in galactic nuclei containing massive black holes could be noticeably enhanced by this process. We describe here the results of numerical simulations of resonant tidal disruption which quantitatively test the predictions made by Rauch & Tremaine. The simulat...

  9. Disruptions, loads, and dynamic response of ITER

    International Nuclear Information System (INIS)

    Nelson, B.; Riemer, B.; Sayer, R.; Strickler, D.; Barabaschi, P.; Ioki, K.; Johnson, G.; Shimizu, K.; Williamson, D.

    1995-01-01

    Plasma disruptions and the resulting electromagnetic loads are critical to the design of the vacuum vessel and in-vessel components of the International Thermonuclear Experimental Reactor (ITER). This paper describes the status of plasma disruption simulations and related analysis, including the dynamic response of the vacuum vessel and in-vessel components, stresses and deflections in the vacuum vessel, and reaction loads in the support structures

  10. BUSINESS MODEL PATTERNS FOR DISRUPTIVE TECHNOLOGIES

    OpenAIRE

    BENJAMIN AMSHOFF; CHRISTIAN DÜLME; JULIAN ECHTERFELD; JÜRGEN GAUSEMEIER

    2015-01-01

    Companies nowadays face a myriad of business opportunities as a direct consequence of manifold disruptive technology developments. As a basic characteristic, disruptive technologies lead to a severe shift in value-creation networks giving rise to new market segments. One of the key challenges is to anticipate the business logics within these nascent and formerly unknown markets. Business model patterns promise to tackle this challenge. They can be interpreted as proven business model elements...

  11. Disruption of Core Planar Cell Polarity Signaling Regulates Renal Tubule Morphogenesis but Is Not Cystogenic.

    Science.gov (United States)

    Kunimoto, Koshi; Bayly, Roy D; Vladar, Eszter K; Vonderfecht, Tyson; Gallagher, Anna-Rachel; Axelrod, Jeffrey D

    2017-10-23

    Oriented cell division (OCD) and convergent extension (CE) shape developing renal tubules, and their disruption has been associated with polycystic kidney disease (PKD) genes, the majority of which encode proteins that localize to primary cilia. Core planar cell polarity (PCP) signaling controls OCD and CE in other contexts, leading to the hypothesis that disruption of PCP signaling interferes with CE and/or OCD to produce PKD. Nonetheless, the contribution of PCP to tubulogenesis and cystogenesis is uncertain, and two major questions remain unanswered. Specifically, the inference that mutation of PKD genes interferes with PCP signaling is untested, and the importance of PCP signaling for cystogenic PKD phenotypes has not been examined. We show that, during proliferative stages, PCP signaling polarizes renal tubules to control OCD. However, we find that, contrary to the prevailing model, PKD mutations do not disrupt PCP signaling but instead act independently and in parallel with PCP signaling to affect OCD. Indeed, PCP signaling that is normally downregulated once development is completed is retained in cystic adult kidneys. Disrupting PCP signaling results in inaccurate control of tubule diameter, a tightly regulated parameter with important physiological ramifications. However, we show that disruption of PCP signaling is not cystogenic. Our results suggest that regulating tubule diameter is a key function of PCP signaling but that loss of this control does not induce cysts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. BINARY DISRUPTION BY MASSIVE BLACK HOLES: HYPERVELOCITY STARS, S STARS, AND TIDAL DISRUPTION EVENTS

    Energy Technology Data Exchange (ETDEWEB)

    Bromley, Benjamin C. [Department of Physics and Astronomy, University of Utah, 115 S 1400 E, Rm 201, Salt Lake City, UT 84112 (United States); Kenyon, Scott J.; Geller, Margaret J.; Brown, Warren R., E-mail: bromley@physics.utah.edu, E-mail: skenyon@cfa.harvard.edu, E-mail: mgeller@cfa.harvard.edu, E-mail: wbrown@cfa.harvard.edu [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States)

    2012-04-20

    We examine whether disrupted binary stars can fuel black hole growth. In this mechanism, tidal disruption produces a single hypervelocity star (HVS) ejected at high velocity and a former companion star bound to the black hole. After a cluster of bound stars forms, orbital diffusion allows the black hole to accrete stars by tidal disruption at a rate comparable to the capture rate. In the Milky Way, HVSs and the S star cluster imply similar rates of 10{sup -5} to 10{sup -3} yr{sup -1} for binary disruption. These rates are consistent with estimates for the tidal disruption rate in nearby galaxies and imply significant black hole growth from disrupted binaries on 10 Gyr timescales.

  13. Mechanistic evaluation of endocrine disrupting chemicals

    DEFF Research Database (Denmark)

    Taxvig, Camilla

    BACKGROUND: This PhD project is part of the research area concerning effects of endocrine disrupters at the National Food Institute at DTU in Denmark. Endocrine disrupting chemicals (EDCs) have proved to be important for improper development of the male reproductive organs and subsequent for the ...... metabolising system using liver S9 mixtures or hepatic rat microsomes could be a convenient method for the incorporation of metabolic aspects into in vitro testing for endocrine disrupting effects.......BACKGROUND: This PhD project is part of the research area concerning effects of endocrine disrupters at the National Food Institute at DTU in Denmark. Endocrine disrupting chemicals (EDCs) have proved to be important for improper development of the male reproductive organs and subsequent......, to be able to detect effects and predict mixture effects. In addition, a new hypothesis have emerge concerning a potential role of exposure to endocrine disrupting chemicals, and the development of obesity and obesity related diseases. AIM: This PhD project aimed to gain more information regarding...

  14. Disruption modeling in support of ITER

    International Nuclear Information System (INIS)

    Bandyopadhyay, I.

    2015-01-01

    Plasma current disruptions and Vertical Displacement Events (VDEs) are one of the major concerns in any tokamak as they lead to large electromagnetic forces to tokamak first wall components and vacuum vessel. Their occurrence also means disruption to steady state operations of tokamaks. Thus future fusion reactors like ITER must ensure that disruptions and VDEs are minimized. However, since there is still finite probability of their occurrence, one must be able to characterize disruptions and VDEs and able to predict, for example, the plasma current quench time and halo current amplitude, which mainly determine the magnitude of the electromagnetic forces. There is a concerted effort globally to understand and predict plasma and halo current evolution during disruption in tokamaks through MHD simulations. Even though Disruption and VDEs are often 3D MHD perturbations in nature, presently they are mostly simulated using 2D axisymmetric MHD codes like the Tokamak Simulation Code (TSC) and DINA. These codes are also extensively benchmarked against experimental data in present day tokamaks to improve these models and their ability to predict these events in ITER. More detailed 3D models like M3D are only recently being developed, but they are yet to be benchmarked against experiments, as also they are massively computationally exhaustive

  15. MHD stability, operational limits and disruptions

    International Nuclear Information System (INIS)

    1999-01-01

    The present physics understandings of magnetohydrodynamic (MHD) stability of tokamak plasmas, the threshold conditions for onset of MHD instability, and the resulting operational limits on attainable plasma pressure (beta limit) and density (density limit), and the consequences of plasma disruption and disruption related effects are reviewed and assessed in the context of their application to a future DT burning reactor prototype tokamak experiment such as ITER. The principal considerations covered within the MHD stability and beta limit assessments are (i) magnetostatic equilibrium, ideal MHD stability and the resulting ideal MHD beta limit; (ii) sawtooth oscillations and the coupling of sawtooth activity to other types of MHD instability; (iii) neoclassical island resistive tearing modes and the corresponding limits on beta and energy confinement; (iv) wall stabilization of ideal MHD instabilities and resistive wall instabilities; (v) mode locking effects of non-axisymmetric error fields; (vi) edge localized MHD instabilities (ELMs, etc.); and (vii) MHD instabilities and beta/pressure gradient limits in plasmas with actively modified current and magnetic shear profiles. The principal considerations covered within the density limit assessments are (i) empirical density limits; (ii) edge power balance/radiative density limits in ohmic and L-mode plasmas; and (iii) edge parameter related density limits in H-mode plasmas. The principal considerations covered in the disruption assessments are (i) disruption causes, frequency and MHD instability onset; (ii) disruption thermal and current quench characteristics; (iii) vertical instabilities (VDEs), both before and after disruption, and plasma and in-vessel halo currents; (iv) after disruption runaway electron formation, confinement and loss; (v) fast plasma shutdown (rapid externally initiated dissipation of plasma thermal and magnetic energies); (vi) means for disruption avoidance and disruption effect mitigation; and

  16. Childhood trajectories of anxiousness and disruptiveness as predictors of suicide attempts.

    Science.gov (United States)

    Brezo, Jelena; Barker, Edward D; Paris, Joel; Hébert, Martine; Vitaro, Frank; Tremblay, Richard E; Turecki, Gustavo

    2008-11-01

    To investigate the association of childhood trajectories of anxiousness and disruptiveness with suicide attempts in early adulthood. Prospective cohort study. Public francophone schools in Quebec, Canada, from the 1986 to 1988 school years. Of 4,488 French Canadian children attending kindergarten, a representative group of 1,001 boys and 999 girls was chosen for follow-up. Of these, 1,144 individuals participated in the study during early adulthood. Suicide attempt histories by early adulthood, adjusted odds ratios (ORs) associated with membership in high- vs low-risk trajectories of anxiousness and disruptiveness, moderation (by sex), and mediation (by adolescent Axis I disorders). We observed 4 distinct developmental profiles of anxiousness and disruptiveness and a frequent co-occurrence of similar levels of these traits. In contrast to anxiousness trajectories (OR = 1.60; 95% confidence interval, 1.00-2.65), disruptiveness (OR = 1.80; 95% confidence interval, 1.03-3.13) and joint (OR = 1.88; 95% confidence interval, 1.05-3.37) trajectories made statistically significant contributions to suicide attempts. We found no support for mediation by adolescent anxiety/mood or disruptive disorders. Sex, however, moderated the effect of joint trajectories, increasing the risk of suicide attempts in women (OR = 3.60; Wald chi(2) = 10.93; P anxious and disruptive traits as children. Anxious-disruptive girls and disruptive boys appear to be more likely than their peers to attempt suicide by early adulthood. Preventive efforts will require more research into the possible mechanisms behind this early sex difference, ie, gene-environment interplays and nonpsychiatric mediators.

  17. Maintenance of a genetic polymorphism with disruptive natural selection in stickleback.

    Science.gov (United States)

    Marchinko, Kerry B; Matthews, Blake; Arnegard, Matthew E; Rogers, Sean M; Schluter, Dolph

    2014-06-02

    The role of natural selection in the maintenance of genetic variation in wild populations remains a major problem in evolution. The influence of disruptive natural selection on genetic variation is especially interesting because it might lead to the evolution of assortative mating or dominance [1, 2]. In theory, variation can persist at a gene under disruptive natural selection, but the process is little studied and there are few examples [3, 4]. We report a stable polymorphism in the bony armor of threespine stickleback maintained with a deficit of heterozygotes at the major underlying gene, Ectodysplasin (Eda) [5]. The deficit vanishes at the embryo life stage only to re-emerge in adults, indicating that disruptive natural selection, rather than nonrandom mating, is the cause. The mechanism enabling long-term persistence of the polymorphism is unknown, but disruptive selection is predicted to be frequency dependent, favoring homozygous genotypes when they become rare. Further research on the ecological and evolutionary processes affecting individual genes will ultimately lead to a better understanding of the causes of genetic variation in populations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. An overproduction of astellolides induced by genetic disruption of chromatin-remodeling factors in Aspergillus oryzae.

    Science.gov (United States)

    Shinohara, Yasutomo; Kawatani, Makoto; Futamura, Yushi; Osada, Hiroyuki; Koyama, Yasuji

    2016-01-01

    The filamentous fungus Aspergillus oryzae is an important industrial mold. Recent genomic analysis indicated that A. oryzae has a large number of biosynthetic genes for secondary metabolites (SMs), but many of the SMs they produce have not been identified. For better understanding of SMs production by A. oryzae, we screened a gene-disruption library of transcription factors including chromatin-remodeling factors and found two gene disruptions that show similarly altered SM production profiles. One is a homolog of Aspergillus nidulans cclA, a component of the histone 3 lysine 4 (H3K4) methyltransferase complex of proteins associated with Set1 complex, and the other, sppA, is an ortholog of Saccharomyces cerevisiae SPP1, another component of a complex of proteins associated with Set1 complex. The cclA and sppA disruptions in A. oryzae are deficient in trimethylation of H3K4. Furthermore, one of the SMs that increased in the cclA disruptant was identified as astellolide F (14-deacetyl astellolide B). These data indicate that both cclA and sppA affect production of SMs including astellolides by affecting the methylation status of H3K4 in A. oryzae.

  19. Epistatic and Independent Effects on Schizophrenia-Related Phenotypes Following Co-disruption of the Risk Factors Neuregulin-1 × DISC1.

    Science.gov (United States)

    O'Tuathaigh, Colm M P; Fumagalli, Fabio; Desbonnet, Lieve; Perez-Branguli, Francesc; Moloney, Gerard; Loftus, Samim; O'Leary, Claire; Petit, Emilie; Cox, Rachel; Tighe, Orna; Clarke, Gerard; Lai, Donna; Harvey, Richard P; Cryan, John F; Mitchell, Kevin J; Dinan, Timothy G; Riva, Marco A; Waddington, John L

    2017-01-01

    Few studies have addressed likely gene × gene (ie, epistatic) interactions in mediating risk for schizophrenia. Using a preclinical genetic approach, we investigated whether simultaneous disruption of the risk factors Neuregulin-1 (NRG1) and Disrupted-in-schizophrenia 1 (DISC1) would produce a disease-relevant phenotypic profile different from that observed following disruption to either gene alone. NRG1 heterozygotes exhibited hyperactivity and disruption to prepulse inhibition, both reversed by antipsychotic treatment, and accompanied by reduced striatal dopamine D2 receptor protein expression, impaired social cognition, and altered glutamatergic synaptic protein expression in selected brain areas. Single gene DISC1 mutants demonstrated a disruption in social cognition and nest-building, altered brain 5-hydroxytryptamine levels and hippocampal ErbB4 expression, and decreased cortical expression of the schizophrenia-associated microRNA miR-29b. Co-disruption of DISC1 and NRG1, indicative of epistasis, evoked an impairment in sociability and enhanced self-grooming, accompanied by changes in hypothalamic oxytocin/vasopressin gene expression. The findings indicate specific behavioral correlates and underlying cellular pathways downstream of main effects of DNA variation in the schizophrenia-associated genes NRG1 and DISC1. © The Author 2016. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  20. Endocrine Disrupting Contaminants—Beyond the Dogma

    Science.gov (United States)

    Guillette, Louis J.

    2006-01-01

    Descriptions of endocrine disruption have largely been associated with wildlife and driven by observations documenting estrogenic, androgenic, antiandrogenic, and antithyroid actions. These actions, in response to exposure to ecologically relevant concentrations of various environmental contaminants, have now been established in numerous vertebrate species. However, many potential mechanisms and endocrine actions have not been studied. For example, the DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane] metabolite, p,p′-DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene] is known to disrupt prostaglandin synthesis in the uterus of birds, providing part of the explanation for DDT-induced egg shell thinning. Few studies have examined prostaglandin synthesis as a target for endocrine disruption, yet these hormones are active in reproduction, immune responses, and cardiovascular physiology. Future studies must broaden the basic science approach to endocrine disruption, thereby expanding the mechanisms and endocrine end points examined. This goal should be accomplished even if the primary influence and funding continue to emphasize a narrower approach based on regulatory needs. Without this broader approach, research into endocrine disruption will become dominated by a narrow dogma, focusing on a few end points and mechanisms. PMID:16818240

  1. Effect of music on mealtime disruptions.

    Science.gov (United States)

    Hooper, Jeff; Carson, Derek; Lindsay, Bill

    People with learning disabilities can disrupt mealtimes with non-cooperative, aggressive and self-injurious behaviours that challenge other people to tolerate and manage them. These behaviours appear to arise because the proximity of other people, and the heightened activity and noise of a dining room, causes anxiety and agitation. To examine how delivering calming background music via headphones affected anxiety-driven behaviours that disrupted mealtimes. A sample of 30 adults with mild, moderate or severe learning disabilities were videotaped during mealtimes on two consecutive days. On the first day, half the group ate without any calming music while the other half sat opposite them wearing earphones and listening to calming music. On the second day, the non-music and music groups swapped around. Of the participants who tolerated the earphones, only three showed disruptive behaviour; all three had been sitting at the table waiting for their food. With so few examples, meaningful inferential analysis was not possible. However, there were signs that calming music had a positive effect on disruptive mealtime behaviours. It eliminated physical harm, complaining and verbal repetition in one person, and stopped another from shouting/swearing. It also reduced the incidence of shouting/swearing, restlessness and vocalising. Calming music and reduced waiting at tables for food may reduce disruptive behaviours.

  2. Disruptive Intelligence - How to gather Information to deal with disruptive innovations

    NARCIS (Netherlands)

    Vriens, D.J.; Solberg Søilen, K.

    2014-01-01

    Disruptive innovations are innovations that have the capacity to transform a whole business into one with products that are more accessible and affordable (cf. Christensen et al. 2009). As Christensen et al. argue no business is immune to such disruptive innovations. If these authors are right, it

  3. Disruption of Trichoderma reesei cre2, encoding an ubiquitin C-terminal hydrolase, results in increased cellulase activity

    Science.gov (United States)

    2011-01-01

    Background The filamentous fungus Trichoderma reesei (Hypocrea jecorina) is an important source of cellulases for use in the textile and alternative fuel industries. To fully understand the regulation of cellulase production in T. reesei, the role of a gene known to be involved in carbon regulation in Aspergillus nidulans, but unstudied in T. reesei, was investigated. Results The T. reesei orthologue of the A. nidulans creB gene, designated cre2, was identified and shown to be functional through heterologous complementation of a creB mutation in A. nidulans. A T. reesei strain was constructed using gene disruption techniques that contained a disrupted cre2 gene. This strain, JKTR2-6, exhibited phenotypes similar to the A. nidulans creB mutant strain both in carbon catabolite repressing, and in carbon catabolite derepressing conditions. Importantly, the disruption also led to elevated cellulase levels. Conclusions These results demonstrate that cre2 is involved in cellulase expression. Since the disruption of cre2 increases the amount of cellulase activity, without severe morphological affects, targeting creB orthologues for disruption in other industrially useful filamentous fungi, such as Aspergillus oryzae, Trichoderma harzianum or Aspergillus niger may also lead to elevated hydrolytic enzyme activity in these species. PMID:22070776

  4. Disruption of Trichoderma reesei cre2, encoding an ubiquitin C-terminal hydrolase, results in increased cellulase activity

    Directory of Open Access Journals (Sweden)

    Denton Jai A

    2011-11-01

    Full Text Available Abstract Background The filamentous fungus Trichoderma reesei (Hypocrea jecorina is an important source of cellulases for use in the textile and alternative fuel industries. To fully understand the regulation of cellulase production in T. reesei, the role of a gene known to be involved in carbon regulation in Aspergillus nidulans, but unstudied in T. reesei, was investigated. Results The T. reesei orthologue of the A. nidulans creB gene, designated cre2, was identified and shown to be functional through heterologous complementation of a creB mutation in A. nidulans. A T. reesei strain was constructed using gene disruption techniques that contained a disrupted cre2 gene. This strain, JKTR2-6, exhibited phenotypes similar to the A. nidulans creB mutant strain both in carbon catabolite repressing, and in carbon catabolite derepressing conditions. Importantly, the disruption also led to elevated cellulase levels. Conclusions These results demonstrate that cre2 is involved in cellulase expression. Since the disruption of cre2 increases the amount of cellulase activity, without severe morphological affects, targeting creB orthologues for disruption in other industrially useful filamentous fungi, such as Aspergillus oryzae, Trichoderma harzianum or Aspergillus niger may also lead to elevated hydrolytic enzyme activity in these species.

  5. Mechanical algal disruption for efficient biodiesel extraction

    Science.gov (United States)

    Krehbiel, Joel David

    Biodiesel from algae provides several benefits over current biodiesel feedstocks, but the energy requirements of processing algae into a useable fuel are currently so high as to be prohibitive. One route to improving this is via disruption of the cells prior to lipid extraction, which can significantly increase energy recovery. Unfortunately, several obvious disruption techniques require more energy than can be gained. This dissertation examines the use of microbubbles to improve mechanical disruption of algal cells using experimental, theoretical, and computational methods. New laboratory experiments show that effective ultrasonic disruption of algae is achieved by adding microbubbles to an algal solution. The configuration studied flows the solution through a tube and insonifies a small section with a high-pressure ultrasound wave. Previous biomedical research has shown effective cell membrane damage on animal cells with similar methods, but the present research is the first to extend such study to algal cells. Results indicate that disruption increases with peak negative pressure between 1.90 and 3.07 MPa and with microbubble concentration up to 12.5 x 107 bubbles/ml. Energy estimates of this process suggest that it requires only one-fourth the currently most-efficient laboratory-scale disruption process. Estimates of the radius near each bubble that causes disruption (i.e. the disruption radius) suggest that it increases with peak negative pressure and is near 9--20 microm for all cases tested. It is anticipated that these procedures can be designed for better efficiency and efficacy, which will be facilitated by identifying the root mechanisms of the bubble-induced disruption. We therefore examine whether bubble expansion alone creates sufficient cell deformation for cell rupture. The spherically-symmetric Marmottant model for bubble dynamics allows estimation of the flow regime under experimental conditions. Bubble expansion is modeled as a point source of

  6. Heat load material studies: Simulated tokamak disruptions

    International Nuclear Information System (INIS)

    Gahl, J.M.; McDonald, J.M.; Zakharov, A.; Tserevitinov, S.; Barabash, V.; Guseva, M.

    1991-01-01

    It is clear that an improved understanding of the effects of tokamak disruptions on plasma facing component materials is needed for the ITER program. very large energy fluxes are predicted to be deposited in ITER and could be very damaging to the machine. During 1991, Sandia National Laboratories and the University of New Mexico conducted cooperative tokamak disruption simulation experiments at several Soviet facilities. These facilities were located at the Efremov Institute in Leningrad, the Kurchatov Atomic Energy Institute (Troisk and Moscow) and the Institute for Physical Chemistry of the Soviet Adademy of Sciences in Moscow. Erosion of graphite from plasma stream impact is seen to be much less than that observed with laser or electron beams with similar energy fluxes. This, along with other data obtained, seem to suggest that the ''vapor shielding'' effect is a very important phenomenon in the study of graphite erosion during tokamak disruption

  7. Maternal Characteristics Predicting Young Girls’ Disruptive Behavior

    Science.gov (United States)

    van der Molen, Elsa; Hipwell, Alison E.; Vermeiren, Robert; Loeber, Rolf

    2011-01-01

    Little is known about the relative predictive utility of maternal characteristics and parenting skills on the development of girls’ disruptive behavior. The current study used five waves of parent and child-report data from the ongoing Pittsburgh Girls Study to examine these relationships in a sample of 1,942 girls from age 7 to 12 years. Multivariate Generalized Estimating Equation (GEE) analyses indicated that European American race, mother’s prenatal nicotine use, maternal depression, maternal conduct problems prior to age 15, and low maternal warmth explained unique variance. Maladaptive parenting partly mediated the effects of maternal depression and maternal conduct problems. Both current and early maternal risk factors have an impact on young girls’ disruptive behavior, providing support for the timing and focus of the prevention of girls’ disruptive behavior. PMID:21391016

  8. Tidal Disruption Events from Eccentric Nuclear Disks

    Science.gov (United States)

    Wernke, Heather N.; Madigan, Ann-Marie

    2018-04-01

    Stars that get too close to a supermassive black hole are in danger of being tidally disrupted. Stellar two-body relaxation is commonly assumed to be the main driver of these events. Recent work has shown, however, that secular gravitational torques from eccentric nuclear disks can push stars to extreme eccentricities at much higher rates than predicted by two-body relaxation. This work did not include the effects of general relativity, however, which could quench secular torques via rapid apsidal precession. Here we show that, for a star in danger of disruption, general relativity acts on a timescale of less than an orbital period. This short timescale means that general relativity does not have enough time to have a major effect on the orbit. When driven by secular torques from eccentric nuclear disks, tidal disruption event rates are not affected by general relativity.

  9. A model for disruption generated runaway electrons

    International Nuclear Information System (INIS)

    Russo, A.J.; Campbell, R.B.

    1993-01-01

    One of the possible consequences of disruptions in tokamaks is the generation of runaway electrons which can impact plasma facing components and cause damage, owing to high local energy deposition. This problem becomes more serious as the machine size and plasma current increase. Since large size and high currents are characteristics of proposed future machines, control of runaway generation is an important design consideration. A lumped circuit model for disruption runaway electron generation indicates that impurity concentration and type, as well as plasma motion, can strongly influence runaway behaviour. A comparison of disruption data from several runs on JET and DIII-D with model results demonstrate the effects of impurities, and plasma motion, on runaway number density and energy. The model is also applied to the calculation of runaway currents for ITER. (author). 16 refs, 13 figs

  10. Energy flow during disruptions in JET

    International Nuclear Information System (INIS)

    Paley, J.I.; Andrew, P.; Cowley, S.C.; Fundamenski, W.; Huber, A.

    2005-01-01

    Disruptions place severe limitations on the materials selected for plasma facing components in fusion devices. In a disruption, the plasma stored thermal and magnetic energy is dissipated leading to predicted power loadings in the current quench of up to 10 MW m -2 in JET. In the thermal quench very high power loads of up to 10 G Wm -2 would be expected if all the power flowed to the steady state strike points, however this is not observed. In this paper the energy balance associated with both events is investigated. The magnetic energy is found to balance well with radiated energy. Circumstantial evidence for limiter interaction during the thermal quench of plasmas in divertor configuration is presented and a possible mechanism for limiter interaction in disruptions resulting from the collapse of an internal transport barrier is discussed

  11. Density turbulence and disruption phenomena in TEXTOR

    International Nuclear Information System (INIS)

    Waidmann, G.; Kuang, G.; Jadoul, M.

    1992-01-01

    Disruptive processes are observed in tokamak plasmas not only at the operating limits (density limit or q-limit) but can be found under a variety of experimental conditions. Large forces are exerted then on vessel components and support structures. The sudden release of stored plasma energy presents a serious erosion problem for the first wall already in the next generation of large tokamak machines. Strong energy losses from the plasma and an influx of impurities are already present in minor plasma disruptions which do not immediately lead to a plasma current termination. The rapid loss of energy confinement was investigated within the framework of a systematic study on plasma disruption phenomena in TEXTOR. (author) 4 refs., 4 figs

  12. Disruption effects on the beam size measurement

    International Nuclear Information System (INIS)

    Raimondi, P.; Decker, F.J.; Chen, P.

    1995-01-01

    At the SLC Final Focus with higher currents and smaller beam sizes, the disruption parameter D y is close to one and so the pinch effect should produce a luminosity enhancement. Since a flat beam-beam function is fit to deflection scan data to measure the beam size, disruption can affect the measurement. Here the authors discuss the quantitative effects of disruption for typical SLC beam parameters. With 3.5 10 10 particles per pulse, bunch length of 0.8 mm and beam sizes of 2.1 μm horizontally and 0.55 μm vertically, the measured vertical size can be as much as 25% bigger than the real one. Furthermore during the collision the spot size actually decrease, producing an enhancement factor H D of about 1.25. This would yield to a true luminosity which is 1.6 times that which is estimated from the beam-beam deflection fit

  13. Airline Disruption Management - Perspectives, Experiences and Outlook

    DEFF Research Database (Denmark)

    Kohl, Niklas; Larsen, Allan; Larsen, Jesper

    2007-01-01

    Over the past decade, airlines have become more concerned with developing an optimal flight schedule, with very little slack left to accommodate for any form of variation from the optimal solution. During operation the planned schedules often have to be revised due to disruptions caused...... part we report on experiences from a large research and development project on airline disruption management. Within the project the first prototype of a multiple resource decision support system at the operations control center in a major airline, has been implemented....... by for example severe weather, technical problems and crew sickness. Thus, the field of Airline Disruption Management has emerged within the past few years. The increased focus on cutting cost at the major airlines has intensified the interest in the development of new and cost efficient methods to handle...

  14. Airline Disruption Management - Perspectives, Experiences and Outlook

    DEFF Research Database (Denmark)

    Kohl, Niklas; Larsen, Allan; Larsen, Jesper

    2004-01-01

    Over the past decade, airlines have become more concerned with developing an optimal flight schedule, with very little slack left to accommodate for any form of variation from the optimal solution. During operation the planned schedules often have to be revised due to disruptions caused...... report on experiences from a large research and development project on airline disruption management. Within the project the first prototype of a multiple resource decision support system at the operations control center in a major airline, has been implemented....... by for example severe weather, technical problems and crew sickness. Thus, the field of Airline Disruption Management has emerged within the past few years. The increased focus on cutting cost at the major airlines has intensified the interest in the development of new and cost e cient methods to handle airline...

  15. Analytic modeling of axisymmetric disruption halo currents

    International Nuclear Information System (INIS)

    Humphreys, D.A.; Kellman, A.G.

    1999-01-01

    Currents which can flow in plasma facing components during disruptions pose a challenge to the design of next generation tokamaks. Induced toroidal eddy currents and both induced and conducted poloidal ''halo'' currents can produce design-limiting electromagnetic loads. While induction of toroidal and poloidal currents in passive structures is a well-understood phenomenon, the driving terms and scalings for poloidal currents flowing on open field lines during disruptions are less well established. A model of halo current evolution is presented in which the current is induced in the halo by decay of the plasma current and change in enclosed toroidal flux while being convected into the halo from the core by plasma motion. Fundamental physical processes and scalings are described in a simplified analytic version of the model. The peak axisymmetric halo current is found to depend on halo and core plasma characteristics during the current quench, including machine and plasma dimensions, resistivities, safety factor, and vertical stability growth rate. Two extreme regimes in poloidal halo current amplitude are identified depending on the minimum halo safety factor reached during the disruption. A 'type I' disruption is characterized by a minimum safety factor that remains relatively high (typically 2 - 3, comparable to the predisruption safety factor), and a relatively low poloidal halo current. A 'type II' disruption is characterized by a minimum safety factor comparable to unity and a relatively high poloidal halo current. Model predictions for these two regimes are found to agree well with halo current measurements from vertical displacement event disruptions in DIII-D [T. S. Taylor, K. H. Burrell, D. R. Baker, G. L. Jackson, R. J. La Haye, M. A. Mahdavi, R. Prater, T. C. Simonen, and A. D. Turnbull, open-quotes Results from the DIII-D Scientific Research Program,close quotes in Proceedings of the 17th IAEA Fusion Energy Conference, Yokohama, 1998, to be published in

  16. Disruptive event analysis: volcanism and igneous intrusion

    International Nuclear Information System (INIS)

    Crowe, B.M.

    1980-08-01

    An evaluation is made of the disruptive effects of volcanic activity with respect to long term isolation of radioactive waste through deep geologic storage. Three major questions are considered. First, what is the range of disruption effects of a radioactive waste repository by volcanic activity. Second, is it possible, by selective siting of a repository, to reduce the risk of disruption by future volcanic activity. And third, can the probability of repository disruption by volcanic activity be quantified. The main variables involved in the evaluation of the consequences of repository disruption by volcanic activity are the geometry of the magma-repository intersection (partly controlled by depth of burial) and the nature of volcanism. Potential radionuclide dispersal by volcanic transport within the biosphere ranges in distance from several kilometers to global. Risk from the most catastrophic types of eruptions can be reduced by careful site selection to maximize lag time prior to the onset of activity. Certain areas or volcanic provinces within the western United States have been sites of significant volcanism and should be avoided as potential sites for a radioactive waste repository. Examples of projection of future sites of active volcanism are discussed for three areas of the western United States. Probability calculations require two types of data: a numerical rate or frequency of volcanic activity and a numerical evaluation of the areal extent of volcanic disruption for a designated region. The former is clearly beyond the current state of art in volcanology. The latter can be approximated with a reasonable degree of satisfaction. In this report, simplified probability calculations are attempted for areas of past volcanic activity

  17. [Enzymes for disrupting bacterial communication, an alternative to antibiotics?

    Science.gov (United States)

    Rémy, B; Plener, L; Elias, M; Daudé, D; Chabrière, E

    2016-11-01

    Quorum sensing (QS) is used by bacteria to communicate and synchronize their actions according to the cell density. In this way, they produce and secrete in the surrounding environment small molecules dubbed autoinducers (AIs) that regulate the expression of certain genes. The phenotypic traits regulated by QS are diverse and include pathogenicity, biofilm formation or resistance to anti-microbial treatments. The strategy, aiming at disrupting QS, known as quorum quenching (QQ), has emerged to counteract bacterial virulence and involves QS-inhibitors (QSI) or QQ-enzymes degrading AIs. Differently from antibiotics, QQ aims at blocking cell signaling and does not alter bacterial survival. This considerably decreases the selection pressure as compared to bactericide treatments and may reduce the occurrence of resistance mechanisms. QQ-enzymes are particularly appealing as they may disrupt molecular QS-signal without entering the cell and in a catalytic way. This review covers several aspects of QQ-based medical applications and the potential subsequent emergence of resistance is discussed. Copyright © 2016 Académie Nationale de Pharmacie. All rights reserved.

  18. Energetics of LMFBR core disruptive accidents

    International Nuclear Information System (INIS)

    Marchaterre, J.F.

    1979-01-01

    In general, in the design of fast reactor systems, containment design margins are specified by investigating the response of the containment to core disruptive accidents. The results of these analyses are then translated into criteria which the designers must meet. Currently, uniform and agreed upon criteria are lacking, and in this time while they are being developed, the designer should be aware of the considerations which go into the particular criteria he must work with, and participate in their development. This paper gives an overview of the current state of the art in assessing core disruptive accidents and the design implications of this process. (orig.)

  19. Disruption problematics in segmented blanket concepts

    International Nuclear Information System (INIS)

    Crutzen, Y.; Fantechi, S.; Farfaletti-Casali, F.

    1994-01-01

    In Tokamaks, the hostile operating environment originated by plasma disruption events requires that the first wall/blanket/shield components sustain the large induced electromagnetic (EM) forces without significant structural deformation and within allowable material stresses. As a consequence there is a need to improve the safety features of the blanket design concepts satisfying the disruption problematics and to formulate guidelines on the required internal reinforcements of the blanket components. The present paper describes the recent investigations on blanket reinforcement systems needed in order to optimize the first-wall/blanket/shield structural design for next step and commercial fusion reactors in the context of ITER, DEMO and SEAFP activities

  20. Engineering aspects of disruption current decay

    International Nuclear Information System (INIS)

    Murray, J.G.

    1983-11-01

    Engineering features associated with the configuration of a tokamak can affect the amount of energy that produces melting and damage to the limiters or internal wall surfaces as the result of a major disruption. During the current decay period of a major thermal disruption, the energy that can damage a wall or limiter comes from the external magnetic field. By providing a good conducting torus near the plasma and increasing the plasma circuit resistance, this magnetic energy (transferred by way of the plasma circuit) can be minimized. This report addresses engineering design features to reduce the energy deposited on the inner torus surface that produces melting of the structures

  1. Manufacturing doubt about endocrine disrupter science

    DEFF Research Database (Denmark)

    Bergman, Åke; Becher, Georg; Blumberg, Bruce

    2015-01-01

    We present a detailed response to the critique of "State of the Science of Endocrine Disrupting Chemicals 2012" (UNEP/WHO, 2013) by financial stakeholders, authored by Lamb et al. (2014). Lamb et al.'s claim that UNEP/WHO (2013) does not provide a balanced perspective on endocrine disruption......) report is not particularly erudite and that their critique is not intended to be convincing to the scientific community, but to confuse the scientific data. Consequently, it promotes misinterpretation of the UNEP/WHO (2013) report by non-specialists, bureaucrats, politicians and other decision makers...

  2. Development of disruption thermal analysis code DREAM

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Seiichiro; Kobayahsi, Takeshi [Kawasaki Heavy Industries Ltd., Kobe (Japan); Seki, Masahiro

    1989-07-01

    When a plasma disruption takes place in a tokamak type fusion reactor, plasma facing componenets such as first wall and divertor/limiter are subjected to a intensse heat load in a short duration. At the surface of the wall, temperature rapidly rises, and melting and evaporation occurs. It causes reduction of wall thickness and crack initiation/propagation. As lifetime of the components is significantly affected by them, the transient analysis in consideration of phase changes and radiation heat loss in required in the design of these components. This paper describes the computer code DREAM, developed to perform the disruption thermal analysis, taking phase changes and radiation into account. (author).

  3. Development of disruption thermal analysis code DREAM

    International Nuclear Information System (INIS)

    Yamazaki, Seiichiro; Kobayahsi, Takeshi; Seki, Masahiro.

    1989-01-01

    When a plasma disruption takes place in a tokamak type fusion reactor, plasma facing componenets such as first wall and divertor/limiter are subjected to a intensse heat load in a short duration. At the surface of the wall, temperature rapidly rises, and melting and evaporation occurs. It causes reduction of wall thickness and crack initiation/propagation. As lifetime of the components is significantly affected by them, the transient analysis in consideration of phase changes and radiation heat loss in required in the design of these components. This paper describes the computer code DREAM, developed to perform the disruption thermal analysis, taking phase changes and radiation into account. (author)

  4. Endocrine Disrupters: the new players able to affect the epigenome.

    Directory of Open Access Journals (Sweden)

    Lavinia eCasati

    2015-06-01

    Full Text Available Epigenetics represents the way by which the environment is able to program the genome; there are three main levels of epigenetic control on genome: DNA methylation, post-translational histone modification and microRNA expression. The term Epigenetics has been widened by NIH to include both heritable changes in gene activity and expression but also stable, long-term alterations in the transcriptional potential of a cell that are not necessarily heritable. These changes might be produced mostly by the early life environment and might affect health influencing the susceptibility to develop diseases, from cancer to mental disorder, during the entire life span. The most studied environmental influences acting on epigenome are diet, infections, wasting, child care, smoking and environmental pollutants, in particular endocrine disrupters (EDs. These are environmental xenobiotics able to interfere with the normal development of the male and female reproductive systems of wildlife, of experimental animals and possibly of humans, disrupting the normal reproductive functions. Data from literature indicate that EDs can act at different levels of epigenetic control, in some cases transgenerationally, in particular when the exposure to these compounds occurs during the prenatal and earliest period of life. Some of the best characterized EDs will be considered in this review. Among the EDs, vinclozolin (VZ and methoxychlor (MXC promote epigenetic transgenerational effects. Polychlorinated biphenils (PCBs, the most widespread environmental EDs, affect histone post-translational modifications in a dimorphic way, possibly as the result of an alteration of gene expression of the enzymes involved in histone modification, as the demethylase Jarid1b, an enzyme also involved in regulating the interaction of androgens with their receptor.

  5. Pesticides Provoke Endocrine Disruption A Review

    International Nuclear Information System (INIS)

    Aly, M.A.S.

    2006-01-01

    Increasing numbers of environmental chemicals,including pesticides, have the ability to produce endocrine disruption by various mechanisms. such substances may affect hormone secretion from an endocrine gland and may alter the rate of hormone elimination from the body. environmental chemicals may also disrupt regulatory feedback mechanisms that exist between two endocrine organs; or may interact with a hormone receptor either by mimicking or antagonizing the actions of the natural hormone. these chemicals are referred to endocrine disruptive chemicals (EDC's). EDC's act to alter the blood hormone levels or the subsequent action of hormones . the use of radioimmunoassay(RIA) constitutes a superior and unrivalled tool for the determination and quantification of hormones.the endocrine system participates in virtually all important functions of an organism, such as sexual differentiation before birth, sexual maturation during puberty, reproduction in adulthood, growth, metabolism, digestion, cardiovascular function and excretion. hormones are also implicated in the etiology of certain cancers of hormone- dependent tissues, such as those of the breast, uterus, and prostate gland. therefore, endocrine disruption can potentially produce widespread effects. scientists should not stick to the past belief which presumes that pesticides have limited effect on some hormones. A paradigm shift in which a wider vision of understanding of the wholesome complex effects of pesticides on the whole body rather than a narrow limited understanding should take place

  6. Time scales in tidal disruption events

    Directory of Open Access Journals (Sweden)

    Krolik J.

    2012-12-01

    Full Text Available We explore the temporal structure of tidal disruption events pointing out the corresponding transitions in the lightcurves of the thermal accretion disk and of the jet emerging from such events. The hydrodynamic time scale of the disrupted star is the minimal time scale of building up the accretion disk and the jet and it sets a limit on the rise time. This suggest that Swift J1644+57, that shows several flares with a rise time as short as a few hundred seconds could not have arisen from a tidal disruption of a main sequence star whose hydrodynamic time is a few hours. The disrupted object must have been a white dwarf. A second important time scale is the Eddington time in which the accretion rate changes form super to sub Eddington. It is possible that such a transition was observed in the light curve of Swift J2058+05. If correct this provides interesting constraints on the parameters of the system.

  7. Thyroid effects of endocrine disrupting chemicals.

    Science.gov (United States)

    Boas, Malene; Feldt-Rasmussen, Ulla; Main, Katharina M

    2012-05-22

    In recent years, many studies of thyroid-disrupting effects of environmental chemicals have been published. Of special concern is the exposure of pregnant women and infants, as thyroid disruption of the developing organism may have deleterious effects on neurological outcome. Chemicals may exert thyroid effects through a variety of mechanisms of action, and some animal experiments and in vitro studies have focused on elucidating the mode of action of specific chemical compounds. Long-term human studies on effects of environmental chemicals on thyroid related outcomes such as growth and development are still lacking. The human exposure scenario with life long exposure to a vast mixture of chemicals in low doses and the large physiological variation in thyroid hormone levels between individuals render human studies very difficult. However, there is now reasonably firm evidence that PCBs have thyroid-disrupting effects, and there is emerging evidence that also phthalates, bisphenol A, brominated flame retardants and perfluorinated chemicals may have thyroid disrupting properties. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  8. Analysis of recent fuel-disruption experiments

    International Nuclear Information System (INIS)

    Kramer, J.M.; Kraft, T.E.; DiMelfi, R.J.; Fenske, G.R.; Gruber, E.E.

    1982-01-01

    Recent USDOE-sponsored DEH, FGR, and TREAT F series fuel-disruption experiments are analyzed with existing analytical models. The experiments are interpreted and the results used to evaluate the models. Calculations are presented using the FRAS3 fission-gas-behavior code and the DiMelfi-Deitrich fuel-response model

  9. Operational limits and disruptions in ITER

    Energy Technology Data Exchange (ETDEWEB)

    Tsunematsu, T; Mizoguchi, T; Yoshino, R [Japan Atomic Energy Research Inst., Tokyo (Japan); Borrass, K; Engelmann, F; Pacher, G; Pacher, H [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany, F.R.). NET Design Team; Cohen, S; Post, D [Princeton Univ., NJ (USA). Plasma Physics Lab.; Hogan, J; Uckan, N A [Oak Ridge National Lab., TN (USA); Krasheninnikov, S; Mukhovatov, V; Parail, V

    1990-12-15

    Detailed knowledge of the operational limits for beta, q and the plasma density will be required for successful and flexible operation of ITER. In this paper, the present data base and guidelines on operational limits and disruptions in the ITER design are presented. 10 refs., 1 fig.

  10. Maternal Characteristics Predicting Young Girls' Disruptive Behavior

    Science.gov (United States)

    van der Molen, Elsa; Hipwell, Alison E.; Vermeiren, Robert; Loeber, Rolf

    2011-01-01

    Little is known about the relative predictive utility of maternal characteristics and parenting skills on the development of girls' disruptive behavior. The current study used five waves of parent- and child-report data from the ongoing Pittsburgh Girls Study to examine these relationships in a sample of 1,942 girls from age 7 to 12 years.…

  11. Management of posterior urethral disruption injuries.

    Science.gov (United States)

    Myers, Jeremy B; McAninch, Jack W

    2009-03-01

    Posterior urethral disruption is a traumatic injury to the male urethra, which most often results from pelvic fracture. After trauma, the distraction defect between the two ends of the urethra often scars and becomes fibrotic, blocking the urethra and bladder emptying. Increasing evidence suggests that many posterior urethral disruptions occur at the junction between the membranous urethra and the bulbar urethra, which is distal to the rhabdosphincter. In the acute setting, when a posterior urethral disruption is suspected, retrograde urethrography should be performed. Posterior urethral disruptions can be managed acutely by realignment of the urethra over a urethral catheter or by placement of a suprapubic catheter for bladder drainage only. Once fibrosis has stabilized, the patient can undergo posterior urethroplasty. In most cases, this procedure can be performed via a perineal approach in a single-stage surgery. The results of this single-stage perineal urethroplasty are excellent, and a patent urethra can be re-established in the majority of men who undergo surgery.

  12. Development of Disruptive Open Access Journals

    Science.gov (United States)

    Anderson, Terry; McConkey, Brigette

    2009-01-01

    Open access (OA) publication has emerged, with disruptive effects, as a major outlet for scholarly publication. OA publication is usually associated with on-line distribution and provides access to scholarly publications to anyone, anywhere--regardless of their ability to pay subscription fees or their association with an educational institution.…

  13. Disrupting Educational Inequalities through Youth Digital Activism

    Science.gov (United States)

    Stornaiuolo, Amy; Thomas, Ebony Elizabeth

    2017-01-01

    This article reviews scholarship on youth and young adult activism in digital spaces, as young users of participatory media sites are engaging in political, civic, social, or cultural action and advocacy online to create social change. The authors argue that youth's digital activism serves as a central mechanism to disrupt inequality, and that…

  14. An analysis of recent fuel disruption experiments

    International Nuclear Information System (INIS)

    Kramer, J.M.; Kraft, T.E.; Dimelfi, R.J.; Fenske, G.R.; Gruber, E.E.

    1982-01-01

    Recent USDOE-Sponsored DEH, FGR, and TREAT F series fuel disruption experiments are analyzed with existing analytical models. The experiments are interpreted and the results used to evaluate the models. Calculations are presented using the FRAS3 fission gas behavior code and the DiMelfi-Deitrich fuel response model

  15. Endocrine Disrupting Chemicals and Disease Susceptibility

    Science.gov (United States)

    Schug, Thaddeus T.; Janesick, Amanda; Blumberg, Bruce; Heindel, Jerrold J.

    2011-01-01

    Environmental chemicals have significant impacts on biological systems. Chemical exposures during early stages of development can disrupt normal patterns of development and thus dramatically alter disease susceptibility later in life. Endocrine disrupting chemicals (EDCs) interfere with the body's endocrine system and produce adverse developmental, reproductive, neurological, cardiovascular, metabolic and immune effects in humans. A wide range of substances, both natural and man-made, are thought to cause endocrine disruption, including pharmaceuticals, dioxin and dioxin-like compounds, polychlorinated biphenyls, DDT and other pesticides, and components of plastics such as bisphenol A (BPA) and phthalates. EDCs are found in many everyday products– including plastic bottles, metal food cans, detergents, flame retardants, food additives, toys, cosmetics, and pesticides. EDCs interfere with the synthesis, secretion, transport, activity, or elimination of natural hormones. This interference can block or mimic hormone action, causing a wide range of effects. This review focuses on the mechanisms and modes of action by which EDCs alter hormone signaling. It also includes brief overviews of select disease endpoints associated with endocrine disruption. PMID:21899826

  16. Natural and Professional Help during Marital Disruption.

    Science.gov (United States)

    Toro, Paul A.; Zax, Melvin

    Although few people bring their psychological problems to mental health professionals, research in the area of 'natural' help is rudimentary. To investigate the process and effectiveness of natural professional groups in helping individuals experiencing marital disruption, 42 helpers (14 mental health professionals, 14 divorce lawyers, and 14…

  17. Five disruptive technology directions for 5G

    DEFF Research Database (Denmark)

    Boccardi, Federico; W. Heath Jr., Robert; Lozano, Angel

    2014-01-01

    New research directions will lead to fundamental changes in the design of future fifth generation (5G) cellular networks. This article describes five technologies that could lead to both architectural and component disruptive design changes: device-centric architectures, millimeter wave, massive ...

  18. Disrupted functional connectivity in adolescent obesity

    Directory of Open Access Journals (Sweden)

    Laura Moreno-Lopez

    2016-01-01

    Conclusions: These findings suggest that adolescent obesity is linked to disrupted functional connectivity in brain networks relevant to maintaining balance between reward, emotional memories and cognitive control. Our findings may contribute to reconceptualization of obesity as a multi-layered brain disorder leading to compromised motivation and control, and provide a biological account to target prevention strategies for adolescent obesity.

  19. Traffic disruption route Einstein near building 170

    CERN Multimedia

    A Lopez - TS/CE

    2005-01-01

    The TS/CE Group informs you that, for the duration of the work at Building 170, there may be some disruption to traffic on route Einstein in the vicinity of Building 170. The work is due to take place from the 14th to 18th February. For more information, please contact 165029. A. Lopez TS/CE

  20. New directions for mating disruption in Wisconsin

    Science.gov (United States)

    Mating Disruption (MD) is an alternative to insecticide for control of three major pests -Sparganthois fruitworm, Cranberry fruitworm and Blackheaded fireworm. MD functions by sending out false plumes of the insect's sex pheromones – this interferes with the insect’s ability to find a mate, preempti...

  1. The Relative Ineffectiveness of Criminal Network Disruption

    Science.gov (United States)

    Duijn, Paul A. C.; Kashirin, Victor; Sloot, Peter M. A.

    2014-01-01

    Researchers, policymakers and law enforcement agencies across the globe struggle to find effective strategies to control criminal networks. The effectiveness of disruption strategies is known to depend on both network topology and network resilience. However, as these criminal networks operate in secrecy, data-driven knowledge concerning the effectiveness of different criminal network disruption strategies is very limited. By combining computational modeling and social network analysis with unique criminal network intelligence data from the Dutch Police, we discovered, in contrast to common belief, that criminal networks might even become ‘stronger’, after targeted attacks. On the other hand increased efficiency within criminal networks decreases its internal security, thus offering opportunities for law enforcement agencies to target these networks more deliberately. Our results emphasize the importance of criminal network interventions at an early stage, before the network gets a chance to (re-)organize to maximum resilience. In the end disruption strategies force criminal networks to become more exposed, which causes successful network disruption to become a long-term effort. PMID:24577374

  2. Anomalous periodic disruptions in tokamak plasma

    International Nuclear Information System (INIS)

    Montvai, A.; Tegze, M.; Valyi, I.

    1982-09-01

    Anomalously strong, periodic instabilities were observed in the MT-1 tokamak. Characteristics of these instabilities were partly similar to those of internal disruptions, but there were features making them different from the normal relaxational oscillations. Basic characteristics of the phenomenon were studied with the aid of generally used diagnostics. (author)

  3. Biosensor discovery of thyroxine transport disrupting chemicals

    NARCIS (Netherlands)

    Marchesini, G.R.; Meimaridou, A.; Haasnoot, W.; Meulenberg, E.; Albertus, F.; Mizuguchi, M.; Takeuchi, M.; Irth, H.; Murk, A.J.

    2008-01-01

    Ubiquitous chemicals may interfere with the thyroid system that is essential in the development and physiology of vertebrates. We applied a surface plasmon resonance (SPR) biosensor-based screening method for the fast screening of chemicals with thyroxine (T4) transport disrupting activity. Two

  4. Disruptive instabilities in the TBR-1

    International Nuclear Information System (INIS)

    Vannucci, A.

    1987-01-01

    The disruptive instabilities in the TBR-1 tokamak of the Plasma Physics Laboratory of the Institute of Physics-USP were investigated by using surface-barrier detectors and Mirnov magnetic coils, measuring soft X-ray emited by the plasma and poloidal magnetic fluctuations, respectively. Minor and major disruptions, as well sawteeth oscillations, were identified at the TBR-1 discharges, and their main characteristics were studied. Comparing the measured period of the internal disruptions (sawteeth) with the ones expected from scaling laws, good agreements is reached. The measured sawteeth crashes agree with the values expected from the Kadomtsev's model. External helical fields (CHR), corresponding to m/n=2/1 helicity were produced in order to inhibit or criate disruptive instabilities. A strong weakening of the mhd activity, present in the TBR-1 discharges, was clearly detected. The soft X-ray detection system, projected and constructed for this work, was used to obtain the electron temperatures of regions close to the center of the plasma column (T(r=0) ∼ 205 eV and T(r ± 3,8) ∼ 85 eV), using the absorbing foils method. Using the Spitzer formula, Z sub (eff) values were also obtained. (author) [pt

  5. The Structure of Childhood Disruptive Behaviors

    Science.gov (United States)

    Martel, Michelle M.; Gremillion, Monica; Roberts, Bethan; von Eye, Alexander; Nigg, Joel T.

    2010-01-01

    Attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) frequently co-occur. Comorbidity of these 2 childhood disruptive behavior domains has not been satisfactorily explained at either a structural or etiological level. The current study evaluated a bifactor model, which allows for a "g" factor in addition to…

  6. Promotion of malignant phenotype after disruption of the three-dimensional structure of cultured spheroids from colorectal cancer.

    Science.gov (United States)

    Piulats, Jose M; Kondo, Jumpei; Endo, Hiroko; Ono, Hiromasa; Hagihara, Takeshi; Okuyama, Hiroaki; Nishizawa, Yasuko; Tomita, Yasuhiko; Ohue, Masayuki; Okita, Kouki; Oyama, Hidejiro; Bono, Hidemasa; Masuko, Takashi; Inoue, Masahiro

    2018-03-23

    Individual and small clusters of cancer cells may detach from the edges of a main tumor and invade vessels, which can act as the origin of metastasis; however, the mechanism for this phenomenon is not well understood. Using cancer tissue-originated spheroids, we studied whether disturbing the 3D architecture of cancer spheroids can provoke the reformation process and progression of malignancy. We developed a mechanical disruption method to achieve homogenous disruption of the spheroids while maintaining cell-cell contact. After the disruption, 9 spheroid lines from 9 patient samples reformed within a few hours, and 3 of the 9 lines exhibited accelerated spheroid growth. Marker expression, spheroid forming capacity, and tumorigenesis indicated that stemness increased after spheroid disruption. In addition, the spheroid forming capacity increased in 6 of 11 spheroid lines. The disruption signature determined by gene expression profiling supported the incidence of remodeling and predicted the prognosis of patients with colorectal cancer. Furthermore, WNT and HER3 signaling were increased in the reformed spheroids, and suppression of these signaling pathways attenuated the increased proliferation and stemness after the disruption. Overall, the disruption and subsequent reformation of cancer spheroids promoted malignancy-related phenotypes through the activation of the WNT and ERBB pathways.

  7. The mass disruption of Jupiter Family comets

    Science.gov (United States)

    Belton, Michael J. S.

    2015-01-01

    I show that the size-distribution of small scattered-disk trans-neptunian objects when derived from the observed size-distribution of Jupiter Family comets (JFCs) and other observational constraints implies that a large percentage (94-97%) of newly arrived active comets within a range of 0.2-15.4 km effective radius must physically disrupt, i.e., macroscopically disintegrate, within their median dynamical lifetime. Additional observational constraints include the numbers of dormant and active nuclei in the near-Earth object (NEO) population and the slope of their size distributions. I show that the cumulative power-law slope (-2.86 to -3.15) of the scattered-disk TNO hot population between 0.2 and 15.4 km effective radius is only weakly dependent on the size-dependence of the otherwise unknown disruption mechanism. Evidently, as JFC nuclei from the scattered disk evolve into the inner Solar System only a fraction achieve dormancy while the vast majority of small nuclei (e.g., primarily those with effective radius <2 km) break-up. The percentage disruption rate appears to be comparable with that of the dynamically distinct Oort cloud and Halley type comets (Levison, H.F., Morbidelli, A., Dones, L., Jedicke, R., Wiegert, P.A., Bottke Jr., W.F. [2002]. Science 296, 2212-2215) suggesting that all types of comet nuclei may have similar structural characteristics even though they may have different source regions and thermal histories. The typical disruption rate for a 1 km radius active nucleus is ∼5 × 10-5 disruptions/year and the dormancy rate is typically 3 times less. We also estimate that average fragmentation rates range from 0.01 to 0.04 events/year/comet, somewhat above the lower limit of 0.01 events/year/comet observed by Chen and Jewitt (Chen, J., Jewitt, D.C. [1994]. Icarus 108, 265-271).

  8. Perceptual consequences of disrupted auditory nerve activity.

    Science.gov (United States)

    Zeng, Fan-Gang; Kong, Ying-Yee; Michalewski, Henry J; Starr, Arnold

    2005-06-01

    Perceptual consequences of disrupted auditory nerve activity were systematically studied in 21 subjects who had been clinically diagnosed with auditory neuropathy (AN), a recently defined disorder characterized by normal outer hair cell function but disrupted auditory nerve function. Neurological and electrophysical evidence suggests that disrupted auditory nerve activity is due to desynchronized or reduced neural activity or both. Psychophysical measures showed that the disrupted neural activity has minimal effects on intensity-related perception, such as loudness discrimination, pitch discrimination at high frequencies, and sound localization using interaural level differences. In contrast, the disrupted neural activity significantly impairs timing related perception, such as pitch discrimination at low frequencies, temporal integration, gap detection, temporal modulation detection, backward and forward masking, signal detection in noise, binaural beats, and sound localization using interaural time differences. These perceptual consequences are the opposite of what is typically observed in cochlear-impaired subjects who have impaired intensity perception but relatively normal temporal processing after taking their impaired intensity perception into account. These differences in perceptual consequences between auditory neuropathy and cochlear damage suggest the use of different neural codes in auditory perception: a suboptimal spike count code for intensity processing, a synchronized spike code for temporal processing, and a duplex code for frequency processing. We also proposed two underlying physiological models based on desynchronized and reduced discharge in the auditory nerve to successfully account for the observed neurological and behavioral data. These methods and measures cannot differentiate between these two AN models, but future studies using electric stimulation of the auditory nerve via a cochlear implant might. These results not only show the unique

  9. Phenomenology of high density disruptions in the TFTR tokamak

    International Nuclear Information System (INIS)

    Fredrickson, E.D.; McGuire, K.M.; Bell, M.G.

    1993-01-01

    Studies of high density disruptions on TFTR, including a comparison of minor and major disruptions at high density, provide important new information regarding the nature of the disruption mechanism. Further, for the first time, an (m,n)=(1,1) 'cold bubble' precursor to high density disruptions has been experimentally observed in the electron temperature profile. The precursor to major disruptions resembles the 'vacuum bubble' model of disruptions first proposed by B.B. Kadomtsev and O.P. Pogutse (Sov. Phys. - JETP 38 (1974) 283). (author). Letter-to-the-editor. 25 refs, 3 figs

  10. 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.

  11. Alleviation of glucose repression of maltose metabolism by MIG1 disruption in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Klein, Christopher; Olsson, Lisbeth; Rønnow, B.

    1996-01-01

    The MIG1 gene was disrupted in a haploid laboratory strain (B224) and in an industrial polyploid strain (DGI 342) of Saccharomyces cerevisiae. The alleviation of glucose repression of the expression of MAL genes and alleviation of glucose control of maltose metabolism were investigated in batch...... cultivations on glucose-maltose mixtures. In the MIG1-disrupted haploid strain, glucose repression was partly alleviated; i.e., maltose metabolism was initiated at higher glucose concentrations than in the corresponding wild-type strain. In contrast, the polyploid Delta mig1 strain exhibited an even more...... stringent glucose control of maltose metabolism than the corresponding wild-type strain, which could be explained by a more rigid catabolite inactivation of maltose permease, affecting the uptake of maltose. Growth on the glucose-sucrose mixture showed that the polyploid Delta mig1 strain was relieved...

  12. Disrupt mig vel: Fire gode råd om disruption

    DEFF Research Database (Denmark)

    Rydén, Pernille; Ringberg, Torsten; Østergaard Jacobsen, Per

    2017-01-01

    Forandring. Ønsket om at være teknologisk foran, kommer ofte til at ske på bekostning af fokus på kundernes oplevelser. Lighedstegnet mellem disruption og ny teknologi er kun den halve sandhed.......Forandring. Ønsket om at være teknologisk foran, kommer ofte til at ske på bekostning af fokus på kundernes oplevelser. Lighedstegnet mellem disruption og ny teknologi er kun den halve sandhed....

  13. Specialized Information Processing Deficits and Distinct Metabolomic Profiles Following TM-Domain Disruption of Nrg1

    OpenAIRE

    O'Tuathaigh, Colm MP; Mathur, Naina; O'Callaghan, Matthew J; MacIntyre, Lynsey; Harvey, Richard; Lai, Dona; Waddington, John L; Pickard, Bemjamom S; Watson, David D; Moran, Paula M

    2017-01-01

    While there is considerable genetic and pathologic evidence for an association between neuregulin 1 (NRG1) dysregulation and schizophrenia, the underlying molecular and cellular mechanisms remain unclear. Mutant mice containing disruption of the transmembrane (TM) domain of the NRG1 gene constitute a heuristic model for dysregulation of NRG1-ErbB4 signalling in schizophrenia. The present study focused on specialised behavioural and characterisation of hitherto un-characterised information pro...

  14. Disruption of Lysosome Function Promotes Tumor Growth and Metastasis in Drosophila *

    OpenAIRE

    Chi, Congwu; Zhu, Huanhu; Han, Min; Zhuang, Yuan; Wu, Xiaohui; Xu, Tian

    2010-01-01

    Lysosome function is essential to many physiological processes. It has been suggested that deregulation of lysosome function could contribute to cancer. Through a genetic screen in Drosophila, we have discovered that mutations disrupting lysosomal degradation pathway components contribute to tumor development and progression. Loss-of-function mutations in the Class C vacuolar protein sorting (VPS) gene, deep orange (dor), dramatically promote tumor overgrowth and invasion of the RasV12 cells....

  15. Longitudinal association between marital disruption and child BMI and obesity.

    Science.gov (United States)

    Arkes, Jeremy

    2012-08-01

    This research examines whether family disruptions (i.e., divorces and separation) contribute to children's weight problems. The sample consists of 7,299 observations for 2,333 children, aged 5-14, over the 1986-2006 period, from a US representative sample from the Child and Young Adult Survey accompanying the National Longitudinal Survey of Youth (NLSY). The study uses individual-fixed-effects models in a longitudinal framework to compare children's BMI and weight problems before and after a disruption. Furthermore, besides doing a before-after comparison for children, the study also estimates the effects at various periods relative to the disruption in order to examine whether children are affected before the disruption and whether any effects change as time passes from the disruption, as some effects may be temporary or slow to develop. Despite having a larger sample than the previous studies, the results provide no evidence that, on average, children's BMI and BMI percentile scores (measured with continuous outcomes) are affected before the disruption, after the disruption, and as time passes from the disruption, relative to a baseline period a few years before the disruption. However, children experiencing a family disruption do have an increased risk of obesity (having a BMI percentile score of 95 or higher) in the two years leading up to the disruption as well as after the disruption, and as time passes from the disruption.

  16. Thyroid endocrine disruption in zebrafish larvae after exposure to mono-(2-ethylhexyl phthalate (MEHP.

    Directory of Open Access Journals (Sweden)

    Wenhui Zhai

    Full Text Available Phthalates are extensively used as plasticizers in a variety of daily-life products, resulting in widespread distribution in aquatic environments. However, limited information is available on the endocrine disrupting effects of phthalates in aquatic organisms. The aim of the present study was to examine whether exposure to mono-(2-ethylhexyl phthalate (MEHP, the hydrolytic metabolite of di-(2-ethylhexyl phthalate (DEHP disrupts thyroid endocrine system in fish. In this study, zebrafish (Danio rerio embryos were exposed to different concentrations of MEHP (1.6, 8, 40, and 200 μg/L from 2 h post-fertilization (hpf to 168 hpf. The whole-body content of thyroid hormone and transcription of genes involved in the hypothalamic-pituitary-thyroid (HPT axis were examined. Treatment with MEHP significantly decreased whole-body T4 contents and increased whole-body T3 contents, indicating thyroid endocrine disruption. The upregulation of genes related to thyroid hormone metabolism (Dio2 and UGT1ab might be responsible for decreased T4 contents. Elevated gene transcription of Dio1 was also observed in this study, which might assist to degrade increased T3 contents. Exposure to MEHP also significantly induced transcription of genes involved in thyroid development (Nkx2.1 and Pax8 and thyroid hormone synthesis (TSHβ, NIS and TG. However, the genes encoding proteins involved in TH transport (transthyretin, TTR was transcriptionally significantly down-regulated after exposure to MEHP. Overall, these results demonstrate that acute exposure to MEHP alters whole-body contents of thyroid hormones in zebrafish embryos/larvae and changes the transcription of genes involved in the HPT axis, thus exerting thyroid endocrine toxicity.

  17. Make disruptive technological change happen - The case of additive manufacturing

    DEFF Research Database (Denmark)

    Maresch, Daniela; Gartner, Johannes

    2018-01-01

    Disruptive technological change can contribute to a more abundant world. However, potentially disruptive technologies often struggle to significantly influence practice. One prominent example is additive manufacturing (AM). Although AM is often regarded as the next great technological revolution...

  18. Disruptive behaviour in the Foundation Phase of schooling | Marais ...

    African Journals Online (AJOL)

    Data collection was done by conducting interviews comprising semistructured questions with Foundation Phase teachers. Strategies purposely devised to deal specifically with the identified types and causes of disruptive behaviour are explained. Keywords: disciplinary procedures; discipline problems; disruptive behaviour;

  19. CUMULATIVE DEVELOPMENTAL EFFECTS OF ENDOCRINE DISRUPTERS: SYNERGY OR ADDITIVITY?

    Science.gov (United States)

    Exposure to chemicals with hormonal activity during critical developmental periods can disrupt reproductive function and development. Within the last decade, several classes of pesticides and toxic substances have been shown to disrupt differentiation of the male rat reproductive...

  20. Science and policy on endocrine disrupters must not be mixed

    DEFF Research Database (Denmark)

    Bergman, Åke; Andersson, Anna-Maria; Becher, Georg

    2013-01-01

    The "common sense" intervention by toxicology journal editors regarding proposed European Union endocrine disrupter regulations ignores scientific evidence and well-established principles of chemical risk assessment. In this commentary, endocrine disrupter experts express their concerns about a r...

  1. Neural net prediction of tokamak plasma disruptions

    International Nuclear Information System (INIS)

    Hernandez, J.V.; Lin, Z.; Horton, W.; McCool, S.C.

    1994-10-01

    The computation based on neural net algorithms in predicting minor and major disruptions in TEXT tokamak discharges has been performed. Future values of the fluctuating magnetic signal are predicted based on L past values of the magnetic fluctuation signal, measured by a single Mirnov coil. The time step used (= 0.04ms) corresponds to the experimental data sampling rate. Two kinds of approaches are adopted for the task, the contiguous future prediction and the multi-timescale prediction. Results are shown for comparison. Both networks are trained through the back-propagation algorithm with inertial terms. The degree of this success indicates that the magnetic fluctuations associated with tokamak disruptions may be characterized by a relatively low-dimensional dynamical system

  2. The hexagon hypothesis: Six disruptive scenarios.

    Science.gov (United States)

    Burtles, Jim

    2015-01-01

    This paper aims to bring a simple but effective and comprehensive approach to the development, delivery and monitoring of business continuity solutions. To ensure that the arguments and principles apply across the board, the paper sticks to basic underlying concepts rather than sophisticated interpretations. First, the paper explores what exactly people are defending themselves against. Secondly, the paper looks at how defences should be set up. Disruptive events tend to unfold in phases, each of which invites a particular style of protection, ranging from risk management through to business continuity to insurance cover. Their impact upon any business operation will fall into one of six basic scenarios. The hexagon hypothesis suggests that everyone should be prepared to deal with each of these six disruptive scenarios and it provides them with a useful benchmark for business continuity.

  3. Disruption of the Arabidopsis CGI-58 homologue produces Chanarin–Dorfman-like lipid droplet accumulation in plants

    OpenAIRE

    James, Christopher N.; Horn, Patrick J.; Case, Charlene R.; Gidda, Satinder K.; Zhang, Daiyuan; Mullen, Robert T.; Dyer, John M.; Anderson, Richard G. W.; Chapman, Kent D.

    2010-01-01

    CGI-58 is the defective gene in the human neutral lipid storage disease called Chanarin-Dorfman syndrome. This disorder causes intracellular lipid droplets to accumulate in nonadipose tissues, such as skin and blood cells. Here, disruption of the homologous CGI-58 gene in Arabidopsis thaliana resulted in the accumulation of neutral lipid droplets in mature leaves. Mass spectroscopy of isolated lipid droplets from cgi-58 loss-of-function mutants showed they contain triacylglycerols with common...

  4. Disruption studies in DIII-D

    International Nuclear Information System (INIS)

    Kellman, A.G.; Evans, T.E.; Cuthbertson, J.W.

    1996-09-01

    Characteristics of disruptions in the DIII-D tokamak including the current decay rate, halo current magnitude and toroidal asymmetry, and heat pulse to the divertor are described. Neon and argon pellet injection is shown to be an effective method for mitigating the halo currents and the heat pulse with a 50% reduction in both quantities achieved. The injection of these impurity pellets frequently gives rise to runaway electrons

  5. Disruption Studies in JT-60U

    International Nuclear Information System (INIS)

    Kawano, Y.; Yoshino, R.; Neyatani, Y.; Nakamura, Y.; Tokuda, S.; Tamai, H.

    2002-01-01

    Intensive studies on the physics of disruptions and developments of avoidance/mitigation methods of disruption-related phenomena have being carried out in JT-60U. The characteristics of the disruption sequence were well understood from the observation of the relationship between the heat pulse onto divertor plates during thermal quench and the impurity influx into the plasma, which determined the speed of the following current quench. A fast shutdown was first demonstrated by injecting impurity ice pellets to the plasma and intensively reducing the heat flux on first wall. The halo current and its toroidal asymmetry were precisely measured, and the halo current database was made for ITER in a wide parameter range. It was found that TPF x I h /I p0 was 0.52 at the maximum in a large tokamak like the JT-60U, whereas the higher factor of 0.75 had been observed in medium-sized tokamaks such as Alcator C-Mod and ASDEX-Upgrade. The vertical displacement event (VDE) at the start of the current quench was carefully investigated, and the neutral point where the VDE hardly occurs was discovered. MHD simulations clarified the onset mechanisms of the VDE, in which the eddy current effect of the up-down asymmetric resistive shell was essential. The real-time Z j measurement was improved for avoiding VDEs during slow current quench, and plasma-wall interaction was avoided by a well-optimized plasma equilibrium control. Magnetic fluctuations that were spontaneously generated at the disruption and/or enhanced by the externally applied helical field have been shown to avoid the generation of runaway electrons. Numerical analysis clarified an adequate rate of collisionless loss of runaway electrons in turbulent magnetic fields, which was consistent with the avoidance of runaway electron generation by magnetic fluctuations observed in JT-60U. Once generated, runaway electrons were suppressed when the safety factor at the plasma surface was reduced to 3 or 2

  6. Internal disruptions in Tokamak: a turbulent interpretation

    International Nuclear Information System (INIS)

    Dubois, M.A.; Pecquet, A.L.; Reverdin, C.

    1982-07-01

    High speed X-ray data of sawteeth in TFR are interpreted using a kinematic model. It is shown that the internal disruption begins for a small size of the q = 1 island, and that the sharp details observed on different chords are not reproduced by a total reconnection model. Conversely they are well simulated by a model where the temperature flattening is due to the propagation of a turbulent region starting from the q = 1 surface

  7. Disrupting Mating Behavior of Diaphorina citri (Liviidae).

    Science.gov (United States)

    Lujo, S; Hartman, E; Norton, K; Pregmon, E A; Rohde, B B; Mankin, R W

    2016-12-01

    Severe economic damage from citrus greening disease, caused by 'Candidatus Liberibacter asiaticus' bacteria, has stimulated development of methods to reduce mating and reproduction in populations of its insect vector, Diaphorina citri (Hemiptera: Liviidae). Male D. citri find mating partners by walking on host plants, intermittently producing vibrational calls that stimulate duetting replies by receptive females. The replies provide orientational feedback, assisting the search process. To test a hypothesis that D. citri mating can be disrupted using vibrational signals that compete with and/or mask female replies, courtship bioassays were conducted in citrus trees with or without interference from female reply mimics produced by a vibrating buzzer. Statistically significant reductions occurred in the rates and proportions of mating when the buzzer produced reply mimics within 0.4 s after male courtship calls compared with undisturbed controls. Observations of courtship behaviors in the two bioassays revealed activity patterns that likely contributed to the reductions. In both disruption and control tests, males reciprocated frequently between structural bifurcations and other transition points where signal amplitudes changed. Males in the disruption bioassay had to select among vibrational signals combined from the buzzer and the female at each transition point. They often turned towards the buzzer instead of the female. There was a statistically significant reduction in the proportion of males mating if they contacted the buzzer, possibly due to its higher vibration amplitude and duration in comparison with female replies. Potential applications of D. citri mating disruption technology in citrus groves are discussed. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the US.

  8. Transcriptional analysis of porcine intestinal mucosa infected with Salmonella Typhimurium revealed a massive inflammatory response and disruption of bile acid absorption in ileum

    DEFF Research Database (Denmark)

    Uribe, Juber Herrera; Collado-Romero, Melania; Zaldívar-López, Sara

    2016-01-01

    -regulated genes of the FXR pathway (e.g., NR1H4, FABP6, APOA1, SLC10A2), indicating disruption of the bile acid absorption in ileum. This result was confirmed by decreased high-density lipoprotein cholesterol in serum of infected pigs. Ileal inflammatory gene expression changes peaked at 2 dpi and tended...

  9. Disruption of PC1/3 expression in mice causes dwarfism and multiple neuroendocrine peptide processing defects

    DEFF Research Database (Denmark)

    Zhu, Xiaorong; Zhou, An; Dey, Arunangsu

    2002-01-01

    vertebrates and invertebrates. Disruption of the gene-encoding mouse PC1/3 has now been accomplished and results in a syndrome of severe postnatal growth impairment and multiple defects in processing many hormone precursors, including hypothalamic growth hormone-releasing hormone (GHRH), pituitary...

  10. Disruption of STAT5b-Regulated Sexual Dimorphism of the Liver Transcriptome by Diverse Factors Is a Common Event

    Science.gov (United States)

    Signal transducer and activator of transcription 5b (STAT5b) is a growth hormone (GH)-activated transcription factor and a master regulator of sexually dimorphic gene expression in the liver. Disruption ofthe GH hypothalamo-pituitary-liver axis controlling STAT5b activation can ...

  11. Developmental Thyroid Hormone (TH) Disruption: In Search of Sensitive Bioindicators of Altered TH-Dependent Signaling in Brain

    Science.gov (United States)

    Thyroid hormones (TH) are essential for brain development, yet clear indicators of disruption at low levels of TH insufficiency have yet to be identified. Brain TH is difficult to measure, but TH-responsive genes can serve as sensitive indicators of TH action in brain. A large nu...

  12. Developmental Thyroid Hormone (TH) Disruption: In Search of Sensitive Bioindicators of Altered TH-Dependent Signaling in Brain###

    Science.gov (United States)

    Thyroid hormones (TH) are essential for brain development, yet clear indicators of disruption at low levels of TH insufficiency have yet to be identified. Brain TH is difficult to measure, but TH-responsive genes can serve as sensitive indicators of TH action in brain. A large nu...

  13. Targeted disruption of the Mn1 oncogene results in severe defects in development of membranous bones of the cranial skeleton.

    NARCIS (Netherlands)

    M.A. Meester-Smoor (Magda); M. Vermeij (Marcel); M.J. van Helmond (Marjolein); A.C. Molijn (Anco); K.H.M. van Wely (Karel); A.C. Hekman (Arnold); C. Vermey-Keers (Christl); P.H.J. Riegman (Peter); E.C. Zwarthoff (Ellen)

    2005-01-01

    textabstractFusion of the MN1 gene to TEL (ETV6) results in myeloid leukemia. The fusion protein combines the transcription activating domain of MN1 and the DNA binding domain of TEL and is thought to act as a deranged transcription factor. In addition, disruption of the large first exon of the MN1

  14. Literature Review on Disruption Recovery in the Supply Chain

    OpenAIRE

    Ivanov , Dmitry; Dolgui , Alexandre; Sokolov , Boris; Ivanova , Marina

    2017-01-01

    International audience; Recent research underlines the crucial role of disruption events and recovery policies in supply chains. Despite a wealth of literature on supply chain design with disruption considerations, to the best of our knowledge there is no survey on supply chain with disruptions and recovery considerations. We analyse state-of-the-art research streams on supply chain design and planning with both disruptions and recovery considerations with the aim of relating the existing qua...

  15. Cost Sharing in the Prevention of Supply Chain Disruption

    OpenAIRE

    Wen Wang; Kelei Xue; Xiaochen Sun

    2017-01-01

    We examine the influence of cost-sharing mechanism on the disruption prevention investment in a supply chain with unreliable suppliers. When a supply chain faces considerable loss following a disruption, supply chain members are motivated toward investing in manners that reduce their disruption probability. In improving supply chain reliability, the cost-sharing mechanism must be set appropriately to realize the efficiency of the disruption prevention investment. In a supply chain where the f...

  16. A case for change: disruption in academic medicine.

    Science.gov (United States)

    Kahn, Marc J; Maurer, Ralph; Wartman, Steven A; Sachs, Benjamin P

    2014-09-01

    Disruptive technologies allow less expensive and more efficient processes to eventually dominate a market sector. The academic health center's tripartite mission of education, clinical care, and research is threatened by decreasing revenues and increasing expenses and is, as a result, ripe for disruption. The authors describe current disruptive technologies that threaten traditional operations at academic health centers and provide a prescription not only to survive, but also to prosper, in the face of disruptive forces.

  17. Antecedents and implications of disruptive innovation: Evidence from China

    OpenAIRE

    Wan, Feng; Williamson, Peter; Yin, Eden

    2015-01-01

    A growing recognition of the importance of disruptive innovation has led researchers to examine the question of how disruptive innovation comes about and to what extent it reflects "discovery" versus "creation" of opportunities. Earlier research has focused on the organisational preconditions for disruptive innovation to arise. Much less attention has been paid to the role of innovation processes, including their goals and design, in promoting disruptive innovation. In this paper we aim to be...

  18. Tokamak plasma current disruption infrared control system

    International Nuclear Information System (INIS)

    Kugel, H.W.; Ulrickson, M.

    1987-01-01

    This patent describes a device for magnetically confining a plasma driven by a plasma current and contained within a toroidal vacuum chamber, the device having an inner toroidal limiter on an inside wall of the vacuum chamber and an arrangement for the rapid prediction and control in real time of a major plasma disruption. The arrangement is described which includes: scanning means sensitive to infrared radiation emanating from within the vacuum chamber, the infrared radiation indicating the temperature along a vertical profile of the inner toroidal limiter. The scanning means is arranged to observe the infrared radiation and to produce in response thereto an electrical scanning output signal representative of a time scan of temperature along the vertical profile; detection means for analyzing the scanning output signal to detect a first peaked temperature excursion occurring along the profile of the inner toroidal limiter, and to produce a detection output signal in repsonse thereto, the detection output signal indicating a real time prediction of a subsequent major plasma disruption; and plasma current reduction means for reducing the plasma current driving the plasma, in response to the detection output signal and in anticipation of a subsequent major plasma disruption

  19. Disruptive Innovation Can Prevent the Next Pandemic.

    Science.gov (United States)

    Shaikh, Affan T; Ferland, Lisa; Hood-Cree, Robert; Shaffer, Loren; McNabb, Scott J N

    2015-01-01

    Public health surveillance (PHS) is at a tipping point, where the application of novel processes, technologies, and tools promise to vastly improve efficiency and effectiveness. Yet twentieth century, entrenched ideology and lack of training results in slow uptake and resistance to change. The term disruptive innovation - used to describe advances in technology and processes that change existing markets - is useful to describe the transformation of PHS. Past disruptive innovations used in PHS, such as distance learning, the smart phone, and field-based laboratory testing have outpaced older services, practices, and technologies used in the traditional classroom, governmental offices, and personal communication, respectively. Arguably, the greatest of these is the Internet - an infrastructural innovation that continues to enable exponential benefits in seemingly limitless ways. Considering the Global Health Security Agenda and facing emerging and reemerging infectious disease threats, evolving environmental and behavioral risks, and ever changing epidemiologic trends, PHS must transform. Embracing disruptive innovation in the structures and processes of PHS can be unpredictable. However, it is necessary to strengthen and unlock the potential to prevent, detect, and respond.

  20. Disruptive Innovation Can Prevent the Next Pandemic

    Directory of Open Access Journals (Sweden)

    Affan eShaikh

    2015-09-01

    Full Text Available Public health surveillance (PHS is at a tipping point, where the application of novel processes, technologies, and tools promise to vastly improve efficiency and effectiveness. Yet 20th-century, entrenched ideology and lack of training results in slow uptake and resistance to change. The term disruptive innovation – used to describe advances in technology and processes that change existing markets, is useful to describe the transformation of PHS. Past disruptive innovations used in PHS, such as distance learning, the smart phone, and field-based laboratory testing have outpaced older services, practices, and technologies used in the traditional classroom, governmental offices, and personal communication, respectively. Arguably, the greatest of these is the Internet – an infrastructural innovation that continues to enable exponential benefits in seemingly limitless ways. Considering the Global Health Security Agenda and facing emerging and reemerging infectious disease threats, evolving environmental and behavioral risks, and ever changing epidemiologic trends, PHS must transform. Embracing disruptive innovation in the structures and processes of PHS can be unpredictable. However it is necessary to strengthen and unlock the potential to prevent, detect, and respond.

  1. Disruption effects on the beam size measurement

    Energy Technology Data Exchange (ETDEWEB)

    Raimondi, P.; Decker, F.J.; Chen, P.

    1995-06-01

    At the SLC Final Focus with higher currents and smaller beam sizes, the disruption parameter D{sub y} is close to one and so the pinch effect should produce a luminosity enhancement. Since a flat beam-beam function is fit to deflection scan data to measure the beam size, disruption can affect the measurement. Here the authors discuss the quantitative effects of disruption for typical SLC beam parameters. With 3.5 10{sup 10} particles per pulse, bunch length of 0.8 mm and beam sizes of 2.1 {mu}m horizontally and 0.55 {mu}m vertically, the measured vertical size can be as much as 25% bigger than the real one. Furthermore during the collision the spot size actually decrease, producing an enhancement factor H{sub D} of about 1.25. This would yield to a true luminosity which is 1.6 times that which is estimated from the beam-beam deflection fit.

  2. Natural Hazards and Supply Chain Disruptions

    Science.gov (United States)

    Haraguchi, M.

    2016-12-01

    Natural hazards distress the global economy through disruptions in supply chain networks. Moreover, despite increasing investment to infrastructure for disaster risk management, economic damages and losses caused by natural hazards are increasing. Manufacturing companies today have reduced inventories and streamlined logistics in order to maximize economic competitiveness. As a result, today's supply chains are profoundly susceptible to systemic risks, which are the risk of collapse of an entire network caused by a few node of the network. For instance, the prolonged floods in Thailand in 2011 caused supply chain disruptions in their primary industries, i.e. electronic and automotive industries, harming not only the Thai economy but also the global economy. Similar problems occurred after the Great East Japan Earthquake and Tsunami in 2011, the Mississippi River floods and droughts during 2011 - 2013, and the Earthquake in Kumamoto Japan in 2016. This study attempts to discover what kind of effective measures are available for private companies to manage supply chain disruptions caused by floods. It also proposes a method to estimate potential risks using a Bayesian network. The study uses a Bayesian network to create synthetic networks that include variables associated with the magnitude and duration of floods, major components of supply chains such as logistics, multiple layers of suppliers, warehouses, and consumer markets. Considering situations across different times, our study shows desirable data requirements for the analysis and effective measures to improve Value at Risk (VaR) for private enterprises and supply chains.

  3. Runaway electrons beams in ITER disruptions

    International Nuclear Information System (INIS)

    Fleischmann, H.H.

    1993-01-01

    In agreement with the initial projections, the potential generation of runaway beams in disruptions of ITER discharges was performed. This analysis was based on the best-available present projections of plasma parameters existing in large-tokamak disruptions. Using these parameters, the potential contributions from various basic mechanisms for the generation of runway electrons were estimated. The envisioned mechanisms included (i) the well-known Dreicer process (assuming an evaporation of the runways from the thermal distribution), (ii) the seeding of runaway beams resulting from the potential presence of trapped high-temperature electrons from the original discharge still remaining in the disruption plasma at time of reclosure of the magnetic surfaces, and (iii) the generation of runaway beams through avalanche exponentiation of low-level seed runaways resulting via close collisions of existing runaways with cold plasma electrons. Finally, the prospective behavior of the any generated runaway beams -- in particular during their decay -- as well as their potential avoidance and/or damage controlled extraction through the use of magnetic perturbation fields also was considered in some detail

  4. Dynamic shortest path problems : hybrid routing policies considering network disruptions

    NARCIS (Netherlands)

    Sever, D.; Dellaert, N.P.; Woensel, van T.; Kok, de A.G.

    2013-01-01

    Traffic network disruptions lead to significant increases in transportation costs. We consider networks in which a number of links are vulnerable to these disruptions leading to a significantly higher travel time on these links. For these vulnerable links, we consider known link disruption

  5. Feature extraction for improved disruption prediction analysis at JET

    International Nuclear Information System (INIS)

    Ratta, G. A.; Vega, J.; Murari, A.; Johnson, M.

    2008-01-01

    Disruptions are major instabilities and remain one of the main problems in tokomaks. Using Joint European Torus database, a disruption predictor is developed by computational methods including supervised learning techniques. The main objectives of the work are to develop accurate automatic classifiers, to test their performances, and to determine how much in advance of the disruption they can operate with acceptable reliability.

  6. Practice Oriented Algorithmic Disruption Management in Passenger Railways

    NARCIS (Netherlands)

    J.C. Wagenaar (Joris)

    2016-01-01

    markdownabstractHow to deal with a disruption is a question railway companies face on a daily basis. This thesis focusses on the subject how to handle a disruption such that the passenger service is upheld as much as possible. The current mathematical models for disruption management can not yet be

  7. Disruption of Retinol (Vitamin A Signaling by Phthalate Esters: SAR and Mechanism Studies.

    Directory of Open Access Journals (Sweden)

    Yanling Chen

    Full Text Available A spectrum of reproductive system anomalies (cryptorchidism, hypospadias, dysgenesis of Wolffian duct-derived tissues and prostate, and reduced sperm production in male rats exposed in utero to phthalate esters (PEs are thought to be caused by PE inhibition of fetal testosterone production. Recently, dibutyl and dipentyl phthalate (DBuP, DPnP were shown to disrupt the retinol signaling pathway (RSP in mouse pluripotent P19 embryonal carcinoma cells in vitro. The RSP regulates the synthesis and cellular levels of retinoic acid (RA, the active metabolite of retinol (vitamin A. In this new study, a total of 26 di- and mono-esters were screened to identify additional phthalate structures that disrupt the RSP and explore their mechanisms of action. The most potent PEs, those causing > 50% inhibition, contained aryl and cycloalkane groups or C4-C6 alkyl ester chains and were the same PEs reported to cause malformations in utero. They shared similar lipid solubility; logP values were between 4 and 6 and, except for PEs with butyl and phenyl groups, were stable for prolonged periods in culture. Mono- and cognate di-esters varied in ability to disrupt the RSP; e.g., DEHP was inactive but its monoester was active while DBuP was active yet its monoester was inactive. DBuP and dibenzyl phthalate both disrupted the synthesis of RA from retinol but not the ability of RA to activate gene transcription. Both PEs also disrupted the RSP in C3H10T1/2 multipotent mesenchymal stem cells. Based on this in vitro study showing that some PEs disrupt retinol signaling and previous in vivo studies that vitamin A/RA deficiency and PEs both cause strikingly similar anomalies in the male rat reproductive system, we propose that PE-mediated inhibition of testosterone and RA synthesis in utero are both causes of malformations in male rat offspring.

  8. Microarray analysis identifies keratin loci as sensitive biomarkers for thyroid hormone disruption in the salamander Ambystoma mexicanum.

    Science.gov (United States)

    Page, Robert B; Monaghan, James R; Samuels, Amy K; Smith, Jeramiah J; Beachy, Christopher K; Voss, S Randal

    2007-02-01

    Ambystomatid salamanders offer several advantages for endocrine disruption research, including genomic and bioinformatics resources, an accessible laboratory model (Ambystoma mexicanum), and natural lineages that are broadly distributed among North American habitats. We used microarray analysis to measure the relative abundance of transcripts isolated from A. mexicanum epidermis (skin) after exogenous application of thyroid hormone (TH). Only one gene had a >2-fold change in transcript abundance after 2 days of TH treatment. However, hundreds of genes showed significantly different transcript levels at days 12 and 28 in comparison to day 0. A list of 123 TH-responsive genes was identified using statistical, BLAST, and fold level criteria. Cluster analysis identified two groups of genes with similar transcription patterns: up-regulated versus down-regulated. Most notably, several keratins exhibited dramatic (1000 fold) increases or decreases in transcript abundance. Keratin gene expression changes coincided with morphological remodeling of epithelial tissues. This suggests that keratin loci can be developed as sensitive biomarkers to assay temporal disruptions of larval-to-adult gene expression programs. Our study has identified the first collection of loci that are regulated during TH-induced metamorphosis in a salamander, thus setting the stage for future investigations of TH disruption in the Mexican axolotl and other salamanders of the genus Ambystoma.

  9. Triazine herbicides inhibit relaxin signaling and disrupt nitric oxide homeostasis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Si Eun; Lim, Sa Rang; Choi, Hyung-kyoon; Bae, Jeehyeon, E-mail: jeehyeon@cau.ac.kr

    2016-09-15

    Triazines are herbicides that are widely used worldwide, and we previously observed that the maternal exposure of mice to simazine (50 or 500 μg/kg) resulted in smaller ovaries and uteri of their female offspring. Here, we investigated the underlying mechanism that may account for the reproductive dysfunction induced by simazine. We found that following maternal exposure, simazine is transmitted to the offspring, as evidenced by its presence in the offspring ovaries. Analyses of the simazine-exposed offspring revealed that the expression of the relaxin hormone receptor, relaxin-family peptide receptor 1 (RXFP1), prominently decreased in their ovaries and uteri. In addition, downstream target genes of the relaxin pathway including nitric oxide (NO) synthase 2 (Nos2), Nos3, matrix metallopeptidase 9 (Mmp9), and vascular endothelial growth factor (Vegf) were downregulated in their ovaries. Moreover, AKT and extracellular signal-regulated kinases (ERK) levels and their phosphorylated active forms decreased in simazine-exposed ovaries. In vitro exposure of the human ovarian granulosa cells (KGN) and uterine endometrium cells (Hec-1A) to very low concentrations (0.001 to 1 nM) of triazines including atrazine, terbuthylazine, and propazine repressed NO production with a concurrent reduction in RXFP1, NOS2, and NOS3. The inhibitory action of triazines on NO release was dependent on RXFP1, phosphoinositol 3-kinase (PI3K)/AKT, and ERK. Radioligand-binding assay also confirmed that triazines competitively inhibited the binding of relaxin to its receptor. Therefore, the present study suggests that triazine herbicides act as endocrine disrupters by interfering with relaxin hormone signaling. Thus, further evaluation of their impact on human health is imperative. - Highlights: • Triazines downregulate critical molecules involved in the relaxin signaling pathway. • Triazines act as potent antagonists of binding of relaxin to its receptor. • Triazines disrupt nitric oxide

  10. Disruptive coloration in woodland camouflage: evaluation of camouflage effectiveness due to minor disruptive patches

    Science.gov (United States)

    Selj, Gorm K.; Heinrich, Daniela H.

    2016-10-01

    We present results from an observer based photosimulation study of generic camouflage patterns, intended for military uniforms, where three near-identical patterns have been compared. All the patterns were prepared with similar effective color, but were different in how the individual pattern patches were distributed throughout the target. We did this in order to test if high contrast (black) patches along the outline of the target would enhance the survivability when exposed to human observers. In the recent years it has been shown that disruptive coloration in the form of high contrast patches are capable of disturbing an observer by creating false edges of the target and consequently enhance target survivability. This effect has been shown in different forms in the Animal Kingdom, but not to the same extent in camouflaged military targets. The three patterns in this study were i) with no disruptive preference, ii) with a disruptive patch along the outline of the head and iii) with a disruptive patch on the outline of one of the shoulders. We used a high number of human observers to assess the three targets in 16 natural (woodland) backgrounds by showing images of one of the targets at the time on a high definition pc screen. We found that the two patterns that were thought to have a minor disruptive preference to the remaining pattern were more difficult to detect in some (though not all) of the 16 scenes and were also better in overall performance when all the scenes were accounted for.

  11. Neural-net disruption predictor in JT-60U

    International Nuclear Information System (INIS)

    Yoshino, R.

    2003-01-01

    The prediction of major disruptions caused by the density limit, the plasma current ramp-down with high internal inductance l i , the low density locked mode and the β-limit has been investigated in JT-60U. The concept of 'stability level', newly proposed in this paper to predict the occurrence of a major disruption, is calculated from nine input parameters every 2 ms by the neural network and the start of a major disruption is predicted when the stability level decreases to a certain level, the 'alarm level'. The neural network is trained in two steps. It is first trained with 12 disruptive and six non-disruptive shots (total of 8011 data points). Second, the target output data for 12 disruptive shots are modified and the network is trained again with additional data points generated by the operator. The 'neural-net disruption predictor' obtained has been tested for 300 disruptive shots (128 945 data points) and 1008 non-disruptive shots (982 800 data points) selected from nine years of operation (1991-1999) of JT-60U. Major disruptions except for those caused by the -limit have been predicted with a prediction success rate of 97-98% at 10 ms prior to the disruption and higher than 90% at 30 ms prior to the disruption while the false alarm rate is 2.1% for non-disruptive shots. This prediction performance has been confirmed for 120 disruptive shots (56 163 data points), caused by the density limit, as well as 1032 non-disruptive shots (1004 611 data points) in the last four years of operation (1999-2002) of JT-60U. A careful selection of the input parameters supplied to the network and the newly developed two-step training of the network have reduced the false alarm rate resulting in a considerable improvement of the prediction success rate. (author)

  12. Disruption of the FA/BRCA pathway in bladder cancer.

    Science.gov (United States)

    Neveling, K; Kalb, R; Florl, A R; Herterich, S; Friedl, R; Hoehn, H; Hader, C; Hartmann, F H; Nanda, I; Steinlein, C; Schmid, M; Tonnies, H; Hurst, C D; Knowles, M A; Hanenberg, H; Schulz, W A; Schindler, D

    2007-01-01

    Bladder carcinomas frequently show extensive deletions of chromosomes 9p and/or 9q, potentially including the loci of the Fanconi anemia (FA) genes FANCC and FANCG. FA is a rare recessive disease due to defects in anyone of 13 FANC genes manifesting with genetic instability and increased risk of neoplasia. FA cells are hypersensitive towards DNA crosslinking agents such as mitomycin C and cisplatin that are commonly employed in the chemotherapy of bladder cancers. These observations suggest the possibility of disruption of the FA/BRCA DNA repair pathway in bladder tumors. However, mutations in FANCC or FANCG could not be detected in any of 23 bladder carcinoma cell lines and ten surgical tumor specimens by LOH analysis or by FANCD2 immunoblotting assessing proficiency of the pathway. Only a single cell line, BFTC909, proved defective for FANCD2 monoubiquitination and was highly sensitive towards mitomycin C. This increased sensitivity was restored specifically by transfer of the FANCF gene. Sequencing of FANCF in BFTC909 failed to identify mutations, but methylation of cytosine residues in the FANCF promoter region was demonstrated by methylation-specific PCR, HpaII restriction and bisulfite DNA sequencing. Methylation-specific PCR uncovered only a single instance of FANCF promoter hypermethylation in surgical specimens of further 41 bladder carcinomas. These low proportions suggest that in contrast to other types of tumors silencing of FANCF is a rare event in bladder cancer and that an intact FA/BRCA pathway might be advantageous for tumor progression. Copyright (c) 2007 S. Karger AG, Basel.

  13. An organizational assessment of disruptive clinician behavior: findings and implications.

    Science.gov (United States)

    Walrath, Jo M; Dang, Deborah; Nyberg, Dorothy

    2013-01-01

    This study investigated registered nurses' (RNs) and physicians' (MD) experiences with disruptive behavior, triggers, responses, and impacts on clinicians, patients, and the organization. Using the Disruptive Clinician Behavior Survey for Hospital Settings, it was found that RNs experienced a significantly higher frequency of disruptive behaviors and triggers than MDs; MDs (45% of 295) and RNs (37% of 689) reported that their peer's disruptive behavior affected them most negatively. The most frequently occurring trigger was pressure from high census, volume, and patient flow; 189 incidences of harm to patients as a result of disruptive behavior were reported. Findings provide organizational leaders with evidence to customize interventions to strengthen the culture of safety.

  14. Disruption characteristics in PDX with limiter and divertor discharges

    International Nuclear Information System (INIS)

    Couture, P.; McGuire, K.

    1986-09-01

    A comparison has been made between the characteristics of disruptions with limiter and divertor configurations in PDX. A large data base on disruptions has been collected over four years of machine operation, and a total of 15,000 discharges are contained in the data file. It was found that divertor discharges have less disruptions during ramp up and flattop of the plasma current. However, for divertor discharges a large number of fast, low current disruptions take place during the current ramp down. These disruptions are probably caused by the deformation of the plasma shape

  15. Application of the Disruption Predictor Feature Developer to developing a machine-portable disruption predictor

    Science.gov (United States)

    Parsons, Matthew; Tang, William; Feibush, Eliot

    2016-10-01

    Plasma disruptions pose a major threat to the operation of tokamaks which confine a large amount of stored energy. In order to effectively mitigate this damage it is necessary to predict an oncoming disruption with sufficient warning time to take mitigative action. Machine learning approaches to this problem have shown promise but require further developments to address (1) the need for machine-portable predictors and (2) the availability of multi-dimensional signal inputs. Here we demonstrate progress in these two areas by applying the Disruption Predictor Feature Developer to data from JET and NSTX, and discuss topics of focus for ongoing work in support of ITER. The author is also supported under the Fulbright U.S. Student Program as a graduate student in the department of Nuclear, Plasma and Radiological Engineering at the University of Illinois at Urbana-Champaign.

  16. Disruption Physics and Mitigation on DIII-D

    International Nuclear Information System (INIS)

    Whyte, D.G.; Humphreys, D.A.; Kellman, A.G.

    2005-01-01

    The contributions of the DIII-D tokamak toward the understanding and control of disruptions are reviewed. Disruptions are found to be deterministic, and the underlying causes of disruption can therefore be predicted and avoided. With sufficiently rapid detection, possible damage from disruptions can be mitigated using an understanding of disruption phenomenology and plasma physics. Regimes of high β are readily available in DIII-D and provide access to relatively high energy density disruptions, despite DIII-D's moderate magnetic field and size. DIII-D, with all-graphite wall armor and wall conditioning between discharges, has proven highly resilient to the deleterious effects that disruptions can have on plasma operations. Simultaneously, exploitation and adaptation of DIII-D's extensive core and edge plasma diagnostic set have allowed for unique plasma measurements during disruptions. These measurements have tied into the development of several physical models used to understand aspects of disruptions, such as magnetohydrodynamic growth at the disruption onset, radiation energy balance through the thermal quench, and halo currents during the current quench. Based on this fundamental understanding, DIII-D has developed techniques to mitigate the harmful effects of disruptions by radiative dissipation of the plasma energy and extrapolated these techniques for possible use on larger devices like ITER

  17. Fetal brain disruption sequence versus fetal brain arrest: A distinct autosomal recessive developmental brain malformation phenotype.

    Science.gov (United States)

    Abdel-Salam, Ghada M H; Abdel-Hamid, Mohamed S; El-Khayat, Hamed A; Eid, Ola M; Saba, Soliman; Farag, Mona K; Saleem, Sahar N; Gaber, Khaled R

    2015-05-01

    The term fetal brain disruption sequence (FBDS) was coined to describe a number of sporadic conditions caused by numerous external disruptive events presenting with variable imaging findings. However, rare familial occurrences have been reported. We describe five patients (two sib pairs and one sporadic) with congenital severe microcephaly, seizures, and profound intellectual disability. Brain magnetic resonance imaging (MRI) revealed unique and uniform picture of underdeveloped cerebral hemispheres with increased extraxial CSF, abnormal gyral pattern (polymicrogyria-like lesions in two sibs and lissencephaly in the others), loss of white matter, dysplastic ventricles, hypogenesis of corpus callosum, and hypoplasia of the brainstem, but hypoplastic cerebellum in one. Fetal magnetic resonance imaging (FMRI) of two patients showed the same developmental brain malformations in utero. These imaging findings are in accordance with arrested brain development rather than disruption. Molecular analysis excluded mutations in potentially related genes such as NDE1, MKL2, OCLN, and JAM3. These unique clinical and imaging findings were described before among familial reports with FBDS. However, our patients represent a recognizable phenotype of developmental brain malformations, that is, apparently distinguishable from either familial microhydranencephaly or microlissencephaly that were collectively termed FBDS. Thus, the use of the umbrella term FBDS is no longer helpful. Accordingly, we propose the term fetal brain arrest to distinguish them from other familial patients diagnosed as FBDS. The presence of five affected patients from three unrelated consanguineous families suggests an autosomal-recessive mode of inheritance. The spectrum of fetal brain disruption sequence is reviewed. © 2015 Wiley Periodicals, Inc.

  18. An overview on plasma disruption mitigation and avoidance in tokamak

    International Nuclear Information System (INIS)

    He Kaihui; Pan Chuanhong; Feng Kaiming

    2002-01-01

    Plasma disruption, which seems to be unavoidable in Tokamak operation, occurs very fast and uncontrolled. In order to keep Tokamak plasma from disruption and mitigate the disruption frequency, the research on Tokamak plasma major disruption constitutes one of the main topics in plasma physics. The phenomena and processes of the precursor, thermal quench, current quench, VDE, halo current and runaway electrons generation during plasma disruption are analyzed in detail and systematically based on the data obtained from current Tokamaks such as TFTR, JET, JT-60U and ASDEX-U, etc. The methods to mitigate and avoid disruption in Tokamak are also highlighted schematically. Therefore, it is helpful and instructive for plasma disruption research in next generation large Tokamak such as ITER-FEAT

  19. Bisphenol A accumulation in eggs disrupts the endocrine regulation of growth in rainbow trout larvae

    Energy Technology Data Exchange (ETDEWEB)

    Birceanu, Oana; Servos, Mark R.; Vijayan, Mathilakath M., E-mail: matt.vijayan@ucalgary.ca

    2015-04-15

    Highlights: • BPA in eggs reduces growth and increases food conversion ratio in trout larvae. • BPA in eggs disrupts larval transcript abundance of genes involved in GH/IGF axis. • BPA in eggs disrupts thyroid hormone receptor mRNA levels. • BPA in eggs consistently suppressed IGF-1rb mRNA levels during early development. - Abstract: Bisphenol A (BPA), a monomer used in the production of plastics and epoxy resins, is ubiquitously present in the aquatic environment. BPA is considered a weak estrogen in fish, but the effects of this chemical on early developmental events are far from clear. We tested the hypothesis that BPA accumulation in eggs, mimicking maternal transfer, disrupts growth hormone/insulin-like growth factor (GH/IGF) axis function, leading to defects in larval growth in rainbow trout. Trout oocytes were exposed to 0 (control), 0.3, 3, and 30 μg ml{sup −1} BPA for 3 h, which led to an accumulation of around 0, 1, 4 and 40 ng BPA per egg, respectively. All treatment groups were fertilized with clean milt and reared in clean water for the rest of the experiment. The embryo BPA content declined over time in all groups and was completely eliminated by 42 days post-fertilization (dpf). Hatchlings from BPA accumulated eggs had higher water content and reduced total energy levels prior to first feed. There was an overall reduction in the specific growth rate and food conversion ratio in larvae reared from BPA-laden eggs. BPA accumulation disrupted the mRNA abundance of genes involved in GH/IGF axis function, including GH isoforms and their receptors, IGF-1 and -2 and IGF receptors, in a life stage-dependent manner. Also, there was a temporal disruption in the mRNA levels of thyroid hormone receptors in the larvae raised from BPA-laden eggs. Altogether, BPA accumulation in eggs, mimicking maternal transfer, affects larval growth and the mode of action involves disruption of genes involved in the GH/IGF and thyroid axes function in trout.

  20. Bisphenol A accumulation in eggs disrupts the endocrine regulation of growth in rainbow trout larvae

    International Nuclear Information System (INIS)

    Birceanu, Oana; Servos, Mark R.; Vijayan, Mathilakath M.

    2015-01-01

    Highlights: • BPA in eggs reduces growth and increases food conversion ratio in trout larvae. • BPA in eggs disrupts larval transcript abundance of genes involved in GH/IGF axis. • BPA in eggs disrupts thyroid hormone receptor mRNA levels. • BPA in eggs consistently suppressed IGF-1rb mRNA levels during early development. - Abstract: Bisphenol A (BPA), a monomer used in the production of plastics and epoxy resins, is ubiquitously present in the aquatic environment. BPA is considered a weak estrogen in fish, but the effects of this chemical on early developmental events are far from clear. We tested the hypothesis that BPA accumulation in eggs, mimicking maternal transfer, disrupts growth hormone/insulin-like growth factor (GH/IGF) axis function, leading to defects in larval growth in rainbow trout. Trout oocytes were exposed to 0 (control), 0.3, 3, and 30 μg ml −1 BPA for 3 h, which led to an accumulation of around 0, 1, 4 and 40 ng BPA per egg, respectively. All treatment groups were fertilized with clean milt and reared in clean water for the rest of the experiment. The embryo BPA content declined over time in all groups and was completely eliminated by 42 days post-fertilization (dpf). Hatchlings from BPA accumulated eggs had higher water content and reduced total energy levels prior to first feed. There was an overall reduction in the specific growth rate and food conversion ratio in larvae reared from BPA-laden eggs. BPA accumulation disrupted the mRNA abundance of genes involved in GH/IGF axis function, including GH isoforms and their receptors, IGF-1 and -2 and IGF receptors, in a life stage-dependent manner. Also, there was a temporal disruption in the mRNA levels of thyroid hormone receptors in the larvae raised from BPA-laden eggs. Altogether, BPA accumulation in eggs, mimicking maternal transfer, affects larval growth and the mode of action involves disruption of genes involved in the GH/IGF and thyroid axes function in trout

  1. Norrie disease gene is distinct from the monoamine oxidase genes.

    Science.gov (United States)

    Sims, K B; Ozelius, L; Corey, T; Rinehart, W B; Liberfarb, R; Haines, J; Chen, W J; Norio, R; Sankila, E; de la Chapelle, A

    1989-09-01

    The genes for MAO-A and MAO-B appear to be very close to the Norrie disease gene, on the basis of loss and/or disruption of the MAO genes and activities in atypical Norrie disease patients deleted for the DXS7 locus; linkage among the MAO genes, the Norrie disease gene, and the DXS7 locus; and mapping of all these loci to the chromosomal region Xp11. The present study provides evidence that the MAO genes are not disrupted in "classic" Norrie disease patients. Genomic DNA from these "nondeletion" Norrie disease patients did not show rearrangements at the MAOA or DXS7 loci. Normal levels of MAO-A activities, as well as normal amounts and size of the MAO-A mRNA, were observed in cultured skin fibroblasts from these patients, and MAO-B activity in their platelets was normal. Catecholamine metabolites evaluated in plasma and urine were in the control range. Thus, although some atypical Norrie disease patients lack both MAO-A and MAO-B activities, MAO does not appear to be an etiologic factor in classic Norrie disease.

  2. Pheromone disruption of Argentine ant trail integrity

    Science.gov (United States)

    Suckling, D.M.; Peck, R.W.; Manning, L.M.; Stringer, L.D.; Cappadonna, J.; El-Sayed, A. M.

    2008-01-01

    Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. ?? 2008 Springer Science+Business Media, LLC.

  3. Estrogens can disrupt amphibian mating behavior.

    Directory of Open Access Journals (Sweden)

    Frauke Hoffmann

    Full Text Available The main component of classical contraceptives, 17α-ethinylestradiol (EE2, has high estrogenic activity even at environmentally relevant concentrations. Although estrogenic endocrine disrupting compounds are assumed to contribute to the worldwide decline of amphibian populations by adverse effects on sexual differentiation, evidence for EE2 affecting amphibian mating behaviour is lacking. In this study, we demonstrate that EE2 exposure at five different concentrations (0.296 ng/L, 2.96 ng/L, 29.64 ng/L, 2.96 µg/L and 296.4 µg/L can disrupt the mating behavior of adult male Xenopus laevis. EE2 exposure at all concentrations lowered male sexual arousal, indicated by decreased proportions of advertisement calls and increased proportions of the call type rasping, which characterizes a sexually unaroused state of a male. Additionally, EE2 at all tested concentrations affected temporal and spectral parameters of the advertisement calls, respectively. The classical and highly sensitive biomarker vitellogenin, on the other hand, was only induced at concentrations equal or higher than 2.96 µg/L. If kept under control conditions after a 96 h EE2 exposure (2.96 µg/L, alterations of male advertisement calls vanish gradually within 6 weeks and result in a lower sexual attractiveness of EE2 exposed males toward females as demonstrated by female choice experiments. These findings indicate that exposure to environmentally relevant EE2 concentrations can directly disrupt male mate calling behavior of X. laevis and can indirectly affect the mating behavior of females. The results suggest the possibility that EE2 exposure could reduce the reproductive success of EE2 exposed animals and these effects might contribute to the global problem of amphibian decline.

  4. Physics and observations of tidal disruption events

    Science.gov (United States)

    Mangalam, Arun; Mageshwaran, Tamilan

    2018-04-01

    We describe a model of tidal disruption events (TDEs) with input physical parameters that include the black hole (BH) mass M•, the specific orbital energy E, the angular momentum J, the star mass M⊙ and radius R⊙. We calculate the rise time of the TDEs, the peak bolometric luminosity in terms of these physical parameters and a typical light curve of TDEs for various All Sky Survey (ASS) and Deep Sky Survey (DSS) missions. We then derive the expected detection rates and discuss the follow up of TDEs through observations in various spectral bands from X-rays to radio wavelengths.

  5. Disruptive Innovation by Emerging Multinational Latecomers

    DEFF Research Database (Denmark)

    Li, Peter Ping

    Despite the growing interest in the emerging-economy multinational enterprise (EMNE), there is little knowledge about the underlying mechanism for EMNEs as latecomers to catch up with and even leapfrog the traditional MNEs as early-movers. The cross-fertilization between the research streams...... of latecomer innovation as a special DI by EMNE at BOP to provide insights into the mechanisms underlying the trajectories of catching up and leapfrogging. Built upon latecomer innovation, EMNEs at BOP can emerge as the most disruptive challengers to the MNE incumbents at TOP. The implications of reframed...... constructs, integrative typology, and emerging theory for research and practice are also discussed....

  6. Moore's Law, disruptive technologies, and the clinician.

    Science.gov (United States)

    Vosburgh, Kirby G; Newbower, Ronald S

    2002-01-01

    The advancement of technical power described by Moore's Law offers great potential for enabling more cost-effective medical devices and systems. However, progress has been slow. Many factors for this failure have been cited, including the anti-rational economic structure of healthcare and the complexity and long time scale of medical development. Christensen et al. suggest that "disruptive technologies" may circumvent some of these difficulties. "Disruptive Technologies" are defined as those that are established in one market, but then penetrate and overwhelm another market. These incursions are accelerated by economic factors, and capitalize on functionality, reliability, and advancements supported by the original market. Christensen has cited many examples from industrial and service businesses, but few examples can be found yet in healthcare. We argue that positive technology impacts in medicine occur most readily when innovators augment the skills of and collaborate with caregivers, rather than seeking to displace them. In the short term, a new approach may improve efficiency or quality. In the longer term, such approaches may obviate human tasks at lower-skill levels, and even permit task automation. One successful example has been the introduction of flexible monitoring for physiologic information. Systems for computer-aided diagnosis, which have failed to impact complex decision making, have succeeded in simpler specialty areas such as the interpretation of EKG's and mammograms, and may do the same with analysis of some pathology images. The next frontier may the operating room, and the adoption of such systemic technologies by caregivers in emergency medicine and general care may then have an even wider "disruptive" effect. Responding to time and cost pressures, and the desire to move care to the patient, other workers, such as radiologists, will drive the trend away from isolated, complex, large-scale devices, and toward integrated, modular, and simpler

  7. Traumatic ureteropelvic disruption in the child

    International Nuclear Information System (INIS)

    Reda, E.T.; Lebowitz, R.L.

    1986-01-01

    Traumatic disruption of the ureter from the renal pelvis is a rare injury because the ureteropelvic junction is situated deep in the retroperitoneum and is thus protected by the spine and paraspinal muscles. The mechanism for this injury is thought to be the stretching of the proximal ureter by sudden extreme hyperextension of the trunk. As a non-fatal injury, this occurs only in the child because of the greater elasticity and mobility of the young skeleton. At The Children's Hospital we have seen 3 cases of avulsion of the ureter from the pelvis following blunt trauma. (orig.)

  8. Electrical disruption in toroidal plasma of hydrogen

    International Nuclear Information System (INIS)

    Roberto, M.; Silva, C.A.B.; Goes, L.C.S.; Sudano, J.P.

    1991-01-01

    The initial phase of ionization of a toroidal plasma produced in hydrogen was investigated using zero-dimensional model. The model describes the temporal evolution of plasma by spatial medium of particle density and temperature, on whole plasma volume. The energy and particle (electrons and ions) balance equations are considered. The electron loss is due to ambipolar diffusion in the presence of magnetic field. The electron energy loss involves ionization, Coulomb interaction and diffusion. The ohmic heating converter gives the initial voltage necessary to disruption. (M.C.K.)

  9. Disruptive Innovation in Air Measurement Technology: Reality ...

    Science.gov (United States)

    This presentation is a big picture overview on the changing state of air measurement technology in the world, with a focus on the introduction of low-cost sensors into the market place. The presentation discusses how these new technologies may be a case study in disruptive innovation for the air pollution measurement field. The intended audience is primarily those with experience in air pollution measurement methods, but much of the talk is accessible to the general public. This is a keynote presentation on emerging air monitoring technology, to be provided at the AWMA measurements conference in March, 2016.

  10. Multimedia data mining and analytics disruptive innovation

    CERN Document Server

    Baughman, Aaron; Pan, Jia-Yu; Petrushin, Valery A

    2015-01-01

    This authoritative text/reference provides fresh insights into the cutting edge of multimedia data mining, reflecting how the research focus has shifted towards networked social communities, mobile devices and sensors. Presenting a detailed exploration into the progression of the field, the book describes how the history of multimedia data processing can be viewed as a sequence of disruptive innovations. Across the chapters, the discussion covers the practical frameworks, libraries, and open source software that enable the development of ground-breaking research into practical applications.

  11. Valproic acid disrupts the oscillatory expression of core circadian rhythm transcription factors.

    Science.gov (United States)

    Griggs, Chanel A; Malm, Scott W; Jaime-Frias, Rosa; Smith, Catharine L

    2018-01-15

    Valproic acid (VPA) is a well-established therapeutic used in treatment of seizure and mood disorders as well as migraines and a known hepatotoxicant. About 50% of VPA users experience metabolic disruptions, including weight gain, hyperlipidemia, and hyperinsulinemia, among others. Several of these metabolic abnormalities are similar to the effects of circadian rhythm disruption. In the current study, we examine the effect of VPA exposure on the expression of core circadian transcription factors that drive the circadian clock via a transcription-translation feedback loop. In cells with an unsynchronized clock, VPA simultaneously upregulated the expression of genes encoding core circadian transcription factors that regulate the positive and negative limbs of the feedback loop. Using low dose glucocorticoid, we synchronized cultured fibroblast cells to a circadian oscillatory pattern. Whether VPA was added at the time of synchronization or 12h later at CT12, we found that VPA disrupted the oscillatory expression of multiple genes encoding essential transcription factors that regulate circadian rhythm. Therefore, we conclude that VPA has a potent effect on the circadian rhythm transcription-translation feedback loop that may be linked to negative VPA side effects in humans. Furthermore, our study suggests potential chronopharmacology implications of VPA usage. Copyright © 2017. Published by Elsevier Inc.

  12. Gene Therapy

    Science.gov (United States)

    Gene therapy Overview Gene therapy involves altering the genes inside your body's cells in an effort to treat or stop disease. Genes contain your ... that don't work properly can cause disease. Gene therapy replaces a faulty gene or adds a new ...

  13. Smog induces oxidative stress and microbiota disruption.

    Science.gov (United States)

    Wong, Tit-Yee

    2017-04-01

    Smog is created through the interactions between pollutants in the air, fog, and sunlight. Air pollutants, such as carbon monoxide, heavy metals, nitrogen oxides, ozone, sulfur dioxide, volatile organic vapors, and particulate matters, can induce oxidative stress in human directly or indirectly through the formation of reactive oxygen species. The outermost boundary of human skin and mucous layers are covered by a complex network of human-associated microbes. The relation between these microbial communities and their human host are mostly mutualistic. These microbes not only provide nutrients, vitamins, and protection against other pathogens, they also influence human's physical, immunological, nutritional, and mental developments. Elements in smog can induce oxidative stress to these microbes, leading to community collapse. Disruption of these mutualistic microbiota may introduce unexpected health risks, especially among the newborns and young children. Besides reducing the burning of fossil fuels as the ultimate solution of smog formation, advanced methods by using various physical, chemical, and biological means to reduce sulfur and nitrogen contains in fossil fuels could lower smog formation. Additionally, information on microbiota disruption, based on functional genomics, culturomics, and general ecological principles, should be included in the risk assessment of prolonged smog exposure to the health of human populations. Copyright © 2017. Published by Elsevier B.V.

  14. Features, Events, and Processes: Disruptive Events

    Energy Technology Data Exchange (ETDEWEB)

    P. Sanchez

    2004-11-08

    The purpose of this analysis report is to evaluate and document the inclusion or exclusion of the disruptive events features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment for license application (TSPA-LA). A screening decision, either ''Included'' or ''Excluded,'' is given for each FEP, along with the technical basis for screening decisions. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.114 (d), (e), and (f) [DIRS 156605]. The FEPs addressed in this report deal with both seismic and igneous disruptive events, such as fault displacements through the repository and an igneous intrusion into the repository. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded). Previous versions of this report were developed to support the total system performance assessments (TSPA) for various prior repository designs. This revision addresses the repository design for the license application (LA).

  15. Features, Events, and Processes: Disruptive Events

    International Nuclear Information System (INIS)

    P. Sanchez

    2004-01-01

    The purpose of this analysis report is to evaluate and document the inclusion or exclusion of the disruptive events features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment for license application (TSPA-LA). A screening decision, either ''Included'' or ''Excluded,'' is given for each FEP, along with the technical basis for screening decisions. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.114 (d), (e), and (f) [DIRS 156605]. The FEPs addressed in this report deal with both seismic and igneous disruptive events, such as fault displacements through the repository and an igneous intrusion into the repository. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded). Previous versions of this report were developed to support the total system performance assessments (TSPA) for various prior repository designs. This revision addresses the repository design for the license application (LA)

  16. Modeling Steroidogenesis Disruption Using High-Throughput ...

    Science.gov (United States)

    Environmental chemicals can elicit endocrine disruption by altering steroid hormone biosynthesis and metabolism (steroidogenesis) causing adverse reproductive and developmental effects. Historically, a lack of assays resulted in few chemicals having been evaluated for effects on steroidogenesis. The steroidogenic pathway is a series of hydroxylation and dehydrogenation steps carried out by CYP450 and hydroxysteroid dehydrogenase enzymes, yet the only enzyme in the pathway for which a high-throughput screening (HTS) assay has been developed is aromatase (CYP19A1), responsible for the aromatization of androgens to estrogens. Recently, the ToxCast HTS program adapted the OECD validated H295R steroidogenesis assay using human adrenocortical carcinoma cells into a high-throughput model to quantitatively assess the concentration-dependent (0.003-100 µM) effects of chemicals on 10 steroid hormones including progestagens, androgens, estrogens and glucocorticoids. These results, in combination with two CYP19A1 inhibition assays, comprise a large dataset amenable to clustering approaches supporting the identification and characterization of putative mechanisms of action (pMOA) for steroidogenesis disruption. In total, 514 chemicals were tested in all CYP19A1 and steroidogenesis assays. 216 chemicals were identified as CYP19A1 inhibitors in at least one CYP19A1 assay. 208 of these chemicals also altered hormone levels in the H295R assay, suggesting 96% sensitivity in the

  17. Disrupted sensory gating in pathological gambling.

    Science.gov (United States)

    Stojanov, Wendy; Karayanidis, Frini; Johnston, Patrick; Bailey, Andrew; Carr, Vaughan; Schall, Ulrich

    2003-08-15

    Some neurochemical evidence as well as recent studies on molecular genetics suggest that pathologic gambling may be related to dysregulated dopamine neurotransmission. The current study examined sensory (motor) gating in pathologic gamblers as a putative measure of endogenous brain dopamine activity with prepulse inhibition of the acoustic startle eye-blink response and the auditory P300 event-related potential. Seventeen pathologic gamblers and 21 age- and gender-matched healthy control subjects were assessed. Both prepulse inhibition measures were recorded under passive listening and two-tone prepulse discrimination conditions. Compared to the control group, pathologic gamblers exhibited disrupted sensory (motor) gating on all measures of prepulse inhibition. Sensory motor gating deficits of eye-blink responses were most profound at 120-millisecond prepulse lead intervals in the passive listening task and at 240-millisecond prepulse lead intervals in the two-tone prepulse discrimination task. Sensory gating of P300 was also impaired in pathologic gamblers, particularly at 500-millisecond lead intervals, when performing the discrimination task on the prepulse. In the context of preclinical studies on the disruptive effects of dopamine agonists on prepulse inhibition, our findings suggest increased endogenous brain dopamine activity in pathologic gambling in line with previous neurobiological findings.

  18. Turbulence associated with the sawtooth internal disruption

    International Nuclear Information System (INIS)

    Andreoletti, J.; Laviron, C.; Olivain, J.; Pecquet, A.L.

    1989-05-01

    Specific turbulence associated with the sawtooth internal disruption has been observed on TFR tokamak plasmas by analyzing density fluctuations with CO 2 laser light scattering. The time localization is clearly connected with the successive phases of the relaxation process. Some specific turbulence appears in relation to the kink motion, but the main burst corresponds to the collapse phase. We concentrate our study on this strong burst and show first its frequency and wave number spectral properties and the corresponding pseudo dispersion relation. The specific turbulence is spatially localized. It is within the interior of the q = 1 surface and extends approximately 120 0 azimuthally. Taking into account the twisting of the central plasma during the turbulent kink phase, this location agrees with the azimuthal position of the ''sooner and faster'' outgoing heat flux. The power level of this turbulence is two orders of magnitude larger than the local quasi-stationary turbulence. These observations are in fair agreement with the predictions of the sawtooth disruption model previously proposed by Andreoletti. The observed specific turbulence shows several similarities with the so called ''magnetodrift turbulence'' described in the model

  19. Disruptive mood dysregulation disorder: current insights

    Directory of Open Access Journals (Sweden)

    Baweja R

    2016-08-01

    Full Text Available Raman Baweja, Susan D Mayes, Usman Hameed, James G Waxmonsky Department of Psychiatry, Penn State University College of Medicine, Hershey, PA, USA Abstract: Disruptive mood dysregulation disorder (DMDD was introduced as a new diagnostic entity under the category of depressive disorders in Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5. It was included in DSM-5 primarily to address concerns about the misdiagnosis and consequent overtreatment of bipolar disorder in children and adolescents. DMDD does provide a home for a large percentage of referred children with severe persistent irritability that did not fit well into any DSM, Fourth Edition (DSM-IV diagnostic category. However, it has been a controversial addition to the DSM-5 due to lack of published validity studies, leading to questions about its validity as a distinct disorder. In this article, the authors discuss the diagnostic criteria, assessment, epidemiology, criticism of the diagnosis, and pathophysiology, as well as treatment and future directions for DMDD. They also review the literature on severe mood dysregulation, as described by the National Institute of Mental Health, as the scientific support for DMDD is based primarily on studies of severe mood dysregulation. Keywords: disruptive mood dysregulation disorder, persistent irritability, temper outbursts 

  20. Overvoltage protection for magnetic system during disruption in tokamak

    International Nuclear Information System (INIS)

    Zhang, Ming; Li, Xiaolong; He, Yang; Zhang, Jun; Chen, Zhongyong; Yu, Kexun

    2015-01-01

    Highlights: • We investigate the way to limit the plasma disruption overvoltage by using the MOVs. • An overvoltage model of plasma disruption is introduced. • The overvoltage protection scheme has been verified by disruption experiments. • The overvoltage during plasma disruption can be limited to 330 V. - Abstract: During a plasma disruption the magnetic flux in the tokamak changes rapidly, which in most cases will cause high-voltage surges among the magnetic systems and may bring severe damage to the components if there is no overvoltage protection. This paper investigates the way to limit the plasma disruption overvoltage and absorb the energy with the use of metal oxide varistors (MOVs). An overvoltage model of plasma disruption is introduced which can be used for the simulation of plasma disruption and the analysis of the overvoltage. The effectiveness of the overvoltage protection system is validated with disruption experiments. It shows that by optimizing the varistors voltage, the overvoltage during plasma disruption can be limited to an ideal low value. Now the overvoltage protection system has been deployed in J-TEXT tokamak and serves well for daily experiments.